diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/discrete/tests/test_transforms.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/discrete/tests/test_transforms.py new file mode 100644 index 0000000000000000000000000000000000000000..385514be4cdec2f19cf3a750bdbe0f4f6e21cc6e --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/discrete/tests/test_transforms.py @@ -0,0 +1,154 @@ +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.core import S, Symbol, symbols, I, Rational +from sympy.discrete import (fft, ifft, ntt, intt, fwht, ifwht, + mobius_transform, inverse_mobius_transform) +from sympy.testing.pytest import raises + + +def test_fft_ifft(): + assert all(tf(ls) == ls for tf in (fft, ifft) + for ls in ([], [Rational(5, 3)])) + + ls = list(range(6)) + fls = [15, -7*sqrt(2)/2 - 4 - sqrt(2)*I/2 + 2*I, 2 + 3*I, + -4 + 7*sqrt(2)/2 - 2*I - sqrt(2)*I/2, -3, + -4 + 7*sqrt(2)/2 + sqrt(2)*I/2 + 2*I, + 2 - 3*I, -7*sqrt(2)/2 - 4 - 2*I + sqrt(2)*I/2] + + assert fft(ls) == fls + assert ifft(fls) == ls + [S.Zero]*2 + + ls = [1 + 2*I, 3 + 4*I, 5 + 6*I] + ifls = [Rational(9, 4) + 3*I, I*Rational(-7, 4), Rational(3, 4) + I, -2 - I/4] + + assert ifft(ls) == ifls + assert fft(ifls) == ls + [S.Zero] + + x = Symbol('x', real=True) + raises(TypeError, lambda: fft(x)) + raises(ValueError, lambda: ifft([x, 2*x, 3*x**2, 4*x**3])) + + +def test_ntt_intt(): + # prime moduli of the form (m*2**k + 1), sequence length + # should be a divisor of 2**k + p = 7*17*2**23 + 1 + q = 2*500000003 + 1 # only for sequences of length 1 or 2 + r = 2*3*5*7 # composite modulus + + assert all(tf(ls, p) == ls for tf in (ntt, intt) + for ls in ([], [5])) + + ls = list(range(6)) + nls = [15, 801133602, 738493201, 334102277, 998244350, 849020224, + 259751156, 12232587] + + assert ntt(ls, p) == nls + assert intt(nls, p) == ls + [0]*2 + + ls = [1 + 2*I, 3 + 4*I, 5 + 6*I] + x = Symbol('x', integer=True) + + raises(TypeError, lambda: ntt(x, p)) + raises(ValueError, lambda: intt([x, 2*x, 3*x**2, 4*x**3], p)) + raises(ValueError, lambda: intt(ls, p)) + raises(ValueError, lambda: ntt([1.2, 2.1, 3.5], p)) + raises(ValueError, lambda: ntt([3, 5, 6], q)) + raises(ValueError, lambda: ntt([4, 5, 7], r)) + raises(ValueError, lambda: ntt([1.0, 2.0, 3.0], p)) + + +def test_fwht_ifwht(): + assert all(tf(ls) == ls for tf in (fwht, ifwht) \ + for ls in ([], [Rational(7, 4)])) + + ls = [213, 321, 43235, 5325, 312, 53] + fls = [49459, 38061, -47661, -37759, 48729, 37543, -48391, -38277] + + assert fwht(ls) == fls + assert ifwht(fls) == ls + [S.Zero]*2 + + ls = [S.Half + 2*I, Rational(3, 7) + 4*I, Rational(5, 6) + 6*I, Rational(7, 3), Rational(9, 4)] + ifls = [Rational(533, 672) + I*3/2, Rational(23, 224) + I/2, Rational(1, 672), Rational(107, 224) - I, + Rational(155, 672) + I*3/2, Rational(-103, 224) + I/2, Rational(-377, 672), Rational(-19, 224) - I] + + assert ifwht(ls) == ifls + assert fwht(ifls) == ls + [S.Zero]*3 + + x, y = symbols('x y') + + raises(TypeError, lambda: fwht(x)) + + ls = [x, 2*x, 3*x**2, 4*x**3] + ifls = [x**3 + 3*x**2/4 + x*Rational(3, 4), + -x**3 + 3*x**2/4 - x/4, + -x**3 - 3*x**2/4 + x*Rational(3, 4), + x**3 - 3*x**2/4 - x/4] + + assert ifwht(ls) == ifls + assert fwht(ifls) == ls + + ls = [x, y, x**2, y**2, x*y] + fls = [x**2 + x*y + x + y**2 + y, + x**2 + x*y + x - y**2 - y, + -x**2 + x*y + x - y**2 + y, + -x**2 + x*y + x + y**2 - y, + x**2 - x*y + x + y**2 + y, + x**2 - x*y + x - y**2 - y, + -x**2 - x*y + x - y**2 + y, + -x**2 - x*y + x + y**2 - y] + + assert fwht(ls) == fls + assert ifwht(fls) == ls + [S.Zero]*3 + + ls = list(range(6)) + + assert fwht(ls) == [x*8 for x in ifwht(ls)] + + +def test_mobius_transform(): + assert all(tf(ls, subset=subset) == ls + for ls in ([], [Rational(7, 4)]) for subset in (True, False) + for tf in (mobius_transform, inverse_mobius_transform)) + + w, x, y, z = symbols('w x y z') + + assert mobius_transform([x, y]) == [x, x + y] + assert inverse_mobius_transform([x, x + y]) == [x, y] + assert mobius_transform([x, y], subset=False) == [x + y, y] + assert inverse_mobius_transform([x + y, y], subset=False) == [x, y] + + assert mobius_transform([w, x, y, z]) == [w, w + x, w + y, w + x + y + z] + assert inverse_mobius_transform([w, w + x, w + y, w + x + y + z]) == \ + [w, x, y, z] + assert mobius_transform([w, x, y, z], subset=False) == \ + [w + x + y + z, x + z, y + z, z] + assert inverse_mobius_transform([w + x + y + z, x + z, y + z, z], subset=False) == \ + [w, x, y, z] + + ls = [Rational(2, 3), Rational(6, 7), Rational(5, 8), 9, Rational(5, 3) + 7*I] + mls = [Rational(2, 3), Rational(32, 21), Rational(31, 24), Rational(1873, 168), + Rational(7, 3) + 7*I, Rational(67, 21) + 7*I, Rational(71, 24) + 7*I, + Rational(2153, 168) + 7*I] + + assert mobius_transform(ls) == mls + assert inverse_mobius_transform(mls) == ls + [S.Zero]*3 + + mls = [Rational(2153, 168) + 7*I, Rational(69, 7), Rational(77, 8), 9, Rational(5, 3) + 7*I, 0, 0, 0] + + assert mobius_transform(ls, subset=False) == mls + assert inverse_mobius_transform(mls, subset=False) == ls + [S.Zero]*3 + + ls = ls[:-1] + mls = [Rational(2, 3), Rational(32, 21), Rational(31, 24), Rational(1873, 168)] + + assert mobius_transform(ls) == mls + assert inverse_mobius_transform(mls) == ls + + mls = [Rational(1873, 168), Rational(69, 7), Rational(77, 8), 9] + + assert mobius_transform(ls, subset=False) == mls + assert inverse_mobius_transform(mls, subset=False) == ls + + raises(TypeError, lambda: mobius_transform(x, subset=True)) + raises(TypeError, lambda: inverse_mobius_transform(y, subset=False)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..549b4b96cdce0ee4d31960e89cb9dc26af0e105d --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/__init__.py @@ -0,0 +1,20 @@ +""" +Unified place for determining if external dependencies are installed or not. + +You should import all external modules using the import_module() function. + +For example + +>>> from sympy.external import import_module +>>> numpy = import_module('numpy') + +If the resulting library is not installed, or if the installed version +is less than a given minimum version, the function will return None. +Otherwise, it will return the library. See the docstring of +import_module() for more information. + +""" + +from sympy.external.importtools import import_module + +__all__ = ['import_module'] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/gmpy.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/gmpy.py new file mode 100644 index 0000000000000000000000000000000000000000..d26942864bf4786e72198d3640d488857b3313f4 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/gmpy.py @@ -0,0 +1,342 @@ +from __future__ import annotations +import os +from ctypes import c_long, sizeof +from functools import reduce +from typing import Type +from warnings import warn + +from sympy.external import import_module + +from .pythonmpq import PythonMPQ + +from .ntheory import ( + bit_scan1 as python_bit_scan1, + bit_scan0 as python_bit_scan0, + remove as python_remove, + factorial as python_factorial, + sqrt as python_sqrt, + sqrtrem as python_sqrtrem, + gcd as python_gcd, + lcm as python_lcm, + gcdext as python_gcdext, + is_square as python_is_square, + invert as python_invert, + legendre as python_legendre, + jacobi as python_jacobi, + kronecker as python_kronecker, + iroot as python_iroot, + is_fermat_prp as python_is_fermat_prp, + is_euler_prp as python_is_euler_prp, + is_strong_prp as python_is_strong_prp, + is_fibonacci_prp as python_is_fibonacci_prp, + is_lucas_prp as python_is_lucas_prp, + is_selfridge_prp as python_is_selfridge_prp, + is_strong_lucas_prp as python_is_strong_lucas_prp, + is_strong_selfridge_prp as python_is_strong_selfridge_prp, + is_bpsw_prp as python_is_bpsw_prp, + is_strong_bpsw_prp as python_is_strong_bpsw_prp, +) + + +__all__ = [ + # GROUND_TYPES is either 'gmpy' or 'python' depending on which is used. If + # gmpy is installed then it will be used unless the environment variable + # SYMPY_GROUND_TYPES is set to something other than 'auto', 'gmpy', or + # 'gmpy2'. + 'GROUND_TYPES', + + # If HAS_GMPY is 0, no supported version of gmpy is available. Otherwise, + # HAS_GMPY will be 2 for gmpy2 if GROUND_TYPES is 'gmpy'. It used to be + # possible for HAS_GMPY to be 1 for gmpy but gmpy is no longer supported. + 'HAS_GMPY', + + # SYMPY_INTS is a tuple containing the base types for valid integer types. + # This is either (int,) or (int, type(mpz(0))) depending on GROUND_TYPES. + 'SYMPY_INTS', + + # MPQ is either gmpy.mpq or the Python equivalent from + # sympy.external.pythonmpq + 'MPQ', + + # MPZ is either gmpy.mpz or int. + 'MPZ', + + 'bit_scan1', + 'bit_scan0', + 'remove', + 'factorial', + 'sqrt', + 'is_square', + 'sqrtrem', + 'gcd', + 'lcm', + 'gcdext', + 'invert', + 'legendre', + 'jacobi', + 'kronecker', + 'iroot', + 'is_fermat_prp', + 'is_euler_prp', + 'is_strong_prp', + 'is_fibonacci_prp', + 'is_lucas_prp', + 'is_selfridge_prp', + 'is_strong_lucas_prp', + 'is_strong_selfridge_prp', + 'is_bpsw_prp', + 'is_strong_bpsw_prp', +] + + +# +# Tested python-flint version. Future versions might work but we will only use +# them if explicitly requested by SYMPY_GROUND_TYPES=flint. +# +_PYTHON_FLINT_VERSION_NEEDED = ["0.6", "0.7", "0.8", "0.9", "0.10"] + + +def _flint_version_okay(flint_version): + major, minor = flint_version.split('.')[:2] + flint_ver = f'{major}.{minor}' + return flint_ver in _PYTHON_FLINT_VERSION_NEEDED + +# +# We will only use gmpy2 >= 2.0.0 +# +_GMPY2_MIN_VERSION = '2.0.0' + + +def _get_flint(sympy_ground_types): + if sympy_ground_types not in ('auto', 'flint'): + return None + + try: + import flint + # Earlier versions of python-flint may not have __version__. + from flint import __version__ as _flint_version + except ImportError: + if sympy_ground_types == 'flint': + warn("SYMPY_GROUND_TYPES was set to flint but python-flint is not " + "installed. Falling back to other ground types.") + return None + + if _flint_version_okay(_flint_version): + return flint + elif sympy_ground_types == 'auto': + return None + else: + warn(f"Using python-flint {_flint_version} because SYMPY_GROUND_TYPES " + f"is set to flint but this version of SymPy is only tested " + f"with python-flint versions {_PYTHON_FLINT_VERSION_NEEDED}.") + return flint + + +def _get_gmpy2(sympy_ground_types): + if sympy_ground_types not in ('auto', 'gmpy', 'gmpy2'): + return None + + gmpy = import_module('gmpy2', min_module_version=_GMPY2_MIN_VERSION, + module_version_attr='version', module_version_attr_call_args=()) + + if sympy_ground_types != 'auto' and gmpy is None: + warn("gmpy2 library is not installed, switching to 'python' ground types") + + return gmpy + + +# +# SYMPY_GROUND_TYPES can be flint, gmpy, gmpy2, python or auto (default) +# +_SYMPY_GROUND_TYPES = os.environ.get('SYMPY_GROUND_TYPES', 'auto').lower() +_flint = None +_gmpy = None + +# +# First handle auto-detection of flint/gmpy2. We will prefer flint if available +# or otherwise gmpy2 if available and then lastly the python types. +# +if _SYMPY_GROUND_TYPES in ('auto', 'flint'): + _flint = _get_flint(_SYMPY_GROUND_TYPES) + if _flint is not None: + _SYMPY_GROUND_TYPES = 'flint' + else: + _SYMPY_GROUND_TYPES = 'auto' + +if _SYMPY_GROUND_TYPES in ('auto', 'gmpy', 'gmpy2'): + _gmpy = _get_gmpy2(_SYMPY_GROUND_TYPES) + if _gmpy is not None: + _SYMPY_GROUND_TYPES = 'gmpy' + else: + _SYMPY_GROUND_TYPES = 'python' + +if _SYMPY_GROUND_TYPES not in ('flint', 'gmpy', 'python'): + warn("SYMPY_GROUND_TYPES environment variable unrecognised. " + "Should be 'auto', 'flint', 'gmpy', 'gmpy2' or 'python'.") + _SYMPY_GROUND_TYPES = 'python' + +# +# At this point _SYMPY_GROUND_TYPES is either flint, gmpy or python. The blocks +# below define the values exported by this module in each case. +# + +# +# In gmpy2 and flint, there are functions that take a long (or unsigned long) +# argument. That is, it is not possible to input a value larger than that. +# +LONG_MAX = (1 << (8*sizeof(c_long) - 1)) - 1 + +# +# Type checkers are confused by what SYMPY_INTS is. There may be a better type +# hint for this like Type[Integral] or something. +# +SYMPY_INTS: tuple[Type, ...] + +if _SYMPY_GROUND_TYPES == 'gmpy': + + assert _gmpy is not None + + flint = None + gmpy = _gmpy + + HAS_GMPY = 2 + GROUND_TYPES = 'gmpy' + SYMPY_INTS = (int, type(gmpy.mpz(0))) + MPZ = gmpy.mpz + MPQ = gmpy.mpq + + bit_scan1 = gmpy.bit_scan1 + bit_scan0 = gmpy.bit_scan0 + remove = gmpy.remove + factorial = gmpy.fac + sqrt = gmpy.isqrt + is_square = gmpy.is_square + sqrtrem = gmpy.isqrt_rem + gcd = gmpy.gcd + lcm = gmpy.lcm + gcdext = gmpy.gcdext + invert = gmpy.invert + legendre = gmpy.legendre + jacobi = gmpy.jacobi + kronecker = gmpy.kronecker + + def iroot(x, n): + # In the latest gmpy2, the threshold for n is ULONG_MAX, + # but adjust to the older one. + if n <= LONG_MAX: + return gmpy.iroot(x, n) + return python_iroot(x, n) + + is_fermat_prp = gmpy.is_fermat_prp + is_euler_prp = gmpy.is_euler_prp + is_strong_prp = gmpy.is_strong_prp + is_fibonacci_prp = gmpy.is_fibonacci_prp + is_lucas_prp = gmpy.is_lucas_prp + is_selfridge_prp = gmpy.is_selfridge_prp + is_strong_lucas_prp = gmpy.is_strong_lucas_prp + is_strong_selfridge_prp = gmpy.is_strong_selfridge_prp + is_bpsw_prp = gmpy.is_bpsw_prp + is_strong_bpsw_prp = gmpy.is_strong_bpsw_prp + +elif _SYMPY_GROUND_TYPES == 'flint': + + assert _flint is not None + + flint = _flint + gmpy = None + + HAS_GMPY = 0 + GROUND_TYPES = 'flint' + SYMPY_INTS = (int, flint.fmpz) # type: ignore + MPZ = flint.fmpz # type: ignore + MPQ = flint.fmpq # type: ignore + + bit_scan1 = python_bit_scan1 + bit_scan0 = python_bit_scan0 + remove = python_remove + factorial = python_factorial + + def sqrt(x): + return flint.fmpz(x).isqrt() + + def is_square(x): + if x < 0: + return False + return flint.fmpz(x).sqrtrem()[1] == 0 + + def sqrtrem(x): + return flint.fmpz(x).sqrtrem() + + def gcd(*args): + return reduce(flint.fmpz.gcd, args, flint.fmpz(0)) + + def lcm(*args): + return reduce(flint.fmpz.lcm, args, flint.fmpz(1)) + + gcdext = python_gcdext + invert = python_invert + legendre = python_legendre + + def jacobi(x, y): + if y <= 0 or not y % 2: + raise ValueError("y should be an odd positive integer") + return flint.fmpz(x).jacobi(y) + + kronecker = python_kronecker + + def iroot(x, n): + if n <= LONG_MAX: + y = flint.fmpz(x).root(n) + return y, y**n == x + return python_iroot(x, n) + + is_fermat_prp = python_is_fermat_prp + is_euler_prp = python_is_euler_prp + is_strong_prp = python_is_strong_prp + is_fibonacci_prp = python_is_fibonacci_prp + is_lucas_prp = python_is_lucas_prp + is_selfridge_prp = python_is_selfridge_prp + is_strong_lucas_prp = python_is_strong_lucas_prp + is_strong_selfridge_prp = python_is_strong_selfridge_prp + is_bpsw_prp = python_is_bpsw_prp + is_strong_bpsw_prp = python_is_strong_bpsw_prp + +elif _SYMPY_GROUND_TYPES == 'python': + + flint = None + gmpy = None + + HAS_GMPY = 0 + GROUND_TYPES = 'python' + SYMPY_INTS = (int,) + MPZ = int + MPQ = PythonMPQ + + bit_scan1 = python_bit_scan1 + bit_scan0 = python_bit_scan0 + remove = python_remove + factorial = python_factorial + sqrt = python_sqrt + is_square = python_is_square + sqrtrem = python_sqrtrem + gcd = python_gcd + lcm = python_lcm + gcdext = python_gcdext + invert = python_invert + legendre = python_legendre + jacobi = python_jacobi + kronecker = python_kronecker + iroot = python_iroot + is_fermat_prp = python_is_fermat_prp + is_euler_prp = python_is_euler_prp + is_strong_prp = python_is_strong_prp + is_fibonacci_prp = python_is_fibonacci_prp + is_lucas_prp = python_is_lucas_prp + is_selfridge_prp = python_is_selfridge_prp + is_strong_lucas_prp = python_is_strong_lucas_prp + is_strong_selfridge_prp = python_is_strong_selfridge_prp + is_bpsw_prp = python_is_bpsw_prp + is_strong_bpsw_prp = python_is_strong_bpsw_prp + +else: + assert False diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/importtools.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/importtools.py new file mode 100644 index 0000000000000000000000000000000000000000..5008b3dd4634d3cee10744a0a92b1204051f07cc --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/importtools.py @@ -0,0 +1,187 @@ +"""Tools to assist importing optional external modules.""" + +import sys +import re + +# Override these in the module to change the default warning behavior. +# For example, you might set both to False before running the tests so that +# warnings are not printed to the console, or set both to True for debugging. + +WARN_NOT_INSTALLED = None # Default is False +WARN_OLD_VERSION = None # Default is True + + +def __sympy_debug(): + # helper function from sympy/__init__.py + # We don't just import SYMPY_DEBUG from that file because we don't want to + # import all of SymPy just to use this module. + import os + debug_str = os.getenv('SYMPY_DEBUG', 'False') + if debug_str in ('True', 'False'): + return eval(debug_str) + else: + raise RuntimeError("unrecognized value for SYMPY_DEBUG: %s" % + debug_str) + +if __sympy_debug(): + WARN_OLD_VERSION = True + WARN_NOT_INSTALLED = True + + +_component_re = re.compile(r'(\d+ | [a-z]+ | \.)', re.VERBOSE) + +def version_tuple(vstring): + # Parse a version string to a tuple e.g. '1.2' -> (1, 2) + # Simplified from distutils.version.LooseVersion which was deprecated in + # Python 3.10. + components = [] + for x in _component_re.split(vstring): + if x and x != '.': + try: + x = int(x) + except ValueError: + pass + components.append(x) + return tuple(components) + + +def import_module(module, min_module_version=None, min_python_version=None, + warn_not_installed=None, warn_old_version=None, + module_version_attr='__version__', module_version_attr_call_args=None, + import_kwargs={}, catch=()): + """ + Import and return a module if it is installed. + + If the module is not installed, it returns None. + + A minimum version for the module can be given as the keyword argument + min_module_version. This should be comparable against the module version. + By default, module.__version__ is used to get the module version. To + override this, set the module_version_attr keyword argument. If the + attribute of the module to get the version should be called (e.g., + module.version()), then set module_version_attr_call_args to the args such + that module.module_version_attr(*module_version_attr_call_args) returns the + module's version. + + If the module version is less than min_module_version using the Python < + comparison, None will be returned, even if the module is installed. You can + use this to keep from importing an incompatible older version of a module. + + You can also specify a minimum Python version by using the + min_python_version keyword argument. This should be comparable against + sys.version_info. + + If the keyword argument warn_not_installed is set to True, the function will + emit a UserWarning when the module is not installed. + + If the keyword argument warn_old_version is set to True, the function will + emit a UserWarning when the library is installed, but cannot be imported + because of the min_module_version or min_python_version options. + + Note that because of the way warnings are handled, a warning will be + emitted for each module only once. You can change the default warning + behavior by overriding the values of WARN_NOT_INSTALLED and WARN_OLD_VERSION + in sympy.external.importtools. By default, WARN_NOT_INSTALLED is False and + WARN_OLD_VERSION is True. + + This function uses __import__() to import the module. To pass additional + options to __import__(), use the import_kwargs keyword argument. For + example, to import a submodule A.B, you must pass a nonempty fromlist option + to __import__. See the docstring of __import__(). + + This catches ImportError to determine if the module is not installed. To + catch additional errors, pass them as a tuple to the catch keyword + argument. + + Examples + ======== + + >>> from sympy.external import import_module + + >>> numpy = import_module('numpy') + + >>> numpy = import_module('numpy', min_python_version=(2, 7), + ... warn_old_version=False) + + >>> numpy = import_module('numpy', min_module_version='1.5', + ... warn_old_version=False) # numpy.__version__ is a string + + >>> # gmpy does not have __version__, but it does have gmpy.version() + + >>> gmpy = import_module('gmpy', min_module_version='1.14', + ... module_version_attr='version', module_version_attr_call_args=(), + ... warn_old_version=False) + + >>> # To import a submodule, you must pass a nonempty fromlist to + >>> # __import__(). The values do not matter. + >>> p3 = import_module('mpl_toolkits.mplot3d', + ... import_kwargs={'fromlist':['something']}) + + >>> # matplotlib.pyplot can raise RuntimeError when the display cannot be opened + >>> matplotlib = import_module('matplotlib', + ... import_kwargs={'fromlist':['pyplot']}, catch=(RuntimeError,)) + + """ + # keyword argument overrides default, and global variable overrides + # keyword argument. + warn_old_version = (WARN_OLD_VERSION if WARN_OLD_VERSION is not None + else warn_old_version or True) + warn_not_installed = (WARN_NOT_INSTALLED if WARN_NOT_INSTALLED is not None + else warn_not_installed or False) + + import warnings + + # Check Python first so we don't waste time importing a module we can't use + if min_python_version: + if sys.version_info < min_python_version: + if warn_old_version: + warnings.warn("Python version is too old to use %s " + "(%s or newer required)" % ( + module, '.'.join(map(str, min_python_version))), + UserWarning, stacklevel=2) + return + + try: + mod = __import__(module, **import_kwargs) + + ## there's something funny about imports with matplotlib and py3k. doing + ## from matplotlib import collections + ## gives python's stdlib collections module. explicitly re-importing + ## the module fixes this. + from_list = import_kwargs.get('fromlist', ()) + for submod in from_list: + if submod == 'collections' and mod.__name__ == 'matplotlib': + __import__(module + '.' + submod) + except ImportError: + if warn_not_installed: + warnings.warn("%s module is not installed" % module, UserWarning, + stacklevel=2) + return + except catch as e: + if warn_not_installed: + warnings.warn( + "%s module could not be used (%s)" % (module, repr(e)), + stacklevel=2) + return + + if min_module_version: + modversion = getattr(mod, module_version_attr) + if module_version_attr_call_args is not None: + modversion = modversion(*module_version_attr_call_args) + if version_tuple(modversion) < version_tuple(min_module_version): + if warn_old_version: + # Attempt to create a pretty string version of the version + if isinstance(min_module_version, str): + verstr = min_module_version + elif isinstance(min_module_version, (tuple, list)): + verstr = '.'.join(map(str, min_module_version)) + else: + # Either don't know what this is. Hopefully + # it's something that has a nice str version, like an int. + verstr = str(min_module_version) + warnings.warn("%s version is too old to use " + "(%s or newer required)" % (module, verstr), + UserWarning, stacklevel=2) + return + + return mod diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/ntheory.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/ntheory.py new file mode 100644 index 0000000000000000000000000000000000000000..a0c9bf813cf02b311f9a12ee7fbc4932ed551f3b --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/ntheory.py @@ -0,0 +1,618 @@ +# sympy.external.ntheory +# +# This module provides pure Python implementations of some number theory +# functions that are alternately used from gmpy2 if it is installed. + +import math + +import mpmath.libmp as mlib + + +_small_trailing = [0] * 256 +for j in range(1, 8): + _small_trailing[1 << j :: 1 << (j + 1)] = [j] * (1 << (7 - j)) + + +def bit_scan1(x, n=0): + if not x: + return + x = abs(x >> n) + low_byte = x & 0xFF + if low_byte: + return _small_trailing[low_byte] + n + + t = 8 + n + x >>= 8 + # 2**m is quick for z up through 2**30 + z = x.bit_length() - 1 + if x == 1 << z: + return z + t + + if z < 300: + # fixed 8-byte reduction + while not x & 0xFF: + x >>= 8 + t += 8 + else: + # binary reduction important when there might be a large + # number of trailing 0s + p = z >> 1 + while not x & 0xFF: + while x & ((1 << p) - 1): + p >>= 1 + x >>= p + t += p + return t + _small_trailing[x & 0xFF] + + +def bit_scan0(x, n=0): + return bit_scan1(x + (1 << n), n) + + +def remove(x, f): + if f < 2: + raise ValueError("factor must be > 1") + if x == 0: + return 0, 0 + if f == 2: + b = bit_scan1(x) + return x >> b, b + m = 0 + y, rem = divmod(x, f) + while not rem: + x = y + m += 1 + if m > 5: + pow_list = [f**2] + while pow_list: + _f = pow_list[-1] + y, rem = divmod(x, _f) + if not rem: + m += 1 << len(pow_list) + x = y + pow_list.append(_f**2) + else: + pow_list.pop() + y, rem = divmod(x, f) + return x, m + + +def factorial(x): + """Return x!.""" + return int(mlib.ifac(int(x))) + + +def sqrt(x): + """Integer square root of x.""" + return int(mlib.isqrt(int(x))) + + +def sqrtrem(x): + """Integer square root of x and remainder.""" + s, r = mlib.sqrtrem(int(x)) + return (int(s), int(r)) + + +gcd = math.gcd +lcm = math.lcm + + +def _sign(n): + if n < 0: + return -1, -n + return 1, n + + +def gcdext(a, b): + if not a or not b: + g = abs(a) or abs(b) + if not g: + return (0, 0, 0) + return (g, a // g, b // g) + + x_sign, a = _sign(a) + y_sign, b = _sign(b) + x, r = 1, 0 + y, s = 0, 1 + + while b: + q, c = divmod(a, b) + a, b = b, c + x, r = r, x - q*r + y, s = s, y - q*s + + return (a, x * x_sign, y * y_sign) + + +def is_square(x): + """Return True if x is a square number.""" + if x < 0: + return False + + # Note that the possible values of y**2 % n for a given n are limited. + # For example, when n=4, y**2 % n can only take 0 or 1. + # In other words, if x % 4 is 2 or 3, then x is not a square number. + # Mathematically, it determines if it belongs to the set {y**2 % n}, + # but implementationally, it can be realized as a logical conjunction + # with an n-bit integer. + # see https://mersenneforum.org/showpost.php?p=110896 + # def magic(n): + # s = {y**2 % n for y in range(n)} + # s = set(range(n)) - s + # return sum(1 << bit for bit in s) + # >>> print(hex(magic(128))) + # 0xfdfdfdedfdfdfdecfdfdfdedfdfcfdec + # >>> print(hex(magic(99))) + # 0x5f6f9ffb6fb7ddfcb75befdec + # >>> print(hex(magic(91))) + # 0x6fd1bfcfed5f3679d3ebdec + # >>> print(hex(magic(85))) + # 0xdef9ae771ffe3b9d67dec + if 0xfdfdfdedfdfdfdecfdfdfdedfdfcfdec & (1 << (x & 127)): + return False # e.g. 2, 3 + m = x % 765765 # 765765 = 99 * 91 * 85 + if 0x5f6f9ffb6fb7ddfcb75befdec & (1 << (m % 99)): + return False # e.g. 17, 68 + if 0x6fd1bfcfed5f3679d3ebdec & (1 << (m % 91)): + return False # e.g. 97, 388 + if 0xdef9ae771ffe3b9d67dec & (1 << (m % 85)): + return False # e.g. 793, 1408 + return mlib.sqrtrem(int(x))[1] == 0 + + +def invert(x, m): + """Modular inverse of x modulo m. + + Returns y such that x*y == 1 mod m. + + Uses ``math.pow`` but reproduces the behaviour of ``gmpy2.invert`` + which raises ZeroDivisionError if no inverse exists. + """ + try: + return pow(x, -1, m) + except ValueError: + raise ZeroDivisionError("invert() no inverse exists") + + +def legendre(x, y): + """Legendre symbol (x / y). + + Following the implementation of gmpy2, + the error is raised only when y is an even number. + """ + if y <= 0 or not y % 2: + raise ValueError("y should be an odd prime") + x %= y + if not x: + return 0 + if pow(x, (y - 1) // 2, y) == 1: + return 1 + return -1 + + +def jacobi(x, y): + """Jacobi symbol (x / y).""" + if y <= 0 or not y % 2: + raise ValueError("y should be an odd positive integer") + x %= y + if not x: + return int(y == 1) + if y == 1 or x == 1: + return 1 + if gcd(x, y) != 1: + return 0 + j = 1 + while x != 0: + while x % 2 == 0 and x > 0: + x >>= 1 + if y % 8 in [3, 5]: + j = -j + x, y = y, x + if x % 4 == y % 4 == 3: + j = -j + x %= y + return j + + +def kronecker(x, y): + """Kronecker symbol (x / y).""" + if gcd(x, y) != 1: + return 0 + if y == 0: + return 1 + sign = -1 if y < 0 and x < 0 else 1 + y = abs(y) + s = bit_scan1(y) + y >>= s + if s % 2 and x % 8 in [3, 5]: + sign = -sign + return sign * jacobi(x, y) + + +def iroot(y, n): + if y < 0: + raise ValueError("y must be nonnegative") + if n < 1: + raise ValueError("n must be positive") + if y in (0, 1): + return y, True + if n == 1: + return y, True + if n == 2: + x, rem = mlib.sqrtrem(y) + return int(x), not rem + if n >= y.bit_length(): + return 1, False + # Get initial estimate for Newton's method. Care must be taken to + # avoid overflow + try: + guess = int(y**(1./n) + 0.5) + except OverflowError: + exp = math.log2(y)/n + if exp > 53: + shift = int(exp - 53) + guess = int(2.0**(exp - shift) + 1) << shift + else: + guess = int(2.0**exp) + if guess > 2**50: + # Newton iteration + xprev, x = -1, guess + while 1: + t = x**(n - 1) + xprev, x = x, ((n - 1)*x + y//t)//n + if abs(x - xprev) < 2: + break + else: + x = guess + # Compensate + t = x**n + while t < y: + x += 1 + t = x**n + while t > y: + x -= 1 + t = x**n + return x, t == y + + +def is_fermat_prp(n, a): + if a < 2: + raise ValueError("is_fermat_prp() requires 'a' greater than or equal to 2") + if n < 1: + raise ValueError("is_fermat_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + a %= n + if gcd(n, a) != 1: + raise ValueError("is_fermat_prp() requires gcd(n,a) == 1") + return pow(a, n - 1, n) == 1 + + +def is_euler_prp(n, a): + if a < 2: + raise ValueError("is_euler_prp() requires 'a' greater than or equal to 2") + if n < 1: + raise ValueError("is_euler_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + a %= n + if gcd(n, a) != 1: + raise ValueError("is_euler_prp() requires gcd(n,a) == 1") + return pow(a, n >> 1, n) == jacobi(a, n) % n + + +def _is_strong_prp(n, a): + s = bit_scan1(n - 1) + a = pow(a, n >> s, n) + if a == 1 or a == n - 1: + return True + for _ in range(s - 1): + a = pow(a, 2, n) + if a == n - 1: + return True + if a == 1: + return False + return False + + +def is_strong_prp(n, a): + if a < 2: + raise ValueError("is_strong_prp() requires 'a' greater than or equal to 2") + if n < 1: + raise ValueError("is_strong_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + a %= n + if gcd(n, a) != 1: + raise ValueError("is_strong_prp() requires gcd(n,a) == 1") + return _is_strong_prp(n, a) + + +def _lucas_sequence(n, P, Q, k): + r"""Return the modular Lucas sequence (U_k, V_k, Q_k). + + Explanation + =========== + + Given a Lucas sequence defined by P, Q, returns the kth values for + U and V, along with Q^k, all modulo n. This is intended for use with + possibly very large values of n and k, where the combinatorial functions + would be completely unusable. + + .. math :: + U_k = \begin{cases} + 0 & \text{if } k = 0\\ + 1 & \text{if } k = 1\\ + PU_{k-1} - QU_{k-2} & \text{if } k > 1 + \end{cases}\\ + V_k = \begin{cases} + 2 & \text{if } k = 0\\ + P & \text{if } k = 1\\ + PV_{k-1} - QV_{k-2} & \text{if } k > 1 + \end{cases} + + The modular Lucas sequences are used in numerous places in number theory, + especially in the Lucas compositeness tests and the various n + 1 proofs. + + Parameters + ========== + + n : int + n is an odd number greater than or equal to 3 + P : int + Q : int + D determined by D = P**2 - 4*Q is non-zero + k : int + k is a nonnegative integer + + Returns + ======= + + U, V, Qk : (int, int, int) + `(U_k \bmod{n}, V_k \bmod{n}, Q^k \bmod{n})` + + Examples + ======== + + >>> from sympy.external.ntheory import _lucas_sequence + >>> N = 10**2000 + 4561 + >>> sol = U, V, Qk = _lucas_sequence(N, 3, 1, N//2); sol + (0, 2, 1) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Lucas_sequence + + """ + if k == 0: + return (0, 2, 1) + D = P**2 - 4*Q + U = 1 + V = P + Qk = Q % n + if Q == 1: + # Optimization for extra strong tests. + for b in bin(k)[3:]: + U = (U*V) % n + V = (V*V - 2) % n + if b == "1": + U, V = U*P + V, V*P + U*D + if U & 1: + U += n + if V & 1: + V += n + U, V = U >> 1, V >> 1 + elif P == 1 and Q == -1: + # Small optimization for 50% of Selfridge parameters. + for b in bin(k)[3:]: + U = (U*V) % n + if Qk == 1: + V = (V*V - 2) % n + else: + V = (V*V + 2) % n + Qk = 1 + if b == "1": + # new_U = (U + V) // 2 + # new_V = (5*U + V) // 2 = 2*U + new_U + U, V = U + V, U << 1 + if U & 1: + U += n + U >>= 1 + V += U + Qk = -1 + Qk %= n + elif P == 1: + for b in bin(k)[3:]: + U = (U*V) % n + V = (V*V - 2*Qk) % n + Qk *= Qk + if b == "1": + # new_U = (U + V) // 2 + # new_V = new_U - 2*Q*U + U, V = U + V, (Q*U) << 1 + if U & 1: + U += n + U >>= 1 + V = U - V + Qk *= Q + Qk %= n + else: + # The general case with any P and Q. + for b in bin(k)[3:]: + U = (U*V) % n + V = (V*V - 2*Qk) % n + Qk *= Qk + if b == "1": + U, V = U*P + V, V*P + U*D + if U & 1: + U += n + if V & 1: + V += n + U, V = U >> 1, V >> 1 + Qk *= Q + Qk %= n + return (U % n, V % n, Qk) + + +def is_fibonacci_prp(n, p, q): + d = p**2 - 4*q + if d == 0 or p <= 0 or q not in [1, -1]: + raise ValueError("invalid values for p,q in is_fibonacci_prp()") + if n < 1: + raise ValueError("is_fibonacci_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + return _lucas_sequence(n, p, q, n)[1] == p % n + + +def is_lucas_prp(n, p, q): + d = p**2 - 4*q + if d == 0: + raise ValueError("invalid values for p,q in is_lucas_prp()") + if n < 1: + raise ValueError("is_lucas_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + if gcd(n, q*d) not in [1, n]: + raise ValueError("is_lucas_prp() requires gcd(n,2*q*D) == 1") + return _lucas_sequence(n, p, q, n - jacobi(d, n))[0] == 0 + + +def _is_selfridge_prp(n): + """Lucas compositeness test with the Selfridge parameters for n. + + Explanation + =========== + + The Lucas compositeness test checks whether n is a prime number. + The test can be run with arbitrary parameters ``P`` and ``Q``, which also change the performance of the test. + So, which parameters are most effective for running the Lucas compositeness test? + As an algorithm for determining ``P`` and ``Q``, Selfridge proposed method A [1]_ page 1401 + (Since two methods were proposed, referred to simply as A and B in the paper, + we will refer to one of them as "method A"). + + method A fixes ``P = 1``. Then, ``D`` defined by ``D = P**2 - 4Q`` is varied from 5, -7, 9, -11, 13, and so on, + with the first ``D`` being ``jacobi(D, n) == -1``. Once ``D`` is determined, + ``Q`` is determined to be ``(P**2 - D)//4``. + + References + ========== + + .. [1] Robert Baillie, Samuel S. Wagstaff, Lucas Pseudoprimes, + Math. Comp. Vol 35, Number 152 (1980), pp. 1391-1417, + https://doi.org/10.1090%2FS0025-5718-1980-0583518-6 + http://mpqs.free.fr/LucasPseudoprimes.pdf + + """ + for D in range(5, 1_000_000, 2): + if D & 2: # if D % 4 == 3 + D = -D + j = jacobi(D, n) + if j == -1: + return _lucas_sequence(n, 1, (1-D) // 4, n + 1)[0] == 0 + if j == 0 and D % n: + return False + # When j == -1 is hard to find, suspect a square number + if D == 13 and is_square(n): + return False + raise ValueError("appropriate value for D cannot be found in is_selfridge_prp()") + + +def is_selfridge_prp(n): + if n < 1: + raise ValueError("is_selfridge_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + return _is_selfridge_prp(n) + + +def is_strong_lucas_prp(n, p, q): + D = p**2 - 4*q + if D == 0: + raise ValueError("invalid values for p,q in is_strong_lucas_prp()") + if n < 1: + raise ValueError("is_selfridge_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + if gcd(n, q*D) not in [1, n]: + raise ValueError("is_strong_lucas_prp() requires gcd(n,2*q*D) == 1") + j = jacobi(D, n) + s = bit_scan1(n - j) + U, V, Qk = _lucas_sequence(n, p, q, (n - j) >> s) + if U == 0 or V == 0: + return True + for _ in range(s - 1): + V = (V*V - 2*Qk) % n + if V == 0: + return True + Qk = pow(Qk, 2, n) + return False + + +def _is_strong_selfridge_prp(n): + for D in range(5, 1_000_000, 2): + if D & 2: # if D % 4 == 3 + D = -D + j = jacobi(D, n) + if j == -1: + s = bit_scan1(n + 1) + U, V, Qk = _lucas_sequence(n, 1, (1-D) // 4, (n + 1) >> s) + if U == 0 or V == 0: + return True + for _ in range(s - 1): + V = (V*V - 2*Qk) % n + if V == 0: + return True + Qk = pow(Qk, 2, n) + return False + if j == 0 and D % n: + return False + # When j == -1 is hard to find, suspect a square number + if D == 13 and is_square(n): + return False + raise ValueError("appropriate value for D cannot be found in is_strong_selfridge_prp()") + + +def is_strong_selfridge_prp(n): + if n < 1: + raise ValueError("is_strong_selfridge_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + return _is_strong_selfridge_prp(n) + + +def is_bpsw_prp(n): + if n < 1: + raise ValueError("is_bpsw_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + return _is_strong_prp(n, 2) and _is_selfridge_prp(n) + + +def is_strong_bpsw_prp(n): + if n < 1: + raise ValueError("is_strong_bpsw_prp() requires 'n' be greater than 0") + if n == 1: + return False + if n % 2 == 0: + return n == 2 + return _is_strong_prp(n, 2) and _is_strong_selfridge_prp(n) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/pythonmpq.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/pythonmpq.py new file mode 100644 index 0000000000000000000000000000000000000000..4f2d102974e04e139c00a39057976b5a5bf90776 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/pythonmpq.py @@ -0,0 +1,341 @@ +""" +PythonMPQ: Rational number type based on Python integers. + +This class is intended as a pure Python fallback for when gmpy2 is not +installed. If gmpy2 is installed then its mpq type will be used instead. The +mpq type is around 20x faster. We could just use the stdlib Fraction class +here but that is slower: + + from fractions import Fraction + from sympy.external.pythonmpq import PythonMPQ + nums = range(1000) + dens = range(5, 1005) + rats = [Fraction(n, d) for n, d in zip(nums, dens)] + sum(rats) # <--- 24 milliseconds + rats = [PythonMPQ(n, d) for n, d in zip(nums, dens)] + sum(rats) # <--- 7 milliseconds + +Both mpq and Fraction have some awkward features like the behaviour of +division with // and %: + + >>> from fractions import Fraction + >>> Fraction(2, 3) % Fraction(1, 4) + 1/6 + +For the QQ domain we do not want this behaviour because there should be no +remainder when dividing rational numbers. SymPy does not make use of this +aspect of mpq when gmpy2 is installed. Since this class is a fallback for that +case we do not bother implementing e.g. __mod__ so that we can be sure we +are not using it when gmpy2 is installed either. +""" + +from __future__ import annotations +import operator +from math import gcd +from decimal import Decimal +from fractions import Fraction +import sys +from typing import Type + + +# Used for __hash__ +_PyHASH_MODULUS = sys.hash_info.modulus +_PyHASH_INF = sys.hash_info.inf + + +class PythonMPQ: + """Rational number implementation that is intended to be compatible with + gmpy2's mpq. + + Also slightly faster than fractions.Fraction. + + PythonMPQ should be treated as immutable although no effort is made to + prevent mutation (since that might slow down calculations). + """ + __slots__ = ('numerator', 'denominator') + + def __new__(cls, numerator, denominator=None): + """Construct PythonMPQ with gcd computation and checks""" + if denominator is not None: + # + # PythonMPQ(n, d): require n and d to be int and d != 0 + # + if isinstance(numerator, int) and isinstance(denominator, int): + # This is the slow part: + divisor = gcd(numerator, denominator) + numerator //= divisor + denominator //= divisor + return cls._new_check(numerator, denominator) + else: + # + # PythonMPQ(q) + # + # Here q can be PythonMPQ, int, Decimal, float, Fraction or str + # + if isinstance(numerator, int): + return cls._new(numerator, 1) + elif isinstance(numerator, PythonMPQ): + return cls._new(numerator.numerator, numerator.denominator) + + # Let Fraction handle Decimal/float conversion and str parsing + if isinstance(numerator, (Decimal, float, str)): + numerator = Fraction(numerator) + if isinstance(numerator, Fraction): + return cls._new(numerator.numerator, numerator.denominator) + # + # Reject everything else. This is more strict than mpq which allows + # things like mpq(Fraction, Fraction) or mpq(Decimal, any). The mpq + # behaviour is somewhat inconsistent so we choose to accept only a + # more strict subset of what mpq allows. + # + raise TypeError("PythonMPQ() requires numeric or string argument") + + @classmethod + def _new_check(cls, numerator, denominator): + """Construct PythonMPQ, check divide by zero and canonicalize signs""" + if not denominator: + raise ZeroDivisionError(f'Zero divisor {numerator}/{denominator}') + elif denominator < 0: + numerator = -numerator + denominator = -denominator + return cls._new(numerator, denominator) + + @classmethod + def _new(cls, numerator, denominator): + """Construct PythonMPQ efficiently (no checks)""" + obj = super().__new__(cls) + obj.numerator = numerator + obj.denominator = denominator + return obj + + def __int__(self): + """Convert to int (truncates towards zero)""" + p, q = self.numerator, self.denominator + if p < 0: + return -(-p//q) + return p//q + + def __float__(self): + """Convert to float (approximately)""" + return self.numerator / self.denominator + + def __bool__(self): + """True/False if nonzero/zero""" + return bool(self.numerator) + + def __eq__(self, other): + """Compare equal with PythonMPQ, int, float, Decimal or Fraction""" + if isinstance(other, PythonMPQ): + return (self.numerator == other.numerator + and self.denominator == other.denominator) + elif isinstance(other, self._compatible_types): + return self.__eq__(PythonMPQ(other)) + else: + return NotImplemented + + def __hash__(self): + """hash - same as mpq/Fraction""" + try: + dinv = pow(self.denominator, -1, _PyHASH_MODULUS) + except ValueError: + hash_ = _PyHASH_INF + else: + hash_ = hash(hash(abs(self.numerator)) * dinv) + result = hash_ if self.numerator >= 0 else -hash_ + return -2 if result == -1 else result + + def __reduce__(self): + """Deconstruct for pickling""" + return type(self), (self.numerator, self.denominator) + + def __str__(self): + """Convert to string""" + if self.denominator != 1: + return f"{self.numerator}/{self.denominator}" + else: + return f"{self.numerator}" + + def __repr__(self): + """Convert to string""" + return f"MPQ({self.numerator},{self.denominator})" + + def _cmp(self, other, op): + """Helper for lt/le/gt/ge""" + if not isinstance(other, self._compatible_types): + return NotImplemented + lhs = self.numerator * other.denominator + rhs = other.numerator * self.denominator + return op(lhs, rhs) + + def __lt__(self, other): + """self < other""" + return self._cmp(other, operator.lt) + + def __le__(self, other): + """self <= other""" + return self._cmp(other, operator.le) + + def __gt__(self, other): + """self > other""" + return self._cmp(other, operator.gt) + + def __ge__(self, other): + """self >= other""" + return self._cmp(other, operator.ge) + + def __abs__(self): + """abs(q)""" + return self._new(abs(self.numerator), self.denominator) + + def __pos__(self): + """+q""" + return self + + def __neg__(self): + """-q""" + return self._new(-self.numerator, self.denominator) + + def __add__(self, other): + """q1 + q2""" + if isinstance(other, PythonMPQ): + # + # This is much faster than the naive method used in the stdlib + # fractions module. Not sure where this method comes from + # though... + # + # Compare timings for something like: + # nums = range(1000) + # rats = [PythonMPQ(n, d) for n, d in zip(nums[:-5], nums[5:])] + # sum(rats) # <-- time this + # + ap, aq = self.numerator, self.denominator + bp, bq = other.numerator, other.denominator + g = gcd(aq, bq) + if g == 1: + p = ap*bq + aq*bp + q = bq*aq + else: + q1, q2 = aq//g, bq//g + p, q = ap*q2 + bp*q1, q1*q2 + g2 = gcd(p, g) + p, q = (p // g2), q * (g // g2) + + elif isinstance(other, int): + p = self.numerator + self.denominator * other + q = self.denominator + else: + return NotImplemented + + return self._new(p, q) + + def __radd__(self, other): + """z1 + q2""" + if isinstance(other, int): + p = self.numerator + self.denominator * other + q = self.denominator + return self._new(p, q) + else: + return NotImplemented + + def __sub__(self ,other): + """q1 - q2""" + if isinstance(other, PythonMPQ): + ap, aq = self.numerator, self.denominator + bp, bq = other.numerator, other.denominator + g = gcd(aq, bq) + if g == 1: + p = ap*bq - aq*bp + q = bq*aq + else: + q1, q2 = aq//g, bq//g + p, q = ap*q2 - bp*q1, q1*q2 + g2 = gcd(p, g) + p, q = (p // g2), q * (g // g2) + elif isinstance(other, int): + p = self.numerator - self.denominator*other + q = self.denominator + else: + return NotImplemented + + return self._new(p, q) + + def __rsub__(self, other): + """z1 - q2""" + if isinstance(other, int): + p = self.denominator * other - self.numerator + q = self.denominator + return self._new(p, q) + else: + return NotImplemented + + def __mul__(self, other): + """q1 * q2""" + if isinstance(other, PythonMPQ): + ap, aq = self.numerator, self.denominator + bp, bq = other.numerator, other.denominator + x1 = gcd(ap, bq) + x2 = gcd(bp, aq) + p, q = ((ap//x1)*(bp//x2), (aq//x2)*(bq//x1)) + elif isinstance(other, int): + x = gcd(other, self.denominator) + p = self.numerator*(other//x) + q = self.denominator//x + else: + return NotImplemented + + return self._new(p, q) + + def __rmul__(self, other): + """z1 * q2""" + if isinstance(other, int): + x = gcd(self.denominator, other) + p = self.numerator*(other//x) + q = self.denominator//x + return self._new(p, q) + else: + return NotImplemented + + def __pow__(self, exp): + """q ** z""" + p, q = self.numerator, self.denominator + + if exp < 0: + p, q, exp = q, p, -exp + + return self._new_check(p**exp, q**exp) + + def __truediv__(self, other): + """q1 / q2""" + if isinstance(other, PythonMPQ): + ap, aq = self.numerator, self.denominator + bp, bq = other.numerator, other.denominator + x1 = gcd(ap, bp) + x2 = gcd(bq, aq) + p, q = ((ap//x1)*(bq//x2), (aq//x2)*(bp//x1)) + elif isinstance(other, int): + x = gcd(other, self.numerator) + p = self.numerator//x + q = self.denominator*(other//x) + else: + return NotImplemented + + return self._new_check(p, q) + + def __rtruediv__(self, other): + """z / q""" + if isinstance(other, int): + x = gcd(self.numerator, other) + p = self.denominator*(other//x) + q = self.numerator//x + return self._new_check(p, q) + else: + return NotImplemented + + _compatible_types: tuple[Type, ...] = () + +# +# These are the types that PythonMPQ will interoperate with for operations +# and comparisons such as ==, + etc. We define this down here so that we can +# include PythonMPQ in the list as well. +# +PythonMPQ._compatible_types = (PythonMPQ, int, Decimal, Fraction) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_autowrap.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_autowrap.py new file mode 100644 index 0000000000000000000000000000000000000000..d469b552995b7625f786f3296089e41f42da75cb --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_autowrap.py @@ -0,0 +1,313 @@ +import sympy +import tempfile +import os +from pathlib import Path +from sympy.core.mod import Mod +from sympy.core.relational import Eq +from sympy.core.symbol import symbols +from sympy.external import import_module +from sympy.tensor import IndexedBase, Idx +from sympy.utilities.autowrap import autowrap, ufuncify, CodeWrapError +from sympy.testing.pytest import skip + +numpy = import_module('numpy', min_module_version='1.6.1') +Cython = import_module('Cython', min_module_version='0.15.1') +f2py = import_module('numpy.f2py', import_kwargs={'fromlist': ['f2py']}) + +f2pyworks = False +if f2py: + try: + autowrap(symbols('x'), 'f95', 'f2py') + except (CodeWrapError, ImportError, OSError): + f2pyworks = False + else: + f2pyworks = True + +a, b, c = symbols('a b c') +n, m, d = symbols('n m d', integer=True) +A, B, C = symbols('A B C', cls=IndexedBase) +i = Idx('i', m) +j = Idx('j', n) +k = Idx('k', d) + + +def has_module(module): + """ + Return True if module exists, otherwise run skip(). + + module should be a string. + """ + # To give a string of the module name to skip(), this function takes a + # string. So we don't waste time running import_module() more than once, + # just map the three modules tested here in this dict. + modnames = {'numpy': numpy, 'Cython': Cython, 'f2py': f2py} + + if modnames[module]: + if module == 'f2py' and not f2pyworks: + skip("Couldn't run f2py.") + return True + skip("Couldn't import %s." % module) + +# +# test runners used by several language-backend combinations +# + +def runtest_autowrap_twice(language, backend): + f = autowrap((((a + b)/c)**5).expand(), language, backend) + g = autowrap((((a + b)/c)**4).expand(), language, backend) + + # check that autowrap updates the module name. Else, g gives the same as f + assert f(1, -2, 1) == -1.0 + assert g(1, -2, 1) == 1.0 + + +def runtest_autowrap_trace(language, backend): + has_module('numpy') + trace = autowrap(A[i, i], language, backend) + assert trace(numpy.eye(100)) == 100 + + +def runtest_autowrap_matrix_vector(language, backend): + has_module('numpy') + x, y = symbols('x y', cls=IndexedBase) + expr = Eq(y[i], A[i, j]*x[j]) + mv = autowrap(expr, language, backend) + + # compare with numpy's dot product + M = numpy.random.rand(10, 20) + x = numpy.random.rand(20) + y = numpy.dot(M, x) + assert numpy.sum(numpy.abs(y - mv(M, x))) < 1e-13 + + +def runtest_autowrap_matrix_matrix(language, backend): + has_module('numpy') + expr = Eq(C[i, j], A[i, k]*B[k, j]) + matmat = autowrap(expr, language, backend) + + # compare with numpy's dot product + M1 = numpy.random.rand(10, 20) + M2 = numpy.random.rand(20, 15) + M3 = numpy.dot(M1, M2) + assert numpy.sum(numpy.abs(M3 - matmat(M1, M2))) < 1e-13 + + +def runtest_ufuncify(language, backend): + has_module('numpy') + a, b, c = symbols('a b c') + fabc = ufuncify([a, b, c], a*b + c, backend=backend) + facb = ufuncify([a, c, b], a*b + c, backend=backend) + grid = numpy.linspace(-2, 2, 50) + b = numpy.linspace(-5, 4, 50) + c = numpy.linspace(-1, 1, 50) + expected = grid*b + c + numpy.testing.assert_allclose(fabc(grid, b, c), expected) + numpy.testing.assert_allclose(facb(grid, c, b), expected) + + +def runtest_issue_10274(language, backend): + expr = (a - b + c)**(13) + tmp = tempfile.mkdtemp() + f = autowrap(expr, language, backend, tempdir=tmp, + helpers=('helper', a - b + c, (a, b, c))) + assert f(1, 1, 1) == 1 + + for file in os.listdir(tmp): + if not (file.startswith("wrapped_code_") and file.endswith(".c")): + continue + + with open(tmp + '/' + file) as fil: + lines = fil.readlines() + assert lines[0] == "/******************************************************************************\n" + assert "Code generated with SymPy " + sympy.__version__ in lines[1] + assert lines[2:] == [ + " * *\n", + " * See http://www.sympy.org/ for more information. *\n", + " * *\n", + " * This file is part of 'autowrap' *\n", + " ******************************************************************************/\n", + "#include " + '"' + file[:-1]+ 'h"' + "\n", + "#include \n", + "\n", + "double helper(double a, double b, double c) {\n", + "\n", + " double helper_result;\n", + " helper_result = a - b + c;\n", + " return helper_result;\n", + "\n", + "}\n", + "\n", + "double autofunc(double a, double b, double c) {\n", + "\n", + " double autofunc_result;\n", + " autofunc_result = pow(helper(a, b, c), 13);\n", + " return autofunc_result;\n", + "\n", + "}\n", + ] + + +def runtest_issue_15337(language, backend): + has_module('numpy') + # NOTE : autowrap was originally designed to only accept an iterable for + # the kwarg "helpers", but in issue 10274 the user mistakenly thought that + # if there was only a single helper it did not need to be passed via an + # iterable that wrapped the helper tuple. There were no tests for this + # behavior so when the code was changed to accept a single tuple it broke + # the original behavior. These tests below ensure that both now work. + a, b, c, d, e = symbols('a, b, c, d, e') + expr = (a - b + c - d + e)**13 + exp_res = (1. - 2. + 3. - 4. + 5.)**13 + + f = autowrap(expr, language, backend, args=(a, b, c, d, e), + helpers=('f1', a - b + c, (a, b, c))) + numpy.testing.assert_allclose(f(1, 2, 3, 4, 5), exp_res) + + f = autowrap(expr, language, backend, args=(a, b, c, d, e), + helpers=(('f1', a - b, (a, b)), ('f2', c - d, (c, d)))) + numpy.testing.assert_allclose(f(1, 2, 3, 4, 5), exp_res) + + +def test_issue_15230(): + has_module('f2py') + + x, y = symbols('x, y') + expr = Mod(x, 3.0) - Mod(y, -2.0) + f = autowrap(expr, args=[x, y], language='F95') + exp_res = float(expr.xreplace({x: 3.5, y: 2.7}).evalf()) + assert abs(f(3.5, 2.7) - exp_res) < 1e-14 + + x, y = symbols('x, y', integer=True) + expr = Mod(x, 3) - Mod(y, -2) + f = autowrap(expr, args=[x, y], language='F95') + assert f(3, 2) == expr.xreplace({x: 3, y: 2}) + +# +# tests of language-backend combinations +# + +# f2py + + +def test_wrap_twice_f95_f2py(): + has_module('f2py') + runtest_autowrap_twice('f95', 'f2py') + + +def test_autowrap_trace_f95_f2py(): + has_module('f2py') + runtest_autowrap_trace('f95', 'f2py') + + +def test_autowrap_matrix_vector_f95_f2py(): + has_module('f2py') + runtest_autowrap_matrix_vector('f95', 'f2py') + + +def test_autowrap_matrix_matrix_f95_f2py(): + has_module('f2py') + runtest_autowrap_matrix_matrix('f95', 'f2py') + + +def test_ufuncify_f95_f2py(): + has_module('f2py') + runtest_ufuncify('f95', 'f2py') + + +def test_issue_15337_f95_f2py(): + has_module('f2py') + runtest_issue_15337('f95', 'f2py') + +# Cython + + +def test_wrap_twice_c_cython(): + has_module('Cython') + runtest_autowrap_twice('C', 'cython') + + +def test_autowrap_trace_C_Cython(): + has_module('Cython') + runtest_autowrap_trace('C99', 'cython') + + +def test_autowrap_matrix_vector_C_cython(): + has_module('Cython') + runtest_autowrap_matrix_vector('C99', 'cython') + + +def test_autowrap_matrix_matrix_C_cython(): + has_module('Cython') + runtest_autowrap_matrix_matrix('C99', 'cython') + + +def test_ufuncify_C_Cython(): + has_module('Cython') + runtest_ufuncify('C99', 'cython') + + +def test_issue_10274_C_cython(): + has_module('Cython') + runtest_issue_10274('C89', 'cython') + + +def test_issue_15337_C_cython(): + has_module('Cython') + runtest_issue_15337('C89', 'cython') + + +def test_autowrap_custom_printer(): + has_module('Cython') + + from sympy.core.numbers import pi + from sympy.utilities.codegen import C99CodeGen + from sympy.printing.c import C99CodePrinter + + class PiPrinter(C99CodePrinter): + def _print_Pi(self, expr): + return "S_PI" + + printer = PiPrinter() + gen = C99CodeGen(printer=printer) + gen.preprocessor_statements.append('#include "shortpi.h"') + + expr = pi * a + + expected = ( + '#include "%s"\n' + '#include \n' + '#include "shortpi.h"\n' + '\n' + 'double autofunc(double a) {\n' + '\n' + ' double autofunc_result;\n' + ' autofunc_result = S_PI*a;\n' + ' return autofunc_result;\n' + '\n' + '}\n' + ) + + tmpdir = tempfile.mkdtemp() + # write a trivial header file to use in the generated code + Path(os.path.join(tmpdir, 'shortpi.h')).write_text('#define S_PI 3.14') + + func = autowrap(expr, backend='cython', tempdir=tmpdir, code_gen=gen) + + assert func(4.2) == 3.14 * 4.2 + + # check that the generated code is correct + for filename in os.listdir(tmpdir): + if filename.startswith('wrapped_code') and filename.endswith('.c'): + with open(os.path.join(tmpdir, filename)) as f: + lines = f.readlines() + expected = expected % filename.replace('.c', '.h') + assert ''.join(lines[7:]) == expected + + +# Numpy + +def test_ufuncify_numpy(): + # This test doesn't use Cython, but if Cython works, then there is a valid + # C compiler, which is needed. + has_module('Cython') + runtest_ufuncify('C99', 'numpy') diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_codegen.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_codegen.py new file mode 100644 index 0000000000000000000000000000000000000000..8a4fe28300b86fb0b38d98fcf2fcbbe514cf720f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_codegen.py @@ -0,0 +1,375 @@ +# This tests the compilation and execution of the source code generated with +# utilities.codegen. The compilation takes place in a temporary directory that +# is removed after the test. By default the test directory is always removed, +# but this behavior can be changed by setting the environment variable +# SYMPY_TEST_CLEAN_TEMP to: +# export SYMPY_TEST_CLEAN_TEMP=always : the default behavior. +# export SYMPY_TEST_CLEAN_TEMP=success : only remove the directories of working tests. +# export SYMPY_TEST_CLEAN_TEMP=never : never remove the directories with the test code. +# When a directory is not removed, the necessary information is printed on +# screen to find the files that belong to the (failed) tests. If a test does +# not fail, py.test captures all the output and you will not see the directories +# corresponding to the successful tests. Use the --nocapture option to see all +# the output. + +# All tests below have a counterpart in utilities/test/test_codegen.py. In the +# latter file, the resulting code is compared with predefined strings, without +# compilation or execution. + +# All the generated Fortran code should conform with the Fortran 95 standard, +# and all the generated C code should be ANSI C, which facilitates the +# incorporation in various projects. The tests below assume that the binary cc +# is somewhere in the path and that it can compile ANSI C code. + +from sympy.abc import x, y, z +from sympy.testing.pytest import IS_WASM, skip +from sympy.utilities.codegen import codegen, make_routine, get_code_generator +import sys +import os +import tempfile +import subprocess +from pathlib import Path + + +# templates for the main program that will test the generated code. + +main_template = {} +main_template['F95'] = """ +program main + include "codegen.h" + integer :: result; + result = 0 + + %(statements)s + + call exit(result) +end program +""" + +main_template['C89'] = """ +#include "codegen.h" +#include +#include + +int main() { + int result = 0; + + %(statements)s + + return result; +} +""" +main_template['C99'] = main_template['C89'] +# templates for the numerical tests + +numerical_test_template = {} +numerical_test_template['C89'] = """ + if (fabs(%(call)s)>%(threshold)s) { + printf("Numerical validation failed: %(call)s=%%e threshold=%(threshold)s\\n", %(call)s); + result = -1; + } +""" +numerical_test_template['C99'] = numerical_test_template['C89'] + +numerical_test_template['F95'] = """ + if (abs(%(call)s)>%(threshold)s) then + write(6,"('Numerical validation failed:')") + write(6,"('%(call)s=',e15.5,'threshold=',e15.5)") %(call)s, %(threshold)s + result = -1; + end if +""" +# command sequences for supported compilers + +compile_commands = {} +compile_commands['cc'] = [ + "cc -c codegen.c -o codegen.o", + "cc -c main.c -o main.o", + "cc main.o codegen.o -lm -o test.exe" +] + +compile_commands['gfortran'] = [ + "gfortran -c codegen.f90 -o codegen.o", + "gfortran -ffree-line-length-none -c main.f90 -o main.o", + "gfortran main.o codegen.o -o test.exe" +] + +compile_commands['g95'] = [ + "g95 -c codegen.f90 -o codegen.o", + "g95 -ffree-line-length-huge -c main.f90 -o main.o", + "g95 main.o codegen.o -o test.exe" +] + +compile_commands['ifort'] = [ + "ifort -c codegen.f90 -o codegen.o", + "ifort -c main.f90 -o main.o", + "ifort main.o codegen.o -o test.exe" +] + +combinations_lang_compiler = [ + ('C89', 'cc'), + ('C99', 'cc'), + ('F95', 'ifort'), + ('F95', 'gfortran'), + ('F95', 'g95') +] + +def try_run(commands): + """Run a series of commands and only return True if all ran fine.""" + if IS_WASM: + return False + with open(os.devnull, 'w') as null: + for command in commands: + retcode = subprocess.call(command, stdout=null, shell=True, + stderr=subprocess.STDOUT) + if retcode != 0: + return False + return True + + +def run_test(label, routines, numerical_tests, language, commands, friendly=True): + """A driver for the codegen tests. + + This driver assumes that a compiler ifort is present in the PATH and that + ifort is (at least) a Fortran 90 compiler. The generated code is written in + a temporary directory, together with a main program that validates the + generated code. The test passes when the compilation and the validation + run correctly. + """ + + # Check input arguments before touching the file system + language = language.upper() + assert language in main_template + assert language in numerical_test_template + + # Check that environment variable makes sense + clean = os.getenv('SYMPY_TEST_CLEAN_TEMP', 'always').lower() + if clean not in ('always', 'success', 'never'): + raise ValueError("SYMPY_TEST_CLEAN_TEMP must be one of the following: 'always', 'success' or 'never'.") + + # Do all the magic to compile, run and validate the test code + # 1) prepare the temporary working directory, switch to that dir + work = tempfile.mkdtemp("_sympy_%s_test" % language, "%s_" % label) + oldwork = os.getcwd() + os.chdir(work) + + # 2) write the generated code + if friendly: + # interpret the routines as a name_expr list and call the friendly + # function codegen + codegen(routines, language, "codegen", to_files=True) + else: + code_gen = get_code_generator(language, "codegen") + code_gen.write(routines, "codegen", to_files=True) + + # 3) write a simple main program that links to the generated code, and that + # includes the numerical tests + test_strings = [] + for fn_name, args, expected, threshold in numerical_tests: + call_string = "%s(%s)-(%s)" % ( + fn_name, ",".join(str(arg) for arg in args), expected) + if language == "F95": + call_string = fortranize_double_constants(call_string) + threshold = fortranize_double_constants(str(threshold)) + test_strings.append(numerical_test_template[language] % { + "call": call_string, + "threshold": threshold, + }) + + if language == "F95": + f_name = "main.f90" + elif language.startswith("C"): + f_name = "main.c" + else: + raise NotImplementedError( + "FIXME: filename extension unknown for language: %s" % language) + + Path(f_name).write_text( + main_template[language] % {'statements': "".join(test_strings)}) + + # 4) Compile and link + compiled = try_run(commands) + + # 5) Run if compiled + if compiled: + executed = try_run(["./test.exe"]) + else: + executed = False + + # 6) Clean up stuff + if clean == 'always' or (clean == 'success' and compiled and executed): + def safe_remove(filename): + if os.path.isfile(filename): + os.remove(filename) + safe_remove("codegen.f90") + safe_remove("codegen.c") + safe_remove("codegen.h") + safe_remove("codegen.o") + safe_remove("main.f90") + safe_remove("main.c") + safe_remove("main.o") + safe_remove("test.exe") + os.chdir(oldwork) + os.rmdir(work) + else: + print("TEST NOT REMOVED: %s" % work, file=sys.stderr) + os.chdir(oldwork) + + # 7) Do the assertions in the end + assert compiled, "failed to compile %s code with:\n%s" % ( + language, "\n".join(commands)) + assert executed, "failed to execute %s code from:\n%s" % ( + language, "\n".join(commands)) + + +def fortranize_double_constants(code_string): + """ + Replaces every literal float with literal doubles + """ + import re + pattern_exp = re.compile(r'\d+(\.)?\d*[eE]-?\d+') + pattern_float = re.compile(r'\d+\.\d*(?!\d*d)') + + def subs_exp(matchobj): + return re.sub('[eE]', 'd', matchobj.group(0)) + + def subs_float(matchobj): + return "%sd0" % matchobj.group(0) + + code_string = pattern_exp.sub(subs_exp, code_string) + code_string = pattern_float.sub(subs_float, code_string) + + return code_string + + +def is_feasible(language, commands): + # This test should always work, otherwise the compiler is not present. + routine = make_routine("test", x) + numerical_tests = [ + ("test", ( 1.0,), 1.0, 1e-15), + ("test", (-1.0,), -1.0, 1e-15), + ] + try: + run_test("is_feasible", [routine], numerical_tests, language, commands, + friendly=False) + return True + except AssertionError: + return False + +valid_lang_commands = [] +invalid_lang_compilers = [] +for lang, compiler in combinations_lang_compiler: + commands = compile_commands[compiler] + if is_feasible(lang, commands): + valid_lang_commands.append((lang, commands)) + else: + invalid_lang_compilers.append((lang, compiler)) + +# We test all language-compiler combinations, just to report what is skipped + +def test_C89_cc(): + if ("C89", 'cc') in invalid_lang_compilers: + skip("`cc' command didn't work as expected (C89)") + + +def test_C99_cc(): + if ("C99", 'cc') in invalid_lang_compilers: + skip("`cc' command didn't work as expected (C99)") + + +def test_F95_ifort(): + if ("F95", 'ifort') in invalid_lang_compilers: + skip("`ifort' command didn't work as expected") + + +def test_F95_gfortran(): + if ("F95", 'gfortran') in invalid_lang_compilers: + skip("`gfortran' command didn't work as expected") + + +def test_F95_g95(): + if ("F95", 'g95') in invalid_lang_compilers: + skip("`g95' command didn't work as expected") + +# Here comes the actual tests + + +def test_basic_codegen(): + numerical_tests = [ + ("test", (1.0, 6.0, 3.0), 21.0, 1e-15), + ("test", (-1.0, 2.0, -2.5), -2.5, 1e-15), + ] + name_expr = [("test", (x + y)*z)] + for lang, commands in valid_lang_commands: + run_test("basic_codegen", name_expr, numerical_tests, lang, commands) + + +def test_intrinsic_math1_codegen(): + # not included: log10 + from sympy.core.evalf import N + from sympy.functions import ln + from sympy.functions.elementary.exponential import log + from sympy.functions.elementary.hyperbolic import (cosh, sinh, tanh) + from sympy.functions.elementary.integers import (ceiling, floor) + from sympy.functions.elementary.miscellaneous import sqrt + from sympy.functions.elementary.trigonometric import (acos, asin, atan, cos, sin, tan) + name_expr = [ + ("test_fabs", abs(x)), + ("test_acos", acos(x)), + ("test_asin", asin(x)), + ("test_atan", atan(x)), + ("test_cos", cos(x)), + ("test_cosh", cosh(x)), + ("test_log", log(x)), + ("test_ln", ln(x)), + ("test_sin", sin(x)), + ("test_sinh", sinh(x)), + ("test_sqrt", sqrt(x)), + ("test_tan", tan(x)), + ("test_tanh", tanh(x)), + ] + numerical_tests = [] + for name, expr in name_expr: + for xval in 0.2, 0.5, 0.8: + expected = N(expr.subs(x, xval)) + numerical_tests.append((name, (xval,), expected, 1e-14)) + for lang, commands in valid_lang_commands: + if lang.startswith("C"): + name_expr_C = [("test_floor", floor(x)), ("test_ceil", ceiling(x))] + else: + name_expr_C = [] + run_test("intrinsic_math1", name_expr + name_expr_C, + numerical_tests, lang, commands) + + +def test_instrinsic_math2_codegen(): + # not included: frexp, ldexp, modf, fmod + from sympy.core.evalf import N + from sympy.functions.elementary.trigonometric import atan2 + name_expr = [ + ("test_atan2", atan2(x, y)), + ("test_pow", x**y), + ] + numerical_tests = [] + for name, expr in name_expr: + for xval, yval in (0.2, 1.3), (0.5, -0.2), (0.8, 0.8): + expected = N(expr.subs(x, xval).subs(y, yval)) + numerical_tests.append((name, (xval, yval), expected, 1e-14)) + for lang, commands in valid_lang_commands: + run_test("intrinsic_math2", name_expr, numerical_tests, lang, commands) + + +def test_complicated_codegen(): + from sympy.core.evalf import N + from sympy.functions.elementary.trigonometric import (cos, sin, tan) + name_expr = [ + ("test1", ((sin(x) + cos(y) + tan(z))**7).expand()), + ("test2", cos(cos(cos(cos(cos(cos(cos(cos(x + y + z))))))))), + ] + numerical_tests = [] + for name, expr in name_expr: + for xval, yval, zval in (0.2, 1.3, -0.3), (0.5, -0.2, 0.0), (0.8, 2.1, 0.8): + expected = N(expr.subs(x, xval).subs(y, yval).subs(z, zval)) + numerical_tests.append((name, (xval, yval, zval), expected, 1e-12)) + for lang, commands in valid_lang_commands: + run_test( + "complicated_codegen", name_expr, numerical_tests, lang, commands) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_gmpy.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_gmpy.py new file mode 100644 index 0000000000000000000000000000000000000000..d88f9da0c6c26c15f529ce485fff5b72342170ea --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_gmpy.py @@ -0,0 +1,12 @@ +from sympy.external.gmpy import LONG_MAX, iroot +from sympy.testing.pytest import raises + + +def test_iroot(): + assert iroot(2, LONG_MAX) == (1, False) + assert iroot(2, LONG_MAX + 1) == (1, False) + for x in range(3): + assert iroot(x, 1) == (x, True) + raises(ValueError, lambda: iroot(-1, 1)) + raises(ValueError, lambda: iroot(0, 0)) + raises(ValueError, lambda: iroot(0, -1)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_importtools.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_importtools.py new file mode 100644 index 0000000000000000000000000000000000000000..0b954070c179282ed2bcf5735d802c5f22a3a261 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_importtools.py @@ -0,0 +1,40 @@ +from sympy.external import import_module +from sympy.testing.pytest import warns + +# fixes issue that arose in addressing issue 6533 +def test_no_stdlib_collections(): + ''' + make sure we get the right collections when it is not part of a + larger list + ''' + import collections + matplotlib = import_module('matplotlib', + import_kwargs={'fromlist': ['cm', 'collections']}, + min_module_version='1.1.0', catch=(RuntimeError,)) + if matplotlib: + assert collections != matplotlib.collections + +def test_no_stdlib_collections2(): + ''' + make sure we get the right collections when it is not part of a + larger list + ''' + import collections + matplotlib = import_module('matplotlib', + import_kwargs={'fromlist': ['collections']}, + min_module_version='1.1.0', catch=(RuntimeError,)) + if matplotlib: + assert collections != matplotlib.collections + +def test_no_stdlib_collections3(): + '''make sure we get the right collections with no catch''' + import collections + matplotlib = import_module('matplotlib', + import_kwargs={'fromlist': ['cm', 'collections']}, + min_module_version='1.1.0') + if matplotlib: + assert collections != matplotlib.collections + +def test_min_module_version_python3_basestring_error(): + with warns(UserWarning): + import_module('mpmath', min_module_version='1000.0.1') diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_ntheory.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_ntheory.py new file mode 100644 index 0000000000000000000000000000000000000000..00824481ad27aa9071ea5801fb3bde75cacbc3c8 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_ntheory.py @@ -0,0 +1,307 @@ +from itertools import permutations + +from sympy.external.ntheory import (bit_scan1, remove, bit_scan0, is_fermat_prp, + is_euler_prp, is_strong_prp, gcdext, _lucas_sequence, + is_fibonacci_prp, is_lucas_prp, is_selfridge_prp, + is_strong_lucas_prp, is_strong_selfridge_prp, + is_bpsw_prp, is_strong_bpsw_prp) +from sympy.testing.pytest import raises + + +def test_bit_scan1(): + assert bit_scan1(0) is None + assert bit_scan1(1) == 0 + assert bit_scan1(-1) == 0 + assert bit_scan1(2) == 1 + assert bit_scan1(7) == 0 + assert bit_scan1(-7) == 0 + for i in range(100): + assert bit_scan1(1 << i) == i + assert bit_scan1((1 << i) * 31337) == i + for i in range(500): + n = (1 << 500) + (1 << i) + assert bit_scan1(n) == i + assert bit_scan1(1 << 1000001) == 1000001 + assert bit_scan1((1 << 273956)*7**37) == 273956 + # issue 12709 + for i in range(1, 10): + big = 1 << i + assert bit_scan1(-big) == bit_scan1(big) + + +def test_bit_scan0(): + assert bit_scan0(-1) is None + assert bit_scan0(0) == 0 + assert bit_scan0(1) == 1 + assert bit_scan0(-2) == 0 + + +def test_remove(): + raises(ValueError, lambda: remove(1, 1)) + assert remove(0, 3) == (0, 0) + for f in range(2, 10): + for y in range(2, 1000): + for z in [1, 17, 101, 1009]: + assert remove(z*f**y, f) == (z, y) + + +def test_gcdext(): + assert gcdext(0, 0) == (0, 0, 0) + assert gcdext(3, 0) == (3, 1, 0) + assert gcdext(0, 4) == (4, 0, 1) + + for n in range(1, 10): + assert gcdext(n, 1) == gcdext(-n, 1) == (1, 0, 1) + assert gcdext(n, -1) == gcdext(-n, -1) == (1, 0, -1) + assert gcdext(n, n) == gcdext(-n, n) == (n, 0, 1) + assert gcdext(n, -n) == gcdext(-n, -n) == (n, 0, -1) + + for n in range(2, 10): + assert gcdext(1, n) == gcdext(1, -n) == (1, 1, 0) + assert gcdext(-1, n) == gcdext(-1, -n) == (1, -1, 0) + + for a, b in permutations([2**5, 3, 5, 7**2, 11], 2): + g, x, y = gcdext(a, b) + assert g == a*x + b*y == 1 + + +def test_is_fermat_prp(): + # invalid input + raises(ValueError, lambda: is_fermat_prp(0, 10)) + raises(ValueError, lambda: is_fermat_prp(5, 1)) + + # n = 1 + assert not is_fermat_prp(1, 3) + + # n is prime + assert is_fermat_prp(2, 4) + assert is_fermat_prp(3, 2) + assert is_fermat_prp(11, 3) + assert is_fermat_prp(2**31-1, 5) + + # A001567 + pseudorpime = [341, 561, 645, 1105, 1387, 1729, 1905, 2047, + 2465, 2701, 2821, 3277, 4033, 4369, 4371, 4681] + for n in pseudorpime: + assert is_fermat_prp(n, 2) + + # A020136 + pseudorpime = [15, 85, 91, 341, 435, 451, 561, 645, 703, 1105, + 1247, 1271, 1387, 1581, 1695, 1729, 1891, 1905] + for n in pseudorpime: + assert is_fermat_prp(n, 4) + + +def test_is_euler_prp(): + # invalid input + raises(ValueError, lambda: is_euler_prp(0, 10)) + raises(ValueError, lambda: is_euler_prp(5, 1)) + + # n = 1 + assert not is_euler_prp(1, 3) + + # n is prime + assert is_euler_prp(2, 4) + assert is_euler_prp(3, 2) + assert is_euler_prp(11, 3) + assert is_euler_prp(2**31-1, 5) + + # A047713 + pseudorpime = [561, 1105, 1729, 1905, 2047, 2465, 3277, 4033, + 4681, 6601, 8321, 8481, 10585, 12801, 15841] + for n in pseudorpime: + assert is_euler_prp(n, 2) + + # A048950 + pseudorpime = [121, 703, 1729, 1891, 2821, 3281, 7381, 8401, + 8911, 10585, 12403, 15457, 15841, 16531, 18721] + for n in pseudorpime: + assert is_euler_prp(n, 3) + + +def test_is_strong_prp(): + # invalid input + raises(ValueError, lambda: is_strong_prp(0, 10)) + raises(ValueError, lambda: is_strong_prp(5, 1)) + + # n = 1 + assert not is_strong_prp(1, 3) + + # n is prime + assert is_strong_prp(2, 4) + assert is_strong_prp(3, 2) + assert is_strong_prp(11, 3) + assert is_strong_prp(2**31-1, 5) + + # A001262 + pseudorpime = [2047, 3277, 4033, 4681, 8321, 15841, 29341, + 42799, 49141, 52633, 65281, 74665, 80581] + for n in pseudorpime: + assert is_strong_prp(n, 2) + + # A020229 + pseudorpime = [121, 703, 1891, 3281, 8401, 8911, 10585, 12403, + 16531, 18721, 19345, 23521, 31621, 44287, 47197] + for n in pseudorpime: + assert is_strong_prp(n, 3) + + +def test_lucas_sequence(): + def lucas_u(P, Q, length): + array = [0] * length + array[1] = 1 + for k in range(2, length): + array[k] = P * array[k - 1] - Q * array[k - 2] + return array + + def lucas_v(P, Q, length): + array = [0] * length + array[0] = 2 + array[1] = P + for k in range(2, length): + array[k] = P * array[k - 1] - Q * array[k - 2] + return array + + length = 20 + for P in range(-10, 10): + for Q in range(-10, 10): + D = P**2 - 4*Q + if D == 0: + continue + us = lucas_u(P, Q, length) + vs = lucas_v(P, Q, length) + for n in range(3, 100, 2): + for k in range(length): + U, V, Qk = _lucas_sequence(n, P, Q, k) + assert U == us[k] % n + assert V == vs[k] % n + assert pow(Q, k, n) == Qk + + +def test_is_fibonacci_prp(): + # invalid input + raises(ValueError, lambda: is_fibonacci_prp(3, 2, 1)) + raises(ValueError, lambda: is_fibonacci_prp(3, -5, 1)) + raises(ValueError, lambda: is_fibonacci_prp(3, 5, 2)) + raises(ValueError, lambda: is_fibonacci_prp(0, 5, -1)) + + # n = 1 + assert not is_fibonacci_prp(1, 3, 1) + + # n is prime + assert is_fibonacci_prp(2, 5, 1) + assert is_fibonacci_prp(3, 6, -1) + assert is_fibonacci_prp(11, 7, 1) + assert is_fibonacci_prp(2**31-1, 8, -1) + + # A005845 + pseudorpime = [705, 2465, 2737, 3745, 4181, 5777, 6721, + 10877, 13201, 15251, 24465, 29281, 34561] + for n in pseudorpime: + assert is_fibonacci_prp(n, 1, -1) + + +def test_is_lucas_prp(): + # invalid input + raises(ValueError, lambda: is_lucas_prp(3, 2, 1)) + raises(ValueError, lambda: is_lucas_prp(0, 5, -1)) + raises(ValueError, lambda: is_lucas_prp(15, 3, 1)) + + # n = 1 + assert not is_lucas_prp(1, 3, 1) + + # n is prime + assert is_lucas_prp(2, 5, 2) + assert is_lucas_prp(3, 6, -1) + assert is_lucas_prp(11, 7, 5) + assert is_lucas_prp(2**31-1, 8, -3) + + # A081264 + pseudorpime = [323, 377, 1891, 3827, 4181, 5777, 6601, 6721, + 8149, 10877, 11663, 13201, 13981, 15251, 17119] + for n in pseudorpime: + assert is_lucas_prp(n, 1, -1) + + +def test_is_selfridge_prp(): + # invalid input + raises(ValueError, lambda: is_selfridge_prp(0)) + + # n = 1 + assert not is_selfridge_prp(1) + + # n is prime + assert is_selfridge_prp(2) + assert is_selfridge_prp(3) + assert is_selfridge_prp(11) + assert is_selfridge_prp(2**31-1) + + # A217120 + pseudorpime = [323, 377, 1159, 1829, 3827, 5459, 5777, 9071, + 9179, 10877, 11419, 11663, 13919, 14839, 16109] + for n in pseudorpime: + assert is_selfridge_prp(n) + + +def test_is_strong_lucas_prp(): + # invalid input + raises(ValueError, lambda: is_strong_lucas_prp(3, 2, 1)) + raises(ValueError, lambda: is_strong_lucas_prp(0, 5, -1)) + raises(ValueError, lambda: is_strong_lucas_prp(15, 3, 1)) + + # n = 1 + assert not is_strong_lucas_prp(1, 3, 1) + + # n is prime + assert is_strong_lucas_prp(2, 5, 2) + assert is_strong_lucas_prp(3, 6, -1) + assert is_strong_lucas_prp(11, 7, 5) + assert is_strong_lucas_prp(2**31-1, 8, -3) + + +def test_is_strong_selfridge_prp(): + # invalid input + raises(ValueError, lambda: is_strong_selfridge_prp(0)) + + # n = 1 + assert not is_strong_selfridge_prp(1) + + # n is prime + assert is_strong_selfridge_prp(2) + assert is_strong_selfridge_prp(3) + assert is_strong_selfridge_prp(11) + assert is_strong_selfridge_prp(2**31-1) + + # A217255 + pseudorpime = [5459, 5777, 10877, 16109, 18971, 22499, 24569, + 25199, 40309, 58519, 75077, 97439, 100127, 113573] + for n in pseudorpime: + assert is_strong_selfridge_prp(n) + + +def test_is_bpsw_prp(): + # invalid input + raises(ValueError, lambda: is_bpsw_prp(0)) + + # n = 1 + assert not is_bpsw_prp(1) + + # n is prime + assert is_bpsw_prp(2) + assert is_bpsw_prp(3) + assert is_bpsw_prp(11) + assert is_bpsw_prp(2**31-1) + + +def test_is_strong_bpsw_prp(): + # invalid input + raises(ValueError, lambda: is_strong_bpsw_prp(0)) + + # n = 1 + assert not is_strong_bpsw_prp(1) + + # n is prime + assert is_strong_bpsw_prp(2) + assert is_strong_bpsw_prp(3) + assert is_strong_bpsw_prp(11) + assert is_strong_bpsw_prp(2**31-1) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_numpy.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_numpy.py new file mode 100644 index 0000000000000000000000000000000000000000..cd456d0d6cc49138c29d7ab28ee02694448d578f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_numpy.py @@ -0,0 +1,335 @@ +# This testfile tests SymPy <-> NumPy compatibility + +# Don't test any SymPy features here. Just pure interaction with NumPy. +# Always write regular SymPy tests for anything, that can be tested in pure +# Python (without numpy). Here we test everything, that a user may need when +# using SymPy with NumPy +from sympy.external.importtools import version_tuple +from sympy.external import import_module + +numpy = import_module('numpy') +if numpy: + array, matrix, ndarray = numpy.array, numpy.matrix, numpy.ndarray +else: + #bin/test will not execute any tests now + disabled = True + + +from sympy.core.numbers import (Float, Integer, Rational) +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.trigonometric import sin +from sympy.matrices.dense import (Matrix, list2numpy, matrix2numpy, symarray) +from sympy.utilities.lambdify import lambdify +import sympy + +import mpmath +from sympy.abc import x, y, z +from sympy.utilities.decorator import conserve_mpmath_dps +from sympy.utilities.exceptions import ignore_warnings +from sympy.testing.pytest import raises + + +# first, systematically check, that all operations are implemented and don't +# raise an exception + + +def test_systematic_basic(): + def s(sympy_object, numpy_array): + _ = [sympy_object + numpy_array, + numpy_array + sympy_object, + sympy_object - numpy_array, + numpy_array - sympy_object, + sympy_object * numpy_array, + numpy_array * sympy_object, + sympy_object / numpy_array, + numpy_array / sympy_object, + sympy_object ** numpy_array, + numpy_array ** sympy_object] + x = Symbol("x") + y = Symbol("y") + sympy_objs = [ + Rational(2, 3), + Float("1.3"), + x, + y, + pow(x, y)*y, + Integer(5), + Float(5.5), + ] + numpy_objs = [ + array([1]), + array([3, 8, -1]), + array([x, x**2, Rational(5)]), + array([x/y*sin(y), 5, Rational(5)]), + ] + for x in sympy_objs: + for y in numpy_objs: + s(x, y) + + +# now some random tests, that test particular problems and that also +# check that the results of the operations are correct + +def test_basics(): + one = Rational(1) + zero = Rational(0) + assert array(1) == array(one) + assert array([one]) == array([one]) + assert array([x]) == array([x]) + assert array(x) == array(Symbol("x")) + assert array(one + x) == array(1 + x) + + X = array([one, zero, zero]) + assert (X == array([one, zero, zero])).all() + assert (X == array([one, 0, 0])).all() + + +def test_arrays(): + one = Rational(1) + zero = Rational(0) + X = array([one, zero, zero]) + Y = one*X + X = array([Symbol("a") + Rational(1, 2)]) + Y = X + X + assert Y == array([1 + 2*Symbol("a")]) + Y = Y + 1 + assert Y == array([2 + 2*Symbol("a")]) + Y = X - X + assert Y == array([0]) + + +def test_conversion1(): + a = list2numpy([x**2, x]) + #looks like an array? + assert isinstance(a, ndarray) + assert a[0] == x**2 + assert a[1] == x + assert len(a) == 2 + #yes, it's the array + + +def test_conversion2(): + a = 2*list2numpy([x**2, x]) + b = list2numpy([2*x**2, 2*x]) + assert (a == b).all() + + one = Rational(1) + zero = Rational(0) + X = list2numpy([one, zero, zero]) + Y = one*X + X = list2numpy([Symbol("a") + Rational(1, 2)]) + Y = X + X + assert Y == array([1 + 2*Symbol("a")]) + Y = Y + 1 + assert Y == array([2 + 2*Symbol("a")]) + Y = X - X + assert Y == array([0]) + + +def test_list2numpy(): + assert (array([x**2, x]) == list2numpy([x**2, x])).all() + + +def test_Matrix1(): + m = Matrix([[x, x**2], [5, 2/x]]) + assert (array(m.subs(x, 2)) == array([[2, 4], [5, 1]])).all() + m = Matrix([[sin(x), x**2], [5, 2/x]]) + assert (array(m.subs(x, 2)) == array([[sin(2), 4], [5, 1]])).all() + + +def test_Matrix2(): + m = Matrix([[x, x**2], [5, 2/x]]) + with ignore_warnings(PendingDeprecationWarning): + assert (matrix(m.subs(x, 2)) == matrix([[2, 4], [5, 1]])).all() + m = Matrix([[sin(x), x**2], [5, 2/x]]) + with ignore_warnings(PendingDeprecationWarning): + assert (matrix(m.subs(x, 2)) == matrix([[sin(2), 4], [5, 1]])).all() + + +def test_Matrix3(): + a = array([[2, 4], [5, 1]]) + assert Matrix(a) == Matrix([[2, 4], [5, 1]]) + assert Matrix(a) != Matrix([[2, 4], [5, 2]]) + a = array([[sin(2), 4], [5, 1]]) + assert Matrix(a) == Matrix([[sin(2), 4], [5, 1]]) + assert Matrix(a) != Matrix([[sin(0), 4], [5, 1]]) + + +def test_Matrix4(): + with ignore_warnings(PendingDeprecationWarning): + a = matrix([[2, 4], [5, 1]]) + assert Matrix(a) == Matrix([[2, 4], [5, 1]]) + assert Matrix(a) != Matrix([[2, 4], [5, 2]]) + with ignore_warnings(PendingDeprecationWarning): + a = matrix([[sin(2), 4], [5, 1]]) + assert Matrix(a) == Matrix([[sin(2), 4], [5, 1]]) + assert Matrix(a) != Matrix([[sin(0), 4], [5, 1]]) + + +def test_Matrix_sum(): + M = Matrix([[1, 2, 3], [x, y, x], [2*y, -50, z*x]]) + with ignore_warnings(PendingDeprecationWarning): + m = matrix([[2, 3, 4], [x, 5, 6], [x, y, z**2]]) + assert M + m == Matrix([[3, 5, 7], [2*x, y + 5, x + 6], [2*y + x, y - 50, z*x + z**2]]) + assert m + M == Matrix([[3, 5, 7], [2*x, y + 5, x + 6], [2*y + x, y - 50, z*x + z**2]]) + assert M + m == M.add(m) + + +def test_Matrix_mul(): + M = Matrix([[1, 2, 3], [x, y, x]]) + with ignore_warnings(PendingDeprecationWarning): + m = matrix([[2, 4], [x, 6], [x, z**2]]) + assert M*m == Matrix([ + [ 2 + 5*x, 16 + 3*z**2], + [2*x + x*y + x**2, 4*x + 6*y + x*z**2], + ]) + + assert m*M == Matrix([ + [ 2 + 4*x, 4 + 4*y, 6 + 4*x], + [ 7*x, 2*x + 6*y, 9*x], + [x + x*z**2, 2*x + y*z**2, 3*x + x*z**2], + ]) + a = array([2]) + assert a[0] * M == 2 * M + assert M * a[0] == 2 * M + + +def test_Matrix_array(): + class matarray: + def __array__(self, dtype=object, copy=None): + if copy is not None and not copy: + raise TypeError("Cannot implement copy=False when converting Matrix to ndarray") + from numpy import array + return array([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) + matarr = matarray() + assert Matrix(matarr) == Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) + + +def test_matrix2numpy(): + a = matrix2numpy(Matrix([[1, x**2], [3*sin(x), 0]])) + assert isinstance(a, ndarray) + assert a.shape == (2, 2) + assert a[0, 0] == 1 + assert a[0, 1] == x**2 + assert a[1, 0] == 3*sin(x) + assert a[1, 1] == 0 + + +def test_matrix2numpy_conversion(): + a = Matrix([[1, 2, sin(x)], [x**2, x, Rational(1, 2)]]) + b = array([[1, 2, sin(x)], [x**2, x, Rational(1, 2)]]) + assert (matrix2numpy(a) == b).all() + assert matrix2numpy(a).dtype == numpy.dtype('object') + + c = matrix2numpy(Matrix([[1, 2], [10, 20]]), dtype='int8') + d = matrix2numpy(Matrix([[1, 2], [10, 20]]), dtype='float64') + assert c.dtype == numpy.dtype('int8') + assert d.dtype == numpy.dtype('float64') + + +def test_issue_3728(): + assert (Rational(1, 2)*array([2*x, 0]) == array([x, 0])).all() + assert (Rational(1, 2) + array( + [2*x, 0]) == array([2*x + Rational(1, 2), Rational(1, 2)])).all() + assert (Float("0.5")*array([2*x, 0]) == array([Float("1.0")*x, 0])).all() + assert (Float("0.5") + array( + [2*x, 0]) == array([2*x + Float("0.5"), Float("0.5")])).all() + + +@conserve_mpmath_dps +def test_lambdify(): + mpmath.mp.dps = 16 + sin02 = mpmath.mpf("0.198669330795061215459412627") + f = lambdify(x, sin(x), "numpy") + prec = 1e-15 + assert -prec < f(0.2) - sin02 < prec + + # if this succeeds, it can't be a numpy function + + if version_tuple(numpy.__version__) >= version_tuple('1.17'): + with raises(TypeError): + f(x) + else: + with raises(AttributeError): + f(x) + + +def test_lambdify_matrix(): + f = lambdify(x, Matrix([[x, 2*x], [1, 2]]), [{'ImmutableMatrix': numpy.array}, "numpy"]) + assert (f(1) == array([[1, 2], [1, 2]])).all() + + +def test_lambdify_matrix_multi_input(): + M = sympy.Matrix([[x**2, x*y, x*z], + [y*x, y**2, y*z], + [z*x, z*y, z**2]]) + f = lambdify((x, y, z), M, [{'ImmutableMatrix': numpy.array}, "numpy"]) + + xh, yh, zh = 1.0, 2.0, 3.0 + expected = array([[xh**2, xh*yh, xh*zh], + [yh*xh, yh**2, yh*zh], + [zh*xh, zh*yh, zh**2]]) + actual = f(xh, yh, zh) + assert numpy.allclose(actual, expected) + + +def test_lambdify_matrix_vec_input(): + X = sympy.DeferredVector('X') + M = Matrix([ + [X[0]**2, X[0]*X[1], X[0]*X[2]], + [X[1]*X[0], X[1]**2, X[1]*X[2]], + [X[2]*X[0], X[2]*X[1], X[2]**2]]) + f = lambdify(X, M, [{'ImmutableMatrix': numpy.array}, "numpy"]) + + Xh = array([1.0, 2.0, 3.0]) + expected = array([[Xh[0]**2, Xh[0]*Xh[1], Xh[0]*Xh[2]], + [Xh[1]*Xh[0], Xh[1]**2, Xh[1]*Xh[2]], + [Xh[2]*Xh[0], Xh[2]*Xh[1], Xh[2]**2]]) + actual = f(Xh) + assert numpy.allclose(actual, expected) + + +def test_lambdify_transl(): + from sympy.utilities.lambdify import NUMPY_TRANSLATIONS + for sym, mat in NUMPY_TRANSLATIONS.items(): + assert sym in sympy.__dict__ + assert mat in numpy.__dict__ + + +def test_symarray(): + """Test creation of numpy arrays of SymPy symbols.""" + + import numpy as np + import numpy.testing as npt + + syms = symbols('_0,_1,_2') + s1 = symarray("", 3) + s2 = symarray("", 3) + npt.assert_array_equal(s1, np.array(syms, dtype=object)) + assert s1[0] == s2[0] + + a = symarray('a', 3) + b = symarray('b', 3) + assert not(a[0] == b[0]) + + asyms = symbols('a_0,a_1,a_2') + npt.assert_array_equal(a, np.array(asyms, dtype=object)) + + # Multidimensional checks + a2d = symarray('a', (2, 3)) + assert a2d.shape == (2, 3) + a00, a12 = symbols('a_0_0,a_1_2') + assert a2d[0, 0] == a00 + assert a2d[1, 2] == a12 + + a3d = symarray('a', (2, 3, 2)) + assert a3d.shape == (2, 3, 2) + a000, a120, a121 = symbols('a_0_0_0,a_1_2_0,a_1_2_1') + assert a3d[0, 0, 0] == a000 + assert a3d[1, 2, 0] == a120 + assert a3d[1, 2, 1] == a121 + + +def test_vectorize(): + assert (numpy.vectorize( + sin)([1, 2, 3]) == numpy.array([sin(1), sin(2), sin(3)])).all() diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_pythonmpq.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_pythonmpq.py new file mode 100644 index 0000000000000000000000000000000000000000..137cfdf5c858544f0811ae666f000cfb368787a0 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_pythonmpq.py @@ -0,0 +1,176 @@ +""" +test_pythonmpq.py + +Test the PythonMPQ class for consistency with gmpy2's mpq type. If gmpy2 is +installed run the same tests for both. +""" +from fractions import Fraction +from decimal import Decimal +import pickle +from typing import Callable, List, Tuple, Type + +from sympy.testing.pytest import raises + +from sympy.external.pythonmpq import PythonMPQ + +# +# If gmpy2 is installed then run the tests for both mpq and PythonMPQ. +# That should ensure consistency between the implementation here and mpq. +# +rational_types: List[Tuple[Callable, Type, Callable, Type]] +rational_types = [(PythonMPQ, PythonMPQ, int, int)] +try: + from gmpy2 import mpq, mpz + rational_types.append((mpq, type(mpq(1)), mpz, type(mpz(1)))) +except ImportError: + pass + + +def test_PythonMPQ(): + # + # Test PythonMPQ and also mpq if gmpy/gmpy2 is installed. + # + for Q, TQ, Z, TZ in rational_types: + + def check_Q(q): + assert isinstance(q, TQ) + assert isinstance(q.numerator, TZ) + assert isinstance(q.denominator, TZ) + return q.numerator, q.denominator + + # Check construction from different types + assert check_Q(Q(3)) == (3, 1) + assert check_Q(Q(3, 5)) == (3, 5) + assert check_Q(Q(Q(3, 5))) == (3, 5) + assert check_Q(Q(0.5)) == (1, 2) + assert check_Q(Q('0.5')) == (1, 2) + assert check_Q(Q(Fraction(3, 5))) == (3, 5) + + # https://github.com/aleaxit/gmpy/issues/327 + if Q is PythonMPQ: + assert check_Q(Q(Decimal('0.6'))) == (3, 5) + + # Invalid types + raises(TypeError, lambda: Q([])) + raises(TypeError, lambda: Q([], [])) + + # Check normalisation of signs + assert check_Q(Q(2, 3)) == (2, 3) + assert check_Q(Q(-2, 3)) == (-2, 3) + assert check_Q(Q(2, -3)) == (-2, 3) + assert check_Q(Q(-2, -3)) == (2, 3) + + # Check gcd calculation + assert check_Q(Q(12, 8)) == (3, 2) + + # __int__/__float__ + assert int(Q(5, 3)) == 1 + assert int(Q(-5, 3)) == -1 + assert float(Q(5, 2)) == 2.5 + assert float(Q(-5, 2)) == -2.5 + + # __str__/__repr__ + assert str(Q(2, 1)) == "2" + assert str(Q(1, 2)) == "1/2" + if Q is PythonMPQ: + assert repr(Q(2, 1)) == "MPQ(2,1)" + assert repr(Q(1, 2)) == "MPQ(1,2)" + else: + assert repr(Q(2, 1)) == "mpq(2,1)" + assert repr(Q(1, 2)) == "mpq(1,2)" + + # __bool__ + assert bool(Q(1, 2)) is True + assert bool(Q(0)) is False + + # __eq__/__ne__ + assert (Q(2, 3) == Q(2, 3)) is True + assert (Q(2, 3) == Q(2, 5)) is False + assert (Q(2, 3) != Q(2, 3)) is False + assert (Q(2, 3) != Q(2, 5)) is True + + # __hash__ + assert hash(Q(3, 5)) == hash(Fraction(3, 5)) + + # __reduce__ + q = Q(2, 3) + assert pickle.loads(pickle.dumps(q)) == q + + # __ge__/__gt__/__le__/__lt__ + assert (Q(1, 3) < Q(2, 3)) is True + assert (Q(2, 3) < Q(2, 3)) is False + assert (Q(2, 3) < Q(1, 3)) is False + assert (Q(-2, 3) < Q(1, 3)) is True + assert (Q(1, 3) < Q(-2, 3)) is False + + assert (Q(1, 3) <= Q(2, 3)) is True + assert (Q(2, 3) <= Q(2, 3)) is True + assert (Q(2, 3) <= Q(1, 3)) is False + assert (Q(-2, 3) <= Q(1, 3)) is True + assert (Q(1, 3) <= Q(-2, 3)) is False + + assert (Q(1, 3) > Q(2, 3)) is False + assert (Q(2, 3) > Q(2, 3)) is False + assert (Q(2, 3) > Q(1, 3)) is True + assert (Q(-2, 3) > Q(1, 3)) is False + assert (Q(1, 3) > Q(-2, 3)) is True + + assert (Q(1, 3) >= Q(2, 3)) is False + assert (Q(2, 3) >= Q(2, 3)) is True + assert (Q(2, 3) >= Q(1, 3)) is True + assert (Q(-2, 3) >= Q(1, 3)) is False + assert (Q(1, 3) >= Q(-2, 3)) is True + + # __abs__/__pos__/__neg__ + assert abs(Q(2, 3)) == abs(Q(-2, 3)) == Q(2, 3) + assert +Q(2, 3) == Q(2, 3) + assert -Q(2, 3) == Q(-2, 3) + + # __add__/__radd__ + assert Q(2, 3) + Q(5, 7) == Q(29, 21) + assert Q(2, 3) + 1 == Q(5, 3) + assert 1 + Q(2, 3) == Q(5, 3) + raises(TypeError, lambda: [] + Q(1)) + raises(TypeError, lambda: Q(1) + []) + + # __sub__/__rsub__ + assert Q(2, 3) - Q(5, 7) == Q(-1, 21) + assert Q(2, 3) - 1 == Q(-1, 3) + assert 1 - Q(2, 3) == Q(1, 3) + raises(TypeError, lambda: [] - Q(1)) + raises(TypeError, lambda: Q(1) - []) + + # __mul__/__rmul__ + assert Q(2, 3) * Q(5, 7) == Q(10, 21) + assert Q(2, 3) * 1 == Q(2, 3) + assert 1 * Q(2, 3) == Q(2, 3) + raises(TypeError, lambda: [] * Q(1)) + raises(TypeError, lambda: Q(1) * []) + + # __pow__/__rpow__ + assert Q(2, 3) ** 2 == Q(4, 9) + assert Q(2, 3) ** 1 == Q(2, 3) + assert Q(-2, 3) ** 2 == Q(4, 9) + assert Q(-2, 3) ** -1 == Q(-3, 2) + if Q is PythonMPQ: + raises(TypeError, lambda: 1 ** Q(2, 3)) + raises(TypeError, lambda: Q(1, 4) ** Q(1, 2)) + raises(TypeError, lambda: [] ** Q(1)) + raises(TypeError, lambda: Q(1) ** []) + + # __div__/__rdiv__ + assert Q(2, 3) / Q(5, 7) == Q(14, 15) + assert Q(2, 3) / 1 == Q(2, 3) + assert 1 / Q(2, 3) == Q(3, 2) + raises(TypeError, lambda: [] / Q(1)) + raises(TypeError, lambda: Q(1) / []) + raises(ZeroDivisionError, lambda: Q(1, 2) / Q(0)) + + # __divmod__ + if Q is PythonMPQ: + raises(TypeError, lambda: Q(2, 3) // Q(1, 3)) + raises(TypeError, lambda: Q(2, 3) % Q(1, 3)) + raises(TypeError, lambda: 1 // Q(1, 3)) + raises(TypeError, lambda: 1 % Q(1, 3)) + raises(TypeError, lambda: Q(2, 3) // 1) + raises(TypeError, lambda: Q(2, 3) % 1) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_scipy.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_scipy.py new file mode 100644 index 0000000000000000000000000000000000000000..3746d1a311eb68bb1af16e18ab152c7236b42bb5 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/external/tests/test_scipy.py @@ -0,0 +1,35 @@ +# This testfile tests SymPy <-> SciPy compatibility + +# Don't test any SymPy features here. Just pure interaction with SciPy. +# Always write regular SymPy tests for anything, that can be tested in pure +# Python (without scipy). Here we test everything, that a user may need when +# using SymPy with SciPy + +from sympy.external import import_module + +scipy = import_module('scipy') +if not scipy: + #bin/test will not execute any tests now + disabled = True + +from sympy.functions.special.bessel import jn_zeros + + +def eq(a, b, tol=1e-6): + for x, y in zip(a, b): + if not (abs(x - y) < tol): + return False + return True + + +def test_jn_zeros(): + assert eq(jn_zeros(0, 4, method="scipy"), + [3.141592, 6.283185, 9.424777, 12.566370]) + assert eq(jn_zeros(1, 4, method="scipy"), + [4.493409, 7.725251, 10.904121, 14.066193]) + assert eq(jn_zeros(2, 4, method="scipy"), + [5.763459, 9.095011, 12.322940, 15.514603]) + assert eq(jn_zeros(3, 4, method="scipy"), + [6.987932, 10.417118, 13.698023, 16.923621]) + assert eq(jn_zeros(4, 4, method="scipy"), + [8.182561, 11.704907, 15.039664, 18.301255]) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..ed93b2a11754aa26af5eef3932d177374b3ddfd6 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/__init__.py @@ -0,0 +1,115 @@ +"""A functions module, includes all the standard functions. + +Combinatorial - factorial, fibonacci, harmonic, bernoulli... +Elementary - hyperbolic, trigonometric, exponential, floor and ceiling, sqrt... +Special - gamma, zeta,spherical harmonics... +""" + +from sympy.functions.combinatorial.factorials import (factorial, factorial2, + rf, ff, binomial, RisingFactorial, FallingFactorial, subfactorial) +from sympy.functions.combinatorial.numbers import (carmichael, fibonacci, lucas, tribonacci, + harmonic, bernoulli, bell, euler, catalan, genocchi, andre, partition, divisor_sigma, + udivisor_sigma, legendre_symbol, jacobi_symbol, kronecker_symbol, mobius, + primenu, primeomega, totient, reduced_totient, primepi, motzkin) +from sympy.functions.elementary.miscellaneous import (sqrt, root, Min, Max, + Id, real_root, cbrt, Rem) +from sympy.functions.elementary.complexes import (re, im, sign, Abs, + conjugate, arg, polar_lift, periodic_argument, unbranched_argument, + principal_branch, transpose, adjoint, polarify, unpolarify) +from sympy.functions.elementary.trigonometric import (sin, cos, tan, + sec, csc, cot, sinc, asin, acos, atan, asec, acsc, acot, atan2) +from sympy.functions.elementary.exponential import (exp_polar, exp, log, + LambertW) +from sympy.functions.elementary.hyperbolic import (sinh, cosh, tanh, coth, + sech, csch, asinh, acosh, atanh, acoth, asech, acsch) +from sympy.functions.elementary.integers import floor, ceiling, frac +from sympy.functions.elementary.piecewise import (Piecewise, piecewise_fold, + piecewise_exclusive) +from sympy.functions.special.error_functions import (erf, erfc, erfi, erf2, + erfinv, erfcinv, erf2inv, Ei, expint, E1, li, Li, Si, Ci, Shi, Chi, + fresnels, fresnelc) +from sympy.functions.special.gamma_functions import (gamma, lowergamma, + uppergamma, polygamma, loggamma, digamma, trigamma, multigamma) +from sympy.functions.special.zeta_functions import (dirichlet_eta, zeta, + lerchphi, polylog, stieltjes, riemann_xi) +from sympy.functions.special.tensor_functions import (Eijk, LeviCivita, + KroneckerDelta) +from sympy.functions.special.singularity_functions import SingularityFunction +from sympy.functions.special.delta_functions import DiracDelta, Heaviside +from sympy.functions.special.bsplines import bspline_basis, bspline_basis_set, interpolating_spline +from sympy.functions.special.bessel import (besselj, bessely, besseli, besselk, + hankel1, hankel2, jn, yn, jn_zeros, hn1, hn2, airyai, airybi, airyaiprime, airybiprime, marcumq) +from sympy.functions.special.hyper import hyper, meijerg, appellf1 +from sympy.functions.special.polynomials import (legendre, assoc_legendre, + hermite, hermite_prob, chebyshevt, chebyshevu, chebyshevu_root, + chebyshevt_root, laguerre, assoc_laguerre, gegenbauer, jacobi, jacobi_normalized) +from sympy.functions.special.spherical_harmonics import Ynm, Ynm_c, Znm +from sympy.functions.special.elliptic_integrals import (elliptic_k, + elliptic_f, elliptic_e, elliptic_pi) +from sympy.functions.special.beta_functions import beta, betainc, betainc_regularized +from sympy.functions.special.mathieu_functions import (mathieus, mathieuc, + mathieusprime, mathieucprime) +ln = log + +__all__ = [ + 'factorial', 'factorial2', 'rf', 'ff', 'binomial', 'RisingFactorial', + 'FallingFactorial', 'subfactorial', + + 'carmichael', 'fibonacci', 'lucas', 'motzkin', 'tribonacci', 'harmonic', + 'bernoulli', 'bell', 'euler', 'catalan', 'genocchi', 'andre', 'partition', + 'divisor_sigma', 'udivisor_sigma', 'legendre_symbol', 'jacobi_symbol', 'kronecker_symbol', + 'mobius', 'primenu', 'primeomega', 'totient', 'reduced_totient', 'primepi', + + 'sqrt', 'root', 'Min', 'Max', 'Id', 'real_root', 'cbrt', 'Rem', + + 're', 'im', 'sign', 'Abs', 'conjugate', 'arg', 'polar_lift', + 'periodic_argument', 'unbranched_argument', 'principal_branch', + 'transpose', 'adjoint', 'polarify', 'unpolarify', + + 'sin', 'cos', 'tan', 'sec', 'csc', 'cot', 'sinc', 'asin', 'acos', 'atan', + 'asec', 'acsc', 'acot', 'atan2', + + 'exp_polar', 'exp', 'ln', 'log', 'LambertW', + + 'sinh', 'cosh', 'tanh', 'coth', 'sech', 'csch', 'asinh', 'acosh', 'atanh', + 'acoth', 'asech', 'acsch', + + 'floor', 'ceiling', 'frac', + + 'Piecewise', 'piecewise_fold', 'piecewise_exclusive', + + 'erf', 'erfc', 'erfi', 'erf2', 'erfinv', 'erfcinv', 'erf2inv', 'Ei', + 'expint', 'E1', 'li', 'Li', 'Si', 'Ci', 'Shi', 'Chi', 'fresnels', + 'fresnelc', + + 'gamma', 'lowergamma', 'uppergamma', 'polygamma', 'loggamma', 'digamma', + 'trigamma', 'multigamma', + + 'dirichlet_eta', 'zeta', 'lerchphi', 'polylog', 'stieltjes', 'riemann_xi', + + 'Eijk', 'LeviCivita', 'KroneckerDelta', + + 'SingularityFunction', + + 'DiracDelta', 'Heaviside', + + 'bspline_basis', 'bspline_basis_set', 'interpolating_spline', + + 'besselj', 'bessely', 'besseli', 'besselk', 'hankel1', 'hankel2', 'jn', + 'yn', 'jn_zeros', 'hn1', 'hn2', 'airyai', 'airybi', 'airyaiprime', + 'airybiprime', 'marcumq', + + 'hyper', 'meijerg', 'appellf1', + + 'legendre', 'assoc_legendre', 'hermite', 'hermite_prob', 'chebyshevt', + 'chebyshevu', 'chebyshevu_root', 'chebyshevt_root', 'laguerre', + 'assoc_laguerre', 'gegenbauer', 'jacobi', 'jacobi_normalized', + + 'Ynm', 'Ynm_c', 'Znm', + + 'elliptic_k', 'elliptic_f', 'elliptic_e', 'elliptic_pi', + + 'beta', 'betainc', 'betainc_regularized', + + 'mathieus', 'mathieuc', 'mathieusprime', 'mathieucprime', +] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..584b3c8d46b5c7600d85efc7db46d7aa190397f8 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/__init__.py @@ -0,0 +1 @@ +# Stub __init__.py for sympy.functions.combinatorial diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/factorials.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/factorials.py new file mode 100644 index 0000000000000000000000000000000000000000..0c6d2f09524debca29d3040b28a019127a244b33 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/factorials.py @@ -0,0 +1,1133 @@ +from __future__ import annotations +from functools import reduce + +from sympy.core import S, sympify, Dummy, Mod +from sympy.core.cache import cacheit +from sympy.core.function import DefinedFunction, ArgumentIndexError, PoleError +from sympy.core.logic import fuzzy_and +from sympy.core.numbers import Integer, pi, I +from sympy.core.relational import Eq +from sympy.external.gmpy import gmpy as _gmpy +from sympy.ntheory import sieve +from sympy.ntheory.residue_ntheory import binomial_mod +from sympy.polys.polytools import Poly + +from math import factorial as _factorial, prod, sqrt as _sqrt + +class CombinatorialFunction(DefinedFunction): + """Base class for combinatorial functions. """ + + def _eval_simplify(self, **kwargs): + from sympy.simplify.combsimp import combsimp + # combinatorial function with non-integer arguments is + # automatically passed to gammasimp + expr = combsimp(self) + measure = kwargs['measure'] + if measure(expr) <= kwargs['ratio']*measure(self): + return expr + return self + + +############################################################################### +######################## FACTORIAL and MULTI-FACTORIAL ######################## +############################################################################### + + +class factorial(CombinatorialFunction): + r"""Implementation of factorial function over nonnegative integers. + By convention (consistent with the gamma function and the binomial + coefficients), factorial of a negative integer is complex infinity. + + The factorial is very important in combinatorics where it gives + the number of ways in which `n` objects can be permuted. It also + arises in calculus, probability, number theory, etc. + + There is strict relation of factorial with gamma function. In + fact `n! = gamma(n+1)` for nonnegative integers. Rewrite of this + kind is very useful in case of combinatorial simplification. + + Computation of the factorial is done using two algorithms. For + small arguments a precomputed look up table is used. However for bigger + input algorithm Prime-Swing is used. It is the fastest algorithm + known and computes `n!` via prime factorization of special class + of numbers, called here the 'Swing Numbers'. + + Examples + ======== + + >>> from sympy import Symbol, factorial, S + >>> n = Symbol('n', integer=True) + + >>> factorial(0) + 1 + + >>> factorial(7) + 5040 + + >>> factorial(-2) + zoo + + >>> factorial(n) + factorial(n) + + >>> factorial(2*n) + factorial(2*n) + + >>> factorial(S(1)/2) + factorial(1/2) + + See Also + ======== + + factorial2, RisingFactorial, FallingFactorial + """ + + def fdiff(self, argindex=1): + from sympy.functions.special.gamma_functions import (gamma, polygamma) + if argindex == 1: + return gamma(self.args[0] + 1)*polygamma(0, self.args[0] + 1) + else: + raise ArgumentIndexError(self, argindex) + + _small_swing = [ + 1, 1, 1, 3, 3, 15, 5, 35, 35, 315, 63, 693, 231, 3003, 429, 6435, 6435, 109395, + 12155, 230945, 46189, 969969, 88179, 2028117, 676039, 16900975, 1300075, + 35102025, 5014575, 145422675, 9694845, 300540195, 300540195 + ] + + _small_factorials: list[int] = [] + + @classmethod + def _swing(cls, n): + if n < 33: + return cls._small_swing[n] + else: + N, primes = int(_sqrt(n)), [] + + for prime in sieve.primerange(3, N + 1): + p, q = 1, n + + while True: + q //= prime + + if q > 0: + if q & 1 == 1: + p *= prime + else: + break + + if p > 1: + primes.append(p) + + for prime in sieve.primerange(N + 1, n//3 + 1): + if (n // prime) & 1 == 1: + primes.append(prime) + + L_product = prod(sieve.primerange(n//2 + 1, n + 1)) + R_product = prod(primes) + + return L_product*R_product + + @classmethod + def _recursive(cls, n): + if n < 2: + return 1 + else: + return (cls._recursive(n//2)**2)*cls._swing(n) + + @classmethod + def eval(cls, n): + n = sympify(n) + + if n.is_Number: + if n.is_zero: + return S.One + elif n is S.Infinity: + return S.Infinity + elif n.is_Integer: + if n.is_negative: + return S.ComplexInfinity + else: + n = n.p + + if n < 20: + if not cls._small_factorials: + result = 1 + for i in range(1, 20): + result *= i + cls._small_factorials.append(result) + result = cls._small_factorials[n-1] + + # GMPY factorial is faster, use it when available + # + # XXX: There is a sympy.external.gmpy.factorial function + # which provides gmpy.fac if available or the flint version + # if flint is used. It could be used here to avoid the + # conditional logic but it needs to be checked whether the + # pure Python fallback used there is as fast as the + # fallback used here (perhaps the fallback here should be + # moved to sympy.external.ntheory). + elif _gmpy is not None: + result = _gmpy.fac(n) + + else: + bits = bin(n).count('1') + result = cls._recursive(n)*2**(n - bits) + + return Integer(result) + + def _facmod(self, n, q): + res, N = 1, int(_sqrt(n)) + + # Exponent of prime p in n! is e_p(n) = [n/p] + [n/p**2] + ... + # for p > sqrt(n), e_p(n) < sqrt(n), the primes with [n/p] = m, + # occur consecutively and are grouped together in pw[m] for + # simultaneous exponentiation at a later stage + pw = [1]*N + + m = 2 # to initialize the if condition below + for prime in sieve.primerange(2, n + 1): + if m > 1: + m, y = 0, n // prime + while y: + m += y + y //= prime + if m < N: + pw[m] = pw[m]*prime % q + else: + res = res*pow(prime, m, q) % q + + for ex, bs in enumerate(pw): + if ex == 0 or bs == 1: + continue + if bs == 0: + return 0 + res = res*pow(bs, ex, q) % q + + return res + + def _eval_Mod(self, q): + n = self.args[0] + if n.is_integer and n.is_nonnegative and q.is_integer: + aq = abs(q) + d = aq - n + if d.is_nonpositive: + return S.Zero + else: + isprime = aq.is_prime + if d == 1: + # Apply Wilson's theorem (if a natural number n > 1 + # is a prime number, then (n-1)! = -1 mod n) and + # its inverse (if n > 4 is a composite number, then + # (n-1)! = 0 mod n) + if isprime: + return -1 % q + elif isprime is False and (aq - 6).is_nonnegative: + return S.Zero + elif n.is_Integer and q.is_Integer: + n, d, aq = map(int, (n, d, aq)) + if isprime and (d - 1 < n): + fc = self._facmod(d - 1, aq) + fc = pow(fc, aq - 2, aq) + if d%2: + fc = -fc + else: + fc = self._facmod(n, aq) + + return fc % q + + def _eval_rewrite_as_gamma(self, n, piecewise=True, **kwargs): + from sympy.functions.special.gamma_functions import gamma + return gamma(n + 1) + + def _eval_rewrite_as_Product(self, n, **kwargs): + from sympy.concrete.products import Product + if n.is_nonnegative and n.is_integer: + i = Dummy('i', integer=True) + return Product(i, (i, 1, n)) + + def _eval_is_integer(self): + if self.args[0].is_integer and self.args[0].is_nonnegative: + return True + + def _eval_is_positive(self): + if self.args[0].is_integer and self.args[0].is_nonnegative: + return True + + def _eval_is_even(self): + x = self.args[0] + if x.is_integer and x.is_nonnegative: + return (x - 2).is_nonnegative + + def _eval_is_composite(self): + x = self.args[0] + if x.is_integer and x.is_nonnegative: + return (x - 3).is_nonnegative + + def _eval_is_real(self): + x = self.args[0] + if x.is_nonnegative or x.is_noninteger: + return True + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x) + arg0 = arg.subs(x, 0) + if arg0.is_zero: + return S.One + elif not arg0.is_infinite: + return self.func(arg) + raise PoleError("Cannot expand %s around 0" % (self)) + +class MultiFactorial(CombinatorialFunction): + pass + + +class subfactorial(CombinatorialFunction): + r"""The subfactorial counts the derangements of $n$ items and is + defined for non-negative integers as: + + .. math:: !n = \begin{cases} 1 & n = 0 \\ 0 & n = 1 \\ + (n-1)(!(n-1) + !(n-2)) & n > 1 \end{cases} + + It can also be written as ``int(round(n!/exp(1)))`` but the + recursive definition with caching is implemented for this function. + + An interesting analytic expression is the following [2]_ + + .. math:: !x = \Gamma(x + 1, -1)/e + + which is valid for non-negative integers `x`. The above formula + is not very useful in case of non-integers. `\Gamma(x + 1, -1)` is + single-valued only for integral arguments `x`, elsewhere on the positive + real axis it has an infinite number of branches none of which are real. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Subfactorial + .. [2] https://mathworld.wolfram.com/Subfactorial.html + + Examples + ======== + + >>> from sympy import subfactorial + >>> from sympy.abc import n + >>> subfactorial(n + 1) + subfactorial(n + 1) + >>> subfactorial(5) + 44 + + See Also + ======== + + factorial, uppergamma, + sympy.utilities.iterables.generate_derangements + """ + + @classmethod + @cacheit + def _eval(self, n): + if not n: + return S.One + elif n == 1: + return S.Zero + else: + z1, z2 = 1, 0 + for i in range(2, n + 1): + z1, z2 = z2, (i - 1)*(z2 + z1) + return z2 + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg.is_Integer and arg.is_nonnegative: + return cls._eval(arg) + elif arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Infinity + + def _eval_is_even(self): + if self.args[0].is_odd and self.args[0].is_nonnegative: + return True + + def _eval_is_integer(self): + if self.args[0].is_integer and self.args[0].is_nonnegative: + return True + + def _eval_rewrite_as_factorial(self, arg, **kwargs): + from sympy.concrete.summations import summation + i = Dummy('i') + f = S.NegativeOne**i / factorial(i) + return factorial(arg) * summation(f, (i, 0, arg)) + + def _eval_rewrite_as_gamma(self, arg, piecewise=True, **kwargs): + from sympy.functions.elementary.exponential import exp + from sympy.functions.special.gamma_functions import (gamma, lowergamma) + return (S.NegativeOne**(arg + 1)*exp(-I*pi*arg)*lowergamma(arg + 1, -1) + + gamma(arg + 1))*exp(-1) + + def _eval_rewrite_as_uppergamma(self, arg, **kwargs): + from sympy.functions.special.gamma_functions import uppergamma + return uppergamma(arg + 1, -1)/S.Exp1 + + def _eval_is_nonnegative(self): + if self.args[0].is_integer and self.args[0].is_nonnegative: + return True + + def _eval_is_odd(self): + if self.args[0].is_even and self.args[0].is_nonnegative: + return True + + +class factorial2(CombinatorialFunction): + r"""The double factorial `n!!`, not to be confused with `(n!)!` + + The double factorial is defined for nonnegative integers and for odd + negative integers as: + + .. math:: n!! = \begin{cases} 1 & n = 0 \\ + n(n-2)(n-4) \cdots 1 & n\ \text{positive odd} \\ + n(n-2)(n-4) \cdots 2 & n\ \text{positive even} \\ + (n+2)!!/(n+2) & n\ \text{negative odd} \end{cases} + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Double_factorial + + Examples + ======== + + >>> from sympy import factorial2, var + >>> n = var('n') + >>> n + n + >>> factorial2(n + 1) + factorial2(n + 1) + >>> factorial2(5) + 15 + >>> factorial2(-1) + 1 + >>> factorial2(-5) + 1/3 + + See Also + ======== + + factorial, RisingFactorial, FallingFactorial + """ + + @classmethod + def eval(cls, arg): + # TODO: extend this to complex numbers? + + if arg.is_Number: + if not arg.is_Integer: + raise ValueError("argument must be nonnegative integer " + "or negative odd integer") + + # This implementation is faster than the recursive one + # It also avoids "maximum recursion depth exceeded" runtime error + if arg.is_nonnegative: + if arg.is_even: + k = arg / 2 + return 2**k * factorial(k) + return factorial(arg) / factorial2(arg - 1) + + + if arg.is_odd: + return arg*(S.NegativeOne)**((1 - arg)/2) / factorial2(-arg) + raise ValueError("argument must be nonnegative integer " + "or negative odd integer") + + + def _eval_is_even(self): + # Double factorial is even for every positive even input + n = self.args[0] + if n.is_integer: + if n.is_odd: + return False + if n.is_even: + if n.is_positive: + return True + if n.is_zero: + return False + + def _eval_is_integer(self): + # Double factorial is an integer for every nonnegative input, and for + # -1 and -3 + n = self.args[0] + if n.is_integer: + if (n + 1).is_nonnegative: + return True + if n.is_odd: + return (n + 3).is_nonnegative + + def _eval_is_odd(self): + # Double factorial is odd for every odd input not smaller than -3, and + # for 0 + n = self.args[0] + if n.is_odd: + return (n + 3).is_nonnegative + if n.is_even: + if n.is_positive: + return False + if n.is_zero: + return True + + def _eval_is_positive(self): + # Double factorial is positive for every nonnegative input, and for + # every odd negative input which is of the form -1-4k for an + # nonnegative integer k + n = self.args[0] + if n.is_integer: + if (n + 1).is_nonnegative: + return True + if n.is_odd: + return ((n + 1) / 2).is_even + + def _eval_rewrite_as_gamma(self, n, piecewise=True, **kwargs): + from sympy.functions.elementary.miscellaneous import sqrt + from sympy.functions.elementary.piecewise import Piecewise + from sympy.functions.special.gamma_functions import gamma + return 2**(n/2)*gamma(n/2 + 1) * Piecewise((1, Eq(Mod(n, 2), 0)), + (sqrt(2/pi), Eq(Mod(n, 2), 1))) + + +############################################################################### +######################## RISING and FALLING FACTORIALS ######################## +############################################################################### + + +class RisingFactorial(CombinatorialFunction): + r""" + Rising factorial (also called Pochhammer symbol [1]_) is a double valued + function arising in concrete mathematics, hypergeometric functions + and series expansions. It is defined by: + + .. math:: \texttt{rf(y, k)} = (x)^k = x \cdot (x+1) \cdots (x+k-1) + + where `x` can be arbitrary expression and `k` is an integer. For + more information check "Concrete mathematics" by Graham, pp. 66 + or visit https://mathworld.wolfram.com/RisingFactorial.html page. + + When `x` is a `~.Poly` instance of degree $\ge 1$ with a single variable, + `(x)^k = x(y) \cdot x(y+1) \cdots x(y+k-1)`, where `y` is the + variable of `x`. This is as described in [2]_. + + Examples + ======== + + >>> from sympy import rf, Poly + >>> from sympy.abc import x + >>> rf(x, 0) + 1 + >>> rf(1, 5) + 120 + >>> rf(x, 5) == x*(1 + x)*(2 + x)*(3 + x)*(4 + x) + True + >>> rf(Poly(x**3, x), 2) + Poly(x**6 + 3*x**5 + 3*x**4 + x**3, x, domain='ZZ') + + Rewriting is complicated unless the relationship between + the arguments is known, but rising factorial can + be rewritten in terms of gamma, factorial, binomial, + and falling factorial. + + >>> from sympy import Symbol, factorial, ff, binomial, gamma + >>> n = Symbol('n', integer=True, positive=True) + >>> R = rf(n, n + 2) + >>> for i in (rf, ff, factorial, binomial, gamma): + ... R.rewrite(i) + ... + RisingFactorial(n, n + 2) + FallingFactorial(2*n + 1, n + 2) + factorial(2*n + 1)/factorial(n - 1) + binomial(2*n + 1, n + 2)*factorial(n + 2) + gamma(2*n + 2)/gamma(n) + + See Also + ======== + + factorial, factorial2, FallingFactorial + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Pochhammer_symbol + .. [2] Peter Paule, "Greatest Factorial Factorization and Symbolic + Summation", Journal of Symbolic Computation, vol. 20, pp. 235-268, + 1995. + + """ + + @classmethod + def eval(cls, x, k): + x = sympify(x) + k = sympify(k) + + if x is S.NaN or k is S.NaN: + return S.NaN + elif x is S.One: + return factorial(k) + elif k.is_Integer: + if k.is_zero: + return S.One + else: + if k.is_positive: + if x is S.Infinity: + return S.Infinity + elif x is S.NegativeInfinity: + if k.is_odd: + return S.NegativeInfinity + else: + return S.Infinity + else: + if isinstance(x, Poly): + gens = x.gens + if len(gens)!= 1: + raise ValueError("rf only defined for " + "polynomials on one generator") + else: + return reduce(lambda r, i: + r*(x.shift(i)), + range(int(k)), 1) + else: + return reduce(lambda r, i: r*(x + i), + range(int(k)), 1) + + else: + if x is S.Infinity: + return S.Infinity + elif x is S.NegativeInfinity: + return S.Infinity + else: + if isinstance(x, Poly): + gens = x.gens + if len(gens)!= 1: + raise ValueError("rf only defined for " + "polynomials on one generator") + else: + return 1/reduce(lambda r, i: + r*(x.shift(-i)), + range(1, abs(int(k)) + 1), 1) + else: + return 1/reduce(lambda r, i: + r*(x - i), + range(1, abs(int(k)) + 1), 1) + + if k.is_integer == False: + if x.is_integer and x.is_negative: + return S.Zero + + def _eval_rewrite_as_gamma(self, x, k, piecewise=True, **kwargs): + from sympy.functions.elementary.piecewise import Piecewise + from sympy.functions.special.gamma_functions import gamma + if not piecewise: + if (x <= 0) == True: + return S.NegativeOne**k*gamma(1 - x) / gamma(-k - x + 1) + return gamma(x + k) / gamma(x) + return Piecewise( + (gamma(x + k) / gamma(x), x > 0), + (S.NegativeOne**k*gamma(1 - x) / gamma(-k - x + 1), True)) + + def _eval_rewrite_as_FallingFactorial(self, x, k, **kwargs): + return FallingFactorial(x + k - 1, k) + + def _eval_rewrite_as_factorial(self, x, k, **kwargs): + from sympy.functions.elementary.piecewise import Piecewise + if x.is_integer and k.is_integer: + return Piecewise( + (factorial(k + x - 1)/factorial(x - 1), x > 0), + (S.NegativeOne**k*factorial(-x)/factorial(-k - x), True)) + + def _eval_rewrite_as_binomial(self, x, k, **kwargs): + if k.is_integer: + return factorial(k) * binomial(x + k - 1, k) + + def _eval_rewrite_as_tractable(self, x, k, limitvar=None, **kwargs): + from sympy.functions.special.gamma_functions import gamma + if limitvar: + k_lim = k.subs(limitvar, S.Infinity) + if k_lim is S.Infinity: + return (gamma(x + k).rewrite('tractable', deep=True) / gamma(x)) + elif k_lim is S.NegativeInfinity: + return (S.NegativeOne**k*gamma(1 - x) / gamma(-k - x + 1).rewrite('tractable', deep=True)) + return self.rewrite(gamma).rewrite('tractable', deep=True) + + def _eval_is_integer(self): + return fuzzy_and((self.args[0].is_integer, self.args[1].is_integer, + self.args[1].is_nonnegative)) + + +class FallingFactorial(CombinatorialFunction): + r""" + Falling factorial (related to rising factorial) is a double valued + function arising in concrete mathematics, hypergeometric functions + and series expansions. It is defined by + + .. math:: \texttt{ff(x, k)} = (x)_k = x \cdot (x-1) \cdots (x-k+1) + + where `x` can be arbitrary expression and `k` is an integer. For + more information check "Concrete mathematics" by Graham, pp. 66 + or [1]_. + + When `x` is a `~.Poly` instance of degree $\ge 1$ with single variable, + `(x)_k = x(y) \cdot x(y-1) \cdots x(y-k+1)`, where `y` is the + variable of `x`. This is as described in + + >>> from sympy import ff, Poly, Symbol + >>> from sympy.abc import x + >>> n = Symbol('n', integer=True) + + >>> ff(x, 0) + 1 + >>> ff(5, 5) + 120 + >>> ff(x, 5) == x*(x - 1)*(x - 2)*(x - 3)*(x - 4) + True + >>> ff(Poly(x**2, x), 2) + Poly(x**4 - 2*x**3 + x**2, x, domain='ZZ') + >>> ff(n, n) + factorial(n) + + Rewriting is complicated unless the relationship between + the arguments is known, but falling factorial can + be rewritten in terms of gamma, factorial and binomial + and rising factorial. + + >>> from sympy import factorial, rf, gamma, binomial, Symbol + >>> n = Symbol('n', integer=True, positive=True) + >>> F = ff(n, n - 2) + >>> for i in (rf, ff, factorial, binomial, gamma): + ... F.rewrite(i) + ... + RisingFactorial(3, n - 2) + FallingFactorial(n, n - 2) + factorial(n)/2 + binomial(n, n - 2)*factorial(n - 2) + gamma(n + 1)/2 + + See Also + ======== + + factorial, factorial2, RisingFactorial + + References + ========== + + .. [1] https://mathworld.wolfram.com/FallingFactorial.html + .. [2] Peter Paule, "Greatest Factorial Factorization and Symbolic + Summation", Journal of Symbolic Computation, vol. 20, pp. 235-268, + 1995. + + """ + + @classmethod + def eval(cls, x, k): + x = sympify(x) + k = sympify(k) + + if x is S.NaN or k is S.NaN: + return S.NaN + elif k.is_integer and x == k: + return factorial(x) + elif k.is_Integer: + if k.is_zero: + return S.One + else: + if k.is_positive: + if x is S.Infinity: + return S.Infinity + elif x is S.NegativeInfinity: + if k.is_odd: + return S.NegativeInfinity + else: + return S.Infinity + else: + if isinstance(x, Poly): + gens = x.gens + if len(gens)!= 1: + raise ValueError("ff only defined for " + "polynomials on one generator") + else: + return reduce(lambda r, i: + r*(x.shift(-i)), + range(int(k)), 1) + else: + return reduce(lambda r, i: r*(x - i), + range(int(k)), 1) + else: + if x is S.Infinity: + return S.Infinity + elif x is S.NegativeInfinity: + return S.Infinity + else: + if isinstance(x, Poly): + gens = x.gens + if len(gens)!= 1: + raise ValueError("rf only defined for " + "polynomials on one generator") + else: + return 1/reduce(lambda r, i: + r*(x.shift(i)), + range(1, abs(int(k)) + 1), 1) + else: + return 1/reduce(lambda r, i: r*(x + i), + range(1, abs(int(k)) + 1), 1) + + def _eval_rewrite_as_gamma(self, x, k, piecewise=True, **kwargs): + from sympy.functions.elementary.piecewise import Piecewise + from sympy.functions.special.gamma_functions import gamma + if not piecewise: + if (x < 0) == True: + return S.NegativeOne**k*gamma(k - x) / gamma(-x) + return gamma(x + 1) / gamma(x - k + 1) + return Piecewise( + (gamma(x + 1) / gamma(x - k + 1), x >= 0), + (S.NegativeOne**k*gamma(k - x) / gamma(-x), True)) + + def _eval_rewrite_as_RisingFactorial(self, x, k, **kwargs): + return rf(x - k + 1, k) + + def _eval_rewrite_as_binomial(self, x, k, **kwargs): + if k.is_integer: + return factorial(k) * binomial(x, k) + + def _eval_rewrite_as_factorial(self, x, k, **kwargs): + from sympy.functions.elementary.piecewise import Piecewise + if x.is_integer and k.is_integer: + return Piecewise( + (factorial(x)/factorial(-k + x), x >= 0), + (S.NegativeOne**k*factorial(k - x - 1)/factorial(-x - 1), True)) + + def _eval_rewrite_as_tractable(self, x, k, limitvar=None, **kwargs): + from sympy.functions.special.gamma_functions import gamma + if limitvar: + k_lim = k.subs(limitvar, S.Infinity) + if k_lim is S.Infinity: + return (S.NegativeOne**k*gamma(k - x).rewrite('tractable', deep=True) / gamma(-x)) + elif k_lim is S.NegativeInfinity: + return (gamma(x + 1) / gamma(x - k + 1).rewrite('tractable', deep=True)) + return self.rewrite(gamma).rewrite('tractable', deep=True) + + def _eval_is_integer(self): + return fuzzy_and((self.args[0].is_integer, self.args[1].is_integer, + self.args[1].is_nonnegative)) + + +rf = RisingFactorial +ff = FallingFactorial + +############################################################################### +########################### BINOMIAL COEFFICIENTS ############################# +############################################################################### + + +class binomial(CombinatorialFunction): + r"""Implementation of the binomial coefficient. It can be defined + in two ways depending on its desired interpretation: + + .. math:: \binom{n}{k} = \frac{n!}{k!(n-k)!}\ \text{or}\ + \binom{n}{k} = \frac{(n)_k}{k!} + + First, in a strict combinatorial sense it defines the + number of ways we can choose `k` elements from a set of + `n` elements. In this case both arguments are nonnegative + integers and binomial is computed using an efficient + algorithm based on prime factorization. + + The other definition is generalization for arbitrary `n`, + however `k` must also be nonnegative. This case is very + useful when evaluating summations. + + For the sake of convenience, for negative integer `k` this function + will return zero no matter the other argument. + + To expand the binomial when `n` is a symbol, use either + ``expand_func()`` or ``expand(func=True)``. The former will keep + the polynomial in factored form while the latter will expand the + polynomial itself. See examples for details. + + Examples + ======== + + >>> from sympy import Symbol, Rational, binomial, expand_func + >>> n = Symbol('n', integer=True, positive=True) + + >>> binomial(15, 8) + 6435 + + >>> binomial(n, -1) + 0 + + Rows of Pascal's triangle can be generated with the binomial function: + + >>> for N in range(8): + ... print([binomial(N, i) for i in range(N + 1)]) + ... + [1] + [1, 1] + [1, 2, 1] + [1, 3, 3, 1] + [1, 4, 6, 4, 1] + [1, 5, 10, 10, 5, 1] + [1, 6, 15, 20, 15, 6, 1] + [1, 7, 21, 35, 35, 21, 7, 1] + + As can a given diagonal, e.g. the 4th diagonal: + + >>> N = -4 + >>> [binomial(N, i) for i in range(1 - N)] + [1, -4, 10, -20, 35] + + >>> binomial(Rational(5, 4), 3) + -5/128 + >>> binomial(Rational(-5, 4), 3) + -195/128 + + >>> binomial(n, 3) + binomial(n, 3) + + >>> binomial(n, 3).expand(func=True) + n**3/6 - n**2/2 + n/3 + + >>> expand_func(binomial(n, 3)) + n*(n - 2)*(n - 1)/6 + + In many cases, we can also compute binomial coefficients modulo a + prime p quickly using Lucas' Theorem [2]_, though we need to include + `evaluate=False` to postpone evaluation: + + >>> from sympy import Mod + >>> Mod(binomial(156675, 4433, evaluate=False), 10**5 + 3) + 28625 + + Using a generalisation of Lucas's Theorem given by Granville [3]_, + we can extend this to arbitrary n: + + >>> Mod(binomial(10**18, 10**12, evaluate=False), (10**5 + 3)**2) + 3744312326 + + References + ========== + + .. [1] https://www.johndcook.com/blog/binomial_coefficients/ + .. [2] https://en.wikipedia.org/wiki/Lucas%27s_theorem + .. [3] Binomial coefficients modulo prime powers, Andrew Granville, + Available: https://web.archive.org/web/20170202003812/http://www.dms.umontreal.ca/~andrew/PDF/BinCoeff.pdf + """ + + def fdiff(self, argindex=1): + from sympy.functions.special.gamma_functions import polygamma + if argindex == 1: + # https://functions.wolfram.com/GammaBetaErf/Binomial/20/01/01/ + n, k = self.args + return binomial(n, k)*(polygamma(0, n + 1) - \ + polygamma(0, n - k + 1)) + elif argindex == 2: + # https://functions.wolfram.com/GammaBetaErf/Binomial/20/01/02/ + n, k = self.args + return binomial(n, k)*(polygamma(0, n - k + 1) - \ + polygamma(0, k + 1)) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def _eval(self, n, k): + # n.is_Number and k.is_Integer and k != 1 and n != k + + if k.is_Integer: + if n.is_Integer and n >= 0: + n, k = int(n), int(k) + + if k > n: + return S.Zero + elif k > n // 2: + k = n - k + + # XXX: This conditional logic should be moved to + # sympy.external.gmpy and the pure Python version of bincoef + # should be moved to sympy.external.ntheory. + if _gmpy is not None: + return Integer(_gmpy.bincoef(n, k)) + + d, result = n - k, 1 + for i in range(1, k + 1): + d += 1 + result = result * d // i + return Integer(result) + else: + d, result = n - k, 1 + for i in range(1, k + 1): + d += 1 + result *= d + return result / _factorial(k) + + @classmethod + def eval(cls, n, k): + n, k = map(sympify, (n, k)) + d = n - k + n_nonneg, n_isint = n.is_nonnegative, n.is_integer + if k.is_zero or ((n_nonneg or n_isint is False) + and d.is_zero): + return S.One + if (k - 1).is_zero or ((n_nonneg or n_isint is False) + and (d - 1).is_zero): + return n + if k.is_integer: + if k.is_negative or (n_nonneg and n_isint and d.is_negative): + return S.Zero + elif n.is_number: + res = cls._eval(n, k) + return res.expand(basic=True) if res else res + elif n_nonneg is False and n_isint: + # a special case when binomial evaluates to complex infinity + return S.ComplexInfinity + elif k.is_number: + from sympy.functions.special.gamma_functions import gamma + return gamma(n + 1)/(gamma(k + 1)*gamma(n - k + 1)) + + def _eval_Mod(self, q): + n, k = self.args + + if any(x.is_integer is False for x in (n, k, q)): + raise ValueError("Integers expected for binomial Mod") + + if all(x.is_Integer for x in (n, k, q)): + n, k = map(int, (n, k)) + aq, res = abs(q), 1 + + # handle negative integers k or n + if k < 0: + return S.Zero + if n < 0: + n = -n + k - 1 + res = -1 if k%2 else 1 + + # non negative integers k and n + if k > n: + return S.Zero + + isprime = aq.is_prime + aq = int(aq) + if isprime: + if aq < n: + # use Lucas Theorem + N, K = n, k + while N or K: + res = res*binomial(N % aq, K % aq) % aq + N, K = N // aq, K // aq + + else: + # use Factorial Modulo + d = n - k + if k > d: + k, d = d, k + kf = 1 + for i in range(2, k + 1): + kf = kf*i % aq + df = kf + for i in range(k + 1, d + 1): + df = df*i % aq + res *= df + for i in range(d + 1, n + 1): + res = res*i % aq + + res *= pow(kf*df % aq, aq - 2, aq) + res %= aq + + elif _sqrt(q) < k and q != 1: + res = binomial_mod(n, k, q) + + else: + # Binomial Factorization is performed by calculating the + # exponents of primes <= n in `n! /(k! (n - k)!)`, + # for non-negative integers n and k. As the exponent of + # prime in n! is e_p(n) = [n/p] + [n/p**2] + ... + # the exponent of prime in binomial(n, k) would be + # e_p(n) - e_p(k) - e_p(n - k) + M = int(_sqrt(n)) + for prime in sieve.primerange(2, n + 1): + if prime > n - k: + res = res*prime % aq + elif prime > n // 2: + continue + elif prime > M: + if n % prime < k % prime: + res = res*prime % aq + else: + N, K = n, k + exp = a = 0 + + while N > 0: + a = int((N % prime) < (K % prime + a)) + N, K = N // prime, K // prime + exp += a + + if exp > 0: + res *= pow(prime, exp, aq) + res %= aq + + return S(res % q) + + def _eval_expand_func(self, **hints): + """ + Function to expand binomial(n, k) when m is positive integer + Also, + n is self.args[0] and k is self.args[1] while using binomial(n, k) + """ + n = self.args[0] + if n.is_Number: + return binomial(*self.args) + + k = self.args[1] + if (n-k).is_Integer: + k = n - k + + if k.is_Integer: + if k.is_zero: + return S.One + elif k.is_negative: + return S.Zero + else: + n, result = self.args[0], 1 + for i in range(1, k + 1): + result *= n - k + i + return result / _factorial(k) + else: + return binomial(*self.args) + + def _eval_rewrite_as_factorial(self, n, k, **kwargs): + return factorial(n)/(factorial(k)*factorial(n - k)) + + def _eval_rewrite_as_gamma(self, n, k, piecewise=True, **kwargs): + from sympy.functions.special.gamma_functions import gamma + return gamma(n + 1)/(gamma(k + 1)*gamma(n - k + 1)) + + def _eval_rewrite_as_tractable(self, n, k, limitvar=None, **kwargs): + return self._eval_rewrite_as_gamma(n, k).rewrite('tractable') + + def _eval_rewrite_as_FallingFactorial(self, n, k, **kwargs): + if k.is_integer: + return ff(n, k) / factorial(k) + + def _eval_is_integer(self): + n, k = self.args + if n.is_integer and k.is_integer: + return True + elif k.is_integer is False: + return False + + def _eval_is_nonnegative(self): + n, k = self.args + if n.is_integer and k.is_integer: + if n.is_nonnegative or k.is_negative or k.is_even: + return True + elif k.is_even is False: + return False + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.functions.special.gamma_functions import gamma + return self.rewrite(gamma)._eval_as_leading_term(x, logx=logx, cdir=cdir) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/numbers.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/numbers.py new file mode 100644 index 0000000000000000000000000000000000000000..c0dfc518d4a6784712341edaa5731145469a8d1e --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/numbers.py @@ -0,0 +1,3196 @@ +""" +This module implements some special functions that commonly appear in +combinatorial contexts (e.g. in power series); in particular, +sequences of rational numbers such as Bernoulli and Fibonacci numbers. + +Factorials, binomial coefficients and related functions are located in +the separate 'factorials' module. +""" +from __future__ import annotations +from math import prod +from collections import defaultdict +from typing import Callable + +from sympy.core import S, Symbol, Add, Dummy +from sympy.core.cache import cacheit +from sympy.core.containers import Dict +from sympy.core.expr import Expr +from sympy.core.function import ArgumentIndexError, DefinedFunction, expand_mul +from sympy.core.logic import fuzzy_not +from sympy.core.mul import Mul +from sympy.core.numbers import E, I, pi, oo, Rational, Integer +from sympy.core.relational import Eq, is_le, is_gt, is_lt +from sympy.external.gmpy import SYMPY_INTS, remove, lcm, legendre, jacobi, kronecker +from sympy.functions.combinatorial.factorials import (binomial, + factorial, subfactorial) +from sympy.functions.elementary.exponential import log +from sympy.functions.elementary.piecewise import Piecewise +from sympy.ntheory.factor_ import (factorint, _divisor_sigma, is_carmichael, + find_carmichael_numbers_in_range, find_first_n_carmichaels) +from sympy.ntheory.generate import _primepi +from sympy.ntheory.partitions_ import _partition, _partition_rec +from sympy.ntheory.primetest import isprime, is_square +from sympy.polys.appellseqs import bernoulli_poly, euler_poly, genocchi_poly +from sympy.polys.polytools import cancel +from sympy.utilities.enumerative import MultisetPartitionTraverser +from sympy.utilities.exceptions import sympy_deprecation_warning +from sympy.utilities.iterables import multiset, multiset_derangements, iterable +from sympy.utilities.memoization import recurrence_memo +from sympy.utilities.misc import as_int + +from mpmath import mp, workprec +from mpmath.libmp import ifib as _ifib + + +def _product(a, b): + return prod(range(a, b + 1)) + + +# Dummy symbol used for computing polynomial sequences +_sym = Symbol('x') + + +#----------------------------------------------------------------------------# +# # +# Carmichael numbers # +# # +#----------------------------------------------------------------------------# + +class carmichael(DefinedFunction): + r""" + Carmichael Numbers: + + Certain cryptographic algorithms make use of big prime numbers. + However, checking whether a big number is prime is not so easy. + Randomized prime number checking tests exist that offer a high degree of + confidence of accurate determination at low cost, such as the Fermat test. + + Let 'a' be a random number between $2$ and $n - 1$, where $n$ is the + number whose primality we are testing. Then, $n$ is probably prime if it + satisfies the modular arithmetic congruence relation: + + .. math :: a^{n-1} = 1 \pmod{n} + + (where mod refers to the modulo operation) + + If a number passes the Fermat test several times, then it is prime with a + high probability. + + Unfortunately, certain composite numbers (non-primes) still pass the Fermat + test with every number smaller than themselves. + These numbers are called Carmichael numbers. + + A Carmichael number will pass a Fermat primality test to every base $b$ + relatively prime to the number, even though it is not actually prime. + This makes tests based on Fermat's Little Theorem less effective than + strong probable prime tests such as the Baillie-PSW primality test and + the Miller-Rabin primality test. + + Examples + ======== + + >>> from sympy.ntheory.factor_ import find_first_n_carmichaels, find_carmichael_numbers_in_range + >>> find_first_n_carmichaels(5) + [561, 1105, 1729, 2465, 2821] + >>> find_carmichael_numbers_in_range(0, 562) + [561] + >>> find_carmichael_numbers_in_range(0,1000) + [561] + >>> find_carmichael_numbers_in_range(0,2000) + [561, 1105, 1729] + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Carmichael_number + .. [2] https://en.wikipedia.org/wiki/Fermat_primality_test + .. [3] https://www.jstor.org/stable/23248683?seq=1#metadata_info_tab_contents + """ + + @staticmethod + def is_perfect_square(n): + sympy_deprecation_warning( + """ +is_perfect_square is just a wrapper around sympy.ntheory.primetest.is_square +so use that directly instead. + """, + deprecated_since_version="1.11", + active_deprecations_target='deprecated-carmichael-static-methods', + ) + return is_square(n) + + @staticmethod + def divides(p, n): + sympy_deprecation_warning( + """ + divides can be replaced by directly testing n % p == 0. + """, + deprecated_since_version="1.11", + active_deprecations_target='deprecated-carmichael-static-methods', + ) + return n % p == 0 + + @staticmethod + def is_prime(n): + sympy_deprecation_warning( + """ +is_prime is just a wrapper around sympy.ntheory.primetest.isprime so use that +directly instead. + """, + deprecated_since_version="1.11", + active_deprecations_target='deprecated-carmichael-static-methods', + ) + return isprime(n) + + @staticmethod + def is_carmichael(n): + sympy_deprecation_warning( + """ +is_carmichael is just a wrapper around sympy.ntheory.factor_.is_carmichael so use that +directly instead. + """, + deprecated_since_version="1.13", + active_deprecations_target='deprecated-ntheory-symbolic-functions', + ) + return is_carmichael(n) + + @staticmethod + def find_carmichael_numbers_in_range(x, y): + sympy_deprecation_warning( + """ +find_carmichael_numbers_in_range is just a wrapper around sympy.ntheory.factor_.find_carmichael_numbers_in_range so use that +directly instead. + """, + deprecated_since_version="1.13", + active_deprecations_target='deprecated-ntheory-symbolic-functions', + ) + return find_carmichael_numbers_in_range(x, y) + + @staticmethod + def find_first_n_carmichaels(n): + sympy_deprecation_warning( + """ +find_first_n_carmichaels is just a wrapper around sympy.ntheory.factor_.find_first_n_carmichaels so use that +directly instead. + """, + deprecated_since_version="1.13", + active_deprecations_target='deprecated-ntheory-symbolic-functions', + ) + return find_first_n_carmichaels(n) + + +#----------------------------------------------------------------------------# +# # +# Fibonacci numbers # +# # +#----------------------------------------------------------------------------# + + +class fibonacci(DefinedFunction): + r""" + Fibonacci numbers / Fibonacci polynomials + + The Fibonacci numbers are the integer sequence defined by the + initial terms `F_0 = 0`, `F_1 = 1` and the two-term recurrence + relation `F_n = F_{n-1} + F_{n-2}`. This definition + extended to arbitrary real and complex arguments using + the formula + + .. math :: F_z = \frac{\phi^z - \cos(\pi z) \phi^{-z}}{\sqrt 5} + + The Fibonacci polynomials are defined by `F_1(x) = 1`, + `F_2(x) = x`, and `F_n(x) = x*F_{n-1}(x) + F_{n-2}(x)` for `n > 2`. + For all positive integers `n`, `F_n(1) = F_n`. + + * ``fibonacci(n)`` gives the `n^{th}` Fibonacci number, `F_n` + * ``fibonacci(n, x)`` gives the `n^{th}` Fibonacci polynomial in `x`, `F_n(x)` + + Examples + ======== + + >>> from sympy import fibonacci, Symbol + + >>> [fibonacci(x) for x in range(11)] + [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55] + >>> fibonacci(5, Symbol('t')) + t**4 + 3*t**2 + 1 + + See Also + ======== + + bell, bernoulli, catalan, euler, harmonic, lucas, genocchi, partition, tribonacci + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Fibonacci_number + .. [2] https://mathworld.wolfram.com/FibonacciNumber.html + + """ + + @staticmethod + def _fib(n): + return _ifib(n) + + @staticmethod + @recurrence_memo([None, S.One, _sym]) + def _fibpoly(n, prev): + return (prev[-2] + _sym*prev[-1]).expand() + + @classmethod + def eval(cls, n, sym=None): + if n is S.Infinity: + return S.Infinity + + if n.is_Integer: + if sym is None: + n = int(n) + if n < 0: + return S.NegativeOne**(n + 1) * fibonacci(-n) + else: + return Integer(cls._fib(n)) + else: + if n < 1: + raise ValueError("Fibonacci polynomials are defined " + "only for positive integer indices.") + return cls._fibpoly(n).subs(_sym, sym) + + def _eval_rewrite_as_tractable(self, n, **kwargs): + from sympy.functions import sqrt, cos + return (S.GoldenRatio**n - cos(S.Pi*n)/S.GoldenRatio**n)/sqrt(5) + + def _eval_rewrite_as_sqrt(self, n, **kwargs): + from sympy.functions.elementary.miscellaneous import sqrt + return 2**(-n)*sqrt(5)*((1 + sqrt(5))**n - (-sqrt(5) + 1)**n) / 5 + + def _eval_rewrite_as_GoldenRatio(self,n, **kwargs): + return (S.GoldenRatio**n - 1/(-S.GoldenRatio)**n)/(2*S.GoldenRatio-1) + + +#----------------------------------------------------------------------------# +# # +# Lucas numbers # +# # +#----------------------------------------------------------------------------# + + +class lucas(DefinedFunction): + """ + Lucas numbers + + Lucas numbers satisfy a recurrence relation similar to that of + the Fibonacci sequence, in which each term is the sum of the + preceding two. They are generated by choosing the initial + values `L_0 = 2` and `L_1 = 1`. + + * ``lucas(n)`` gives the `n^{th}` Lucas number + + Examples + ======== + + >>> from sympy import lucas + + >>> [lucas(x) for x in range(11)] + [2, 1, 3, 4, 7, 11, 18, 29, 47, 76, 123] + + See Also + ======== + + bell, bernoulli, catalan, euler, fibonacci, harmonic, genocchi, partition, tribonacci + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Lucas_number + .. [2] https://mathworld.wolfram.com/LucasNumber.html + + """ + + @classmethod + def eval(cls, n): + if n is S.Infinity: + return S.Infinity + + if n.is_Integer: + return fibonacci(n + 1) + fibonacci(n - 1) + + def _eval_rewrite_as_sqrt(self, n, **kwargs): + from sympy.functions.elementary.miscellaneous import sqrt + return 2**(-n)*((1 + sqrt(5))**n + (-sqrt(5) + 1)**n) + + +#----------------------------------------------------------------------------# +# # +# Tribonacci numbers # +# # +#----------------------------------------------------------------------------# + + +class tribonacci(DefinedFunction): + r""" + Tribonacci numbers / Tribonacci polynomials + + The Tribonacci numbers are the integer sequence defined by the + initial terms `T_0 = 0`, `T_1 = 1`, `T_2 = 1` and the three-term + recurrence relation `T_n = T_{n-1} + T_{n-2} + T_{n-3}`. + + The Tribonacci polynomials are defined by `T_0(x) = 0`, `T_1(x) = 1`, + `T_2(x) = x^2`, and `T_n(x) = x^2 T_{n-1}(x) + x T_{n-2}(x) + T_{n-3}(x)` + for `n > 2`. For all positive integers `n`, `T_n(1) = T_n`. + + * ``tribonacci(n)`` gives the `n^{th}` Tribonacci number, `T_n` + * ``tribonacci(n, x)`` gives the `n^{th}` Tribonacci polynomial in `x`, `T_n(x)` + + Examples + ======== + + >>> from sympy import tribonacci, Symbol + + >>> [tribonacci(x) for x in range(11)] + [0, 1, 1, 2, 4, 7, 13, 24, 44, 81, 149] + >>> tribonacci(5, Symbol('t')) + t**8 + 3*t**5 + 3*t**2 + + See Also + ======== + + bell, bernoulli, catalan, euler, fibonacci, harmonic, lucas, genocchi, partition + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Generalizations_of_Fibonacci_numbers#Tribonacci_numbers + .. [2] https://mathworld.wolfram.com/TribonacciNumber.html + .. [3] https://oeis.org/A000073 + + """ + + @staticmethod + @recurrence_memo([S.Zero, S.One, S.One]) + def _trib(n, prev): + return (prev[-3] + prev[-2] + prev[-1]) + + @staticmethod + @recurrence_memo([S.Zero, S.One, _sym**2]) + def _tribpoly(n, prev): + return (prev[-3] + _sym*prev[-2] + _sym**2*prev[-1]).expand() + + @classmethod + def eval(cls, n, sym=None): + if n is S.Infinity: + return S.Infinity + + if n.is_Integer: + n = int(n) + if n < 0: + raise ValueError("Tribonacci polynomials are defined " + "only for non-negative integer indices.") + if sym is None: + return Integer(cls._trib(n)) + else: + return cls._tribpoly(n).subs(_sym, sym) + + def _eval_rewrite_as_sqrt(self, n, **kwargs): + from sympy.functions.elementary.miscellaneous import cbrt, sqrt + w = (-1 + S.ImaginaryUnit * sqrt(3)) / 2 + a = (1 + cbrt(19 + 3*sqrt(33)) + cbrt(19 - 3*sqrt(33))) / 3 + b = (1 + w*cbrt(19 + 3*sqrt(33)) + w**2*cbrt(19 - 3*sqrt(33))) / 3 + c = (1 + w**2*cbrt(19 + 3*sqrt(33)) + w*cbrt(19 - 3*sqrt(33))) / 3 + Tn = (a**(n + 1)/((a - b)*(a - c)) + + b**(n + 1)/((b - a)*(b - c)) + + c**(n + 1)/((c - a)*(c - b))) + return Tn + + def _eval_rewrite_as_TribonacciConstant(self, n, **kwargs): + from sympy.functions.elementary.integers import floor + from sympy.functions.elementary.miscellaneous import cbrt, sqrt + b = cbrt(586 + 102*sqrt(33)) + Tn = 3 * b * S.TribonacciConstant**n / (b**2 - 2*b + 4) + return floor(Tn + S.Half) + + +#----------------------------------------------------------------------------# +# # +# Bernoulli numbers # +# # +#----------------------------------------------------------------------------# + + +class bernoulli(DefinedFunction): + r""" + Bernoulli numbers / Bernoulli polynomials / Bernoulli function + + The Bernoulli numbers are a sequence of rational numbers + defined by `B_0 = 1` and the recursive relation (`n > 0`): + + .. math :: n+1 = \sum_{k=0}^n \binom{n+1}{k} B_k + + They are also commonly defined by their exponential generating + function, which is `\frac{x}{1 - e^{-x}}`. For odd indices > 1, + the Bernoulli numbers are zero. + + The Bernoulli polynomials satisfy the analogous formula: + + .. math :: B_n(x) = \sum_{k=0}^n (-1)^k \binom{n}{k} B_k x^{n-k} + + Bernoulli numbers and Bernoulli polynomials are related as + `B_n(1) = B_n`. + + The generalized Bernoulli function `\operatorname{B}(s, a)` + is defined for any complex `s` and `a`, except where `a` is a + nonpositive integer and `s` is not a nonnegative integer. It is + an entire function of `s` for fixed `a`, related to the Hurwitz + zeta function by + + .. math:: \operatorname{B}(s, a) = \begin{cases} + -s \zeta(1-s, a) & s \ne 0 \\ 1 & s = 0 \end{cases} + + When `s` is a nonnegative integer this function reduces to the + Bernoulli polynomials: `\operatorname{B}(n, x) = B_n(x)`. When + `a` is omitted it is assumed to be 1, yielding the (ordinary) + Bernoulli function which interpolates the Bernoulli numbers and is + related to the Riemann zeta function. + + We compute Bernoulli numbers using Ramanujan's formula: + + .. math :: B_n = \frac{A(n) - S(n)}{\binom{n+3}{n}} + + where: + + .. math :: A(n) = \begin{cases} \frac{n+3}{3} & + n \equiv 0\ \text{or}\ 2 \pmod{6} \\ + -\frac{n+3}{6} & n \equiv 4 \pmod{6} \end{cases} + + and: + + .. math :: S(n) = \sum_{k=1}^{[n/6]} \binom{n+3}{n-6k} B_{n-6k} + + This formula is similar to the sum given in the definition, but + cuts `\frac{2}{3}` of the terms. For Bernoulli polynomials, we use + Appell sequences. + + For `n` a nonnegative integer and `s`, `a`, `x` arbitrary complex numbers, + + * ``bernoulli(n)`` gives the nth Bernoulli number, `B_n` + * ``bernoulli(s)`` gives the Bernoulli function `\operatorname{B}(s)` + * ``bernoulli(n, x)`` gives the nth Bernoulli polynomial in `x`, `B_n(x)` + * ``bernoulli(s, a)`` gives the generalized Bernoulli function + `\operatorname{B}(s, a)` + + .. versionchanged:: 1.12 + ``bernoulli(1)`` gives `+\frac{1}{2}` instead of `-\frac{1}{2}`. + This choice of value confers several theoretical advantages [5]_, + including the extension to complex parameters described above + which this function now implements. The previous behavior, defined + only for nonnegative integers `n`, can be obtained with + ``(-1)**n*bernoulli(n)``. + + Examples + ======== + + >>> from sympy import bernoulli + >>> from sympy.abc import x + >>> [bernoulli(n) for n in range(11)] + [1, 1/2, 1/6, 0, -1/30, 0, 1/42, 0, -1/30, 0, 5/66] + >>> bernoulli(1000001) + 0 + >>> bernoulli(3, x) + x**3 - 3*x**2/2 + x/2 + + See Also + ======== + + andre, bell, catalan, euler, fibonacci, harmonic, lucas, genocchi, + partition, tribonacci, sympy.polys.appellseqs.bernoulli_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Bernoulli_number + .. [2] https://en.wikipedia.org/wiki/Bernoulli_polynomial + .. [3] https://mathworld.wolfram.com/BernoulliNumber.html + .. [4] https://mathworld.wolfram.com/BernoulliPolynomial.html + .. [5] Peter Luschny, "The Bernoulli Manifesto", + https://luschny.de/math/zeta/The-Bernoulli-Manifesto.html + .. [6] Peter Luschny, "An introduction to the Bernoulli function", + https://arxiv.org/abs/2009.06743 + + """ + + args: tuple[Integer] + + # Calculates B_n for positive even n + @staticmethod + def _calc_bernoulli(n): + s = 0 + a = int(binomial(n + 3, n - 6)) + for j in range(1, n//6 + 1): + s += a * bernoulli(n - 6*j) + # Avoid computing each binomial coefficient from scratch + a *= _product(n - 6 - 6*j + 1, n - 6*j) + a //= _product(6*j + 4, 6*j + 9) + if n % 6 == 4: + s = -Rational(n + 3, 6) - s + else: + s = Rational(n + 3, 3) - s + return s / binomial(n + 3, n) + + # We implement a specialized memoization scheme to handle each + # case modulo 6 separately + _cache = {0: S.One, 1: Rational(1, 2), 2: Rational(1, 6), 4: Rational(-1, 30)} + _highest = {0: 0, 1: 1, 2: 2, 4: 4} + + @classmethod + def eval(cls, n, x=None): + if x is S.One: + return cls(n) + elif n.is_zero: + return S.One + elif n.is_integer is False or n.is_nonnegative is False: + if x is not None and x.is_Integer and x.is_nonpositive: + return S.NaN + return + # Bernoulli numbers + elif x is None: + if n is S.One: + return S.Half + elif n.is_odd and (n-1).is_positive: + return S.Zero + elif n.is_Number: + n = int(n) + # Use mpmath for enormous Bernoulli numbers + if n > 500: + p, q = mp.bernfrac(n) + return Rational(int(p), int(q)) + case = n % 6 + highest_cached = cls._highest[case] + if n <= highest_cached: + return cls._cache[n] + # To avoid excessive recursion when, say, bernoulli(1000) is + # requested, calculate and cache the entire sequence ... B_988, + # B_994, B_1000 in increasing order + for i in range(highest_cached + 6, n + 6, 6): + b = cls._calc_bernoulli(i) + cls._cache[i] = b + cls._highest[case] = i + return b + # Bernoulli polynomials + elif n.is_Number: + return bernoulli_poly(n, x) + + def _eval_rewrite_as_zeta(self, n, x=1, **kwargs): + from sympy.functions.special.zeta_functions import zeta + return Piecewise((1, Eq(n, 0)), (-n * zeta(1-n, x), True)) + + def _eval_evalf(self, prec): + if not all(x.is_number for x in self.args): + return + n = self.args[0]._to_mpmath(prec) + x = (self.args[1] if len(self.args) > 1 else S.One)._to_mpmath(prec) + with workprec(prec): + if n == 0: + res = mp.mpf(1) + elif n == 1: + res = x - mp.mpf(0.5) + elif mp.isint(n) and n >= 0: + res = mp.bernoulli(n) if x == 1 else mp.bernpoly(n, x) + else: + res = -n * mp.zeta(1-n, x) + return Expr._from_mpmath(res, prec) + + +#----------------------------------------------------------------------------# +# # +# Bell numbers # +# # +#----------------------------------------------------------------------------# + + +class bell(DefinedFunction): + r""" + Bell numbers / Bell polynomials + + The Bell numbers satisfy `B_0 = 1` and + + .. math:: B_n = \sum_{k=0}^{n-1} \binom{n-1}{k} B_k. + + They are also given by: + + .. math:: B_n = \frac{1}{e} \sum_{k=0}^{\infty} \frac{k^n}{k!}. + + The Bell polynomials are given by `B_0(x) = 1` and + + .. math:: B_n(x) = x \sum_{k=1}^{n-1} \binom{n-1}{k-1} B_{k-1}(x). + + The second kind of Bell polynomials (are sometimes called "partial" Bell + polynomials or incomplete Bell polynomials) are defined as + + .. math:: B_{n,k}(x_1, x_2,\dotsc x_{n-k+1}) = + \sum_{j_1+j_2+j_2+\dotsb=k \atop j_1+2j_2+3j_2+\dotsb=n} + \frac{n!}{j_1!j_2!\dotsb j_{n-k+1}!} + \left(\frac{x_1}{1!} \right)^{j_1} + \left(\frac{x_2}{2!} \right)^{j_2} \dotsb + \left(\frac{x_{n-k+1}}{(n-k+1)!} \right) ^{j_{n-k+1}}. + + * ``bell(n)`` gives the `n^{th}` Bell number, `B_n`. + * ``bell(n, x)`` gives the `n^{th}` Bell polynomial, `B_n(x)`. + * ``bell(n, k, (x1, x2, ...))`` gives Bell polynomials of the second kind, + `B_{n,k}(x_1, x_2, \dotsc, x_{n-k+1})`. + + Notes + ===== + + Not to be confused with Bernoulli numbers and Bernoulli polynomials, + which use the same notation. + + Examples + ======== + + >>> from sympy import bell, Symbol, symbols + + >>> [bell(n) for n in range(11)] + [1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147, 115975] + >>> bell(30) + 846749014511809332450147 + >>> bell(4, Symbol('t')) + t**4 + 6*t**3 + 7*t**2 + t + >>> bell(6, 2, symbols('x:6')[1:]) + 6*x1*x5 + 15*x2*x4 + 10*x3**2 + + See Also + ======== + + bernoulli, catalan, euler, fibonacci, harmonic, lucas, genocchi, partition, tribonacci + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Bell_number + .. [2] https://mathworld.wolfram.com/BellNumber.html + .. [3] https://mathworld.wolfram.com/BellPolynomial.html + + """ + + @staticmethod + @recurrence_memo([1, 1]) + def _bell(n, prev): + s = 1 + a = 1 + for k in range(1, n): + a = a * (n - k) // k + s += a * prev[k] + return s + + @staticmethod + @recurrence_memo([S.One, _sym]) + def _bell_poly(n, prev): + s = 1 + a = 1 + for k in range(2, n + 1): + a = a * (n - k + 1) // (k - 1) + s += a * prev[k - 1] + return expand_mul(_sym * s) + + @staticmethod + def _bell_incomplete_poly(n, k, symbols): + r""" + The second kind of Bell polynomials (incomplete Bell polynomials). + + Calculated by recurrence formula: + + .. math:: B_{n,k}(x_1, x_2, \dotsc, x_{n-k+1}) = + \sum_{m=1}^{n-k+1} + \x_m \binom{n-1}{m-1} B_{n-m,k-1}(x_1, x_2, \dotsc, x_{n-m-k}) + + where + `B_{0,0} = 1;` + `B_{n,0} = 0; for n \ge 1` + `B_{0,k} = 0; for k \ge 1` + + """ + if (n == 0) and (k == 0): + return S.One + elif (n == 0) or (k == 0): + return S.Zero + s = S.Zero + a = S.One + for m in range(1, n - k + 2): + s += a * bell._bell_incomplete_poly( + n - m, k - 1, symbols) * symbols[m - 1] + a = a * (n - m) / m + return expand_mul(s) + + @classmethod + def eval(cls, n, k_sym=None, symbols=None): + if n is S.Infinity: + if k_sym is None: + return S.Infinity + else: + raise ValueError("Bell polynomial is not defined") + + if n.is_negative or n.is_integer is False: + raise ValueError("a non-negative integer expected") + + if n.is_Integer and n.is_nonnegative: + if k_sym is None: + return Integer(cls._bell(int(n))) + elif symbols is None: + return cls._bell_poly(int(n)).subs(_sym, k_sym) + else: + r = cls._bell_incomplete_poly(int(n), int(k_sym), symbols) + return r + + def _eval_rewrite_as_Sum(self, n, k_sym=None, symbols=None, **kwargs): + from sympy.concrete.summations import Sum + if (k_sym is not None) or (symbols is not None): + return self + + # Dobinski's formula + if not n.is_nonnegative: + return self + k = Dummy('k', integer=True, nonnegative=True) + return 1 / E * Sum(k**n / factorial(k), (k, 0, S.Infinity)) + + +#----------------------------------------------------------------------------# +# # +# Harmonic numbers # +# # +#----------------------------------------------------------------------------# + + +class harmonic(DefinedFunction): + r""" + Harmonic numbers + + The nth harmonic number is given by `\operatorname{H}_{n} = + 1 + \frac{1}{2} + \frac{1}{3} + \ldots + \frac{1}{n}`. + + More generally: + + .. math:: \operatorname{H}_{n,m} = \sum_{k=1}^{n} \frac{1}{k^m} + + As `n \rightarrow \infty`, `\operatorname{H}_{n,m} \rightarrow \zeta(m)`, + the Riemann zeta function. + + * ``harmonic(n)`` gives the nth harmonic number, `\operatorname{H}_n` + + * ``harmonic(n, m)`` gives the nth generalized harmonic number + of order `m`, `\operatorname{H}_{n,m}`, where + ``harmonic(n) == harmonic(n, 1)`` + + This function can be extended to complex `n` and `m` where `n` is not a + negative integer or `m` is a nonpositive integer as + + .. math:: \operatorname{H}_{n,m} = \begin{cases} \zeta(m) - \zeta(m, n+1) + & m \ne 1 \\ \psi(n+1) + \gamma & m = 1 \end{cases} + + Examples + ======== + + >>> from sympy import harmonic, oo + + >>> [harmonic(n) for n in range(6)] + [0, 1, 3/2, 11/6, 25/12, 137/60] + >>> [harmonic(n, 2) for n in range(6)] + [0, 1, 5/4, 49/36, 205/144, 5269/3600] + >>> harmonic(oo, 2) + pi**2/6 + + >>> from sympy import Symbol, Sum + >>> n = Symbol("n") + + >>> harmonic(n).rewrite(Sum) + Sum(1/_k, (_k, 1, n)) + + We can evaluate harmonic numbers for all integral and positive + rational arguments: + + >>> from sympy import S, expand_func, simplify + >>> harmonic(8) + 761/280 + >>> harmonic(11) + 83711/27720 + + >>> H = harmonic(1/S(3)) + >>> H + harmonic(1/3) + >>> He = expand_func(H) + >>> He + -log(6) - sqrt(3)*pi/6 + 2*Sum(log(sin(_k*pi/3))*cos(2*_k*pi/3), (_k, 1, 1)) + + 3*Sum(1/(3*_k + 1), (_k, 0, 0)) + >>> He.doit() + -log(6) - sqrt(3)*pi/6 - log(sqrt(3)/2) + 3 + >>> H = harmonic(25/S(7)) + >>> He = simplify(expand_func(H).doit()) + >>> He + log(sin(2*pi/7)**(2*cos(16*pi/7))/(14*sin(pi/7)**(2*cos(pi/7))*cos(pi/14)**(2*sin(pi/14)))) + pi*tan(pi/14)/2 + 30247/9900 + >>> He.n(40) + 1.983697455232980674869851942390639915940 + >>> harmonic(25/S(7)).n(40) + 1.983697455232980674869851942390639915940 + + We can rewrite harmonic numbers in terms of polygamma functions: + + >>> from sympy import digamma, polygamma + >>> m = Symbol("m", integer=True, positive=True) + + >>> harmonic(n).rewrite(digamma) + polygamma(0, n + 1) + EulerGamma + + >>> harmonic(n).rewrite(polygamma) + polygamma(0, n + 1) + EulerGamma + + >>> harmonic(n,3).rewrite(polygamma) + polygamma(2, n + 1)/2 + zeta(3) + + >>> simplify(harmonic(n,m).rewrite(polygamma)) + Piecewise((polygamma(0, n + 1) + EulerGamma, Eq(m, 1)), + (-(-1)**m*polygamma(m - 1, n + 1)/factorial(m - 1) + zeta(m), True)) + + Integer offsets in the argument can be pulled out: + + >>> from sympy import expand_func + + >>> expand_func(harmonic(n+4)) + harmonic(n) + 1/(n + 4) + 1/(n + 3) + 1/(n + 2) + 1/(n + 1) + + >>> expand_func(harmonic(n-4)) + harmonic(n) - 1/(n - 1) - 1/(n - 2) - 1/(n - 3) - 1/n + + Some limits can be computed as well: + + >>> from sympy import limit, oo + + >>> limit(harmonic(n), n, oo) + oo + + >>> limit(harmonic(n, 2), n, oo) + pi**2/6 + + >>> limit(harmonic(n, 3), n, oo) + zeta(3) + + For `m > 1`, `H_{n,m}` tends to `\zeta(m)` in the limit of infinite `n`: + + >>> m = Symbol("m", positive=True) + >>> limit(harmonic(n, m+1), n, oo) + zeta(m + 1) + + See Also + ======== + + bell, bernoulli, catalan, euler, fibonacci, lucas, genocchi, partition, tribonacci + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Harmonic_number + .. [2] https://functions.wolfram.com/GammaBetaErf/HarmonicNumber/ + .. [3] https://functions.wolfram.com/GammaBetaErf/HarmonicNumber2/ + + """ + + # This prevents redundant recalculations and speeds up harmonic number computations. + harmonic_cache: dict[Integer, Callable[[int], Rational]] = {} + + @classmethod + def eval(cls, n, m=None): + from sympy.functions.special.zeta_functions import zeta + if m is S.One: + return cls(n) + if m is None: + m = S.One + if n.is_zero: + return S.Zero + elif m.is_zero: + return n + elif n is S.Infinity: + if m.is_negative: + return S.NaN + elif is_le(m, S.One): + return S.Infinity + elif is_gt(m, S.One): + return zeta(m) + elif m.is_Integer and m.is_nonpositive: + return (bernoulli(1-m, n+1) - bernoulli(1-m)) / (1-m) + elif n.is_Integer: + if n.is_negative and (m.is_integer is False or m.is_nonpositive is False): + return S.ComplexInfinity if m is S.One else S.NaN + if n.is_nonnegative: + if m.is_Integer: + if m not in cls.harmonic_cache: + @recurrence_memo([0]) + def f(n, prev): + return prev[-1] + S.One / n**m + cls.harmonic_cache[m] = f + return cls.harmonic_cache[m](int(n)) + return Add(*(k**(-m) for k in range(1, int(n) + 1))) + + def _eval_rewrite_as_polygamma(self, n, m=S.One, **kwargs): + from sympy.functions.special.gamma_functions import gamma, polygamma + if m.is_integer and m.is_positive: + return Piecewise((polygamma(0, n+1) + S.EulerGamma, Eq(m, 1)), + (S.NegativeOne**m * (polygamma(m-1, 1) - polygamma(m-1, n+1)) / + gamma(m), True)) + + def _eval_rewrite_as_digamma(self, n, m=1, **kwargs): + from sympy.functions.special.gamma_functions import polygamma + return self.rewrite(polygamma) + + def _eval_rewrite_as_trigamma(self, n, m=1, **kwargs): + from sympy.functions.special.gamma_functions import polygamma + return self.rewrite(polygamma) + + def _eval_rewrite_as_Sum(self, n, m=None, **kwargs): + from sympy.concrete.summations import Sum + k = Dummy("k", integer=True) + if m is None: + m = S.One + return Sum(k**(-m), (k, 1, n)) + + def _eval_rewrite_as_zeta(self, n, m=S.One, **kwargs): + from sympy.functions.special.zeta_functions import zeta + from sympy.functions.special.gamma_functions import digamma + return Piecewise((digamma(n + 1) + S.EulerGamma, Eq(m, 1)), + (zeta(m) - zeta(m, n+1), True)) + + def _eval_expand_func(self, **hints): + from sympy.concrete.summations import Sum + n = self.args[0] + m = self.args[1] if len(self.args) == 2 else 1 + + if m == S.One: + if n.is_Add: + off = n.args[0] + nnew = n - off + if off.is_Integer and off.is_positive: + result = [S.One/(nnew + i) for i in range(off, 0, -1)] + [harmonic(nnew)] + return Add(*result) + elif off.is_Integer and off.is_negative: + result = [-S.One/(nnew + i) for i in range(0, off, -1)] + [harmonic(nnew)] + return Add(*result) + + if n.is_Rational: + # Expansions for harmonic numbers at general rational arguments (u + p/q) + # Split n as u + p/q with p < q + p, q = n.as_numer_denom() + u = p // q + p = p - u * q + if u.is_nonnegative and p.is_positive and q.is_positive and p < q: + from sympy.functions.elementary.exponential import log + from sympy.functions.elementary.integers import floor + from sympy.functions.elementary.trigonometric import sin, cos, cot + k = Dummy("k") + t1 = q * Sum(1 / (q * k + p), (k, 0, u)) + t2 = 2 * Sum(cos((2 * pi * p * k) / S(q)) * + log(sin((pi * k) / S(q))), + (k, 1, floor((q - 1) / S(2)))) + t3 = (pi / 2) * cot((pi * p) / q) + log(2 * q) + return t1 + t2 - t3 + + return self + + def _eval_rewrite_as_tractable(self, n, m=1, limitvar=None, **kwargs): + from sympy.functions.special.zeta_functions import zeta + from sympy.functions.special.gamma_functions import polygamma + pg = self.rewrite(polygamma) + if not isinstance(pg, harmonic): + return pg.rewrite("tractable", deep=True) + arg = m - S.One + if arg.is_nonzero: + return (zeta(m) - zeta(m, n+1)).rewrite("tractable", deep=True) + + def _eval_evalf(self, prec): + if not all(x.is_number for x in self.args): + return + n = self.args[0]._to_mpmath(prec) + m = (self.args[1] if len(self.args) > 1 else S.One)._to_mpmath(prec) + if mp.isint(n) and n < 0: + return S.NaN + with workprec(prec): + if m == 1: + res = mp.harmonic(n) + else: + res = mp.zeta(m) - mp.zeta(m, n+1) + return Expr._from_mpmath(res, prec) + + def fdiff(self, argindex=1): + from sympy.functions.special.zeta_functions import zeta + if len(self.args) == 2: + n, m = self.args + else: + n, m = self.args + (1,) + if argindex == 1: + return m * zeta(m+1, n+1) + else: + raise ArgumentIndexError + + +#----------------------------------------------------------------------------# +# # +# Euler numbers # +# # +#----------------------------------------------------------------------------# + + +class euler(DefinedFunction): + r""" + Euler numbers / Euler polynomials / Euler function + + The Euler numbers are given by: + + .. math:: E_{2n} = I \sum_{k=1}^{2n+1} \sum_{j=0}^k \binom{k}{j} + \frac{(-1)^j (k-2j)^{2n+1}}{2^k I^k k} + + .. math:: E_{2n+1} = 0 + + Euler numbers and Euler polynomials are related by + + .. math:: E_n = 2^n E_n\left(\frac{1}{2}\right). + + We compute symbolic Euler polynomials using Appell sequences, + but numerical evaluation of the Euler polynomial is computed + more efficiently (and more accurately) using the mpmath library. + + The Euler polynomials are special cases of the generalized Euler function, + related to the Genocchi function as + + .. math:: \operatorname{E}(s, a) = -\frac{\operatorname{G}(s+1, a)}{s+1} + + with the limit of `\psi\left(\frac{a+1}{2}\right) - \psi\left(\frac{a}{2}\right)` + being taken when `s = -1`. The (ordinary) Euler function interpolating + the Euler numbers is then obtained as + `\operatorname{E}(s) = 2^s \operatorname{E}\left(s, \frac{1}{2}\right)`. + + * ``euler(n)`` gives the nth Euler number `E_n`. + * ``euler(s)`` gives the Euler function `\operatorname{E}(s)`. + * ``euler(n, x)`` gives the nth Euler polynomial `E_n(x)`. + * ``euler(s, a)`` gives the generalized Euler function `\operatorname{E}(s, a)`. + + Examples + ======== + + >>> from sympy import euler, Symbol, S + >>> [euler(n) for n in range(10)] + [1, 0, -1, 0, 5, 0, -61, 0, 1385, 0] + >>> [2**n*euler(n,1) for n in range(10)] + [1, 1, 0, -2, 0, 16, 0, -272, 0, 7936] + >>> n = Symbol("n") + >>> euler(n + 2*n) + euler(3*n) + + >>> x = Symbol("x") + >>> euler(n, x) + euler(n, x) + + >>> euler(0, x) + 1 + >>> euler(1, x) + x - 1/2 + >>> euler(2, x) + x**2 - x + >>> euler(3, x) + x**3 - 3*x**2/2 + 1/4 + >>> euler(4, x) + x**4 - 2*x**3 + x + + >>> euler(12, S.Half) + 2702765/4096 + >>> euler(12) + 2702765 + + See Also + ======== + + andre, bell, bernoulli, catalan, fibonacci, harmonic, lucas, genocchi, + partition, tribonacci, sympy.polys.appellseqs.euler_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Euler_numbers + .. [2] https://mathworld.wolfram.com/EulerNumber.html + .. [3] https://en.wikipedia.org/wiki/Alternating_permutation + .. [4] https://mathworld.wolfram.com/AlternatingPermutation.html + + """ + + @classmethod + def eval(cls, n, x=None): + if n.is_zero: + return S.One + elif n is S.NegativeOne: + if x is None: + return S.Pi/2 + from sympy.functions.special.gamma_functions import digamma + return digamma((x+1)/2) - digamma(x/2) + elif n.is_integer is False or n.is_nonnegative is False: + return + # Euler numbers + elif x is None: + if n.is_odd and n.is_positive: + return S.Zero + elif n.is_Number: + from mpmath import mp + n = n._to_mpmath(mp.prec) + res = mp.eulernum(n, exact=True) + return Integer(res) + # Euler polynomials + elif n.is_Number: + from sympy.core.evalf import pure_complex + n = int(n) + reim = pure_complex(x, or_real=True) + if reim and all(a.is_Float or a.is_Integer for a in reim) \ + and any(a.is_Float for a in reim): + from mpmath import mp + prec = min([a._prec for a in reim if a.is_Float]) + with workprec(prec): + res = mp.eulerpoly(n, x) + return Expr._from_mpmath(res, prec) + return euler_poly(n, x) + + def _eval_rewrite_as_Sum(self, n, x=None, **kwargs): + from sympy.concrete.summations import Sum + if x is None and n.is_even: + k = Dummy("k", integer=True) + j = Dummy("j", integer=True) + n = n / 2 + Em = (S.ImaginaryUnit * Sum(Sum(binomial(k, j) * (S.NegativeOne**j * + (k - 2*j)**(2*n + 1)) / + (2**k*S.ImaginaryUnit**k * k), (j, 0, k)), (k, 1, 2*n + 1))) + return Em + if x: + k = Dummy("k", integer=True) + return Sum(binomial(n, k)*euler(k)/2**k*(x - S.Half)**(n - k), (k, 0, n)) + + def _eval_rewrite_as_genocchi(self, n, x=None, **kwargs): + if x is None: + return Piecewise((S.Pi/2, Eq(n, -1)), + (-2**n * genocchi(n+1, S.Half) / (n+1), True)) + from sympy.functions.special.gamma_functions import digamma + return Piecewise((digamma((x+1)/2) - digamma(x/2), Eq(n, -1)), + (-genocchi(n+1, x) / (n+1), True)) + + def _eval_evalf(self, prec): + if not all(i.is_number for i in self.args): + return + from mpmath import mp + m, x = (self.args[0], None) if len(self.args) == 1 else self.args + m = m._to_mpmath(prec) + if x is not None: + x = x._to_mpmath(prec) + with workprec(prec): + if mp.isint(m) and m >= 0: + res = mp.eulernum(m) if x is None else mp.eulerpoly(m, x) + else: + if m == -1: + res = mp.pi if x is None else mp.digamma((x+1)/2) - mp.digamma(x/2) + else: + y = 0.5 if x is None else x + res = 2 * (mp.zeta(-m, y) - 2**(m+1) * mp.zeta(-m, (y+1)/2)) + if x is None: + res *= 2**m + return Expr._from_mpmath(res, prec) + + +#----------------------------------------------------------------------------# +# # +# Catalan numbers # +# # +#----------------------------------------------------------------------------# + + +class catalan(DefinedFunction): + r""" + Catalan numbers + + The `n^{th}` catalan number is given by: + + .. math :: C_n = \frac{1}{n+1} \binom{2n}{n} + + * ``catalan(n)`` gives the `n^{th}` Catalan number, `C_n` + + Examples + ======== + + >>> from sympy import (Symbol, binomial, gamma, hyper, + ... catalan, diff, combsimp, Rational, I) + + >>> [catalan(i) for i in range(1,10)] + [1, 2, 5, 14, 42, 132, 429, 1430, 4862] + + >>> n = Symbol("n", integer=True) + + >>> catalan(n) + catalan(n) + + Catalan numbers can be transformed into several other, identical + expressions involving other mathematical functions + + >>> catalan(n).rewrite(binomial) + binomial(2*n, n)/(n + 1) + + >>> catalan(n).rewrite(gamma) + 4**n*gamma(n + 1/2)/(sqrt(pi)*gamma(n + 2)) + + >>> catalan(n).rewrite(hyper) + hyper((-n, 1 - n), (2,), 1) + + For some non-integer values of n we can get closed form + expressions by rewriting in terms of gamma functions: + + >>> catalan(Rational(1, 2)).rewrite(gamma) + 8/(3*pi) + + We can differentiate the Catalan numbers C(n) interpreted as a + continuous real function in n: + + >>> diff(catalan(n), n) + (polygamma(0, n + 1/2) - polygamma(0, n + 2) + log(4))*catalan(n) + + As a more advanced example consider the following ratio + between consecutive numbers: + + >>> combsimp((catalan(n + 1)/catalan(n)).rewrite(binomial)) + 2*(2*n + 1)/(n + 2) + + The Catalan numbers can be generalized to complex numbers: + + >>> catalan(I).rewrite(gamma) + 4**I*gamma(1/2 + I)/(sqrt(pi)*gamma(2 + I)) + + and evaluated with arbitrary precision: + + >>> catalan(I).evalf(20) + 0.39764993382373624267 - 0.020884341620842555705*I + + See Also + ======== + + andre, bell, bernoulli, euler, fibonacci, harmonic, lucas, genocchi, + partition, tribonacci, sympy.functions.combinatorial.factorials.binomial + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Catalan_number + .. [2] https://mathworld.wolfram.com/CatalanNumber.html + .. [3] https://functions.wolfram.com/GammaBetaErf/CatalanNumber/ + .. [4] http://geometer.org/mathcircles/catalan.pdf + + """ + + @classmethod + def eval(cls, n): + from sympy.functions.special.gamma_functions import gamma + if (n.is_Integer and n.is_nonnegative) or \ + (n.is_noninteger and n.is_negative): + return 4**n*gamma(n + S.Half)/(gamma(S.Half)*gamma(n + 2)) + + if (n.is_integer and n.is_negative): + if (n + 1).is_negative: + return S.Zero + if (n + 1).is_zero: + return Rational(-1, 2) + + def fdiff(self, argindex=1): + from sympy.functions.elementary.exponential import log + from sympy.functions.special.gamma_functions import polygamma + n = self.args[0] + return catalan(n)*(polygamma(0, n + S.Half) - polygamma(0, n + 2) + log(4)) + + def _eval_rewrite_as_binomial(self, n, **kwargs): + return binomial(2*n, n)/(n + 1) + + def _eval_rewrite_as_factorial(self, n, **kwargs): + return factorial(2*n) / (factorial(n+1) * factorial(n)) + + def _eval_rewrite_as_gamma(self, n, piecewise=True, **kwargs): + from sympy.functions.special.gamma_functions import gamma + # The gamma function allows to generalize Catalan numbers to complex n + return 4**n*gamma(n + S.Half)/(gamma(S.Half)*gamma(n + 2)) + + def _eval_rewrite_as_hyper(self, n, **kwargs): + from sympy.functions.special.hyper import hyper + return hyper([1 - n, -n], [2], 1) + + def _eval_rewrite_as_Product(self, n, **kwargs): + from sympy.concrete.products import Product + if not (n.is_integer and n.is_nonnegative): + return self + k = Dummy('k', integer=True, positive=True) + return Product((n + k) / k, (k, 2, n)) + + def _eval_is_integer(self): + if self.args[0].is_integer and self.args[0].is_nonnegative: + return True + + def _eval_is_positive(self): + if self.args[0].is_nonnegative: + return True + + def _eval_is_composite(self): + if self.args[0].is_integer and (self.args[0] - 3).is_positive: + return True + + def _eval_evalf(self, prec): + from sympy.functions.special.gamma_functions import gamma + if self.args[0].is_number: + return self.rewrite(gamma)._eval_evalf(prec) + + +#----------------------------------------------------------------------------# +# # +# Genocchi numbers # +# # +#----------------------------------------------------------------------------# + + +class genocchi(DefinedFunction): + r""" + Genocchi numbers / Genocchi polynomials / Genocchi function + + The Genocchi numbers are a sequence of integers `G_n` that satisfy the + relation: + + .. math:: \frac{-2t}{1 + e^{-t}} = \sum_{n=0}^\infty \frac{G_n t^n}{n!} + + They are related to the Bernoulli numbers by + + .. math:: G_n = 2 (1 - 2^n) B_n + + and generalize like the Bernoulli numbers to the Genocchi polynomials and + function as + + .. math:: \operatorname{G}(s, a) = 2 \left(\operatorname{B}(s, a) - + 2^s \operatorname{B}\left(s, \frac{a+1}{2}\right)\right) + + .. versionchanged:: 1.12 + ``genocchi(1)`` gives `-1` instead of `1`. + + Examples + ======== + + >>> from sympy import genocchi, Symbol + >>> [genocchi(n) for n in range(9)] + [0, -1, -1, 0, 1, 0, -3, 0, 17] + >>> n = Symbol('n', integer=True, positive=True) + >>> genocchi(2*n + 1) + 0 + >>> x = Symbol('x') + >>> genocchi(4, x) + -4*x**3 + 6*x**2 - 1 + + See Also + ======== + + bell, bernoulli, catalan, euler, fibonacci, harmonic, lucas, partition, tribonacci + sympy.polys.appellseqs.genocchi_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Genocchi_number + .. [2] https://mathworld.wolfram.com/GenocchiNumber.html + .. [3] Peter Luschny, "An introduction to the Bernoulli function", + https://arxiv.org/abs/2009.06743 + + """ + + @classmethod + def eval(cls, n, x=None): + if x is S.One: + return cls(n) + elif n.is_integer is False or n.is_nonnegative is False: + return + # Genocchi numbers + elif x is None: + if n.is_odd and (n-1).is_positive: + return S.Zero + elif n.is_Number: + return 2 * (1-S(2)**n) * bernoulli(n) + # Genocchi polynomials + elif n.is_Number: + return genocchi_poly(n, x) + + def _eval_rewrite_as_bernoulli(self, n, x=1, **kwargs): + if x == 1 and n.is_integer and n.is_nonnegative: + return 2 * (1-S(2)**n) * bernoulli(n) + return 2 * (bernoulli(n, x) - 2**n * bernoulli(n, (x+1) / 2)) + + def _eval_rewrite_as_dirichlet_eta(self, n, x=1, **kwargs): + from sympy.functions.special.zeta_functions import dirichlet_eta + return -2*n * dirichlet_eta(1-n, x) + + def _eval_is_integer(self): + if len(self.args) > 1 and self.args[1] != 1: + return + n = self.args[0] + if n.is_integer and n.is_nonnegative: + return True + + def _eval_is_negative(self): + if len(self.args) > 1 and self.args[1] != 1: + return + n = self.args[0] + if n.is_integer and n.is_nonnegative: + if n.is_odd: + return fuzzy_not((n-1).is_positive) + return (n/2).is_odd + + def _eval_is_positive(self): + if len(self.args) > 1 and self.args[1] != 1: + return + n = self.args[0] + if n.is_integer and n.is_nonnegative: + if n.is_zero or n.is_odd: + return False + return (n/2).is_even + + def _eval_is_even(self): + if len(self.args) > 1 and self.args[1] != 1: + return + n = self.args[0] + if n.is_integer and n.is_nonnegative: + if n.is_even: + return n.is_zero + return (n-1).is_positive + + def _eval_is_odd(self): + if len(self.args) > 1 and self.args[1] != 1: + return + n = self.args[0] + if n.is_integer and n.is_nonnegative: + if n.is_even: + return fuzzy_not(n.is_zero) + return fuzzy_not((n-1).is_positive) + + def _eval_is_prime(self): + if len(self.args) > 1 and self.args[1] != 1: + return + n = self.args[0] + # only G_6 = -3 and G_8 = 17 are prime, + # but SymPy does not consider negatives as prime + # so only n=8 is tested + return (n-8).is_zero + + def _eval_evalf(self, prec): + if all(i.is_number for i in self.args): + return self.rewrite(bernoulli)._eval_evalf(prec) + + +#----------------------------------------------------------------------------# +# # +# Andre numbers # +# # +#----------------------------------------------------------------------------# + + +class andre(DefinedFunction): + r""" + Andre numbers / Andre function + + The Andre number `\mathcal{A}_n` is Luschny's name for half the number of + *alternating permutations* on `n` elements, where a permutation is alternating + if adjacent elements alternately compare "greater" and "smaller" going from + left to right. For example, `2 < 3 > 1 < 4` is an alternating permutation. + + This sequence is A000111 in the OEIS, which assigns the names *up/down numbers* + and *Euler zigzag numbers*. It satisfies a recurrence relation similar to that + for the Catalan numbers, with `\mathcal{A}_0 = 1` and + + .. math:: 2 \mathcal{A}_{n+1} = \sum_{k=0}^n \binom{n}{k} \mathcal{A}_k \mathcal{A}_{n-k} + + The Bernoulli and Euler numbers are signed transformations of the odd- and + even-indexed elements of this sequence respectively: + + .. math :: \operatorname{B}_{2k} = \frac{2k \mathcal{A}_{2k-1}}{(-4)^k - (-16)^k} + + .. math :: \operatorname{E}_{2k} = (-1)^k \mathcal{A}_{2k} + + Like the Bernoulli and Euler numbers, the Andre numbers are interpolated by the + entire Andre function: + + .. math :: \mathcal{A}(s) = (-i)^{s+1} \operatorname{Li}_{-s}(i) + + i^{s+1} \operatorname{Li}_{-s}(-i) = \\ \frac{2 \Gamma(s+1)}{(2\pi)^{s+1}} + (\zeta(s+1, 1/4) - \zeta(s+1, 3/4) \cos{\pi s}) + + Examples + ======== + + >>> from sympy import andre, euler, bernoulli + >>> [andre(n) for n in range(11)] + [1, 1, 1, 2, 5, 16, 61, 272, 1385, 7936, 50521] + >>> [(-1)**k * andre(2*k) for k in range(7)] + [1, -1, 5, -61, 1385, -50521, 2702765] + >>> [euler(2*k) for k in range(7)] + [1, -1, 5, -61, 1385, -50521, 2702765] + >>> [andre(2*k-1) * (2*k) / ((-4)**k - (-16)**k) for k in range(1, 8)] + [1/6, -1/30, 1/42, -1/30, 5/66, -691/2730, 7/6] + >>> [bernoulli(2*k) for k in range(1, 8)] + [1/6, -1/30, 1/42, -1/30, 5/66, -691/2730, 7/6] + + See Also + ======== + + bernoulli, catalan, euler, sympy.polys.appellseqs.andre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Alternating_permutation + .. [2] https://mathworld.wolfram.com/EulerZigzagNumber.html + .. [3] Peter Luschny, "An introduction to the Bernoulli function", + https://arxiv.org/abs/2009.06743 + """ + + @classmethod + def eval(cls, n): + if n is S.NaN: + return S.NaN + elif n is S.Infinity: + return S.Infinity + if n.is_zero: + return S.One + elif n == -1: + return -log(2) + elif n == -2: + return -2*S.Catalan + elif n.is_Integer: + if n.is_nonnegative and n.is_even: + return abs(euler(n)) + elif n.is_odd: + from sympy.functions.special.zeta_functions import zeta + m = -n-1 + return I**m * Rational(1-2**m, 4**m) * zeta(-n) + + def _eval_rewrite_as_zeta(self, s, **kwargs): + from sympy.functions.elementary.trigonometric import cos + from sympy.functions.special.gamma_functions import gamma + from sympy.functions.special.zeta_functions import zeta + return 2 * gamma(s+1) / (2*pi)**(s+1) * \ + (zeta(s+1, S.One/4) - cos(pi*s) * zeta(s+1, S(3)/4)) + + def _eval_rewrite_as_polylog(self, s, **kwargs): + from sympy.functions.special.zeta_functions import polylog + return (-I)**(s+1) * polylog(-s, I) + I**(s+1) * polylog(-s, -I) + + def _eval_is_integer(self): + n = self.args[0] + if n.is_integer and n.is_nonnegative: + return True + + def _eval_is_positive(self): + if self.args[0].is_nonnegative: + return True + + def _eval_evalf(self, prec): + if not self.args[0].is_number: + return + s = self.args[0]._to_mpmath(prec+12) + with workprec(prec+12): + sp, cp = mp.sinpi(s/2), mp.cospi(s/2) + res = 2*mp.dirichlet(-s, (-sp, cp, sp, -cp)) + return Expr._from_mpmath(res, prec) + + +#----------------------------------------------------------------------------# +# # +# Partition numbers # +# # +#----------------------------------------------------------------------------# + +class partition(DefinedFunction): + r""" + Partition numbers + + The Partition numbers are a sequence of integers `p_n` that represent the + number of distinct ways of representing `n` as a sum of natural numbers + (with order irrelevant). The generating function for `p_n` is given by: + + .. math:: \sum_{n=0}^\infty p_n x^n = \prod_{k=1}^\infty (1 - x^k)^{-1} + + Examples + ======== + + >>> from sympy import partition, Symbol + >>> [partition(n) for n in range(9)] + [1, 1, 2, 3, 5, 7, 11, 15, 22] + >>> n = Symbol('n', integer=True, negative=True) + >>> partition(n) + 0 + + See Also + ======== + + bell, bernoulli, catalan, euler, fibonacci, harmonic, lucas, genocchi, tribonacci + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Partition_(number_theory%29 + .. [2] https://en.wikipedia.org/wiki/Pentagonal_number_theorem + + """ + is_integer = True + is_nonnegative = True + + @classmethod + def eval(cls, n): + if n.is_integer is False: + raise TypeError("n should be an integer") + if n.is_negative is True: + return S.Zero + if n.is_zero is True or n is S.One: + return S.One + if n.is_Integer is True: + return S(_partition(as_int(n))) + + def _eval_is_positive(self): + if self.args[0].is_nonnegative is True: + return True + + def _eval_Mod(self, q): + # Ramanujan's congruences + n = self.args[0] + for p, rem in [(5, 4), (7, 5), (11, 6)]: + if q == p and n % q == rem: + return S.Zero + + +class divisor_sigma(DefinedFunction): + r""" + Calculate the divisor function `\sigma_k(n)` for positive integer n + + ``divisor_sigma(n, k)`` is equal to ``sum([x**k for x in divisors(n)])`` + + If n's prime factorization is: + + .. math :: + n = \prod_{i=1}^\omega p_i^{m_i}, + + then + + .. math :: + \sigma_k(n) = \prod_{i=1}^\omega (1+p_i^k+p_i^{2k}+\cdots + + p_i^{m_ik}). + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import divisor_sigma + >>> divisor_sigma(18, 0) + 6 + >>> divisor_sigma(39, 1) + 56 + >>> divisor_sigma(12, 2) + 210 + >>> divisor_sigma(37) + 38 + + See Also + ======== + + sympy.ntheory.factor_.divisor_count, totient, sympy.ntheory.factor_.divisors, sympy.ntheory.factor_.factorint + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Divisor_function + + """ + is_integer = True + is_positive = True + + @classmethod + def eval(cls, n, k=S.One): + if n.is_integer is False: + raise TypeError("n should be an integer") + if n.is_positive is False: + raise ValueError("n should be a positive integer") + if k.is_integer is False: + raise TypeError("k should be an integer") + if k.is_nonnegative is False: + raise ValueError("k should be a nonnegative integer") + if n.is_prime is True: + return 1 + n**k + if n is S.One: + return S.One + if n.is_Integer is True: + if k.is_zero is True: + return Mul(*[e + 1 for e in factorint(n).values()]) + if k.is_Integer is True: + return S(_divisor_sigma(as_int(n), as_int(k))) + if k.is_zero is False: + return Mul(*[cancel((p**(k*(e + 1)) - 1) / (p**k - 1)) for p, e in factorint(n).items()]) + + +class udivisor_sigma(DefinedFunction): + r""" + Calculate the unitary divisor function `\sigma_k^*(n)` for positive integer n + + ``udivisor_sigma(n, k)`` is equal to ``sum([x**k for x in udivisors(n)])`` + + If n's prime factorization is: + + .. math :: + n = \prod_{i=1}^\omega p_i^{m_i}, + + then + + .. math :: + \sigma_k^*(n) = \prod_{i=1}^\omega (1+ p_i^{m_ik}). + + Parameters + ========== + + k : power of divisors in the sum + + for k = 0, 1: + ``udivisor_sigma(n, 0)`` is equal to ``udivisor_count(n)`` + ``udivisor_sigma(n, 1)`` is equal to ``sum(udivisors(n))`` + + Default for k is 1. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import udivisor_sigma + >>> udivisor_sigma(18, 0) + 4 + >>> udivisor_sigma(74, 1) + 114 + >>> udivisor_sigma(36, 3) + 47450 + >>> udivisor_sigma(111) + 152 + + See Also + ======== + + sympy.ntheory.factor_.divisor_count, totient, sympy.ntheory.factor_.divisors, + sympy.ntheory.factor_.udivisors, sympy.ntheory.factor_.udivisor_count, divisor_sigma, + sympy.ntheory.factor_.factorint + + References + ========== + + .. [1] https://mathworld.wolfram.com/UnitaryDivisorFunction.html + + """ + is_integer = True + is_positive = True + + @classmethod + def eval(cls, n, k=S.One): + if n.is_integer is False: + raise TypeError("n should be an integer") + if n.is_positive is False: + raise ValueError("n should be a positive integer") + if k.is_integer is False: + raise TypeError("k should be an integer") + if k.is_nonnegative is False: + raise ValueError("k should be a nonnegative integer") + if n.is_prime is True: + return 1 + n**k + if n.is_Integer: + return Mul(*[1+p**(k*e) for p, e in factorint(n).items()]) + + +class legendre_symbol(DefinedFunction): + r""" + Returns the Legendre symbol `(a / p)`. + + For an integer ``a`` and an odd prime ``p``, the Legendre symbol is + defined as + + .. math :: + \genfrac(){}{}{a}{p} = \begin{cases} + 0 & \text{if } p \text{ divides } a\\ + 1 & \text{if } a \text{ is a quadratic residue modulo } p\\ + -1 & \text{if } a \text{ is a quadratic nonresidue modulo } p + \end{cases} + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import legendre_symbol + >>> [legendre_symbol(i, 7) for i in range(7)] + [0, 1, 1, -1, 1, -1, -1] + >>> sorted(set([i**2 % 7 for i in range(7)])) + [0, 1, 2, 4] + + See Also + ======== + + sympy.ntheory.residue_ntheory.is_quad_residue, jacobi_symbol + + """ + is_integer = True + is_prime = False + + @classmethod + def eval(cls, a, p): + if a.is_integer is False: + raise TypeError("a should be an integer") + if p.is_integer is False: + raise TypeError("p should be an integer") + if p.is_prime is False or p.is_odd is False: + raise ValueError("p should be an odd prime integer") + if (a % p).is_zero is True: + return S.Zero + if a is S.One: + return S.One + if a.is_Integer is True and p.is_Integer is True: + return S(legendre(as_int(a), as_int(p))) + + +class jacobi_symbol(DefinedFunction): + r""" + Returns the Jacobi symbol `(m / n)`. + + For any integer ``m`` and any positive odd integer ``n`` the Jacobi symbol + is defined as the product of the Legendre symbols corresponding to the + prime factors of ``n``: + + .. math :: + \genfrac(){}{}{m}{n} = + \genfrac(){}{}{m}{p^{1}}^{\alpha_1} + \genfrac(){}{}{m}{p^{2}}^{\alpha_2} + ... + \genfrac(){}{}{m}{p^{k}}^{\alpha_k} + \text{ where } n = + p_1^{\alpha_1} + p_2^{\alpha_2} + ... + p_k^{\alpha_k} + + Like the Legendre symbol, if the Jacobi symbol `\genfrac(){}{}{m}{n} = -1` + then ``m`` is a quadratic nonresidue modulo ``n``. + + But, unlike the Legendre symbol, if the Jacobi symbol + `\genfrac(){}{}{m}{n} = 1` then ``m`` may or may not be a quadratic residue + modulo ``n``. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import jacobi_symbol, legendre_symbol + >>> from sympy import S + >>> jacobi_symbol(45, 77) + -1 + >>> jacobi_symbol(60, 121) + 1 + + The relationship between the ``jacobi_symbol`` and ``legendre_symbol`` can + be demonstrated as follows: + + >>> L = legendre_symbol + >>> S(45).factors() + {3: 2, 5: 1} + >>> jacobi_symbol(7, 45) == L(7, 3)**2 * L(7, 5)**1 + True + + See Also + ======== + + sympy.ntheory.residue_ntheory.is_quad_residue, legendre_symbol + + """ + is_integer = True + is_prime = False + + @classmethod + def eval(cls, m, n): + if m.is_integer is False: + raise TypeError("m should be an integer") + if n.is_integer is False: + raise TypeError("n should be an integer") + if n.is_positive is False or n.is_odd is False: + raise ValueError("n should be an odd positive integer") + if m is S.One or n is S.One: + return S.One + if (m % n).is_zero is True: + return S.Zero + if m.is_Integer is True and n.is_Integer is True: + return S(jacobi(as_int(m), as_int(n))) + + +class kronecker_symbol(DefinedFunction): + r""" + Returns the Kronecker symbol `(a / n)`. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import kronecker_symbol + >>> kronecker_symbol(45, 77) + -1 + >>> kronecker_symbol(13, -120) + 1 + + See Also + ======== + + jacobi_symbol, legendre_symbol + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Kronecker_symbol + + """ + is_integer = True + is_prime = False + + @classmethod + def eval(cls, a, n): + if a.is_integer is False: + raise TypeError("a should be an integer") + if n.is_integer is False: + raise TypeError("n should be an integer") + if a is S.One or n is S.One: + return S.One + if a.is_Integer is True and n.is_Integer is True: + return S(kronecker(as_int(a), as_int(n))) + + +class mobius(DefinedFunction): + """ + Mobius function maps natural number to {-1, 0, 1} + + It is defined as follows: + 1) `1` if `n = 1`. + 2) `0` if `n` has a squared prime factor. + 3) `(-1)^k` if `n` is a square-free positive integer with `k` + number of prime factors. + + It is an important multiplicative function in number theory + and combinatorics. It has applications in mathematical series, + algebraic number theory and also physics (Fermion operator has very + concrete realization with Mobius Function model). + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import mobius + >>> mobius(13*7) + 1 + >>> mobius(1) + 1 + >>> mobius(13*7*5) + -1 + >>> mobius(13**2) + 0 + + Even in the case of a symbol, if it clearly contains a squared prime factor, it will be zero. + + >>> from sympy import Symbol + >>> n = Symbol("n", integer=True, positive=True) + >>> mobius(4*n) + 0 + >>> mobius(n**2) + 0 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/M%C3%B6bius_function + .. [2] Thomas Koshy "Elementary Number Theory with Applications" + .. [3] https://oeis.org/A008683 + + """ + is_integer = True + is_prime = False + + @classmethod + def eval(cls, n): + if n.is_integer is False: + raise TypeError("n should be an integer") + if n.is_positive is False: + raise ValueError("n should be a positive integer") + if n.is_prime is True: + return S.NegativeOne + if n is S.One: + return S.One + result = None + for m, e in (_.as_base_exp() for _ in Mul.make_args(n)): + if m.is_integer is True and m.is_positive is True and \ + e.is_integer is True and e.is_positive is True: + lt = is_lt(S.One, e) # 1 < e + if lt is True: + result = S.Zero + elif m.is_Integer is True: + factors = factorint(m) + if any(v > 1 for v in factors.values()): + result = S.Zero + elif lt is False: + s = S.NegativeOne if len(factors) % 2 else S.One + if result is None: + result = s + else: + result *= s + else: + return + return result + + +class primenu(DefinedFunction): + r""" + Calculate the number of distinct prime factors for a positive integer n. + + If n's prime factorization is: + + .. math :: + n = \prod_{i=1}^k p_i^{m_i}, + + then ``primenu(n)`` or `\nu(n)` is: + + .. math :: + \nu(n) = k. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import primenu + >>> primenu(1) + 0 + >>> primenu(30) + 3 + + See Also + ======== + + sympy.ntheory.factor_.factorint + + References + ========== + + .. [1] https://mathworld.wolfram.com/PrimeFactor.html + .. [2] https://oeis.org/A001221 + + """ + is_integer = True + is_nonnegative = True + + @classmethod + def eval(cls, n): + if n.is_integer is False: + raise TypeError("n should be an integer") + if n.is_positive is False: + raise ValueError("n should be a positive integer") + if n.is_prime is True: + return S.One + if n is S.One: + return S.Zero + if n.is_Integer is True: + return S(len(factorint(n))) + + +class primeomega(DefinedFunction): + r""" + Calculate the number of prime factors counting multiplicities for a + positive integer n. + + If n's prime factorization is: + + .. math :: + n = \prod_{i=1}^k p_i^{m_i}, + + then ``primeomega(n)`` or `\Omega(n)` is: + + .. math :: + \Omega(n) = \sum_{i=1}^k m_i. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import primeomega + >>> primeomega(1) + 0 + >>> primeomega(20) + 3 + + See Also + ======== + + sympy.ntheory.factor_.factorint + + References + ========== + + .. [1] https://mathworld.wolfram.com/PrimeFactor.html + .. [2] https://oeis.org/A001222 + + """ + is_integer = True + is_nonnegative = True + + @classmethod + def eval(cls, n): + if n.is_integer is False: + raise TypeError("n should be an integer") + if n.is_positive is False: + raise ValueError("n should be a positive integer") + if n.is_prime is True: + return S.One + if n is S.One: + return S.Zero + if n.is_Integer is True: + return S(sum(factorint(n).values())) + + +class totient(DefinedFunction): + r""" + Calculate the Euler totient function phi(n) + + ``totient(n)`` or `\phi(n)` is the number of positive integers `\leq` n + that are relatively prime to n. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import totient + >>> totient(1) + 1 + >>> totient(25) + 20 + >>> totient(45) == totient(5)*totient(9) + True + + See Also + ======== + + sympy.ntheory.factor_.divisor_count + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Euler%27s_totient_function + .. [2] https://mathworld.wolfram.com/TotientFunction.html + .. [3] https://oeis.org/A000010 + + """ + is_integer = True + is_positive = True + + @classmethod + def eval(cls, n): + if n.is_integer is False: + raise TypeError("n should be an integer") + if n.is_positive is False: + raise ValueError("n should be a positive integer") + if n is S.One: + return S.One + if n.is_prime is True: + return n - 1 + if isinstance(n, Dict): + return S(prod(p**(k-1)*(p-1) for p, k in n.items())) + if n.is_Integer is True: + return S(prod(p**(k-1)*(p-1) for p, k in factorint(n).items())) + + +class reduced_totient(DefinedFunction): + r""" + Calculate the Carmichael reduced totient function lambda(n) + + ``reduced_totient(n)`` or `\lambda(n)` is the smallest m > 0 such that + `k^m \equiv 1 \mod n` for all k relatively prime to n. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import reduced_totient + >>> reduced_totient(1) + 1 + >>> reduced_totient(8) + 2 + >>> reduced_totient(30) + 4 + + See Also + ======== + + totient + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Carmichael_function + .. [2] https://mathworld.wolfram.com/CarmichaelFunction.html + .. [3] https://oeis.org/A002322 + + """ + is_integer = True + is_positive = True + + @classmethod + def eval(cls, n): + if n.is_integer is False: + raise TypeError("n should be an integer") + if n.is_positive is False: + raise ValueError("n should be a positive integer") + if n is S.One: + return S.One + if n.is_prime is True: + return n - 1 + if isinstance(n, Dict): + t = 1 + if 2 in n: + t = (1 << (n[2] - 2)) if 2 < n[2] else n[2] + return S(lcm(int(t), *(int(p-1)*int(p)**int(k-1) for p, k in n.items() if p != 2))) + if n.is_Integer is True: + n, t = remove(int(n), 2) + if not t: + t = 1 + elif 2 < t: + t = 1 << (t - 2) + return S(lcm(t, *((p-1)*p**(k-1) for p, k in factorint(n).items()))) + + +class primepi(DefinedFunction): + r""" Represents the prime counting function pi(n) = the number + of prime numbers less than or equal to n. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import primepi + >>> from sympy import prime, prevprime, isprime + >>> primepi(25) + 9 + + So there are 9 primes less than or equal to 25. Is 25 prime? + + >>> isprime(25) + False + + It is not. So the first prime less than 25 must be the + 9th prime: + + >>> prevprime(25) == prime(9) + True + + See Also + ======== + + sympy.ntheory.primetest.isprime : Test if n is prime + sympy.ntheory.generate.primerange : Generate all primes in a given range + sympy.ntheory.generate.prime : Return the nth prime + + References + ========== + + .. [1] https://oeis.org/A000720 + + """ + is_integer = True + is_nonnegative = True + + @classmethod + def eval(cls, n): + if n is S.Infinity: + return S.Infinity + if n is S.NegativeInfinity: + return S.Zero + if n.is_real is False: + raise TypeError("n should be a real") + if is_lt(n, S(2)) is True: + return S.Zero + try: + n = int(n) + except TypeError: + return + return S(_primepi(n)) + + +####################################################################### +### +### Functions for enumerating partitions, permutations and combinations +### +####################################################################### + + +class _MultisetHistogram(tuple): + __slots__ = () + + +_N = -1 +_ITEMS = -2 +_M = slice(None, _ITEMS) + + +def _multiset_histogram(n): + """Return tuple used in permutation and combination counting. Input + is a dictionary giving items with counts as values or a sequence of + items (which need not be sorted). + + The data is stored in a class deriving from tuple so it is easily + recognized and so it can be converted easily to a list. + """ + if isinstance(n, dict): # item: count + if not all(isinstance(v, int) and v >= 0 for v in n.values()): + raise ValueError + tot = sum(n.values()) + items = sum(1 for k in n if n[k] > 0) + return _MultisetHistogram([n[k] for k in n if n[k] > 0] + [items, tot]) + else: + n = list(n) + s = set(n) + lens = len(s) + lenn = len(n) + if lens == lenn: + n = [1]*lenn + [lenn, lenn] + return _MultisetHistogram(n) + m = dict(zip(s, range(lens))) + d = dict(zip(range(lens), (0,)*lens)) + for i in n: + d[m[i]] += 1 + return _multiset_histogram(d) + + +def nP(n, k=None, replacement=False): + """Return the number of permutations of ``n`` items taken ``k`` at a time. + + Possible values for ``n``: + + integer - set of length ``n`` + + sequence - converted to a multiset internally + + multiset - {element: multiplicity} + + If ``k`` is None then the total of all permutations of length 0 + through the number of items represented by ``n`` will be returned. + + If ``replacement`` is True then a given item can appear more than once + in the ``k`` items. (For example, for 'ab' permutations of 2 would + include 'aa', 'ab', 'ba' and 'bb'.) The multiplicity of elements in + ``n`` is ignored when ``replacement`` is True but the total number + of elements is considered since no element can appear more times than + the number of elements in ``n``. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import nP + >>> from sympy.utilities.iterables import multiset_permutations, multiset + >>> nP(3, 2) + 6 + >>> nP('abc', 2) == nP(multiset('abc'), 2) == 6 + True + >>> nP('aab', 2) + 3 + >>> nP([1, 2, 2], 2) + 3 + >>> [nP(3, i) for i in range(4)] + [1, 3, 6, 6] + >>> nP(3) == sum(_) + True + + When ``replacement`` is True, each item can have multiplicity + equal to the length represented by ``n``: + + >>> nP('aabc', replacement=True) + 121 + >>> [len(list(multiset_permutations('aaaabbbbcccc', i))) for i in range(5)] + [1, 3, 9, 27, 81] + >>> sum(_) + 121 + + See Also + ======== + sympy.utilities.iterables.multiset_permutations + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Permutation + + """ + try: + n = as_int(n) + except ValueError: + return Integer(_nP(_multiset_histogram(n), k, replacement)) + return Integer(_nP(n, k, replacement)) + + +@cacheit +def _nP(n, k=None, replacement=False): + + if k == 0: + return 1 + if isinstance(n, SYMPY_INTS): # n different items + # assert n >= 0 + if k is None: + return sum(_nP(n, i, replacement) for i in range(n + 1)) + elif replacement: + return n**k + elif k > n: + return 0 + elif k == n: + return factorial(k) + elif k == 1: + return n + else: + # assert k >= 0 + return _product(n - k + 1, n) + elif isinstance(n, _MultisetHistogram): + if k is None: + return sum(_nP(n, i, replacement) for i in range(n[_N] + 1)) + elif replacement: + return n[_ITEMS]**k + elif k == n[_N]: + return factorial(k)/prod([factorial(i) for i in n[_M] if i > 1]) + elif k > n[_N]: + return 0 + elif k == 1: + return n[_ITEMS] + else: + # assert k >= 0 + tot = 0 + n = list(n) + for i in range(len(n[_M])): + if not n[i]: + continue + n[_N] -= 1 + if n[i] == 1: + n[i] = 0 + n[_ITEMS] -= 1 + tot += _nP(_MultisetHistogram(n), k - 1) + n[_ITEMS] += 1 + n[i] = 1 + else: + n[i] -= 1 + tot += _nP(_MultisetHistogram(n), k - 1) + n[i] += 1 + n[_N] += 1 + return tot + + +@cacheit +def _AOP_product(n): + """for n = (m1, m2, .., mk) return the coefficients of the polynomial, + prod(sum(x**i for i in range(nj + 1)) for nj in n); i.e. the coefficients + of the product of AOPs (all-one polynomials) or order given in n. The + resulting coefficient corresponding to x**r is the number of r-length + combinations of sum(n) elements with multiplicities given in n. + The coefficients are given as a default dictionary (so if a query is made + for a key that is not present, 0 will be returned). + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import _AOP_product + >>> from sympy.abc import x + >>> n = (2, 2, 3) # e.g. aabbccc + >>> prod = ((x**2 + x + 1)*(x**2 + x + 1)*(x**3 + x**2 + x + 1)).expand() + >>> c = _AOP_product(n); dict(c) + {0: 1, 1: 3, 2: 6, 3: 8, 4: 8, 5: 6, 6: 3, 7: 1} + >>> [c[i] for i in range(8)] == [prod.coeff(x, i) for i in range(8)] + True + + The generating poly used here is the same as that listed in + https://tinyurl.com/cep849r, but in a refactored form. + + """ + + n = list(n) + ord = sum(n) + need = (ord + 2)//2 + rv = [1]*(n.pop() + 1) + rv.extend((0,) * (need - len(rv))) + rv = rv[:need] + while n: + ni = n.pop() + N = ni + 1 + was = rv[:] + for i in range(1, min(N, len(rv))): + rv[i] += rv[i - 1] + for i in range(N, need): + rv[i] += rv[i - 1] - was[i - N] + rev = list(reversed(rv)) + if ord % 2: + rv = rv + rev + else: + rv[-1:] = rev + d = defaultdict(int) + for i, r in enumerate(rv): + d[i] = r + return d + + +def nC(n, k=None, replacement=False): + """Return the number of combinations of ``n`` items taken ``k`` at a time. + + Possible values for ``n``: + + integer - set of length ``n`` + + sequence - converted to a multiset internally + + multiset - {element: multiplicity} + + If ``k`` is None then the total of all combinations of length 0 + through the number of items represented in ``n`` will be returned. + + If ``replacement`` is True then a given item can appear more than once + in the ``k`` items. (For example, for 'ab' sets of 2 would include 'aa', + 'ab', and 'bb'.) The multiplicity of elements in ``n`` is ignored when + ``replacement`` is True but the total number of elements is considered + since no element can appear more times than the number of elements in + ``n``. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import nC + >>> from sympy.utilities.iterables import multiset_combinations + >>> nC(3, 2) + 3 + >>> nC('abc', 2) + 3 + >>> nC('aab', 2) + 2 + + When ``replacement`` is True, each item can have multiplicity + equal to the length represented by ``n``: + + >>> nC('aabc', replacement=True) + 35 + >>> [len(list(multiset_combinations('aaaabbbbcccc', i))) for i in range(5)] + [1, 3, 6, 10, 15] + >>> sum(_) + 35 + + If there are ``k`` items with multiplicities ``m_1, m_2, ..., m_k`` + then the total of all combinations of length 0 through ``k`` is the + product, ``(m_1 + 1)*(m_2 + 1)*...*(m_k + 1)``. When the multiplicity + of each item is 1 (i.e., k unique items) then there are 2**k + combinations. For example, if there are 4 unique items, the total number + of combinations is 16: + + >>> sum(nC(4, i) for i in range(5)) + 16 + + See Also + ======== + + sympy.utilities.iterables.multiset_combinations + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Combination + .. [2] https://tinyurl.com/cep849r + + """ + + if isinstance(n, SYMPY_INTS): + if k is None: + if not replacement: + return 2**n + return sum(nC(n, i, replacement) for i in range(n + 1)) + if k < 0: + raise ValueError("k cannot be negative") + if replacement: + return binomial(n + k - 1, k) + return binomial(n, k) + if isinstance(n, _MultisetHistogram): + N = n[_N] + if k is None: + if not replacement: + return prod(m + 1 for m in n[_M]) + return sum(nC(n, i, replacement) for i in range(N + 1)) + elif replacement: + return nC(n[_ITEMS], k, replacement) + # assert k >= 0 + elif k in (1, N - 1): + return n[_ITEMS] + elif k in (0, N): + return 1 + return _AOP_product(tuple(n[_M]))[k] + else: + return nC(_multiset_histogram(n), k, replacement) + + +def _eval_stirling1(n, k): + if n == k == 0: + return S.One + if 0 in (n, k): + return S.Zero + + # some special values + if n == k: + return S.One + elif k == n - 1: + return binomial(n, 2) + elif k == n - 2: + return (3*n - 1)*binomial(n, 3)/4 + elif k == n - 3: + return binomial(n, 2)*binomial(n, 4) + + return _stirling1(n, k) + + +@cacheit +def _stirling1(n, k): + row = [0, 1]+[0]*(k-1) # for n = 1 + for i in range(2, n+1): + for j in range(min(k,i), 0, -1): + row[j] = (i-1) * row[j] + row[j-1] + return Integer(row[k]) + + +def _eval_stirling2(n, k): + if n == k == 0: + return S.One + if 0 in (n, k): + return S.Zero + + # some special values + if n == k: + return S.One + elif k == n - 1: + return binomial(n, 2) + elif k == 1: + return S.One + elif k == 2: + return Integer(2**(n - 1) - 1) + + return _stirling2(n, k) + + +@cacheit +def _stirling2(n, k): + row = [0, 1]+[0]*(k-1) # for n = 1 + for i in range(2, n+1): + for j in range(min(k,i), 0, -1): + row[j] = j * row[j] + row[j-1] + return Integer(row[k]) + + +def stirling(n, k, d=None, kind=2, signed=False): + r"""Return Stirling number $S(n, k)$ of the first or second (default) kind. + + The sum of all Stirling numbers of the second kind for $k = 1$ + through $n$ is ``bell(n)``. The recurrence relationship for these numbers + is: + + .. math :: {0 \brace 0} = 1; {n \brace 0} = {0 \brace k} = 0; + + .. math :: {{n+1} \brace k} = j {n \brace k} + {n \brace {k-1}} + + where $j$ is: + $n$ for Stirling numbers of the first kind, + $-n$ for signed Stirling numbers of the first kind, + $k$ for Stirling numbers of the second kind. + + The first kind of Stirling number counts the number of permutations of + ``n`` distinct items that have ``k`` cycles; the second kind counts the + ways in which ``n`` distinct items can be partitioned into ``k`` parts. + If ``d`` is given, the "reduced Stirling number of the second kind" is + returned: $S^{d}(n, k) = S(n - d + 1, k - d + 1)$ with $n \ge k \ge d$. + (This counts the ways to partition $n$ consecutive integers into $k$ + groups with no pairwise difference less than $d$. See example below.) + + To obtain the signed Stirling numbers of the first kind, use keyword + ``signed=True``. Using this keyword automatically sets ``kind`` to 1. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import stirling, bell + >>> from sympy.combinatorics import Permutation + >>> from sympy.utilities.iterables import multiset_partitions, permutations + + First kind (unsigned by default): + + >>> [stirling(6, i, kind=1) for i in range(7)] + [0, 120, 274, 225, 85, 15, 1] + >>> perms = list(permutations(range(4))) + >>> [sum(Permutation(p).cycles == i for p in perms) for i in range(5)] + [0, 6, 11, 6, 1] + >>> [stirling(4, i, kind=1) for i in range(5)] + [0, 6, 11, 6, 1] + + First kind (signed): + + >>> [stirling(4, i, signed=True) for i in range(5)] + [0, -6, 11, -6, 1] + + Second kind: + + >>> [stirling(10, i) for i in range(12)] + [0, 1, 511, 9330, 34105, 42525, 22827, 5880, 750, 45, 1, 0] + >>> sum(_) == bell(10) + True + >>> len(list(multiset_partitions(range(4), 2))) == stirling(4, 2) + True + + Reduced second kind: + + >>> from sympy import subsets, oo + >>> def delta(p): + ... if len(p) == 1: + ... return oo + ... return min(abs(i[0] - i[1]) for i in subsets(p, 2)) + >>> parts = multiset_partitions(range(5), 3) + >>> d = 2 + >>> sum(1 for p in parts if all(delta(i) >= d for i in p)) + 7 + >>> stirling(5, 3, 2) + 7 + + See Also + ======== + sympy.utilities.iterables.multiset_partitions + + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Stirling_numbers_of_the_first_kind + .. [2] https://en.wikipedia.org/wiki/Stirling_numbers_of_the_second_kind + + """ + # TODO: make this a class like bell() + + n = as_int(n) + k = as_int(k) + if n < 0: + raise ValueError('n must be nonnegative') + if k > n: + return S.Zero + if d: + # assert k >= d + # kind is ignored -- only kind=2 is supported + return _eval_stirling2(n - d + 1, k - d + 1) + elif signed: + # kind is ignored -- only kind=1 is supported + return S.NegativeOne**(n - k)*_eval_stirling1(n, k) + + if kind == 1: + return _eval_stirling1(n, k) + elif kind == 2: + return _eval_stirling2(n, k) + else: + raise ValueError('kind must be 1 or 2, not %s' % k) + + +@cacheit +def _nT(n, k): + """Return the partitions of ``n`` items into ``k`` parts. This + is used by ``nT`` for the case when ``n`` is an integer.""" + # really quick exits + if k > n or k < 0: + return 0 + if k in (1, n): + return 1 + if k == 0: + return 0 + # exits that could be done below but this is quicker + if k == 2: + return n//2 + d = n - k + if d <= 3: + return d + # quick exit + if 3*k >= n: # or, equivalently, 2*k >= d + # all the information needed in this case + # will be in the cache needed to calculate + # partition(d), so... + # update cache + tot = _partition_rec(d) + # and correct for values not needed + if d - k > 0: + tot -= sum(_partition_rec.fetch_item(slice(d - k))) + return tot + # regular exit + # nT(n, k) = Sum(nT(n - k, m), (m, 1, k)); + # calculate needed nT(i, j) values + p = [1]*d + for i in range(2, k + 1): + for m in range(i + 1, d): + p[m] += p[m - i] + d -= 1 + # if p[0] were appended to the end of p then the last + # k values of p are the nT(n, j) values for 0 < j < k in reverse + # order p[-1] = nT(n, 1), p[-2] = nT(n, 2), etc.... Instead of + # putting the 1 from p[0] there, however, it is simply added to + # the sum below which is valid for 1 < k <= n//2 + return (1 + sum(p[1 - k:])) + + +def nT(n, k=None): + """Return the number of ``k``-sized partitions of ``n`` items. + + Possible values for ``n``: + + integer - ``n`` identical items + + sequence - converted to a multiset internally + + multiset - {element: multiplicity} + + Note: the convention for ``nT`` is different than that of ``nC`` and + ``nP`` in that + here an integer indicates ``n`` *identical* items instead of a set of + length ``n``; this is in keeping with the ``partitions`` function which + treats its integer-``n`` input like a list of ``n`` 1s. One can use + ``range(n)`` for ``n`` to indicate ``n`` distinct items. + + If ``k`` is None then the total number of ways to partition the elements + represented in ``n`` will be returned. + + Examples + ======== + + >>> from sympy.functions.combinatorial.numbers import nT + + Partitions of the given multiset: + + >>> [nT('aabbc', i) for i in range(1, 7)] + [1, 8, 11, 5, 1, 0] + >>> nT('aabbc') == sum(_) + True + + >>> [nT("mississippi", i) for i in range(1, 12)] + [1, 74, 609, 1521, 1768, 1224, 579, 197, 50, 9, 1] + + Partitions when all items are identical: + + >>> [nT(5, i) for i in range(1, 6)] + [1, 2, 2, 1, 1] + >>> nT('1'*5) == sum(_) + True + + When all items are different: + + >>> [nT(range(5), i) for i in range(1, 6)] + [1, 15, 25, 10, 1] + >>> nT(range(5)) == sum(_) + True + + Partitions of an integer expressed as a sum of positive integers: + + >>> from sympy import partition + >>> partition(4) + 5 + >>> nT(4, 1) + nT(4, 2) + nT(4, 3) + nT(4, 4) + 5 + >>> nT('1'*4) + 5 + + See Also + ======== + sympy.utilities.iterables.partitions + sympy.utilities.iterables.multiset_partitions + sympy.functions.combinatorial.numbers.partition + + References + ========== + + .. [1] https://web.archive.org/web/20210507012732/https://teaching.csse.uwa.edu.au/units/CITS7209/partition.pdf + + """ + + if isinstance(n, SYMPY_INTS): + # n identical items + if k is None: + return partition(n) + if isinstance(k, SYMPY_INTS): + n = as_int(n) + k = as_int(k) + return Integer(_nT(n, k)) + if not isinstance(n, _MultisetHistogram): + try: + # if n contains hashable items there is some + # quick handling that can be done + u = len(set(n)) + if u <= 1: + return nT(len(n), k) + elif u == len(n): + n = range(u) + raise TypeError + except TypeError: + n = _multiset_histogram(n) + N = n[_N] + if k is None and N == 1: + return 1 + if k in (1, N): + return 1 + if k == 2 or N == 2 and k is None: + m, r = divmod(N, 2) + rv = sum(nC(n, i) for i in range(1, m + 1)) + if not r: + rv -= nC(n, m)//2 + if k is None: + rv += 1 # for k == 1 + return rv + if N == n[_ITEMS]: + # all distinct + if k is None: + return bell(N) + return stirling(N, k) + m = MultisetPartitionTraverser() + if k is None: + return m.count_partitions(n[_M]) + # MultisetPartitionTraverser does not have a range-limited count + # method, so need to enumerate and count + tot = 0 + for discard in m.enum_range(n[_M], k-1, k): + tot += 1 + return tot + + +#-----------------------------------------------------------------------------# +# # +# Motzkin numbers # +# # +#-----------------------------------------------------------------------------# + + +class motzkin(DefinedFunction): + """ + The nth Motzkin number is the number + of ways of drawing non-intersecting chords + between n points on a circle (not necessarily touching + every point by a chord). The Motzkin numbers are named + after Theodore Motzkin and have diverse applications + in geometry, combinatorics and number theory. + + Motzkin numbers are the integer sequence defined by the + initial terms `M_0 = 1`, `M_1 = 1` and the two-term recurrence relation + `M_n = \frac{2*n + 1}{n + 2} * M_{n-1} + \frac{3n - 3}{n + 2} * M_{n-2}`. + + + Examples + ======== + + >>> from sympy import motzkin + + >>> motzkin.is_motzkin(5) + False + >>> motzkin.find_motzkin_numbers_in_range(2,300) + [2, 4, 9, 21, 51, 127] + >>> motzkin.find_motzkin_numbers_in_range(2,900) + [2, 4, 9, 21, 51, 127, 323, 835] + >>> motzkin.find_first_n_motzkins(10) + [1, 1, 2, 4, 9, 21, 51, 127, 323, 835] + + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Motzkin_number + .. [2] https://mathworld.wolfram.com/MotzkinNumber.html + + """ + + @staticmethod + def is_motzkin(n): + try: + n = as_int(n) + except ValueError: + return False + if n > 0: + if n in (1, 2): + return True + + tn1 = 1 + tn = 2 + i = 3 + while tn < n: + a = ((2*i + 1)*tn + (3*i - 3)*tn1)/(i + 2) + i += 1 + tn1 = tn + tn = a + + if tn == n: + return True + else: + return False + + else: + return False + + @staticmethod + def find_motzkin_numbers_in_range(x, y): + if 0 <= x <= y: + motzkins = [] + if x <= 1 <= y: + motzkins.append(1) + tn1 = 1 + tn = 2 + i = 3 + while tn <= y: + if tn >= x: + motzkins.append(tn) + a = ((2*i + 1)*tn + (3*i - 3)*tn1)/(i + 2) + i += 1 + tn1 = tn + tn = int(a) + + return motzkins + + else: + raise ValueError('The provided range is not valid. This condition should satisfy x <= y') + + @staticmethod + def find_first_n_motzkins(n): + try: + n = as_int(n) + except ValueError: + raise ValueError('The provided number must be a positive integer') + if n < 0: + raise ValueError('The provided number must be a positive integer') + motzkins = [1] + if n >= 1: + motzkins.append(1) + tn1 = 1 + tn = 2 + i = 3 + while i <= n: + motzkins.append(tn) + a = ((2*i + 1)*tn + (3*i - 3)*tn1)/(i + 2) + i += 1 + tn1 = tn + tn = int(a) + + return motzkins + + @staticmethod + @recurrence_memo([S.One, S.One]) + def _motzkin(n, prev): + return ((2*n + 1)*prev[-1] + (3*n - 3)*prev[-2]) // (n + 2) + + @classmethod + def eval(cls, n): + try: + n = as_int(n) + except ValueError: + raise ValueError('The provided number must be a positive integer') + if n < 0: + raise ValueError('The provided number must be a positive integer') + return Integer(cls._motzkin(n - 1)) + + +def nD(i=None, brute=None, *, n=None, m=None): + """return the number of derangements for: ``n`` unique items, ``i`` + items (as a sequence or multiset), or multiplicities, ``m`` given + as a sequence or multiset. + + Examples + ======== + + >>> from sympy.utilities.iterables import generate_derangements as enum + >>> from sympy.functions.combinatorial.numbers import nD + + A derangement ``d`` of sequence ``s`` has all ``d[i] != s[i]``: + + >>> set([''.join(i) for i in enum('abc')]) + {'bca', 'cab'} + >>> nD('abc') + 2 + + Input as iterable or dictionary (multiset form) is accepted: + + >>> assert nD([1, 2, 2, 3, 3, 3]) == nD({1: 1, 2: 2, 3: 3}) + + By default, a brute-force enumeration and count of multiset permutations + is only done if there are fewer than 9 elements. There may be cases when + there is high multiplicity with few unique elements that will benefit + from a brute-force enumeration, too. For this reason, the `brute` + keyword (default None) is provided. When False, the brute-force + enumeration will never be used. When True, it will always be used. + + >>> nD('1111222233', brute=True) + 44 + + For convenience, one may specify ``n`` distinct items using the + ``n`` keyword: + + >>> assert nD(n=3) == nD('abc') == 2 + + Since the number of derangments depends on the multiplicity of the + elements and not the elements themselves, it may be more convenient + to give a list or multiset of multiplicities using keyword ``m``: + + >>> assert nD('abc') == nD(m=(1,1,1)) == nD(m={1:3}) == 2 + + """ + from sympy.integrals.integrals import integrate + from sympy.functions.special.polynomials import laguerre + from sympy.abc import x + def ok(x): + if not isinstance(x, SYMPY_INTS): + raise TypeError('expecting integer values') + if x < 0: + raise ValueError('value must not be negative') + return True + + if (i, n, m).count(None) != 2: + raise ValueError('enter only 1 of i, n, or m') + if i is not None: + if isinstance(i, SYMPY_INTS): + raise TypeError('items must be a list or dictionary') + if not i: + return S.Zero + if type(i) is not dict: + s = list(i) + ms = multiset(s) + elif type(i) is dict: + all(ok(_) for _ in i.values()) + ms = {k: v for k, v in i.items() if v} + s = None + if not ms: + return S.Zero + N = sum(ms.values()) + counts = multiset(ms.values()) + nkey = len(ms) + elif n is not None: + ok(n) + if not n: + return S.Zero + return subfactorial(n) + elif m is not None: + if isinstance(m, dict): + all(ok(i) and ok(j) for i, j in m.items()) + counts = {k: v for k, v in m.items() if k*v} + elif iterable(m) or isinstance(m, str): + m = list(m) + all(ok(i) for i in m) + counts = multiset([i for i in m if i]) + else: + raise TypeError('expecting iterable') + if not counts: + return S.Zero + N = sum(k*v for k, v in counts.items()) + nkey = sum(counts.values()) + s = None + big = int(max(counts)) + if big == 1: # no repetition + return subfactorial(nkey) + nval = len(counts) + if big*2 > N: + return S.Zero + if big*2 == N: + if nkey == 2 and nval == 1: + return S.One # aaabbb + if nkey - 1 == big: # one element repeated + return factorial(big) # e.g. abc part of abcddd + if N < 9 and brute is None or brute: + # for all possibilities, this was found to be faster + if s is None: + s = [] + i = 0 + for m, v in counts.items(): + for j in range(v): + s.extend([i]*m) + i += 1 + return Integer(sum(1 for i in multiset_derangements(s))) + from sympy.functions.elementary.exponential import exp + return Integer(abs(integrate(exp(-x)*Mul(*[ + laguerre(i, x)**m for i, m in counts.items()]), (x, 0, oo)))) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/tests/test_comb_factorials.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/tests/test_comb_factorials.py new file mode 100644 index 0000000000000000000000000000000000000000..6e3986c56736cccec0b3370007e047a1f38f06d1 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/tests/test_comb_factorials.py @@ -0,0 +1,653 @@ +from sympy.concrete.products import Product +from sympy.core.function import expand_func +from sympy.core.mod import Mod +from sympy.core.mul import Mul +from sympy.core import EulerGamma +from sympy.core.numbers import (Float, I, Rational, nan, oo, pi, zoo) +from sympy.core.relational import Eq +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, Symbol, symbols) +from sympy.functions.combinatorial.factorials import (ff, rf, binomial, factorial, factorial2) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.special.gamma_functions import (gamma, polygamma) +from sympy.polys.polytools import Poly +from sympy.series.order import O +from sympy.simplify.simplify import simplify +from sympy.core.expr import unchanged +from sympy.core.function import ArgumentIndexError +from sympy.functions.combinatorial.factorials import subfactorial +from sympy.functions.special.gamma_functions import uppergamma +from sympy.testing.pytest import XFAIL, raises, slow + +#Solves and Fixes Issue #10388 - This is the updated test for the same solved issue + +def test_rf_eval_apply(): + x, y = symbols('x,y') + n, k = symbols('n k', integer=True) + m = Symbol('m', integer=True, nonnegative=True) + + assert rf(nan, y) is nan + assert rf(x, nan) is nan + + assert unchanged(rf, x, y) + + assert rf(oo, 0) == 1 + assert rf(-oo, 0) == 1 + + assert rf(oo, 6) is oo + assert rf(-oo, 7) is -oo + assert rf(-oo, 6) is oo + + assert rf(oo, -6) is oo + assert rf(-oo, -7) is oo + + assert rf(-1, pi) == 0 + assert rf(-5, 1 + I) == 0 + + assert unchanged(rf, -3, k) + assert unchanged(rf, x, Symbol('k', integer=False)) + assert rf(-3, Symbol('k', integer=False)) == 0 + assert rf(Symbol('x', negative=True, integer=True), Symbol('k', integer=False)) == 0 + + assert rf(x, 0) == 1 + assert rf(x, 1) == x + assert rf(x, 2) == x*(x + 1) + assert rf(x, 3) == x*(x + 1)*(x + 2) + assert rf(x, 5) == x*(x + 1)*(x + 2)*(x + 3)*(x + 4) + + assert rf(x, -1) == 1/(x - 1) + assert rf(x, -2) == 1/((x - 1)*(x - 2)) + assert rf(x, -3) == 1/((x - 1)*(x - 2)*(x - 3)) + + assert rf(1, 100) == factorial(100) + + assert rf(x**2 + 3*x, 2) == (x**2 + 3*x)*(x**2 + 3*x + 1) + assert isinstance(rf(x**2 + 3*x, 2), Mul) + assert rf(x**3 + x, -2) == 1/((x**3 + x - 1)*(x**3 + x - 2)) + + assert rf(Poly(x**2 + 3*x, x), 2) == Poly(x**4 + 8*x**3 + 19*x**2 + 12*x, x) + assert isinstance(rf(Poly(x**2 + 3*x, x), 2), Poly) + raises(ValueError, lambda: rf(Poly(x**2 + 3*x, x, y), 2)) + assert rf(Poly(x**3 + x, x), -2) == 1/(x**6 - 9*x**5 + 35*x**4 - 75*x**3 + 94*x**2 - 66*x + 20) + raises(ValueError, lambda: rf(Poly(x**3 + x, x, y), -2)) + + assert rf(x, m).is_integer is None + assert rf(n, k).is_integer is None + assert rf(n, m).is_integer is True + assert rf(n, k + pi).is_integer is False + assert rf(n, m + pi).is_integer is False + assert rf(pi, m).is_integer is False + + def check(x, k, o, n): + a, b = Dummy(), Dummy() + r = lambda x, k: o(a, b).rewrite(n).subs({a:x,b:k}) + for i in range(-5,5): + for j in range(-5,5): + assert o(i, j) == r(i, j), (o, n, i, j) + check(x, k, rf, ff) + check(x, k, rf, binomial) + check(n, k, rf, factorial) + check(x, y, rf, factorial) + check(x, y, rf, binomial) + + assert rf(x, k).rewrite(ff) == ff(x + k - 1, k) + assert rf(x, k).rewrite(gamma) == Piecewise( + (gamma(k + x)/gamma(x), x > 0), + ((-1)**k*gamma(1 - x)/gamma(-k - x + 1), True)) + assert rf(5, k).rewrite(gamma) == gamma(k + 5)/24 + assert rf(x, k).rewrite(binomial) == factorial(k)*binomial(x + k - 1, k) + assert rf(n, k).rewrite(factorial) == Piecewise( + (factorial(k + n - 1)/factorial(n - 1), n > 0), + ((-1)**k*factorial(-n)/factorial(-k - n), True)) + assert rf(5, k).rewrite(factorial) == factorial(k + 4)/24 + assert rf(x, y).rewrite(factorial) == rf(x, y) + assert rf(x, y).rewrite(binomial) == rf(x, y) + + import random + from mpmath import rf as mpmath_rf + for i in range(100): + x = -500 + 500 * random.random() + k = -500 + 500 * random.random() + assert (abs(mpmath_rf(x, k) - rf(x, k)) < 10**(-15)) + + +def test_ff_eval_apply(): + x, y = symbols('x,y') + n, k = symbols('n k', integer=True) + m = Symbol('m', integer=True, nonnegative=True) + + assert ff(nan, y) is nan + assert ff(x, nan) is nan + + assert unchanged(ff, x, y) + + assert ff(oo, 0) == 1 + assert ff(-oo, 0) == 1 + + assert ff(oo, 6) is oo + assert ff(-oo, 7) is -oo + assert ff(-oo, 6) is oo + + assert ff(oo, -6) is oo + assert ff(-oo, -7) is oo + + assert ff(x, 0) == 1 + assert ff(x, 1) == x + assert ff(x, 2) == x*(x - 1) + assert ff(x, 3) == x*(x - 1)*(x - 2) + assert ff(x, 5) == x*(x - 1)*(x - 2)*(x - 3)*(x - 4) + + assert ff(x, -1) == 1/(x + 1) + assert ff(x, -2) == 1/((x + 1)*(x + 2)) + assert ff(x, -3) == 1/((x + 1)*(x + 2)*(x + 3)) + + assert ff(100, 100) == factorial(100) + + assert ff(2*x**2 - 5*x, 2) == (2*x**2 - 5*x)*(2*x**2 - 5*x - 1) + assert isinstance(ff(2*x**2 - 5*x, 2), Mul) + assert ff(x**2 + 3*x, -2) == 1/((x**2 + 3*x + 1)*(x**2 + 3*x + 2)) + + assert ff(Poly(2*x**2 - 5*x, x), 2) == Poly(4*x**4 - 28*x**3 + 59*x**2 - 35*x, x) + assert isinstance(ff(Poly(2*x**2 - 5*x, x), 2), Poly) + raises(ValueError, lambda: ff(Poly(2*x**2 - 5*x, x, y), 2)) + assert ff(Poly(x**2 + 3*x, x), -2) == 1/(x**4 + 12*x**3 + 49*x**2 + 78*x + 40) + raises(ValueError, lambda: ff(Poly(x**2 + 3*x, x, y), -2)) + + + assert ff(x, m).is_integer is None + assert ff(n, k).is_integer is None + assert ff(n, m).is_integer is True + assert ff(n, k + pi).is_integer is False + assert ff(n, m + pi).is_integer is False + assert ff(pi, m).is_integer is False + + assert isinstance(ff(x, x), ff) + assert ff(n, n) == factorial(n) + + def check(x, k, o, n): + a, b = Dummy(), Dummy() + r = lambda x, k: o(a, b).rewrite(n).subs({a:x,b:k}) + for i in range(-5,5): + for j in range(-5,5): + assert o(i, j) == r(i, j), (o, n) + check(x, k, ff, rf) + check(x, k, ff, gamma) + check(n, k, ff, factorial) + check(x, k, ff, binomial) + check(x, y, ff, factorial) + check(x, y, ff, binomial) + + assert ff(x, k).rewrite(rf) == rf(x - k + 1, k) + assert ff(x, k).rewrite(gamma) == Piecewise( + (gamma(x + 1)/gamma(-k + x + 1), x >= 0), + ((-1)**k*gamma(k - x)/gamma(-x), True)) + assert ff(5, k).rewrite(gamma) == 120/gamma(6 - k) + assert ff(n, k).rewrite(factorial) == Piecewise( + (factorial(n)/factorial(-k + n), n >= 0), + ((-1)**k*factorial(k - n - 1)/factorial(-n - 1), True)) + assert ff(5, k).rewrite(factorial) == 120/factorial(5 - k) + assert ff(x, k).rewrite(binomial) == factorial(k) * binomial(x, k) + assert ff(x, y).rewrite(factorial) == ff(x, y) + assert ff(x, y).rewrite(binomial) == ff(x, y) + + import random + from mpmath import ff as mpmath_ff + for i in range(100): + x = -500 + 500 * random.random() + k = -500 + 500 * random.random() + a = mpmath_ff(x, k) + b = ff(x, k) + assert (abs(a - b) < abs(a) * 10**(-15)) + + +def test_rf_ff_eval_hiprec(): + maple = Float('6.9109401292234329956525265438452') + us = ff(18, Rational(2, 3)).evalf(32) + assert abs(us - maple)/us < 1e-31 + + maple = Float('6.8261540131125511557924466355367') + us = rf(18, Rational(2, 3)).evalf(32) + assert abs(us - maple)/us < 1e-31 + + maple = Float('34.007346127440197150854651814225') + us = rf(Float('4.4', 32), Float('2.2', 32)) + assert abs(us - maple)/us < 1e-31 + + +def test_rf_lambdify_mpmath(): + from sympy.utilities.lambdify import lambdify + x, y = symbols('x,y') + f = lambdify((x,y), rf(x, y), 'mpmath') + maple = Float('34.007346127440197') + us = f(4.4, 2.2) + assert abs(us - maple)/us < 1e-15 + + +def test_factorial(): + x = Symbol('x') + n = Symbol('n', integer=True) + k = Symbol('k', integer=True, nonnegative=True) + r = Symbol('r', integer=False) + s = Symbol('s', integer=False, negative=True) + t = Symbol('t', nonnegative=True) + u = Symbol('u', noninteger=True) + + assert factorial(-2) is zoo + assert factorial(0) == 1 + assert factorial(7) == 5040 + assert factorial(19) == 121645100408832000 + assert factorial(31) == 8222838654177922817725562880000000 + assert factorial(n).func == factorial + assert factorial(2*n).func == factorial + + assert factorial(x).is_integer is None + assert factorial(n).is_integer is None + assert factorial(k).is_integer + assert factorial(r).is_integer is None + + assert factorial(n).is_positive is None + assert factorial(k).is_positive + + assert factorial(x).is_real is None + assert factorial(n).is_real is None + assert factorial(k).is_real is True + assert factorial(r).is_real is None + assert factorial(s).is_real is True + assert factorial(t).is_real is True + assert factorial(u).is_real is True + + assert factorial(x).is_composite is None + assert factorial(n).is_composite is None + assert factorial(k).is_composite is None + assert factorial(k + 3).is_composite is True + assert factorial(r).is_composite is None + assert factorial(s).is_composite is None + assert factorial(t).is_composite is None + assert factorial(u).is_composite is None + + assert factorial(oo) is oo + + +def test_factorial_Mod(): + pr = Symbol('pr', prime=True) + p, q = 10**9 + 9, 10**9 + 33 # prime modulo + r, s = 10**7 + 5, 33333333 # composite modulo + assert Mod(factorial(pr - 1), pr) == pr - 1 + assert Mod(factorial(pr - 1), -pr) == -1 + assert Mod(factorial(r - 1, evaluate=False), r) == 0 + assert Mod(factorial(s - 1, evaluate=False), s) == 0 + assert Mod(factorial(p - 1, evaluate=False), p) == p - 1 + assert Mod(factorial(q - 1, evaluate=False), q) == q - 1 + assert Mod(factorial(p - 50, evaluate=False), p) == 854928834 + assert Mod(factorial(q - 1800, evaluate=False), q) == 905504050 + assert Mod(factorial(153, evaluate=False), r) == Mod(factorial(153), r) + assert Mod(factorial(255, evaluate=False), s) == Mod(factorial(255), s) + assert Mod(factorial(4, evaluate=False), 3) == S.Zero + assert Mod(factorial(5, evaluate=False), 6) == S.Zero + + +def test_factorial_diff(): + n = Symbol('n', integer=True) + + assert factorial(n).diff(n) == \ + gamma(1 + n)*polygamma(0, 1 + n) + assert factorial(n**2).diff(n) == \ + 2*n*gamma(1 + n**2)*polygamma(0, 1 + n**2) + raises(ArgumentIndexError, lambda: factorial(n**2).fdiff(2)) + + +def test_factorial_series(): + n = Symbol('n', integer=True) + + assert factorial(n).series(n, 0, 3) == \ + 1 - n*EulerGamma + n**2*(EulerGamma**2/2 + pi**2/12) + O(n**3) + + +def test_factorial_rewrite(): + n = Symbol('n', integer=True) + k = Symbol('k', integer=True, nonnegative=True) + + assert factorial(n).rewrite(gamma) == gamma(n + 1) + _i = Dummy('i') + assert factorial(k).rewrite(Product).dummy_eq(Product(_i, (_i, 1, k))) + assert factorial(n).rewrite(Product) == factorial(n) + + +def test_factorial2(): + n = Symbol('n', integer=True) + + assert factorial2(-1) == 1 + assert factorial2(0) == 1 + assert factorial2(7) == 105 + assert factorial2(8) == 384 + + # The following is exhaustive + tt = Symbol('tt', integer=True, nonnegative=True) + tte = Symbol('tte', even=True, nonnegative=True) + tpe = Symbol('tpe', even=True, positive=True) + tto = Symbol('tto', odd=True, nonnegative=True) + tf = Symbol('tf', integer=True, nonnegative=False) + tfe = Symbol('tfe', even=True, nonnegative=False) + tfo = Symbol('tfo', odd=True, nonnegative=False) + ft = Symbol('ft', integer=False, nonnegative=True) + ff = Symbol('ff', integer=False, nonnegative=False) + fn = Symbol('fn', integer=False) + nt = Symbol('nt', nonnegative=True) + nf = Symbol('nf', nonnegative=False) + nn = Symbol('nn') + z = Symbol('z', zero=True) + #Solves and Fixes Issue #10388 - This is the updated test for the same solved issue + raises(ValueError, lambda: factorial2(oo)) + raises(ValueError, lambda: factorial2(Rational(5, 2))) + raises(ValueError, lambda: factorial2(-4)) + assert factorial2(n).is_integer is None + assert factorial2(tt - 1).is_integer + assert factorial2(tte - 1).is_integer + assert factorial2(tpe - 3).is_integer + assert factorial2(tto - 4).is_integer + assert factorial2(tto - 2).is_integer + assert factorial2(tf).is_integer is None + assert factorial2(tfe).is_integer is None + assert factorial2(tfo).is_integer is None + assert factorial2(ft).is_integer is None + assert factorial2(ff).is_integer is None + assert factorial2(fn).is_integer is None + assert factorial2(nt).is_integer is None + assert factorial2(nf).is_integer is None + assert factorial2(nn).is_integer is None + + assert factorial2(n).is_positive is None + assert factorial2(tt - 1).is_positive is True + assert factorial2(tte - 1).is_positive is True + assert factorial2(tpe - 3).is_positive is True + assert factorial2(tpe - 1).is_positive is True + assert factorial2(tto - 2).is_positive is True + assert factorial2(tto - 1).is_positive is True + assert factorial2(tf).is_positive is None + assert factorial2(tfe).is_positive is None + assert factorial2(tfo).is_positive is None + assert factorial2(ft).is_positive is None + assert factorial2(ff).is_positive is None + assert factorial2(fn).is_positive is None + assert factorial2(nt).is_positive is None + assert factorial2(nf).is_positive is None + assert factorial2(nn).is_positive is None + + assert factorial2(tt).is_even is None + assert factorial2(tt).is_odd is None + assert factorial2(tte).is_even is None + assert factorial2(tte).is_odd is None + assert factorial2(tte + 2).is_even is True + assert factorial2(tpe).is_even is True + assert factorial2(tpe).is_odd is False + assert factorial2(tto).is_odd is True + assert factorial2(tf).is_even is None + assert factorial2(tf).is_odd is None + assert factorial2(tfe).is_even is None + assert factorial2(tfe).is_odd is None + assert factorial2(tfo).is_even is False + assert factorial2(tfo).is_odd is None + assert factorial2(z).is_even is False + assert factorial2(z).is_odd is True + + +def test_factorial2_rewrite(): + n = Symbol('n', integer=True) + assert factorial2(n).rewrite(gamma) == \ + 2**(n/2)*Piecewise((1, Eq(Mod(n, 2), 0)), (sqrt(2)/sqrt(pi), Eq(Mod(n, 2), 1)))*gamma(n/2 + 1) + assert factorial2(2*n).rewrite(gamma) == 2**n*gamma(n + 1) + assert factorial2(2*n + 1).rewrite(gamma) == \ + sqrt(2)*2**(n + S.Half)*gamma(n + Rational(3, 2))/sqrt(pi) + + +def test_binomial(): + x = Symbol('x') + n = Symbol('n', integer=True) + nz = Symbol('nz', integer=True, nonzero=True) + k = Symbol('k', integer=True) + kp = Symbol('kp', integer=True, positive=True) + kn = Symbol('kn', integer=True, negative=True) + u = Symbol('u', negative=True) + v = Symbol('v', nonnegative=True) + p = Symbol('p', positive=True) + z = Symbol('z', zero=True) + nt = Symbol('nt', integer=False) + kt = Symbol('kt', integer=False) + a = Symbol('a', integer=True, nonnegative=True) + b = Symbol('b', integer=True, nonnegative=True) + + assert binomial(0, 0) == 1 + assert binomial(1, 1) == 1 + assert binomial(10, 10) == 1 + assert binomial(n, z) == 1 + assert binomial(1, 2) == 0 + assert binomial(-1, 2) == 1 + assert binomial(1, -1) == 0 + assert binomial(-1, 1) == -1 + assert binomial(-1, -1) == 0 + assert binomial(S.Half, S.Half) == 1 + assert binomial(-10, 1) == -10 + assert binomial(-10, 7) == -11440 + assert binomial(n, -1) == 0 # holds for all integers (negative, zero, positive) + assert binomial(kp, -1) == 0 + assert binomial(nz, 0) == 1 + assert expand_func(binomial(n, 1)) == n + assert expand_func(binomial(n, 2)) == n*(n - 1)/2 + assert expand_func(binomial(n, n - 2)) == n*(n - 1)/2 + assert expand_func(binomial(n, n - 1)) == n + assert binomial(n, 3).func == binomial + assert binomial(n, 3).expand(func=True) == n**3/6 - n**2/2 + n/3 + assert expand_func(binomial(n, 3)) == n*(n - 2)*(n - 1)/6 + assert binomial(n, n).func == binomial # e.g. (-1, -1) == 0, (2, 2) == 1 + assert binomial(n, n + 1).func == binomial # e.g. (-1, 0) == 1 + assert binomial(kp, kp + 1) == 0 + assert binomial(kn, kn) == 0 # issue #14529 + assert binomial(n, u).func == binomial + assert binomial(kp, u).func == binomial + assert binomial(n, p).func == binomial + assert binomial(n, k).func == binomial + assert binomial(n, n + p).func == binomial + assert binomial(kp, kp + p).func == binomial + + assert expand_func(binomial(n, n - 3)) == n*(n - 2)*(n - 1)/6 + + assert binomial(n, k).is_integer + assert binomial(nt, k).is_integer is None + assert binomial(x, nt).is_integer is False + + assert binomial(gamma(25), 6) == 79232165267303928292058750056084441948572511312165380965440075720159859792344339983120618959044048198214221915637090855535036339620413440000 + assert binomial(1324, 47) == 906266255662694632984994480774946083064699457235920708992926525848438478406790323869952 + assert binomial(1735, 43) == 190910140420204130794758005450919715396159959034348676124678207874195064798202216379800 + assert binomial(2512, 53) == 213894469313832631145798303740098720367984955243020898718979538096223399813295457822575338958939834177325304000 + assert binomial(3383, 52) == 27922807788818096863529701501764372757272890613101645521813434902890007725667814813832027795881839396839287659777235 + assert binomial(4321, 51) == 124595639629264868916081001263541480185227731958274383287107643816863897851139048158022599533438936036467601690983780576 + + assert binomial(a, b).is_nonnegative is True + assert binomial(-1, 2, evaluate=False).is_nonnegative is True + assert binomial(10, 5, evaluate=False).is_nonnegative is True + assert binomial(10, -3, evaluate=False).is_nonnegative is True + assert binomial(-10, -3, evaluate=False).is_nonnegative is True + assert binomial(-10, 2, evaluate=False).is_nonnegative is True + assert binomial(-10, 1, evaluate=False).is_nonnegative is False + assert binomial(-10, 7, evaluate=False).is_nonnegative is False + + # issue #14625 + for _ in (pi, -pi, nt, v, a): + assert binomial(_, _) == 1 + assert binomial(_, _ - 1) == _ + assert isinstance(binomial(u, u), binomial) + assert isinstance(binomial(u, u - 1), binomial) + assert isinstance(binomial(x, x), binomial) + assert isinstance(binomial(x, x - 1), binomial) + + #issue #18802 + assert expand_func(binomial(x + 1, x)) == x + 1 + assert expand_func(binomial(x, x - 1)) == x + assert expand_func(binomial(x + 1, x - 1)) == x*(x + 1)/2 + assert expand_func(binomial(x**2 + 1, x**2)) == x**2 + 1 + + # issue #13980 and #13981 + assert binomial(-7, -5) == 0 + assert binomial(-23, -12) == 0 + assert binomial(Rational(13, 2), -10) == 0 + assert binomial(-49, -51) == 0 + + assert binomial(19, Rational(-7, 2)) == S(-68719476736)/(911337863661225*pi) + assert binomial(0, Rational(3, 2)) == S(-2)/(3*pi) + assert binomial(-3, Rational(-7, 2)) is zoo + assert binomial(kn, kt) is zoo + + assert binomial(nt, kt).func == binomial + assert binomial(nt, Rational(15, 6)) == 8*gamma(nt + 1)/(15*sqrt(pi)*gamma(nt - Rational(3, 2))) + assert binomial(Rational(20, 3), Rational(-10, 8)) == gamma(Rational(23, 3))/(gamma(Rational(-1, 4))*gamma(Rational(107, 12))) + assert binomial(Rational(19, 2), Rational(-7, 2)) == Rational(-1615, 8388608) + assert binomial(Rational(-13, 5), Rational(-7, 8)) == gamma(Rational(-8, 5))/(gamma(Rational(-29, 40))*gamma(Rational(1, 8))) + assert binomial(Rational(-19, 8), Rational(-13, 5)) == gamma(Rational(-11, 8))/(gamma(Rational(-8, 5))*gamma(Rational(49, 40))) + + # binomial for complexes + assert binomial(I, Rational(-89, 8)) == gamma(1 + I)/(gamma(Rational(-81, 8))*gamma(Rational(97, 8) + I)) + assert binomial(I, 2*I) == gamma(1 + I)/(gamma(1 - I)*gamma(1 + 2*I)) + assert binomial(-7, I) is zoo + assert binomial(Rational(-7, 6), I) == gamma(Rational(-1, 6))/(gamma(Rational(-1, 6) - I)*gamma(1 + I)) + assert binomial((1+2*I), (1+3*I)) == gamma(2 + 2*I)/(gamma(1 - I)*gamma(2 + 3*I)) + assert binomial(I, 5) == Rational(1, 3) - I/S(12) + assert binomial((2*I + 3), 7) == -13*I/S(63) + assert isinstance(binomial(I, n), binomial) + assert expand_func(binomial(3, 2, evaluate=False)) == 3 + assert expand_func(binomial(n, 0, evaluate=False)) == 1 + assert expand_func(binomial(n, -2, evaluate=False)) == 0 + assert expand_func(binomial(n, k)) == binomial(n, k) + + +def test_binomial_Mod(): + p, q = 10**5 + 3, 10**9 + 33 # prime modulo + r = 10**7 + 5 # composite modulo + + # A few tests to get coverage + # Lucas Theorem + assert Mod(binomial(156675, 4433, evaluate=False), p) == Mod(binomial(156675, 4433), p) + + # factorial Mod + assert Mod(binomial(1234, 432, evaluate=False), q) == Mod(binomial(1234, 432), q) + + # binomial factorize + assert Mod(binomial(253, 113, evaluate=False), r) == Mod(binomial(253, 113), r) + + # using Granville's generalisation of Lucas' Theorem + assert Mod(binomial(10**18, 10**12, evaluate=False), p*p) == 3744312326 + + +@slow +def test_binomial_Mod_slow(): + p, q = 10**5 + 3, 10**9 + 33 # prime modulo + r, s = 10**7 + 5, 33333333 # composite modulo + + n, k, m = symbols('n k m') + assert (binomial(n, k) % q).subs({n: s, k: p}) == Mod(binomial(s, p), q) + assert (binomial(n, k) % m).subs({n: 8, k: 5, m: 13}) == 4 + assert (binomial(9, k) % 7).subs(k, 2) == 1 + + # Lucas Theorem + assert Mod(binomial(123456, 43253, evaluate=False), p) == Mod(binomial(123456, 43253), p) + assert Mod(binomial(-178911, 237, evaluate=False), p) == Mod(-binomial(178911 + 237 - 1, 237), p) + assert Mod(binomial(-178911, 238, evaluate=False), p) == Mod(binomial(178911 + 238 - 1, 238), p) + + # factorial Mod + assert Mod(binomial(9734, 451, evaluate=False), q) == Mod(binomial(9734, 451), q) + assert Mod(binomial(-10733, 4459, evaluate=False), q) == Mod(binomial(-10733, 4459), q) + assert Mod(binomial(-15733, 4458, evaluate=False), q) == Mod(binomial(-15733, 4458), q) + assert Mod(binomial(23, -38, evaluate=False), q) is S.Zero + assert Mod(binomial(23, 38, evaluate=False), q) is S.Zero + + # binomial factorize + assert Mod(binomial(753, 119, evaluate=False), r) == Mod(binomial(753, 119), r) + assert Mod(binomial(3781, 948, evaluate=False), s) == Mod(binomial(3781, 948), s) + assert Mod(binomial(25773, 1793, evaluate=False), s) == Mod(binomial(25773, 1793), s) + assert Mod(binomial(-753, 118, evaluate=False), r) == Mod(binomial(-753, 118), r) + assert Mod(binomial(-25773, 1793, evaluate=False), s) == Mod(binomial(-25773, 1793), s) + + +def test_binomial_diff(): + n = Symbol('n', integer=True) + k = Symbol('k', integer=True) + + assert binomial(n, k).diff(n) == \ + (-polygamma(0, 1 + n - k) + polygamma(0, 1 + n))*binomial(n, k) + assert binomial(n**2, k**3).diff(n) == \ + 2*n*(-polygamma( + 0, 1 + n**2 - k**3) + polygamma(0, 1 + n**2))*binomial(n**2, k**3) + + assert binomial(n, k).diff(k) == \ + (-polygamma(0, 1 + k) + polygamma(0, 1 + n - k))*binomial(n, k) + assert binomial(n**2, k**3).diff(k) == \ + 3*k**2*(-polygamma( + 0, 1 + k**3) + polygamma(0, 1 + n**2 - k**3))*binomial(n**2, k**3) + raises(ArgumentIndexError, lambda: binomial(n, k).fdiff(3)) + + +def test_binomial_rewrite(): + n = Symbol('n', integer=True) + k = Symbol('k', integer=True) + x = Symbol('x') + + assert binomial(n, k).rewrite( + factorial) == factorial(n)/(factorial(k)*factorial(n - k)) + assert binomial( + n, k).rewrite(gamma) == gamma(n + 1)/(gamma(k + 1)*gamma(n - k + 1)) + assert binomial(n, k).rewrite(ff) == ff(n, k) / factorial(k) + assert binomial(n, x).rewrite(ff) == binomial(n, x) + + +@XFAIL +def test_factorial_simplify_fail(): + # simplify(factorial(x + 1).diff(x) - ((x + 1)*factorial(x)).diff(x))) == 0 + from sympy.abc import x + assert simplify(x*polygamma(0, x + 1) - x*polygamma(0, x + 2) + + polygamma(0, x + 1) - polygamma(0, x + 2) + 1) == 0 + + +def test_subfactorial(): + assert all(subfactorial(i) == ans for i, ans in enumerate( + [1, 0, 1, 2, 9, 44, 265, 1854, 14833, 133496])) + assert subfactorial(oo) is oo + assert subfactorial(nan) is nan + assert subfactorial(23) == 9510425471055777937262 + assert unchanged(subfactorial, 2.2) + + x = Symbol('x') + assert subfactorial(x).rewrite(uppergamma) == uppergamma(x + 1, -1)/S.Exp1 + + tt = Symbol('tt', integer=True, nonnegative=True) + tf = Symbol('tf', integer=True, nonnegative=False) + tn = Symbol('tf', integer=True) + ft = Symbol('ft', integer=False, nonnegative=True) + ff = Symbol('ff', integer=False, nonnegative=False) + fn = Symbol('ff', integer=False) + nt = Symbol('nt', nonnegative=True) + nf = Symbol('nf', nonnegative=False) + nn = Symbol('nf') + te = Symbol('te', even=True, nonnegative=True) + to = Symbol('to', odd=True, nonnegative=True) + assert subfactorial(tt).is_integer + assert subfactorial(tf).is_integer is None + assert subfactorial(tn).is_integer is None + assert subfactorial(ft).is_integer is None + assert subfactorial(ff).is_integer is None + assert subfactorial(fn).is_integer is None + assert subfactorial(nt).is_integer is None + assert subfactorial(nf).is_integer is None + assert subfactorial(nn).is_integer is None + assert subfactorial(tt).is_nonnegative + assert subfactorial(tf).is_nonnegative is None + assert subfactorial(tn).is_nonnegative is None + assert subfactorial(ft).is_nonnegative is None + assert subfactorial(ff).is_nonnegative is None + assert subfactorial(fn).is_nonnegative is None + assert subfactorial(nt).is_nonnegative is None + assert subfactorial(nf).is_nonnegative is None + assert subfactorial(nn).is_nonnegative is None + assert subfactorial(tt).is_even is None + assert subfactorial(tt).is_odd is None + assert subfactorial(te).is_odd is True + assert subfactorial(to).is_even is True diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/tests/test_comb_numbers.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/tests/test_comb_numbers.py new file mode 100644 index 0000000000000000000000000000000000000000..83a7de89ed8e4fcc433d29f41fc87b9d0d397539 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/combinatorial/tests/test_comb_numbers.py @@ -0,0 +1,1250 @@ +import string + +from sympy.concrete.products import Product +from sympy.concrete.summations import Sum +from sympy.core.function import (diff, expand_func) +from sympy.core import (EulerGamma, TribonacciConstant) +from sympy.core.numbers import (Float, I, Rational, oo, pi) +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, Symbol, symbols) +from sympy.functions.combinatorial.numbers import carmichael +from sympy.functions.elementary.complexes import (im, re) +from sympy.functions.elementary.integers import floor +from sympy.polys.polytools import cancel +from sympy.series.limits import limit, Limit +from sympy.series.order import O +from sympy.functions import ( + bernoulli, harmonic, bell, fibonacci, tribonacci, lucas, euler, catalan, + genocchi, andre, partition, divisor_sigma, udivisor_sigma, legendre_symbol, + jacobi_symbol, kronecker_symbol, mobius, + primenu, primeomega, totient, reduced_totient, primepi, + motzkin, binomial, gamma, sqrt, cbrt, hyper, log, digamma, + trigamma, polygamma, factorial, sin, cos, cot, polylog, zeta, dirichlet_eta) +from sympy.functions.combinatorial.numbers import _nT +from sympy.ntheory.factor_ import factorint + +from sympy.core.expr import unchanged +from sympy.core.numbers import GoldenRatio, Integer + +from sympy.testing.pytest import raises, nocache_fail, warns_deprecated_sympy +from sympy.abc import x + + +def test_carmichael(): + with warns_deprecated_sympy(): + assert carmichael.is_prime(2821) == False + + +def test_bernoulli(): + assert bernoulli(0) == 1 + assert bernoulli(1) == Rational(1, 2) + assert bernoulli(2) == Rational(1, 6) + assert bernoulli(3) == 0 + assert bernoulli(4) == Rational(-1, 30) + assert bernoulli(5) == 0 + assert bernoulli(6) == Rational(1, 42) + assert bernoulli(7) == 0 + assert bernoulli(8) == Rational(-1, 30) + assert bernoulli(10) == Rational(5, 66) + assert bernoulli(1000001) == 0 + + assert bernoulli(0, x) == 1 + assert bernoulli(1, x) == x - S.Half + assert bernoulli(2, x) == x**2 - x + Rational(1, 6) + assert bernoulli(3, x) == x**3 - (3*x**2)/2 + x/2 + + # Should be fast; computed with mpmath + b = bernoulli(1000) + assert b.p % 10**10 == 7950421099 + assert b.q == 342999030 + + b = bernoulli(10**6, evaluate=False).evalf() + assert str(b) == '-2.23799235765713e+4767529' + + # Issue #8527 + l = Symbol('l', integer=True) + m = Symbol('m', integer=True, nonnegative=True) + n = Symbol('n', integer=True, positive=True) + assert isinstance(bernoulli(2 * l + 1), bernoulli) + assert isinstance(bernoulli(2 * m + 1), bernoulli) + assert bernoulli(2 * n + 1) == 0 + + assert bernoulli(x, 1) == bernoulli(x) + + assert str(bernoulli(0.0, 2.3).evalf(n=10)) == '1.000000000' + assert str(bernoulli(1.0).evalf(n=10)) == '0.5000000000' + assert str(bernoulli(1.2).evalf(n=10)) == '0.4195995367' + assert str(bernoulli(1.2, 0.8).evalf(n=10)) == '0.2144830348' + assert str(bernoulli(1.2, -0.8).evalf(n=10)) == '-1.158865646 - 0.6745558744*I' + assert str(bernoulli(3.0, 1j).evalf(n=10)) == '1.5 - 0.5*I' + assert str(bernoulli(I).evalf(n=10)) == '0.9268485643 - 0.5821580598*I' + assert str(bernoulli(I, I).evalf(n=10)) == '0.1267792071 + 0.01947413152*I' + assert bernoulli(x).evalf() == bernoulli(x) + + +def test_bernoulli_rewrite(): + from sympy.functions.elementary.piecewise import Piecewise + n = Symbol('n', integer=True, nonnegative=True) + + assert bernoulli(-1).rewrite(zeta) == pi**2/6 + assert bernoulli(-2).rewrite(zeta) == 2*zeta(3) + assert not bernoulli(n, -3).rewrite(zeta).has(harmonic) + assert bernoulli(-4, x).rewrite(zeta) == 4*zeta(5, x) + assert isinstance(bernoulli(n, x).rewrite(zeta), Piecewise) + assert bernoulli(n+1, x).rewrite(zeta) == -(n+1) * zeta(-n, x) + + +def test_fibonacci(): + assert [fibonacci(n) for n in range(-3, 5)] == [2, -1, 1, 0, 1, 1, 2, 3] + assert fibonacci(100) == 354224848179261915075 + assert [lucas(n) for n in range(-3, 5)] == [-4, 3, -1, 2, 1, 3, 4, 7] + assert lucas(100) == 792070839848372253127 + + assert fibonacci(1, x) == 1 + assert fibonacci(2, x) == x + assert fibonacci(3, x) == x**2 + 1 + assert fibonacci(4, x) == x**3 + 2*x + + # issue #8800 + n = Dummy('n') + assert fibonacci(n).limit(n, S.Infinity) is S.Infinity + assert lucas(n).limit(n, S.Infinity) is S.Infinity + + assert fibonacci(n).rewrite(sqrt) == \ + 2**(-n)*sqrt(5)*((1 + sqrt(5))**n - (-sqrt(5) + 1)**n) / 5 + assert fibonacci(n).rewrite(sqrt).subs(n, 10).expand() == fibonacci(10) + assert fibonacci(n).rewrite(GoldenRatio).subs(n,10).evalf() == \ + Float(fibonacci(10)) + assert lucas(n).rewrite(sqrt) == \ + (fibonacci(n-1).rewrite(sqrt) + fibonacci(n+1).rewrite(sqrt)).simplify() + assert lucas(n).rewrite(sqrt).subs(n, 10).expand() == lucas(10) + raises(ValueError, lambda: fibonacci(-3, x)) + + +def test_tribonacci(): + assert [tribonacci(n) for n in range(8)] == [0, 1, 1, 2, 4, 7, 13, 24] + assert tribonacci(100) == 98079530178586034536500564 + + assert tribonacci(0, x) == 0 + assert tribonacci(1, x) == 1 + assert tribonacci(2, x) == x**2 + assert tribonacci(3, x) == x**4 + x + assert tribonacci(4, x) == x**6 + 2*x**3 + 1 + assert tribonacci(5, x) == x**8 + 3*x**5 + 3*x**2 + + n = Dummy('n') + assert tribonacci(n).limit(n, S.Infinity) is S.Infinity + + w = (-1 + S.ImaginaryUnit * sqrt(3)) / 2 + a = (1 + cbrt(19 + 3*sqrt(33)) + cbrt(19 - 3*sqrt(33))) / 3 + b = (1 + w*cbrt(19 + 3*sqrt(33)) + w**2*cbrt(19 - 3*sqrt(33))) / 3 + c = (1 + w**2*cbrt(19 + 3*sqrt(33)) + w*cbrt(19 - 3*sqrt(33))) / 3 + assert tribonacci(n).rewrite(sqrt) == \ + (a**(n + 1)/((a - b)*(a - c)) + + b**(n + 1)/((b - a)*(b - c)) + + c**(n + 1)/((c - a)*(c - b))) + assert tribonacci(n).rewrite(sqrt).subs(n, 4).simplify() == tribonacci(4) + assert tribonacci(n).rewrite(GoldenRatio).subs(n,10).evalf() == \ + Float(tribonacci(10)) + assert tribonacci(n).rewrite(TribonacciConstant) == floor( + 3*TribonacciConstant**n*(102*sqrt(33) + 586)**Rational(1, 3)/ + (-2*(102*sqrt(33) + 586)**Rational(1, 3) + 4 + (102*sqrt(33) + + 586)**Rational(2, 3)) + S.Half) + raises(ValueError, lambda: tribonacci(-1, x)) + + +@nocache_fail +def test_bell(): + assert [bell(n) for n in range(8)] == [1, 1, 2, 5, 15, 52, 203, 877] + + assert bell(0, x) == 1 + assert bell(1, x) == x + assert bell(2, x) == x**2 + x + assert bell(5, x) == x**5 + 10*x**4 + 25*x**3 + 15*x**2 + x + assert bell(oo) is S.Infinity + raises(ValueError, lambda: bell(oo, x)) + + raises(ValueError, lambda: bell(-1)) + raises(ValueError, lambda: bell(S.Half)) + + X = symbols('x:6') + # X = (x0, x1, .. x5) + # at the same time: X[1] = x1, X[2] = x2 for standard readablity. + # but we must supply zero-based indexed object X[1:] = (x1, .. x5) + + assert bell(6, 2, X[1:]) == 6*X[5]*X[1] + 15*X[4]*X[2] + 10*X[3]**2 + assert bell( + 6, 3, X[1:]) == 15*X[4]*X[1]**2 + 60*X[3]*X[2]*X[1] + 15*X[2]**3 + + X = (1, 10, 100, 1000, 10000) + assert bell(6, 2, X) == (6 + 15 + 10)*10000 + + X = (1, 2, 3, 3, 5) + assert bell(6, 2, X) == 6*5 + 15*3*2 + 10*3**2 + + X = (1, 2, 3, 5) + assert bell(6, 3, X) == 15*5 + 60*3*2 + 15*2**3 + + # Dobinski's formula + n = Symbol('n', integer=True, nonnegative=True) + # For large numbers, this is too slow + # For nonintegers, there are significant precision errors + for i in [0, 2, 3, 7, 13, 42, 55]: + # Running without the cache this is either very slow or goes into an + # infinite loop. + assert bell(i).evalf() == bell(n).rewrite(Sum).evalf(subs={n: i}) + + m = Symbol("m") + assert bell(m).rewrite(Sum) == bell(m) + assert bell(n, m).rewrite(Sum) == bell(n, m) + # issue 9184 + n = Dummy('n') + assert bell(n).limit(n, S.Infinity) is S.Infinity + + +def test_harmonic(): + n = Symbol("n") + m = Symbol("m") + + assert harmonic(n, 0) == n + assert harmonic(n).evalf() == harmonic(n) + assert harmonic(n, 1) == harmonic(n) + assert harmonic(1, n) == 1 + + assert harmonic(0, 1) == 0 + assert harmonic(1, 1) == 1 + assert harmonic(2, 1) == Rational(3, 2) + assert harmonic(3, 1) == Rational(11, 6) + assert harmonic(4, 1) == Rational(25, 12) + assert harmonic(0, 2) == 0 + assert harmonic(1, 2) == 1 + assert harmonic(2, 2) == Rational(5, 4) + assert harmonic(3, 2) == Rational(49, 36) + assert harmonic(4, 2) == Rational(205, 144) + assert harmonic(0, 3) == 0 + assert harmonic(1, 3) == 1 + assert harmonic(2, 3) == Rational(9, 8) + assert harmonic(3, 3) == Rational(251, 216) + assert harmonic(4, 3) == Rational(2035, 1728) + + assert harmonic(oo, -1) is S.NaN + assert harmonic(oo, 0) is oo + assert harmonic(oo, S.Half) is oo + assert harmonic(oo, 1) is oo + assert harmonic(oo, 2) == (pi**2)/6 + assert harmonic(oo, 3) == zeta(3) + assert harmonic(oo, Dummy(negative=True)) is S.NaN + ip = Dummy(integer=True, positive=True) + if (1/ip <= 1) is True: #---------------------------------+ + assert None, 'delete this if-block and the next line' #| + ip = Dummy(even=True, positive=True) #--------------------+ + assert harmonic(oo, 1/ip) is oo + assert harmonic(oo, 1 + ip) is zeta(1 + ip) + + assert harmonic(0, m) == 0 + assert harmonic(-1, -1) == 0 + assert harmonic(-1, 0) == -1 + assert harmonic(-1, 1) is S.ComplexInfinity + assert harmonic(-1, 2) is S.NaN + assert harmonic(-3, -2) == -5 + assert harmonic(-3, -3) == 9 + + +def test_harmonic_rational(): + ne = S(6) + no = S(5) + pe = S(8) + po = S(9) + qe = S(10) + qo = S(13) + + Heee = harmonic(ne + pe/qe) + Aeee = (-log(10) + 2*(Rational(-1, 4) + sqrt(5)/4)*log(sqrt(-sqrt(5)/8 + Rational(5, 8))) + + 2*(-sqrt(5)/4 - Rational(1, 4))*log(sqrt(sqrt(5)/8 + Rational(5, 8))) + + pi*sqrt(2*sqrt(5)/5 + 1)/2 + Rational(13944145, 4720968)) + + Heeo = harmonic(ne + pe/qo) + Aeeo = (-log(26) + 2*log(sin(pi*Rational(3, 13)))*cos(pi*Rational(4, 13)) + 2*log(sin(pi*Rational(2, 13)))*cos(pi*Rational(32, 13)) + + 2*log(sin(pi*Rational(5, 13)))*cos(pi*Rational(80, 13)) - 2*log(sin(pi*Rational(6, 13)))*cos(pi*Rational(5, 13)) + - 2*log(sin(pi*Rational(4, 13)))*cos(pi/13) + pi*cot(pi*Rational(5, 13))/2 - 2*log(sin(pi/13))*cos(pi*Rational(3, 13)) + + Rational(2422020029, 702257080)) + + Heoe = harmonic(ne + po/qe) + Aeoe = (-log(20) + 2*(Rational(1, 4) + sqrt(5)/4)*log(Rational(-1, 4) + sqrt(5)/4) + + 2*(Rational(-1, 4) + sqrt(5)/4)*log(sqrt(-sqrt(5)/8 + Rational(5, 8))) + + 2*(-sqrt(5)/4 - Rational(1, 4))*log(sqrt(sqrt(5)/8 + Rational(5, 8))) + + 2*(-sqrt(5)/4 + Rational(1, 4))*log(Rational(1, 4) + sqrt(5)/4) + + Rational(11818877030, 4286604231) + pi*sqrt(2*sqrt(5) + 5)/2) + + Heoo = harmonic(ne + po/qo) + Aeoo = (-log(26) + 2*log(sin(pi*Rational(3, 13)))*cos(pi*Rational(54, 13)) + 2*log(sin(pi*Rational(4, 13)))*cos(pi*Rational(6, 13)) + + 2*log(sin(pi*Rational(6, 13)))*cos(pi*Rational(108, 13)) - 2*log(sin(pi*Rational(5, 13)))*cos(pi/13) + - 2*log(sin(pi/13))*cos(pi*Rational(5, 13)) + pi*cot(pi*Rational(4, 13))/2 + - 2*log(sin(pi*Rational(2, 13)))*cos(pi*Rational(3, 13)) + Rational(11669332571, 3628714320)) + + Hoee = harmonic(no + pe/qe) + Aoee = (-log(10) + 2*(Rational(-1, 4) + sqrt(5)/4)*log(sqrt(-sqrt(5)/8 + Rational(5, 8))) + + 2*(-sqrt(5)/4 - Rational(1, 4))*log(sqrt(sqrt(5)/8 + Rational(5, 8))) + + pi*sqrt(2*sqrt(5)/5 + 1)/2 + Rational(779405, 277704)) + + Hoeo = harmonic(no + pe/qo) + Aoeo = (-log(26) + 2*log(sin(pi*Rational(3, 13)))*cos(pi*Rational(4, 13)) + 2*log(sin(pi*Rational(2, 13)))*cos(pi*Rational(32, 13)) + + 2*log(sin(pi*Rational(5, 13)))*cos(pi*Rational(80, 13)) - 2*log(sin(pi*Rational(6, 13)))*cos(pi*Rational(5, 13)) + - 2*log(sin(pi*Rational(4, 13)))*cos(pi/13) + pi*cot(pi*Rational(5, 13))/2 + - 2*log(sin(pi/13))*cos(pi*Rational(3, 13)) + Rational(53857323, 16331560)) + + Hooe = harmonic(no + po/qe) + Aooe = (-log(20) + 2*(Rational(1, 4) + sqrt(5)/4)*log(Rational(-1, 4) + sqrt(5)/4) + + 2*(Rational(-1, 4) + sqrt(5)/4)*log(sqrt(-sqrt(5)/8 + Rational(5, 8))) + + 2*(-sqrt(5)/4 - Rational(1, 4))*log(sqrt(sqrt(5)/8 + Rational(5, 8))) + + 2*(-sqrt(5)/4 + Rational(1, 4))*log(Rational(1, 4) + sqrt(5)/4) + + Rational(486853480, 186374097) + pi*sqrt(2*sqrt(5) + 5)/2) + + Hooo = harmonic(no + po/qo) + Aooo = (-log(26) + 2*log(sin(pi*Rational(3, 13)))*cos(pi*Rational(54, 13)) + 2*log(sin(pi*Rational(4, 13)))*cos(pi*Rational(6, 13)) + + 2*log(sin(pi*Rational(6, 13)))*cos(pi*Rational(108, 13)) - 2*log(sin(pi*Rational(5, 13)))*cos(pi/13) + - 2*log(sin(pi/13))*cos(pi*Rational(5, 13)) + pi*cot(pi*Rational(4, 13))/2 + - 2*log(sin(pi*Rational(2, 13)))*cos(3*pi/13) + Rational(383693479, 125128080)) + + H = [Heee, Heeo, Heoe, Heoo, Hoee, Hoeo, Hooe, Hooo] + A = [Aeee, Aeeo, Aeoe, Aeoo, Aoee, Aoeo, Aooe, Aooo] + for h, a in zip(H, A): + e = expand_func(h).doit() + assert cancel(e/a) == 1 + assert abs(h.n() - a.n()) < 1e-12 + + +def test_harmonic_evalf(): + assert str(harmonic(1.5).evalf(n=10)) == '1.280372306' + assert str(harmonic(1.5, 2).evalf(n=10)) == '1.154576311' # issue 7443 + assert str(harmonic(4.0, -3).evalf(n=10)) == '100.0000000' + assert str(harmonic(7.0, 1.0).evalf(n=10)) == '2.592857143' + assert str(harmonic(1, pi).evalf(n=10)) == '1.000000000' + assert str(harmonic(2, pi).evalf(n=10)) == '1.113314732' + assert str(harmonic(1000.0, pi).evalf(n=10)) == '1.176241563' + assert str(harmonic(I).evalf(n=10)) == '0.6718659855 + 1.076674047*I' + assert str(harmonic(I, I).evalf(n=10)) == '-0.3970915266 + 1.9629689*I' + + assert harmonic(-1.0, 1).evalf() is S.NaN + assert harmonic(-2.0, 2.0).evalf() is S.NaN + +def test_harmonic_rewrite(): + from sympy.functions.elementary.piecewise import Piecewise + n = Symbol("n") + m = Symbol("m", integer=True, positive=True) + x1 = Symbol("x1", positive=True) + x2 = Symbol("x2", negative=True) + + assert harmonic(n).rewrite(digamma) == polygamma(0, n + 1) + EulerGamma + assert harmonic(n).rewrite(trigamma) == polygamma(0, n + 1) + EulerGamma + assert harmonic(n).rewrite(polygamma) == polygamma(0, n + 1) + EulerGamma + + assert harmonic(n,3).rewrite(polygamma) == polygamma(2, n + 1)/2 - polygamma(2, 1)/2 + assert isinstance(harmonic(n,m).rewrite(polygamma), Piecewise) + + assert expand_func(harmonic(n+4)) == harmonic(n) + 1/(n + 4) + 1/(n + 3) + 1/(n + 2) + 1/(n + 1) + assert expand_func(harmonic(n-4)) == harmonic(n) - 1/(n - 1) - 1/(n - 2) - 1/(n - 3) - 1/n + + assert harmonic(n, m).rewrite("tractable") == harmonic(n, m).rewrite(polygamma) + assert harmonic(n, x1).rewrite("tractable") == harmonic(n, x1) + assert harmonic(n, x1 + 1).rewrite("tractable") == zeta(x1 + 1) - zeta(x1 + 1, n + 1) + assert harmonic(n, x2).rewrite("tractable") == zeta(x2) - zeta(x2, n + 1) + + _k = Dummy("k") + assert harmonic(n).rewrite(Sum).dummy_eq(Sum(1/_k, (_k, 1, n))) + assert harmonic(n, m).rewrite(Sum).dummy_eq(Sum(_k**(-m), (_k, 1, n))) + + +def test_harmonic_calculus(): + y = Symbol("y", positive=True) + z = Symbol("z", negative=True) + assert harmonic(x, 1).limit(x, 0) == 0 + assert harmonic(x, y).limit(x, 0) == 0 + assert harmonic(x, 1).series(x, y, 2) == \ + harmonic(y) + (x - y)*zeta(2, y + 1) + O((x - y)**2, (x, y)) + assert limit(harmonic(x, y), x, oo) == harmonic(oo, y) + assert limit(harmonic(x, y + 1), x, oo) == zeta(y + 1) + assert limit(harmonic(x, y - 1), x, oo) == harmonic(oo, y - 1) + assert limit(harmonic(x, z), x, oo) == Limit(harmonic(x, z), x, oo, dir='-') + assert limit(harmonic(x, z + 1), x, oo) == oo + assert limit(harmonic(x, z + 2), x, oo) == harmonic(oo, z + 2) + assert limit(harmonic(x, z - 1), x, oo) == Limit(harmonic(x, z - 1), x, oo, dir='-') + + +def test_euler(): + assert euler(0) == 1 + assert euler(1) == 0 + assert euler(2) == -1 + assert euler(3) == 0 + assert euler(4) == 5 + assert euler(6) == -61 + assert euler(8) == 1385 + + assert euler(20, evaluate=False) != 370371188237525 + + n = Symbol('n', integer=True) + assert euler(n) != -1 + assert euler(n).subs(n, 2) == -1 + + assert euler(-1) == S.Pi / 2 + assert euler(-1, 1) == 2*log(2) + assert euler(-2).evalf() == (2*S.Catalan).evalf() + assert euler(-3).evalf() == (S.Pi**3 / 16).evalf() + assert str(euler(2.3).evalf(n=10)) == '-1.052850274' + assert str(euler(1.2, 3.4).evalf(n=10)) == '3.575613489' + assert str(euler(I).evalf(n=10)) == '1.248446443 - 0.7675445124*I' + assert str(euler(I, I).evalf(n=10)) == '0.04812930469 + 0.01052411008*I' + + assert euler(20).evalf() == 370371188237525.0 + assert euler(20, evaluate=False).evalf() == 370371188237525.0 + + assert euler(n).rewrite(Sum) == euler(n) + n = Symbol('n', integer=True, nonnegative=True) + assert euler(2*n + 1).rewrite(Sum) == 0 + _j = Dummy('j') + _k = Dummy('k') + assert euler(2*n).rewrite(Sum).dummy_eq( + I*Sum((-1)**_j*2**(-_k)*I**(-_k)*(-2*_j + _k)**(2*n + 1)* + binomial(_k, _j)/_k, (_j, 0, _k), (_k, 1, 2*n + 1))) + + +def test_euler_odd(): + n = Symbol('n', odd=True, positive=True) + assert euler(n) == 0 + n = Symbol('n', odd=True) + assert euler(n) != 0 + + +def test_euler_polynomials(): + assert euler(0, x) == 1 + assert euler(1, x) == x - S.Half + assert euler(2, x) == x**2 - x + assert euler(3, x) == x**3 - (3*x**2)/2 + Rational(1, 4) + m = Symbol('m') + assert isinstance(euler(m, x), euler) + from sympy.core.numbers import Float + A = Float('-0.46237208575048694923364757452876131e8') # from Maple + B = euler(19, S.Pi).evalf(32) + assert abs((A - B)/A) < 1e-31 + z = Float(0.1) + Float(0.2)*I + expected = Float(-3126.54721663773 ) + Float(565.736261497056) * I + assert abs(euler(13, z) - expected) < 1e-10 + + +def test_euler_polynomial_rewrite(): + m = Symbol('m') + A = euler(m, x).rewrite('Sum') + assert A.subs({m:3, x:5}).doit() == euler(3, 5) + + +def test_catalan(): + n = Symbol('n', integer=True) + m = Symbol('m', integer=True, positive=True) + k = Symbol('k', integer=True, nonnegative=True) + p = Symbol('p', nonnegative=True) + + catalans = [1, 1, 2, 5, 14, 42, 132, 429, 1430, 4862, 16796, 58786] + for i, c in enumerate(catalans): + assert catalan(i) == c + assert catalan(n).rewrite(factorial).subs(n, i) == c + assert catalan(n).rewrite(Product).subs(n, i).doit() == c + + assert unchanged(catalan, x) + assert catalan(2*x).rewrite(binomial) == binomial(4*x, 2*x)/(2*x + 1) + assert catalan(S.Half).rewrite(gamma) == 8/(3*pi) + assert catalan(S.Half).rewrite(factorial).rewrite(gamma) ==\ + 8 / (3 * pi) + assert catalan(3*x).rewrite(gamma) == 4**( + 3*x)*gamma(3*x + S.Half)/(sqrt(pi)*gamma(3*x + 2)) + assert catalan(x).rewrite(hyper) == hyper((-x + 1, -x), (2,), 1) + + assert catalan(n).rewrite(factorial) == factorial(2*n) / (factorial(n + 1) + * factorial(n)) + assert isinstance(catalan(n).rewrite(Product), catalan) + assert isinstance(catalan(m).rewrite(Product), Product) + + assert diff(catalan(x), x) == (polygamma( + 0, x + S.Half) - polygamma(0, x + 2) + log(4))*catalan(x) + + assert catalan(x).evalf() == catalan(x) + c = catalan(S.Half).evalf() + assert str(c) == '0.848826363156775' + c = catalan(I).evalf(3) + assert str((re(c), im(c))) == '(0.398, -0.0209)' + + # Assumptions + assert catalan(p).is_positive is True + assert catalan(k).is_integer is True + assert catalan(m+3).is_composite is True + + +def test_genocchi(): + genocchis = [0, -1, -1, 0, 1, 0, -3, 0, 17] + for n, g in enumerate(genocchis): + assert genocchi(n) == g + + m = Symbol('m', integer=True) + n = Symbol('n', integer=True, positive=True) + assert unchanged(genocchi, m) + assert genocchi(2*n + 1) == 0 + gn = 2 * (1 - 2**n) * bernoulli(n) + assert genocchi(n).rewrite(bernoulli).factor() == gn.factor() + gnx = 2 * (bernoulli(n, x) - 2**n * bernoulli(n, (x+1) / 2)) + assert genocchi(n, x).rewrite(bernoulli).factor() == gnx.factor() + assert genocchi(2 * n).is_odd + assert genocchi(2 * n).is_even is False + assert genocchi(2 * n + 1).is_even + assert genocchi(n).is_integer + assert genocchi(4 * n).is_positive + # these are the only 2 prime Genocchi numbers + assert genocchi(6, evaluate=False).is_prime == S(-3).is_prime + assert genocchi(8, evaluate=False).is_prime + assert genocchi(4 * n + 2).is_negative + assert genocchi(4 * n + 1).is_negative is False + assert genocchi(4 * n - 2).is_negative + + g0 = genocchi(0, evaluate=False) + assert g0.is_positive is False + assert g0.is_negative is False + assert g0.is_even is True + assert g0.is_odd is False + + assert genocchi(0, x) == 0 + assert genocchi(1, x) == -1 + assert genocchi(2, x) == 1 - 2*x + assert genocchi(3, x) == 3*x - 3*x**2 + assert genocchi(4, x) == -1 + 6*x**2 - 4*x**3 + y = Symbol("y") + assert genocchi(5, (x+y)**100) == -5*(x+y)**400 + 10*(x+y)**300 - 5*(x+y)**100 + + assert str(genocchi(5.0, 4.0).evalf(n=10)) == '-660.0000000' + assert str(genocchi(Rational(5, 4)).evalf(n=10)) == '-1.104286457' + assert str(genocchi(-2).evalf(n=10)) == '3.606170709' + assert str(genocchi(1.3, 3.7).evalf(n=10)) == '-1.847375373' + assert str(genocchi(I, 1.0).evalf(n=10)) == '-0.3161917278 - 1.45311955*I' + + n = Symbol('n') + assert genocchi(n, x).rewrite(dirichlet_eta) == -2*n * dirichlet_eta(1-n, x) + + +def test_andre(): + nums = [1, 1, 1, 2, 5, 16, 61, 272, 1385, 7936, 50521] + for n, a in enumerate(nums): + assert andre(n) == a + assert andre(S.Infinity) == S.Infinity + assert andre(-1) == -log(2) + assert andre(-2) == -2*S.Catalan + assert andre(-3) == 3*zeta(3)/16 + assert andre(-5) == -15*zeta(5)/256 + # In fact andre(-2*n) is related to the Dirichlet *beta* function + # at 2*n, but SymPy doesn't implement that (or general L-functions) + assert unchanged(andre, -4) + + n = Symbol('n', integer=True, nonnegative=True) + assert unchanged(andre, n) + assert andre(n).is_integer is True + assert andre(n).is_positive is True + + assert str(andre(10, evaluate=False).evalf(n=10)) == '50521.00000' + assert str(andre(-1, evaluate=False).evalf(n=10)) == '-0.6931471806' + assert str(andre(-2, evaluate=False).evalf(n=10)) == '-1.831931188' + assert str(andre(-4, evaluate=False).evalf(n=10)) == '1.977889103' + assert str(andre(I, evaluate=False).evalf(n=10)) == '2.378417833 + 0.6343322845*I' + + assert andre(x).rewrite(polylog) == \ + (-I)**(x+1) * polylog(-x, I) + I**(x+1) * polylog(-x, -I) + assert andre(x).rewrite(zeta) == \ + 2 * gamma(x+1) / (2*pi)**(x+1) * \ + (zeta(x+1, Rational(1,4)) - cos(pi*x) * zeta(x+1, Rational(3,4))) + + +@nocache_fail +def test_partition(): + partition_nums = [1, 1, 2, 3, 5, 7, 11, 15, 22] + for n, p in enumerate(partition_nums): + assert partition(n) == p + + x = Symbol('x') + y = Symbol('y', real=True) + m = Symbol('m', integer=True) + n = Symbol('n', integer=True, negative=True) + p = Symbol('p', integer=True, nonnegative=True) + assert partition(m).is_integer + assert not partition(m).is_negative + assert partition(m).is_nonnegative + assert partition(n).is_zero + assert partition(p).is_positive + assert partition(x).subs(x, 7) == 15 + assert partition(y).subs(y, 8) == 22 + raises(TypeError, lambda: partition(Rational(5, 4))) + assert partition(9, evaluate=False) % 5 == 0 + assert partition(5*m + 4) % 5 == 0 + assert partition(47, evaluate=False) % 7 == 0 + assert partition(7*m + 5) % 7 == 0 + assert partition(50, evaluate=False) % 11 == 0 + assert partition(11*m + 6) % 11 == 0 + + +def test_divisor_sigma(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: divisor_sigma(m)) + raises(TypeError, lambda: divisor_sigma(4.5)) + raises(TypeError, lambda: divisor_sigma(1, m)) + raises(TypeError, lambda: divisor_sigma(1, 4.5)) + m = Symbol('m', positive=False) + raises(ValueError, lambda: divisor_sigma(m)) + raises(ValueError, lambda: divisor_sigma(0)) + m = Symbol('m', negative=True) + raises(ValueError, lambda: divisor_sigma(1, m)) + raises(ValueError, lambda: divisor_sigma(1, -1)) + + # special case + p = Symbol('p', prime=True) + k = Symbol('k', integer=True) + assert divisor_sigma(p, 1) == p + 1 + assert divisor_sigma(p, k) == p**k + 1 + + # property + n = Symbol('n', integer=True, positive=True) + assert divisor_sigma(n).is_integer is True + assert divisor_sigma(n).is_positive is True + + # symbolic + k = Symbol('k', integer=True, zero=False) + assert divisor_sigma(4, k) == 2**(2*k) + 2**k + 1 + assert divisor_sigma(6, k) == (2**k + 1) * (3**k + 1) + + # Integer + assert divisor_sigma(23450) == 50592 + assert divisor_sigma(23450, 0) == 24 + assert divisor_sigma(23450, 1) == 50592 + assert divisor_sigma(23450, 2) == 730747500 + assert divisor_sigma(23450, 3) == 14666785333344 + + +def test_udivisor_sigma(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: udivisor_sigma(m)) + raises(TypeError, lambda: udivisor_sigma(4.5)) + raises(TypeError, lambda: udivisor_sigma(1, m)) + raises(TypeError, lambda: udivisor_sigma(1, 4.5)) + m = Symbol('m', positive=False) + raises(ValueError, lambda: udivisor_sigma(m)) + raises(ValueError, lambda: udivisor_sigma(0)) + m = Symbol('m', negative=True) + raises(ValueError, lambda: udivisor_sigma(1, m)) + raises(ValueError, lambda: udivisor_sigma(1, -1)) + + # special case + p = Symbol('p', prime=True) + k = Symbol('k', integer=True) + assert udivisor_sigma(p, 1) == p + 1 + assert udivisor_sigma(p, k) == p**k + 1 + + # property + n = Symbol('n', integer=True, positive=True) + assert udivisor_sigma(n).is_integer is True + assert udivisor_sigma(n).is_positive is True + + # Integer + A034444 = [1, 2, 2, 2, 2, 4, 2, 2, 2, 4, 2, 4, 2, 4, 4, 2, 2, 4, 2, 4, + 4, 4, 2, 4, 2, 4, 2, 4, 2, 8, 2, 2, 4, 4, 4, 4, 2, 4, 4, 4, + 2, 8, 2, 4, 4, 4, 2, 4, 2, 4, 4, 4, 2, 4, 4, 4, 4, 4, 2, 8] + for n, val in enumerate(A034444, 1): + assert udivisor_sigma(n, 0) == val + A034448 = [1, 3, 4, 5, 6, 12, 8, 9, 10, 18, 12, 20, 14, 24, 24, 17, 18, + 30, 20, 30, 32, 36, 24, 36, 26, 42, 28, 40, 30, 72, 32, 33, + 48, 54, 48, 50, 38, 60, 56, 54, 42, 96, 44, 60, 60, 72, 48] + for n, val in enumerate(A034448, 1): + assert udivisor_sigma(n, 1) == val + A034676 = [1, 5, 10, 17, 26, 50, 50, 65, 82, 130, 122, 170, 170, 250, + 260, 257, 290, 410, 362, 442, 500, 610, 530, 650, 626, 850, + 730, 850, 842, 1300, 962, 1025, 1220, 1450, 1300, 1394, 1370] + for n, val in enumerate(A034676, 1): + assert udivisor_sigma(n, 2) == val + + +def test_legendre_symbol(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: legendre_symbol(m, 3)) + raises(TypeError, lambda: legendre_symbol(4.5, 3)) + raises(TypeError, lambda: legendre_symbol(1, m)) + raises(TypeError, lambda: legendre_symbol(1, 4.5)) + m = Symbol('m', prime=False) + raises(ValueError, lambda: legendre_symbol(1, m)) + raises(ValueError, lambda: legendre_symbol(1, 6)) + m = Symbol('m', odd=False) + raises(ValueError, lambda: legendre_symbol(1, m)) + raises(ValueError, lambda: legendre_symbol(1, 2)) + + # special case + p = Symbol('p', prime=True) + k = Symbol('k', integer=True) + assert legendre_symbol(p*k, p) == 0 + assert legendre_symbol(1, p) == 1 + + # property + n = Symbol('n') + m = Symbol('m') + assert legendre_symbol(m, n).is_integer is True + assert legendre_symbol(m, n).is_prime is False + + # Integer + assert legendre_symbol(5, 11) == 1 + assert legendre_symbol(25, 41) == 1 + assert legendre_symbol(67, 101) == -1 + assert legendre_symbol(0, 13) == 0 + assert legendre_symbol(9, 3) == 0 + + +def test_jacobi_symbol(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: jacobi_symbol(m, 3)) + raises(TypeError, lambda: jacobi_symbol(4.5, 3)) + raises(TypeError, lambda: jacobi_symbol(1, m)) + raises(TypeError, lambda: jacobi_symbol(1, 4.5)) + m = Symbol('m', positive=False) + raises(ValueError, lambda: jacobi_symbol(1, m)) + raises(ValueError, lambda: jacobi_symbol(1, -6)) + m = Symbol('m', odd=False) + raises(ValueError, lambda: jacobi_symbol(1, m)) + raises(ValueError, lambda: jacobi_symbol(1, 2)) + + # special case + p = Symbol('p', integer=True) + k = Symbol('k', integer=True) + assert jacobi_symbol(p*k, p) == 0 + assert jacobi_symbol(1, p) == 1 + assert jacobi_symbol(1, 1) == 1 + assert jacobi_symbol(0, 1) == 1 + + # property + n = Symbol('n') + m = Symbol('m') + assert jacobi_symbol(m, n).is_integer is True + assert jacobi_symbol(m, n).is_prime is False + + # Integer + assert jacobi_symbol(25, 41) == 1 + assert jacobi_symbol(-23, 83) == -1 + assert jacobi_symbol(3, 9) == 0 + assert jacobi_symbol(42, 97) == -1 + assert jacobi_symbol(3, 5) == -1 + assert jacobi_symbol(7, 9) == 1 + assert jacobi_symbol(0, 3) == 0 + assert jacobi_symbol(0, 1) == 1 + assert jacobi_symbol(2, 1) == 1 + assert jacobi_symbol(1, 3) == 1 + + +def test_kronecker_symbol(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: kronecker_symbol(m, 3)) + raises(TypeError, lambda: kronecker_symbol(4.5, 3)) + raises(TypeError, lambda: kronecker_symbol(1, m)) + raises(TypeError, lambda: kronecker_symbol(1, 4.5)) + + # special case + p = Symbol('p', integer=True) + assert kronecker_symbol(1, p) == 1 + assert kronecker_symbol(1, 1) == 1 + assert kronecker_symbol(0, 1) == 1 + + # property + n = Symbol('n') + m = Symbol('m') + assert kronecker_symbol(m, n).is_integer is True + assert kronecker_symbol(m, n).is_prime is False + + # Integer + for n in range(3, 10, 2): + for a in range(-n, n): + val = kronecker_symbol(a, n) + assert val == jacobi_symbol(a, n) + minus = kronecker_symbol(a, -n) + if a < 0: + assert -minus == val + else: + assert minus == val + even = kronecker_symbol(a, 2 * n) + if a % 2 == 0: + assert even == 0 + elif a % 8 in [1, 7]: + assert even == val + else: + assert -even == val + assert kronecker_symbol(1, 0) == kronecker_symbol(-1, 0) == 1 + assert kronecker_symbol(0, 0) == 0 + + +def test_mobius(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: mobius(m)) + raises(TypeError, lambda: mobius(4.5)) + m = Symbol('m', positive=False) + raises(ValueError, lambda: mobius(m)) + raises(ValueError, lambda: mobius(-3)) + + # special case + p = Symbol('p', prime=True) + assert mobius(p) == -1 + + # property + n = Symbol('n', integer=True, positive=True) + assert mobius(n).is_integer is True + assert mobius(n).is_prime is False + + # symbolic + n = Symbol('n', integer=True, positive=True) + k = Symbol('k', integer=True, positive=True) + assert mobius(n**2) == 0 + assert mobius(4*n) == 0 + assert isinstance(mobius(n**k), mobius) + assert mobius(n**(k+1)) == 0 + assert isinstance(mobius(3**k), mobius) + assert mobius(3**(k+1)) == 0 + m = Symbol('m') + assert isinstance(mobius(4*m), mobius) + + # Integer + assert mobius(13*7) == 1 + assert mobius(1) == 1 + assert mobius(13*7*5) == -1 + assert mobius(13**2) == 0 + A008683 = [1, -1, -1, 0, -1, 1, -1, 0, 0, 1, -1, 0, -1, 1, 1, 0, -1, 0, + -1, 0, 1, 1, -1, 0, 0, 1, 0, 0, -1, -1, -1, 0, 1, 1, 1, 0, -1, + 1, 1, 0, -1, -1, -1, 0, 0, 1, -1, 0, 0, 0, 1, 0, -1, 0, 1, 0] + for n, val in enumerate(A008683, 1): + assert mobius(n) == val + + +def test_primenu(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: primenu(m)) + raises(TypeError, lambda: primenu(4.5)) + m = Symbol('m', positive=False) + raises(ValueError, lambda: primenu(m)) + raises(ValueError, lambda: primenu(0)) + + # special case + p = Symbol('p', prime=True) + assert primenu(p) == 1 + + # property + n = Symbol('n', integer=True, positive=True) + assert primenu(n).is_integer is True + assert primenu(n).is_nonnegative is True + + # Integer + assert primenu(7*13) == 2 + assert primenu(2*17*19) == 3 + assert primenu(2**3 * 17 * 19**2) == 3 + A001221 = [0, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 2, 1, 1, 2, + 1, 2, 2, 2, 1, 2, 1, 2, 1, 2, 1, 3, 1, 1, 2, 2, 2, 2] + for n, val in enumerate(A001221, 1): + assert primenu(n) == val + + +def test_primeomega(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: primeomega(m)) + raises(TypeError, lambda: primeomega(4.5)) + m = Symbol('m', positive=False) + raises(ValueError, lambda: primeomega(m)) + raises(ValueError, lambda: primeomega(0)) + + # special case + p = Symbol('p', prime=True) + assert primeomega(p) == 1 + + # property + n = Symbol('n', integer=True, positive=True) + assert primeomega(n).is_integer is True + assert primeomega(n).is_nonnegative is True + + # Integer + assert primeomega(7*13) == 2 + assert primeomega(2*17*19) == 3 + assert primeomega(2**3 * 17 * 19**2) == 6 + A001222 = [0, 1, 1, 2, 1, 2, 1, 3, 2, 2, 1, 3, 1, 2, 2, 4, 1, 3, + 1, 3, 2, 2, 1, 4, 2, 2, 3, 3, 1, 3, 1, 5, 2, 2, 2, 4] + for n, val in enumerate(A001222, 1): + assert primeomega(n) == val + + +def test_totient(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: totient(m)) + raises(TypeError, lambda: totient(4.5)) + m = Symbol('m', positive=False) + raises(ValueError, lambda: totient(m)) + raises(ValueError, lambda: totient(0)) + + # special case + p = Symbol('p', prime=True) + assert totient(p) == p - 1 + + # property + n = Symbol('n', integer=True, positive=True) + assert totient(n).is_integer is True + assert totient(n).is_positive is True + + # Integer + assert totient(7*13) == totient(factorint(7*13)) == (7-1)*(13-1) + assert totient(2*17*19) == totient(factorint(2*17*19)) == (17-1)*(19-1) + assert totient(2**3 * 17 * 19**2) == totient({2: 3, 17: 1, 19: 2}) == 2**2 * (17-1) * 19*(19-1) + A000010 = [1, 1, 2, 2, 4, 2, 6, 4, 6, 4, 10, 4, 12, 6, 8, 8, 16, + 6, 18, 8, 12, 10, 22, 8, 20, 12, 18, 12, 28, 8, 30, 16, + 20, 16, 24, 12, 36, 18, 24, 16, 40, 12, 42, 20, 24, 22] + for n, val in enumerate(A000010, 1): + assert totient(n) == val + + +def test_reduced_totient(): + # error + m = Symbol('m', integer=False) + raises(TypeError, lambda: reduced_totient(m)) + raises(TypeError, lambda: reduced_totient(4.5)) + m = Symbol('m', positive=False) + raises(ValueError, lambda: reduced_totient(m)) + raises(ValueError, lambda: reduced_totient(0)) + + # special case + p = Symbol('p', prime=True) + assert reduced_totient(p) == p - 1 + + # property + n = Symbol('n', integer=True, positive=True) + assert reduced_totient(n).is_integer is True + assert reduced_totient(n).is_positive is True + + # Integer + assert reduced_totient(7*13) == reduced_totient(factorint(7*13)) == 12 + assert reduced_totient(2*17*19) == reduced_totient(factorint(2*17*19)) == 144 + assert reduced_totient(2**2 * 11) == reduced_totient({2: 2, 11: 1}) == 10 + assert reduced_totient(2**3 * 17 * 19**2) == reduced_totient({2: 3, 17: 1, 19: 2}) == 2736 + A002322 = [1, 1, 2, 2, 4, 2, 6, 2, 6, 4, 10, 2, 12, 6, 4, 4, 16, 6, + 18, 4, 6, 10, 22, 2, 20, 12, 18, 6, 28, 4, 30, 8, 10, 16, + 12, 6, 36, 18, 12, 4, 40, 6, 42, 10, 12, 22, 46, 4, 42] + for n, val in enumerate(A002322, 1): + assert reduced_totient(n) == val + + +def test_primepi(): + # error + z = Symbol('z', real=False) + raises(TypeError, lambda: primepi(z)) + raises(TypeError, lambda: primepi(I)) + + # property + n = Symbol('n', integer=True, positive=True) + assert primepi(n).is_integer is True + assert primepi(n).is_nonnegative is True + + # infinity + assert primepi(oo) == oo + assert primepi(-oo) == 0 + + # symbol + x = Symbol('x') + assert isinstance(primepi(x), primepi) + + # Integer + assert primepi(0) == 0 + A000720 = [0, 1, 2, 2, 3, 3, 4, 4, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 8, + 8, 8, 8, 9, 9, 9, 9, 9, 9, 10, 10, 11, 11, 11, 11, 11, 11, + 12, 12, 12, 12, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15] + for n, val in enumerate(A000720, 1): + assert primepi(n) == primepi(n + 0.5) == val + + +def test__nT(): + assert [_nT(i, j) for i in range(5) for j in range(i + 2)] == [ + 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 2, 1, 1, 0] + check = [_nT(10, i) for i in range(11)] + assert check == [0, 1, 5, 8, 9, 7, 5, 3, 2, 1, 1] + assert all(type(i) is int for i in check) + assert _nT(10, 5) == 7 + assert _nT(100, 98) == 2 + assert _nT(100, 100) == 1 + assert _nT(10, 3) == 8 + + +def test_nC_nP_nT(): + from sympy.utilities.iterables import ( + multiset_permutations, multiset_combinations, multiset_partitions, + partitions, subsets, permutations) + from sympy.functions.combinatorial.numbers import ( + nP, nC, nT, stirling, _stirling1, _stirling2, _multiset_histogram, _AOP_product) + + from sympy.combinatorics.permutations import Permutation + from sympy.core.random import choice + + c = string.ascii_lowercase + for i in range(100): + s = ''.join(choice(c) for i in range(7)) + u = len(s) == len(set(s)) + try: + tot = 0 + for i in range(8): + check = nP(s, i) + tot += check + assert len(list(multiset_permutations(s, i))) == check + if u: + assert nP(len(s), i) == check + assert nP(s) == tot + except AssertionError: + print(s, i, 'failed perm test') + raise ValueError() + + for i in range(100): + s = ''.join(choice(c) for i in range(7)) + u = len(s) == len(set(s)) + try: + tot = 0 + for i in range(8): + check = nC(s, i) + tot += check + assert len(list(multiset_combinations(s, i))) == check + if u: + assert nC(len(s), i) == check + assert nC(s) == tot + if u: + assert nC(len(s)) == tot + except AssertionError: + print(s, i, 'failed combo test') + raise ValueError() + + for i in range(1, 10): + tot = 0 + for j in range(1, i + 2): + check = nT(i, j) + assert check.is_Integer + tot += check + assert sum(1 for p in partitions(i, j, size=True) if p[0] == j) == check + assert nT(i) == tot + + for i in range(1, 10): + tot = 0 + for j in range(1, i + 2): + check = nT(range(i), j) + tot += check + assert len(list(multiset_partitions(list(range(i)), j))) == check + assert nT(range(i)) == tot + + for i in range(100): + s = ''.join(choice(c) for i in range(7)) + u = len(s) == len(set(s)) + try: + tot = 0 + for i in range(1, 8): + check = nT(s, i) + tot += check + assert len(list(multiset_partitions(s, i))) == check + if u: + assert nT(range(len(s)), i) == check + if u: + assert nT(range(len(s))) == tot + assert nT(s) == tot + except AssertionError: + print(s, i, 'failed partition test') + raise ValueError() + + # tests for Stirling numbers of the first kind that are not tested in the + # above + assert [stirling(9, i, kind=1) for i in range(11)] == [ + 0, 40320, 109584, 118124, 67284, 22449, 4536, 546, 36, 1, 0] + perms = list(permutations(range(4))) + assert [sum(1 for p in perms if Permutation(p).cycles == i) + for i in range(5)] == [0, 6, 11, 6, 1] == [ + stirling(4, i, kind=1) for i in range(5)] + # http://oeis.org/A008275 + assert [stirling(n, k, signed=1) + for n in range(10) for k in range(1, n + 1)] == [ + 1, -1, + 1, 2, -3, + 1, -6, 11, -6, + 1, 24, -50, 35, -10, + 1, -120, 274, -225, 85, -15, + 1, 720, -1764, 1624, -735, 175, -21, + 1, -5040, 13068, -13132, 6769, -1960, 322, -28, + 1, 40320, -109584, 118124, -67284, 22449, -4536, 546, -36, 1] + # https://en.wikipedia.org/wiki/Stirling_numbers_of_the_first_kind + assert [stirling(n, k, kind=1) + for n in range(10) for k in range(n+1)] == [ + 1, + 0, 1, + 0, 1, 1, + 0, 2, 3, 1, + 0, 6, 11, 6, 1, + 0, 24, 50, 35, 10, 1, + 0, 120, 274, 225, 85, 15, 1, + 0, 720, 1764, 1624, 735, 175, 21, 1, + 0, 5040, 13068, 13132, 6769, 1960, 322, 28, 1, + 0, 40320, 109584, 118124, 67284, 22449, 4536, 546, 36, 1] + # https://en.wikipedia.org/wiki/Stirling_numbers_of_the_second_kind + assert [stirling(n, k, kind=2) + for n in range(10) for k in range(n+1)] == [ + 1, + 0, 1, + 0, 1, 1, + 0, 1, 3, 1, + 0, 1, 7, 6, 1, + 0, 1, 15, 25, 10, 1, + 0, 1, 31, 90, 65, 15, 1, + 0, 1, 63, 301, 350, 140, 21, 1, + 0, 1, 127, 966, 1701, 1050, 266, 28, 1, + 0, 1, 255, 3025, 7770, 6951, 2646, 462, 36, 1] + assert stirling(3, 4, kind=1) == stirling(3, 4, kind=1) == 0 + raises(ValueError, lambda: stirling(-2, 2)) + + # Assertion that the return type is SymPy Integer. + assert isinstance(_stirling1(6, 3), Integer) + assert isinstance(_stirling2(6, 3), Integer) + + def delta(p): + if len(p) == 1: + return oo + return min(abs(i[0] - i[1]) for i in subsets(p, 2)) + parts = multiset_partitions(range(5), 3) + d = 2 + assert (sum(1 for p in parts if all(delta(i) >= d for i in p)) == + stirling(5, 3, d=d) == 7) + + # other coverage tests + assert nC('abb', 2) == nC('aab', 2) == 2 + assert nP(3, 3, replacement=True) == nP('aabc', 3, replacement=True) == 27 + assert nP(3, 4) == 0 + assert nP('aabc', 5) == 0 + assert nC(4, 2, replacement=True) == nC('abcdd', 2, replacement=True) == \ + len(list(multiset_combinations('aabbccdd', 2))) == 10 + assert nC('abcdd') == sum(nC('abcdd', i) for i in range(6)) == 24 + assert nC(list('abcdd'), 4) == 4 + assert nT('aaaa') == nT(4) == len(list(partitions(4))) == 5 + assert nT('aaab') == len(list(multiset_partitions('aaab'))) == 7 + assert nC('aabb'*3, 3) == 4 # aaa, bbb, abb, baa + assert dict(_AOP_product((4,1,1,1))) == { + 0: 1, 1: 4, 2: 7, 3: 8, 4: 8, 5: 7, 6: 4, 7: 1} + # the following was the first t that showed a problem in a previous form of + # the function, so it's not as random as it may appear + t = (3, 9, 4, 6, 6, 5, 5, 2, 10, 4) + assert sum(_AOP_product(t)[i] for i in range(55)) == 58212000 + raises(ValueError, lambda: _multiset_histogram({1:'a'})) + + +def test_PR_14617(): + from sympy.functions.combinatorial.numbers import nT + for n in (0, []): + for k in (-1, 0, 1): + if k == 0: + assert nT(n, k) == 1 + else: + assert nT(n, k) == 0 + + +def test_issue_8496(): + n = Symbol("n") + k = Symbol("k") + + raises(TypeError, lambda: catalan(n, k)) + + +def test_issue_8601(): + n = Symbol('n', integer=True, negative=True) + + assert catalan(n - 1) is S.Zero + assert catalan(Rational(-1, 2)) is S.ComplexInfinity + assert catalan(-S.One) == Rational(-1, 2) + c1 = catalan(-5.6).evalf() + assert str(c1) == '6.93334070531408e-5' + c2 = catalan(-35.4).evalf() + assert str(c2) == '-4.14189164517449e-24' + + +def test_motzkin(): + assert motzkin.is_motzkin(4) == True + assert motzkin.is_motzkin(9) == True + assert motzkin.is_motzkin(10) == False + assert motzkin.find_motzkin_numbers_in_range(10,200) == [21, 51, 127] + assert motzkin.find_motzkin_numbers_in_range(10,400) == [21, 51, 127, 323] + assert motzkin.find_motzkin_numbers_in_range(10,1600) == [21, 51, 127, 323, 835] + assert motzkin.find_first_n_motzkins(5) == [1, 1, 2, 4, 9] + assert motzkin.find_first_n_motzkins(7) == [1, 1, 2, 4, 9, 21, 51] + assert motzkin.find_first_n_motzkins(10) == [1, 1, 2, 4, 9, 21, 51, 127, 323, 835] + raises(ValueError, lambda: motzkin.eval(77.58)) + raises(ValueError, lambda: motzkin.eval(-8)) + raises(ValueError, lambda: motzkin.find_motzkin_numbers_in_range(-2,7)) + raises(ValueError, lambda: motzkin.find_motzkin_numbers_in_range(13,7)) + raises(ValueError, lambda: motzkin.find_first_n_motzkins(112.8)) + + +def test_nD_derangements(): + from sympy.utilities.iterables import (partitions, multiset, + multiset_derangements, multiset_permutations) + from sympy.functions.combinatorial.numbers import nD + + got = [] + for i in partitions(8, k=4): + s = [] + it = 0 + for k, v in i.items(): + for i in range(v): + s.extend([it]*k) + it += 1 + ms = multiset(s) + c1 = sum(1 for i in multiset_permutations(s) if + all(i != j for i, j in zip(i, s))) + assert c1 == nD(ms) == nD(ms, 0) == nD(ms, 1) + v = [tuple(i) for i in multiset_derangements(s)] + c2 = len(v) + assert c2 == len(set(v)) + assert c1 == c2 + got.append(c1) + assert got == [1, 4, 6, 12, 24, 24, 61, 126, 315, 780, 297, 772, + 2033, 5430, 14833] + + assert nD('1112233456', brute=True) == nD('1112233456') == 16356 + assert nD('') == nD([]) == nD({}) == 0 + assert nD({1: 0}) == 0 + raises(ValueError, lambda: nD({1: -1})) + assert nD('112') == 0 + assert nD(i='112') == 0 + assert [nD(n=i) for i in range(6)] == [0, 0, 1, 2, 9, 44] + assert nD((i for i in range(4))) == nD('0123') == 9 + assert nD(m=(i for i in range(4))) == 3 + assert nD(m={0: 1, 1: 1, 2: 1, 3: 1}) == 3 + assert nD(m=[0, 1, 2, 3]) == 3 + raises(TypeError, lambda: nD(m=0)) + raises(TypeError, lambda: nD(-1)) + assert nD({-1: 1, -2: 1}) == 1 + assert nD(m={0: 3}) == 0 + raises(ValueError, lambda: nD(i='123', n=3)) + raises(ValueError, lambda: nD(i='123', m=(1,2))) + raises(ValueError, lambda: nD(n=0, m=(1,2))) + raises(ValueError, lambda: nD({1: -1})) + raises(ValueError, lambda: nD(m={-1: 1, 2: 1})) + raises(ValueError, lambda: nD(m={1: -1, 2: 1})) + raises(ValueError, lambda: nD(m=[-1, 2])) + raises(TypeError, lambda: nD({1: x})) + raises(TypeError, lambda: nD(m={1: x})) + raises(TypeError, lambda: nD(m={x: 1})) + + +def test_deprecated_ntheory_symbolic_functions(): + from sympy.testing.pytest import warns_deprecated_sympy + + with warns_deprecated_sympy(): + assert not carmichael.is_carmichael(3) + with warns_deprecated_sympy(): + assert carmichael.find_carmichael_numbers_in_range(10, 20) == [] + with warns_deprecated_sympy(): + assert carmichael.find_first_n_carmichaels(1) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..78034e72ef2ed722c3ae685a87cf4df618a982b0 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/__init__.py @@ -0,0 +1 @@ +# Stub __init__.py for sympy.functions.elementary diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/_trigonometric_special.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/_trigonometric_special.py new file mode 100644 index 0000000000000000000000000000000000000000..fdf8c9d06241b46e791afe76836ea33e6d4fb1c8 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/_trigonometric_special.py @@ -0,0 +1,261 @@ +r"""A module for special angle formulas for trigonometric functions + +TODO +==== + +This module should be developed in the future to contain direct square root +representation of + +.. math + F(\frac{n}{m} \pi) + +for every + +- $m \in \{ 3, 5, 17, 257, 65537 \}$ +- $n \in \mathbb{N}$, $0 \le n < m$ +- $F \in \{\sin, \cos, \tan, \csc, \sec, \cot\}$ + +Without multi-step rewrites +(e.g. $\tan \to \cos/\sin \to \cos/\sqrt \to \ sqrt$) +or using chebyshev identities +(e.g. $\cos \to \cos + \cos^2 + \cdots \to \sqrt{} + \sqrt{}^2 + \cdots $), +which are trivial to implement in sympy, +and had used to give overly complicated expressions. + +The reference can be found below, if anyone may need help implementing them. + +References +========== + +.. [*] Gottlieb, Christian. (1999). The Simple and straightforward construction + of the regular 257-gon. The Mathematical Intelligencer. 21. 31-37. + 10.1007/BF03024829. +.. [*] https://resources.wolframcloud.com/FunctionRepository/resources/Cos2PiOverFermatPrime +""" +from __future__ import annotations +from typing import Callable +from functools import reduce +from sympy.core.expr import Expr +from sympy.core.singleton import S +from sympy.core.intfunc import igcdex +from sympy.core.numbers import Integer +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.core.cache import cacheit + + +def migcdex(*x: int) -> tuple[tuple[int, ...], int]: + r"""Compute extended gcd for multiple integers. + + Explanation + =========== + + Given the integers $x_1, \cdots, x_n$ and + an extended gcd for multiple arguments are defined as a solution + $(y_1, \cdots, y_n), g$ for the diophantine equation + $x_1 y_1 + \cdots + x_n y_n = g$ such that + $g = \gcd(x_1, \cdots, x_n)$. + + Examples + ======== + + >>> from sympy.functions.elementary._trigonometric_special import migcdex + >>> migcdex() + ((), 0) + >>> migcdex(4) + ((1,), 4) + >>> migcdex(4, 6) + ((-1, 1), 2) + >>> migcdex(6, 10, 15) + ((1, 1, -1), 1) + """ + if not x: + return (), 0 + + if len(x) == 1: + return (1,), x[0] + + if len(x) == 2: + u, v, h = igcdex(x[0], x[1]) + return (u, v), h + + y, g = migcdex(*x[1:]) + u, v, h = igcdex(x[0], g) + return (u, *(v * i for i in y)), h + + +def ipartfrac(*denoms: int) -> tuple[int, ...]: + r"""Compute the partial fraction decomposition. + + Explanation + =========== + + Given a rational number $\frac{1}{q_1 \cdots q_n}$ where all + $q_1, \cdots, q_n$ are pairwise coprime, + + A partial fraction decomposition is defined as + + .. math:: + \frac{1}{q_1 \cdots q_n} = \frac{p_1}{q_1} + \cdots + \frac{p_n}{q_n} + + And it can be derived from solving the following diophantine equation for + the $p_1, \cdots, p_n$ + + .. math:: + 1 = p_1 \prod_{i \ne 1}q_i + \cdots + p_n \prod_{i \ne n}q_i + + Where $q_1, \cdots, q_n$ being pairwise coprime implies + $\gcd(\prod_{i \ne 1}q_i, \cdots, \prod_{i \ne n}q_i) = 1$, + which guarantees the existence of the solution. + + It is sufficient to compute partial fraction decomposition only + for numerator $1$ because partial fraction decomposition for any + $\frac{n}{q_1 \cdots q_n}$ can be easily computed by multiplying + the result by $n$ afterwards. + + Parameters + ========== + + denoms : int + The pairwise coprime integer denominators $q_i$ which defines the + rational number $\frac{1}{q_1 \cdots q_n}$ + + Returns + ======= + + tuple[int, ...] + The list of numerators which semantically corresponds to $p_i$ of the + partial fraction decomposition + $\frac{1}{q_1 \cdots q_n} = \frac{p_1}{q_1} + \cdots + \frac{p_n}{q_n}$ + + Examples + ======== + + >>> from sympy import Rational, Mul + >>> from sympy.functions.elementary._trigonometric_special import ipartfrac + + >>> denoms = 2, 3, 5 + >>> numers = ipartfrac(2, 3, 5) + >>> numers + (1, 7, -14) + + >>> Rational(1, Mul(*denoms)) + 1/30 + >>> out = 0 + >>> for n, d in zip(numers, denoms): + ... out += Rational(n, d) + >>> out + 1/30 + """ + if not denoms: + return () + + def mul(x: int, y: int) -> int: + return x * y + + denom = reduce(mul, denoms) + a = [denom // x for x in denoms] + h, _ = migcdex(*a) + return h + + +def fermat_coords(n: int) -> list[int] | None: + """If n can be factored in terms of Fermat primes with + multiplicity of each being 1, return those primes, else + None + """ + primes = [] + for p in [3, 5, 17, 257, 65537]: + quotient, remainder = divmod(n, p) + if remainder == 0: + n = quotient + primes.append(p) + if n == 1: + return primes + return None + + +@cacheit +def cos_3() -> Expr: + r"""Computes $\cos \frac{\pi}{3}$ in square roots""" + return S.Half + + +@cacheit +def cos_5() -> Expr: + r"""Computes $\cos \frac{\pi}{5}$ in square roots""" + return (sqrt(5) + 1) / 4 + + +@cacheit +def cos_17() -> Expr: + r"""Computes $\cos \frac{\pi}{17}$ in square roots""" + return sqrt( + (15 + sqrt(17)) / 32 + sqrt(2) * (sqrt(17 - sqrt(17)) + + sqrt(sqrt(2) * (-8 * sqrt(17 + sqrt(17)) - (1 - sqrt(17)) + * sqrt(17 - sqrt(17))) + 6 * sqrt(17) + 34)) / 32) + + +@cacheit +def cos_257() -> Expr: + r"""Computes $\cos \frac{\pi}{257}$ in square roots + + References + ========== + + .. [*] https://math.stackexchange.com/questions/516142/how-does-cos2-pi-257-look-like-in-real-radicals + .. [*] https://r-knott.surrey.ac.uk/Fibonacci/simpleTrig.html + """ + def f1(a: Expr, b: Expr) -> tuple[Expr, Expr]: + return (a + sqrt(a**2 + b)) / 2, (a - sqrt(a**2 + b)) / 2 + + def f2(a: Expr, b: Expr) -> Expr: + return (a - sqrt(a**2 + b))/2 + + t1, t2 = f1(S.NegativeOne, Integer(256)) + z1, z3 = f1(t1, Integer(64)) + z2, z4 = f1(t2, Integer(64)) + y1, y5 = f1(z1, 4*(5 + t1 + 2*z1)) + y6, y2 = f1(z2, 4*(5 + t2 + 2*z2)) + y3, y7 = f1(z3, 4*(5 + t1 + 2*z3)) + y8, y4 = f1(z4, 4*(5 + t2 + 2*z4)) + x1, x9 = f1(y1, -4*(t1 + y1 + y3 + 2*y6)) + x2, x10 = f1(y2, -4*(t2 + y2 + y4 + 2*y7)) + x3, x11 = f1(y3, -4*(t1 + y3 + y5 + 2*y8)) + x4, x12 = f1(y4, -4*(t2 + y4 + y6 + 2*y1)) + x5, x13 = f1(y5, -4*(t1 + y5 + y7 + 2*y2)) + x6, x14 = f1(y6, -4*(t2 + y6 + y8 + 2*y3)) + x15, x7 = f1(y7, -4*(t1 + y7 + y1 + 2*y4)) + x8, x16 = f1(y8, -4*(t2 + y8 + y2 + 2*y5)) + v1 = f2(x1, -4*(x1 + x2 + x3 + x6)) + v2 = f2(x2, -4*(x2 + x3 + x4 + x7)) + v3 = f2(x8, -4*(x8 + x9 + x10 + x13)) + v4 = f2(x9, -4*(x9 + x10 + x11 + x14)) + v5 = f2(x10, -4*(x10 + x11 + x12 + x15)) + v6 = f2(x16, -4*(x16 + x1 + x2 + x5)) + u1 = -f2(-v1, -4*(v2 + v3)) + u2 = -f2(-v4, -4*(v5 + v6)) + w1 = -2*f2(-u1, -4*u2) + return sqrt(sqrt(2)*sqrt(w1 + 4)/8 + S.Half) + + +def cos_table() -> dict[int, Callable[[], Expr]]: + r"""Lazily evaluated table for $\cos \frac{\pi}{n}$ in square roots for + $n \in \{3, 5, 17, 257, 65537\}$. + + Notes + ===== + + 65537 is the only other known Fermat prime and it is nearly impossible to + build in the current SymPy due to performance issues. + + References + ========== + + https://r-knott.surrey.ac.uk/Fibonacci/simpleTrig.html + """ + return { + 3: cos_3, + 5: cos_5, + 17: cos_17, + 257: cos_257 + } diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/benchmarks/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/benchmarks/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/benchmarks/bench_exp.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/benchmarks/bench_exp.py new file mode 100644 index 0000000000000000000000000000000000000000..fa18d29f87bcd249baec1d278a030fa7a133c3ba --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/benchmarks/bench_exp.py @@ -0,0 +1,11 @@ +from sympy.core.symbol import symbols +from sympy.functions.elementary.exponential import exp + +x, y = symbols('x,y') + +e = exp(2*x) +q = exp(3*x) + + +def timeit_exp_subs(): + e.subs(q, y) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/complexes.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/complexes.py new file mode 100644 index 0000000000000000000000000000000000000000..dd837e4e242057050370f38c4b4e9c26aa5d06c9 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/complexes.py @@ -0,0 +1,1492 @@ +from __future__ import annotations + +from sympy.core import S, Add, Mul, sympify, Symbol, Dummy, Basic +from sympy.core.expr import Expr +from sympy.core.exprtools import factor_terms +from sympy.core.function import (DefinedFunction, Derivative, ArgumentIndexError, + AppliedUndef, expand_mul, PoleError) +from sympy.core.logic import fuzzy_not, fuzzy_or +from sympy.core.numbers import pi, I, oo +from sympy.core.power import Pow +from sympy.core.relational import Eq +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise + +############################################################################### +######################### REAL and IMAGINARY PARTS ############################ +############################################################################### + + +class re(DefinedFunction): + """ + Returns real part of expression. This function performs only + elementary analysis and so it will fail to decompose properly + more complicated expressions. If completely simplified result + is needed then use ``Basic.as_real_imag()`` or perform complex + expansion on instance of this function. + + Examples + ======== + + >>> from sympy import re, im, I, E, symbols + >>> x, y = symbols('x y', real=True) + >>> re(2*E) + 2*E + >>> re(2*I + 17) + 17 + >>> re(2*I) + 0 + >>> re(im(x) + x*I + 2) + 2 + >>> re(5 + I + 2) + 7 + + Parameters + ========== + + arg : Expr + Real or complex expression. + + Returns + ======= + + expr : Expr + Real part of expression. + + See Also + ======== + + im + """ + + args: tuple[Expr] + + is_extended_real = True + unbranched = True # implicitly works on the projection to C + _singularities = True # non-holomorphic + + @classmethod + def eval(cls, arg): + if arg is S.NaN: + return S.NaN + elif arg is S.ComplexInfinity: + return S.NaN + elif arg.is_extended_real: + return arg + elif arg.is_imaginary or (I*arg).is_extended_real: + return S.Zero + elif arg.is_Matrix: + return arg.as_real_imag()[0] + elif arg.is_Function and isinstance(arg, conjugate): + return re(arg.args[0]) + else: + + included, reverted, excluded = [], [], [] + args = Add.make_args(arg) + for term in args: + coeff = term.as_coefficient(I) + + if coeff is not None: + if not coeff.is_extended_real: + reverted.append(coeff) + elif not term.has(I) and term.is_extended_real: + excluded.append(term) + else: + # Try to do some advanced expansion. If + # impossible, don't try to do re(arg) again + # (because this is what we are trying to do now). + real_imag = term.as_real_imag(ignore=arg) + if real_imag: + excluded.append(real_imag[0]) + else: + included.append(term) + + if len(args) != len(included): + a, b, c = (Add(*xs) for xs in [included, reverted, excluded]) + + return cls(a) - im(b) + c + + def as_real_imag(self, deep=True, **hints): + """ + Returns the real number with a zero imaginary part. + + """ + return (self, S.Zero) + + def _eval_derivative(self, x): + if x.is_extended_real or self.args[0].is_extended_real: + return re(Derivative(self.args[0], x, evaluate=True)) + if x.is_imaginary or self.args[0].is_imaginary: + return -I \ + * im(Derivative(self.args[0], x, evaluate=True)) + + def _eval_rewrite_as_im(self, arg, **kwargs): + return self.args[0] - I*im(self.args[0]) + + def _eval_is_algebraic(self): + return self.args[0].is_algebraic + + def _eval_is_zero(self): + # is_imaginary implies nonzero + return fuzzy_or([self.args[0].is_imaginary, self.args[0].is_zero]) + + def _eval_is_finite(self): + if self.args[0].is_finite: + return True + + def _eval_is_complex(self): + if self.args[0].is_finite: + return True + + +class im(DefinedFunction): + """ + Returns imaginary part of expression. This function performs only + elementary analysis and so it will fail to decompose properly more + complicated expressions. If completely simplified result is needed then + use ``Basic.as_real_imag()`` or perform complex expansion on instance of + this function. + + Examples + ======== + + >>> from sympy import re, im, E, I + >>> from sympy.abc import x, y + >>> im(2*E) + 0 + >>> im(2*I + 17) + 2 + >>> im(x*I) + re(x) + >>> im(re(x) + y) + im(y) + >>> im(2 + 3*I) + 3 + + Parameters + ========== + + arg : Expr + Real or complex expression. + + Returns + ======= + + expr : Expr + Imaginary part of expression. + + See Also + ======== + + re + """ + + args: tuple[Expr] + + is_extended_real = True + unbranched = True # implicitly works on the projection to C + _singularities = True # non-holomorphic + + @classmethod + def eval(cls, arg): + if arg is S.NaN: + return S.NaN + elif arg is S.ComplexInfinity: + return S.NaN + elif arg.is_extended_real: + return S.Zero + elif arg.is_imaginary or (I*arg).is_extended_real: + return -I * arg + elif arg.is_Matrix: + return arg.as_real_imag()[1] + elif arg.is_Function and isinstance(arg, conjugate): + return -im(arg.args[0]) + else: + included, reverted, excluded = [], [], [] + args = Add.make_args(arg) + for term in args: + coeff = term.as_coefficient(I) + + if coeff is not None: + if not coeff.is_extended_real: + reverted.append(coeff) + else: + excluded.append(coeff) + elif term.has(I) or not term.is_extended_real: + # Try to do some advanced expansion. If + # impossible, don't try to do im(arg) again + # (because this is what we are trying to do now). + real_imag = term.as_real_imag(ignore=arg) + if real_imag: + excluded.append(real_imag[1]) + else: + included.append(term) + + if len(args) != len(included): + a, b, c = (Add(*xs) for xs in [included, reverted, excluded]) + + return cls(a) + re(b) + c + + def as_real_imag(self, deep=True, **hints): + """ + Return the imaginary part with a zero real part. + + """ + return (self, S.Zero) + + def _eval_derivative(self, x): + if x.is_extended_real or self.args[0].is_extended_real: + return im(Derivative(self.args[0], x, evaluate=True)) + if x.is_imaginary or self.args[0].is_imaginary: + return -I \ + * re(Derivative(self.args[0], x, evaluate=True)) + + def _eval_rewrite_as_re(self, arg, **kwargs): + return -I*(self.args[0] - re(self.args[0])) + + def _eval_is_algebraic(self): + return self.args[0].is_algebraic + + def _eval_is_zero(self): + return self.args[0].is_extended_real + + def _eval_is_finite(self): + if self.args[0].is_finite: + return True + + def _eval_is_complex(self): + if self.args[0].is_finite: + return True + +############################################################################### +############### SIGN, ABSOLUTE VALUE, ARGUMENT and CONJUGATION ################ +############################################################################### + +class sign(DefinedFunction): + """ + Returns the complex sign of an expression: + + Explanation + =========== + + If the expression is real the sign will be: + + * $1$ if expression is positive + * $0$ if expression is equal to zero + * $-1$ if expression is negative + + If the expression is imaginary the sign will be: + + * $I$ if im(expression) is positive + * $-I$ if im(expression) is negative + + Otherwise an unevaluated expression will be returned. When evaluated, the + result (in general) will be ``cos(arg(expr)) + I*sin(arg(expr))``. + + Examples + ======== + + >>> from sympy import sign, I + + >>> sign(-1) + -1 + >>> sign(0) + 0 + >>> sign(-3*I) + -I + >>> sign(1 + I) + sign(1 + I) + >>> _.evalf() + 0.707106781186548 + 0.707106781186548*I + + Parameters + ========== + + arg : Expr + Real or imaginary expression. + + Returns + ======= + + expr : Expr + Complex sign of expression. + + See Also + ======== + + Abs, conjugate + """ + + is_complex = True + _singularities = True + + def doit(self, **hints): + s = super().doit() + if s == self and self.args[0].is_zero is False: + return self.args[0] / Abs(self.args[0]) + return s + + @classmethod + def eval(cls, arg): + # handle what we can + if arg.is_Mul: + c, args = arg.as_coeff_mul() + unk = [] + s = sign(c) + for a in args: + if a.is_extended_negative: + s = -s + elif a.is_extended_positive: + pass + else: + if a.is_imaginary: + ai = im(a) + if ai.is_comparable: # i.e. a = I*real + s *= I + if ai.is_extended_negative: + # can't use sign(ai) here since ai might not be + # a Number + s = -s + else: + unk.append(a) + else: + unk.append(a) + if c is S.One and len(unk) == len(args): + return None + return s * cls(arg._new_rawargs(*unk)) + if arg is S.NaN: + return S.NaN + if arg.is_zero: # it may be an Expr that is zero + return S.Zero + if arg.is_extended_positive: + return S.One + if arg.is_extended_negative: + return S.NegativeOne + if arg.is_Function: + if isinstance(arg, sign): + return arg + if arg.is_imaginary: + if arg.is_Pow and arg.exp is S.Half: + # we catch this because non-trivial sqrt args are not expanded + # e.g. sqrt(1-sqrt(2)) --x--> to I*sqrt(sqrt(2) - 1) + return I + arg2 = -I * arg + if arg2.is_extended_positive: + return I + if arg2.is_extended_negative: + return -I + + def _eval_Abs(self): + if fuzzy_not(self.args[0].is_zero): + return S.One + + def _eval_conjugate(self): + return sign(conjugate(self.args[0])) + + def _eval_derivative(self, x): + if self.args[0].is_extended_real: + from sympy.functions.special.delta_functions import DiracDelta + return 2 * Derivative(self.args[0], x, evaluate=True) \ + * DiracDelta(self.args[0]) + elif self.args[0].is_imaginary: + from sympy.functions.special.delta_functions import DiracDelta + return 2 * Derivative(self.args[0], x, evaluate=True) \ + * DiracDelta(-I * self.args[0]) + + def _eval_is_nonnegative(self): + if self.args[0].is_nonnegative: + return True + + def _eval_is_nonpositive(self): + if self.args[0].is_nonpositive: + return True + + def _eval_is_imaginary(self): + return self.args[0].is_imaginary + + def _eval_is_integer(self): + return self.args[0].is_extended_real + + def _eval_is_zero(self): + return self.args[0].is_zero + + def _eval_power(self, other): + if ( + fuzzy_not(self.args[0].is_zero) and + other.is_integer and + other.is_even + ): + return S.One + + def _eval_nseries(self, x, n, logx, cdir=0): + arg0 = self.args[0] + x0 = arg0.subs(x, 0) + if x0 != 0: + return self.func(x0) + if cdir != 0: + cdir = arg0.dir(x, cdir) + return -S.One if re(cdir) < 0 else S.One + + def _eval_rewrite_as_Piecewise(self, arg, **kwargs): + if arg.is_extended_real: + return Piecewise((1, arg > 0), (-1, arg < 0), (0, True)) + + def _eval_rewrite_as_Heaviside(self, arg, **kwargs): + from sympy.functions.special.delta_functions import Heaviside + if arg.is_extended_real: + return Heaviside(arg) * 2 - 1 + + def _eval_rewrite_as_Abs(self, arg, **kwargs): + return Piecewise((0, Eq(arg, 0)), (arg / Abs(arg), True)) + + def _eval_simplify(self, **kwargs): + return self.func(factor_terms(self.args[0])) # XXX include doit? + + +class Abs(DefinedFunction): + """ + Return the absolute value of the argument. + + Explanation + =========== + + This is an extension of the built-in function ``abs()`` to accept symbolic + values. If you pass a SymPy expression to the built-in ``abs()``, it will + pass it automatically to ``Abs()``. + + Examples + ======== + + >>> from sympy import Abs, Symbol, S, I + >>> Abs(-1) + 1 + >>> x = Symbol('x', real=True) + >>> Abs(-x) + Abs(x) + >>> Abs(x**2) + x**2 + >>> abs(-x) # The Python built-in + Abs(x) + >>> Abs(3*x + 2*I) + sqrt(9*x**2 + 4) + >>> Abs(8*I) + 8 + + Note that the Python built-in will return either an Expr or int depending on + the argument:: + + >>> type(abs(-1)) + <... 'int'> + >>> type(abs(S.NegativeOne)) + + + Abs will always return a SymPy object. + + Parameters + ========== + + arg : Expr + Real or complex expression. + + Returns + ======= + + expr : Expr + Absolute value returned can be an expression or integer depending on + input arg. + + See Also + ======== + + sign, conjugate + """ + + args: tuple[Expr] + + is_extended_real = True + is_extended_negative = False + is_extended_nonnegative = True + unbranched = True + _singularities = True # non-holomorphic + + def fdiff(self, argindex=1): + """ + Get the first derivative of the argument to Abs(). + + """ + if argindex == 1: + return sign(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + from sympy.simplify.simplify import signsimp + + if hasattr(arg, '_eval_Abs'): + obj = arg._eval_Abs() + if obj is not None: + return obj + if not isinstance(arg, Expr): + raise TypeError("Bad argument type for Abs(): %s" % type(arg)) + + # handle what we can + arg = signsimp(arg, evaluate=False) + n, d = arg.as_numer_denom() + if d.free_symbols and not n.free_symbols: + return cls(n)/cls(d) + + if arg.is_Mul: + known = [] + unk = [] + for t in arg.args: + if t.is_Pow and t.exp.is_integer and t.exp.is_negative: + bnew = cls(t.base) + if isinstance(bnew, cls): + unk.append(t) + else: + known.append(Pow(bnew, t.exp)) + else: + tnew = cls(t) + if isinstance(tnew, cls): + unk.append(t) + else: + known.append(tnew) + known = Mul(*known) + unk = cls(Mul(*unk), evaluate=False) if unk else S.One + return known*unk + if arg is S.NaN: + return S.NaN + if arg is S.ComplexInfinity: + return oo + from sympy.functions.elementary.exponential import exp, log + + if arg.is_Pow: + base, exponent = arg.as_base_exp() + if base.is_extended_real: + if exponent.is_integer: + if exponent.is_even: + return arg + if base is S.NegativeOne: + return S.One + return Abs(base)**exponent + if base.is_extended_nonnegative: + return base**re(exponent) + if base.is_extended_negative: + return (-base)**re(exponent)*exp(-pi*im(exponent)) + return + elif not base.has(Symbol): # complex base + # express base**exponent as exp(exponent*log(base)) + a, b = log(base).as_real_imag() + z = a + I*b + return exp(re(exponent*z)) + if isinstance(arg, exp): + return exp(re(arg.args[0])) + if isinstance(arg, AppliedUndef): + if arg.is_positive: + return arg + elif arg.is_negative: + return -arg + return + if arg.is_Add and arg.has(oo, S.NegativeInfinity): + if any(a.is_infinite for a in arg.as_real_imag()): + return oo + if arg.is_zero: + return S.Zero + if arg.is_extended_nonnegative: + return arg + if arg.is_extended_nonpositive: + return -arg + if arg.is_imaginary: + arg2 = -I * arg + if arg2.is_extended_nonnegative: + return arg2 + if arg.is_extended_real: + return + # reject result if all new conjugates are just wrappers around + # an expression that was already in the arg + conj = signsimp(arg.conjugate(), evaluate=False) + new_conj = conj.atoms(conjugate) - arg.atoms(conjugate) + if new_conj and all(arg.has(i.args[0]) for i in new_conj): + return + if arg != conj and arg != -conj: + ignore = arg.atoms(Abs) + abs_free_arg = arg.xreplace({i: Dummy(real=True) for i in ignore}) + unk = [a for a in abs_free_arg.free_symbols if a.is_extended_real is None] + if not unk or not all(conj.has(conjugate(u)) for u in unk): + return sqrt(expand_mul(arg*conj)) + + def _eval_is_real(self): + if self.args[0].is_finite: + return True + + def _eval_is_integer(self): + if self.args[0].is_extended_real: + return self.args[0].is_integer + + def _eval_is_extended_nonzero(self): + return fuzzy_not(self._args[0].is_zero) + + def _eval_is_zero(self): + return self._args[0].is_zero + + def _eval_is_extended_positive(self): + return fuzzy_not(self._args[0].is_zero) + + def _eval_is_rational(self): + if self.args[0].is_extended_real: + return self.args[0].is_rational + + def _eval_is_even(self): + if self.args[0].is_extended_real: + return self.args[0].is_even + + def _eval_is_odd(self): + if self.args[0].is_extended_real: + return self.args[0].is_odd + + def _eval_is_algebraic(self): + return self.args[0].is_algebraic + + def _eval_power(self, exponent): + if self.args[0].is_extended_real and exponent.is_integer: + if exponent.is_even: + return self.args[0]**exponent + elif exponent is not S.NegativeOne and exponent.is_Integer: + return self.args[0]**(exponent - 1)*self + return + + def _eval_nseries(self, x, n, logx, cdir=0): + from sympy.functions.elementary.exponential import log + direction = self.args[0].leadterm(x)[0] + if direction.has(log(x)): + direction = direction.subs(log(x), logx) + s = self.args[0]._eval_nseries(x, n=n, logx=logx) + return (sign(direction)*s).expand() + + def _eval_derivative(self, x): + if self.args[0].is_extended_real or self.args[0].is_imaginary: + return Derivative(self.args[0], x, evaluate=True) \ + * sign(conjugate(self.args[0])) + rv = (re(self.args[0]) * Derivative(re(self.args[0]), x, + evaluate=True) + im(self.args[0]) * Derivative(im(self.args[0]), + x, evaluate=True)) / Abs(self.args[0]) + return rv.rewrite(sign) + + def _eval_rewrite_as_Heaviside(self, arg, **kwargs): + # Note this only holds for real arg (since Heaviside is not defined + # for complex arguments). + from sympy.functions.special.delta_functions import Heaviside + if arg.is_extended_real: + return arg*(Heaviside(arg) - Heaviside(-arg)) + + def _eval_rewrite_as_Piecewise(self, arg, **kwargs): + if arg.is_extended_real: + return Piecewise((arg, arg >= 0), (-arg, True)) + elif arg.is_imaginary: + return Piecewise((I*arg, I*arg >= 0), (-I*arg, True)) + + def _eval_rewrite_as_sign(self, arg, **kwargs): + return arg/sign(arg) + + def _eval_rewrite_as_conjugate(self, arg, **kwargs): + return sqrt(arg*conjugate(arg)) + + +class arg(DefinedFunction): + r""" + Returns the argument (in radians) of a complex number. The argument is + evaluated in consistent convention with ``atan2`` where the branch-cut is + taken along the negative real axis and ``arg(z)`` is in the interval + $(-\pi,\pi]$. For a positive number, the argument is always 0; the + argument of a negative number is $\pi$; and the argument of 0 + is undefined and returns ``nan``. So the ``arg`` function will never nest + greater than 3 levels since at the 4th application, the result must be + nan; for a real number, nan is returned on the 3rd application. + + Examples + ======== + + >>> from sympy import arg, I, sqrt, Dummy + >>> from sympy.abc import x + >>> arg(2.0) + 0 + >>> arg(I) + pi/2 + >>> arg(sqrt(2) + I*sqrt(2)) + pi/4 + >>> arg(sqrt(3)/2 + I/2) + pi/6 + >>> arg(4 + 3*I) + atan(3/4) + >>> arg(0.8 + 0.6*I) + 0.643501108793284 + >>> arg(arg(arg(arg(x)))) + nan + >>> real = Dummy(real=True) + >>> arg(arg(arg(real))) + nan + + Parameters + ========== + + arg : Expr + Real or complex expression. + + Returns + ======= + + value : Expr + Returns arc tangent of arg measured in radians. + + """ + + is_extended_real = True + is_real = True + is_finite = True + _singularities = True # non-holomorphic + + @classmethod + def eval(cls, arg): + a = arg + for i in range(3): + if isinstance(a, cls): + a = a.args[0] + else: + if i == 2 and a.is_extended_real: + return S.NaN + break + else: + return S.NaN + from sympy.functions.elementary.exponential import exp, exp_polar + if isinstance(arg, exp_polar): + return periodic_argument(arg, oo) + elif isinstance(arg, exp): + i_ = im(arg.args[0]) + if i_.is_comparable: + i_ %= 2*S.Pi + if i_ > S.Pi: + i_ -= 2*S.Pi + return i_ + + if not arg.is_Atom: + c, arg_ = factor_terms(arg).as_coeff_Mul() + if arg_.is_Mul: + arg_ = Mul(*[a if (sign(a) not in (-1, 1)) else + sign(a) for a in arg_.args]) + arg_ = sign(c)*arg_ + else: + arg_ = arg + if any(i.is_extended_positive is None for i in arg_.atoms(AppliedUndef)): + return + from sympy.functions.elementary.trigonometric import atan2 + x, y = arg_.as_real_imag() + rv = atan2(y, x) + if rv.is_number: + return rv + if arg_ != arg: + return cls(arg_, evaluate=False) + + def _eval_derivative(self, t): + x, y = self.args[0].as_real_imag() + return (x * Derivative(y, t, evaluate=True) - y * + Derivative(x, t, evaluate=True)) / (x**2 + y**2) + + def _eval_rewrite_as_atan2(self, arg, **kwargs): + from sympy.functions.elementary.trigonometric import atan2 + x, y = self.args[0].as_real_imag() + return atan2(y, x) + + def _eval_as_leading_term(self, x, logx, cdir): + arg0 = self.args[0] + t = Dummy('t', positive=True) + if cdir == 0: + cdir = 1 + z = arg0.subs(x, cdir*t) + if z.is_positive: + return S.Zero + elif z.is_negative: + return S.Pi + else: + raise PoleError("Cannot expand %s around 0" % (self)) + + def _eval_nseries(self, x, n, logx, cdir=0): + from sympy.series.order import Order + if n <= 0: + return Order(1) + return self._eval_as_leading_term(x, logx=logx, cdir=cdir) + + +class conjugate(DefinedFunction): + """ + Returns the *complex conjugate* [1]_ of an argument. + In mathematics, the complex conjugate of a complex number + is given by changing the sign of the imaginary part. + + Thus, the conjugate of the complex number + :math:`a + ib` (where $a$ and $b$ are real numbers) is :math:`a - ib` + + Examples + ======== + + >>> from sympy import conjugate, I + >>> conjugate(2) + 2 + >>> conjugate(I) + -I + >>> conjugate(3 + 2*I) + 3 - 2*I + >>> conjugate(5 - I) + 5 + I + + Parameters + ========== + + arg : Expr + Real or complex expression. + + Returns + ======= + + arg : Expr + Complex conjugate of arg as real, imaginary or mixed expression. + + See Also + ======== + + sign, Abs + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Complex_conjugation + """ + _singularities = True # non-holomorphic + + @classmethod + def eval(cls, arg): + obj = arg._eval_conjugate() + if obj is not None: + return obj + + def inverse(self): + return conjugate + + def _eval_Abs(self): + return Abs(self.args[0], evaluate=True) + + def _eval_adjoint(self): + return transpose(self.args[0]) + + def _eval_conjugate(self): + return self.args[0] + + def _eval_derivative(self, x): + if x.is_real: + return conjugate(Derivative(self.args[0], x, evaluate=True)) + elif x.is_imaginary: + return -conjugate(Derivative(self.args[0], x, evaluate=True)) + + def _eval_transpose(self): + return adjoint(self.args[0]) + + def _eval_is_algebraic(self): + return self.args[0].is_algebraic + + +class transpose(DefinedFunction): + """ + Linear map transposition. + + Examples + ======== + + >>> from sympy import transpose, Matrix, MatrixSymbol + >>> A = MatrixSymbol('A', 25, 9) + >>> transpose(A) + A.T + >>> B = MatrixSymbol('B', 9, 22) + >>> transpose(B) + B.T + >>> transpose(A*B) + B.T*A.T + >>> M = Matrix([[4, 5], [2, 1], [90, 12]]) + >>> M + Matrix([ + [ 4, 5], + [ 2, 1], + [90, 12]]) + >>> transpose(M) + Matrix([ + [4, 2, 90], + [5, 1, 12]]) + + Parameters + ========== + + arg : Matrix + Matrix or matrix expression to take the transpose of. + + Returns + ======= + + value : Matrix + Transpose of arg. + + """ + + @classmethod + def eval(cls, arg): + obj = arg._eval_transpose() + if obj is not None: + return obj + + def _eval_adjoint(self): + return conjugate(self.args[0]) + + def _eval_conjugate(self): + return adjoint(self.args[0]) + + def _eval_transpose(self): + return self.args[0] + + +class adjoint(DefinedFunction): + """ + Conjugate transpose or Hermite conjugation. + + Examples + ======== + + >>> from sympy import adjoint, MatrixSymbol + >>> A = MatrixSymbol('A', 10, 5) + >>> adjoint(A) + Adjoint(A) + + Parameters + ========== + + arg : Matrix + Matrix or matrix expression to take the adjoint of. + + Returns + ======= + + value : Matrix + Represents the conjugate transpose or Hermite + conjugation of arg. + + """ + + @classmethod + def eval(cls, arg): + obj = arg._eval_adjoint() + if obj is not None: + return obj + obj = arg._eval_transpose() + if obj is not None: + return conjugate(obj) + + def _eval_adjoint(self): + return self.args[0] + + def _eval_conjugate(self): + return transpose(self.args[0]) + + def _eval_transpose(self): + return conjugate(self.args[0]) + + def _latex(self, printer, exp=None, *args): + arg = printer._print(self.args[0]) + tex = r'%s^{\dagger}' % arg + if exp: + tex = r'\left(%s\right)^{%s}' % (tex, exp) + return tex + + def _pretty(self, printer, *args): + from sympy.printing.pretty.stringpict import prettyForm + pform = printer._print(self.args[0], *args) + if printer._use_unicode: + pform = pform**prettyForm('\N{DAGGER}') + else: + pform = pform**prettyForm('+') + return pform + +############################################################################### +############### HANDLING OF POLAR NUMBERS ##################################### +############################################################################### + + +class polar_lift(DefinedFunction): + """ + Lift argument to the Riemann surface of the logarithm, using the + standard branch. + + Examples + ======== + + >>> from sympy import Symbol, polar_lift, I + >>> p = Symbol('p', polar=True) + >>> x = Symbol('x') + >>> polar_lift(4) + 4*exp_polar(0) + >>> polar_lift(-4) + 4*exp_polar(I*pi) + >>> polar_lift(-I) + exp_polar(-I*pi/2) + >>> polar_lift(I + 2) + polar_lift(2 + I) + + >>> polar_lift(4*x) + 4*polar_lift(x) + >>> polar_lift(4*p) + 4*p + + Parameters + ========== + + arg : Expr + Real or complex expression. + + See Also + ======== + + sympy.functions.elementary.exponential.exp_polar + periodic_argument + """ + + is_polar = True + is_comparable = False # Cannot be evalf'd. + + @classmethod + def eval(cls, arg): + from sympy.functions.elementary.complexes import arg as argument + if arg.is_number: + ar = argument(arg) + # In general we want to affirm that something is known, + # e.g. `not ar.has(argument) and not ar.has(atan)` + # but for now we will just be more restrictive and + # see that it has evaluated to one of the known values. + if ar in (0, pi/2, -pi/2, pi): + from sympy.functions.elementary.exponential import exp_polar + return exp_polar(I*ar)*abs(arg) + + if arg.is_Mul: + args = arg.args + else: + args = [arg] + included = [] + excluded = [] + positive = [] + for arg in args: + if arg.is_polar: + included += [arg] + elif arg.is_positive: + positive += [arg] + else: + excluded += [arg] + if len(excluded) < len(args): + if excluded: + return Mul(*(included + positive))*polar_lift(Mul(*excluded)) + elif included: + return Mul(*(included + positive)) + else: + from sympy.functions.elementary.exponential import exp_polar + return Mul(*positive)*exp_polar(0) + + def _eval_evalf(self, prec): + """ Careful! any evalf of polar numbers is flaky """ + return self.args[0]._eval_evalf(prec) + + def _eval_Abs(self): + return Abs(self.args[0], evaluate=True) + + +class periodic_argument(DefinedFunction): + r""" + Represent the argument on a quotient of the Riemann surface of the + logarithm. That is, given a period $P$, always return a value in + $(-P/2, P/2]$, by using $\exp(PI) = 1$. + + Examples + ======== + + >>> from sympy import exp_polar, periodic_argument + >>> from sympy import I, pi + >>> periodic_argument(exp_polar(10*I*pi), 2*pi) + 0 + >>> periodic_argument(exp_polar(5*I*pi), 4*pi) + pi + >>> from sympy import exp_polar, periodic_argument + >>> from sympy import I, pi + >>> periodic_argument(exp_polar(5*I*pi), 2*pi) + pi + >>> periodic_argument(exp_polar(5*I*pi), 3*pi) + -pi + >>> periodic_argument(exp_polar(5*I*pi), pi) + 0 + + Parameters + ========== + + ar : Expr + A polar number. + + period : Expr + The period $P$. + + See Also + ======== + + sympy.functions.elementary.exponential.exp_polar + polar_lift : Lift argument to the Riemann surface of the logarithm + principal_branch + """ + + @classmethod + def _getunbranched(cls, ar): + from sympy.functions.elementary.exponential import exp_polar, log + if ar.is_Mul: + args = ar.args + else: + args = [ar] + unbranched = 0 + for a in args: + if not a.is_polar: + unbranched += arg(a) + elif isinstance(a, exp_polar): + unbranched += a.exp.as_real_imag()[1] + elif a.is_Pow: + re, im = a.exp.as_real_imag() + unbranched += re*unbranched_argument( + a.base) + im*log(abs(a.base)) + elif isinstance(a, polar_lift): + unbranched += arg(a.args[0]) + else: + return None + return unbranched + + @classmethod + def eval(cls, ar, period): + # Our strategy is to evaluate the argument on the Riemann surface of the + # logarithm, and then reduce. + # NOTE evidently this means it is a rather bad idea to use this with + # period != 2*pi and non-polar numbers. + if not period.is_extended_positive: + return None + if period == oo and isinstance(ar, principal_branch): + return periodic_argument(*ar.args) + if isinstance(ar, polar_lift) and period >= 2*pi: + return periodic_argument(ar.args[0], period) + if ar.is_Mul: + newargs = [x for x in ar.args if not x.is_positive] + if len(newargs) != len(ar.args): + return periodic_argument(Mul(*newargs), period) + unbranched = cls._getunbranched(ar) + if unbranched is None: + return None + from sympy.functions.elementary.trigonometric import atan, atan2 + if unbranched.has(periodic_argument, atan2, atan): + return None + if period == oo: + return unbranched + if period != oo: + from sympy.functions.elementary.integers import ceiling + n = ceiling(unbranched/period - S.Half)*period + if not n.has(ceiling): + return unbranched - n + + def _eval_evalf(self, prec): + z, period = self.args + if period == oo: + unbranched = periodic_argument._getunbranched(z) + if unbranched is None: + return self + return unbranched._eval_evalf(prec) + ub = periodic_argument(z, oo)._eval_evalf(prec) + from sympy.functions.elementary.integers import ceiling + return (ub - ceiling(ub/period - S.Half)*period)._eval_evalf(prec) + + +def unbranched_argument(arg): + ''' + Returns periodic argument of arg with period as infinity. + + Examples + ======== + + >>> from sympy import exp_polar, unbranched_argument + >>> from sympy import I, pi + >>> unbranched_argument(exp_polar(15*I*pi)) + 15*pi + >>> unbranched_argument(exp_polar(7*I*pi)) + 7*pi + + See also + ======== + + periodic_argument + ''' + return periodic_argument(arg, oo) + + +class principal_branch(DefinedFunction): + """ + Represent a polar number reduced to its principal branch on a quotient + of the Riemann surface of the logarithm. + + Explanation + =========== + + This is a function of two arguments. The first argument is a polar + number `z`, and the second one a positive real number or infinity, `p`. + The result is ``z mod exp_polar(I*p)``. + + Examples + ======== + + >>> from sympy import exp_polar, principal_branch, oo, I, pi + >>> from sympy.abc import z + >>> principal_branch(z, oo) + z + >>> principal_branch(exp_polar(2*pi*I)*3, 2*pi) + 3*exp_polar(0) + >>> principal_branch(exp_polar(2*pi*I)*3*z, 2*pi) + 3*principal_branch(z, 2*pi) + + Parameters + ========== + + x : Expr + A polar number. + + period : Expr + Positive real number or infinity. + + See Also + ======== + + sympy.functions.elementary.exponential.exp_polar + polar_lift : Lift argument to the Riemann surface of the logarithm + periodic_argument + """ + + is_polar = True + is_comparable = False # cannot always be evalf'd + + @classmethod + def eval(self, x, period): + from sympy.functions.elementary.exponential import exp_polar + if isinstance(x, polar_lift): + return principal_branch(x.args[0], period) + if period == oo: + return x + ub = periodic_argument(x, oo) + barg = periodic_argument(x, period) + if ub != barg and not ub.has(periodic_argument) \ + and not barg.has(periodic_argument): + pl = polar_lift(x) + + def mr(expr): + if not isinstance(expr, Symbol): + return polar_lift(expr) + return expr + pl = pl.replace(polar_lift, mr) + # Recompute unbranched argument + ub = periodic_argument(pl, oo) + if not pl.has(polar_lift): + if ub != barg: + res = exp_polar(I*(barg - ub))*pl + else: + res = pl + if not res.is_polar and not res.has(exp_polar): + res *= exp_polar(0) + return res + + if not x.free_symbols: + c, m = x, () + else: + c, m = x.as_coeff_mul(*x.free_symbols) + others = [] + for y in m: + if y.is_positive: + c *= y + else: + others += [y] + m = tuple(others) + arg = periodic_argument(c, period) + if arg.has(periodic_argument): + return None + if arg.is_number and (unbranched_argument(c) != arg or + (arg == 0 and m != () and c != 1)): + if arg == 0: + return abs(c)*principal_branch(Mul(*m), period) + return principal_branch(exp_polar(I*arg)*Mul(*m), period)*abs(c) + if arg.is_number and ((abs(arg) < period/2) == True or arg == period/2) \ + and m == (): + return exp_polar(arg*I)*abs(c) + + def _eval_evalf(self, prec): + z, period = self.args + p = periodic_argument(z, period)._eval_evalf(prec) + if abs(p) > pi or p == -pi: + return self # Cannot evalf for this argument. + from sympy.functions.elementary.exponential import exp + return (abs(z)*exp(I*p))._eval_evalf(prec) + + +def _polarify(eq, lift, pause=False): + from sympy.integrals.integrals import Integral + if eq.is_polar: + return eq + if eq.is_number and not pause: + return polar_lift(eq) + if isinstance(eq, Symbol) and not pause and lift: + return polar_lift(eq) + elif eq.is_Atom: + return eq + elif eq.is_Add: + r = eq.func(*[_polarify(arg, lift, pause=True) for arg in eq.args]) + if lift: + return polar_lift(r) + return r + elif eq.is_Pow and eq.base == S.Exp1: + return eq.func(S.Exp1, _polarify(eq.exp, lift, pause=False)) + elif eq.is_Function: + return eq.func(*[_polarify(arg, lift, pause=False) for arg in eq.args]) + elif isinstance(eq, Integral): + # Don't lift the integration variable + func = _polarify(eq.function, lift, pause=pause) + limits = [] + for limit in eq.args[1:]: + var = _polarify(limit[0], lift=False, pause=pause) + rest = _polarify(limit[1:], lift=lift, pause=pause) + limits.append((var,) + rest) + return Integral(*((func,) + tuple(limits))) + else: + return eq.func(*[_polarify(arg, lift, pause=pause) + if isinstance(arg, Expr) else arg for arg in eq.args]) + + +def polarify(eq, subs=True, lift=False): + """ + Turn all numbers in eq into their polar equivalents (under the standard + choice of argument). + + Note that no attempt is made to guess a formal convention of adding + polar numbers, expressions like $1 + x$ will generally not be altered. + + Note also that this function does not promote ``exp(x)`` to ``exp_polar(x)``. + + If ``subs`` is ``True``, all symbols which are not already polar will be + substituted for polar dummies; in this case the function behaves much + like :func:`~.posify`. + + If ``lift`` is ``True``, both addition statements and non-polar symbols are + changed to their ``polar_lift()``ed versions. + Note that ``lift=True`` implies ``subs=False``. + + Examples + ======== + + >>> from sympy import polarify, sin, I + >>> from sympy.abc import x, y + >>> expr = (-x)**y + >>> expr.expand() + (-x)**y + >>> polarify(expr) + ((_x*exp_polar(I*pi))**_y, {_x: x, _y: y}) + >>> polarify(expr)[0].expand() + _x**_y*exp_polar(_y*I*pi) + >>> polarify(x, lift=True) + polar_lift(x) + >>> polarify(x*(1+y), lift=True) + polar_lift(x)*polar_lift(y + 1) + + Adds are treated carefully: + + >>> polarify(1 + sin((1 + I)*x)) + (sin(_x*polar_lift(1 + I)) + 1, {_x: x}) + """ + if lift: + subs = False + eq = _polarify(sympify(eq), lift) + if not subs: + return eq + reps = {s: Dummy(s.name, polar=True) for s in eq.free_symbols} + eq = eq.subs(reps) + return eq, {r: s for s, r in reps.items()} + + +def _unpolarify(eq, exponents_only, pause=False): + if not isinstance(eq, Basic) or eq.is_Atom: + return eq + + if not pause: + from sympy.functions.elementary.exponential import exp, exp_polar + if isinstance(eq, exp_polar): + return exp(_unpolarify(eq.exp, exponents_only)) + if isinstance(eq, principal_branch) and eq.args[1] == 2*pi: + return _unpolarify(eq.args[0], exponents_only) + if ( + eq.is_Add or eq.is_Mul or eq.is_Boolean or + eq.is_Relational and ( + eq.rel_op in ('==', '!=') and 0 in eq.args or + eq.rel_op not in ('==', '!=')) + ): + return eq.func(*[_unpolarify(x, exponents_only) for x in eq.args]) + if isinstance(eq, polar_lift): + return _unpolarify(eq.args[0], exponents_only) + + if eq.is_Pow: + expo = _unpolarify(eq.exp, exponents_only) + base = _unpolarify(eq.base, exponents_only, + not (expo.is_integer and not pause)) + return base**expo + + if eq.is_Function and getattr(eq.func, 'unbranched', False): + return eq.func(*[_unpolarify(x, exponents_only, exponents_only) + for x in eq.args]) + + return eq.func(*[_unpolarify(x, exponents_only, True) for x in eq.args]) + + +def unpolarify(eq, subs=None, exponents_only=False): + """ + If `p` denotes the projection from the Riemann surface of the logarithm to + the complex line, return a simplified version `eq'` of `eq` such that + `p(eq') = p(eq)`. + Also apply the substitution subs in the end. (This is a convenience, since + ``unpolarify``, in a certain sense, undoes :func:`polarify`.) + + Examples + ======== + + >>> from sympy import unpolarify, polar_lift, sin, I + >>> unpolarify(polar_lift(I + 2)) + 2 + I + >>> unpolarify(sin(polar_lift(I + 7))) + sin(7 + I) + """ + if isinstance(eq, bool): + return eq + + eq = sympify(eq) + if subs is not None: + return unpolarify(eq.subs(subs)) + changed = True + pause = False + if exponents_only: + pause = True + while changed: + changed = False + res = _unpolarify(eq, exponents_only, pause) + if res != eq: + changed = True + eq = res + if isinstance(res, bool): + return res + # Finally, replacing Exp(0) by 1 is always correct. + # So is polar_lift(0) -> 0. + from sympy.functions.elementary.exponential import exp_polar + return res.subs({exp_polar(0): 1, polar_lift(0): 0}) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/exponential.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/exponential.py new file mode 100644 index 0000000000000000000000000000000000000000..2bb0333cb34a35a96248c12a4640e848986f2feb --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/exponential.py @@ -0,0 +1,1286 @@ +from __future__ import annotations +from itertools import product + +from sympy.core.add import Add +from sympy.core.cache import cacheit +from sympy.core.expr import Expr +from sympy.core.function import (DefinedFunction, ArgumentIndexError, expand_log, + expand_mul, FunctionClass, PoleError, expand_multinomial, expand_complex) +from sympy.core.logic import fuzzy_and, fuzzy_not, fuzzy_or +from sympy.core.mul import Mul +from sympy.core.numbers import Integer, Rational, pi, I +from sympy.core.parameters import global_parameters +from sympy.core.power import Pow +from sympy.core.singleton import S +from sympy.core.symbol import Wild, Dummy +from sympy.core.sympify import sympify +from sympy.functions.combinatorial.factorials import factorial +from sympy.functions.elementary.complexes import arg, unpolarify, im, re, Abs +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.ntheory import multiplicity, perfect_power +from sympy.ntheory.factor_ import factorint + +# NOTE IMPORTANT +# The series expansion code in this file is an important part of the gruntz +# algorithm for determining limits. _eval_nseries has to return a generalized +# power series with coefficients in C(log(x), log). +# In more detail, the result of _eval_nseries(self, x, n) must be +# c_0*x**e_0 + ... (finitely many terms) +# where e_i are numbers (not necessarily integers) and c_i involve only +# numbers, the function log, and log(x). [This also means it must not contain +# log(x(1+p)), this *has* to be expanded to log(x)+log(1+p) if x.is_positive and +# p.is_positive.] + + +class ExpBase(DefinedFunction): + + unbranched = True + _singularities = (S.ComplexInfinity,) + + @property + def kind(self): + return self.exp.kind + + def inverse(self, argindex=1): + """ + Returns the inverse function of ``exp(x)``. + """ + return log + + def as_numer_denom(self): + """ + Returns this with a positive exponent as a 2-tuple (a fraction). + + Examples + ======== + + >>> from sympy import exp + >>> from sympy.abc import x + >>> exp(-x).as_numer_denom() + (1, exp(x)) + >>> exp(x).as_numer_denom() + (exp(x), 1) + """ + # this should be the same as Pow.as_numer_denom wrt + # exponent handling + if not self.is_commutative: + return self, S.One + exp = self.exp + neg_exp = exp.is_negative + if not neg_exp and not (-exp).is_negative: + neg_exp = exp.could_extract_minus_sign() + if neg_exp: + return S.One, self.func(-exp) + return self, S.One + + @property + def exp(self): + """ + Returns the exponent of the function. + """ + return self.args[0] + + def as_base_exp(self): + """ + Returns the 2-tuple (base, exponent). + """ + return self.func(1), Mul(*self.args) + + def _eval_adjoint(self): + return self.func(self.exp.adjoint()) + + def _eval_conjugate(self): + return self.func(self.exp.conjugate()) + + def _eval_transpose(self): + return self.func(self.exp.transpose()) + + def _eval_is_finite(self): + arg = self.exp + if arg.is_infinite: + if arg.is_extended_negative: + return True + if arg.is_extended_positive: + return False + if arg.is_finite: + return True + + def _eval_is_rational(self): + s = self.func(*self.args) + if s.func == self.func: + z = s.exp.is_zero + if z: + return True + elif s.exp.is_rational and fuzzy_not(z): + return False + else: + return s.is_rational + + def _eval_is_zero(self): + return self.exp is S.NegativeInfinity + + def _eval_power(self, other): + """exp(arg)**e -> exp(arg*e) if assumptions allow it. + """ + b, e = self.as_base_exp() + return Pow._eval_power(Pow(b, e, evaluate=False), other) + + def _eval_expand_power_exp(self, **hints): + from sympy.concrete.products import Product + from sympy.concrete.summations import Sum + arg = self.args[0] + if arg.is_Add and arg.is_commutative: + return Mul.fromiter(self.func(x) for x in arg.args) + elif isinstance(arg, Sum) and arg.is_commutative: + return Product(self.func(arg.function), *arg.limits) + return self.func(arg) + + +class exp_polar(ExpBase): + r""" + Represent a *polar number* (see g-function Sphinx documentation). + + Explanation + =========== + + ``exp_polar`` represents the function + `Exp: \mathbb{C} \rightarrow \mathcal{S}`, sending the complex number + `z = a + bi` to the polar number `r = exp(a), \theta = b`. It is one of + the main functions to construct polar numbers. + + Examples + ======== + + >>> from sympy import exp_polar, pi, I, exp + + The main difference is that polar numbers do not "wrap around" at `2 \pi`: + + >>> exp(2*pi*I) + 1 + >>> exp_polar(2*pi*I) + exp_polar(2*I*pi) + + apart from that they behave mostly like classical complex numbers: + + >>> exp_polar(2)*exp_polar(3) + exp_polar(5) + + See Also + ======== + + sympy.simplify.powsimp.powsimp + polar_lift + periodic_argument + principal_branch + """ + + is_polar = True + is_comparable = False # cannot be evalf'd + + def _eval_Abs(self): # Abs is never a polar number + return exp(re(self.args[0])) + + def _eval_evalf(self, prec): + """ Careful! any evalf of polar numbers is flaky """ + i = im(self.args[0]) + try: + bad = (i <= -pi or i > pi) + except TypeError: + bad = True + if bad: + return self # cannot evalf for this argument + res = exp(self.args[0])._eval_evalf(prec) + if i > 0 and im(res) < 0: + # i ~ pi, but exp(I*i) evaluated to argument slightly bigger than pi + return re(res) + return res + + def _eval_power(self, other): + return self.func(self.args[0]*other) + + def _eval_is_extended_real(self): + if self.args[0].is_extended_real: + return True + + def as_base_exp(self): + # XXX exp_polar(0) is special! + if self.args[0] == 0: + return self, S.One + return ExpBase.as_base_exp(self) + + +class ExpMeta(FunctionClass): + def __instancecheck__(cls, instance): + if exp in instance.__class__.__mro__: + return True + return isinstance(instance, Pow) and instance.base is S.Exp1 + + +class exp(ExpBase, metaclass=ExpMeta): + """ + The exponential function, :math:`e^x`. + + Examples + ======== + + >>> from sympy import exp, I, pi + >>> from sympy.abc import x + >>> exp(x) + exp(x) + >>> exp(x).diff(x) + exp(x) + >>> exp(I*pi) + -1 + + Parameters + ========== + + arg : Expr + + See Also + ======== + + log + """ + + def fdiff(self, argindex=1): + """ + Returns the first derivative of this function. + """ + if argindex == 1: + return self + else: + raise ArgumentIndexError(self, argindex) + + def _eval_refine(self, assumptions): + from sympy.assumptions import ask, Q + arg = self.args[0] + if arg.is_Mul: + Ioo = I*S.Infinity + if arg in [Ioo, -Ioo]: + return S.NaN + + coeff = arg.as_coefficient(pi*I) + if coeff: + if ask(Q.integer(2*coeff)): + if ask(Q.even(coeff)): + return S.One + elif ask(Q.odd(coeff)): + return S.NegativeOne + elif ask(Q.even(coeff + S.Half)): + return -I + elif ask(Q.odd(coeff + S.Half)): + return I + + @classmethod + def eval(cls, arg): + from sympy.calculus import AccumBounds + from sympy.matrices.matrixbase import MatrixBase + from sympy.sets.setexpr import SetExpr + from sympy.simplify.simplify import logcombine + if isinstance(arg, MatrixBase): + return arg.exp() + elif global_parameters.exp_is_pow: + return Pow(S.Exp1, arg) + elif arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg.is_zero: + return S.One + elif arg is S.One: + return S.Exp1 + elif arg is S.Infinity: + return S.Infinity + elif arg is S.NegativeInfinity: + return S.Zero + elif arg is S.ComplexInfinity: + return S.NaN + elif isinstance(arg, log): + return arg.args[0] + elif isinstance(arg, AccumBounds): + return AccumBounds(exp(arg.min), exp(arg.max)) + elif isinstance(arg, SetExpr): + return arg._eval_func(cls) + elif arg.is_Mul: + coeff = arg.as_coefficient(pi*I) + if coeff: + if (2*coeff).is_integer: + if coeff.is_even: + return S.One + elif coeff.is_odd: + return S.NegativeOne + elif (coeff + S.Half).is_even: + return -I + elif (coeff + S.Half).is_odd: + return I + elif coeff.is_Rational: + ncoeff = coeff % 2 # restrict to [0, 2pi) + if ncoeff > 1: # restrict to (-pi, pi] + ncoeff -= 2 + if ncoeff != coeff: + return cls(ncoeff*pi*I) + + # Warning: code in risch.py will be very sensitive to changes + # in this (see DifferentialExtension). + + # look for a single log factor + + coeff, terms = arg.as_coeff_Mul() + + # but it can't be multiplied by oo + if coeff in [S.NegativeInfinity, S.Infinity]: + if terms.is_number: + if coeff is S.NegativeInfinity: + terms = -terms + if re(terms).is_zero and terms is not S.Zero: + return S.NaN + if re(terms).is_positive and im(terms) is not S.Zero: + return S.ComplexInfinity + if re(terms).is_negative: + return S.Zero + return None + + coeffs, log_term = [coeff], None + for term in Mul.make_args(terms): + term_ = logcombine(term) + if isinstance(term_, log): + if log_term is None: + log_term = term_.args[0] + else: + return None + elif term.is_comparable: + coeffs.append(term) + else: + return None + + return log_term**Mul(*coeffs) if log_term else None + + elif arg.is_Add: + out = [] + add = [] + argchanged = False + for a in arg.args: + if a is S.One: + add.append(a) + continue + newa = cls(a) + if isinstance(newa, cls): + if newa.args[0] != a: + add.append(newa.args[0]) + argchanged = True + else: + add.append(a) + else: + out.append(newa) + if out or argchanged: + return Mul(*out)*cls(Add(*add), evaluate=False) + + if arg.is_zero: + return S.One + + @property + def base(self): + """ + Returns the base of the exponential function. + """ + return S.Exp1 + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + """ + Calculates the next term in the Taylor series expansion. + """ + if n < 0: + return S.Zero + if n == 0: + return S.One + x = sympify(x) + if previous_terms: + p = previous_terms[-1] + if p is not None: + return p * x / n + return x**n/factorial(n) + + def as_real_imag(self, deep=True, **hints): + """ + Returns this function as a 2-tuple representing a complex number. + + Examples + ======== + + >>> from sympy import exp, I + >>> from sympy.abc import x + >>> exp(x).as_real_imag() + (exp(re(x))*cos(im(x)), exp(re(x))*sin(im(x))) + >>> exp(1).as_real_imag() + (E, 0) + >>> exp(I).as_real_imag() + (cos(1), sin(1)) + >>> exp(1+I).as_real_imag() + (E*cos(1), E*sin(1)) + + See Also + ======== + + sympy.functions.elementary.complexes.re + sympy.functions.elementary.complexes.im + """ + from sympy.functions.elementary.trigonometric import cos, sin + re, im = self.args[0].as_real_imag() + if deep: + re = re.expand(deep, **hints) + im = im.expand(deep, **hints) + cos, sin = cos(im), sin(im) + return (exp(re)*cos, exp(re)*sin) + + def _eval_subs(self, old, new): + # keep processing of power-like args centralized in Pow + if old.is_Pow: # handle (exp(3*log(x))).subs(x**2, z) -> z**(3/2) + old = exp(old.exp*log(old.base)) + elif old is S.Exp1 and new.is_Function: + old = exp + if isinstance(old, exp) or old is S.Exp1: + f = lambda a: Pow(*a.as_base_exp(), evaluate=False) if ( + a.is_Pow or isinstance(a, exp)) else a + return Pow._eval_subs(f(self), f(old), new) + + if old is exp and not new.is_Function: + return new**self.exp._subs(old, new) + return super()._eval_subs(old, new) + + def _eval_is_extended_real(self): + if self.args[0].is_extended_real: + return True + elif self.args[0].is_imaginary: + arg2 = -S(2) * I * self.args[0] / pi + return arg2.is_even + + def _eval_is_complex(self): + def complex_extended_negative(arg): + yield arg.is_complex + yield arg.is_extended_negative + return fuzzy_or(complex_extended_negative(self.args[0])) + + def _eval_is_algebraic(self): + if (self.exp / pi / I).is_rational: + return True + if fuzzy_not(self.exp.is_zero): + if self.exp.is_algebraic: + return False + elif (self.exp / pi).is_rational: + return False + + def _eval_is_extended_positive(self): + if self.exp.is_extended_real: + return self.args[0] is not S.NegativeInfinity + elif self.exp.is_imaginary: + arg2 = -I * self.args[0] / pi + return arg2.is_even + + def _eval_nseries(self, x, n, logx, cdir=0): + # NOTE Please see the comment at the beginning of this file, labelled + # IMPORTANT. + from sympy.functions.elementary.complexes import sign + from sympy.functions.elementary.integers import ceiling + from sympy.series.limits import limit + from sympy.series.order import Order + from sympy.simplify.powsimp import powsimp + arg = self.exp + arg_series = arg._eval_nseries(x, n=n, logx=logx) + if arg_series.is_Order: + return 1 + arg_series + arg0 = limit(arg_series.removeO(), x, 0) + if arg0 is S.NegativeInfinity: + return Order(x**n, x) + if arg0 is S.Infinity: + return self + if arg0.is_infinite: + raise PoleError("Cannot expand %s around 0" % (self)) + # checking for indecisiveness/ sign terms in arg0 + if any(isinstance(arg, sign) for arg in arg0.args): + return self + t = Dummy("t") + nterms = n + try: + cf = Order(arg.as_leading_term(x, logx=logx), x).getn() + except (NotImplementedError, PoleError): + cf = 0 + if cf and cf > 0: + nterms = ceiling(n/cf) + exp_series = exp(t)._taylor(t, nterms) + r = exp(arg0)*exp_series.subs(t, arg_series - arg0) + rep = {logx: log(x)} if logx is not None else {} + if r.subs(rep) == self: + return r + if cf and cf > 1: + r += Order((arg_series - arg0)**n, x)/x**((cf-1)*n) + else: + r += Order((arg_series - arg0)**n, x) + r = r.expand() + r = powsimp(r, deep=True, combine='exp') + # powsimp may introduce unexpanded (-1)**Rational; see PR #17201 + simplerat = lambda x: x.is_Rational and x.q in [3, 4, 6] + w = Wild('w', properties=[simplerat]) + r = r.replace(S.NegativeOne**w, expand_complex(S.NegativeOne**w)) + return r + + def _taylor(self, x, n): + l = [] + g = None + for i in range(n): + g = self.taylor_term(i, self.args[0], g) + g = g.nseries(x, n=n) + l.append(g.removeO()) + return Add(*l) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.util import AccumBounds + arg = self.args[0].cancel().as_leading_term(x, logx=logx) + arg0 = arg.subs(x, 0) + if arg is S.NaN: + return S.NaN + if isinstance(arg0, AccumBounds): + # This check addresses a corner case involving AccumBounds. + # if isinstance(arg, AccumBounds) is True, then arg0 can either be 0, + # AccumBounds(-oo, 0) or AccumBounds(-oo, oo). + # Check out function: test_issue_18473() in test_exponential.py and + # test_limits.py for more information. + if re(cdir) < S.Zero: + return exp(-arg0) + return exp(arg0) + if arg0 is S.NaN: + arg0 = arg.limit(x, 0) + if arg0.is_infinite is False: + return exp(arg0) + raise PoleError("Cannot expand %s around 0" % (self)) + + def _eval_rewrite_as_sin(self, arg, **kwargs): + from sympy.functions.elementary.trigonometric import sin + return sin(I*arg + pi/2) - I*sin(I*arg) + + def _eval_rewrite_as_cos(self, arg, **kwargs): + from sympy.functions.elementary.trigonometric import cos + return cos(I*arg) + I*cos(I*arg + pi/2) + + def _eval_rewrite_as_tanh(self, arg, **kwargs): + from sympy.functions.elementary.hyperbolic import tanh + return (1 + tanh(arg/2))/(1 - tanh(arg/2)) + + def _eval_rewrite_as_sqrt(self, arg, **kwargs): + from sympy.functions.elementary.trigonometric import sin, cos + if arg.is_Mul: + coeff = arg.coeff(pi*I) + if coeff and coeff.is_number: + cosine, sine = cos(pi*coeff), sin(pi*coeff) + if not isinstance(cosine, cos) and not isinstance (sine, sin): + return cosine + I*sine + + def _eval_rewrite_as_Pow(self, arg, **kwargs): + if arg.is_Mul: + logs = [a for a in arg.args if isinstance(a, log) and len(a.args) == 1] + if logs: + return Pow(logs[0].args[0], arg.coeff(logs[0])) + + +def match_real_imag(expr): + r""" + Try to match expr with $a + Ib$ for real $a$ and $b$. + + ``match_real_imag`` returns a tuple containing the real and imaginary + parts of expr or ``(None, None)`` if direct matching is not possible. Contrary + to :func:`~.re`, :func:`~.im``, and ``as_real_imag()``, this helper will not force things + by returning expressions themselves containing ``re()`` or ``im()`` and it + does not expand its argument either. + + """ + r_, i_ = expr.as_independent(I, as_Add=True) + if i_ == 0 and r_.is_real: + return (r_, i_) + i_ = i_.as_coefficient(I) + if i_ and i_.is_real and r_.is_real: + return (r_, i_) + else: + return (None, None) # simpler to check for than None + + +class log(DefinedFunction): + r""" + The natural logarithm function `\ln(x)` or `\log(x)`. + + Explanation + =========== + + Logarithms are taken with the natural base, `e`. To get + a logarithm of a different base ``b``, use ``log(x, b)``, + which is essentially short-hand for ``log(x)/log(b)``. + + ``log`` represents the principal branch of the natural + logarithm. As such it has a branch cut along the negative + real axis and returns values having a complex argument in + `(-\pi, \pi]`. + + Examples + ======== + + >>> from sympy import log, sqrt, S, I + >>> log(8, 2) + 3 + >>> log(S(8)/3, 2) + -log(3)/log(2) + 3 + >>> log(-1 + I*sqrt(3)) + log(2) + 2*I*pi/3 + + See Also + ======== + + exp + + """ + + args: tuple[Expr] + + _singularities = (S.Zero, S.ComplexInfinity) + + def fdiff(self, argindex=1): + """ + Returns the first derivative of the function. + """ + if argindex == 1: + return 1/self.args[0] + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + r""" + Returns `e^x`, the inverse function of `\log(x)`. + """ + return exp + + @classmethod + def eval(cls, arg, base=None): + from sympy.calculus import AccumBounds + from sympy.sets.setexpr import SetExpr + + arg = sympify(arg) + + if base is not None: + base = sympify(base) + if base == 1: + if arg == 1: + return S.NaN + else: + return S.ComplexInfinity + try: + # handle extraction of powers of the base now + # or else expand_log in Mul would have to handle this + n = multiplicity(base, arg) + if n: + return n + log(arg / base**n) / log(base) + else: + return log(arg)/log(base) + except ValueError: + pass + if base is not S.Exp1: + return cls(arg)/cls(base) + else: + return cls(arg) + + if arg.is_Number: + if arg.is_zero: + return S.ComplexInfinity + elif arg is S.One: + return S.Zero + elif arg is S.Infinity: + return S.Infinity + elif arg is S.NegativeInfinity: + return S.Infinity + elif arg is S.NaN: + return S.NaN + elif arg.is_Rational and arg.p == 1: + return -cls(arg.q) + + if arg.is_Pow and arg.base is S.Exp1 and arg.exp.is_extended_real: + return arg.exp + if isinstance(arg, exp) and arg.exp.is_extended_real: + return arg.exp + elif isinstance(arg, exp) and arg.exp.is_number: + r_, i_ = match_real_imag(arg.exp) + if i_ and i_.is_comparable: + i_ %= 2*pi + if i_ > pi: + i_ -= 2*pi + return r_ + expand_mul(i_ * I, deep=False) + elif isinstance(arg, exp_polar): + return unpolarify(arg.exp) + elif isinstance(arg, AccumBounds): + if arg.min.is_positive: + return AccumBounds(log(arg.min), log(arg.max)) + elif arg.min.is_zero: + return AccumBounds(S.NegativeInfinity, log(arg.max)) + else: + return S.NaN + elif isinstance(arg, SetExpr): + return arg._eval_func(cls) + + if arg.is_number: + if arg.is_negative: + return pi * I + cls(-arg) + elif arg is S.ComplexInfinity: + return S.ComplexInfinity + elif arg is S.Exp1: + return S.One + + if arg.is_zero: + return S.ComplexInfinity + + # don't autoexpand Pow or Mul (see the issue 3351): + if not arg.is_Add: + coeff = arg.as_coefficient(I) + + if coeff is not None: + if coeff is S.Infinity: + return S.Infinity + elif coeff is S.NegativeInfinity: + return S.Infinity + elif coeff.is_Rational: + if coeff.is_nonnegative: + return pi * I * S.Half + cls(coeff) + else: + return -pi * I * S.Half + cls(-coeff) + + if arg.is_number and arg.is_algebraic: + # Match arg = coeff*(r_ + i_*I) with coeff>0, r_ and i_ real. + coeff, arg_ = arg.as_independent(I, as_Add=False) + if coeff.is_negative: + coeff *= -1 + arg_ *= -1 + arg_ = expand_mul(arg_, deep=False) + r_, i_ = arg_.as_independent(I, as_Add=True) + i_ = i_.as_coefficient(I) + if coeff.is_real and i_ and i_.is_real and r_.is_real: + if r_.is_zero: + if i_.is_positive: + return pi * I * S.Half + cls(coeff * i_) + elif i_.is_negative: + return -pi * I * S.Half + cls(coeff * -i_) + else: + from sympy.simplify import ratsimp + # Check for arguments involving rational multiples of pi + t = (i_/r_).cancel() + t1 = (-t).cancel() + atan_table = _log_atan_table() + if t in atan_table: + modulus = ratsimp(coeff * Abs(arg_)) + if r_.is_positive: + return cls(modulus) + I * atan_table[t] + else: + return cls(modulus) + I * (atan_table[t] - pi) + elif t1 in atan_table: + modulus = ratsimp(coeff * Abs(arg_)) + if r_.is_positive: + return cls(modulus) + I * (-atan_table[t1]) + else: + return cls(modulus) + I * (pi - atan_table[t1]) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): # of log(1+x) + r""" + Returns the next term in the Taylor series expansion of `\log(1+x)`. + """ + from sympy.simplify.powsimp import powsimp + if n < 0: + return S.Zero + x = sympify(x) + if n == 0: + return x + if previous_terms: + p = previous_terms[-1] + if p is not None: + return powsimp((-n) * p * x / (n + 1), deep=True, combine='exp') + return (1 - 2*(n % 2)) * x**(n + 1)/(n + 1) + + def _eval_expand_log(self, deep=True, **hints): + from sympy.concrete import Sum, Product + force = hints.get('force', False) + factor = hints.get('factor', False) + if (len(self.args) == 2): + return expand_log(self.func(*self.args), deep=deep, force=force) + arg = self.args[0] + if arg.is_Integer: + # remove perfect powers + p = perfect_power(arg) + logarg = None + coeff = 1 + if p is not False: + arg, coeff = p + logarg = self.func(arg) + # expand as product of its prime factors if factor=True + if factor: + p = factorint(arg) + if arg not in p.keys(): + logarg = sum(n*log(val) for val, n in p.items()) + if logarg is not None: + return coeff*logarg + elif arg.is_Rational: + return log(arg.p) - log(arg.q) + elif arg.is_Mul: + expr = [] + nonpos = [] + for x in arg.args: + if force or x.is_positive or x.is_polar: + a = self.func(x) + if isinstance(a, log): + expr.append(self.func(x)._eval_expand_log(**hints)) + else: + expr.append(a) + elif x.is_negative: + a = self.func(-x) + expr.append(a) + nonpos.append(S.NegativeOne) + else: + nonpos.append(x) + return Add(*expr) + log(Mul(*nonpos)) + elif arg.is_Pow or isinstance(arg, exp): + if force or (arg.exp.is_extended_real and (arg.base.is_positive or ((arg.exp+1) + .is_positive and (arg.exp-1).is_nonpositive))) or arg.base.is_polar: + b = arg.base + e = arg.exp + a = self.func(b) + if isinstance(a, log): + return unpolarify(e) * a._eval_expand_log(**hints) + else: + return unpolarify(e) * a + elif isinstance(arg, Product): + if force or arg.function.is_positive: + return Sum(log(arg.function), *arg.limits) + + return self.func(arg) + + def _eval_simplify(self, **kwargs): + from sympy.simplify.simplify import expand_log, simplify, inversecombine + if len(self.args) == 2: # it's unevaluated + return simplify(self.func(*self.args), **kwargs) + + expr = self.func(simplify(self.args[0], **kwargs)) + if kwargs['inverse']: + expr = inversecombine(expr) + expr = expand_log(expr, deep=True) + return min([expr, self], key=kwargs['measure']) + + def as_real_imag(self, deep=True, **hints): + """ + Returns this function as a complex coordinate. + + Examples + ======== + + >>> from sympy import I, log + >>> from sympy.abc import x + >>> log(x).as_real_imag() + (log(Abs(x)), arg(x)) + >>> log(I).as_real_imag() + (0, pi/2) + >>> log(1 + I).as_real_imag() + (log(sqrt(2)), pi/4) + >>> log(I*x).as_real_imag() + (log(Abs(x)), arg(I*x)) + + """ + sarg = self.args[0] + if deep: + sarg = self.args[0].expand(deep, **hints) + sarg_abs = Abs(sarg) + if sarg_abs == sarg: + return self, S.Zero + sarg_arg = arg(sarg) + if hints.get('log', False): # Expand the log + hints['complex'] = False + return (log(sarg_abs).expand(deep, **hints), sarg_arg) + else: + return log(sarg_abs), sarg_arg + + def _eval_is_rational(self): + s = self.func(*self.args) + if s.func == self.func: + if (self.args[0] - 1).is_zero: + return True + if s.args[0].is_rational and fuzzy_not((self.args[0] - 1).is_zero): + return False + else: + return s.is_rational + + def _eval_is_algebraic(self): + s = self.func(*self.args) + if s.func == self.func: + if (self.args[0] - 1).is_zero: + return True + elif fuzzy_not((self.args[0] - 1).is_zero): + if self.args[0].is_algebraic: + return False + else: + return s.is_algebraic + + def _eval_is_extended_real(self): + return self.args[0].is_extended_positive + + def _eval_is_complex(self): + z = self.args[0] + return fuzzy_and([z.is_complex, fuzzy_not(z.is_zero)]) + + def _eval_is_finite(self): + arg = self.args[0] + if arg.is_zero: + return False + return arg.is_finite + + def _eval_is_extended_positive(self): + return (self.args[0] - 1).is_extended_positive + + def _eval_is_zero(self): + return (self.args[0] - 1).is_zero + + def _eval_is_extended_nonnegative(self): + return (self.args[0] - 1).is_extended_nonnegative + + def _eval_nseries(self, x, n, logx, cdir=0): + # NOTE Please see the comment at the beginning of this file, labelled + # IMPORTANT. + from sympy.series.order import Order + from sympy.simplify.simplify import logcombine + from sympy.core.symbol import Dummy + + if self.args[0] == x: + return log(x) if logx is None else logx + arg = self.args[0] + t = Dummy('t', positive=True) + if cdir == 0: + cdir = 1 + z = arg.subs(x, cdir*t) + + k, l = Wild("k"), Wild("l") + r = z.match(k*t**l) + if r is not None: + k, l = r[k], r[l] + if l != 0 and not l.has(t) and not k.has(t): + r = l*log(x) if logx is None else l*logx + r += log(k) - l*log(cdir) # XXX true regardless of assumptions? + return r + + def coeff_exp(term, x): + coeff, exp = S.One, S.Zero + for factor in Mul.make_args(term): + if factor.has(x): + base, exp = factor.as_base_exp() + if base != x: + try: + return term.leadterm(x) + except ValueError: + return term, S.Zero + else: + coeff *= factor + return coeff, exp + + # TODO new and probably slow + try: + a, b = z.leadterm(t, logx=logx, cdir=1) + except (ValueError, NotImplementedError, PoleError): + s = z._eval_nseries(t, n=n, logx=logx, cdir=1) + while s.is_Order: + n += 1 + s = z._eval_nseries(t, n=n, logx=logx, cdir=1) + try: + a, b = s.removeO().leadterm(t, cdir=1) + except ValueError: + a, b = s.removeO().as_leading_term(t, cdir=1), S.Zero + + p = (z/(a*t**b) - 1).cancel()._eval_nseries(t, n=n, logx=logx, cdir=1) + if p.has(exp): + p = logcombine(p) + if isinstance(p, Order): + n = p.getn() + _, d = coeff_exp(p, t) + logx = log(x) if logx is None else logx + + if not d.is_positive: + res = log(a) - b*log(cdir) + b*logx + _res = res + logflags = {"deep": True, "log": True, "mul": False, "power_exp": False, + "power_base": False, "multinomial": False, "basic": False, "force": True, + "factor": False} + expr = self.expand(**logflags) + if (not a.could_extract_minus_sign() and + logx.could_extract_minus_sign()): + _res = _res.subs(-logx, -log(x)).expand(**logflags) + else: + _res = _res.subs(logx, log(x)).expand(**logflags) + if _res == expr: + return res + return res + Order(x**n, x) + + def mul(d1, d2): + res = {} + for e1, e2 in product(d1, d2): + ex = e1 + e2 + if ex < n: + res[ex] = res.get(ex, S.Zero) + d1[e1]*d2[e2] + return res + + pterms = {} + + for term in Add.make_args(p.removeO()): + co1, e1 = coeff_exp(term, t) + pterms[e1] = pterms.get(e1, S.Zero) + co1 + + k = S.One + terms = {} + pk = pterms + + while k*d < n: + coeff = -S.NegativeOne**k/k + for ex in pk: + terms[ex] = terms.get(ex, S.Zero) + coeff*pk[ex] + pk = mul(pk, pterms) + k += S.One + + res = log(a) - b*log(cdir) + b*logx + for ex in terms: + res += terms[ex].cancel()*t**(ex) + + if a.is_negative and im(z) != 0: + from sympy.functions.special.delta_functions import Heaviside + for i, term in enumerate(z.lseries(t)): + if not term.is_real or i == 5: + break + if i < 5: + coeff, _ = term.as_coeff_exponent(t) + res += -2*I*pi*Heaviside(-im(coeff), 0) + + res = res.subs(t, x/cdir) + return res + Order(x**n, x) + + def _eval_as_leading_term(self, x, logx, cdir): + # NOTE + # Refer https://github.com/sympy/sympy/pull/23592 for more information + # on each of the following steps involved in this method. + arg0 = self.args[0].together() + + # STEP 1 + t = Dummy('t', positive=True) + if cdir == 0: + cdir = 1 + z = arg0.subs(x, cdir*t) + + # STEP 2 + try: + c, e = z.leadterm(t, logx=logx, cdir=1) + except ValueError: + arg = arg0.as_leading_term(x, logx=logx, cdir=cdir) + return log(arg) + if c.has(t): + c = c.subs(t, x/cdir) + if e != 0: + raise PoleError("Cannot expand %s around 0" % (self)) + return log(c) + + # STEP 3 + if c == S.One and e == S.Zero: + return (arg0 - S.One).as_leading_term(x, logx=logx) + + # STEP 4 + res = log(c) - e*log(cdir) + logx = log(x) if logx is None else logx + res += e*logx + + # STEP 5 + if c.is_negative and im(z) != 0: + from sympy.functions.special.delta_functions import Heaviside + for i, term in enumerate(z.lseries(t)): + if not term.is_real or i == 5: + break + if i < 5: + coeff, _ = term.as_coeff_exponent(t) + res += -2*I*pi*Heaviside(-im(coeff), 0) + return res + + +class LambertW(DefinedFunction): + r""" + The Lambert W function $W(z)$ is defined as the inverse + function of $w \exp(w)$ [1]_. + + Explanation + =========== + + In other words, the value of $W(z)$ is such that $z = W(z) \exp(W(z))$ + for any complex number $z$. The Lambert W function is a multivalued + function with infinitely many branches $W_k(z)$, indexed by + $k \in \mathbb{Z}$. Each branch gives a different solution $w$ + of the equation $z = w \exp(w)$. + + The Lambert W function has two partially real branches: the + principal branch ($k = 0$) is real for real $z > -1/e$, and the + $k = -1$ branch is real for $-1/e < z < 0$. All branches except + $k = 0$ have a logarithmic singularity at $z = 0$. + + Examples + ======== + + >>> from sympy import LambertW + >>> LambertW(1.2) + 0.635564016364870 + >>> LambertW(1.2, -1).n() + -1.34747534407696 - 4.41624341514535*I + >>> LambertW(-1).is_real + False + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Lambert_W_function + """ + _singularities = (-Pow(S.Exp1, -1, evaluate=False), S.ComplexInfinity) + + @classmethod + def eval(cls, x, k=None): + if k == S.Zero: + return cls(x) + elif k is None: + k = S.Zero + + if k.is_zero: + if x.is_zero: + return S.Zero + if x is S.Exp1: + return S.One + if x == -1/S.Exp1: + return S.NegativeOne + if x == -log(2)/2: + return -log(2) + if x == 2*log(2): + return log(2) + if x == -pi/2: + return I*pi/2 + if x == exp(1 + S.Exp1): + return S.Exp1 + if x is S.Infinity: + return S.Infinity + + if fuzzy_not(k.is_zero): + if x.is_zero: + return S.NegativeInfinity + if k is S.NegativeOne: + if x == -pi/2: + return -I*pi/2 + elif x == -1/S.Exp1: + return S.NegativeOne + elif x == -2*exp(-2): + return -Integer(2) + + def fdiff(self, argindex=1): + """ + Return the first derivative of this function. + """ + x = self.args[0] + + if len(self.args) == 1: + if argindex == 1: + return LambertW(x)/(x*(1 + LambertW(x))) + else: + k = self.args[1] + if argindex == 1: + return LambertW(x, k)/(x*(1 + LambertW(x, k))) + + raise ArgumentIndexError(self, argindex) + + def _eval_is_extended_real(self): + x = self.args[0] + if len(self.args) == 1: + k = S.Zero + else: + k = self.args[1] + if k.is_zero: + if (x + 1/S.Exp1).is_positive: + return True + elif (x + 1/S.Exp1).is_nonpositive: + return False + elif (k + 1).is_zero: + if x.is_negative and (x + 1/S.Exp1).is_positive: + return True + elif x.is_nonpositive or (x + 1/S.Exp1).is_nonnegative: + return False + elif fuzzy_not(k.is_zero) and fuzzy_not((k + 1).is_zero): + if x.is_extended_real: + return False + + def _eval_is_finite(self): + return self.args[0].is_finite + + def _eval_is_algebraic(self): + s = self.func(*self.args) + if s.func == self.func: + if fuzzy_not(self.args[0].is_zero) and self.args[0].is_algebraic: + return False + else: + return s.is_algebraic + + def _eval_as_leading_term(self, x, logx, cdir): + if len(self.args) == 1: + arg = self.args[0] + arg0 = arg.subs(x, 0).cancel() + if not arg0.is_zero: + return self.func(arg0) + return arg.as_leading_term(x) + + def _eval_nseries(self, x, n, logx, cdir=0): + if len(self.args) == 1: + from sympy.functions.elementary.integers import ceiling + from sympy.series.order import Order + arg = self.args[0].nseries(x, n=n, logx=logx) + lt = arg.as_leading_term(x, logx=logx) + lte = 1 + if lt.is_Pow: + lte = lt.exp + if ceiling(n/lte) >= 1: + s = Add(*[(-S.One)**(k - 1)*Integer(k)**(k - 2)/ + factorial(k - 1)*arg**k for k in range(1, ceiling(n/lte))]) + s = expand_multinomial(s) + else: + s = S.Zero + + return s + Order(x**n, x) + return super()._eval_nseries(x, n, logx) + + def _eval_is_zero(self): + x = self.args[0] + if len(self.args) == 1: + return x.is_zero + else: + return fuzzy_and([x.is_zero, self.args[1].is_zero]) + + +@cacheit +def _log_atan_table(): + return { + # first quadrant only + sqrt(3): pi / 3, + 1: pi / 4, + sqrt(5 - 2 * sqrt(5)): pi / 5, + sqrt(2) * sqrt(5 - sqrt(5)) / (1 + sqrt(5)): pi / 5, + sqrt(5 + 2 * sqrt(5)): pi * Rational(2, 5), + sqrt(2) * sqrt(sqrt(5) + 5) / (-1 + sqrt(5)): pi * Rational(2, 5), + sqrt(3) / 3: pi / 6, + sqrt(2) - 1: pi / 8, + sqrt(2 - sqrt(2)) / sqrt(sqrt(2) + 2): pi / 8, + sqrt(2) + 1: pi * Rational(3, 8), + sqrt(sqrt(2) + 2) / sqrt(2 - sqrt(2)): pi * Rational(3, 8), + sqrt(1 - 2 * sqrt(5) / 5): pi / 10, + (-sqrt(2) + sqrt(10)) / (2 * sqrt(sqrt(5) + 5)): pi / 10, + sqrt(1 + 2 * sqrt(5) / 5): pi * Rational(3, 10), + (sqrt(2) + sqrt(10)) / (2 * sqrt(5 - sqrt(5))): pi * Rational(3, 10), + 2 - sqrt(3): pi / 12, + (-1 + sqrt(3)) / (1 + sqrt(3)): pi / 12, + 2 + sqrt(3): pi * Rational(5, 12), + (1 + sqrt(3)) / (-1 + sqrt(3)): pi * Rational(5, 12) + } diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/hyperbolic.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/hyperbolic.py new file mode 100644 index 0000000000000000000000000000000000000000..1031d035373bb641d26e61a395e6048906285bfe --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/hyperbolic.py @@ -0,0 +1,2285 @@ +from sympy.core import S, sympify, cacheit +from sympy.core.add import Add +from sympy.core.function import DefinedFunction, ArgumentIndexError +from sympy.core.logic import fuzzy_or, fuzzy_and, fuzzy_not, FuzzyBool +from sympy.core.numbers import I, pi, Rational +from sympy.core.symbol import Dummy +from sympy.functions.combinatorial.factorials import (binomial, factorial, + RisingFactorial) +from sympy.functions.combinatorial.numbers import bernoulli, euler, nC +from sympy.functions.elementary.complexes import Abs, im, re +from sympy.functions.elementary.exponential import exp, log, match_real_imag +from sympy.functions.elementary.integers import floor +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import ( + acos, acot, asin, atan, cos, cot, csc, sec, sin, tan, + _imaginary_unit_as_coefficient) +from sympy.polys.specialpolys import symmetric_poly + + +def _rewrite_hyperbolics_as_exp(expr): + return expr.xreplace({h: h.rewrite(exp) + for h in expr.atoms(HyperbolicFunction)}) + + +@cacheit +def _acosh_table(): + return { + I: log(I*(1 + sqrt(2))), + -I: log(-I*(1 + sqrt(2))), + S.Half: pi/3, + Rational(-1, 2): pi*Rational(2, 3), + sqrt(2)/2: pi/4, + -sqrt(2)/2: pi*Rational(3, 4), + 1/sqrt(2): pi/4, + -1/sqrt(2): pi*Rational(3, 4), + sqrt(3)/2: pi/6, + -sqrt(3)/2: pi*Rational(5, 6), + (sqrt(3) - 1)/sqrt(2**3): pi*Rational(5, 12), + -(sqrt(3) - 1)/sqrt(2**3): pi*Rational(7, 12), + sqrt(2 + sqrt(2))/2: pi/8, + -sqrt(2 + sqrt(2))/2: pi*Rational(7, 8), + sqrt(2 - sqrt(2))/2: pi*Rational(3, 8), + -sqrt(2 - sqrt(2))/2: pi*Rational(5, 8), + (1 + sqrt(3))/(2*sqrt(2)): pi/12, + -(1 + sqrt(3))/(2*sqrt(2)): pi*Rational(11, 12), + (sqrt(5) + 1)/4: pi/5, + -(sqrt(5) + 1)/4: pi*Rational(4, 5) + } + + +@cacheit +def _acsch_table(): + return { + I: -pi / 2, + I*(sqrt(2) + sqrt(6)): -pi / 12, + I*(1 + sqrt(5)): -pi / 10, + I*2 / sqrt(2 - sqrt(2)): -pi / 8, + I*2: -pi / 6, + I*sqrt(2 + 2/sqrt(5)): -pi / 5, + I*sqrt(2): -pi / 4, + I*(sqrt(5)-1): -3*pi / 10, + I*2 / sqrt(3): -pi / 3, + I*2 / sqrt(2 + sqrt(2)): -3*pi / 8, + I*sqrt(2 - 2/sqrt(5)): -2*pi / 5, + I*(sqrt(6) - sqrt(2)): -5*pi / 12, + S(2): -I*log((1+sqrt(5))/2), + } + + +@cacheit +def _asech_table(): + return { + I: - (pi*I / 2) + log(1 + sqrt(2)), + -I: (pi*I / 2) + log(1 + sqrt(2)), + (sqrt(6) - sqrt(2)): pi / 12, + (sqrt(2) - sqrt(6)): 11*pi / 12, + sqrt(2 - 2/sqrt(5)): pi / 10, + -sqrt(2 - 2/sqrt(5)): 9*pi / 10, + 2 / sqrt(2 + sqrt(2)): pi / 8, + -2 / sqrt(2 + sqrt(2)): 7*pi / 8, + 2 / sqrt(3): pi / 6, + -2 / sqrt(3): 5*pi / 6, + (sqrt(5) - 1): pi / 5, + (1 - sqrt(5)): 4*pi / 5, + sqrt(2): pi / 4, + -sqrt(2): 3*pi / 4, + sqrt(2 + 2/sqrt(5)): 3*pi / 10, + -sqrt(2 + 2/sqrt(5)): 7*pi / 10, + S(2): pi / 3, + -S(2): 2*pi / 3, + sqrt(2*(2 + sqrt(2))): 3*pi / 8, + -sqrt(2*(2 + sqrt(2))): 5*pi / 8, + (1 + sqrt(5)): 2*pi / 5, + (-1 - sqrt(5)): 3*pi / 5, + (sqrt(6) + sqrt(2)): 5*pi / 12, + (-sqrt(6) - sqrt(2)): 7*pi / 12, + I*S.Infinity: -pi*I / 2, + I*S.NegativeInfinity: pi*I / 2, + } + +############################################################################### +########################### HYPERBOLIC FUNCTIONS ############################## +############################################################################### + + +class HyperbolicFunction(DefinedFunction): + """ + Base class for hyperbolic functions. + + See Also + ======== + + sinh, cosh, tanh, coth + """ + + unbranched = True + + +def _peeloff_ipi(arg): + r""" + Split ARG into two parts, a "rest" and a multiple of $I\pi$. + This assumes ARG to be an ``Add``. + The multiple of $I\pi$ returned in the second position is always a ``Rational``. + + Examples + ======== + + >>> from sympy.functions.elementary.hyperbolic import _peeloff_ipi as peel + >>> from sympy import pi, I + >>> from sympy.abc import x, y + >>> peel(x + I*pi/2) + (x, 1/2) + >>> peel(x + I*2*pi/3 + I*pi*y) + (x + I*pi*y + I*pi/6, 1/2) + """ + ipi = pi*I + for a in Add.make_args(arg): + if a == ipi: + K = S.One + break + elif a.is_Mul: + K, p = a.as_two_terms() + if p == ipi and K.is_Rational: + break + else: + return arg, S.Zero + + m1 = (K % S.Half) + m2 = K - m1 + return arg - m2*ipi, m2 + + +class sinh(HyperbolicFunction): + r""" + ``sinh(x)`` is the hyperbolic sine of ``x``. + + The hyperbolic sine function is $\frac{e^x - e^{-x}}{2}$. + + Examples + ======== + + >>> from sympy import sinh + >>> from sympy.abc import x + >>> sinh(x) + sinh(x) + + See Also + ======== + + cosh, tanh, asinh + """ + + def fdiff(self, argindex=1): + """ + Returns the first derivative of this function. + """ + if argindex == 1: + return cosh(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return asinh + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Infinity + elif arg is S.NegativeInfinity: + return S.NegativeInfinity + elif arg.is_zero: + return S.Zero + elif arg.is_negative: + return -cls(-arg) + else: + if arg is S.ComplexInfinity: + return S.NaN + + i_coeff = _imaginary_unit_as_coefficient(arg) + + if i_coeff is not None: + return I * sin(i_coeff) + else: + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if arg.is_Add: + x, m = _peeloff_ipi(arg) + if m: + m = m*pi*I + return sinh(m)*cosh(x) + cosh(m)*sinh(x) + + if arg.is_zero: + return S.Zero + + if arg.func == asinh: + return arg.args[0] + + if arg.func == acosh: + x = arg.args[0] + return sqrt(x - 1) * sqrt(x + 1) + + if arg.func == atanh: + x = arg.args[0] + return x/sqrt(1 - x**2) + + if arg.func == acoth: + x = arg.args[0] + return 1/(sqrt(x - 1) * sqrt(x + 1)) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + """ + Returns the next term in the Taylor series expansion. + """ + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + + if len(previous_terms) > 2: + p = previous_terms[-2] + return p * x**2 / (n*(n - 1)) + else: + return x**(n) / factorial(n) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def as_real_imag(self, deep=True, **hints): + """ + Returns this function as a complex coordinate. + """ + if self.args[0].is_extended_real: + if deep: + hints['complex'] = False + return (self.expand(deep, **hints), S.Zero) + else: + return (self, S.Zero) + if deep: + re, im = self.args[0].expand(deep, **hints).as_real_imag() + else: + re, im = self.args[0].as_real_imag() + return (sinh(re)*cos(im), cosh(re)*sin(im)) + + def _eval_expand_complex(self, deep=True, **hints): + re_part, im_part = self.as_real_imag(deep=deep, **hints) + return re_part + im_part*I + + def _eval_expand_trig(self, deep=True, **hints): + if deep: + arg = self.args[0].expand(deep, **hints) + else: + arg = self.args[0] + x = None + if arg.is_Add: # TODO, implement more if deep stuff here + x, y = arg.as_two_terms() + else: + coeff, terms = arg.as_coeff_Mul(rational=True) + if coeff is not S.One and coeff.is_Integer and terms is not S.One: + x = terms + y = (coeff - 1)*x + if x is not None: + return (sinh(x)*cosh(y) + sinh(y)*cosh(x)).expand(trig=True) + return sinh(arg) + + def _eval_rewrite_as_tractable(self, arg, limitvar=None, **kwargs): + return (exp(arg) - exp(-arg)) / 2 + + def _eval_rewrite_as_exp(self, arg, **kwargs): + return (exp(arg) - exp(-arg)) / 2 + + def _eval_rewrite_as_sin(self, arg, **kwargs): + return -I * sin(I * arg) + + def _eval_rewrite_as_csc(self, arg, **kwargs): + return -I / csc(I * arg) + + def _eval_rewrite_as_cosh(self, arg, **kwargs): + return -I*cosh(arg + pi*I/2) + + def _eval_rewrite_as_tanh(self, arg, **kwargs): + tanh_half = tanh(S.Half*arg) + return 2*tanh_half/(1 - tanh_half**2) + + def _eval_rewrite_as_coth(self, arg, **kwargs): + coth_half = coth(S.Half*arg) + return 2*coth_half/(coth_half**2 - 1) + + def _eval_rewrite_as_csch(self, arg, **kwargs): + return 1 / csch(arg) + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if arg0 is S.NaN: + arg0 = arg.limit(x, 0, dir='-' if cdir.is_negative else '+') + if arg0.is_zero: + return arg + elif arg0.is_finite: + return self.func(arg0) + else: + return self + + def _eval_is_real(self): + arg = self.args[0] + if arg.is_real: + return True + + # if `im` is of the form n*pi + # else, check if it is a number + re, im = arg.as_real_imag() + return (im%pi).is_zero + + def _eval_is_extended_real(self): + if self.args[0].is_extended_real: + return True + + def _eval_is_positive(self): + if self.args[0].is_extended_real: + return self.args[0].is_positive + + def _eval_is_negative(self): + if self.args[0].is_extended_real: + return self.args[0].is_negative + + def _eval_is_finite(self): + arg = self.args[0] + return arg.is_finite + + def _eval_is_zero(self): + rest, ipi_mult = _peeloff_ipi(self.args[0]) + if rest.is_zero: + return ipi_mult.is_integer + + +class cosh(HyperbolicFunction): + r""" + ``cosh(x)`` is the hyperbolic cosine of ``x``. + + The hyperbolic cosine function is $\frac{e^x + e^{-x}}{2}$. + + Examples + ======== + + >>> from sympy import cosh + >>> from sympy.abc import x + >>> cosh(x) + cosh(x) + + See Also + ======== + + sinh, tanh, acosh + """ + + def fdiff(self, argindex=1): + if argindex == 1: + return sinh(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + from sympy.functions.elementary.trigonometric import cos + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Infinity + elif arg is S.NegativeInfinity: + return S.Infinity + elif arg.is_zero: + return S.One + elif arg.is_negative: + return cls(-arg) + else: + if arg is S.ComplexInfinity: + return S.NaN + + i_coeff = _imaginary_unit_as_coefficient(arg) + + if i_coeff is not None: + return cos(i_coeff) + else: + if arg.could_extract_minus_sign(): + return cls(-arg) + + if arg.is_Add: + x, m = _peeloff_ipi(arg) + if m: + m = m*pi*I + return cosh(m)*cosh(x) + sinh(m)*sinh(x) + + if arg.is_zero: + return S.One + + if arg.func == asinh: + return sqrt(1 + arg.args[0]**2) + + if arg.func == acosh: + return arg.args[0] + + if arg.func == atanh: + return 1/sqrt(1 - arg.args[0]**2) + + if arg.func == acoth: + x = arg.args[0] + return x/(sqrt(x - 1) * sqrt(x + 1)) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 1: + return S.Zero + else: + x = sympify(x) + + if len(previous_terms) > 2: + p = previous_terms[-2] + return p * x**2 / (n*(n - 1)) + else: + return x**(n)/factorial(n) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def as_real_imag(self, deep=True, **hints): + if self.args[0].is_extended_real: + if deep: + hints['complex'] = False + return (self.expand(deep, **hints), S.Zero) + else: + return (self, S.Zero) + if deep: + re, im = self.args[0].expand(deep, **hints).as_real_imag() + else: + re, im = self.args[0].as_real_imag() + + return (cosh(re)*cos(im), sinh(re)*sin(im)) + + def _eval_expand_complex(self, deep=True, **hints): + re_part, im_part = self.as_real_imag(deep=deep, **hints) + return re_part + im_part*I + + def _eval_expand_trig(self, deep=True, **hints): + if deep: + arg = self.args[0].expand(deep, **hints) + else: + arg = self.args[0] + x = None + if arg.is_Add: # TODO, implement more if deep stuff here + x, y = arg.as_two_terms() + else: + coeff, terms = arg.as_coeff_Mul(rational=True) + if coeff is not S.One and coeff.is_Integer and terms is not S.One: + x = terms + y = (coeff - 1)*x + if x is not None: + return (cosh(x)*cosh(y) + sinh(x)*sinh(y)).expand(trig=True) + return cosh(arg) + + def _eval_rewrite_as_tractable(self, arg, limitvar=None, **kwargs): + return (exp(arg) + exp(-arg)) / 2 + + def _eval_rewrite_as_exp(self, arg, **kwargs): + return (exp(arg) + exp(-arg)) / 2 + + def _eval_rewrite_as_cos(self, arg, **kwargs): + return cos(I * arg, evaluate=False) + + def _eval_rewrite_as_sec(self, arg, **kwargs): + return 1 / sec(I * arg, evaluate=False) + + def _eval_rewrite_as_sinh(self, arg, **kwargs): + return -I*sinh(arg + pi*I/2, evaluate=False) + + def _eval_rewrite_as_tanh(self, arg, **kwargs): + tanh_half = tanh(S.Half*arg)**2 + return (1 + tanh_half)/(1 - tanh_half) + + def _eval_rewrite_as_coth(self, arg, **kwargs): + coth_half = coth(S.Half*arg)**2 + return (coth_half + 1)/(coth_half - 1) + + def _eval_rewrite_as_sech(self, arg, **kwargs): + return 1 / sech(arg) + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if arg0 is S.NaN: + arg0 = arg.limit(x, 0, dir='-' if cdir.is_negative else '+') + if arg0.is_zero: + return S.One + elif arg0.is_finite: + return self.func(arg0) + else: + return self + + def _eval_is_real(self): + arg = self.args[0] + + # `cosh(x)` is real for real OR purely imaginary `x` + if arg.is_real or arg.is_imaginary: + return True + + # cosh(a+ib) = cos(b)*cosh(a) + i*sin(b)*sinh(a) + # the imaginary part can be an expression like n*pi + # if not, check if the imaginary part is a number + re, im = arg.as_real_imag() + return (im%pi).is_zero + + def _eval_is_positive(self): + # cosh(x+I*y) = cos(y)*cosh(x) + I*sin(y)*sinh(x) + # cosh(z) is positive iff it is real and the real part is positive. + # So we need sin(y)*sinh(x) = 0 which gives x=0 or y=n*pi + # Case 1 (y=n*pi): cosh(z) = (-1)**n * cosh(x) -> positive for n even + # Case 2 (x=0): cosh(z) = cos(y) -> positive when cos(y) is positive + z = self.args[0] + + x, y = z.as_real_imag() + ymod = y % (2*pi) + + yzero = ymod.is_zero + # shortcut if ymod is zero + if yzero: + return True + + xzero = x.is_zero + # shortcut x is not zero + if xzero is False: + return yzero + + return fuzzy_or([ + # Case 1: + yzero, + # Case 2: + fuzzy_and([ + xzero, + fuzzy_or([ymod < pi/2, ymod > 3*pi/2]) + ]) + ]) + + + def _eval_is_nonnegative(self): + z = self.args[0] + + x, y = z.as_real_imag() + ymod = y % (2*pi) + + yzero = ymod.is_zero + # shortcut if ymod is zero + if yzero: + return True + + xzero = x.is_zero + # shortcut x is not zero + if xzero is False: + return yzero + + return fuzzy_or([ + # Case 1: + yzero, + # Case 2: + fuzzy_and([ + xzero, + fuzzy_or([ymod <= pi/2, ymod >= 3*pi/2]) + ]) + ]) + + def _eval_is_finite(self): + arg = self.args[0] + return arg.is_finite + + def _eval_is_zero(self): + rest, ipi_mult = _peeloff_ipi(self.args[0]) + if ipi_mult and rest.is_zero: + return (ipi_mult - S.Half).is_integer + + +class tanh(HyperbolicFunction): + r""" + ``tanh(x)`` is the hyperbolic tangent of ``x``. + + The hyperbolic tangent function is $\frac{\sinh(x)}{\cosh(x)}$. + + Examples + ======== + + >>> from sympy import tanh + >>> from sympy.abc import x + >>> tanh(x) + tanh(x) + + See Also + ======== + + sinh, cosh, atanh + """ + + def fdiff(self, argindex=1): + if argindex == 1: + return S.One - tanh(self.args[0])**2 + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return atanh + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.One + elif arg is S.NegativeInfinity: + return S.NegativeOne + elif arg.is_zero: + return S.Zero + elif arg.is_negative: + return -cls(-arg) + else: + if arg is S.ComplexInfinity: + return S.NaN + + i_coeff = _imaginary_unit_as_coefficient(arg) + + if i_coeff is not None: + if i_coeff.could_extract_minus_sign(): + return -I * tan(-i_coeff) + return I * tan(i_coeff) + else: + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if arg.is_Add: + x, m = _peeloff_ipi(arg) + if m: + tanhm = tanh(m*pi*I) + if tanhm is S.ComplexInfinity: + return coth(x) + else: # tanhm == 0 + return tanh(x) + + if arg.is_zero: + return S.Zero + + if arg.func == asinh: + x = arg.args[0] + return x/sqrt(1 + x**2) + + if arg.func == acosh: + x = arg.args[0] + return sqrt(x - 1) * sqrt(x + 1) / x + + if arg.func == atanh: + return arg.args[0] + + if arg.func == acoth: + return 1/arg.args[0] + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + + a = 2**(n + 1) + + B = bernoulli(n + 1) + F = factorial(n + 1) + + return a*(a - 1) * B/F * x**n + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def as_real_imag(self, deep=True, **hints): + if self.args[0].is_extended_real: + if deep: + hints['complex'] = False + return (self.expand(deep, **hints), S.Zero) + else: + return (self, S.Zero) + if deep: + re, im = self.args[0].expand(deep, **hints).as_real_imag() + else: + re, im = self.args[0].as_real_imag() + denom = sinh(re)**2 + cos(im)**2 + return (sinh(re)*cosh(re)/denom, sin(im)*cos(im)/denom) + + def _eval_expand_trig(self, **hints): + arg = self.args[0] + if arg.is_Add: + n = len(arg.args) + TX = [tanh(x, evaluate=False)._eval_expand_trig() + for x in arg.args] + p = [0, 0] # [den, num] + for i in range(n + 1): + p[i % 2] += symmetric_poly(i, TX) + return p[1]/p[0] + elif arg.is_Mul: + coeff, terms = arg.as_coeff_Mul() + if coeff.is_Integer and coeff > 1: + T = tanh(terms) + n = [nC(range(coeff), k)*T**k for k in range(1, coeff + 1, 2)] + d = [nC(range(coeff), k)*T**k for k in range(0, coeff + 1, 2)] + return Add(*n)/Add(*d) + return tanh(arg) + + def _eval_rewrite_as_tractable(self, arg, limitvar=None, **kwargs): + neg_exp, pos_exp = exp(-arg), exp(arg) + return (pos_exp - neg_exp)/(pos_exp + neg_exp) + + def _eval_rewrite_as_exp(self, arg, **kwargs): + neg_exp, pos_exp = exp(-arg), exp(arg) + return (pos_exp - neg_exp)/(pos_exp + neg_exp) + + def _eval_rewrite_as_tan(self, arg, **kwargs): + return -I * tan(I * arg, evaluate=False) + + def _eval_rewrite_as_cot(self, arg, **kwargs): + return -I / cot(I * arg, evaluate=False) + + def _eval_rewrite_as_sinh(self, arg, **kwargs): + return I*sinh(arg)/sinh(pi*I/2 - arg, evaluate=False) + + def _eval_rewrite_as_cosh(self, arg, **kwargs): + return I*cosh(pi*I/2 - arg, evaluate=False)/cosh(arg) + + def _eval_rewrite_as_coth(self, arg, **kwargs): + return 1/coth(arg) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.series.order import Order + arg = self.args[0].as_leading_term(x) + + if x in arg.free_symbols and Order(1, x).contains(arg): + return arg + else: + return self.func(arg) + + def _eval_is_real(self): + arg = self.args[0] + if arg.is_real: + return True + + re, im = arg.as_real_imag() + + # if denom = 0, tanh(arg) = zoo + if re == 0 and im % pi == pi/2: + return None + + # check if im is of the form n*pi/2 to make sin(2*im) = 0 + # if not, im could be a number, return False in that case + return (im % (pi/2)).is_zero + + def _eval_is_extended_real(self): + if self.args[0].is_extended_real: + return True + + def _eval_is_positive(self): + if self.args[0].is_extended_real: + return self.args[0].is_positive + + def _eval_is_negative(self): + if self.args[0].is_extended_real: + return self.args[0].is_negative + + def _eval_is_finite(self): + arg = self.args[0] + + re, im = arg.as_real_imag() + denom = cos(im)**2 + sinh(re)**2 + if denom == 0: + return False + elif denom.is_number: + return True + if arg.is_extended_real: + return True + + def _eval_is_zero(self): + arg = self.args[0] + if arg.is_zero: + return True + + +class coth(HyperbolicFunction): + r""" + ``coth(x)`` is the hyperbolic cotangent of ``x``. + + The hyperbolic cotangent function is $\frac{\cosh(x)}{\sinh(x)}$. + + Examples + ======== + + >>> from sympy import coth + >>> from sympy.abc import x + >>> coth(x) + coth(x) + + See Also + ======== + + sinh, cosh, acoth + """ + + def fdiff(self, argindex=1): + if argindex == 1: + return -1/sinh(self.args[0])**2 + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return acoth + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.One + elif arg is S.NegativeInfinity: + return S.NegativeOne + elif arg.is_zero: + return S.ComplexInfinity + elif arg.is_negative: + return -cls(-arg) + else: + if arg is S.ComplexInfinity: + return S.NaN + + i_coeff = _imaginary_unit_as_coefficient(arg) + + if i_coeff is not None: + if i_coeff.could_extract_minus_sign(): + return I * cot(-i_coeff) + return -I * cot(i_coeff) + else: + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if arg.is_Add: + x, m = _peeloff_ipi(arg) + if m: + cothm = coth(m*pi*I) + if cothm is S.ComplexInfinity: + return coth(x) + else: # cothm == 0 + return tanh(x) + + if arg.is_zero: + return S.ComplexInfinity + + if arg.func == asinh: + x = arg.args[0] + return sqrt(1 + x**2)/x + + if arg.func == acosh: + x = arg.args[0] + return x/(sqrt(x - 1) * sqrt(x + 1)) + + if arg.func == atanh: + return 1/arg.args[0] + + if arg.func == acoth: + return arg.args[0] + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return 1 / sympify(x) + elif n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + + B = bernoulli(n + 1) + F = factorial(n + 1) + + return 2**(n + 1) * B/F * x**n + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def as_real_imag(self, deep=True, **hints): + from sympy.functions.elementary.trigonometric import (cos, sin) + if self.args[0].is_extended_real: + if deep: + hints['complex'] = False + return (self.expand(deep, **hints), S.Zero) + else: + return (self, S.Zero) + if deep: + re, im = self.args[0].expand(deep, **hints).as_real_imag() + else: + re, im = self.args[0].as_real_imag() + denom = sinh(re)**2 + sin(im)**2 + return (sinh(re)*cosh(re)/denom, -sin(im)*cos(im)/denom) + + def _eval_rewrite_as_tractable(self, arg, limitvar=None, **kwargs): + neg_exp, pos_exp = exp(-arg), exp(arg) + return (pos_exp + neg_exp)/(pos_exp - neg_exp) + + def _eval_rewrite_as_exp(self, arg, **kwargs): + neg_exp, pos_exp = exp(-arg), exp(arg) + return (pos_exp + neg_exp)/(pos_exp - neg_exp) + + def _eval_rewrite_as_sinh(self, arg, **kwargs): + return -I*sinh(pi*I/2 - arg, evaluate=False)/sinh(arg) + + def _eval_rewrite_as_cosh(self, arg, **kwargs): + return -I*cosh(arg)/cosh(pi*I/2 - arg, evaluate=False) + + def _eval_rewrite_as_tanh(self, arg, **kwargs): + return 1/tanh(arg) + + def _eval_is_positive(self): + if self.args[0].is_extended_real: + return self.args[0].is_positive + + def _eval_is_negative(self): + if self.args[0].is_extended_real: + return self.args[0].is_negative + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.series.order import Order + arg = self.args[0].as_leading_term(x) + + if x in arg.free_symbols and Order(1, x).contains(arg): + return 1/arg + else: + return self.func(arg) + + def _eval_expand_trig(self, **hints): + arg = self.args[0] + if arg.is_Add: + CX = [coth(x, evaluate=False)._eval_expand_trig() for x in arg.args] + p = [[], []] + n = len(arg.args) + for i in range(n, -1, -1): + p[(n - i) % 2].append(symmetric_poly(i, CX)) + return Add(*p[0])/Add(*p[1]) + elif arg.is_Mul: + coeff, x = arg.as_coeff_Mul(rational=True) + if coeff.is_Integer and coeff > 1: + c = coth(x, evaluate=False) + p = [[], []] + for i in range(coeff, -1, -1): + p[(coeff - i) % 2].append(binomial(coeff, i)*c**i) + return Add(*p[0])/Add(*p[1]) + return coth(arg) + + +class ReciprocalHyperbolicFunction(HyperbolicFunction): + """Base class for reciprocal functions of hyperbolic functions. """ + + #To be defined in class + _reciprocal_of = None + _is_even: FuzzyBool = None + _is_odd: FuzzyBool = None + + @classmethod + def eval(cls, arg): + if arg.could_extract_minus_sign(): + if cls._is_even: + return cls(-arg) + if cls._is_odd: + return -cls(-arg) + + t = cls._reciprocal_of.eval(arg) + if hasattr(arg, 'inverse') and arg.inverse() == cls: + return arg.args[0] + return 1/t if t is not None else t + + def _call_reciprocal(self, method_name, *args, **kwargs): + # Calls method_name on _reciprocal_of + o = self._reciprocal_of(self.args[0]) + return getattr(o, method_name)(*args, **kwargs) + + def _calculate_reciprocal(self, method_name, *args, **kwargs): + # If calling method_name on _reciprocal_of returns a value != None + # then return the reciprocal of that value + t = self._call_reciprocal(method_name, *args, **kwargs) + return 1/t if t is not None else t + + def _rewrite_reciprocal(self, method_name, arg): + # Special handling for rewrite functions. If reciprocal rewrite returns + # unmodified expression, then return None + t = self._call_reciprocal(method_name, arg) + if t is not None and t != self._reciprocal_of(arg): + return 1/t + + def _eval_rewrite_as_exp(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_exp", arg) + + def _eval_rewrite_as_tractable(self, arg, limitvar=None, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_tractable", arg) + + def _eval_rewrite_as_tanh(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_tanh", arg) + + def _eval_rewrite_as_coth(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_coth", arg) + + def as_real_imag(self, deep = True, **hints): + return (1 / self._reciprocal_of(self.args[0])).as_real_imag(deep, **hints) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def _eval_expand_complex(self, deep=True, **hints): + re_part, im_part = self.as_real_imag(deep=True, **hints) + return re_part + I*im_part + + def _eval_expand_trig(self, **hints): + return self._calculate_reciprocal("_eval_expand_trig", **hints) + + def _eval_as_leading_term(self, x, logx, cdir): + return (1/self._reciprocal_of(self.args[0]))._eval_as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_is_extended_real(self): + return self._reciprocal_of(self.args[0]).is_extended_real + + def _eval_is_finite(self): + return (1/self._reciprocal_of(self.args[0])).is_finite + + +class csch(ReciprocalHyperbolicFunction): + r""" + ``csch(x)`` is the hyperbolic cosecant of ``x``. + + The hyperbolic cosecant function is $\frac{2}{e^x - e^{-x}}$ + + Examples + ======== + + >>> from sympy import csch + >>> from sympy.abc import x + >>> csch(x) + csch(x) + + See Also + ======== + + sinh, cosh, tanh, sech, asinh, acosh + """ + + _reciprocal_of = sinh + _is_odd = True + + def fdiff(self, argindex=1): + """ + Returns the first derivative of this function + """ + if argindex == 1: + return -coth(self.args[0]) * csch(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + """ + Returns the next term in the Taylor series expansion + """ + if n == 0: + return 1/sympify(x) + elif n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + + B = bernoulli(n + 1) + F = factorial(n + 1) + + return 2 * (1 - 2**n) * B/F * x**n + + def _eval_rewrite_as_sin(self, arg, **kwargs): + return I / sin(I * arg, evaluate=False) + + def _eval_rewrite_as_csc(self, arg, **kwargs): + return I * csc(I * arg, evaluate=False) + + def _eval_rewrite_as_cosh(self, arg, **kwargs): + return I / cosh(arg + I * pi / 2, evaluate=False) + + def _eval_rewrite_as_sinh(self, arg, **kwargs): + return 1 / sinh(arg) + + def _eval_is_positive(self): + if self.args[0].is_extended_real: + return self.args[0].is_positive + + def _eval_is_negative(self): + if self.args[0].is_extended_real: + return self.args[0].is_negative + + +class sech(ReciprocalHyperbolicFunction): + r""" + ``sech(x)`` is the hyperbolic secant of ``x``. + + The hyperbolic secant function is $\frac{2}{e^x + e^{-x}}$ + + Examples + ======== + + >>> from sympy import sech + >>> from sympy.abc import x + >>> sech(x) + sech(x) + + See Also + ======== + + sinh, cosh, tanh, coth, csch, asinh, acosh + """ + + _reciprocal_of = cosh + _is_even = True + + def fdiff(self, argindex=1): + if argindex == 1: + return - tanh(self.args[0])*sech(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 1: + return S.Zero + else: + x = sympify(x) + return euler(n) / factorial(n) * x**(n) + + def _eval_rewrite_as_cos(self, arg, **kwargs): + return 1 / cos(I * arg, evaluate=False) + + def _eval_rewrite_as_sec(self, arg, **kwargs): + return sec(I * arg, evaluate=False) + + def _eval_rewrite_as_sinh(self, arg, **kwargs): + return I / sinh(arg + I * pi /2, evaluate=False) + + def _eval_rewrite_as_cosh(self, arg, **kwargs): + return 1 / cosh(arg) + + def _eval_is_positive(self): + if self.args[0].is_extended_real: + return True + + +############################################################################### +############################# HYPERBOLIC INVERSES ############################# +############################################################################### + +class InverseHyperbolicFunction(DefinedFunction): + """Base class for inverse hyperbolic functions.""" + + pass + + +class asinh(InverseHyperbolicFunction): + """ + ``asinh(x)`` is the inverse hyperbolic sine of ``x``. + + The inverse hyperbolic sine function. + + Examples + ======== + + >>> from sympy import asinh + >>> from sympy.abc import x + >>> asinh(x).diff(x) + 1/sqrt(x**2 + 1) + >>> asinh(1) + log(1 + sqrt(2)) + + See Also + ======== + + acosh, atanh, sinh + """ + + def fdiff(self, argindex=1): + if argindex == 1: + return 1/sqrt(self.args[0]**2 + 1) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Infinity + elif arg is S.NegativeInfinity: + return S.NegativeInfinity + elif arg.is_zero: + return S.Zero + elif arg is S.One: + return log(sqrt(2) + 1) + elif arg is S.NegativeOne: + return log(sqrt(2) - 1) + elif arg.is_negative: + return -cls(-arg) + else: + if arg is S.ComplexInfinity: + return S.ComplexInfinity + + if arg.is_zero: + return S.Zero + + i_coeff = _imaginary_unit_as_coefficient(arg) + + if i_coeff is not None: + return I * asin(i_coeff) + else: + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if isinstance(arg, sinh) and arg.args[0].is_number: + z = arg.args[0] + if z.is_real: + return z + r, i = match_real_imag(z) + if r is not None and i is not None: + f = floor((i + pi/2)/pi) + m = z - I*pi*f + even = f.is_even + if even is True: + return m + elif even is False: + return -m + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) >= 2 and n > 2: + p = previous_terms[-2] + return -p * (n - 2)**2/(n*(n - 1)) * x**2 + else: + k = (n - 1) // 2 + R = RisingFactorial(S.Half, k) + F = factorial(k) + return S.NegativeOne**k * R / F * x**n / n + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + if x0.is_zero: + return arg.as_leading_term(x) + + if x0 is S.NaN: + expr = self.func(arg.as_leading_term(x)) + if expr.is_finite: + return expr + else: + return self + + # Handling branch points + if x0 in (-I, I, S.ComplexInfinity): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + # Handling points lying on branch cuts (-I*oo, -I) U (I, I*oo) + if (1 + x0**2).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if re(ndir).is_positive: + if im(x0).is_negative: + return -self.func(x0) - I*pi + elif re(ndir).is_negative: + if im(x0).is_positive: + return -self.func(x0) + I*pi + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # asinh + arg = self.args[0] + arg0 = arg.subs(x, 0) + + # Handling branch points + if arg0 in (I, -I): + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + + # Handling points lying on branch cuts (-I*oo, -I) U (I, I*oo) + if (1 + arg0**2).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if re(ndir).is_positive: + if im(arg0).is_negative: + return -res - I*pi + elif re(ndir).is_negative: + if im(arg0).is_positive: + return -res + I*pi + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_rewrite_as_log(self, x, **kwargs): + return log(x + sqrt(x**2 + 1)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_atanh(self, x, **kwargs): + return atanh(x/sqrt(1 + x**2)) + + def _eval_rewrite_as_acosh(self, x, **kwargs): + ix = I*x + return I*(sqrt(1 - ix)/sqrt(ix - 1) * acosh(ix) - pi/2) + + def _eval_rewrite_as_asin(self, x, **kwargs): + return -I * asin(I * x, evaluate=False) + + def _eval_rewrite_as_acos(self, x, **kwargs): + return I * acos(I * x, evaluate=False) - I*pi/2 + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return sinh + + def _eval_is_zero(self): + return self.args[0].is_zero + + def _eval_is_extended_real(self): + return self.args[0].is_extended_real + + def _eval_is_finite(self): + return self.args[0].is_finite + + +class acosh(InverseHyperbolicFunction): + """ + ``acosh(x)`` is the inverse hyperbolic cosine of ``x``. + + The inverse hyperbolic cosine function. + + Examples + ======== + + >>> from sympy import acosh + >>> from sympy.abc import x + >>> acosh(x).diff(x) + 1/(sqrt(x - 1)*sqrt(x + 1)) + >>> acosh(1) + 0 + + See Also + ======== + + asinh, atanh, cosh + """ + + def fdiff(self, argindex=1): + if argindex == 1: + arg = self.args[0] + return 1/(sqrt(arg - 1)*sqrt(arg + 1)) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Infinity + elif arg is S.NegativeInfinity: + return S.Infinity + elif arg.is_zero: + return pi*I / 2 + elif arg is S.One: + return S.Zero + elif arg is S.NegativeOne: + return pi*I + + if arg.is_number: + cst_table = _acosh_table() + + if arg in cst_table: + if arg.is_extended_real: + return cst_table[arg]*I + return cst_table[arg] + + if arg is S.ComplexInfinity: + return S.ComplexInfinity + if arg == I*S.Infinity: + return S.Infinity + I*pi/2 + if arg == -I*S.Infinity: + return S.Infinity - I*pi/2 + + if arg.is_zero: + return pi*I*S.Half + + if isinstance(arg, cosh) and arg.args[0].is_number: + z = arg.args[0] + if z.is_real: + return Abs(z) + r, i = match_real_imag(z) + if r is not None and i is not None: + f = floor(i/pi) + m = z - I*pi*f + even = f.is_even + if even is True: + if r.is_nonnegative: + return m + elif r.is_negative: + return -m + elif even is False: + m -= I*pi + if r.is_nonpositive: + return -m + elif r.is_positive: + return m + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return I*pi/2 + elif n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) >= 2 and n > 2: + p = previous_terms[-2] + return p * (n - 2)**2/(n*(n - 1)) * x**2 + else: + k = (n - 1) // 2 + R = RisingFactorial(S.Half, k) + F = factorial(k) + return -R / F * I * x**n / n + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + # Handling branch points + if x0 in (-S.One, S.Zero, S.One, S.ComplexInfinity): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + + if x0 is S.NaN: + expr = self.func(arg.as_leading_term(x)) + if expr.is_finite: + return expr + else: + return self + + # Handling points lying on branch cuts (-oo, 1) + if (x0 - 1).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if (x0 + 1).is_negative: + return self.func(x0) - 2*I*pi + return -self.func(x0) + elif not im(ndir).is_positive: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # acosh + arg = self.args[0] + arg0 = arg.subs(x, 0) + + # Handling branch points + if arg0 in (S.One, S.NegativeOne): + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + + # Handling points lying on branch cuts (-oo, 1) + if (arg0 - 1).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if (arg0 + 1).is_negative: + return res - 2*I*pi + return -res + elif not im(ndir).is_positive: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_rewrite_as_log(self, x, **kwargs): + return log(x + sqrt(x + 1) * sqrt(x - 1)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_acos(self, x, **kwargs): + return sqrt(x - 1)/sqrt(1 - x) * acos(x) + + def _eval_rewrite_as_asin(self, x, **kwargs): + return sqrt(x - 1)/sqrt(1 - x) * (pi/2 - asin(x)) + + def _eval_rewrite_as_asinh(self, x, **kwargs): + return sqrt(x - 1)/sqrt(1 - x) * (pi/2 + I*asinh(I*x, evaluate=False)) + + def _eval_rewrite_as_atanh(self, x, **kwargs): + sxm1 = sqrt(x - 1) + s1mx = sqrt(1 - x) + sx2m1 = sqrt(x**2 - 1) + return (pi/2*sxm1/s1mx*(1 - x * sqrt(1/x**2)) + + sxm1*sqrt(x + 1)/sx2m1 * atanh(sx2m1/x)) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return cosh + + def _eval_is_zero(self): + if (self.args[0] - 1).is_zero: + return True + + def _eval_is_extended_real(self): + return fuzzy_and([self.args[0].is_extended_real, (self.args[0] - 1).is_extended_nonnegative]) + + def _eval_is_finite(self): + return self.args[0].is_finite + + +class atanh(InverseHyperbolicFunction): + """ + ``atanh(x)`` is the inverse hyperbolic tangent of ``x``. + + The inverse hyperbolic tangent function. + + Examples + ======== + + >>> from sympy import atanh + >>> from sympy.abc import x + >>> atanh(x).diff(x) + 1/(1 - x**2) + + See Also + ======== + + asinh, acosh, tanh + """ + + def fdiff(self, argindex=1): + if argindex == 1: + return 1/(1 - self.args[0]**2) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg.is_zero: + return S.Zero + elif arg is S.One: + return S.Infinity + elif arg is S.NegativeOne: + return S.NegativeInfinity + elif arg is S.Infinity: + return -I * atan(arg) + elif arg is S.NegativeInfinity: + return I * atan(-arg) + elif arg.is_negative: + return -cls(-arg) + else: + if arg is S.ComplexInfinity: + from sympy.calculus.accumulationbounds import AccumBounds + return I*AccumBounds(-pi/2, pi/2) + + i_coeff = _imaginary_unit_as_coefficient(arg) + + if i_coeff is not None: + return I * atan(i_coeff) + else: + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if arg.is_zero: + return S.Zero + + if isinstance(arg, tanh) and arg.args[0].is_number: + z = arg.args[0] + if z.is_real: + return z + r, i = match_real_imag(z) + if r is not None and i is not None: + f = floor(2*i/pi) + even = f.is_even + m = z - I*f*pi/2 + if even is True: + return m + elif even is False: + return m - I*pi/2 + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + return x**n / n + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + if x0.is_zero: + return arg.as_leading_term(x) + if x0 is S.NaN: + expr = self.func(arg.as_leading_term(x)) + if expr.is_finite: + return expr + else: + return self + + # Handling branch points + if x0 in (-S.One, S.One, S.ComplexInfinity): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + # Handling points lying on branch cuts (-oo, -1] U [1, oo) + if (1 - x0**2).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if x0.is_negative: + return self.func(x0) - I*pi + elif im(ndir).is_positive: + if x0.is_positive: + return self.func(x0) + I*pi + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # atanh + arg = self.args[0] + arg0 = arg.subs(x, 0) + + # Handling branch points + if arg0 in (S.One, S.NegativeOne): + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + + # Handling points lying on branch cuts (-oo, -1] U [1, oo) + if (1 - arg0**2).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if arg0.is_negative: + return res - I*pi + elif im(ndir).is_positive: + if arg0.is_positive: + return res + I*pi + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_rewrite_as_log(self, x, **kwargs): + return (log(1 + x) - log(1 - x)) / 2 + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_asinh(self, x, **kwargs): + f = sqrt(1/(x**2 - 1)) + return (pi*x/(2*sqrt(-x**2)) - + sqrt(-x)*sqrt(1 - x**2)/sqrt(x)*f*asinh(f)) + + def _eval_is_zero(self): + if self.args[0].is_zero: + return True + + def _eval_is_extended_real(self): + return fuzzy_and([self.args[0].is_extended_real, (1 - self.args[0]).is_nonnegative, (self.args[0] + 1).is_nonnegative]) + + def _eval_is_finite(self): + return fuzzy_not(fuzzy_or([(self.args[0] - 1).is_zero, (self.args[0] + 1).is_zero])) + + def _eval_is_imaginary(self): + return self.args[0].is_imaginary + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return tanh + + +class acoth(InverseHyperbolicFunction): + """ + ``acoth(x)`` is the inverse hyperbolic cotangent of ``x``. + + The inverse hyperbolic cotangent function. + + Examples + ======== + + >>> from sympy import acoth + >>> from sympy.abc import x + >>> acoth(x).diff(x) + 1/(1 - x**2) + + See Also + ======== + + asinh, acosh, coth + """ + + def fdiff(self, argindex=1): + if argindex == 1: + return 1/(1 - self.args[0]**2) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Zero + elif arg is S.NegativeInfinity: + return S.Zero + elif arg.is_zero: + return pi*I / 2 + elif arg is S.One: + return S.Infinity + elif arg is S.NegativeOne: + return S.NegativeInfinity + elif arg.is_negative: + return -cls(-arg) + else: + if arg is S.ComplexInfinity: + return S.Zero + + i_coeff = _imaginary_unit_as_coefficient(arg) + + if i_coeff is not None: + return -I * acot(i_coeff) + else: + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if arg.is_zero: + return pi*I*S.Half + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return -I*pi/2 + elif n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + return x**n / n + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + if x0 is S.ComplexInfinity: + return (1/arg).as_leading_term(x) + if x0 is S.NaN: + expr = self.func(arg.as_leading_term(x)) + if expr.is_finite: + return expr + else: + return self + + # Handling branch points + if x0 in (-S.One, S.One, S.Zero): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + # Handling points lying on branch cuts [-1, 1] + if x0.is_real and (1 - x0**2).is_positive: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if x0.is_positive: + return self.func(x0) + I*pi + elif im(ndir).is_positive: + if x0.is_negative: + return self.func(x0) - I*pi + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # acoth + arg = self.args[0] + arg0 = arg.subs(x, 0) + + # Handling branch points + if arg0 in (S.One, S.NegativeOne): + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + + # Handling points lying on branch cuts [-1, 1] + if arg0.is_real and (1 - arg0**2).is_positive: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if arg0.is_positive: + return res + I*pi + elif im(ndir).is_positive: + if arg0.is_negative: + return res - I*pi + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_rewrite_as_log(self, x, **kwargs): + return (log(1 + 1/x) - log(1 - 1/x)) / 2 + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_atanh(self, x, **kwargs): + return atanh(1/x) + + def _eval_rewrite_as_asinh(self, x, **kwargs): + return (pi*I/2*(sqrt((x - 1)/x)*sqrt(x/(x - 1)) - sqrt(1 + 1/x)*sqrt(x/(x + 1))) + + x*sqrt(1/x**2)*asinh(sqrt(1/(x**2 - 1)))) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return coth + + def _eval_is_extended_real(self): + return fuzzy_and([self.args[0].is_extended_real, fuzzy_or([(self.args[0] - 1).is_extended_nonnegative, (self.args[0] + 1).is_extended_nonpositive])]) + + def _eval_is_finite(self): + return fuzzy_not(fuzzy_or([(self.args[0] - 1).is_zero, (self.args[0] + 1).is_zero])) + + +class asech(InverseHyperbolicFunction): + """ + ``asech(x)`` is the inverse hyperbolic secant of ``x``. + + The inverse hyperbolic secant function. + + Examples + ======== + + >>> from sympy import asech, sqrt, S + >>> from sympy.abc import x + >>> asech(x).diff(x) + -1/(x*sqrt(1 - x**2)) + >>> asech(1).diff(x) + 0 + >>> asech(1) + 0 + >>> asech(S(2)) + I*pi/3 + >>> asech(-sqrt(2)) + 3*I*pi/4 + >>> asech((sqrt(6) - sqrt(2))) + I*pi/12 + + See Also + ======== + + asinh, atanh, cosh, acoth + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Hyperbolic_function + .. [2] https://dlmf.nist.gov/4.37 + .. [3] https://functions.wolfram.com/ElementaryFunctions/ArcSech/ + + """ + + def fdiff(self, argindex=1): + if argindex == 1: + z = self.args[0] + return -1/(z*sqrt(1 - z**2)) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return pi*I / 2 + elif arg is S.NegativeInfinity: + return pi*I / 2 + elif arg.is_zero: + return S.Infinity + elif arg is S.One: + return S.Zero + elif arg is S.NegativeOne: + return pi*I + + if arg.is_number: + cst_table = _asech_table() + + if arg in cst_table: + if arg.is_extended_real: + return cst_table[arg]*I + return cst_table[arg] + + if arg is S.ComplexInfinity: + from sympy.calculus.accumulationbounds import AccumBounds + return I*AccumBounds(-pi/2, pi/2) + + if arg.is_zero: + return S.Infinity + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return log(2 / x) + elif n < 0 or n % 2 == 1: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) > 2 and n > 2: + p = previous_terms[-2] + return p * ((n - 1)*(n-2)) * x**2/(4 * (n//2)**2) + else: + k = n // 2 + R = RisingFactorial(S.Half, k) * n + F = factorial(k) * n // 2 * n // 2 + return -1 * R / F * x**n / 4 + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + # Handling branch points + if x0 in (-S.One, S.Zero, S.One, S.ComplexInfinity): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + + if x0 is S.NaN: + expr = self.func(arg.as_leading_term(x)) + if expr.is_finite: + return expr + else: + return self + + # Handling points lying on branch cuts (-oo, 0] U (1, oo) + if x0.is_negative or (1 - x0).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_positive: + if x0.is_positive or (x0 + 1).is_negative: + return -self.func(x0) + return self.func(x0) - 2*I*pi + elif not im(ndir).is_negative: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # asech + from sympy.series.order import O + arg = self.args[0] + arg0 = arg.subs(x, 0) + + # Handling branch points + if arg0 is S.One: + t = Dummy('t', positive=True) + ser = asech(S.One - t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.One - self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + if not g.is_meromorphic(x, 0): # cannot be expanded + return O(1) if n == 0 else O(sqrt(x)) + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + if arg0 is S.NegativeOne: + t = Dummy('t', positive=True) + ser = asech(S.NegativeOne + t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.One + self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + if not g.is_meromorphic(x, 0): # cannot be expanded + return O(1) if n == 0 else I*pi + O(sqrt(x)) + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + + # Handling points lying on branch cuts (-oo, 0] U (1, oo) + if arg0.is_negative or (1 - arg0).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_positive: + if arg0.is_positive or (arg0 + 1).is_negative: + return -res + return res - 2*I*pi + elif not im(ndir).is_negative: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return sech + + def _eval_rewrite_as_log(self, arg, **kwargs): + return log(1/arg + sqrt(1/arg - 1) * sqrt(1/arg + 1)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_acosh(self, arg, **kwargs): + return acosh(1/arg) + + def _eval_rewrite_as_asinh(self, arg, **kwargs): + return sqrt(1/arg - 1)/sqrt(1 - 1/arg)*(I*asinh(I/arg, evaluate=False) + + pi*S.Half) + + def _eval_rewrite_as_atanh(self, x, **kwargs): + return (I*pi*(1 - sqrt(x)*sqrt(1/x) - I/2*sqrt(-x)/sqrt(x) - I/2*sqrt(x**2)/sqrt(-x**2)) + + sqrt(1/(x + 1))*sqrt(x + 1)*atanh(sqrt(1 - x**2))) + + def _eval_rewrite_as_acsch(self, x, **kwargs): + return sqrt(1/x - 1)/sqrt(1 - 1/x)*(pi/2 - I*acsch(I*x, evaluate=False)) + + def _eval_is_extended_real(self): + return fuzzy_and([self.args[0].is_extended_real, self.args[0].is_nonnegative, (1 - self.args[0]).is_nonnegative]) + + def _eval_is_finite(self): + return fuzzy_not(self.args[0].is_zero) + + +class acsch(InverseHyperbolicFunction): + """ + ``acsch(x)`` is the inverse hyperbolic cosecant of ``x``. + + The inverse hyperbolic cosecant function. + + Examples + ======== + + >>> from sympy import acsch, sqrt, I + >>> from sympy.abc import x + >>> acsch(x).diff(x) + -1/(x**2*sqrt(1 + x**(-2))) + >>> acsch(1).diff(x) + 0 + >>> acsch(1) + log(1 + sqrt(2)) + >>> acsch(I) + -I*pi/2 + >>> acsch(-2*I) + I*pi/6 + >>> acsch(I*(sqrt(6) - sqrt(2))) + -5*I*pi/12 + + See Also + ======== + + asinh + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Hyperbolic_function + .. [2] https://dlmf.nist.gov/4.37 + .. [3] https://functions.wolfram.com/ElementaryFunctions/ArcCsch/ + + """ + + def fdiff(self, argindex=1): + if argindex == 1: + z = self.args[0] + return -1/(z**2*sqrt(1 + 1/z**2)) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Zero + elif arg is S.NegativeInfinity: + return S.Zero + elif arg.is_zero: + return S.ComplexInfinity + elif arg is S.One: + return log(1 + sqrt(2)) + elif arg is S.NegativeOne: + return - log(1 + sqrt(2)) + + if arg.is_number: + cst_table = _acsch_table() + + if arg in cst_table: + return cst_table[arg]*I + + if arg is S.ComplexInfinity: + return S.Zero + + if arg.is_infinite: + return S.Zero + + if arg.is_zero: + return S.ComplexInfinity + + if arg.could_extract_minus_sign(): + return -cls(-arg) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return log(2 / x) + elif n < 0 or n % 2 == 1: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) > 2 and n > 2: + p = previous_terms[-2] + return -p * ((n - 1)*(n-2)) * x**2/(4 * (n//2)**2) + else: + k = n // 2 + R = RisingFactorial(S.Half, k) * n + F = factorial(k) * n // 2 * n // 2 + return S.NegativeOne**(k +1) * R / F * x**n / 4 + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + # Handling branch points + if x0 in (-I, I, S.Zero): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + + if x0 is S.NaN: + expr = self.func(arg.as_leading_term(x)) + if expr.is_finite: + return expr + else: + return self + + if x0 is S.ComplexInfinity: + return (1/arg).as_leading_term(x) + # Handling points lying on branch cuts (-I, I) + if x0.is_imaginary and (1 + x0**2).is_positive: + ndir = arg.dir(x, cdir if cdir else 1) + if re(ndir).is_positive: + if im(x0).is_positive: + return -self.func(x0) - I*pi + elif re(ndir).is_negative: + if im(x0).is_negative: + return -self.func(x0) + I*pi + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # acsch + from sympy.series.order import O + arg = self.args[0] + arg0 = arg.subs(x, 0) + + # Handling branch points + if arg0 is I: + t = Dummy('t', positive=True) + ser = acsch(I + t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = -I + self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + if not g.is_meromorphic(x, 0): # cannot be expanded + return O(1) if n == 0 else -I*pi/2 + O(sqrt(x)) + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + res = ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + return res + + if arg0 == S.NegativeOne*I: + t = Dummy('t', positive=True) + ser = acsch(-I + t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = I + self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + if not g.is_meromorphic(x, 0): # cannot be expanded + return O(1) if n == 0 else I*pi/2 + O(sqrt(x)) + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + + # Handling points lying on branch cuts (-I, I) + if arg0.is_imaginary and (1 + arg0**2).is_positive: + ndir = self.args[0].dir(x, cdir if cdir else 1) + if re(ndir).is_positive: + if im(arg0).is_positive: + return -res - I*pi + elif re(ndir).is_negative: + if im(arg0).is_negative: + return -res + I*pi + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return csch + + def _eval_rewrite_as_log(self, arg, **kwargs): + return log(1/arg + sqrt(1/arg**2 + 1)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_asinh(self, arg, **kwargs): + return asinh(1/arg) + + def _eval_rewrite_as_acosh(self, arg, **kwargs): + return I*(sqrt(1 - I/arg)/sqrt(I/arg - 1)* + acosh(I/arg, evaluate=False) - pi*S.Half) + + def _eval_rewrite_as_atanh(self, arg, **kwargs): + arg2 = arg**2 + arg2p1 = arg2 + 1 + return sqrt(-arg2)/arg*(pi*S.Half - + sqrt(-arg2p1**2)/arg2p1*atanh(sqrt(arg2p1))) + + def _eval_is_zero(self): + return self.args[0].is_infinite + + def _eval_is_extended_real(self): + return self.args[0].is_extended_real + + def _eval_is_finite(self): + return fuzzy_not(self.args[0].is_zero) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/integers.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/integers.py new file mode 100644 index 0000000000000000000000000000000000000000..d0b58d32399144c39133855475d70c01b70b1a3f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/integers.py @@ -0,0 +1,710 @@ +from __future__ import annotations + +from sympy.core.basic import Basic +from sympy.core.expr import Expr + +from sympy.core import Add, S +from sympy.core.evalf import get_integer_part, PrecisionExhausted +from sympy.core.function import DefinedFunction +from sympy.core.logic import fuzzy_or, fuzzy_and +from sympy.core.numbers import Integer, int_valued +from sympy.core.relational import Gt, Lt, Ge, Le, Relational, is_eq, is_le, is_lt +from sympy.core.sympify import _sympify +from sympy.functions.elementary.complexes import im, re +from sympy.multipledispatch import dispatch + +############################################################################### +######################### FLOOR and CEILING FUNCTIONS ######################### +############################################################################### + + +class RoundFunction(DefinedFunction): + """Abstract base class for rounding functions.""" + + args: tuple[Expr] + + @classmethod + def eval(cls, arg): + if (v := cls._eval_number(arg)) is not None: + return v + if (v := cls._eval_const_number(arg)) is not None: + return v + + if arg.is_integer or arg.is_finite is False: + return arg + if arg.is_imaginary or (S.ImaginaryUnit*arg).is_real: + i = im(arg) + if not i.has(S.ImaginaryUnit): + return cls(i)*S.ImaginaryUnit + return cls(arg, evaluate=False) + + # Integral, numerical, symbolic part + ipart = npart = spart = S.Zero + + # Extract integral (or complex integral) terms + intof = lambda x: int(x) if int_valued(x) else ( + x if x.is_integer else None) + for t in Add.make_args(arg): + if t.is_imaginary and (i := intof(im(t))) is not None: + ipart += i*S.ImaginaryUnit + elif (i := intof(t)) is not None: + ipart += i + elif t.is_number: + npart += t + else: + spart += t + + if not (npart or spart): + return ipart + + # Evaluate npart numerically if independent of spart + if npart and ( + not spart or + npart.is_real and (spart.is_imaginary or (S.ImaginaryUnit*spart).is_real) or + npart.is_imaginary and spart.is_real): + try: + r, i = get_integer_part( + npart, cls._dir, {}, return_ints=True) + ipart += Integer(r) + Integer(i)*S.ImaginaryUnit + npart = S.Zero + except (PrecisionExhausted, NotImplementedError): + pass + + spart += npart + if not spart: + return ipart + elif spart.is_imaginary or (S.ImaginaryUnit*spart).is_real: + return ipart + cls(im(spart), evaluate=False)*S.ImaginaryUnit + elif isinstance(spart, (floor, ceiling)): + return ipart + spart + else: + return ipart + cls(spart, evaluate=False) + + @classmethod + def _eval_number(cls, arg): + raise NotImplementedError() + + def _eval_is_finite(self): + return self.args[0].is_finite + + def _eval_is_real(self): + return self.args[0].is_real + + def _eval_is_integer(self): + return self.args[0].is_real + + +class floor(RoundFunction): + """ + Floor is a univariate function which returns the largest integer + value not greater than its argument. This implementation + generalizes floor to complex numbers by taking the floor of the + real and imaginary parts separately. + + Examples + ======== + + >>> from sympy import floor, E, I, S, Float, Rational + >>> floor(17) + 17 + >>> floor(Rational(23, 10)) + 2 + >>> floor(2*E) + 5 + >>> floor(-Float(0.567)) + -1 + >>> floor(-I/2) + -I + >>> floor(S(5)/2 + 5*I/2) + 2 + 2*I + + See Also + ======== + + sympy.functions.elementary.integers.ceiling + + References + ========== + + .. [1] "Concrete mathematics" by Graham, pp. 87 + .. [2] https://mathworld.wolfram.com/FloorFunction.html + + """ + _dir = -1 + + @classmethod + def _eval_number(cls, arg): + if arg.is_Number: + return arg.floor() + if any(isinstance(i, j) + for i in (arg, -arg) for j in (floor, ceiling)): + return arg + if arg.is_NumberSymbol: + return arg.approximation_interval(Integer)[0] + + @classmethod + def _eval_const_number(cls, arg): + if arg.is_real: + if arg.is_zero: + return S.Zero + if arg.is_positive: + num, den = arg.as_numer_denom() + s = den.is_negative + if s is None: + return None + if s: + num, den = -num, -den + # 0 <= num/den < 1 -> 0 + if is_lt(num, den): + return S.Zero + # 1 <= num/den < 2 -> 1 + if fuzzy_and([is_le(den, num), is_lt(num, 2*den)]): + return S.One + if arg.is_negative: + num, den = arg.as_numer_denom() + s = den.is_negative + if s is None: + return None + if s: + num, den = -num, -den + # -1 <= num/den < 0 -> -1 + if is_le(-den, num): + return S.NegativeOne + # -2 <= num/den < -1 -> -2 + if fuzzy_and([is_le(-2*den, num), is_lt(num, -den)]): + return Integer(-2) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.accumulationbounds import AccumBounds + arg = self.args[0] + arg0 = arg.subs(x, 0) + r = self.subs(x, 0) + if arg0 is S.NaN or isinstance(arg0, AccumBounds): + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + r = floor(arg0) + if arg0.is_finite: + if arg0 == r: + ndir = arg.dir(x, cdir=cdir if cdir != 0 else 1) + if ndir.is_negative: + return r - 1 + elif ndir.is_positive: + return r + else: + raise NotImplementedError("Not sure of sign of %s" % ndir) + else: + return r + return arg.as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_nseries(self, x, n, logx, cdir=0): + arg = self.args[0] + arg0 = arg.subs(x, 0) + r = self.subs(x, 0) + if arg0 is S.NaN: + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + r = floor(arg0) + if arg0.is_infinite: + from sympy.calculus.accumulationbounds import AccumBounds + from sympy.series.order import Order + s = arg._eval_nseries(x, n, logx, cdir) + o = Order(1, (x, 0)) if n <= 0 else AccumBounds(-1, 0) + return s + o + if arg0 == r: + ndir = arg.dir(x, cdir=cdir if cdir != 0 else 1) + if ndir.is_negative: + return r - 1 + elif ndir.is_positive: + return r + else: + raise NotImplementedError("Not sure of sign of %s" % ndir) + else: + return r + + def _eval_is_negative(self): + return self.args[0].is_negative + + def _eval_is_nonnegative(self): + return self.args[0].is_nonnegative + + def _eval_rewrite_as_ceiling(self, arg, **kwargs): + return -ceiling(-arg) + + def _eval_rewrite_as_frac(self, arg, **kwargs): + return arg - frac(arg) + + def __le__(self, other): + other = S(other) + if self.args[0].is_real: + if other.is_integer: + return self.args[0] < other + 1 + if other.is_number and other.is_real: + return self.args[0] < ceiling(other) + if self.args[0] == other and other.is_real: + return S.true + if other is S.Infinity and self.is_finite: + return S.true + + return Le(self, other, evaluate=False) + + def __ge__(self, other): + other = S(other) + if self.args[0].is_real: + if other.is_integer: + return self.args[0] >= other + if other.is_number and other.is_real: + return self.args[0] >= ceiling(other) + if self.args[0] == other and other.is_real and other.is_noninteger: + return S.false + if other is S.NegativeInfinity and self.is_finite: + return S.true + + return Ge(self, other, evaluate=False) + + def __gt__(self, other): + other = S(other) + if self.args[0].is_real: + if other.is_integer: + return self.args[0] >= other + 1 + if other.is_number and other.is_real: + return self.args[0] >= ceiling(other) + if self.args[0] == other and other.is_real: + return S.false + if other is S.NegativeInfinity and self.is_finite: + return S.true + + return Gt(self, other, evaluate=False) + + def __lt__(self, other): + other = S(other) + if self.args[0].is_real: + if other.is_integer: + return self.args[0] < other + if other.is_number and other.is_real: + return self.args[0] < ceiling(other) + if self.args[0] == other and other.is_real and other.is_noninteger: + return S.true + if other is S.Infinity and self.is_finite: + return S.true + + return Lt(self, other, evaluate=False) + + +@dispatch(floor, Expr) +def _eval_is_eq(lhs, rhs): # noqa:F811 + return is_eq(lhs.rewrite(ceiling), rhs) or \ + is_eq(lhs.rewrite(frac),rhs) + + +class ceiling(RoundFunction): + """ + Ceiling is a univariate function which returns the smallest integer + value not less than its argument. This implementation + generalizes ceiling to complex numbers by taking the ceiling of the + real and imaginary parts separately. + + Examples + ======== + + >>> from sympy import ceiling, E, I, S, Float, Rational + >>> ceiling(17) + 17 + >>> ceiling(Rational(23, 10)) + 3 + >>> ceiling(2*E) + 6 + >>> ceiling(-Float(0.567)) + 0 + >>> ceiling(I/2) + I + >>> ceiling(S(5)/2 + 5*I/2) + 3 + 3*I + + See Also + ======== + + sympy.functions.elementary.integers.floor + + References + ========== + + .. [1] "Concrete mathematics" by Graham, pp. 87 + .. [2] https://mathworld.wolfram.com/CeilingFunction.html + + """ + _dir = 1 + + @classmethod + def _eval_number(cls, arg): + if arg.is_Number: + return arg.ceiling() + if any(isinstance(i, j) + for i in (arg, -arg) for j in (floor, ceiling)): + return arg + if arg.is_NumberSymbol: + return arg.approximation_interval(Integer)[1] + + @classmethod + def _eval_const_number(cls, arg): + if arg.is_real: + if arg.is_zero: + return S.Zero + if arg.is_positive: + num, den = arg.as_numer_denom() + s = den.is_negative + if s is None: + return None + if s: + num, den = -num, -den + # 0 < num/den <= 1 -> 1 + if is_le(num, den): + return S.One + # 1 < num/den <= 2 -> 2 + if fuzzy_and([is_lt(den, num), is_le(num, 2*den)]): + return Integer(2) + if arg.is_negative: + num, den = arg.as_numer_denom() + s = den.is_negative + if s is None: + return None + if s: + num, den = -num, -den + # -1 < num/den <= 0 -> 0 + if is_lt(-den, num): + return S.Zero + # -2 < num/den <= -1 -> -1 + if fuzzy_and([is_lt(-2*den, num), is_le(num, -den)]): + return S.NegativeOne + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.accumulationbounds import AccumBounds + arg = self.args[0] + arg0 = arg.subs(x, 0) + r = self.subs(x, 0) + if arg0 is S.NaN or isinstance(arg0, AccumBounds): + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + r = ceiling(arg0) + if arg0.is_finite: + if arg0 == r: + ndir = arg.dir(x, cdir=cdir if cdir != 0 else 1) + if ndir.is_negative: + return r + elif ndir.is_positive: + return r + 1 + else: + raise NotImplementedError("Not sure of sign of %s" % ndir) + else: + return r + return arg.as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_nseries(self, x, n, logx, cdir=0): + arg = self.args[0] + arg0 = arg.subs(x, 0) + r = self.subs(x, 0) + if arg0 is S.NaN: + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + r = ceiling(arg0) + if arg0.is_infinite: + from sympy.calculus.accumulationbounds import AccumBounds + from sympy.series.order import Order + s = arg._eval_nseries(x, n, logx, cdir) + o = Order(1, (x, 0)) if n <= 0 else AccumBounds(0, 1) + return s + o + if arg0 == r: + ndir = arg.dir(x, cdir=cdir if cdir != 0 else 1) + if ndir.is_negative: + return r + elif ndir.is_positive: + return r + 1 + else: + raise NotImplementedError("Not sure of sign of %s" % ndir) + else: + return r + + def _eval_rewrite_as_floor(self, arg, **kwargs): + return -floor(-arg) + + def _eval_rewrite_as_frac(self, arg, **kwargs): + return arg + frac(-arg) + + def _eval_is_positive(self): + return self.args[0].is_positive + + def _eval_is_nonpositive(self): + return self.args[0].is_nonpositive + + def __lt__(self, other): + other = S(other) + if self.args[0].is_real: + if other.is_integer: + return self.args[0] <= other - 1 + if other.is_number and other.is_real: + return self.args[0] <= floor(other) + if self.args[0] == other and other.is_real: + return S.false + if other is S.Infinity and self.is_finite: + return S.true + + return Lt(self, other, evaluate=False) + + def __gt__(self, other): + other = S(other) + if self.args[0].is_real: + if other.is_integer: + return self.args[0] > other + if other.is_number and other.is_real: + return self.args[0] > floor(other) + if self.args[0] == other and other.is_real and other.is_noninteger: + return S.true + if other is S.NegativeInfinity and self.is_finite: + return S.true + + return Gt(self, other, evaluate=False) + + def __ge__(self, other): + other = S(other) + if self.args[0].is_real: + if other.is_integer: + return self.args[0] > other - 1 + if other.is_number and other.is_real: + return self.args[0] > floor(other) + if self.args[0] == other and other.is_real: + return S.true + if other is S.NegativeInfinity and self.is_finite: + return S.true + + return Ge(self, other, evaluate=False) + + def __le__(self, other): + other = S(other) + if self.args[0].is_real: + if other.is_integer: + return self.args[0] <= other + if other.is_number and other.is_real: + return self.args[0] <= floor(other) + if self.args[0] == other and other.is_real and other.is_noninteger: + return S.false + if other is S.Infinity and self.is_finite: + return S.true + + return Le(self, other, evaluate=False) + + +@dispatch(ceiling, Basic) # type:ignore +def _eval_is_eq(lhs, rhs): # noqa:F811 + return is_eq(lhs.rewrite(floor), rhs) or is_eq(lhs.rewrite(frac),rhs) + + +class frac(DefinedFunction): + r"""Represents the fractional part of x + + For real numbers it is defined [1]_ as + + .. math:: + x - \left\lfloor{x}\right\rfloor + + Examples + ======== + + >>> from sympy import Symbol, frac, Rational, floor, I + >>> frac(Rational(4, 3)) + 1/3 + >>> frac(-Rational(4, 3)) + 2/3 + + returns zero for integer arguments + + >>> n = Symbol('n', integer=True) + >>> frac(n) + 0 + + rewrite as floor + + >>> x = Symbol('x') + >>> frac(x).rewrite(floor) + x - floor(x) + + for complex arguments + + >>> r = Symbol('r', real=True) + >>> t = Symbol('t', real=True) + >>> frac(t + I*r) + I*frac(r) + frac(t) + + See Also + ======== + + sympy.functions.elementary.integers.floor + sympy.functions.elementary.integers.ceiling + + References + =========== + + .. [1] https://en.wikipedia.org/wiki/Fractional_part + .. [2] https://mathworld.wolfram.com/FractionalPart.html + + """ + @classmethod + def eval(cls, arg): + from sympy.calculus.accumulationbounds import AccumBounds + + def _eval(arg): + if arg in (S.Infinity, S.NegativeInfinity): + return AccumBounds(0, 1) + if arg.is_integer: + return S.Zero + if arg.is_number: + if arg is S.NaN: + return S.NaN + elif arg is S.ComplexInfinity: + return S.NaN + else: + return arg - floor(arg) + return cls(arg, evaluate=False) + + real, imag = S.Zero, S.Zero + for t in Add.make_args(arg): + # Two checks are needed for complex arguments + # see issue-7649 for details + if t.is_imaginary or (S.ImaginaryUnit*t).is_real: + i = im(t) + if not i.has(S.ImaginaryUnit): + imag += i + else: + real += t + else: + real += t + + real = _eval(real) + imag = _eval(imag) + return real + S.ImaginaryUnit*imag + + def _eval_rewrite_as_floor(self, arg, **kwargs): + return arg - floor(arg) + + def _eval_rewrite_as_ceiling(self, arg, **kwargs): + return arg + ceiling(-arg) + + def _eval_is_finite(self): + return True + + def _eval_is_real(self): + return self.args[0].is_extended_real + + def _eval_is_imaginary(self): + return self.args[0].is_imaginary + + def _eval_is_integer(self): + return self.args[0].is_integer + + def _eval_is_zero(self): + return fuzzy_or([self.args[0].is_zero, self.args[0].is_integer]) + + def _eval_is_negative(self): + return False + + def __ge__(self, other): + if self.is_extended_real: + other = _sympify(other) + # Check if other <= 0 + if other.is_extended_nonpositive: + return S.true + # Check if other >= 1 + res = self._value_one_or_more(other) + if res is not None: + return not(res) + return Ge(self, other, evaluate=False) + + def __gt__(self, other): + if self.is_extended_real: + other = _sympify(other) + # Check if other < 0 + res = self._value_one_or_more(other) + if res is not None: + return not(res) + # Check if other >= 1 + if other.is_extended_negative: + return S.true + return Gt(self, other, evaluate=False) + + def __le__(self, other): + if self.is_extended_real: + other = _sympify(other) + # Check if other < 0 + if other.is_extended_negative: + return S.false + # Check if other >= 1 + res = self._value_one_or_more(other) + if res is not None: + return res + return Le(self, other, evaluate=False) + + def __lt__(self, other): + if self.is_extended_real: + other = _sympify(other) + # Check if other <= 0 + if other.is_extended_nonpositive: + return S.false + # Check if other >= 1 + res = self._value_one_or_more(other) + if res is not None: + return res + return Lt(self, other, evaluate=False) + + def _value_one_or_more(self, other): + if other.is_extended_real: + if other.is_number: + res = other >= 1 + if res and not isinstance(res, Relational): + return S.true + if other.is_integer and other.is_positive: + return S.true + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.accumulationbounds import AccumBounds + arg = self.args[0] + arg0 = arg.subs(x, 0) + r = self.subs(x, 0) + + if arg0.is_finite: + if r.is_zero: + ndir = arg.dir(x, cdir=cdir) + if ndir.is_negative: + return S.One + return (arg - arg0).as_leading_term(x, logx=logx, cdir=cdir) + else: + return r + elif arg0 in (S.ComplexInfinity, S.Infinity, S.NegativeInfinity): + return AccumBounds(0, 1) + return arg.as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_nseries(self, x, n, logx, cdir=0): + from sympy.series.order import Order + arg = self.args[0] + arg0 = arg.subs(x, 0) + r = self.subs(x, 0) + + if arg0.is_infinite: + from sympy.calculus.accumulationbounds import AccumBounds + o = Order(1, (x, 0)) if n <= 0 else AccumBounds(0, 1) + Order(x**n, (x, 0)) + return o + else: + res = (arg - arg0)._eval_nseries(x, n, logx=logx, cdir=cdir) + if r.is_zero: + ndir = arg.dir(x, cdir=cdir) + res += S.One if ndir.is_negative else S.Zero + else: + res += r + return res + + +@dispatch(frac, Basic) # type:ignore +def _eval_is_eq(lhs, rhs): # noqa:F811 + if (lhs.rewrite(floor) == rhs) or \ + (lhs.rewrite(ceiling) == rhs): + return True + # Check if other < 0 + if rhs.is_extended_negative: + return False + # Check if other >= 1 + res = lhs._value_one_or_more(rhs) + if res is not None: + return False diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/miscellaneous.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/miscellaneous.py new file mode 100644 index 0000000000000000000000000000000000000000..c7f3016bc7ea0d5c4ad778cf9922c941acb7fc44 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/miscellaneous.py @@ -0,0 +1,915 @@ +from sympy.core import S, sympify, NumberKind +from sympy.utilities.iterables import sift +from sympy.core.add import Add +from sympy.core.containers import Tuple +from sympy.core.operations import LatticeOp, ShortCircuit +from sympy.core.function import (Application, Lambda, + ArgumentIndexError, DefinedFunction) +from sympy.core.expr import Expr +from sympy.core.exprtools import factor_terms +from sympy.core.mod import Mod +from sympy.core.mul import Mul +from sympy.core.numbers import Rational +from sympy.core.power import Pow +from sympy.core.relational import Eq, Relational +from sympy.core.singleton import Singleton +from sympy.core.sorting import ordered +from sympy.core.symbol import Dummy +from sympy.core.rules import Transform +from sympy.core.logic import fuzzy_and, fuzzy_or, _torf +from sympy.core.traversal import walk +from sympy.core.numbers import Integer +from sympy.logic.boolalg import And, Or + + +def _minmax_as_Piecewise(op, *args): + # helper for Min/Max rewrite as Piecewise + from sympy.functions.elementary.piecewise import Piecewise + ec = [] + for i, a in enumerate(args): + c = [Relational(a, args[j], op) for j in range(i + 1, len(args))] + ec.append((a, And(*c))) + return Piecewise(*ec) + + +class IdentityFunction(Lambda, metaclass=Singleton): + """ + The identity function + + Examples + ======== + + >>> from sympy import Id, Symbol + >>> x = Symbol('x') + >>> Id(x) + x + + """ + + _symbol = Dummy('x') + + @property + def signature(self): + return Tuple(self._symbol) + + @property + def expr(self): + return self._symbol + + +Id = S.IdentityFunction + +############################################################################### +############################# ROOT and SQUARE ROOT FUNCTION ################### +############################################################################### + + +def sqrt(arg, evaluate=None): + """Returns the principal square root. + + Parameters + ========== + + evaluate : bool, optional + The parameter determines if the expression should be evaluated. + If ``None``, its value is taken from + ``global_parameters.evaluate``. + + Examples + ======== + + >>> from sympy import sqrt, Symbol, S + >>> x = Symbol('x') + + >>> sqrt(x) + sqrt(x) + + >>> sqrt(x)**2 + x + + Note that sqrt(x**2) does not simplify to x. + + >>> sqrt(x**2) + sqrt(x**2) + + This is because the two are not equal to each other in general. + For example, consider x == -1: + + >>> from sympy import Eq + >>> Eq(sqrt(x**2), x).subs(x, -1) + False + + This is because sqrt computes the principal square root, so the square may + put the argument in a different branch. This identity does hold if x is + positive: + + >>> y = Symbol('y', positive=True) + >>> sqrt(y**2) + y + + You can force this simplification by using the powdenest() function with + the force option set to True: + + >>> from sympy import powdenest + >>> sqrt(x**2) + sqrt(x**2) + >>> powdenest(sqrt(x**2), force=True) + x + + To get both branches of the square root you can use the rootof function: + + >>> from sympy import rootof + + >>> [rootof(x**2-3,i) for i in (0,1)] + [-sqrt(3), sqrt(3)] + + Although ``sqrt`` is printed, there is no ``sqrt`` function so looking for + ``sqrt`` in an expression will fail: + + >>> from sympy.utilities.misc import func_name + >>> func_name(sqrt(x)) + 'Pow' + >>> sqrt(x).has(sqrt) + False + + To find ``sqrt`` look for ``Pow`` with an exponent of ``1/2``: + + >>> (x + 1/sqrt(x)).find(lambda i: i.is_Pow and abs(i.exp) is S.Half) + {1/sqrt(x)} + + See Also + ======== + + sympy.polys.rootoftools.rootof, root, real_root + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Square_root + .. [2] https://en.wikipedia.org/wiki/Principal_value + """ + # arg = sympify(arg) is handled by Pow + return Pow(arg, S.Half, evaluate=evaluate) + + +def cbrt(arg, evaluate=None): + """Returns the principal cube root. + + Parameters + ========== + + evaluate : bool, optional + The parameter determines if the expression should be evaluated. + If ``None``, its value is taken from + ``global_parameters.evaluate``. + + Examples + ======== + + >>> from sympy import cbrt, Symbol + >>> x = Symbol('x') + + >>> cbrt(x) + x**(1/3) + + >>> cbrt(x)**3 + x + + Note that cbrt(x**3) does not simplify to x. + + >>> cbrt(x**3) + (x**3)**(1/3) + + This is because the two are not equal to each other in general. + For example, consider `x == -1`: + + >>> from sympy import Eq + >>> Eq(cbrt(x**3), x).subs(x, -1) + False + + This is because cbrt computes the principal cube root, this + identity does hold if `x` is positive: + + >>> y = Symbol('y', positive=True) + >>> cbrt(y**3) + y + + See Also + ======== + + sympy.polys.rootoftools.rootof, root, real_root + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Cube_root + .. [2] https://en.wikipedia.org/wiki/Principal_value + + """ + return Pow(arg, Rational(1, 3), evaluate=evaluate) + + +def root(arg, n, k=0, evaluate=None): + r"""Returns the *k*-th *n*-th root of ``arg``. + + Parameters + ========== + + k : int, optional + Should be an integer in $\{0, 1, ..., n-1\}$. + Defaults to the principal root if $0$. + + evaluate : bool, optional + The parameter determines if the expression should be evaluated. + If ``None``, its value is taken from + ``global_parameters.evaluate``. + + Examples + ======== + + >>> from sympy import root, Rational + >>> from sympy.abc import x, n + + >>> root(x, 2) + sqrt(x) + + >>> root(x, 3) + x**(1/3) + + >>> root(x, n) + x**(1/n) + + >>> root(x, -Rational(2, 3)) + x**(-3/2) + + To get the k-th n-th root, specify k: + + >>> root(-2, 3, 2) + -(-1)**(2/3)*2**(1/3) + + To get all n n-th roots you can use the rootof function. + The following examples show the roots of unity for n + equal 2, 3 and 4: + + >>> from sympy import rootof + + >>> [rootof(x**2 - 1, i) for i in range(2)] + [-1, 1] + + >>> [rootof(x**3 - 1,i) for i in range(3)] + [1, -1/2 - sqrt(3)*I/2, -1/2 + sqrt(3)*I/2] + + >>> [rootof(x**4 - 1,i) for i in range(4)] + [-1, 1, -I, I] + + SymPy, like other symbolic algebra systems, returns the + complex root of negative numbers. This is the principal + root and differs from the text-book result that one might + be expecting. For example, the cube root of -8 does not + come back as -2: + + >>> root(-8, 3) + 2*(-1)**(1/3) + + The real_root function can be used to either make the principal + result real (or simply to return the real root directly): + + >>> from sympy import real_root + >>> real_root(_) + -2 + >>> real_root(-32, 5) + -2 + + Alternatively, the n//2-th n-th root of a negative number can be + computed with root: + + >>> root(-32, 5, 5//2) + -2 + + See Also + ======== + + sympy.polys.rootoftools.rootof + sympy.core.intfunc.integer_nthroot + sqrt, real_root + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Square_root + .. [2] https://en.wikipedia.org/wiki/Real_root + .. [3] https://en.wikipedia.org/wiki/Root_of_unity + .. [4] https://en.wikipedia.org/wiki/Principal_value + .. [5] https://mathworld.wolfram.com/CubeRoot.html + + """ + n = sympify(n) + if k: + return Mul(Pow(arg, S.One/n, evaluate=evaluate), S.NegativeOne**(2*k/n), evaluate=evaluate) + return Pow(arg, 1/n, evaluate=evaluate) + + +def real_root(arg, n=None, evaluate=None): + r"""Return the real *n*'th-root of *arg* if possible. + + Parameters + ========== + + n : int or None, optional + If *n* is ``None``, then all instances of + $(-n)^{1/\text{odd}}$ will be changed to $-n^{1/\text{odd}}$. + This will only create a real root of a principal root. + The presence of other factors may cause the result to not be + real. + + evaluate : bool, optional + The parameter determines if the expression should be evaluated. + If ``None``, its value is taken from + ``global_parameters.evaluate``. + + Examples + ======== + + >>> from sympy import root, real_root + + >>> real_root(-8, 3) + -2 + >>> root(-8, 3) + 2*(-1)**(1/3) + >>> real_root(_) + -2 + + If one creates a non-principal root and applies real_root, the + result will not be real (so use with caution): + + >>> root(-8, 3, 2) + -2*(-1)**(2/3) + >>> real_root(_) + -2*(-1)**(2/3) + + See Also + ======== + + sympy.polys.rootoftools.rootof + sympy.core.intfunc.integer_nthroot + root, sqrt + """ + from sympy.functions.elementary.complexes import Abs, im, sign + from sympy.functions.elementary.piecewise import Piecewise + if n is not None: + return Piecewise( + (root(arg, n, evaluate=evaluate), Or(Eq(n, S.One), Eq(n, S.NegativeOne))), + (Mul(sign(arg), root(Abs(arg), n, evaluate=evaluate), evaluate=evaluate), + And(Eq(im(arg), S.Zero), Eq(Mod(n, 2), S.One))), + (root(arg, n, evaluate=evaluate), True)) + rv = sympify(arg) + n1pow = Transform(lambda x: -(-x.base)**x.exp, + lambda x: + x.is_Pow and + x.base.is_negative and + x.exp.is_Rational and + x.exp.p == 1 and x.exp.q % 2) + return rv.xreplace(n1pow) + +############################################################################### +############################# MINIMUM and MAXIMUM ############################# +############################################################################### + + +class MinMaxBase(Expr, LatticeOp): + def __new__(cls, *args, **assumptions): + from sympy.core.parameters import global_parameters + evaluate = assumptions.pop('evaluate', global_parameters.evaluate) + args = (sympify(arg) for arg in args) + + # first standard filter, for cls.zero and cls.identity + # also reshape Max(a, Max(b, c)) to Max(a, b, c) + + if evaluate: + try: + args = frozenset(cls._new_args_filter(args)) + except ShortCircuit: + return cls.zero + # remove redundant args that are easily identified + args = cls._collapse_arguments(args, **assumptions) + # find local zeros + args = cls._find_localzeros(args, **assumptions) + args = frozenset(args) + + if not args: + return cls.identity + + if len(args) == 1: + return list(args).pop() + + # base creation + obj = Expr.__new__(cls, *ordered(args), **assumptions) + obj._argset = args + return obj + + @classmethod + def _collapse_arguments(cls, args, **assumptions): + """Remove redundant args. + + Examples + ======== + + >>> from sympy import Min, Max + >>> from sympy.abc import a, b, c, d, e + + Any arg in parent that appears in any + parent-like function in any of the flat args + of parent can be removed from that sub-arg: + + >>> Min(a, Max(b, Min(a, c, d))) + Min(a, Max(b, Min(c, d))) + + If the arg of parent appears in an opposite-than parent + function in any of the flat args of parent that function + can be replaced with the arg: + + >>> Min(a, Max(b, Min(c, d, Max(a, e)))) + Min(a, Max(b, Min(a, c, d))) + """ + if not args: + return args + args = list(ordered(args)) + if cls == Min: + other = Max + else: + other = Min + + # find global comparable max of Max and min of Min if a new + # value is being introduced in these args at position 0 of + # the ordered args + if args[0].is_number: + sifted = mins, maxs = [], [] + for i in args: + for v in walk(i, Min, Max): + if v.args[0].is_comparable: + sifted[isinstance(v, Max)].append(v) + small = Min.identity + for i in mins: + v = i.args[0] + if v.is_number and (v < small) == True: + small = v + big = Max.identity + for i in maxs: + v = i.args[0] + if v.is_number and (v > big) == True: + big = v + # at the point when this function is called from __new__, + # there may be more than one numeric arg present since + # local zeros have not been handled yet, so look through + # more than the first arg + if cls == Min: + for arg in args: + if not arg.is_number: + break + if (arg < small) == True: + small = arg + elif cls == Max: + for arg in args: + if not arg.is_number: + break + if (arg > big) == True: + big = arg + T = None + if cls == Min: + if small != Min.identity: + other = Max + T = small + elif big != Max.identity: + other = Min + T = big + if T is not None: + # remove numerical redundancy + for i in range(len(args)): + a = args[i] + if isinstance(a, other): + a0 = a.args[0] + if ((a0 > T) if other == Max else (a0 < T)) == True: + args[i] = cls.identity + + # remove redundant symbolic args + def do(ai, a): + if not isinstance(ai, (Min, Max)): + return ai + cond = a in ai.args + if not cond: + return ai.func(*[do(i, a) for i in ai.args], + evaluate=False) + if isinstance(ai, cls): + return ai.func(*[do(i, a) for i in ai.args if i != a], + evaluate=False) + return a + for i, a in enumerate(args): + args[i + 1:] = [do(ai, a) for ai in args[i + 1:]] + + # factor out common elements as for + # Min(Max(x, y), Max(x, z)) -> Max(x, Min(y, z)) + # and vice versa when swapping Min/Max -- do this only for the + # easy case where all functions contain something in common; + # trying to find some optimal subset of args to modify takes + # too long + + def factor_minmax(args): + is_other = lambda arg: isinstance(arg, other) + other_args, remaining_args = sift(args, is_other, binary=True) + if not other_args: + return args + + # Min(Max(x, y, z), Max(x, y, u, v)) -> {x,y}, ({z}, {u,v}) + arg_sets = [set(arg.args) for arg in other_args] + common = set.intersection(*arg_sets) + if not common: + return args + + new_other_args = list(common) + arg_sets_diff = [arg_set - common for arg_set in arg_sets] + + # If any set is empty after removing common then all can be + # discarded e.g. Min(Max(a, b, c), Max(a, b)) -> Max(a, b) + if all(arg_sets_diff): + other_args_diff = [other(*s, evaluate=False) for s in arg_sets_diff] + new_other_args.append(cls(*other_args_diff, evaluate=False)) + + other_args_factored = other(*new_other_args, evaluate=False) + return remaining_args + [other_args_factored] + + if len(args) > 1: + args = factor_minmax(args) + + return args + + @classmethod + def _new_args_filter(cls, arg_sequence): + """ + Generator filtering args. + + first standard filter, for cls.zero and cls.identity. + Also reshape ``Max(a, Max(b, c))`` to ``Max(a, b, c)``, + and check arguments for comparability + """ + for arg in arg_sequence: + # pre-filter, checking comparability of arguments + if not isinstance(arg, Expr) or arg.is_extended_real is False or ( + arg.is_number and + not arg.is_comparable): + raise ValueError("The argument '%s' is not comparable." % arg) + + if arg == cls.zero: + raise ShortCircuit(arg) + elif arg == cls.identity: + continue + elif arg.func == cls: + yield from arg.args + else: + yield arg + + @classmethod + def _find_localzeros(cls, values, **options): + """ + Sequentially allocate values to localzeros. + + When a value is identified as being more extreme than another member it + replaces that member; if this is never true, then the value is simply + appended to the localzeros. + """ + localzeros = set() + for v in values: + is_newzero = True + localzeros_ = list(localzeros) + for z in localzeros_: + if id(v) == id(z): + is_newzero = False + else: + con = cls._is_connected(v, z) + if con: + is_newzero = False + if con is True or con == cls: + localzeros.remove(z) + localzeros.update([v]) + if is_newzero: + localzeros.update([v]) + return localzeros + + @classmethod + def _is_connected(cls, x, y): + """ + Check if x and y are connected somehow. + """ + for i in range(2): + if x == y: + return True + t, f = Max, Min + for op in "><": + for j in range(2): + try: + if op == ">": + v = x >= y + else: + v = x <= y + except TypeError: + return False # non-real arg + if not v.is_Relational: + return t if v else f + t, f = f, t + x, y = y, x + x, y = y, x # run next pass with reversed order relative to start + # simplification can be expensive, so be conservative + # in what is attempted + x = factor_terms(x - y) + y = S.Zero + + return False + + def _eval_derivative(self, s): + # f(x).diff(s) -> x.diff(s) * f.fdiff(1)(s) + i = 0 + l = [] + for a in self.args: + i += 1 + da = a.diff(s) + if da.is_zero: + continue + try: + df = self.fdiff(i) + except ArgumentIndexError: + df = super().fdiff(i) + l.append(df * da) + return Add(*l) + + def _eval_rewrite_as_Abs(self, *args, **kwargs): + from sympy.functions.elementary.complexes import Abs + s = (args[0] + self.func(*args[1:]))/2 + d = abs(args[0] - self.func(*args[1:]))/2 + return (s + d if isinstance(self, Max) else s - d).rewrite(Abs) + + def evalf(self, n=15, **options): + return self.func(*[a.evalf(n, **options) for a in self.args]) + + def n(self, *args, **kwargs): + return self.evalf(*args, **kwargs) + + _eval_is_algebraic = lambda s: _torf(i.is_algebraic for i in s.args) + _eval_is_antihermitian = lambda s: _torf(i.is_antihermitian for i in s.args) + _eval_is_commutative = lambda s: _torf(i.is_commutative for i in s.args) + _eval_is_complex = lambda s: _torf(i.is_complex for i in s.args) + _eval_is_composite = lambda s: _torf(i.is_composite for i in s.args) + _eval_is_even = lambda s: _torf(i.is_even for i in s.args) + _eval_is_finite = lambda s: _torf(i.is_finite for i in s.args) + _eval_is_hermitian = lambda s: _torf(i.is_hermitian for i in s.args) + _eval_is_imaginary = lambda s: _torf(i.is_imaginary for i in s.args) + _eval_is_infinite = lambda s: _torf(i.is_infinite for i in s.args) + _eval_is_integer = lambda s: _torf(i.is_integer for i in s.args) + _eval_is_irrational = lambda s: _torf(i.is_irrational for i in s.args) + _eval_is_negative = lambda s: _torf(i.is_negative for i in s.args) + _eval_is_noninteger = lambda s: _torf(i.is_noninteger for i in s.args) + _eval_is_nonnegative = lambda s: _torf(i.is_nonnegative for i in s.args) + _eval_is_nonpositive = lambda s: _torf(i.is_nonpositive for i in s.args) + _eval_is_nonzero = lambda s: _torf(i.is_nonzero for i in s.args) + _eval_is_odd = lambda s: _torf(i.is_odd for i in s.args) + _eval_is_polar = lambda s: _torf(i.is_polar for i in s.args) + _eval_is_positive = lambda s: _torf(i.is_positive for i in s.args) + _eval_is_prime = lambda s: _torf(i.is_prime for i in s.args) + _eval_is_rational = lambda s: _torf(i.is_rational for i in s.args) + _eval_is_real = lambda s: _torf(i.is_real for i in s.args) + _eval_is_extended_real = lambda s: _torf(i.is_extended_real for i in s.args) + _eval_is_transcendental = lambda s: _torf(i.is_transcendental for i in s.args) + _eval_is_zero = lambda s: _torf(i.is_zero for i in s.args) + + +class Max(MinMaxBase, Application): + r""" + Return, if possible, the maximum value of the list. + + When number of arguments is equal one, then + return this argument. + + When number of arguments is equal two, then + return, if possible, the value from (a, b) that is $\ge$ the other. + + In common case, when the length of list greater than 2, the task + is more complicated. Return only the arguments, which are greater + than others, if it is possible to determine directional relation. + + If is not possible to determine such a relation, return a partially + evaluated result. + + Assumptions are used to make the decision too. + + Also, only comparable arguments are permitted. + + It is named ``Max`` and not ``max`` to avoid conflicts + with the built-in function ``max``. + + + Examples + ======== + + >>> from sympy import Max, Symbol, oo + >>> from sympy.abc import x, y, z + >>> p = Symbol('p', positive=True) + >>> n = Symbol('n', negative=True) + + >>> Max(x, -2) + Max(-2, x) + >>> Max(x, -2).subs(x, 3) + 3 + >>> Max(p, -2) + p + >>> Max(x, y) + Max(x, y) + >>> Max(x, y) == Max(y, x) + True + >>> Max(x, Max(y, z)) + Max(x, y, z) + >>> Max(n, 8, p, 7, -oo) + Max(8, p) + >>> Max (1, x, oo) + oo + + * Algorithm + + The task can be considered as searching of supremums in the + directed complete partial orders [1]_. + + The source values are sequentially allocated by the isolated subsets + in which supremums are searched and result as Max arguments. + + If the resulted supremum is single, then it is returned. + + The isolated subsets are the sets of values which are only the comparable + with each other in the current set. E.g. natural numbers are comparable with + each other, but not comparable with the `x` symbol. Another example: the + symbol `x` with negative assumption is comparable with a natural number. + + Also there are "least" elements, which are comparable with all others, + and have a zero property (maximum or minimum for all elements). + For example, in case of $\infty$, the allocation operation is terminated + and only this value is returned. + + Assumption: + - if $A > B > C$ then $A > C$ + - if $A = B$ then $B$ can be removed + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Directed_complete_partial_order + .. [2] https://en.wikipedia.org/wiki/Lattice_%28order%29 + + See Also + ======== + + Min : find minimum values + """ + zero = S.Infinity + identity = S.NegativeInfinity + + def fdiff( self, argindex ): + from sympy.functions.special.delta_functions import Heaviside + n = len(self.args) + if 0 < argindex and argindex <= n: + argindex -= 1 + if n == 2: + return Heaviside(self.args[argindex] - self.args[1 - argindex]) + newargs = tuple([self.args[i] for i in range(n) if i != argindex]) + return Heaviside(self.args[argindex] - Max(*newargs)) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Heaviside(self, *args, **kwargs): + from sympy.functions.special.delta_functions import Heaviside + return Add(*[j*Mul(*[Heaviside(j - i) for i in args if i!=j]) \ + for j in args]) + + def _eval_rewrite_as_Piecewise(self, *args, **kwargs): + return _minmax_as_Piecewise('>=', *args) + + def _eval_is_positive(self): + return fuzzy_or(a.is_positive for a in self.args) + + def _eval_is_nonnegative(self): + return fuzzy_or(a.is_nonnegative for a in self.args) + + def _eval_is_negative(self): + return fuzzy_and(a.is_negative for a in self.args) + + +class Min(MinMaxBase, Application): + """ + Return, if possible, the minimum value of the list. + It is named ``Min`` and not ``min`` to avoid conflicts + with the built-in function ``min``. + + Examples + ======== + + >>> from sympy import Min, Symbol, oo + >>> from sympy.abc import x, y + >>> p = Symbol('p', positive=True) + >>> n = Symbol('n', negative=True) + + >>> Min(x, -2) + Min(-2, x) + >>> Min(x, -2).subs(x, 3) + -2 + >>> Min(p, -3) + -3 + >>> Min(x, y) + Min(x, y) + >>> Min(n, 8, p, -7, p, oo) + Min(-7, n) + + See Also + ======== + + Max : find maximum values + """ + zero = S.NegativeInfinity + identity = S.Infinity + + def fdiff( self, argindex ): + from sympy.functions.special.delta_functions import Heaviside + n = len(self.args) + if 0 < argindex and argindex <= n: + argindex -= 1 + if n == 2: + return Heaviside( self.args[1-argindex] - self.args[argindex] ) + newargs = tuple([ self.args[i] for i in range(n) if i != argindex]) + return Heaviside( Min(*newargs) - self.args[argindex] ) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Heaviside(self, *args, **kwargs): + from sympy.functions.special.delta_functions import Heaviside + return Add(*[j*Mul(*[Heaviside(i-j) for i in args if i!=j]) \ + for j in args]) + + def _eval_rewrite_as_Piecewise(self, *args, **kwargs): + return _minmax_as_Piecewise('<=', *args) + + def _eval_is_positive(self): + return fuzzy_and(a.is_positive for a in self.args) + + def _eval_is_nonnegative(self): + return fuzzy_and(a.is_nonnegative for a in self.args) + + def _eval_is_negative(self): + return fuzzy_or(a.is_negative for a in self.args) + + +class Rem(DefinedFunction): + """Returns the remainder when ``p`` is divided by ``q`` where ``p`` is finite + and ``q`` is not equal to zero. The result, ``p - int(p/q)*q``, has the same sign + as the divisor. + + Parameters + ========== + + p : Expr + Dividend. + + q : Expr + Divisor. + + Notes + ===== + + ``Rem`` corresponds to the ``%`` operator in C. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy import Rem + >>> Rem(x**3, y) + Rem(x**3, y) + >>> Rem(x**3, y).subs({x: -5, y: 3}) + -2 + + See Also + ======== + + Mod + """ + kind = NumberKind + + @classmethod + def eval(cls, p, q): + """Return the function remainder if both p, q are numbers and q is not + zero. + """ + + if q.is_zero: + raise ZeroDivisionError("Division by zero") + if p is S.NaN or q is S.NaN or p.is_finite is False or q.is_finite is False: + return S.NaN + if p is S.Zero or p in (q, -q) or (p.is_integer and q == 1): + return S.Zero + + if q.is_Number: + if p.is_Number: + return p - Integer(p/q)*q diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/piecewise.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/piecewise.py new file mode 100644 index 0000000000000000000000000000000000000000..fe4a4d4f57e2c3af170dac994e11782b9ed54b8f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/piecewise.py @@ -0,0 +1,1517 @@ +from sympy.core import S, diff, Tuple, Dummy, Mul +from sympy.core.basic import Basic, as_Basic +from sympy.core.function import DefinedFunction +from sympy.core.numbers import Rational, NumberSymbol, _illegal +from sympy.core.parameters import global_parameters +from sympy.core.relational import (Lt, Gt, Eq, Ne, Relational, + _canonical, _canonical_coeff) +from sympy.core.sorting import ordered +from sympy.functions.elementary.miscellaneous import Max, Min +from sympy.logic.boolalg import (And, Boolean, distribute_and_over_or, Not, + true, false, Or, ITE, simplify_logic, to_cnf, distribute_or_over_and) +from sympy.utilities.iterables import uniq, sift, common_prefix +from sympy.utilities.misc import filldedent, func_name + +from itertools import product + +Undefined = S.NaN # Piecewise() + +class ExprCondPair(Tuple): + """Represents an expression, condition pair.""" + + def __new__(cls, expr, cond): + expr = as_Basic(expr) + if cond == True: + return Tuple.__new__(cls, expr, true) + elif cond == False: + return Tuple.__new__(cls, expr, false) + elif isinstance(cond, Basic) and cond.has(Piecewise): + cond = piecewise_fold(cond) + if isinstance(cond, Piecewise): + cond = cond.rewrite(ITE) + + if not isinstance(cond, Boolean): + raise TypeError(filldedent(''' + Second argument must be a Boolean, + not `%s`''' % func_name(cond))) + return Tuple.__new__(cls, expr, cond) + + @property + def expr(self): + """ + Returns the expression of this pair. + """ + return self.args[0] + + @property + def cond(self): + """ + Returns the condition of this pair. + """ + return self.args[1] + + @property + def is_commutative(self): + return self.expr.is_commutative + + def __iter__(self): + yield self.expr + yield self.cond + + def _eval_simplify(self, **kwargs): + return self.func(*[a.simplify(**kwargs) for a in self.args]) + + +class Piecewise(DefinedFunction): + """ + Represents a piecewise function. + + Usage: + + Piecewise( (expr,cond), (expr,cond), ... ) + - Each argument is a 2-tuple defining an expression and condition + - The conds are evaluated in turn returning the first that is True. + If any of the evaluated conds are not explicitly False, + e.g. ``x < 1``, the function is returned in symbolic form. + - If the function is evaluated at a place where all conditions are False, + nan will be returned. + - Pairs where the cond is explicitly False, will be removed and no pair + appearing after a True condition will ever be retained. If a single + pair with a True condition remains, it will be returned, even when + evaluation is False. + + Examples + ======== + + >>> from sympy import Piecewise, log, piecewise_fold + >>> from sympy.abc import x, y + >>> f = x**2 + >>> g = log(x) + >>> p = Piecewise((0, x < -1), (f, x <= 1), (g, True)) + >>> p.subs(x,1) + 1 + >>> p.subs(x,5) + log(5) + + Booleans can contain Piecewise elements: + + >>> cond = (x < y).subs(x, Piecewise((2, x < 0), (3, True))); cond + Piecewise((2, x < 0), (3, True)) < y + + The folded version of this results in a Piecewise whose + expressions are Booleans: + + >>> folded_cond = piecewise_fold(cond); folded_cond + Piecewise((2 < y, x < 0), (3 < y, True)) + + When a Boolean containing Piecewise (like cond) or a Piecewise + with Boolean expressions (like folded_cond) is used as a condition, + it is converted to an equivalent :class:`~.ITE` object: + + >>> Piecewise((1, folded_cond)) + Piecewise((1, ITE(x < 0, y > 2, y > 3))) + + When a condition is an ``ITE``, it will be converted to a simplified + Boolean expression: + + >>> piecewise_fold(_) + Piecewise((1, ((x >= 0) | (y > 2)) & ((y > 3) | (x < 0)))) + + See Also + ======== + + piecewise_fold + piecewise_exclusive + ITE + """ + + nargs = None + is_Piecewise = True + + def __new__(cls, *args, **options): + if len(args) == 0: + raise TypeError("At least one (expr, cond) pair expected.") + # (Try to) sympify args first + newargs = [] + for ec in args: + # ec could be a ExprCondPair or a tuple + pair = ExprCondPair(*getattr(ec, 'args', ec)) + cond = pair.cond + if cond is false: + continue + newargs.append(pair) + if cond is true: + break + + eval = options.pop('evaluate', global_parameters.evaluate) + if eval: + r = cls.eval(*newargs) + if r is not None: + return r + elif len(newargs) == 1 and newargs[0].cond == True: + return newargs[0].expr + + return Basic.__new__(cls, *newargs, **options) + + @classmethod + def eval(cls, *_args): + """Either return a modified version of the args or, if no + modifications were made, return None. + + Modifications that are made here: + + 1. relationals are made canonical + 2. any False conditions are dropped + 3. any repeat of a previous condition is ignored + 4. any args past one with a true condition are dropped + + If there are no args left, nan will be returned. + If there is a single arg with a True condition, its + corresponding expression will be returned. + + EXAMPLES + ======== + + >>> from sympy import Piecewise + >>> from sympy.abc import x + >>> cond = -x < -1 + >>> args = [(1, cond), (4, cond), (3, False), (2, True), (5, x < 1)] + >>> Piecewise(*args, evaluate=False) + Piecewise((1, -x < -1), (4, -x < -1), (2, True)) + >>> Piecewise(*args) + Piecewise((1, x > 1), (2, True)) + """ + if not _args: + return Undefined + + if len(_args) == 1 and _args[0][-1] == True: + return _args[0][0] + + newargs = _piecewise_collapse_arguments(_args) + + # some conditions may have been redundant + missing = len(newargs) != len(_args) + # some conditions may have changed + same = all(a == b for a, b in zip(newargs, _args)) + # if either change happened we return the expr with the + # updated args + if not newargs: + raise ValueError(filldedent(''' + There are no conditions (or none that + are not trivially false) to define an + expression.''')) + if missing or not same: + return cls(*newargs) + + def doit(self, **hints): + """ + Evaluate this piecewise function. + """ + newargs = [] + for e, c in self.args: + if hints.get('deep', True): + if isinstance(e, Basic): + newe = e.doit(**hints) + if newe != self: + e = newe + if isinstance(c, Basic): + c = c.doit(**hints) + newargs.append((e, c)) + return self.func(*newargs) + + def _eval_simplify(self, **kwargs): + return piecewise_simplify(self, **kwargs) + + def _eval_as_leading_term(self, x, logx, cdir): + for e, c in self.args: + if c == True or c.subs(x, 0) == True: + return e.as_leading_term(x) + + def _eval_adjoint(self): + return self.func(*[(e.adjoint(), c) for e, c in self.args]) + + def _eval_conjugate(self): + return self.func(*[(e.conjugate(), c) for e, c in self.args]) + + def _eval_derivative(self, x): + return self.func(*[(diff(e, x), c) for e, c in self.args]) + + def _eval_evalf(self, prec): + return self.func(*[(e._evalf(prec), c) for e, c in self.args]) + + def _eval_is_meromorphic(self, x, a): + # Conditions often implicitly assume that the argument is real. + # Hence, there needs to be some check for as_set. + if not a.is_real: + return None + + # Then, scan ExprCondPairs in the given order to find a piece that would contain a, + # possibly as a boundary point. + for e, c in self.args: + cond = c.subs(x, a) + + if cond.is_Relational: + return None + if a in c.as_set().boundary: + return None + # Apply expression if a is an interior point of the domain of e. + if cond: + return e._eval_is_meromorphic(x, a) + + def piecewise_integrate(self, x, **kwargs): + """Return the Piecewise with each expression being + replaced with its antiderivative. To obtain a continuous + antiderivative, use the :func:`~.integrate` function or method. + + Examples + ======== + + >>> from sympy import Piecewise + >>> from sympy.abc import x + >>> p = Piecewise((0, x < 0), (1, x < 1), (2, True)) + >>> p.piecewise_integrate(x) + Piecewise((0, x < 0), (x, x < 1), (2*x, True)) + + Note that this does not give a continuous function, e.g. + at x = 1 the 3rd condition applies and the antiderivative + there is 2*x so the value of the antiderivative is 2: + + >>> anti = _ + >>> anti.subs(x, 1) + 2 + + The continuous derivative accounts for the integral *up to* + the point of interest, however: + + >>> p.integrate(x) + Piecewise((0, x < 0), (x, x < 1), (2*x - 1, True)) + >>> _.subs(x, 1) + 1 + + See Also + ======== + Piecewise._eval_integral + """ + from sympy.integrals import integrate + return self.func(*[(integrate(e, x, **kwargs), c) for e, c in self.args]) + + def _handle_irel(self, x, handler): + """Return either None (if the conditions of self depend only on x) else + a Piecewise expression whose expressions (handled by the handler that + was passed) are paired with the governing x-independent relationals, + e.g. Piecewise((A, a(x) & b(y)), (B, c(x) | c(y)) -> + Piecewise( + (handler(Piecewise((A, a(x) & True), (B, c(x) | True)), b(y) & c(y)), + (handler(Piecewise((A, a(x) & True), (B, c(x) | False)), b(y)), + (handler(Piecewise((A, a(x) & False), (B, c(x) | True)), c(y)), + (handler(Piecewise((A, a(x) & False), (B, c(x) | False)), True)) + """ + # identify governing relationals + rel = self.atoms(Relational) + irel = list(ordered([r for r in rel if x not in r.free_symbols + and r not in (S.true, S.false)])) + if irel: + args = {} + exprinorder = [] + for truth in product((1, 0), repeat=len(irel)): + reps = dict(zip(irel, truth)) + # only store the true conditions since the false are implied + # when they appear lower in the Piecewise args + if 1 not in truth: + cond = None # flag this one so it doesn't get combined + else: + andargs = Tuple(*[i for i in reps if reps[i]]) + free = list(andargs.free_symbols) + if len(free) == 1: + from sympy.solvers.inequalities import ( + reduce_inequalities, _solve_inequality) + try: + t = reduce_inequalities(andargs, free[0]) + # ValueError when there are potentially + # nonvanishing imaginary parts + except (ValueError, NotImplementedError): + # at least isolate free symbol on left + t = And(*[_solve_inequality( + a, free[0], linear=True) + for a in andargs]) + else: + t = And(*andargs) + if t is S.false: + continue # an impossible combination + cond = t + expr = handler(self.xreplace(reps)) + if isinstance(expr, self.func) and len(expr.args) == 1: + expr, econd = expr.args[0] + cond = And(econd, True if cond is None else cond) + # the ec pairs are being collected since all possibilities + # are being enumerated, but don't put the last one in since + # its expr might match a previous expression and it + # must appear last in the args + if cond is not None: + args.setdefault(expr, []).append(cond) + # but since we only store the true conditions we must maintain + # the order so that the expression with the most true values + # comes first + exprinorder.append(expr) + # convert collected conditions as args of Or + for k in args: + args[k] = Or(*args[k]) + # take them in the order obtained + args = [(e, args[e]) for e in uniq(exprinorder)] + # add in the last arg + args.append((expr, True)) + return Piecewise(*args) + + def _eval_integral(self, x, _first=True, **kwargs): + """Return the indefinite integral of the + Piecewise such that subsequent substitution of x with a + value will give the value of the integral (not including + the constant of integration) up to that point. To only + integrate the individual parts of Piecewise, use the + ``piecewise_integrate`` method. + + Examples + ======== + + >>> from sympy import Piecewise + >>> from sympy.abc import x + >>> p = Piecewise((0, x < 0), (1, x < 1), (2, True)) + >>> p.integrate(x) + Piecewise((0, x < 0), (x, x < 1), (2*x - 1, True)) + >>> p.piecewise_integrate(x) + Piecewise((0, x < 0), (x, x < 1), (2*x, True)) + + See Also + ======== + Piecewise.piecewise_integrate + """ + from sympy.integrals.integrals import integrate + + if _first: + def handler(ipw): + if isinstance(ipw, self.func): + return ipw._eval_integral(x, _first=False, **kwargs) + else: + return ipw.integrate(x, **kwargs) + irv = self._handle_irel(x, handler) + if irv is not None: + return irv + + # handle a Piecewise from -oo to oo with and no x-independent relationals + # ----------------------------------------------------------------------- + ok, abei = self._intervals(x) + if not ok: + from sympy.integrals.integrals import Integral + return Integral(self, x) # unevaluated + + pieces = [(a, b) for a, b, _, _ in abei] + oo = S.Infinity + done = [(-oo, oo, -1)] + for k, p in enumerate(pieces): + if p == (-oo, oo): + # all undone intervals will get this key + for j, (a, b, i) in enumerate(done): + if i == -1: + done[j] = a, b, k + break # nothing else to consider + N = len(done) - 1 + for j, (a, b, i) in enumerate(reversed(done)): + if i == -1: + j = N - j + done[j: j + 1] = _clip(p, (a, b), k) + done = [(a, b, i) for a, b, i in done if a != b] + + # append an arg if there is a hole so a reference to + # argument -1 will give Undefined + if any(i == -1 for (a, b, i) in done): + abei.append((-oo, oo, Undefined, -1)) + + # return the sum of the intervals + args = [] + sum = None + for a, b, i in done: + anti = integrate(abei[i][-2], x, **kwargs) + if sum is None: + sum = anti + else: + sum = sum.subs(x, a) + e = anti._eval_interval(x, a, x) + if sum.has(*_illegal) or e.has(*_illegal): + sum = anti + else: + sum += e + # see if we know whether b is contained in original + # condition + if b is S.Infinity: + cond = True + elif self.args[abei[i][-1]].cond.subs(x, b) == False: + cond = (x < b) + else: + cond = (x <= b) + args.append((sum, cond)) + return Piecewise(*args) + + def _eval_interval(self, sym, a, b, _first=True): + """Evaluates the function along the sym in a given interval [a, b]""" + # FIXME: Currently complex intervals are not supported. A possible + # replacement algorithm, discussed in issue 5227, can be found in the + # following papers; + # http://portal.acm.org/citation.cfm?id=281649 + # http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.70.4127&rep=rep1&type=pdf + + if a is None or b is None: + # In this case, it is just simple substitution + return super()._eval_interval(sym, a, b) + else: + x, lo, hi = map(as_Basic, (sym, a, b)) + + if _first: # get only x-dependent relationals + def handler(ipw): + if isinstance(ipw, self.func): + return ipw._eval_interval(x, lo, hi, _first=None) + else: + return ipw._eval_interval(x, lo, hi) + irv = self._handle_irel(x, handler) + if irv is not None: + return irv + + if (lo < hi) is S.false or ( + lo is S.Infinity or hi is S.NegativeInfinity): + rv = self._eval_interval(x, hi, lo, _first=False) + if isinstance(rv, Piecewise): + rv = Piecewise(*[(-e, c) for e, c in rv.args]) + else: + rv = -rv + return rv + + if (lo < hi) is S.true or ( + hi is S.Infinity or lo is S.NegativeInfinity): + pass + else: + _a = Dummy('lo') + _b = Dummy('hi') + a = lo if lo.is_comparable else _a + b = hi if hi.is_comparable else _b + pos = self._eval_interval(x, a, b, _first=False) + if a == _a and b == _b: + # it's purely symbolic so just swap lo and hi and + # change the sign to get the value for when lo > hi + neg, pos = (-pos.xreplace({_a: hi, _b: lo}), + pos.xreplace({_a: lo, _b: hi})) + else: + # at least one of the bounds was comparable, so allow + # _eval_interval to use that information when computing + # the interval with lo and hi reversed + neg, pos = (-self._eval_interval(x, hi, lo, _first=False), + pos.xreplace({_a: lo, _b: hi})) + + # allow simplification based on ordering of lo and hi + p = Dummy('', positive=True) + if lo.is_Symbol: + pos = pos.xreplace({lo: hi - p}).xreplace({p: hi - lo}) + neg = neg.xreplace({lo: hi + p}).xreplace({p: lo - hi}) + elif hi.is_Symbol: + pos = pos.xreplace({hi: lo + p}).xreplace({p: hi - lo}) + neg = neg.xreplace({hi: lo - p}).xreplace({p: lo - hi}) + # evaluate limits that may have unevaluate Min/Max + touch = lambda _: _.replace( + lambda x: isinstance(x, (Min, Max)), + lambda x: x.func(*x.args)) + neg = touch(neg) + pos = touch(pos) + # assemble return expression; make the first condition be Lt + # b/c then the first expression will look the same whether + # the lo or hi limit is symbolic + if a == _a: # the lower limit was symbolic + rv = Piecewise( + (pos, + lo < hi), + (neg, + True)) + else: + rv = Piecewise( + (neg, + hi < lo), + (pos, + True)) + + if rv == Undefined: + raise ValueError("Can't integrate across undefined region.") + if any(isinstance(i, Piecewise) for i in (pos, neg)): + rv = piecewise_fold(rv) + return rv + + # handle a Piecewise with lo <= hi and no x-independent relationals + # ----------------------------------------------------------------- + ok, abei = self._intervals(x) + if not ok: + from sympy.integrals.integrals import Integral + # not being able to do the interval of f(x) can + # be stated as not being able to do the integral + # of f'(x) over the same range + return Integral(self.diff(x), (x, lo, hi)) # unevaluated + + pieces = [(a, b) for a, b, _, _ in abei] + done = [(lo, hi, -1)] + oo = S.Infinity + for k, p in enumerate(pieces): + if p[:2] == (-oo, oo): + # all undone intervals will get this key + for j, (a, b, i) in enumerate(done): + if i == -1: + done[j] = a, b, k + break # nothing else to consider + N = len(done) - 1 + for j, (a, b, i) in enumerate(reversed(done)): + if i == -1: + j = N - j + done[j: j + 1] = _clip(p, (a, b), k) + done = [(a, b, i) for a, b, i in done if a != b] + + # return the sum of the intervals + sum = S.Zero + upto = None + for a, b, i in done: + if i == -1: + if upto is None: + return Undefined + # TODO simplify hi <= upto + return Piecewise((sum, hi <= upto), (Undefined, True)) + sum += abei[i][-2]._eval_interval(x, a, b) + upto = b + return sum + + def _intervals(self, sym, err_on_Eq=False): + r"""Return a bool and a message (when bool is False), else a + list of unique tuples, (a, b, e, i), where a and b + are the lower and upper bounds in which the expression e of + argument i in self is defined and $a < b$ (when involving + numbers) or $a \le b$ when involving symbols. + + If there are any relationals not involving sym, or any + relational cannot be solved for sym, the bool will be False + a message be given as the second return value. The calling + routine should have removed such relationals before calling + this routine. + + The evaluated conditions will be returned as ranges. + Discontinuous ranges will be returned separately with + identical expressions. The first condition that evaluates to + True will be returned as the last tuple with a, b = -oo, oo. + """ + from sympy.solvers.inequalities import _solve_inequality + + assert isinstance(self, Piecewise) + + def nonsymfail(cond): + return False, filldedent(''' + A condition not involving + %s appeared: %s''' % (sym, cond)) + + def _solve_relational(r): + if sym not in r.free_symbols: + return nonsymfail(r) + try: + rv = _solve_inequality(r, sym) + except NotImplementedError: + return False, 'Unable to solve relational %s for %s.' % (r, sym) + if isinstance(rv, Relational): + free = rv.args[1].free_symbols + if rv.args[0] != sym or sym in free: + return False, 'Unable to solve relational %s for %s.' % (r, sym) + if rv.rel_op == '==': + # this equality has been affirmed to have the form + # Eq(sym, rhs) where rhs is sym-free; it represents + # a zero-width interval which will be ignored + # whether it is an isolated condition or contained + # within an And or an Or + rv = S.false + elif rv.rel_op == '!=': + try: + rv = Or(sym < rv.rhs, sym > rv.rhs) + except TypeError: + # e.g. x != I ==> all real x satisfy + rv = S.true + elif rv == (S.NegativeInfinity < sym) & (sym < S.Infinity): + rv = S.true + return True, rv + + args = list(self.args) + # make self canonical wrt Relationals + keys = self.atoms(Relational) + reps = {} + for r in keys: + ok, s = _solve_relational(r) + if ok != True: + return False, ok + reps[r] = s + # process args individually so if any evaluate, their position + # in the original Piecewise will be known + args = [i.xreplace(reps) for i in self.args] + + # precondition args + expr_cond = [] + default = idefault = None + for i, (expr, cond) in enumerate(args): + if cond is S.false: + continue + if cond is S.true: + default = expr + idefault = i + break + if isinstance(cond, Eq): + # unanticipated condition, but it is here in case a + # replacement caused an Eq to appear + if err_on_Eq: + return False, 'encountered Eq condition: %s' % cond + continue # zero width interval + + cond = to_cnf(cond) + if isinstance(cond, And): + cond = distribute_or_over_and(cond) + + if isinstance(cond, Or): + expr_cond.extend( + [(i, expr, o) for o in cond.args + if not isinstance(o, Eq)]) + elif cond is not S.false: + expr_cond.append((i, expr, cond)) + elif cond is S.true: + default = expr + idefault = i + break + + # determine intervals represented by conditions + int_expr = [] + for iarg, expr, cond in expr_cond: + if isinstance(cond, And): + lower = S.NegativeInfinity + upper = S.Infinity + exclude = [] + for cond2 in cond.args: + if not isinstance(cond2, Relational): + return False, 'expecting only Relationals' + if isinstance(cond2, Eq): + lower = upper # ignore + if err_on_Eq: + return False, 'encountered secondary Eq condition' + break + elif isinstance(cond2, Ne): + l, r = cond2.args + if l == sym: + exclude.append(r) + elif r == sym: + exclude.append(l) + else: + return nonsymfail(cond2) + continue + elif cond2.lts == sym: + upper = Min(cond2.gts, upper) + elif cond2.gts == sym: + lower = Max(cond2.lts, lower) + else: + return nonsymfail(cond2) # should never get here + if exclude: + exclude = list(ordered(exclude)) + newcond = [] + for i, e in enumerate(exclude): + if e < lower == True or e > upper == True: + continue + if not newcond: + newcond.append((None, lower)) # add a primer + newcond.append((newcond[-1][1], e)) + newcond.append((newcond[-1][1], upper)) + newcond.pop(0) # remove the primer + expr_cond.extend([(iarg, expr, And(i[0] < sym, sym < i[1])) for i in newcond]) + continue + elif isinstance(cond, Relational) and cond.rel_op != '!=': + lower, upper = cond.lts, cond.gts # part 1: initialize with givens + if cond.lts == sym: # part 1a: expand the side ... + lower = S.NegativeInfinity # e.g. x <= 0 ---> -oo <= 0 + elif cond.gts == sym: # part 1a: ... that can be expanded + upper = S.Infinity # e.g. x >= 0 ---> oo >= 0 + else: + return nonsymfail(cond) + else: + return False, 'unrecognized condition: %s' % cond + + upper = Max(lower, upper) + if err_on_Eq and lower == upper: + return False, 'encountered Eq condition' + if (lower >= upper) is not S.true: + int_expr.append((lower, upper, expr, iarg)) + + if default is not None: + int_expr.append( + (S.NegativeInfinity, S.Infinity, default, idefault)) + + return True, list(uniq(int_expr)) + + def _eval_nseries(self, x, n, logx, cdir=0): + args = [(ec.expr._eval_nseries(x, n, logx), ec.cond) for ec in self.args] + return self.func(*args) + + def _eval_power(self, s): + return self.func(*[(e**s, c) for e, c in self.args]) + + def _eval_subs(self, old, new): + # this is strictly not necessary, but we can keep track + # of whether True or False conditions arise and be + # somewhat more efficient by avoiding other substitutions + # and avoiding invalid conditions that appear after a + # True condition + args = list(self.args) + args_exist = False + for i, (e, c) in enumerate(args): + c = c._subs(old, new) + if c != False: + args_exist = True + e = e._subs(old, new) + args[i] = (e, c) + if c == True: + break + if not args_exist: + args = ((Undefined, True),) + return self.func(*args) + + def _eval_transpose(self): + return self.func(*[(e.transpose(), c) for e, c in self.args]) + + def _eval_template_is_attr(self, is_attr): + b = None + for expr, _ in self.args: + a = getattr(expr, is_attr) + if a is None: + return + if b is None: + b = a + elif b is not a: + return + return b + + _eval_is_finite = lambda self: self._eval_template_is_attr( + 'is_finite') + _eval_is_complex = lambda self: self._eval_template_is_attr('is_complex') + _eval_is_even = lambda self: self._eval_template_is_attr('is_even') + _eval_is_imaginary = lambda self: self._eval_template_is_attr( + 'is_imaginary') + _eval_is_integer = lambda self: self._eval_template_is_attr('is_integer') + _eval_is_irrational = lambda self: self._eval_template_is_attr( + 'is_irrational') + _eval_is_negative = lambda self: self._eval_template_is_attr('is_negative') + _eval_is_nonnegative = lambda self: self._eval_template_is_attr( + 'is_nonnegative') + _eval_is_nonpositive = lambda self: self._eval_template_is_attr( + 'is_nonpositive') + _eval_is_nonzero = lambda self: self._eval_template_is_attr( + 'is_nonzero') + _eval_is_odd = lambda self: self._eval_template_is_attr('is_odd') + _eval_is_polar = lambda self: self._eval_template_is_attr('is_polar') + _eval_is_positive = lambda self: self._eval_template_is_attr('is_positive') + _eval_is_extended_real = lambda self: self._eval_template_is_attr( + 'is_extended_real') + _eval_is_extended_positive = lambda self: self._eval_template_is_attr( + 'is_extended_positive') + _eval_is_extended_negative = lambda self: self._eval_template_is_attr( + 'is_extended_negative') + _eval_is_extended_nonzero = lambda self: self._eval_template_is_attr( + 'is_extended_nonzero') + _eval_is_extended_nonpositive = lambda self: self._eval_template_is_attr( + 'is_extended_nonpositive') + _eval_is_extended_nonnegative = lambda self: self._eval_template_is_attr( + 'is_extended_nonnegative') + _eval_is_real = lambda self: self._eval_template_is_attr('is_real') + _eval_is_zero = lambda self: self._eval_template_is_attr( + 'is_zero') + + @classmethod + def __eval_cond(cls, cond): + """Return the truth value of the condition.""" + if cond == True: + return True + if isinstance(cond, Eq): + try: + diff = cond.lhs - cond.rhs + if diff.is_commutative: + return diff.is_zero + except TypeError: + pass + + def as_expr_set_pairs(self, domain=None): + """Return tuples for each argument of self that give + the expression and the interval in which it is valid + which is contained within the given domain. + If a condition cannot be converted to a set, an error + will be raised. The variable of the conditions is + assumed to be real; sets of real values are returned. + + Examples + ======== + + >>> from sympy import Piecewise, Interval + >>> from sympy.abc import x + >>> p = Piecewise( + ... (1, x < 2), + ... (2,(x > 0) & (x < 4)), + ... (3, True)) + >>> p.as_expr_set_pairs() + [(1, Interval.open(-oo, 2)), + (2, Interval.Ropen(2, 4)), + (3, Interval(4, oo))] + >>> p.as_expr_set_pairs(Interval(0, 3)) + [(1, Interval.Ropen(0, 2)), + (2, Interval(2, 3))] + """ + if domain is None: + domain = S.Reals + exp_sets = [] + U = domain + complex = not domain.is_subset(S.Reals) + cond_free = set() + for expr, cond in self.args: + cond_free |= cond.free_symbols + if len(cond_free) > 1: + raise NotImplementedError(filldedent(''' + multivariate conditions are not handled.''')) + if complex: + for i in cond.atoms(Relational): + if not isinstance(i, (Eq, Ne)): + raise ValueError(filldedent(''' + Inequalities in the complex domain are + not supported. Try the real domain by + setting domain=S.Reals''')) + cond_int = U.intersect(cond.as_set()) + U = U - cond_int + if cond_int != S.EmptySet: + exp_sets.append((expr, cond_int)) + return exp_sets + + def _eval_rewrite_as_ITE(self, *args, **kwargs): + byfree = {} + args = list(args) + default = any(c == True for b, c in args) + for i, (b, c) in enumerate(args): + if not isinstance(b, Boolean) and b != True: + raise TypeError(filldedent(''' + Expecting Boolean or bool but got `%s` + ''' % func_name(b))) + if c == True: + break + # loop over independent conditions for this b + for c in c.args if isinstance(c, Or) else [c]: + free = c.free_symbols + x = free.pop() + try: + byfree[x] = byfree.setdefault( + x, S.EmptySet).union(c.as_set()) + except NotImplementedError: + if not default: + raise NotImplementedError(filldedent(''' + A method to determine whether a multivariate + conditional is consistent with a complete coverage + of all variables has not been implemented so the + rewrite is being stopped after encountering `%s`. + This error would not occur if a default expression + like `(foo, True)` were given. + ''' % c)) + if byfree[x] in (S.UniversalSet, S.Reals): + # collapse the ith condition to True and break + args[i] = list(args[i]) + c = args[i][1] = True + break + if c == True: + break + if c != True: + raise ValueError(filldedent(''' + Conditions must cover all reals or a final default + condition `(foo, True)` must be given. + ''')) + last, _ = args[i] # ignore all past ith arg + for a, c in reversed(args[:i]): + last = ITE(c, a, last) + return _canonical(last) + + def _eval_rewrite_as_KroneckerDelta(self, *args, **kwargs): + from sympy.functions.special.tensor_functions import KroneckerDelta + + rules = { + And: [False, False], + Or: [True, True], + Not: [True, False], + Eq: [None, None], + Ne: [None, None] + } + + class UnrecognizedCondition(Exception): + pass + + def rewrite(cond): + if isinstance(cond, Eq): + return KroneckerDelta(*cond.args) + if isinstance(cond, Ne): + return 1 - KroneckerDelta(*cond.args) + + cls, args = type(cond), cond.args + if cls not in rules: + raise UnrecognizedCondition(cls) + + b1, b2 = rules[cls] + k = Mul(*[1 - rewrite(c) for c in args]) if b1 else Mul(*[rewrite(c) for c in args]) + + if b2: + return 1 - k + return k + + conditions = [] + true_value = None + for value, cond in args: + if type(cond) in rules: + conditions.append((value, cond)) + elif cond is S.true: + if true_value is None: + true_value = value + else: + return + + if true_value is not None: + result = true_value + + for value, cond in conditions[::-1]: + try: + k = rewrite(cond) + result = k * value + (1 - k) * result + except UnrecognizedCondition: + return + + return result + + +def piecewise_fold(expr, evaluate=True): + """ + Takes an expression containing a piecewise function and returns the + expression in piecewise form. In addition, any ITE conditions are + rewritten in negation normal form and simplified. + + The final Piecewise is evaluated (default) but if the raw form + is desired, send ``evaluate=False``; if trivial evaluation is + desired, send ``evaluate=None`` and duplicate conditions and + processing of True and False will be handled. + + Examples + ======== + + >>> from sympy import Piecewise, piecewise_fold, S + >>> from sympy.abc import x + >>> p = Piecewise((x, x < 1), (1, S(1) <= x)) + >>> piecewise_fold(x*p) + Piecewise((x**2, x < 1), (x, True)) + + See Also + ======== + + Piecewise + piecewise_exclusive + """ + if not isinstance(expr, Basic) or not expr.has(Piecewise): + return expr + + new_args = [] + if isinstance(expr, (ExprCondPair, Piecewise)): + for e, c in expr.args: + if not isinstance(e, Piecewise): + e = piecewise_fold(e) + # we don't keep Piecewise in condition because + # it has to be checked to see that it's complete + # and we convert it to ITE at that time + assert not c.has(Piecewise) # pragma: no cover + if isinstance(c, ITE): + c = c.to_nnf() + c = simplify_logic(c, form='cnf') + if isinstance(e, Piecewise): + new_args.extend([(piecewise_fold(ei), And(ci, c)) + for ei, ci in e.args]) + else: + new_args.append((e, c)) + else: + # Given + # P1 = Piecewise((e11, c1), (e12, c2), A) + # P2 = Piecewise((e21, c1), (e22, c2), B) + # ... + # the folding of f(P1, P2) is trivially + # Piecewise( + # (f(e11, e21), c1), + # (f(e12, e22), c2), + # (f(Piecewise(A), Piecewise(B)), True)) + # Certain objects end up rewriting themselves as thus, so + # we do that grouping before the more generic folding. + # The following applies this idea when f = Add or f = Mul + # (and the expression is commutative). + if expr.is_Add or expr.is_Mul and expr.is_commutative: + p, args = sift(expr.args, lambda x: x.is_Piecewise, binary=True) + pc = sift(p, lambda x: tuple([c for e,c in x.args])) + for c in list(ordered(pc)): + if len(pc[c]) > 1: + pargs = [list(i.args) for i in pc[c]] + # the first one is the same; there may be more + com = common_prefix(*[ + [i.cond for i in j] for j in pargs]) + n = len(com) + collected = [] + for i in range(n): + collected.append(( + expr.func(*[ai[i].expr for ai in pargs]), + com[i])) + remains = [] + for a in pargs: + if n == len(a): # no more args + continue + if a[n].cond == True: # no longer Piecewise + remains.append(a[n].expr) + else: # restore the remaining Piecewise + remains.append( + Piecewise(*a[n:], evaluate=False)) + if remains: + collected.append((expr.func(*remains), True)) + args.append(Piecewise(*collected, evaluate=False)) + continue + args.extend(pc[c]) + else: + args = expr.args + # fold + folded = list(map(piecewise_fold, args)) + for ec in product(*[ + (i.args if isinstance(i, Piecewise) else + [(i, true)]) for i in folded]): + e, c = zip(*ec) + new_args.append((expr.func(*e), And(*c))) + + if evaluate is None: + # don't return duplicate conditions, otherwise don't evaluate + new_args = list(reversed([(e, c) for c, e in { + c: e for e, c in reversed(new_args)}.items()])) + rv = Piecewise(*new_args, evaluate=evaluate) + if evaluate is None and len(rv.args) == 1 and rv.args[0].cond == True: + return rv.args[0].expr + if any(s.expr.has(Piecewise) for p in rv.atoms(Piecewise) for s in p.args): + return piecewise_fold(rv) + return rv + + +def _clip(A, B, k): + """Return interval B as intervals that are covered by A (keyed + to k) and all other intervals of B not covered by A keyed to -1. + + The reference point of each interval is the rhs; if the lhs is + greater than the rhs then an interval of zero width interval will + result, e.g. (4, 1) is treated like (1, 1). + + Examples + ======== + + >>> from sympy.functions.elementary.piecewise import _clip + >>> from sympy import Tuple + >>> A = Tuple(1, 3) + >>> B = Tuple(2, 4) + >>> _clip(A, B, 0) + [(2, 3, 0), (3, 4, -1)] + + Interpretation: interval portion (2, 3) of interval (2, 4) is + covered by interval (1, 3) and is keyed to 0 as requested; + interval (3, 4) was not covered by (1, 3) and is keyed to -1. + """ + a, b = B + c, d = A + c, d = Min(Max(c, a), b), Min(Max(d, a), b) + a = Min(a, b) + p = [] + if a != c: + p.append((a, c, -1)) + else: + pass + if c != d: + p.append((c, d, k)) + else: + pass + if b != d: + if d == c and p and p[-1][-1] == -1: + p[-1] = p[-1][0], b, -1 + else: + p.append((d, b, -1)) + else: + pass + + return p + + +def piecewise_simplify_arguments(expr, **kwargs): + from sympy.simplify.simplify import simplify + + # simplify conditions + f1 = expr.args[0].cond.free_symbols + args = None + if len(f1) == 1 and not expr.atoms(Eq): + x = f1.pop() + # this won't return intervals involving Eq + # and it won't handle symbols treated as + # booleans + ok, abe_ = expr._intervals(x, err_on_Eq=True) + def include(c, x, a): + "return True if c.subs(x, a) is True, else False" + try: + return c.subs(x, a) == True + except TypeError: + return False + if ok: + args = [] + covered = S.EmptySet + from sympy.sets.sets import Interval + for a, b, e, i in abe_: + c = expr.args[i].cond + incl_a = include(c, x, a) + incl_b = include(c, x, b) + iv = Interval(a, b, not incl_a, not incl_b) + cset = iv - covered + if not cset: + continue + try: + a = cset.inf + except NotImplementedError: + pass # continue with the given `a` + else: + incl_a = include(c, x, a) + if incl_a and incl_b: + if a.is_infinite and b.is_infinite: + c = S.true + elif b.is_infinite: + c = (x > a) if a in covered else (x >= a) + elif a.is_infinite: + c = (x <= b) + elif a in covered: + c = And(a < x, x <= b) + else: + c = And(a <= x, x <= b) + elif incl_a: + if a.is_infinite: + c = (x < b) + elif a in covered: + c = And(a < x, x < b) + else: + c = And(a <= x, x < b) + elif incl_b: + if b.is_infinite: + c = (x > a) + else: + c = And(a < x, x <= b) + else: + if a in covered: + c = (x < b) + else: + c = And(a < x, x < b) + covered |= iv + if a is S.NegativeInfinity and incl_a: + covered |= {S.NegativeInfinity} + if b is S.Infinity and incl_b: + covered |= {S.Infinity} + args.append((e, c)) + if not S.Reals.is_subset(covered): + args.append((Undefined, True)) + if args is None: + args = list(expr.args) + for i in range(len(args)): + e, c = args[i] + if isinstance(c, Basic): + c = simplify(c, **kwargs) + args[i] = (e, c) + + # simplify expressions + doit = kwargs.pop('doit', None) + for i in range(len(args)): + e, c = args[i] + if isinstance(e, Basic): + # Skip doit to avoid growth at every call for some integrals + # and sums, see sympy/sympy#17165 + newe = simplify(e, doit=False, **kwargs) + if newe != e: + e = newe + args[i] = (e, c) + + # restore kwargs flag + if doit is not None: + kwargs['doit'] = doit + + return Piecewise(*args) + + +def _piecewise_collapse_arguments(_args): + newargs = [] # the unevaluated conditions + current_cond = set() # the conditions up to a given e, c pair + for expr, cond in _args: + cond = cond.replace( + lambda _: _.is_Relational, _canonical_coeff) + # Check here if expr is a Piecewise and collapse if one of + # the conds in expr matches cond. This allows the collapsing + # of Piecewise((Piecewise((x,x<0)),x<0)) to Piecewise((x,x<0)). + # This is important when using piecewise_fold to simplify + # multiple Piecewise instances having the same conds. + # Eventually, this code should be able to collapse Piecewise's + # having different intervals, but this will probably require + # using the new assumptions. + if isinstance(expr, Piecewise): + unmatching = [] + for i, (e, c) in enumerate(expr.args): + if c in current_cond: + # this would already have triggered + continue + if c == cond: + if c != True: + # nothing past this condition will ever + # trigger and only those args before this + # that didn't match a previous condition + # could possibly trigger + if unmatching: + expr = Piecewise(*( + unmatching + [(e, c)])) + else: + expr = e + break + else: + unmatching.append((e, c)) + + # check for condition repeats + got = False + # -- if an And contains a condition that was + # already encountered, then the And will be + # False: if the previous condition was False + # then the And will be False and if the previous + # condition is True then then we wouldn't get to + # this point. In either case, we can skip this condition. + for i in ([cond] + + (list(cond.args) if isinstance(cond, And) else + [])): + if i in current_cond: + got = True + break + if got: + continue + + # -- if not(c) is already in current_cond then c is + # a redundant condition in an And. This does not + # apply to Or, however: (e1, c), (e2, Or(~c, d)) + # is not (e1, c), (e2, d) because if c and d are + # both False this would give no results when the + # true answer should be (e2, True) + if isinstance(cond, And): + nonredundant = [] + for c in cond.args: + if isinstance(c, Relational): + if c.negated.canonical in current_cond: + continue + # if a strict inequality appears after + # a non-strict one, then the condition is + # redundant + if isinstance(c, (Lt, Gt)) and ( + c.weak in current_cond): + cond = False + break + nonredundant.append(c) + else: + cond = cond.func(*nonredundant) + elif isinstance(cond, Relational): + if cond.negated.canonical in current_cond: + cond = S.true + + current_cond.add(cond) + + # collect successive e,c pairs when exprs or cond match + if newargs: + if newargs[-1].expr == expr: + orcond = Or(cond, newargs[-1].cond) + if isinstance(orcond, (And, Or)): + orcond = distribute_and_over_or(orcond) + newargs[-1] = ExprCondPair(expr, orcond) + continue + elif newargs[-1].cond == cond: + continue + newargs.append(ExprCondPair(expr, cond)) + return newargs + + +_blessed = lambda e: getattr(e.lhs, '_diff_wrt', False) and ( + getattr(e.rhs, '_diff_wrt', None) or + isinstance(e.rhs, (Rational, NumberSymbol))) + + +def piecewise_simplify(expr, **kwargs): + expr = piecewise_simplify_arguments(expr, **kwargs) + if not isinstance(expr, Piecewise): + return expr + args = list(expr.args) + + args = _piecewise_simplify_eq_and(args) + args = _piecewise_simplify_equal_to_next_segment(args) + return Piecewise(*args) + + +def _piecewise_simplify_equal_to_next_segment(args): + """ + See if expressions valid for an Equal expression happens to evaluate + to the same function as in the next piecewise segment, see: + https://github.com/sympy/sympy/issues/8458 + """ + prevexpr = None + for i, (expr, cond) in reversed(list(enumerate(args))): + if prevexpr is not None: + if isinstance(cond, And): + eqs, other = sift(cond.args, + lambda i: isinstance(i, Eq), binary=True) + elif isinstance(cond, Eq): + eqs, other = [cond], [] + else: + eqs = other = [] + _prevexpr = prevexpr + _expr = expr + if eqs and not other: + eqs = list(ordered(eqs)) + for e in eqs: + # allow 2 args to collapse into 1 for any e + # otherwise limit simplification to only simple-arg + # Eq instances + if len(args) == 2 or _blessed(e): + _prevexpr = _prevexpr.subs(*e.args) + _expr = _expr.subs(*e.args) + # Did it evaluate to the same? + if _prevexpr == _expr: + # Set the expression for the Not equal section to the same + # as the next. These will be merged when creating the new + # Piecewise + args[i] = args[i].func(args[i + 1][0], cond) + else: + # Update the expression that we compare against + prevexpr = expr + else: + prevexpr = expr + return args + + +def _piecewise_simplify_eq_and(args): + """ + Try to simplify conditions and the expression for + equalities that are part of the condition, e.g. + Piecewise((n, And(Eq(n,0), Eq(n + m, 0))), (1, True)) + -> Piecewise((0, And(Eq(n, 0), Eq(m, 0))), (1, True)) + """ + for i, (expr, cond) in enumerate(args): + if isinstance(cond, And): + eqs, other = sift(cond.args, + lambda i: isinstance(i, Eq), binary=True) + elif isinstance(cond, Eq): + eqs, other = [cond], [] + else: + eqs = other = [] + if eqs: + eqs = list(ordered(eqs)) + for j, e in enumerate(eqs): + # these blessed lhs objects behave like Symbols + # and the rhs are simple replacements for the "symbols" + if _blessed(e): + expr = expr.subs(*e.args) + eqs[j + 1:] = [ei.subs(*e.args) for ei in eqs[j + 1:]] + other = [ei.subs(*e.args) for ei in other] + cond = And(*(eqs + other)) + args[i] = args[i].func(expr, cond) + return args + + +def piecewise_exclusive(expr, *, skip_nan=False, deep=True): + """ + Rewrite :class:`Piecewise` with mutually exclusive conditions. + + Explanation + =========== + + SymPy represents the conditions of a :class:`Piecewise` in an + "if-elif"-fashion, allowing more than one condition to be simultaneously + True. The interpretation is that the first condition that is True is the + case that holds. While this is a useful representation computationally it + is not how a piecewise formula is typically shown in a mathematical text. + The :func:`piecewise_exclusive` function can be used to rewrite any + :class:`Piecewise` with more typical mutually exclusive conditions. + + Note that further manipulation of the resulting :class:`Piecewise`, e.g. + simplifying it, will most likely make it non-exclusive. Hence, this is + primarily a function to be used in conjunction with printing the Piecewise + or if one would like to reorder the expression-condition pairs. + + If it is not possible to determine that all possibilities are covered by + the different cases of the :class:`Piecewise` then a final + :class:`~sympy.core.numbers.NaN` case will be included explicitly. This + can be prevented by passing ``skip_nan=True``. + + Examples + ======== + + >>> from sympy import piecewise_exclusive, Symbol, Piecewise, S + >>> x = Symbol('x', real=True) + >>> p = Piecewise((0, x < 0), (S.Half, x <= 0), (1, True)) + >>> piecewise_exclusive(p) + Piecewise((0, x < 0), (1/2, Eq(x, 0)), (1, x > 0)) + >>> piecewise_exclusive(Piecewise((2, x > 1))) + Piecewise((2, x > 1), (nan, x <= 1)) + >>> piecewise_exclusive(Piecewise((2, x > 1)), skip_nan=True) + Piecewise((2, x > 1)) + + Parameters + ========== + + expr: a SymPy expression. + Any :class:`Piecewise` in the expression will be rewritten. + skip_nan: ``bool`` (default ``False``) + If ``skip_nan`` is set to ``True`` then a final + :class:`~sympy.core.numbers.NaN` case will not be included. + deep: ``bool`` (default ``True``) + If ``deep`` is ``True`` then :func:`piecewise_exclusive` will rewrite + any :class:`Piecewise` subexpressions in ``expr`` rather than just + rewriting ``expr`` itself. + + Returns + ======= + + An expression equivalent to ``expr`` but where all :class:`Piecewise` have + been rewritten with mutually exclusive conditions. + + See Also + ======== + + Piecewise + piecewise_fold + """ + + def make_exclusive(*pwargs): + + cumcond = false + newargs = [] + + # Handle the first n-1 cases + for expr_i, cond_i in pwargs[:-1]: + cancond = And(cond_i, Not(cumcond)).simplify() + cumcond = Or(cond_i, cumcond).simplify() + newargs.append((expr_i, cancond)) + + # For the nth case defer simplification of cumcond + expr_n, cond_n = pwargs[-1] + cancond_n = And(cond_n, Not(cumcond)).simplify() + newargs.append((expr_n, cancond_n)) + + if not skip_nan: + cumcond = Or(cond_n, cumcond).simplify() + if cumcond is not true: + newargs.append((Undefined, Not(cumcond).simplify())) + + return Piecewise(*newargs, evaluate=False) + + if deep: + return expr.replace(Piecewise, make_exclusive) + elif isinstance(expr, Piecewise): + return make_exclusive(*expr.args) + else: + return expr diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_complexes.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_complexes.py new file mode 100644 index 0000000000000000000000000000000000000000..699c0fef966c99147b713aaa80710b7b8cf21c73 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_complexes.py @@ -0,0 +1,1030 @@ +from sympy.core.function import (Derivative, Function, Lambda, expand, PoleError) +from sympy.core.numbers import (E, I, Rational, comp, nan, oo, pi, zoo) +from sympy.core.relational import Eq +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.complexes import (Abs, adjoint, arg, conjugate, im, re, sign, transpose) +from sympy.functions.elementary.exponential import (exp, exp_polar, log) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import (acos, atan, atan2, cos, sin) +from sympy.functions.elementary.hyperbolic import sinh +from sympy.functions.special.delta_functions import (DiracDelta, Heaviside) +from sympy.integrals.integrals import Integral +from sympy.matrices.dense import Matrix +from sympy.matrices.expressions.funcmatrix import FunctionMatrix +from sympy.matrices.expressions.matexpr import MatrixSymbol +from sympy.matrices.immutable import (ImmutableMatrix, ImmutableSparseMatrix) +from sympy.matrices import SparseMatrix +from sympy.sets.sets import Interval +from sympy.core.expr import unchanged +from sympy.core.function import ArgumentIndexError +from sympy.series.order import Order +from sympy.testing.pytest import XFAIL, raises, _both_exp_pow + + +def N_equals(a, b): + """Check whether two complex numbers are numerically close""" + return comp(a.n(), b.n(), 1.e-6) + + +def test_re(): + x, y = symbols('x,y') + a, b = symbols('a,b', real=True) + + r = Symbol('r', real=True) + i = Symbol('i', imaginary=True) + + assert re(nan) is nan + + assert re(oo) is oo + assert re(-oo) is -oo + + assert re(0) == 0 + + assert re(1) == 1 + assert re(-1) == -1 + + assert re(E) == E + assert re(-E) == -E + + assert unchanged(re, x) + assert re(x*I) == -im(x) + assert re(r*I) == 0 + assert re(r) == r + assert re(i*I) == I * i + assert re(i) == 0 + + assert re(x + y) == re(x) + re(y) + assert re(x + r) == re(x) + r + + assert re(re(x)) == re(x) + + assert re(2 + I) == 2 + assert re(x + I) == re(x) + + assert re(x + y*I) == re(x) - im(y) + assert re(x + r*I) == re(x) + + assert re(log(2*I)) == log(2) + + assert re((2 + I)**2).expand(complex=True) == 3 + + assert re(conjugate(x)) == re(x) + assert conjugate(re(x)) == re(x) + + assert re(x).as_real_imag() == (re(x), 0) + + assert re(i*r*x).diff(r) == re(i*x) + assert re(i*r*x).diff(i) == I*r*im(x) + + assert re( + sqrt(a + b*I)) == (a**2 + b**2)**Rational(1, 4)*cos(atan2(b, a)/2) + assert re(a * (2 + b*I)) == 2*a + + assert re((1 + sqrt(a + b*I))/2) == \ + (a**2 + b**2)**Rational(1, 4)*cos(atan2(b, a)/2)/2 + S.Half + + assert re(x).rewrite(im) == x - S.ImaginaryUnit*im(x) + assert (x + re(y)).rewrite(re, im) == x + y - S.ImaginaryUnit*im(y) + + a = Symbol('a', algebraic=True) + t = Symbol('t', transcendental=True) + x = Symbol('x') + assert re(a).is_algebraic + assert re(x).is_algebraic is None + assert re(t).is_algebraic is False + + assert re(S.ComplexInfinity) is S.NaN + + n, m, l = symbols('n m l') + A = MatrixSymbol('A',n,m) + assert re(A) == (S.Half) * (A + conjugate(A)) + + A = Matrix([[1 + 4*I,2],[0, -3*I]]) + assert re(A) == Matrix([[1, 2],[0, 0]]) + + A = ImmutableMatrix([[1 + 3*I, 3-2*I],[0, 2*I]]) + assert re(A) == ImmutableMatrix([[1, 3],[0, 0]]) + + X = SparseMatrix([[2*j + i*I for i in range(5)] for j in range(5)]) + assert re(X) - Matrix([[0, 0, 0, 0, 0], + [2, 2, 2, 2, 2], + [4, 4, 4, 4, 4], + [6, 6, 6, 6, 6], + [8, 8, 8, 8, 8]]) == Matrix.zeros(5) + + assert im(X) - Matrix([[0, 1, 2, 3, 4], + [0, 1, 2, 3, 4], + [0, 1, 2, 3, 4], + [0, 1, 2, 3, 4], + [0, 1, 2, 3, 4]]) == Matrix.zeros(5) + + X = FunctionMatrix(3, 3, Lambda((n, m), n + m*I)) + assert re(X) == Matrix([[0, 0, 0], [1, 1, 1], [2, 2, 2]]) + + +def test_im(): + x, y = symbols('x,y') + a, b = symbols('a,b', real=True) + + r = Symbol('r', real=True) + i = Symbol('i', imaginary=True) + + assert im(nan) is nan + + assert im(oo*I) is oo + assert im(-oo*I) is -oo + + assert im(0) == 0 + + assert im(1) == 0 + assert im(-1) == 0 + + assert im(E*I) == E + assert im(-E*I) == -E + + assert unchanged(im, x) + assert im(x*I) == re(x) + assert im(r*I) == r + assert im(r) == 0 + assert im(i*I) == 0 + assert im(i) == -I * i + + assert im(x + y) == im(x) + im(y) + assert im(x + r) == im(x) + assert im(x + r*I) == im(x) + r + + assert im(im(x)*I) == im(x) + + assert im(2 + I) == 1 + assert im(x + I) == im(x) + 1 + + assert im(x + y*I) == im(x) + re(y) + assert im(x + r*I) == im(x) + r + + assert im(log(2*I)) == pi/2 + + assert im((2 + I)**2).expand(complex=True) == 4 + + assert im(conjugate(x)) == -im(x) + assert conjugate(im(x)) == im(x) + + assert im(x).as_real_imag() == (im(x), 0) + + assert im(i*r*x).diff(r) == im(i*x) + assert im(i*r*x).diff(i) == -I * re(r*x) + + assert im( + sqrt(a + b*I)) == (a**2 + b**2)**Rational(1, 4)*sin(atan2(b, a)/2) + assert im(a * (2 + b*I)) == a*b + + assert im((1 + sqrt(a + b*I))/2) == \ + (a**2 + b**2)**Rational(1, 4)*sin(atan2(b, a)/2)/2 + + assert im(x).rewrite(re) == -S.ImaginaryUnit * (x - re(x)) + assert (x + im(y)).rewrite(im, re) == x - S.ImaginaryUnit * (y - re(y)) + + a = Symbol('a', algebraic=True) + t = Symbol('t', transcendental=True) + x = Symbol('x') + assert re(a).is_algebraic + assert re(x).is_algebraic is None + assert re(t).is_algebraic is False + + assert im(S.ComplexInfinity) is S.NaN + + n, m, l = symbols('n m l') + A = MatrixSymbol('A',n,m) + + assert im(A) == (S.One/(2*I)) * (A - conjugate(A)) + + A = Matrix([[1 + 4*I, 2],[0, -3*I]]) + assert im(A) == Matrix([[4, 0],[0, -3]]) + + A = ImmutableMatrix([[1 + 3*I, 3-2*I],[0, 2*I]]) + assert im(A) == ImmutableMatrix([[3, -2],[0, 2]]) + + X = ImmutableSparseMatrix( + [[i*I + i for i in range(5)] for i in range(5)]) + Y = SparseMatrix([list(range(5)) for i in range(5)]) + assert im(X).as_immutable() == Y + + X = FunctionMatrix(3, 3, Lambda((n, m), n + m*I)) + assert im(X) == Matrix([[0, 1, 2], [0, 1, 2], [0, 1, 2]]) + +def test_sign(): + assert sign(1.2) == 1 + assert sign(-1.2) == -1 + assert sign(3*I) == I + assert sign(-3*I) == -I + assert sign(0) == 0 + assert sign(0, evaluate=False).doit() == 0 + assert sign(oo, evaluate=False).doit() == 1 + assert sign(nan) is nan + assert sign(2 + 2*I).doit() == sqrt(2)*(2 + 2*I)/4 + assert sign(2 + 3*I).simplify() == sign(2 + 3*I) + assert sign(2 + 2*I).simplify() == sign(1 + I) + assert sign(im(sqrt(1 - sqrt(3)))) == 1 + assert sign(sqrt(1 - sqrt(3))) == I + + x = Symbol('x') + assert sign(x).is_finite is True + assert sign(x).is_complex is True + assert sign(x).is_imaginary is None + assert sign(x).is_integer is None + assert sign(x).is_real is None + assert sign(x).is_zero is None + assert sign(x).doit() == sign(x) + assert sign(1.2*x) == sign(x) + assert sign(2*x) == sign(x) + assert sign(I*x) == I*sign(x) + assert sign(-2*I*x) == -I*sign(x) + assert sign(conjugate(x)) == conjugate(sign(x)) + + p = Symbol('p', positive=True) + n = Symbol('n', negative=True) + m = Symbol('m', negative=True) + assert sign(2*p*x) == sign(x) + assert sign(n*x) == -sign(x) + assert sign(n*m*x) == sign(x) + + x = Symbol('x', imaginary=True) + assert sign(x).is_imaginary is True + assert sign(x).is_integer is False + assert sign(x).is_real is False + assert sign(x).is_zero is False + assert sign(x).diff(x) == 2*DiracDelta(-I*x) + assert sign(x).doit() == x / Abs(x) + assert conjugate(sign(x)) == -sign(x) + + x = Symbol('x', real=True) + assert sign(x).is_imaginary is False + assert sign(x).is_integer is True + assert sign(x).is_real is True + assert sign(x).is_zero is None + assert sign(x).diff(x) == 2*DiracDelta(x) + assert sign(x).doit() == sign(x) + assert conjugate(sign(x)) == sign(x) + + x = Symbol('x', nonzero=True) + assert sign(x).is_imaginary is False + assert sign(x).is_integer is True + assert sign(x).is_real is True + assert sign(x).is_zero is False + assert sign(x).doit() == x / Abs(x) + assert sign(Abs(x)) == 1 + assert Abs(sign(x)) == 1 + + x = Symbol('x', positive=True) + assert sign(x).is_imaginary is False + assert sign(x).is_integer is True + assert sign(x).is_real is True + assert sign(x).is_zero is False + assert sign(x).doit() == x / Abs(x) + assert sign(Abs(x)) == 1 + assert Abs(sign(x)) == 1 + + x = 0 + assert sign(x).is_imaginary is False + assert sign(x).is_integer is True + assert sign(x).is_real is True + assert sign(x).is_zero is True + assert sign(x).doit() == 0 + assert sign(Abs(x)) == 0 + assert Abs(sign(x)) == 0 + + nz = Symbol('nz', nonzero=True, integer=True) + assert sign(nz).is_imaginary is False + assert sign(nz).is_integer is True + assert sign(nz).is_real is True + assert sign(nz).is_zero is False + assert sign(nz)**2 == 1 + assert (sign(nz)**3).args == (sign(nz), 3) + + assert sign(Symbol('x', nonnegative=True)).is_nonnegative + assert sign(Symbol('x', nonnegative=True)).is_nonpositive is None + assert sign(Symbol('x', nonpositive=True)).is_nonnegative is None + assert sign(Symbol('x', nonpositive=True)).is_nonpositive + assert sign(Symbol('x', real=True)).is_nonnegative is None + assert sign(Symbol('x', real=True)).is_nonpositive is None + assert sign(Symbol('x', real=True, zero=False)).is_nonpositive is None + + x, y = Symbol('x', real=True), Symbol('y') + f = Function('f') + assert sign(x).rewrite(Piecewise) == \ + Piecewise((1, x > 0), (-1, x < 0), (0, True)) + assert sign(y).rewrite(Piecewise) == sign(y) + assert sign(x).rewrite(Heaviside) == 2*Heaviside(x, H0=S(1)/2) - 1 + assert sign(y).rewrite(Heaviside) == sign(y) + assert sign(y).rewrite(Abs) == Piecewise((0, Eq(y, 0)), (y/Abs(y), True)) + assert sign(f(y)).rewrite(Abs) == Piecewise((0, Eq(f(y), 0)), (f(y)/Abs(f(y)), True)) + + # evaluate what can be evaluated + assert sign(exp_polar(I*pi)*pi) is S.NegativeOne + + eq = -sqrt(10 + 6*sqrt(3)) + sqrt(1 + sqrt(3)) + sqrt(3 + 3*sqrt(3)) + # if there is a fast way to know when and when you cannot prove an + # expression like this is zero then the equality to zero is ok + assert sign(eq).func is sign or sign(eq) == 0 + # but sometimes it's hard to do this so it's better not to load + # abs down with tests that will be very slow + q = 1 + sqrt(2) - 2*sqrt(3) + 1331*sqrt(6) + p = expand(q**3)**Rational(1, 3) + d = p - q + assert sign(d).func is sign or sign(d) == 0 + + +def test_as_real_imag(): + n = pi**1000 + # the special code for working out the real + # and complex parts of a power with Integer exponent + # should not run if there is no imaginary part, hence + # this should not hang + assert n.as_real_imag() == (n, 0) + + # issue 6261 + x = Symbol('x') + assert sqrt(x).as_real_imag() == \ + ((re(x)**2 + im(x)**2)**Rational(1, 4)*cos(atan2(im(x), re(x))/2), + (re(x)**2 + im(x)**2)**Rational(1, 4)*sin(atan2(im(x), re(x))/2)) + + # issue 3853 + a, b = symbols('a,b', real=True) + assert ((1 + sqrt(a + b*I))/2).as_real_imag() == \ + ( + (a**2 + b**2)**Rational( + 1, 4)*cos(atan2(b, a)/2)/2 + S.Half, + (a**2 + b**2)**Rational(1, 4)*sin(atan2(b, a)/2)/2) + + assert sqrt(a**2).as_real_imag() == (sqrt(a**2), 0) + i = symbols('i', imaginary=True) + assert sqrt(i**2).as_real_imag() == (0, abs(i)) + + assert ((1 + I)/(1 - I)).as_real_imag() == (0, 1) + assert ((1 + I)**3/(1 - I)).as_real_imag() == (-2, 0) + + +@XFAIL +def test_sign_issue_3068(): + n = pi**1000 + i = int(n) + x = Symbol('x') + assert (n - i).round() == 1 # doesn't hang + assert sign(n - i) == 1 + # perhaps it's not possible to get the sign right when + # only 1 digit is being requested for this situation; + # 2 digits works + assert (n - x).n(1, subs={x: i}) > 0 + assert (n - x).n(2, subs={x: i}) > 0 + + +def test_Abs(): + raises(TypeError, lambda: Abs(Interval(2, 3))) # issue 8717 + + x, y = symbols('x,y') + assert sign(sign(x)) == sign(x) + assert sign(x*y).func is sign + assert Abs(0) == 0 + assert Abs(1) == 1 + assert Abs(-1) == 1 + assert Abs(I) == 1 + assert Abs(-I) == 1 + assert Abs(nan) is nan + assert Abs(zoo) is oo + assert Abs(I * pi) == pi + assert Abs(-I * pi) == pi + assert Abs(I * x) == Abs(x) + assert Abs(-I * x) == Abs(x) + assert Abs(-2*x) == 2*Abs(x) + assert Abs(-2.0*x) == 2.0*Abs(x) + assert Abs(2*pi*x*y) == 2*pi*Abs(x*y) + assert Abs(conjugate(x)) == Abs(x) + assert conjugate(Abs(x)) == Abs(x) + assert Abs(x).expand(complex=True) == sqrt(re(x)**2 + im(x)**2) + + a = Symbol('a', positive=True) + assert Abs(2*pi*x*a) == 2*pi*a*Abs(x) + assert Abs(2*pi*I*x*a) == 2*pi*a*Abs(x) + + x = Symbol('x', real=True) + n = Symbol('n', integer=True) + assert Abs((-1)**n) == 1 + assert x**(2*n) == Abs(x)**(2*n) + assert Abs(x).diff(x) == sign(x) + assert abs(x) == Abs(x) # Python built-in + assert Abs(x)**3 == x**2*Abs(x) + assert Abs(x)**4 == x**4 + assert ( + Abs(x)**(3*n)).args == (Abs(x), 3*n) # leave symbolic odd unchanged + assert (1/Abs(x)).args == (Abs(x), -1) + assert 1/Abs(x)**3 == 1/(x**2*Abs(x)) + assert Abs(x)**-3 == Abs(x)/(x**4) + assert Abs(x**3) == x**2*Abs(x) + assert Abs(I**I) == exp(-pi/2) + assert Abs((4 + 5*I)**(6 + 7*I)) == 68921*exp(-7*atan(Rational(5, 4))) + y = Symbol('y', real=True) + assert Abs(I**y) == 1 + y = Symbol('y') + assert Abs(I**y) == exp(-pi*im(y)/2) + + x = Symbol('x', imaginary=True) + assert Abs(x).diff(x) == -sign(x) + + eq = -sqrt(10 + 6*sqrt(3)) + sqrt(1 + sqrt(3)) + sqrt(3 + 3*sqrt(3)) + # if there is a fast way to know when you can and when you cannot prove an + # expression like this is zero then the equality to zero is ok + assert abs(eq).func is Abs or abs(eq) == 0 + # but sometimes it's hard to do this so it's better not to load + # abs down with tests that will be very slow + q = 1 + sqrt(2) - 2*sqrt(3) + 1331*sqrt(6) + p = expand(q**3)**Rational(1, 3) + d = p - q + assert abs(d).func is Abs or abs(d) == 0 + + assert Abs(4*exp(pi*I/4)) == 4 + assert Abs(3**(2 + I)) == 9 + assert Abs((-3)**(1 - I)) == 3*exp(pi) + + assert Abs(oo) is oo + assert Abs(-oo) is oo + assert Abs(oo + I) is oo + assert Abs(oo + I*oo) is oo + + a = Symbol('a', algebraic=True) + t = Symbol('t', transcendental=True) + x = Symbol('x') + assert re(a).is_algebraic + assert re(x).is_algebraic is None + assert re(t).is_algebraic is False + assert Abs(x).fdiff() == sign(x) + raises(ArgumentIndexError, lambda: Abs(x).fdiff(2)) + + # doesn't have recursion error + arg = sqrt(acos(1 - I)*acos(1 + I)) + assert abs(arg) == arg + + # special handling to put Abs in denom + assert abs(1/x) == 1/Abs(x) + e = abs(2/x**2) + assert e.is_Mul and e == 2/Abs(x**2) + assert unchanged(Abs, y/x) + assert unchanged(Abs, x/(x + 1)) + assert unchanged(Abs, x*y) + p = Symbol('p', positive=True) + assert abs(x/p) == abs(x)/p + + # coverage + assert unchanged(Abs, Symbol('x', real=True)**y) + # issue 19627 + f = Function('f', positive=True) + assert sqrt(f(x)**2) == f(x) + # issue 21625 + assert unchanged(Abs, S("im(acos(-i + acosh(-g + i)))")) + + +def test_Abs_rewrite(): + x = Symbol('x', real=True) + a = Abs(x).rewrite(Heaviside).expand() + assert a == x*Heaviside(x) - x*Heaviside(-x) + for i in [-2, -1, 0, 1, 2]: + assert a.subs(x, i) == abs(i) + y = Symbol('y') + assert Abs(y).rewrite(Heaviside) == Abs(y) + + x, y = Symbol('x', real=True), Symbol('y') + assert Abs(x).rewrite(Piecewise) == Piecewise((x, x >= 0), (-x, True)) + assert Abs(y).rewrite(Piecewise) == Abs(y) + assert Abs(y).rewrite(sign) == y/sign(y) + + i = Symbol('i', imaginary=True) + assert abs(i).rewrite(Piecewise) == Piecewise((I*i, I*i >= 0), (-I*i, True)) + + + assert Abs(y).rewrite(conjugate) == sqrt(y*conjugate(y)) + assert Abs(i).rewrite(conjugate) == sqrt(-i**2) # == -I*i + + y = Symbol('y', extended_real=True) + assert (Abs(exp(-I*x)-exp(-I*y))**2).rewrite(conjugate) == \ + -exp(I*x)*exp(-I*y) + 2 - exp(-I*x)*exp(I*y) + + +def test_Abs_real(): + # test some properties of abs that only apply + # to real numbers + x = Symbol('x', complex=True) + assert sqrt(x**2) != Abs(x) + assert Abs(x**2) != x**2 + + x = Symbol('x', real=True) + assert sqrt(x**2) == Abs(x) + assert Abs(x**2) == x**2 + + # if the symbol is zero, the following will still apply + nn = Symbol('nn', nonnegative=True, real=True) + np = Symbol('np', nonpositive=True, real=True) + assert Abs(nn) == nn + assert Abs(np) == -np + + +def test_Abs_properties(): + x = Symbol('x') + assert Abs(x).is_real is None + assert Abs(x).is_extended_real is True + assert Abs(x).is_rational is None + assert Abs(x).is_positive is None + assert Abs(x).is_nonnegative is None + assert Abs(x).is_extended_positive is None + assert Abs(x).is_extended_nonnegative is True + + f = Symbol('x', finite=True) + assert Abs(f).is_real is True + assert Abs(f).is_extended_real is True + assert Abs(f).is_rational is None + assert Abs(f).is_positive is None + assert Abs(f).is_nonnegative is True + assert Abs(f).is_extended_positive is None + assert Abs(f).is_extended_nonnegative is True + + z = Symbol('z', complex=True, zero=False) + assert Abs(z).is_real is True # since complex implies finite + assert Abs(z).is_extended_real is True + assert Abs(z).is_rational is None + assert Abs(z).is_positive is True + assert Abs(z).is_extended_positive is True + assert Abs(z).is_zero is False + + p = Symbol('p', positive=True) + assert Abs(p).is_real is True + assert Abs(p).is_extended_real is True + assert Abs(p).is_rational is None + assert Abs(p).is_positive is True + assert Abs(p).is_zero is False + + q = Symbol('q', rational=True) + assert Abs(q).is_real is True + assert Abs(q).is_rational is True + assert Abs(q).is_integer is None + assert Abs(q).is_positive is None + assert Abs(q).is_nonnegative is True + + i = Symbol('i', integer=True) + assert Abs(i).is_real is True + assert Abs(i).is_integer is True + assert Abs(i).is_positive is None + assert Abs(i).is_nonnegative is True + + e = Symbol('n', even=True) + ne = Symbol('ne', real=True, even=False) + assert Abs(e).is_even is True + assert Abs(ne).is_even is False + assert Abs(i).is_even is None + + o = Symbol('n', odd=True) + no = Symbol('no', real=True, odd=False) + assert Abs(o).is_odd is True + assert Abs(no).is_odd is False + assert Abs(i).is_odd is None + + +def test_abs(): + # this tests that abs calls Abs; don't rename to + # test_Abs since that test is already above + a = Symbol('a', positive=True) + assert abs(I*(1 + a)**2) == (1 + a)**2 + + +def test_arg(): + assert arg(0) is nan + assert arg(1) == 0 + assert arg(-1) == pi + assert arg(I) == pi/2 + assert arg(-I) == -pi/2 + assert arg(1 + I) == pi/4 + assert arg(-1 + I) == pi*Rational(3, 4) + assert arg(1 - I) == -pi/4 + assert arg(exp_polar(4*pi*I)) == 4*pi + assert arg(exp_polar(-7*pi*I)) == -7*pi + assert arg(exp_polar(5 - 3*pi*I/4)) == pi*Rational(-3, 4) + + assert arg(exp(I*pi/7)) == pi/7 # issue 17300 + assert arg(exp(16*I)) == 16 - 6*pi + assert arg(exp(13*I*pi/12)) == -11*pi/12 + assert arg(exp(123 - 5*I)) == -5 + 2*pi + assert arg(exp(sin(1 + 3*I))) == -2*pi + cos(1)*sinh(3) + r = Symbol('r', real=True) + assert arg(exp(r - 2*I)) == -2 + + f = Function('f') + assert not arg(f(0) + I*f(1)).atoms(re) + + # check nesting + x = Symbol('x') + assert arg(arg(arg(x))) is not S.NaN + assert arg(arg(arg(arg(x)))) is S.NaN + r = Symbol('r', extended_real=True) + assert arg(arg(r)) is not S.NaN + assert arg(arg(arg(r))) is S.NaN + + p = Function('p', extended_positive=True) + assert arg(p(x)) == 0 + assert arg((3 + I)*p(x)) == arg(3 + I) + + p = Symbol('p', positive=True) + assert arg(p) == 0 + assert arg(p*I) == pi/2 + + n = Symbol('n', negative=True) + assert arg(n) == pi + assert arg(n*I) == -pi/2 + + x = Symbol('x') + assert conjugate(arg(x)) == arg(x) + + e = p + I*p**2 + assert arg(e) == arg(1 + p*I) + # make sure sign doesn't swap + e = -2*p + 4*I*p**2 + assert arg(e) == arg(-1 + 2*p*I) + # make sure sign isn't lost + x = symbols('x', real=True) # could be zero + e = x + I*x + assert arg(e) == arg(x*(1 + I)) + assert arg(e/p) == arg(x*(1 + I)) + e = p*cos(p) + I*log(p)*exp(p) + assert arg(e).args[0] == e + # keep it simple -- let the user do more advanced cancellation + e = (p + 1) + I*(p**2 - 1) + assert arg(e).args[0] == e + + f = Function('f') + e = 2*x*(f(0) - 1) - 2*x*f(0) + assert arg(e) == arg(-2*x) + assert arg(f(0)).func == arg and arg(f(0)).args == (f(0),) + + +def test_arg_rewrite(): + assert arg(1 + I) == atan2(1, 1) + + x = Symbol('x', real=True) + y = Symbol('y', real=True) + assert arg(x + I*y).rewrite(atan2) == atan2(y, x) + + +def test_arg_leading_term_and_series(): + x = Symbol('x') + assert arg(x).as_leading_term(x, cdir = 1) == 0 + assert arg(x).as_leading_term(x, cdir = -1) == pi + raises(PoleError, lambda: arg(x + I).as_leading_term(x, cdir = 1)) + raises(PoleError, lambda: arg(2*x).as_leading_term(x, cdir = I)) + + assert arg(x).nseries(x) == 0 + assert arg(x).nseries(x, n=0) == Order(1) + + +def test_adjoint(): + a = Symbol('a', antihermitian=True) + b = Symbol('b', hermitian=True) + assert adjoint(a) == -a + assert adjoint(I*a) == I*a + assert adjoint(b) == b + assert adjoint(I*b) == -I*b + assert adjoint(a*b) == -b*a + assert adjoint(I*a*b) == I*b*a + + x, y = symbols('x y') + assert adjoint(adjoint(x)) == x + assert adjoint(x + y) == conjugate(x) + conjugate(y) + assert adjoint(x - y) == conjugate(x) - conjugate(y) + assert adjoint(x * y) == conjugate(x) * conjugate(y) + assert adjoint(x / y) == conjugate(x) / conjugate(y) + assert adjoint(-x) == -conjugate(x) + + x, y = symbols('x y', commutative=False) + assert adjoint(adjoint(x)) == x + assert adjoint(x + y) == adjoint(x) + adjoint(y) + assert adjoint(x - y) == adjoint(x) - adjoint(y) + assert adjoint(x * y) == adjoint(y) * adjoint(x) + assert adjoint(x / y) == 1 / adjoint(y) * adjoint(x) + assert adjoint(-x) == -adjoint(x) + + +def test_conjugate(): + a = Symbol('a', real=True) + b = Symbol('b', imaginary=True) + assert conjugate(a) == a + assert conjugate(I*a) == -I*a + assert conjugate(b) == -b + assert conjugate(I*b) == I*b + assert conjugate(a*b) == -a*b + assert conjugate(I*a*b) == I*a*b + + x, y = symbols('x y') + assert conjugate(conjugate(x)) == x + assert conjugate(x).inverse() == conjugate + assert conjugate(x + y) == conjugate(x) + conjugate(y) + assert conjugate(x - y) == conjugate(x) - conjugate(y) + assert conjugate(x * y) == conjugate(x) * conjugate(y) + assert conjugate(x / y) == conjugate(x) / conjugate(y) + assert conjugate(-x) == -conjugate(x) + + a = Symbol('a', algebraic=True) + t = Symbol('t', transcendental=True) + assert re(a).is_algebraic + assert re(x).is_algebraic is None + assert re(t).is_algebraic is False + + +def test_conjugate_transpose(): + x = Symbol('x', commutative=False) + assert conjugate(transpose(x)) == adjoint(x) + assert transpose(conjugate(x)) == adjoint(x) + assert adjoint(transpose(x)) == conjugate(x) + assert transpose(adjoint(x)) == conjugate(x) + assert adjoint(conjugate(x)) == transpose(x) + assert conjugate(adjoint(x)) == transpose(x) + + x = Symbol('x') + assert conjugate(x) == adjoint(x) + assert transpose(x) == x + + +def test_transpose(): + a = Symbol('a', complex=True) + assert transpose(a) == a + assert transpose(I*a) == I*a + + x, y = symbols('x y') + assert transpose(transpose(x)) == x + assert transpose(x + y) == x + y + assert transpose(x - y) == x - y + assert transpose(x * y) == x * y + assert transpose(x / y) == x / y + assert transpose(-x) == -x + + x, y = symbols('x y', commutative=False) + assert transpose(transpose(x)) == x + assert transpose(x + y) == transpose(x) + transpose(y) + assert transpose(x - y) == transpose(x) - transpose(y) + assert transpose(x * y) == transpose(y) * transpose(x) + assert transpose(x / y) == 1 / transpose(y) * transpose(x) + assert transpose(-x) == -transpose(x) + + +@_both_exp_pow +def test_polarify(): + from sympy.functions.elementary.complexes import (polar_lift, polarify) + x = Symbol('x') + z = Symbol('z', polar=True) + f = Function('f') + ES = {} + + assert polarify(-1) == (polar_lift(-1), ES) + assert polarify(1 + I) == (polar_lift(1 + I), ES) + + assert polarify(exp(x), subs=False) == exp(x) + assert polarify(1 + x, subs=False) == 1 + x + assert polarify(f(I) + x, subs=False) == f(polar_lift(I)) + x + + assert polarify(x, lift=True) == polar_lift(x) + assert polarify(z, lift=True) == z + assert polarify(f(x), lift=True) == f(polar_lift(x)) + assert polarify(1 + x, lift=True) == polar_lift(1 + x) + assert polarify(1 + f(x), lift=True) == polar_lift(1 + f(polar_lift(x))) + + newex, subs = polarify(f(x) + z) + assert newex.subs(subs) == f(x) + z + + mu = Symbol("mu") + sigma = Symbol("sigma", positive=True) + + # Make sure polarify(lift=True) doesn't try to lift the integration + # variable + assert polarify( + Integral(sqrt(2)*x*exp(-(-mu + x)**2/(2*sigma**2))/(2*sqrt(pi)*sigma), + (x, -oo, oo)), lift=True) == Integral(sqrt(2)*(sigma*exp_polar(0))**exp_polar(I*pi)* + exp((sigma*exp_polar(0))**(2*exp_polar(I*pi))*exp_polar(I*pi)*polar_lift(-mu + x)** + (2*exp_polar(0))/2)*exp_polar(0)*polar_lift(x)/(2*sqrt(pi)), (x, -oo, oo)) + + +def test_unpolarify(): + from sympy.functions.elementary.complexes import (polar_lift, principal_branch, unpolarify) + from sympy.core.relational import Ne + from sympy.functions.elementary.hyperbolic import tanh + from sympy.functions.special.error_functions import erf + from sympy.functions.special.gamma_functions import (gamma, uppergamma) + from sympy.abc import x + p = exp_polar(7*I) + 1 + u = exp(7*I) + 1 + + assert unpolarify(1) == 1 + assert unpolarify(p) == u + assert unpolarify(p**2) == u**2 + assert unpolarify(p**x) == p**x + assert unpolarify(p*x) == u*x + assert unpolarify(p + x) == u + x + assert unpolarify(sqrt(sin(p))) == sqrt(sin(u)) + + # Test reduction to principal branch 2*pi. + t = principal_branch(x, 2*pi) + assert unpolarify(t) == x + assert unpolarify(sqrt(t)) == sqrt(t) + + # Test exponents_only. + assert unpolarify(p**p, exponents_only=True) == p**u + assert unpolarify(uppergamma(x, p**p)) == uppergamma(x, p**u) + + # Test functions. + assert unpolarify(sin(p)) == sin(u) + assert unpolarify(tanh(p)) == tanh(u) + assert unpolarify(gamma(p)) == gamma(u) + assert unpolarify(erf(p)) == erf(u) + assert unpolarify(uppergamma(x, p)) == uppergamma(x, p) + + assert unpolarify(uppergamma(sin(p), sin(p + exp_polar(0)))) == \ + uppergamma(sin(u), sin(u + 1)) + assert unpolarify(uppergamma(polar_lift(0), 2*exp_polar(0))) == \ + uppergamma(0, 2) + + assert unpolarify(Eq(p, 0)) == Eq(u, 0) + assert unpolarify(Ne(p, 0)) == Ne(u, 0) + assert unpolarify(polar_lift(x) > 0) == (x > 0) + + # Test bools + assert unpolarify(True) is True + + +def test_issue_4035(): + x = Symbol('x') + assert Abs(x).expand(trig=True) == Abs(x) + assert sign(x).expand(trig=True) == sign(x) + assert arg(x).expand(trig=True) == arg(x) + + +def test_issue_3206(): + x = Symbol('x') + assert Abs(Abs(x)) == Abs(x) + + +def test_issue_4754_derivative_conjugate(): + x = Symbol('x', real=True) + y = Symbol('y', imaginary=True) + f = Function('f') + assert (f(x).conjugate()).diff(x) == (f(x).diff(x)).conjugate() + assert (f(y).conjugate()).diff(y) == -(f(y).diff(y)).conjugate() + + +def test_derivatives_issue_4757(): + x = Symbol('x', real=True) + y = Symbol('y', imaginary=True) + f = Function('f') + assert re(f(x)).diff(x) == re(f(x).diff(x)) + assert im(f(x)).diff(x) == im(f(x).diff(x)) + assert re(f(y)).diff(y) == -I*im(f(y).diff(y)) + assert im(f(y)).diff(y) == -I*re(f(y).diff(y)) + assert Abs(f(x)).diff(x).subs(f(x), 1 + I*x).doit() == x/sqrt(1 + x**2) + assert arg(f(x)).diff(x).subs(f(x), 1 + I*x**2).doit() == 2*x/(1 + x**4) + assert Abs(f(y)).diff(y).subs(f(y), 1 + y).doit() == -y/sqrt(1 - y**2) + assert arg(f(y)).diff(y).subs(f(y), I + y**2).doit() == 2*y/(1 + y**4) + + +def test_issue_11413(): + from sympy.simplify.simplify import simplify + v0 = Symbol('v0') + v1 = Symbol('v1') + v2 = Symbol('v2') + V = Matrix([[v0],[v1],[v2]]) + U = V.normalized() + assert U == Matrix([ + [v0/sqrt(Abs(v0)**2 + Abs(v1)**2 + Abs(v2)**2)], + [v1/sqrt(Abs(v0)**2 + Abs(v1)**2 + Abs(v2)**2)], + [v2/sqrt(Abs(v0)**2 + Abs(v1)**2 + Abs(v2)**2)]]) + U.norm = sqrt(v0**2/(v0**2 + v1**2 + v2**2) + v1**2/(v0**2 + v1**2 + v2**2) + v2**2/(v0**2 + v1**2 + v2**2)) + assert simplify(U.norm) == 1 + + +def test_periodic_argument(): + from sympy.functions.elementary.complexes import (periodic_argument, polar_lift, principal_branch, unbranched_argument) + x = Symbol('x') + p = Symbol('p', positive=True) + + assert unbranched_argument(2 + I) == periodic_argument(2 + I, oo) + assert unbranched_argument(1 + x) == periodic_argument(1 + x, oo) + assert N_equals(unbranched_argument((1 + I)**2), pi/2) + assert N_equals(unbranched_argument((1 - I)**2), -pi/2) + assert N_equals(periodic_argument((1 + I)**2, 3*pi), pi/2) + assert N_equals(periodic_argument((1 - I)**2, 3*pi), -pi/2) + + assert unbranched_argument(principal_branch(x, pi)) == \ + periodic_argument(x, pi) + + assert unbranched_argument(polar_lift(2 + I)) == unbranched_argument(2 + I) + assert periodic_argument(polar_lift(2 + I), 2*pi) == \ + periodic_argument(2 + I, 2*pi) + assert periodic_argument(polar_lift(2 + I), 3*pi) == \ + periodic_argument(2 + I, 3*pi) + assert periodic_argument(polar_lift(2 + I), pi) == \ + periodic_argument(polar_lift(2 + I), pi) + + assert unbranched_argument(polar_lift(1 + I)) == pi/4 + assert periodic_argument(2*p, p) == periodic_argument(p, p) + assert periodic_argument(pi*p, p) == periodic_argument(p, p) + + assert Abs(polar_lift(1 + I)) == Abs(1 + I) + + +@XFAIL +def test_principal_branch_fail(): + # TODO XXX why does abs(x)._eval_evalf() not fall back to global evalf? + from sympy.functions.elementary.complexes import principal_branch + assert N_equals(principal_branch((1 + I)**2, pi/2), 0) + + +def test_principal_branch(): + from sympy.functions.elementary.complexes import (polar_lift, principal_branch) + p = Symbol('p', positive=True) + x = Symbol('x') + neg = Symbol('x', negative=True) + + assert principal_branch(polar_lift(x), p) == principal_branch(x, p) + assert principal_branch(polar_lift(2 + I), p) == principal_branch(2 + I, p) + assert principal_branch(2*x, p) == 2*principal_branch(x, p) + assert principal_branch(1, pi) == exp_polar(0) + assert principal_branch(-1, 2*pi) == exp_polar(I*pi) + assert principal_branch(-1, pi) == exp_polar(0) + assert principal_branch(exp_polar(3*pi*I)*x, 2*pi) == \ + principal_branch(exp_polar(I*pi)*x, 2*pi) + assert principal_branch(neg*exp_polar(pi*I), 2*pi) == neg*exp_polar(-I*pi) + # related to issue #14692 + assert principal_branch(exp_polar(-I*pi/2)/polar_lift(neg), 2*pi) == \ + exp_polar(-I*pi/2)/neg + + assert N_equals(principal_branch((1 + I)**2, 2*pi), 2*I) + assert N_equals(principal_branch((1 + I)**2, 3*pi), 2*I) + assert N_equals(principal_branch((1 + I)**2, 1*pi), 2*I) + + # test argument sanitization + assert principal_branch(x, I).func is principal_branch + assert principal_branch(x, -4).func is principal_branch + assert principal_branch(x, -oo).func is principal_branch + assert principal_branch(x, zoo).func is principal_branch + + +@XFAIL +def test_issue_6167_6151(): + n = pi**1000 + i = int(n) + assert sign(n - i) == 1 + assert abs(n - i) == n - i + x = Symbol('x') + eps = pi**-1500 + big = pi**1000 + one = cos(x)**2 + sin(x)**2 + e = big*one - big + eps + from sympy.simplify.simplify import simplify + assert sign(simplify(e)) == 1 + for xi in (111, 11, 1, Rational(1, 10)): + assert sign(e.subs(x, xi)) == 1 + + +def test_issue_14216(): + from sympy.functions.elementary.complexes import unpolarify + A = MatrixSymbol("A", 2, 2) + assert unpolarify(A[0, 0]) == A[0, 0] + assert unpolarify(A[0, 0]*A[1, 0]) == A[0, 0]*A[1, 0] + + +def test_issue_14238(): + # doesn't cause recursion error + r = Symbol('r', real=True) + assert Abs(r + Piecewise((0, r > 0), (1 - r, True))) + + +def test_issue_22189(): + x = Symbol('x') + for a in (sqrt(7 - 2*x) - 2, 1 - x): + assert Abs(a) - Abs(-a) == 0, a + + +def test_zero_assumptions(): + nr = Symbol('nonreal', real=False, finite=True) + ni = Symbol('nonimaginary', imaginary=False) + # imaginary implies not zero + nzni = Symbol('nonzerononimaginary', zero=False, imaginary=False) + + assert re(nr).is_zero is None + assert im(nr).is_zero is False + + assert re(ni).is_zero is None + assert im(ni).is_zero is None + + assert re(nzni).is_zero is False + assert im(nzni).is_zero is None + + +@_both_exp_pow +def test_issue_15893(): + f = Function('f', real=True) + x = Symbol('x', real=True) + eq = Derivative(Abs(f(x)), f(x)) + assert eq.doit() == sign(f(x)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_exponential.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_exponential.py new file mode 100644 index 0000000000000000000000000000000000000000..ee8c311d01e98d7fd6831ad754e854fae409aa0c --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_exponential.py @@ -0,0 +1,810 @@ +from sympy.assumptions.refine import refine +from sympy.calculus.accumulationbounds import AccumBounds +from sympy.concrete.products import Product +from sympy.concrete.summations import Sum +from sympy.core.function import expand_log +from sympy.core.numbers import (E, Float, I, Rational, nan, oo, pi, zoo) +from sympy.core.power import Pow +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.complexes import (adjoint, conjugate, re, sign, transpose) +from sympy.functions.elementary.exponential import (LambertW, exp, exp_polar, log) +from sympy.functions.elementary.hyperbolic import (cosh, sinh, tanh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (cos, sin, tan) +from sympy.matrices.expressions.matexpr import MatrixSymbol +from sympy.polys.polytools import gcd +from sympy.series.order import O +from sympy.simplify.simplify import simplify +from sympy.core.parameters import global_parameters +from sympy.functions.elementary.exponential import match_real_imag +from sympy.abc import x, y, z +from sympy.core.expr import unchanged +from sympy.core.function import ArgumentIndexError +from sympy.testing.pytest import raises, XFAIL, _both_exp_pow + + +@_both_exp_pow +def test_exp_values(): + if global_parameters.exp_is_pow: + assert type(exp(x)) is Pow + else: + assert type(exp(x)) is exp + + k = Symbol('k', integer=True) + + assert exp(nan) is nan + + assert exp(oo) is oo + assert exp(-oo) == 0 + + assert exp(0) == 1 + assert exp(1) == E + assert exp(-1 + x).as_base_exp() == (S.Exp1, x - 1) + assert exp(1 + x).as_base_exp() == (S.Exp1, x + 1) + + assert exp(pi*I/2) == I + assert exp(pi*I) == -1 + assert exp(pi*I*Rational(3, 2)) == -I + assert exp(2*pi*I) == 1 + + assert refine(exp(pi*I*2*k)) == 1 + assert refine(exp(pi*I*2*(k + S.Half))) == -1 + assert refine(exp(pi*I*2*(k + Rational(1, 4)))) == I + assert refine(exp(pi*I*2*(k + Rational(3, 4)))) == -I + + assert exp(log(x)) == x + assert exp(2*log(x)) == x**2 + assert exp(pi*log(x)) == x**pi + + assert exp(17*log(x) + E*log(y)) == x**17 * y**E + + assert exp(x*log(x)) != x**x + assert exp(sin(x)*log(x)) != x + + assert exp(3*log(x) + oo*x) == exp(oo*x) * x**3 + assert exp(4*log(x)*log(y) + 3*log(x)) == x**3 * exp(4*log(x)*log(y)) + + assert exp(-oo, evaluate=False).is_finite is True + assert exp(oo, evaluate=False).is_finite is False + + +@_both_exp_pow +def test_exp_period(): + assert exp(I*pi*Rational(9, 4)) == exp(I*pi/4) + assert exp(I*pi*Rational(46, 18)) == exp(I*pi*Rational(5, 9)) + assert exp(I*pi*Rational(25, 7)) == exp(I*pi*Rational(-3, 7)) + assert exp(I*pi*Rational(-19, 3)) == exp(-I*pi/3) + assert exp(I*pi*Rational(37, 8)) - exp(I*pi*Rational(-11, 8)) == 0 + assert exp(I*pi*Rational(-5, 3)) / exp(I*pi*Rational(11, 5)) * exp(I*pi*Rational(148, 15)) == 1 + + assert exp(2 - I*pi*Rational(17, 5)) == exp(2 + I*pi*Rational(3, 5)) + assert exp(log(3) + I*pi*Rational(29, 9)) == 3 * exp(I*pi*Rational(-7, 9)) + + n = Symbol('n', integer=True) + e = Symbol('e', even=True) + assert exp(e*I*pi) == 1 + assert exp((e + 1)*I*pi) == -1 + assert exp((1 + 4*n)*I*pi/2) == I + assert exp((-1 + 4*n)*I*pi/2) == -I + + +@_both_exp_pow +def test_exp_log(): + x = Symbol("x", real=True) + assert log(exp(x)) == x + assert exp(log(x)) == x + + if not global_parameters.exp_is_pow: + assert log(x).inverse() == exp + assert exp(x).inverse() == log + + y = Symbol("y", polar=True) + assert log(exp_polar(z)) == z + assert exp(log(y)) == y + + +@_both_exp_pow +def test_exp_expand(): + e = exp(log(Rational(2))*(1 + x) - log(Rational(2))*x) + assert e.expand() == 2 + assert exp(x + y) != exp(x)*exp(y) + assert exp(x + y).expand() == exp(x)*exp(y) + + +@_both_exp_pow +def test_exp__as_base_exp(): + assert exp(x).as_base_exp() == (E, x) + assert exp(2*x).as_base_exp() == (E, 2*x) + assert exp(x*y).as_base_exp() == (E, x*y) + assert exp(-x).as_base_exp() == (E, -x) + + # Pow( *expr.as_base_exp() ) == expr invariant should hold + assert E**x == exp(x) + assert E**(2*x) == exp(2*x) + assert E**(x*y) == exp(x*y) + + assert exp(x).base is S.Exp1 + assert exp(x).exp == x + + +@_both_exp_pow +def test_exp_infinity(): + assert exp(I*y) != nan + assert refine(exp(I*oo)) is nan + assert refine(exp(-I*oo)) is nan + assert exp(y*I*oo) != nan + assert exp(zoo) is nan + x = Symbol('x', extended_real=True, finite=False) + assert exp(x).is_complex is None + + +@_both_exp_pow +def test_exp_subs(): + x = Symbol('x') + e = (exp(3*log(x), evaluate=False)) # evaluates to x**3 + assert e.subs(x**3, y**3) == e + assert e.subs(x**2, 5) == e + assert (x**3).subs(x**2, y) != y**Rational(3, 2) + assert exp(exp(x) + exp(x**2)).subs(exp(exp(x)), y) == y * exp(exp(x**2)) + assert exp(x).subs(E, y) == y**x + x = symbols('x', real=True) + assert exp(5*x).subs(exp(7*x), y) == y**Rational(5, 7) + assert exp(2*x + 7).subs(exp(3*x), y) == y**Rational(2, 3) * exp(7) + x = symbols('x', positive=True) + assert exp(3*log(x)).subs(x**2, y) == y**Rational(3, 2) + # differentiate between E and exp + assert exp(exp(x + E)).subs(exp, 3) == 3**(3**(x + E)) + assert exp(exp(x + E)).subs(exp, sin) == sin(sin(x + E)) + assert exp(exp(x + E)).subs(E, 3) == 3**(3**(x + 3)) + assert exp(3).subs(E, sin) == sin(3) + + +def test_exp_adjoint(): + x = Symbol('x', commutative=False) + assert adjoint(exp(x)) == exp(adjoint(x)) + + +def test_exp_conjugate(): + assert conjugate(exp(x)) == exp(conjugate(x)) + + +@_both_exp_pow +def test_exp_transpose(): + assert transpose(exp(x)) == exp(transpose(x)) + + +@_both_exp_pow +def test_exp_rewrite(): + assert exp(x).rewrite(sin) == sinh(x) + cosh(x) + assert exp(x*I).rewrite(cos) == cos(x) + I*sin(x) + assert exp(1).rewrite(cos) == sinh(1) + cosh(1) + assert exp(1).rewrite(sin) == sinh(1) + cosh(1) + assert exp(1).rewrite(sin) == sinh(1) + cosh(1) + assert exp(x).rewrite(tanh) == (1 + tanh(x/2))/(1 - tanh(x/2)) + assert exp(pi*I/4).rewrite(sqrt) == sqrt(2)/2 + sqrt(2)*I/2 + assert exp(pi*I/3).rewrite(sqrt) == S.Half + sqrt(3)*I/2 + if not global_parameters.exp_is_pow: + assert exp(x*log(y)).rewrite(Pow) == y**x + assert exp(log(x)*log(y)).rewrite(Pow) in [x**log(y), y**log(x)] + assert exp(log(log(x))*y).rewrite(Pow) == log(x)**y + + n = Symbol('n', integer=True) + + assert Sum((exp(pi*I/2)/2)**n, (n, 0, oo)).rewrite(sqrt).doit() == Rational(4, 5) + I*2/5 + assert Sum((exp(pi*I/4)/2)**n, (n, 0, oo)).rewrite(sqrt).doit() == 1/(1 - sqrt(2)*(1 + I)/4) + assert (Sum((exp(pi*I/3)/2)**n, (n, 0, oo)).rewrite(sqrt).doit().cancel() + == 4*I/(sqrt(3) + 3*I)) + + +@_both_exp_pow +def test_exp_leading_term(): + assert exp(x).as_leading_term(x) == 1 + assert exp(2 + x).as_leading_term(x) == exp(2) + assert exp((2*x + 3) / (x+1)).as_leading_term(x) == exp(3) + + # The following tests are commented, since now SymPy returns the + # original function when the leading term in the series expansion does + # not exist. + # raises(NotImplementedError, lambda: exp(1/x).as_leading_term(x)) + # raises(NotImplementedError, lambda: exp((x + 1) / x**2).as_leading_term(x)) + # raises(NotImplementedError, lambda: exp(x + 1/x).as_leading_term(x)) + + +@_both_exp_pow +def test_exp_taylor_term(): + x = symbols('x') + assert exp(x).taylor_term(1, x) == x + assert exp(x).taylor_term(3, x) == x**3/6 + assert exp(x).taylor_term(4, x) == x**4/24 + assert exp(x).taylor_term(-1, x) is S.Zero + + +def test_exp_MatrixSymbol(): + A = MatrixSymbol("A", 2, 2) + assert exp(A).has(exp) + + +def test_exp_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: exp(x).fdiff(2)) + + +def test_log_values(): + assert log(nan) is nan + + assert log(oo) is oo + assert log(-oo) is oo + + assert log(zoo) is zoo + assert log(-zoo) is zoo + + assert log(0) is zoo + + assert log(1) == 0 + assert log(-1) == I*pi + + assert log(E) == 1 + assert log(-E).expand() == 1 + I*pi + + assert unchanged(log, pi) + assert log(-pi).expand() == log(pi) + I*pi + + assert unchanged(log, 17) + assert log(-17) == log(17) + I*pi + + assert log(I) == I*pi/2 + assert log(-I) == -I*pi/2 + + assert log(17*I) == I*pi/2 + log(17) + assert log(-17*I).expand() == -I*pi/2 + log(17) + + assert log(oo*I) is oo + assert log(-oo*I) is oo + assert log(0, 2) is zoo + assert log(0, 5) is zoo + + assert exp(-log(3))**(-1) == 3 + + assert log(S.Half) == -log(2) + assert log(2*3).func is log + assert log(2*3**2).func is log + + +def test_match_real_imag(): + x, y = symbols('x,y', real=True) + i = Symbol('i', imaginary=True) + assert match_real_imag(S.One) == (1, 0) + assert match_real_imag(I) == (0, 1) + assert match_real_imag(3 - 5*I) == (3, -5) + assert match_real_imag(-sqrt(3) + S.Half*I) == (-sqrt(3), S.Half) + assert match_real_imag(x + y*I) == (x, y) + assert match_real_imag(x*I + y*I) == (0, x + y) + assert match_real_imag((x + y)*I) == (0, x + y) + assert match_real_imag(Rational(-2, 3)*i*I) == (None, None) + assert match_real_imag(1 - 2*i) == (None, None) + assert match_real_imag(sqrt(2)*(3 - 5*I)) == (None, None) + + +def test_log_exact(): + # check for pi/2, pi/3, pi/4, pi/6, pi/8, pi/12; pi/5, pi/10: + for n in range(-23, 24): + if gcd(n, 24) != 1: + assert log(exp(n*I*pi/24).rewrite(sqrt)) == n*I*pi/24 + for n in range(-9, 10): + assert log(exp(n*I*pi/10).rewrite(sqrt)) == n*I*pi/10 + + assert log(S.Half - I*sqrt(3)/2) == -I*pi/3 + assert log(Rational(-1, 2) + I*sqrt(3)/2) == I*pi*Rational(2, 3) + assert log(-sqrt(2)/2 - I*sqrt(2)/2) == -I*pi*Rational(3, 4) + assert log(-sqrt(3)/2 - I*S.Half) == -I*pi*Rational(5, 6) + + assert log(Rational(-1, 4) + sqrt(5)/4 - I*sqrt(sqrt(5)/8 + Rational(5, 8))) == -I*pi*Rational(2, 5) + assert log(sqrt(Rational(5, 8) - sqrt(5)/8) + I*(Rational(1, 4) + sqrt(5)/4)) == I*pi*Rational(3, 10) + assert log(-sqrt(sqrt(2)/4 + S.Half) + I*sqrt(S.Half - sqrt(2)/4)) == I*pi*Rational(7, 8) + assert log(-sqrt(6)/4 - sqrt(2)/4 + I*(-sqrt(6)/4 + sqrt(2)/4)) == -I*pi*Rational(11, 12) + + assert log(-1 + I*sqrt(3)) == log(2) + I*pi*Rational(2, 3) + assert log(5 + 5*I) == log(5*sqrt(2)) + I*pi/4 + assert log(sqrt(-12)) == log(2*sqrt(3)) + I*pi/2 + assert log(-sqrt(6) + sqrt(2) - I*sqrt(6) - I*sqrt(2)) == log(4) - I*pi*Rational(7, 12) + assert log(-sqrt(6-3*sqrt(2)) - I*sqrt(6+3*sqrt(2))) == log(2*sqrt(3)) - I*pi*Rational(5, 8) + assert log(1 + I*sqrt(2-sqrt(2))/sqrt(2+sqrt(2))) == log(2/sqrt(sqrt(2) + 2)) + I*pi/8 + assert log(cos(pi*Rational(7, 12)) + I*sin(pi*Rational(7, 12))) == I*pi*Rational(7, 12) + assert log(cos(pi*Rational(6, 5)) + I*sin(pi*Rational(6, 5))) == I*pi*Rational(-4, 5) + + assert log(5*(1 + I)/sqrt(2)) == log(5) + I*pi/4 + assert log(sqrt(2)*(-sqrt(3) + 1 - sqrt(3)*I - I)) == log(4) - I*pi*Rational(7, 12) + assert log(-sqrt(2)*(1 - I*sqrt(3))) == log(2*sqrt(2)) + I*pi*Rational(2, 3) + assert log(sqrt(3)*I*(-sqrt(6 - 3*sqrt(2)) - I*sqrt(3*sqrt(2) + 6))) == log(6) - I*pi/8 + + zero = (1 + sqrt(2))**2 - 3 - 2*sqrt(2) + assert log(zero - I*sqrt(3)) == log(sqrt(3)) - I*pi/2 + assert unchanged(log, zero + I*zero) or log(zero + zero*I) is zoo + + # bail quickly if no obvious simplification is possible: + assert unchanged(log, (sqrt(2)-1/sqrt(sqrt(3)+I))**1000) + # beware of non-real coefficients + assert unchanged(log, sqrt(2-sqrt(5))*(1 + I)) + + +def test_log_base(): + assert log(1, 2) == 0 + assert log(2, 2) == 1 + assert log(3, 2) == log(3)/log(2) + assert log(6, 2) == 1 + log(3)/log(2) + assert log(6, 3) == 1 + log(2)/log(3) + assert log(2**3, 2) == 3 + assert log(3**3, 3) == 3 + assert log(5, 1) is zoo + assert log(1, 1) is nan + assert log(Rational(2, 3), 10) == log(Rational(2, 3))/log(10) + assert log(Rational(2, 3), Rational(1, 3)) == -log(2)/log(3) + 1 + assert log(Rational(2, 3), Rational(2, 5)) == \ + log(Rational(2, 3))/log(Rational(2, 5)) + # issue 17148 + assert log(Rational(8, 3), 2) == -log(3)/log(2) + 3 + + +def test_log_symbolic(): + assert log(x, exp(1)) == log(x) + assert log(exp(x)) != x + + assert log(x, exp(1)) == log(x) + assert log(x*y) != log(x) + log(y) + assert log(x/y).expand() != log(x) - log(y) + assert log(x/y).expand(force=True) == log(x) - log(y) + assert log(x**y).expand() != y*log(x) + assert log(x**y).expand(force=True) == y*log(x) + + assert log(x, 2) == log(x)/log(2) + assert log(E, 2) == 1/log(2) + + p, q = symbols('p,q', positive=True) + r = Symbol('r', real=True) + + assert log(p**2) != 2*log(p) + assert log(p**2).expand() == 2*log(p) + assert log(x**2).expand() != 2*log(x) + assert log(p**q) != q*log(p) + assert log(exp(p)) == p + assert log(p*q) != log(p) + log(q) + assert log(p*q).expand() == log(p) + log(q) + + assert log(-sqrt(3)) == log(sqrt(3)) + I*pi + assert log(-exp(p)) != p + I*pi + assert log(-exp(x)).expand() != x + I*pi + assert log(-exp(r)).expand() == r + I*pi + + assert log(x**y) != y*log(x) + + assert (log(x**-5)**-1).expand() != -1/log(x)/5 + assert (log(p**-5)**-1).expand() == -1/log(p)/5 + assert log(-x).func is log and log(-x).args[0] == -x + assert log(-p).func is log and log(-p).args[0] == -p + + +def test_log_exp(): + assert log(exp(4*I*pi)) == 0 # exp evaluates + assert log(exp(-5*I*pi)) == I*pi # exp evaluates + assert log(exp(I*pi*Rational(19, 4))) == I*pi*Rational(3, 4) + assert log(exp(I*pi*Rational(25, 7))) == I*pi*Rational(-3, 7) + assert log(exp(-5*I)) == -5*I + 2*I*pi + + +@_both_exp_pow +def test_exp_assumptions(): + r = Symbol('r', real=True) + i = Symbol('i', imaginary=True) + for e in exp, exp_polar: + assert e(x).is_real is None + assert e(x).is_imaginary is None + assert e(i).is_real is None + assert e(i).is_imaginary is None + assert e(r).is_real is True + assert e(r).is_imaginary is False + assert e(re(x)).is_extended_real is True + assert e(re(x)).is_imaginary is False + + assert Pow(E, I*pi, evaluate=False).is_imaginary == False + assert Pow(E, 2*I*pi, evaluate=False).is_imaginary == False + assert Pow(E, I*pi/2, evaluate=False).is_imaginary == True + assert Pow(E, I*pi/3, evaluate=False).is_imaginary is None + + assert exp(0, evaluate=False).is_algebraic + + a = Symbol('a', algebraic=True) + an = Symbol('an', algebraic=True, nonzero=True) + r = Symbol('r', rational=True) + rn = Symbol('rn', rational=True, nonzero=True) + assert exp(a).is_algebraic is None + assert exp(an).is_algebraic is False + assert exp(pi*r).is_algebraic is None + assert exp(pi*rn).is_algebraic is False + + assert exp(0, evaluate=False).is_algebraic is True + assert exp(I*pi/3, evaluate=False).is_algebraic is True + assert exp(I*pi*r, evaluate=False).is_algebraic is True + + +@_both_exp_pow +def test_exp_AccumBounds(): + assert exp(AccumBounds(1, 2)) == AccumBounds(E, E**2) + + +def test_log_assumptions(): + p = symbols('p', positive=True) + n = symbols('n', negative=True) + z = symbols('z', zero=True) + x = symbols('x', infinite=True, extended_positive=True) + + assert log(z).is_positive is False + assert log(x).is_extended_positive is True + assert log(2) > 0 + assert log(1, evaluate=False).is_zero + assert log(1 + z).is_zero + assert log(p).is_zero is None + assert log(n).is_zero is False + assert log(0.5).is_negative is True + assert log(exp(p) + 1).is_positive + + assert log(1, evaluate=False).is_algebraic + assert log(42, evaluate=False).is_algebraic is False + + assert log(1 + z).is_rational + + +def test_log_hashing(): + assert x != log(log(x)) + assert hash(x) != hash(log(log(x))) + assert log(x) != log(log(log(x))) + + e = 1/log(log(x) + log(log(x))) + assert e.base.func is log + e = 1/log(log(x) + log(log(log(x)))) + assert e.base.func is log + + e = log(log(x)) + assert e.func is log + assert x.func is not log + assert hash(log(log(x))) != hash(x) + assert e != x + + +def test_log_sign(): + assert sign(log(2)) == 1 + + +def test_log_expand_complex(): + assert log(1 + I).expand(complex=True) == log(2)/2 + I*pi/4 + assert log(1 - sqrt(2)).expand(complex=True) == log(sqrt(2) - 1) + I*pi + + +def test_log_apply_evalf(): + value = (log(3)/log(2) - 1).evalf() + assert value.epsilon_eq(Float("0.58496250072115618145373")) + + +def test_log_leading_term(): + p = Symbol('p') + + # Test for STEP 3 + assert log(1 + x + x**2).as_leading_term(x, cdir=1) == x + # Test for STEP 4 + assert log(2*x).as_leading_term(x, cdir=1) == log(x) + log(2) + assert log(2*x).as_leading_term(x, cdir=-1) == log(x) + log(2) + assert log(-2*x).as_leading_term(x, cdir=1, logx=p) == p + log(2) + I*pi + assert log(-2*x).as_leading_term(x, cdir=-1, logx=p) == p + log(2) - I*pi + # Test for STEP 5 + assert log(-2*x + (3 - I)*x**2).as_leading_term(x, cdir=1) == log(x) + log(2) - I*pi + assert log(-2*x + (3 - I)*x**2).as_leading_term(x, cdir=-1) == log(x) + log(2) - I*pi + assert log(2*x + (3 - I)*x**2).as_leading_term(x, cdir=1) == log(x) + log(2) + assert log(2*x + (3 - I)*x**2).as_leading_term(x, cdir=-1) == log(x) + log(2) - 2*I*pi + assert log(-1 + x - I*x**2 + I*x**3).as_leading_term(x, cdir=1) == -I*pi + assert log(-1 + x - I*x**2 + I*x**3).as_leading_term(x, cdir=-1) == -I*pi + assert log(-1/(1 - x)).as_leading_term(x, cdir=1) == I*pi + assert log(-1/(1 - x)).as_leading_term(x, cdir=-1) == I*pi + + +def test_log_nseries(): + p = Symbol('p') + assert log(1/x)._eval_nseries(x, 4, logx=-p, cdir=1) == p + assert log(1/x)._eval_nseries(x, 4, logx=-p, cdir=-1) == p + 2*I*pi + assert log(x - 1)._eval_nseries(x, 4, None, I) == I*pi - x - x**2/2 - x**3/3 + O(x**4) + assert log(x - 1)._eval_nseries(x, 4, None, -I) == -I*pi - x - x**2/2 - x**3/3 + O(x**4) + assert log(I*x + I*x**3 - 1)._eval_nseries(x, 3, None, 1) == I*pi - I*x + x**2/2 + O(x**3) + assert log(I*x + I*x**3 - 1)._eval_nseries(x, 3, None, -1) == -I*pi - I*x + x**2/2 + O(x**3) + assert log(I*x**2 + I*x**3 - 1)._eval_nseries(x, 3, None, 1) == I*pi - I*x**2 + O(x**3) + assert log(I*x**2 + I*x**3 - 1)._eval_nseries(x, 3, None, -1) == I*pi - I*x**2 + O(x**3) + assert log(2*x + (3 - I)*x**2)._eval_nseries(x, 3, None, 1) == log(2) + log(x) + \ + x*(S(3)/2 - I/2) + x**2*(-1 + 3*I/4) + O(x**3) + assert log(2*x + (3 - I)*x**2)._eval_nseries(x, 3, None, -1) == -2*I*pi + log(2) + \ + log(x) - x*(-S(3)/2 + I/2) + x**2*(-1 + 3*I/4) + O(x**3) + assert log(-2*x + (3 - I)*x**2)._eval_nseries(x, 3, None, 1) == -I*pi + log(2) + log(x) + \ + x*(-S(3)/2 + I/2) + x**2*(-1 + 3*I/4) + O(x**3) + assert log(-2*x + (3 - I)*x**2)._eval_nseries(x, 3, None, -1) == -I*pi + log(2) + log(x) - \ + x*(S(3)/2 - I/2) + x**2*(-1 + 3*I/4) + O(x**3) + assert log(sqrt(-I*x**2 - 3)*sqrt(-I*x**2 - 1) - 2)._eval_nseries(x, 3, None, 1) == -I*pi + \ + log(sqrt(3) + 2) + 2*sqrt(3)*I*x**2/(3*sqrt(3) + 6) + O(x**3) + assert log(-1/(1 - x))._eval_nseries(x, 3, None, 1) == I*pi + x + x**2/2 + O(x**3) + assert log(-1/(1 - x))._eval_nseries(x, 3, None, -1) == I*pi + x + x**2/2 + O(x**3) + + +def test_log_series(): + # Note Series at infinities other than oo/-oo were introduced as a part of + # pull request 23798. Refer https://github.com/sympy/sympy/pull/23798 for + # more information. + expr1 = log(1 + x) + expr2 = log(x + sqrt(x**2 + 1)) + + assert expr1.series(x, x0=I*oo, n=4) == 1/(3*x**3) - 1/(2*x**2) + 1/x + \ + I*pi/2 - log(I/x) + O(x**(-4), (x, oo*I)) + assert expr1.series(x, x0=-I*oo, n=4) == 1/(3*x**3) - 1/(2*x**2) + 1/x - \ + I*pi/2 - log(-I/x) + O(x**(-4), (x, -oo*I)) + assert expr2.series(x, x0=I*oo, n=4) == 1/(4*x**2) + I*pi/2 + log(2) - \ + log(I/x) + O(x**(-4), (x, oo*I)) + assert expr2.series(x, x0=-I*oo, n=4) == -1/(4*x**2) - I*pi/2 - log(2) + \ + log(-I/x) + O(x**(-4), (x, -oo*I)) + + +def test_log_expand(): + w = Symbol("w", positive=True) + e = log(w**(log(5)/log(3))) + assert e.expand() == log(5)/log(3) * log(w) + x, y, z = symbols('x,y,z', positive=True) + assert log(x*(y + z)).expand(mul=False) == log(x) + log(y + z) + assert log(log(x**2)*log(y*z)).expand() in [log(2*log(x)*log(y) + + 2*log(x)*log(z)), log(log(x)*log(z) + log(y)*log(x)) + log(2), + log((log(y) + log(z))*log(x)) + log(2)] + assert log(x**log(x**2)).expand(deep=False) == log(x)*log(x**2) + assert log(x**log(x**2)).expand() == 2*log(x)**2 + x, y = symbols('x,y') + assert log(x*y).expand(force=True) == log(x) + log(y) + assert log(x**y).expand(force=True) == y*log(x) + assert log(exp(x)).expand(force=True) == x + + # there's generally no need to expand out logs since this requires + # factoring and if simplification is sought, it's cheaper to put + # logs together than it is to take them apart. + assert log(2*3**2).expand() != 2*log(3) + log(2) + + +@XFAIL +def test_log_expand_fail(): + x, y, z = symbols('x,y,z', positive=True) + assert (log(x*(y + z))*(x + y)).expand(mul=True, log=True) == y*log( + x) + y*log(y + z) + z*log(x) + z*log(y + z) + + +def test_log_simplify(): + x = Symbol("x", positive=True) + assert log(x**2).expand() == 2*log(x) + assert expand_log(log(x**(2 + log(2)))) == (2 + log(2))*log(x) + + z = Symbol('z') + assert log(sqrt(z)).expand() == log(z)/2 + assert expand_log(log(z**(log(2) - 1))) == (log(2) - 1)*log(z) + assert log(z**(-1)).expand() != -log(z) + assert log(z**(x/(x+1))).expand() == x*log(z)/(x + 1) + + +def test_log_AccumBounds(): + assert log(AccumBounds(1, E)) == AccumBounds(0, 1) + assert log(AccumBounds(0, E)) == AccumBounds(-oo, 1) + assert log(AccumBounds(-1, E)) == S.NaN + assert log(AccumBounds(0, oo)) == AccumBounds(-oo, oo) + assert log(AccumBounds(-oo, 0)) == S.NaN + assert log(AccumBounds(-oo, oo)) == S.NaN + + +@_both_exp_pow +def test_lambertw(): + k = Symbol('k') + + assert LambertW(x, 0) == LambertW(x) + assert LambertW(x, 0, evaluate=False) != LambertW(x) + assert LambertW(0) == 0 + assert LambertW(E) == 1 + assert LambertW(-1/E) == -1 + assert LambertW(-log(2)/2) == -log(2) + assert LambertW(oo) is oo + assert LambertW(0, 1) is -oo + assert LambertW(0, 42) is -oo + assert LambertW(-pi/2, -1) == -I*pi/2 + assert LambertW(-1/E, -1) == -1 + assert LambertW(-2*exp(-2), -1) == -2 + assert LambertW(2*log(2)) == log(2) + assert LambertW(-pi/2) == I*pi/2 + assert LambertW(exp(1 + E)) == E + + assert LambertW(x**2).diff(x) == 2*LambertW(x**2)/x/(1 + LambertW(x**2)) + assert LambertW(x, k).diff(x) == LambertW(x, k)/x/(1 + LambertW(x, k)) + + assert LambertW(sqrt(2)).evalf(30).epsilon_eq( + Float("0.701338383413663009202120278965", 30), 1e-29) + assert re(LambertW(2, -1)).evalf().epsilon_eq(Float("-0.834310366631110")) + + assert LambertW(-1).is_real is False # issue 5215 + assert LambertW(2, evaluate=False).is_real + p = Symbol('p', positive=True) + assert LambertW(p, evaluate=False).is_real + assert LambertW(p - 1, evaluate=False).is_real is None + assert LambertW(-p - 2/S.Exp1, evaluate=False).is_real is False + assert LambertW(S.Half, -1, evaluate=False).is_real is False + assert LambertW(Rational(-1, 10), -1, evaluate=False).is_real + assert LambertW(-10, -1, evaluate=False).is_real is False + assert LambertW(-2, 2, evaluate=False).is_real is False + + assert LambertW(0, evaluate=False).is_algebraic + na = Symbol('na', nonzero=True, algebraic=True) + assert LambertW(na).is_algebraic is False + assert LambertW(p).is_zero is False + n = Symbol('n', negative=True) + assert LambertW(n).is_zero is False + + +def test_issue_5673(): + e = LambertW(-1) + assert e.is_comparable is False + assert e.is_positive is not True + e2 = 1 - 1/(1 - exp(-1000)) + assert e2.is_positive is not True + e3 = -2 + exp(exp(LambertW(log(2)))*LambertW(log(2))) + assert e3.is_nonzero is not True + + +def test_log_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: log(x).fdiff(2)) + + +def test_log_taylor_term(): + x = symbols('x') + assert log(x).taylor_term(0, x) == x + assert log(x).taylor_term(1, x) == -x**2/2 + assert log(x).taylor_term(4, x) == x**5/5 + assert log(x).taylor_term(-1, x) is S.Zero + + +def test_exp_expand_NC(): + A, B, C = symbols('A,B,C', commutative=False) + + assert exp(A + B).expand() == exp(A + B) + assert exp(A + B + C).expand() == exp(A + B + C) + assert exp(x + y).expand() == exp(x)*exp(y) + assert exp(x + y + z).expand() == exp(x)*exp(y)*exp(z) + + +@_both_exp_pow +def test_as_numer_denom(): + n = symbols('n', negative=True) + assert exp(x).as_numer_denom() == (exp(x), 1) + assert exp(-x).as_numer_denom() == (1, exp(x)) + assert exp(-2*x).as_numer_denom() == (1, exp(2*x)) + assert exp(-2).as_numer_denom() == (1, exp(2)) + assert exp(n).as_numer_denom() == (1, exp(-n)) + assert exp(-n).as_numer_denom() == (exp(-n), 1) + assert exp(-I*x).as_numer_denom() == (1, exp(I*x)) + assert exp(-I*n).as_numer_denom() == (1, exp(I*n)) + assert exp(-n).as_numer_denom() == (exp(-n), 1) + # Check noncommutativity + a = symbols('a', commutative=False) + assert exp(-a).as_numer_denom() == (exp(-a), 1) + + +@_both_exp_pow +def test_polar(): + x, y = symbols('x y', polar=True) + + assert abs(exp_polar(I*4)) == 1 + assert abs(exp_polar(0)) == 1 + assert abs(exp_polar(2 + 3*I)) == exp(2) + assert exp_polar(I*10).n() == exp_polar(I*10) + + assert log(exp_polar(z)) == z + assert log(x*y).expand() == log(x) + log(y) + assert log(x**z).expand() == z*log(x) + + assert exp_polar(3).exp == 3 + + # Compare exp(1.0*pi*I). + assert (exp_polar(1.0*pi*I).n(n=5)).as_real_imag()[1] >= 0 + + assert exp_polar(0).is_rational is True # issue 8008 + + +def test_exp_summation(): + w = symbols("w") + m, n, i, j = symbols("m n i j") + expr = exp(Sum(w*i, (i, 0, n), (j, 0, m))) + assert expr.expand() == Product(exp(w*i), (i, 0, n), (j, 0, m)) + + +def test_log_product(): + from sympy.abc import n, m + + i, j = symbols('i,j', positive=True, integer=True) + x, y = symbols('x,y', positive=True) + z = symbols('z', real=True) + w = symbols('w') + + expr = log(Product(x**i, (i, 1, n))) + assert simplify(expr) == expr + assert expr.expand() == Sum(i*log(x), (i, 1, n)) + expr = log(Product(x**i*y**j, (i, 1, n), (j, 1, m))) + assert simplify(expr) == expr + assert expr.expand() == Sum(i*log(x) + j*log(y), (i, 1, n), (j, 1, m)) + + expr = log(Product(-2, (n, 0, 4))) + assert simplify(expr) == expr + assert expr.expand() == expr + assert expr.expand(force=True) == Sum(log(-2), (n, 0, 4)) + + expr = log(Product(exp(z*i), (i, 0, n))) + assert expr.expand() == Sum(z*i, (i, 0, n)) + + expr = log(Product(exp(w*i), (i, 0, n))) + assert expr.expand() == expr + assert expr.expand(force=True) == Sum(w*i, (i, 0, n)) + + expr = log(Product(i**2*abs(j), (i, 1, n), (j, 1, m))) + assert expr.expand() == Sum(2*log(i) + log(j), (i, 1, n), (j, 1, m)) + + +@XFAIL +def test_log_product_simplify_to_sum(): + from sympy.abc import n, m + i, j = symbols('i,j', positive=True, integer=True) + x, y = symbols('x,y', positive=True) + assert simplify(log(Product(x**i, (i, 1, n)))) == Sum(i*log(x), (i, 1, n)) + assert simplify(log(Product(x**i*y**j, (i, 1, n), (j, 1, m)))) == \ + Sum(i*log(x) + j*log(y), (i, 1, n), (j, 1, m)) + + +def test_issue_8866(): + assert simplify(log(x, 10, evaluate=False)) == simplify(log(x, 10)) + assert expand_log(log(x, 10, evaluate=False)) == expand_log(log(x, 10)) + + y = Symbol('y', positive=True) + l1 = log(exp(y), exp(10)) + b1 = log(exp(y), exp(5)) + l2 = log(exp(y), exp(10), evaluate=False) + b2 = log(exp(y), exp(5), evaluate=False) + assert simplify(log(l1, b1)) == simplify(log(l2, b2)) + assert expand_log(log(l1, b1)) == expand_log(log(l2, b2)) + + +def test_log_expand_factor(): + assert (log(18)/log(3) - 2).expand(factor=True) == log(2)/log(3) + assert (log(12)/log(2)).expand(factor=True) == log(3)/log(2) + 2 + assert (log(15)/log(3)).expand(factor=True) == 1 + log(5)/log(3) + assert (log(2)/(-log(12) + log(24))).expand(factor=True) == 1 + + assert expand_log(log(12), factor=True) == log(3) + 2*log(2) + assert expand_log(log(21)/log(7), factor=False) == log(3)/log(7) + 1 + assert expand_log(log(45)/log(5) + log(20), factor=False) == \ + 1 + 2*log(3)/log(5) + log(20) + assert expand_log(log(45)/log(5) + log(26), factor=True) == \ + log(2) + log(13) + (log(5) + 2*log(3))/log(5) + + +def test_issue_9116(): + n = Symbol('n', positive=True, integer=True) + assert log(n).is_nonnegative is True + + +def test_issue_18473(): + assert exp(x*log(cos(1/x))).as_leading_term(x) == S.NaN + assert exp(x*log(tan(1/x))).as_leading_term(x) == S.NaN + assert log(cos(1/x)).as_leading_term(x) == S.NaN + assert log(tan(1/x)).as_leading_term(x) == S.NaN + assert log(cos(1/x) + 2).as_leading_term(x) == AccumBounds(0, log(3)) + assert exp(x*log(cos(1/x) + 2)).as_leading_term(x) == 1 + assert log(cos(1/x) - 2).as_leading_term(x) == S.NaN + assert exp(x*log(cos(1/x) - 2)).as_leading_term(x) == S.NaN + assert log(cos(1/x) + 1).as_leading_term(x) == AccumBounds(-oo, log(2)) + assert exp(x*log(cos(1/x) + 1)).as_leading_term(x) == AccumBounds(0, 1) + assert log(sin(1/x)**2).as_leading_term(x) == AccumBounds(-oo, 0) + assert exp(x*log(sin(1/x)**2)).as_leading_term(x) == AccumBounds(0, 1) + assert log(tan(1/x)**2).as_leading_term(x) == AccumBounds(-oo, oo) + assert exp(2*x*(log(tan(1/x)**2))).as_leading_term(x) == AccumBounds(0, oo) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_hyperbolic.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_hyperbolic.py new file mode 100644 index 0000000000000000000000000000000000000000..1ad9f1d51598b9d605b0472e254c5a710d4ed4f5 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_hyperbolic.py @@ -0,0 +1,1553 @@ +from sympy.calculus.accumulationbounds import AccumBounds +from sympy.core.function import (expand_mul, expand_trig) +from sympy.core.numbers import (E, I, Integer, Rational, nan, oo, pi, zoo) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.complexes import (im, re) +from sympy.functions.elementary.exponential import (exp, log) +from sympy.functions.elementary.hyperbolic import (acosh, acoth, acsch, asech, asinh, atanh, cosh, coth, csch, sech, sinh, tanh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (acos, asin, cos, cot, sec, sin, tan) +from sympy.series.order import O + +from sympy.core.expr import unchanged +from sympy.core.function import ArgumentIndexError, PoleError +from sympy.testing.pytest import raises + + +def test_sinh(): + x, y = symbols('x,y') + + k = Symbol('k', integer=True) + + assert sinh(nan) is nan + assert sinh(zoo) is nan + + assert sinh(oo) is oo + assert sinh(-oo) is -oo + + assert sinh(0) == 0 + + assert unchanged(sinh, 1) + assert sinh(-1) == -sinh(1) + + assert unchanged(sinh, x) + assert sinh(-x) == -sinh(x) + + assert unchanged(sinh, pi) + assert sinh(-pi) == -sinh(pi) + + assert unchanged(sinh, 2**1024 * E) + assert sinh(-2**1024 * E) == -sinh(2**1024 * E) + + assert sinh(pi*I) == 0 + assert sinh(-pi*I) == 0 + assert sinh(2*pi*I) == 0 + assert sinh(-2*pi*I) == 0 + assert sinh(-3*10**73*pi*I) == 0 + assert sinh(7*10**103*pi*I) == 0 + + assert sinh(pi*I/2) == I + assert sinh(-pi*I/2) == -I + assert sinh(pi*I*Rational(5, 2)) == I + assert sinh(pi*I*Rational(7, 2)) == -I + + assert sinh(pi*I/3) == S.Half*sqrt(3)*I + assert sinh(pi*I*Rational(-2, 3)) == Rational(-1, 2)*sqrt(3)*I + + assert sinh(pi*I/4) == S.Half*sqrt(2)*I + assert sinh(-pi*I/4) == Rational(-1, 2)*sqrt(2)*I + assert sinh(pi*I*Rational(17, 4)) == S.Half*sqrt(2)*I + assert sinh(pi*I*Rational(-3, 4)) == Rational(-1, 2)*sqrt(2)*I + + assert sinh(pi*I/6) == S.Half*I + assert sinh(-pi*I/6) == Rational(-1, 2)*I + assert sinh(pi*I*Rational(7, 6)) == Rational(-1, 2)*I + assert sinh(pi*I*Rational(-5, 6)) == Rational(-1, 2)*I + + assert sinh(pi*I/105) == sin(pi/105)*I + assert sinh(-pi*I/105) == -sin(pi/105)*I + + assert unchanged(sinh, 2 + 3*I) + + assert sinh(x*I) == sin(x)*I + + assert sinh(k*pi*I) == 0 + assert sinh(17*k*pi*I) == 0 + + assert sinh(k*pi*I/2) == sin(k*pi/2)*I + + assert sinh(x).as_real_imag(deep=False) == (cos(im(x))*sinh(re(x)), + sin(im(x))*cosh(re(x))) + x = Symbol('x', extended_real=True) + assert sinh(x).as_real_imag(deep=False) == (sinh(x), 0) + + x = Symbol('x', real=True) + assert sinh(I*x).is_finite is True + assert sinh(x).is_real is True + assert sinh(I).is_real is False + p = Symbol('p', positive=True) + assert sinh(p).is_zero is False + assert sinh(0, evaluate=False).is_zero is True + assert sinh(2*pi*I, evaluate=False).is_zero is True + + +def test_sinh_series(): + x = Symbol('x') + assert sinh(x).series(x, 0, 10) == \ + x + x**3/6 + x**5/120 + x**7/5040 + x**9/362880 + O(x**10) + + +def test_sinh_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: sinh(x).fdiff(2)) + + +def test_cosh(): + x, y = symbols('x,y') + + k = Symbol('k', integer=True) + + assert cosh(nan) is nan + assert cosh(zoo) is nan + + assert cosh(oo) is oo + assert cosh(-oo) is oo + + assert cosh(0) == 1 + + assert unchanged(cosh, 1) + assert cosh(-1) == cosh(1) + + assert unchanged(cosh, x) + assert cosh(-x) == cosh(x) + + assert cosh(pi*I) == cos(pi) + assert cosh(-pi*I) == cos(pi) + + assert unchanged(cosh, 2**1024 * E) + assert cosh(-2**1024 * E) == cosh(2**1024 * E) + + assert cosh(pi*I/2) == 0 + assert cosh(-pi*I/2) == 0 + assert cosh((-3*10**73 + 1)*pi*I/2) == 0 + assert cosh((7*10**103 + 1)*pi*I/2) == 0 + + assert cosh(pi*I) == -1 + assert cosh(-pi*I) == -1 + assert cosh(5*pi*I) == -1 + assert cosh(8*pi*I) == 1 + + assert cosh(pi*I/3) == S.Half + assert cosh(pi*I*Rational(-2, 3)) == Rational(-1, 2) + + assert cosh(pi*I/4) == S.Half*sqrt(2) + assert cosh(-pi*I/4) == S.Half*sqrt(2) + assert cosh(pi*I*Rational(11, 4)) == Rational(-1, 2)*sqrt(2) + assert cosh(pi*I*Rational(-3, 4)) == Rational(-1, 2)*sqrt(2) + + assert cosh(pi*I/6) == S.Half*sqrt(3) + assert cosh(-pi*I/6) == S.Half*sqrt(3) + assert cosh(pi*I*Rational(7, 6)) == Rational(-1, 2)*sqrt(3) + assert cosh(pi*I*Rational(-5, 6)) == Rational(-1, 2)*sqrt(3) + + assert cosh(pi*I/105) == cos(pi/105) + assert cosh(-pi*I/105) == cos(pi/105) + + assert unchanged(cosh, 2 + 3*I) + + assert cosh(x*I) == cos(x) + + assert cosh(k*pi*I) == cos(k*pi) + assert cosh(17*k*pi*I) == cos(17*k*pi) + + assert unchanged(cosh, k*pi) + + assert cosh(x).as_real_imag(deep=False) == (cos(im(x))*cosh(re(x)), + sin(im(x))*sinh(re(x))) + x = Symbol('x', extended_real=True) + assert cosh(x).as_real_imag(deep=False) == (cosh(x), 0) + + x = Symbol('x', real=True) + assert cosh(I*x).is_finite is True + assert cosh(I*x).is_real is True + assert cosh(I*2 + 1).is_real is False + assert cosh(5*I*S.Pi/2, evaluate=False).is_zero is True + assert cosh(x).is_zero is False + + +def test_cosh_series(): + x = Symbol('x') + assert cosh(x).series(x, 0, 10) == \ + 1 + x**2/2 + x**4/24 + x**6/720 + x**8/40320 + O(x**10) + + +def test_cosh_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: cosh(x).fdiff(2)) + + +def test_tanh(): + x, y = symbols('x,y') + + k = Symbol('k', integer=True) + + assert tanh(nan) is nan + assert tanh(zoo) is nan + + assert tanh(oo) == 1 + assert tanh(-oo) == -1 + + assert tanh(0) == 0 + + assert unchanged(tanh, 1) + assert tanh(-1) == -tanh(1) + + assert unchanged(tanh, x) + assert tanh(-x) == -tanh(x) + + assert unchanged(tanh, pi) + assert tanh(-pi) == -tanh(pi) + + assert unchanged(tanh, 2**1024 * E) + assert tanh(-2**1024 * E) == -tanh(2**1024 * E) + + assert tanh(pi*I) == 0 + assert tanh(-pi*I) == 0 + assert tanh(2*pi*I) == 0 + assert tanh(-2*pi*I) == 0 + assert tanh(-3*10**73*pi*I) == 0 + assert tanh(7*10**103*pi*I) == 0 + + assert tanh(pi*I/2) is zoo + assert tanh(-pi*I/2) is zoo + assert tanh(pi*I*Rational(5, 2)) is zoo + assert tanh(pi*I*Rational(7, 2)) is zoo + + assert tanh(pi*I/3) == sqrt(3)*I + assert tanh(pi*I*Rational(-2, 3)) == sqrt(3)*I + + assert tanh(pi*I/4) == I + assert tanh(-pi*I/4) == -I + assert tanh(pi*I*Rational(17, 4)) == I + assert tanh(pi*I*Rational(-3, 4)) == I + + assert tanh(pi*I/6) == I/sqrt(3) + assert tanh(-pi*I/6) == -I/sqrt(3) + assert tanh(pi*I*Rational(7, 6)) == I/sqrt(3) + assert tanh(pi*I*Rational(-5, 6)) == I/sqrt(3) + + assert tanh(pi*I/105) == tan(pi/105)*I + assert tanh(-pi*I/105) == -tan(pi/105)*I + + assert unchanged(tanh, 2 + 3*I) + + assert tanh(x*I) == tan(x)*I + + assert tanh(k*pi*I) == 0 + assert tanh(17*k*pi*I) == 0 + + assert tanh(k*pi*I/2) == tan(k*pi/2)*I + + assert tanh(x).as_real_imag(deep=False) == (sinh(re(x))*cosh(re(x))/(cos(im(x))**2 + + sinh(re(x))**2), + sin(im(x))*cos(im(x))/(cos(im(x))**2 + sinh(re(x))**2)) + x = Symbol('x', extended_real=True) + assert tanh(x).as_real_imag(deep=False) == (tanh(x), 0) + assert tanh(I*pi/3 + 1).is_real is False + assert tanh(x).is_real is True + assert tanh(I*pi*x/2).is_real is None + + +def test_tanh_series(): + x = Symbol('x') + assert tanh(x).series(x, 0, 10) == \ + x - x**3/3 + 2*x**5/15 - 17*x**7/315 + 62*x**9/2835 + O(x**10) + + +def test_tanh_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: tanh(x).fdiff(2)) + + +def test_coth(): + x, y = symbols('x,y') + + k = Symbol('k', integer=True) + + assert coth(nan) is nan + assert coth(zoo) is nan + + assert coth(oo) == 1 + assert coth(-oo) == -1 + + assert coth(0) is zoo + assert unchanged(coth, 1) + assert coth(-1) == -coth(1) + + assert unchanged(coth, x) + assert coth(-x) == -coth(x) + + assert coth(pi*I) == -I*cot(pi) + assert coth(-pi*I) == cot(pi)*I + + assert unchanged(coth, 2**1024 * E) + assert coth(-2**1024 * E) == -coth(2**1024 * E) + + assert coth(pi*I) == -I*cot(pi) + assert coth(-pi*I) == I*cot(pi) + assert coth(2*pi*I) == -I*cot(2*pi) + assert coth(-2*pi*I) == I*cot(2*pi) + assert coth(-3*10**73*pi*I) == I*cot(3*10**73*pi) + assert coth(7*10**103*pi*I) == -I*cot(7*10**103*pi) + + assert coth(pi*I/2) == 0 + assert coth(-pi*I/2) == 0 + assert coth(pi*I*Rational(5, 2)) == 0 + assert coth(pi*I*Rational(7, 2)) == 0 + + assert coth(pi*I/3) == -I/sqrt(3) + assert coth(pi*I*Rational(-2, 3)) == -I/sqrt(3) + + assert coth(pi*I/4) == -I + assert coth(-pi*I/4) == I + assert coth(pi*I*Rational(17, 4)) == -I + assert coth(pi*I*Rational(-3, 4)) == -I + + assert coth(pi*I/6) == -sqrt(3)*I + assert coth(-pi*I/6) == sqrt(3)*I + assert coth(pi*I*Rational(7, 6)) == -sqrt(3)*I + assert coth(pi*I*Rational(-5, 6)) == -sqrt(3)*I + + assert coth(pi*I/105) == -cot(pi/105)*I + assert coth(-pi*I/105) == cot(pi/105)*I + + assert unchanged(coth, 2 + 3*I) + + assert coth(x*I) == -cot(x)*I + + assert coth(k*pi*I) == -cot(k*pi)*I + assert coth(17*k*pi*I) == -cot(17*k*pi)*I + + assert coth(k*pi*I) == -cot(k*pi)*I + + assert coth(log(tan(2))) == coth(log(-tan(2))) + assert coth(1 + I*pi/2) == tanh(1) + + assert coth(x).as_real_imag(deep=False) == (sinh(re(x))*cosh(re(x))/(sin(im(x))**2 + + sinh(re(x))**2), + -sin(im(x))*cos(im(x))/(sin(im(x))**2 + sinh(re(x))**2)) + x = Symbol('x', extended_real=True) + assert coth(x).as_real_imag(deep=False) == (coth(x), 0) + + assert expand_trig(coth(2*x)) == (coth(x)**2 + 1)/(2*coth(x)) + assert expand_trig(coth(3*x)) == (coth(x)**3 + 3*coth(x))/(1 + 3*coth(x)**2) + + assert expand_trig(coth(x + y)) == (1 + coth(x)*coth(y))/(coth(x) + coth(y)) + + +def test_coth_series(): + x = Symbol('x') + assert coth(x).series(x, 0, 8) == \ + 1/x + x/3 - x**3/45 + 2*x**5/945 - x**7/4725 + O(x**8) + + +def test_coth_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: coth(x).fdiff(2)) + + +def test_csch(): + x, y = symbols('x,y') + + k = Symbol('k', integer=True) + n = Symbol('n', positive=True) + + assert csch(nan) is nan + assert csch(zoo) is nan + + assert csch(oo) == 0 + assert csch(-oo) == 0 + + assert csch(0) is zoo + + assert csch(-1) == -csch(1) + + assert csch(-x) == -csch(x) + assert csch(-pi) == -csch(pi) + assert csch(-2**1024 * E) == -csch(2**1024 * E) + + assert csch(pi*I) is zoo + assert csch(-pi*I) is zoo + assert csch(2*pi*I) is zoo + assert csch(-2*pi*I) is zoo + assert csch(-3*10**73*pi*I) is zoo + assert csch(7*10**103*pi*I) is zoo + + assert csch(pi*I/2) == -I + assert csch(-pi*I/2) == I + assert csch(pi*I*Rational(5, 2)) == -I + assert csch(pi*I*Rational(7, 2)) == I + + assert csch(pi*I/3) == -2/sqrt(3)*I + assert csch(pi*I*Rational(-2, 3)) == 2/sqrt(3)*I + + assert csch(pi*I/4) == -sqrt(2)*I + assert csch(-pi*I/4) == sqrt(2)*I + assert csch(pi*I*Rational(7, 4)) == sqrt(2)*I + assert csch(pi*I*Rational(-3, 4)) == sqrt(2)*I + + assert csch(pi*I/6) == -2*I + assert csch(-pi*I/6) == 2*I + assert csch(pi*I*Rational(7, 6)) == 2*I + assert csch(pi*I*Rational(-7, 6)) == -2*I + assert csch(pi*I*Rational(-5, 6)) == 2*I + + assert csch(pi*I/105) == -1/sin(pi/105)*I + assert csch(-pi*I/105) == 1/sin(pi/105)*I + + assert csch(x*I) == -1/sin(x)*I + + assert csch(k*pi*I) is zoo + assert csch(17*k*pi*I) is zoo + + assert csch(k*pi*I/2) == -1/sin(k*pi/2)*I + + assert csch(n).is_real is True + + assert expand_trig(csch(x + y)) == 1/(sinh(x)*cosh(y) + cosh(x)*sinh(y)) + + +def test_csch_series(): + x = Symbol('x') + assert csch(x).series(x, 0, 10) == \ + 1/ x - x/6 + 7*x**3/360 - 31*x**5/15120 + 127*x**7/604800 \ + - 73*x**9/3421440 + O(x**10) + + +def test_csch_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: csch(x).fdiff(2)) + + +def test_sech(): + x, y = symbols('x, y') + + k = Symbol('k', integer=True) + n = Symbol('n', positive=True) + + assert sech(nan) is nan + assert sech(zoo) is nan + + assert sech(oo) == 0 + assert sech(-oo) == 0 + + assert sech(0) == 1 + + assert sech(-1) == sech(1) + assert sech(-x) == sech(x) + + assert sech(pi*I) == sec(pi) + + assert sech(-pi*I) == sec(pi) + assert sech(-2**1024 * E) == sech(2**1024 * E) + + assert sech(pi*I/2) is zoo + assert sech(-pi*I/2) is zoo + assert sech((-3*10**73 + 1)*pi*I/2) is zoo + assert sech((7*10**103 + 1)*pi*I/2) is zoo + + assert sech(pi*I) == -1 + assert sech(-pi*I) == -1 + assert sech(5*pi*I) == -1 + assert sech(8*pi*I) == 1 + + assert sech(pi*I/3) == 2 + assert sech(pi*I*Rational(-2, 3)) == -2 + + assert sech(pi*I/4) == sqrt(2) + assert sech(-pi*I/4) == sqrt(2) + assert sech(pi*I*Rational(5, 4)) == -sqrt(2) + assert sech(pi*I*Rational(-5, 4)) == -sqrt(2) + + assert sech(pi*I/6) == 2/sqrt(3) + assert sech(-pi*I/6) == 2/sqrt(3) + assert sech(pi*I*Rational(7, 6)) == -2/sqrt(3) + assert sech(pi*I*Rational(-5, 6)) == -2/sqrt(3) + + assert sech(pi*I/105) == 1/cos(pi/105) + assert sech(-pi*I/105) == 1/cos(pi/105) + + assert sech(x*I) == 1/cos(x) + + assert sech(k*pi*I) == 1/cos(k*pi) + assert sech(17*k*pi*I) == 1/cos(17*k*pi) + + assert sech(n).is_real is True + + assert expand_trig(sech(x + y)) == 1/(cosh(x)*cosh(y) + sinh(x)*sinh(y)) + + +def test_sech_series(): + x = Symbol('x') + assert sech(x).series(x, 0, 10) == \ + 1 - x**2/2 + 5*x**4/24 - 61*x**6/720 + 277*x**8/8064 + O(x**10) + + +def test_sech_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: sech(x).fdiff(2)) + + +def test_asinh(): + x, y = symbols('x,y') + assert unchanged(asinh, x) + assert asinh(-x) == -asinh(x) + + # at specific points + assert asinh(nan) is nan + assert asinh( 0) == 0 + assert asinh(+1) == log(sqrt(2) + 1) + + assert asinh(-1) == log(sqrt(2) - 1) + assert asinh(I) == pi*I/2 + assert asinh(-I) == -pi*I/2 + assert asinh(I/2) == pi*I/6 + assert asinh(-I/2) == -pi*I/6 + + # at infinites + assert asinh(oo) is oo + assert asinh(-oo) is -oo + + assert asinh(I*oo) is oo + assert asinh(-I *oo) is -oo + + assert asinh(zoo) is zoo + + # properties + assert asinh(I *(sqrt(3) - 1)/(2**Rational(3, 2))) == pi*I/12 + assert asinh(-I *(sqrt(3) - 1)/(2**Rational(3, 2))) == -pi*I/12 + + assert asinh(I*(sqrt(5) - 1)/4) == pi*I/10 + assert asinh(-I*(sqrt(5) - 1)/4) == -pi*I/10 + + assert asinh(I*(sqrt(5) + 1)/4) == pi*I*Rational(3, 10) + assert asinh(-I*(sqrt(5) + 1)/4) == pi*I*Rational(-3, 10) + + # reality + assert asinh(S(2)).is_real is True + assert asinh(S(2)).is_finite is True + assert asinh(S(-2)).is_real is True + assert asinh(S(oo)).is_extended_real is True + assert asinh(-S(oo)).is_real is False + assert (asinh(2) - oo) == -oo + assert asinh(symbols('y', real=True)).is_real is True + + # Symmetry + assert asinh(Rational(-1, 2)) == -asinh(S.Half) + + # inverse composition + assert unchanged(asinh, sinh(Symbol('v1'))) + + assert asinh(sinh(0, evaluate=False)) == 0 + assert asinh(sinh(-3, evaluate=False)) == -3 + assert asinh(sinh(2, evaluate=False)) == 2 + assert asinh(sinh(I, evaluate=False)) == I + assert asinh(sinh(-I, evaluate=False)) == -I + assert asinh(sinh(5*I, evaluate=False)) == -2*I*pi + 5*I + assert asinh(sinh(15 + 11*I)) == 15 - 4*I*pi + 11*I + assert asinh(sinh(-73 + 97*I)) == 73 - 97*I + 31*I*pi + assert asinh(sinh(-7 - 23*I)) == 7 - 7*I*pi + 23*I + assert asinh(sinh(13 - 3*I)) == -13 - I*pi + 3*I + p = Symbol('p', positive=True) + assert asinh(p).is_zero is False + assert asinh(sinh(0, evaluate=False), evaluate=False).is_zero is True + + +def test_asinh_rewrite(): + x = Symbol('x') + assert asinh(x).rewrite(log) == log(x + sqrt(x**2 + 1)) + assert asinh(x).rewrite(atanh) == atanh(x/sqrt(1 + x**2)) + assert asinh(x).rewrite(asin) == -I*asin(I*x, evaluate=False) + assert asinh(x*(1 + I)).rewrite(asin) == -I*asin(I*x*(1+I)) + assert asinh(x).rewrite(acos) == I*acos(I*x, evaluate=False) - I*pi/2 + + +def test_asinh_leading_term(): + x = Symbol('x') + assert asinh(x).as_leading_term(x, cdir=1) == x + # Tests concerning branch points + assert asinh(x + I).as_leading_term(x, cdir=1) == I*pi/2 + assert asinh(x - I).as_leading_term(x, cdir=1) == -I*pi/2 + assert asinh(1/x).as_leading_term(x, cdir=1) == -log(x) + log(2) + assert asinh(1/x).as_leading_term(x, cdir=-1) == log(x) - log(2) - I*pi + # Tests concerning points lying on branch cuts + assert asinh(x + 2*I).as_leading_term(x, cdir=1) == I*asin(2) + assert asinh(x + 2*I).as_leading_term(x, cdir=-1) == -I*asin(2) + I*pi + assert asinh(x - 2*I).as_leading_term(x, cdir=1) == -I*pi + I*asin(2) + assert asinh(x - 2*I).as_leading_term(x, cdir=-1) == -I*asin(2) + # Tests concerning re(ndir) == 0 + assert asinh(2*I + I*x - x**2).as_leading_term(x, cdir=1) == log(2 - sqrt(3)) + I*pi/2 + assert asinh(2*I + I*x - x**2).as_leading_term(x, cdir=-1) == log(2 - sqrt(3)) + I*pi/2 + + +def test_asinh_series(): + x = Symbol('x') + assert asinh(x).series(x, 0, 8) == \ + x - x**3/6 + 3*x**5/40 - 5*x**7/112 + O(x**8) + t5 = asinh(x).taylor_term(5, x) + assert t5 == 3*x**5/40 + assert asinh(x).taylor_term(7, x, t5, 0) == -5*x**7/112 + + +def test_asinh_nseries(): + x = Symbol('x') + # Tests concerning branch points + assert asinh(x + I)._eval_nseries(x, 4, None) == I*pi/2 - \ + sqrt(2)*sqrt(I)*I*sqrt(x) + sqrt(2)*sqrt(I)*x**(S(3)/2)/12 + 3*sqrt(2)*sqrt(I)*I*x**(S(5)/2)/160 - \ + 5*sqrt(2)*sqrt(I)*x**(S(7)/2)/896 + O(x**4) + assert asinh(x - I)._eval_nseries(x, 4, None) == -I*pi/2 + \ + sqrt(2)*I*sqrt(x)*sqrt(-I) + sqrt(2)*x**(S(3)/2)*sqrt(-I)/12 - \ + 3*sqrt(2)*I*x**(S(5)/2)*sqrt(-I)/160 - 5*sqrt(2)*x**(S(7)/2)*sqrt(-I)/896 + O(x**4) + # Tests concerning points lying on branch cuts + assert asinh(x + 2*I)._eval_nseries(x, 4, None, cdir=1) == I*asin(2) - \ + sqrt(3)*I*x/3 + sqrt(3)*x**2/9 + sqrt(3)*I*x**3/18 + O(x**4) + assert asinh(x + 2*I)._eval_nseries(x, 4, None, cdir=-1) == I*pi - I*asin(2) + \ + sqrt(3)*I*x/3 - sqrt(3)*x**2/9 - sqrt(3)*I*x**3/18 + O(x**4) + assert asinh(x - 2*I)._eval_nseries(x, 4, None, cdir=1) == I*asin(2) - I*pi + \ + sqrt(3)*I*x/3 + sqrt(3)*x**2/9 - sqrt(3)*I*x**3/18 + O(x**4) + assert asinh(x - 2*I)._eval_nseries(x, 4, None, cdir=-1) == -I*asin(2) - \ + sqrt(3)*I*x/3 - sqrt(3)*x**2/9 + sqrt(3)*I*x**3/18 + O(x**4) + # Tests concerning re(ndir) == 0 + assert asinh(2*I + I*x - x**2)._eval_nseries(x, 4, None) == I*pi/2 + log(2 - sqrt(3)) + \ + x*(-3 + 2*sqrt(3))/(-6 + 3*sqrt(3)) + x**2*(12 - 36*I + sqrt(3)*(-7 + 21*I))/(-63 + \ + 36*sqrt(3)) + x**3*(-168 + sqrt(3)*(97 - 388*I) + 672*I)/(-1746 + 1008*sqrt(3)) + O(x**4) + + +def test_asinh_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: asinh(x).fdiff(2)) + + +def test_acosh(): + x = Symbol('x') + + assert unchanged(acosh, -x) + + #at specific points + assert acosh(1) == 0 + assert acosh(-1) == pi*I + assert acosh(0) == I*pi/2 + assert acosh(S.Half) == I*pi/3 + assert acosh(Rational(-1, 2)) == pi*I*Rational(2, 3) + assert acosh(nan) is nan + + # at infinites + assert acosh(oo) is oo + assert acosh(-oo) is oo + + assert acosh(I*oo) == oo + I*pi/2 + assert acosh(-I*oo) == oo - I*pi/2 + + assert acosh(zoo) is zoo + + assert acosh(I) == log(I*(1 + sqrt(2))) + assert acosh(-I) == log(-I*(1 + sqrt(2))) + assert acosh((sqrt(3) - 1)/(2*sqrt(2))) == pi*I*Rational(5, 12) + assert acosh(-(sqrt(3) - 1)/(2*sqrt(2))) == pi*I*Rational(7, 12) + assert acosh(sqrt(2)/2) == I*pi/4 + assert acosh(-sqrt(2)/2) == I*pi*Rational(3, 4) + assert acosh(sqrt(3)/2) == I*pi/6 + assert acosh(-sqrt(3)/2) == I*pi*Rational(5, 6) + assert acosh(sqrt(2 + sqrt(2))/2) == I*pi/8 + assert acosh(-sqrt(2 + sqrt(2))/2) == I*pi*Rational(7, 8) + assert acosh(sqrt(2 - sqrt(2))/2) == I*pi*Rational(3, 8) + assert acosh(-sqrt(2 - sqrt(2))/2) == I*pi*Rational(5, 8) + assert acosh((1 + sqrt(3))/(2*sqrt(2))) == I*pi/12 + assert acosh(-(1 + sqrt(3))/(2*sqrt(2))) == I*pi*Rational(11, 12) + assert acosh((sqrt(5) + 1)/4) == I*pi/5 + assert acosh(-(sqrt(5) + 1)/4) == I*pi*Rational(4, 5) + + assert str(acosh(5*I).n(6)) == '2.31244 + 1.5708*I' + assert str(acosh(-5*I).n(6)) == '2.31244 - 1.5708*I' + + # inverse composition + assert unchanged(acosh, Symbol('v1')) + + assert acosh(cosh(-3, evaluate=False)) == 3 + assert acosh(cosh(3, evaluate=False)) == 3 + assert acosh(cosh(0, evaluate=False)) == 0 + assert acosh(cosh(I, evaluate=False)) == I + assert acosh(cosh(-I, evaluate=False)) == I + assert acosh(cosh(7*I, evaluate=False)) == -2*I*pi + 7*I + assert acosh(cosh(1 + I)) == 1 + I + assert acosh(cosh(3 - 3*I)) == 3 - 3*I + assert acosh(cosh(-3 + 2*I)) == 3 - 2*I + assert acosh(cosh(-5 - 17*I)) == 5 - 6*I*pi + 17*I + assert acosh(cosh(-21 + 11*I)) == 21 - 11*I + 4*I*pi + assert acosh(cosh(cosh(1) + I)) == cosh(1) + I + assert acosh(1, evaluate=False).is_zero is True + + # Reality + assert acosh(S(2)).is_real is True + assert acosh(S(2)).is_extended_real is True + assert acosh(oo).is_extended_real is True + assert acosh(S(2)).is_finite is True + assert acosh(S(1) / 5).is_real is False + assert (acosh(2) - oo) == -oo + assert acosh(symbols('y', real=True)).is_real is None + + +def test_acosh_rewrite(): + x = Symbol('x') + assert acosh(x).rewrite(log) == log(x + sqrt(x - 1)*sqrt(x + 1)) + assert acosh(x).rewrite(asin) == sqrt(x - 1)*(-asin(x) + pi/2)/sqrt(1 - x) + assert acosh(x).rewrite(asinh) == sqrt(x - 1)*(I*asinh(I*x, evaluate=False) + pi/2)/sqrt(1 - x) + assert acosh(x).rewrite(atanh) == \ + (sqrt(x - 1)*sqrt(x + 1)*atanh(sqrt(x**2 - 1)/x)/sqrt(x**2 - 1) + + pi*sqrt(x - 1)*(-x*sqrt(x**(-2)) + 1)/(2*sqrt(1 - x))) + x = Symbol('x', positive=True) + assert acosh(x).rewrite(atanh) == \ + sqrt(x - 1)*sqrt(x + 1)*atanh(sqrt(x**2 - 1)/x)/sqrt(x**2 - 1) + + +def test_acosh_leading_term(): + x = Symbol('x') + # Tests concerning branch points + assert acosh(x).as_leading_term(x) == I*pi/2 + assert acosh(x + 1).as_leading_term(x) == sqrt(2)*sqrt(x) + assert acosh(x - 1).as_leading_term(x) == I*pi + assert acosh(1/x).as_leading_term(x, cdir=1) == -log(x) + log(2) + assert acosh(1/x).as_leading_term(x, cdir=-1) == -log(x) + log(2) + 2*I*pi + # Tests concerning points lying on branch cuts + assert acosh(I*x - 2).as_leading_term(x, cdir=1) == acosh(-2) + assert acosh(-I*x - 2).as_leading_term(x, cdir=1) == -2*I*pi + acosh(-2) + assert acosh(x**2 - I*x + S(1)/3).as_leading_term(x, cdir=1) == -acosh(S(1)/3) + assert acosh(x**2 - I*x + S(1)/3).as_leading_term(x, cdir=-1) == acosh(S(1)/3) + assert acosh(1/(I*x - 3)).as_leading_term(x, cdir=1) == -acosh(-S(1)/3) + assert acosh(1/(I*x - 3)).as_leading_term(x, cdir=-1) == acosh(-S(1)/3) + # Tests concerning im(ndir) == 0 + assert acosh(-I*x**2 + x - 2).as_leading_term(x, cdir=1) == log(sqrt(3) + 2) - I*pi + assert acosh(-I*x**2 + x - 2).as_leading_term(x, cdir=-1) == log(sqrt(3) + 2) - I*pi + + +def test_acosh_series(): + x = Symbol('x') + assert acosh(x).series(x, 0, 8) == \ + -I*x + pi*I/2 - I*x**3/6 - 3*I*x**5/40 - 5*I*x**7/112 + O(x**8) + t5 = acosh(x).taylor_term(5, x) + assert t5 == - 3*I*x**5/40 + assert acosh(x).taylor_term(7, x, t5, 0) == - 5*I*x**7/112 + + +def test_acosh_nseries(): + x = Symbol('x') + # Tests concerning branch points + assert acosh(x + 1)._eval_nseries(x, 4, None) == sqrt(2)*sqrt(x) - \ + sqrt(2)*x**(S(3)/2)/12 + 3*sqrt(2)*x**(S(5)/2)/160 - 5*sqrt(2)*x**(S(7)/2)/896 + O(x**4) + # Tests concerning points lying on branch cuts + assert acosh(x - 1)._eval_nseries(x, 4, None) == I*pi - \ + sqrt(2)*I*sqrt(x) - sqrt(2)*I*x**(S(3)/2)/12 - 3*sqrt(2)*I*x**(S(5)/2)/160 - \ + 5*sqrt(2)*I*x**(S(7)/2)/896 + O(x**4) + assert acosh(I*x - 2)._eval_nseries(x, 4, None, cdir=1) == acosh(-2) - \ + sqrt(3)*I*x/3 + sqrt(3)*x**2/9 + sqrt(3)*I*x**3/18 + O(x**4) + assert acosh(-I*x - 2)._eval_nseries(x, 4, None, cdir=1) == acosh(-2) - \ + 2*I*pi + sqrt(3)*I*x/3 + sqrt(3)*x**2/9 - sqrt(3)*I*x**3/18 + O(x**4) + assert acosh(1/(I*x - 3))._eval_nseries(x, 4, None, cdir=1) == -acosh(-S(1)/3) + \ + sqrt(2)*x/12 + 17*sqrt(2)*I*x**2/576 - 443*sqrt(2)*x**3/41472 + O(x**4) + assert acosh(1/(I*x - 3))._eval_nseries(x, 4, None, cdir=-1) == acosh(-S(1)/3) - \ + sqrt(2)*x/12 - 17*sqrt(2)*I*x**2/576 + 443*sqrt(2)*x**3/41472 + O(x**4) + # Tests concerning im(ndir) == 0 + assert acosh(-I*x**2 + x - 2)._eval_nseries(x, 4, None) == -I*pi + log(sqrt(3) + 2) + \ + x*(-2*sqrt(3) - 3)/(3*sqrt(3) + 6) + x**2*(-12 + 36*I + sqrt(3)*(-7 + 21*I))/(36*sqrt(3) + \ + 63) + x**3*(-168 + 672*I + sqrt(3)*(-97 + 388*I))/(1008*sqrt(3) + 1746) + O(x**4) + + +def test_acosh_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: acosh(x).fdiff(2)) + + +def test_asech(): + x = Symbol('x') + + assert unchanged(asech, -x) + + # values at fixed points + assert asech(1) == 0 + assert asech(-1) == pi*I + assert asech(0) is oo + assert asech(2) == I*pi/3 + assert asech(-2) == 2*I*pi / 3 + assert asech(nan) is nan + + # at infinites + assert asech(oo) == I*pi/2 + assert asech(-oo) == I*pi/2 + assert asech(zoo) == I*AccumBounds(-pi/2, pi/2) + + assert asech(I) == log(1 + sqrt(2)) - I*pi/2 + assert asech(-I) == log(1 + sqrt(2)) + I*pi/2 + assert asech(sqrt(2) - sqrt(6)) == 11*I*pi / 12 + assert asech(sqrt(2 - 2/sqrt(5))) == I*pi / 10 + assert asech(-sqrt(2 - 2/sqrt(5))) == 9*I*pi / 10 + assert asech(2 / sqrt(2 + sqrt(2))) == I*pi / 8 + assert asech(-2 / sqrt(2 + sqrt(2))) == 7*I*pi / 8 + assert asech(sqrt(5) - 1) == I*pi / 5 + assert asech(1 - sqrt(5)) == 4*I*pi / 5 + assert asech(-sqrt(2*(2 + sqrt(2)))) == 5*I*pi / 8 + + # properties + # asech(x) == acosh(1/x) + assert asech(sqrt(2)) == acosh(1/sqrt(2)) + assert asech(2/sqrt(3)) == acosh(sqrt(3)/2) + assert asech(2/sqrt(2 + sqrt(2))) == acosh(sqrt(2 + sqrt(2))/2) + assert asech(2) == acosh(S.Half) + + # reality + assert asech(S(2)).is_real is False + assert asech(-S(1) / 3).is_real is False + assert asech(S(2) / 3).is_finite is True + assert asech(S(0)).is_real is False + assert asech(S(0)).is_extended_real is True + assert asech(symbols('y', real=True)).is_real is None + + # asech(x) == I*acos(1/x) + # (Note: the exact formula is asech(x) == +/- I*acos(1/x)) + assert asech(-sqrt(2)) == I*acos(-1/sqrt(2)) + assert asech(-2/sqrt(3)) == I*acos(-sqrt(3)/2) + assert asech(-S(2)) == I*acos(Rational(-1, 2)) + assert asech(-2/sqrt(2)) == I*acos(-sqrt(2)/2) + + # sech(asech(x)) / x == 1 + assert expand_mul(sech(asech(sqrt(6) - sqrt(2))) / (sqrt(6) - sqrt(2))) == 1 + assert expand_mul(sech(asech(sqrt(6) + sqrt(2))) / (sqrt(6) + sqrt(2))) == 1 + assert (sech(asech(sqrt(2 + 2/sqrt(5)))) / (sqrt(2 + 2/sqrt(5)))).simplify() == 1 + assert (sech(asech(-sqrt(2 + 2/sqrt(5)))) / (-sqrt(2 + 2/sqrt(5)))).simplify() == 1 + assert (sech(asech(sqrt(2*(2 + sqrt(2))))) / (sqrt(2*(2 + sqrt(2))))).simplify() == 1 + assert expand_mul(sech(asech(1 + sqrt(5))) / (1 + sqrt(5))) == 1 + assert expand_mul(sech(asech(-1 - sqrt(5))) / (-1 - sqrt(5))) == 1 + assert expand_mul(sech(asech(-sqrt(6) - sqrt(2))) / (-sqrt(6) - sqrt(2))) == 1 + + # numerical evaluation + assert str(asech(5*I).n(6)) == '0.19869 - 1.5708*I' + assert str(asech(-5*I).n(6)) == '0.19869 + 1.5708*I' + + +def test_asech_leading_term(): + x = Symbol('x') + # Tests concerning branch points + assert asech(x).as_leading_term(x, cdir=1) == -log(x) + log(2) + assert asech(x).as_leading_term(x, cdir=-1) == -log(x) + log(2) + 2*I*pi + assert asech(x + 1).as_leading_term(x, cdir=1) == sqrt(2)*I*sqrt(x) + assert asech(1/x).as_leading_term(x, cdir=1) == I*pi/2 + # Tests concerning points lying on branch cuts + assert asech(x - 1).as_leading_term(x, cdir=1) == I*pi + assert asech(I*x + 3).as_leading_term(x, cdir=1) == -asech(3) + assert asech(-I*x + 3).as_leading_term(x, cdir=1) == asech(3) + assert asech(I*x - 3).as_leading_term(x, cdir=1) == -asech(-3) + assert asech(-I*x - 3).as_leading_term(x, cdir=1) == asech(-3) + assert asech(I*x - S(1)/3).as_leading_term(x, cdir=1) == -2*I*pi + asech(-S(1)/3) + assert asech(I*x - S(1)/3).as_leading_term(x, cdir=-1) == asech(-S(1)/3) + # Tests concerning im(ndir) == 0 + assert asech(-I*x**2 + x - 3).as_leading_term(x, cdir=1) == log(-S(1)/3 + 2*sqrt(2)*I/3) + assert asech(-I*x**2 + x - 3).as_leading_term(x, cdir=-1) == log(-S(1)/3 + 2*sqrt(2)*I/3) + + +def test_asech_series(): + x = Symbol('x') + assert asech(x).series(x, 0, 9, cdir=1) == log(2) - log(x) - x**2/4 - 3*x**4/32 \ + - 5*x**6/96 - 35*x**8/1024 + O(x**9) + assert asech(x).series(x, 0, 9, cdir=-1) == I*pi + log(2) - log(-x) - x**2/4 - \ + 3*x**4/32 - 5*x**6/96 - 35*x**8/1024 + O(x**9) + t6 = asech(x).taylor_term(6, x) + assert t6 == -5*x**6/96 + assert asech(x).taylor_term(8, x, t6, 0) == -35*x**8/1024 + + +def test_asech_nseries(): + x = Symbol('x') + # Tests concerning branch points + assert asech(x + 1)._eval_nseries(x, 4, None) == sqrt(2)*sqrt(-x) + 5*sqrt(2)*(-x)**(S(3)/2)/12 + \ + 43*sqrt(2)*(-x)**(S(5)/2)/160 + 177*sqrt(2)*(-x)**(S(7)/2)/896 + O(x**4) + # Tests concerning points lying on branch cuts + assert asech(x - 1)._eval_nseries(x, 4, None) == I*pi + sqrt(2)*sqrt(x) + \ + 5*sqrt(2)*x**(S(3)/2)/12 + 43*sqrt(2)*x**(S(5)/2)/160 + 177*sqrt(2)*x**(S(7)/2)/896 + O(x**4) + assert asech(I*x + 3)._eval_nseries(x, 4, None) == -asech(3) + sqrt(2)*x/12 - \ + 17*sqrt(2)*I*x**2/576 - 443*sqrt(2)*x**3/41472 + O(x**4) + assert asech(-I*x + 3)._eval_nseries(x, 4, None) == asech(3) + sqrt(2)*x/12 + \ + 17*sqrt(2)*I*x**2/576 - 443*sqrt(2)*x**3/41472 + O(x**4) + assert asech(I*x - 3)._eval_nseries(x, 4, None) == -asech(-3) - sqrt(2)*x/12 - \ + 17*sqrt(2)*I*x**2/576 + 443*sqrt(2)*x**3/41472 + O(x**4) + assert asech(-I*x - 3)._eval_nseries(x, 4, None) == asech(-3) - sqrt(2)*x/12 + \ + 17*sqrt(2)*I*x**2/576 + 443*sqrt(2)*x**3/41472 + O(x**4) + # Tests concerning im(ndir) == 0 + assert asech(-I*x**2 + x - 2)._eval_nseries(x, 3, None) == 2*I*pi/3 + \ + x*(-sqrt(3) + 3*I)/(6*sqrt(3) + 6*I) + x**2*(36 + sqrt(3)*(7 - 12*I) + 21*I)/(72*sqrt(3) - \ + 72*I) + O(x**3) + + +def test_asech_rewrite(): + x = Symbol('x') + assert asech(x).rewrite(log) == log(1/x + sqrt(1/x - 1) * sqrt(1/x + 1)) + assert asech(x).rewrite(acosh) == acosh(1/x) + assert asech(x).rewrite(asinh) == sqrt(-1 + 1/x)*(I*asinh(I/x, evaluate=False) + pi/2)/sqrt(1 - 1/x) + assert asech(x).rewrite(atanh) == \ + sqrt(x + 1)*sqrt(1/(x + 1))*atanh(sqrt(1 - x**2)) + I*pi*(-sqrt(x)*sqrt(1/x) + 1 - I*sqrt(x**2)/(2*sqrt(-x**2)) - I*sqrt(-x)/(2*sqrt(x))) + + +def test_asech_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: asech(x).fdiff(2)) + + +def test_acsch(): + x = Symbol('x') + + assert unchanged(acsch, x) + assert acsch(-x) == -acsch(x) + + # values at fixed points + assert acsch(1) == log(1 + sqrt(2)) + assert acsch(-1) == - log(1 + sqrt(2)) + assert acsch(0) is zoo + assert acsch(2) == log((1+sqrt(5))/2) + assert acsch(-2) == - log((1+sqrt(5))/2) + + assert acsch(I) == - I*pi/2 + assert acsch(-I) == I*pi/2 + assert acsch(-I*(sqrt(6) + sqrt(2))) == I*pi / 12 + assert acsch(I*(sqrt(2) + sqrt(6))) == -I*pi / 12 + assert acsch(-I*(1 + sqrt(5))) == I*pi / 10 + assert acsch(I*(1 + sqrt(5))) == -I*pi / 10 + assert acsch(-I*2 / sqrt(2 - sqrt(2))) == I*pi / 8 + assert acsch(I*2 / sqrt(2 - sqrt(2))) == -I*pi / 8 + assert acsch(-I*2) == I*pi / 6 + assert acsch(I*2) == -I*pi / 6 + assert acsch(-I*sqrt(2 + 2/sqrt(5))) == I*pi / 5 + assert acsch(I*sqrt(2 + 2/sqrt(5))) == -I*pi / 5 + assert acsch(-I*sqrt(2)) == I*pi / 4 + assert acsch(I*sqrt(2)) == -I*pi / 4 + assert acsch(-I*(sqrt(5)-1)) == 3*I*pi / 10 + assert acsch(I*(sqrt(5)-1)) == -3*I*pi / 10 + assert acsch(-I*2 / sqrt(3)) == I*pi / 3 + assert acsch(I*2 / sqrt(3)) == -I*pi / 3 + assert acsch(-I*2 / sqrt(2 + sqrt(2))) == 3*I*pi / 8 + assert acsch(I*2 / sqrt(2 + sqrt(2))) == -3*I*pi / 8 + assert acsch(-I*sqrt(2 - 2/sqrt(5))) == 2*I*pi / 5 + assert acsch(I*sqrt(2 - 2/sqrt(5))) == -2*I*pi / 5 + assert acsch(-I*(sqrt(6) - sqrt(2))) == 5*I*pi / 12 + assert acsch(I*(sqrt(6) - sqrt(2))) == -5*I*pi / 12 + assert acsch(nan) is nan + + # properties + # acsch(x) == asinh(1/x) + assert acsch(-I*sqrt(2)) == asinh(I/sqrt(2)) + assert acsch(-I*2 / sqrt(3)) == asinh(I*sqrt(3) / 2) + + # reality + assert acsch(S(2)).is_real is True + assert acsch(S(2)).is_finite is True + assert acsch(S(-2)).is_real is True + assert acsch(S(oo)).is_extended_real is True + assert acsch(-S(oo)).is_real is True + assert (acsch(2) - oo) == -oo + assert acsch(symbols('y', extended_real=True)).is_extended_real is True + + # acsch(x) == -I*asin(I/x) + assert acsch(-I*sqrt(2)) == -I*asin(-1/sqrt(2)) + assert acsch(-I*2 / sqrt(3)) == -I*asin(-sqrt(3)/2) + + # csch(acsch(x)) / x == 1 + assert expand_mul(csch(acsch(-I*(sqrt(6) + sqrt(2)))) / (-I*(sqrt(6) + sqrt(2)))) == 1 + assert expand_mul(csch(acsch(I*(1 + sqrt(5)))) / (I*(1 + sqrt(5)))) == 1 + assert (csch(acsch(I*sqrt(2 - 2/sqrt(5)))) / (I*sqrt(2 - 2/sqrt(5)))).simplify() == 1 + assert (csch(acsch(-I*sqrt(2 - 2/sqrt(5)))) / (-I*sqrt(2 - 2/sqrt(5)))).simplify() == 1 + + # numerical evaluation + assert str(acsch(5*I+1).n(6)) == '0.0391819 - 0.193363*I' + assert str(acsch(-5*I+1).n(6)) == '0.0391819 + 0.193363*I' + + +def test_acsch_infinities(): + assert acsch(oo) == 0 + assert acsch(-oo) == 0 + assert acsch(zoo) == 0 + + +def test_acsch_leading_term(): + x = Symbol('x') + assert acsch(1/x).as_leading_term(x) == x + # Tests concerning branch points + assert acsch(x + I).as_leading_term(x) == -I*pi/2 + assert acsch(x - I).as_leading_term(x) == I*pi/2 + # Tests concerning points lying on branch cuts + assert acsch(x).as_leading_term(x, cdir=1) == -log(x) + log(2) + assert acsch(x).as_leading_term(x, cdir=-1) == log(x) - log(2) - I*pi + assert acsch(x + I/2).as_leading_term(x, cdir=1) == -I*pi - acsch(I/2) + assert acsch(x + I/2).as_leading_term(x, cdir=-1) == acsch(I/2) + assert acsch(x - I/2).as_leading_term(x, cdir=1) == -acsch(I/2) + assert acsch(x - I/2).as_leading_term(x, cdir=-1) == acsch(I/2) + I*pi + # Tests concerning re(ndir) == 0 + assert acsch(I/2 + I*x - x**2).as_leading_term(x, cdir=1) == log(2 - sqrt(3)) - I*pi/2 + assert acsch(I/2 + I*x - x**2).as_leading_term(x, cdir=-1) == log(2 - sqrt(3)) - I*pi/2 + + +def test_acsch_series(): + x = Symbol('x') + assert acsch(x).series(x, 0, 9) == log(2) - log(x) + x**2/4 - 3*x**4/32 \ + + 5*x**6/96 - 35*x**8/1024 + O(x**9) + t4 = acsch(x).taylor_term(4, x) + assert t4 == -3*x**4/32 + assert acsch(x).taylor_term(6, x, t4, 0) == 5*x**6/96 + + +def test_acsch_nseries(): + x = Symbol('x') + # Tests concerning branch points + assert acsch(x + I)._eval_nseries(x, 4, None) == -I*pi/2 + \ + sqrt(2)*I*sqrt(x)*sqrt(-I) - 5*x**(S(3)/2)*(1 - I)/12 - \ + 43*sqrt(2)*I*x**(S(5)/2)*sqrt(-I)/160 + 177*x**(S(7)/2)*(1 - I)/896 + O(x**4) + assert acsch(x - I)._eval_nseries(x, 4, None) == I*pi/2 - \ + sqrt(2)*sqrt(I)*I*sqrt(x) - 5*x**(S(3)/2)*(1 + I)/12 + \ + 43*sqrt(2)*sqrt(I)*I*x**(S(5)/2)/160 + 177*x**(S(7)/2)*(1 + I)/896 + O(x**4) + # Tests concerning points lying on branch cuts + assert acsch(x + I/2)._eval_nseries(x, 4, None, cdir=1) == -acsch(I/2) - \ + I*pi + 4*sqrt(3)*I*x/3 - 8*sqrt(3)*x**2/9 - 16*sqrt(3)*I*x**3/9 + O(x**4) + assert acsch(x + I/2)._eval_nseries(x, 4, None, cdir=-1) == acsch(I/2) - \ + 4*sqrt(3)*I*x/3 + 8*sqrt(3)*x**2/9 + 16*sqrt(3)*I*x**3/9 + O(x**4) + assert acsch(x - I/2)._eval_nseries(x, 4, None, cdir=1) == -acsch(I/2) - \ + 4*sqrt(3)*I*x/3 - 8*sqrt(3)*x**2/9 + 16*sqrt(3)*I*x**3/9 + O(x**4) + assert acsch(x - I/2)._eval_nseries(x, 4, None, cdir=-1) == I*pi + \ + acsch(I/2) + 4*sqrt(3)*I*x/3 + 8*sqrt(3)*x**2/9 - 16*sqrt(3)*I*x**3/9 + O(x**4) + # Tests concerning re(ndir) == 0 + assert acsch(I/2 + I*x - x**2)._eval_nseries(x, 4, None) == -I*pi/2 + \ + log(2 - sqrt(3)) + x*(12 - 8*sqrt(3))/(-6 + 3*sqrt(3)) + x**2*(-96 + \ + sqrt(3)*(56 - 84*I) + 144*I)/(-63 + 36*sqrt(3)) + x**3*(2688 - 2688*I + \ + sqrt(3)*(-1552 + 1552*I))/(-873 + 504*sqrt(3)) + O(x**4) + + +def test_acsch_rewrite(): + x = Symbol('x') + assert acsch(x).rewrite(log) == log(1/x + sqrt(1/x**2 + 1)) + assert acsch(x).rewrite(asinh) == asinh(1/x) + assert acsch(x).rewrite(atanh) == (sqrt(-x**2)*(-sqrt(-(x**2 + 1)**2) + *atanh(sqrt(x**2 + 1))/(x**2 + 1) + + pi/2)/x) + + +def test_acsch_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: acsch(x).fdiff(2)) + + +def test_atanh(): + x = Symbol('x') + + # at specific points + assert atanh(0) == 0 + assert atanh(I) == I*pi/4 + assert atanh(-I) == -I*pi/4 + assert atanh(1) is oo + assert atanh(-1) is -oo + assert atanh(nan) is nan + + # at infinites + assert atanh(oo) == -I*pi/2 + assert atanh(-oo) == I*pi/2 + + assert atanh(I*oo) == I*pi/2 + assert atanh(-I*oo) == -I*pi/2 + + assert atanh(zoo) == I*AccumBounds(-pi/2, pi/2) + + # properties + assert atanh(-x) == -atanh(x) + + # reality + assert atanh(S(2)).is_real is False + assert atanh(S(-1)/5).is_real is True + assert atanh(symbols('y', extended_real=True)).is_real is None + assert atanh(S(1)).is_real is False + assert atanh(S(1)).is_extended_real is True + assert atanh(S(-1)).is_real is False + + # special values + assert atanh(I/sqrt(3)) == I*pi/6 + assert atanh(-I/sqrt(3)) == -I*pi/6 + assert atanh(I*sqrt(3)) == I*pi/3 + assert atanh(-I*sqrt(3)) == -I*pi/3 + assert atanh(I*(1 + sqrt(2))) == pi*I*Rational(3, 8) + assert atanh(I*(sqrt(2) - 1)) == pi*I/8 + assert atanh(I*(1 - sqrt(2))) == -pi*I/8 + assert atanh(-I*(1 + sqrt(2))) == pi*I*Rational(-3, 8) + assert atanh(I*sqrt(5 + 2*sqrt(5))) == I*pi*Rational(2, 5) + assert atanh(-I*sqrt(5 + 2*sqrt(5))) == I*pi*Rational(-2, 5) + assert atanh(I*(2 - sqrt(3))) == pi*I/12 + assert atanh(I*(sqrt(3) - 2)) == -pi*I/12 + assert atanh(oo) == -I*pi/2 + + # Symmetry + assert atanh(Rational(-1, 2)) == -atanh(S.Half) + + # inverse composition + assert unchanged(atanh, tanh(Symbol('v1'))) + + assert atanh(tanh(-5, evaluate=False)) == -5 + assert atanh(tanh(0, evaluate=False)) == 0 + assert atanh(tanh(7, evaluate=False)) == 7 + assert atanh(tanh(I, evaluate=False)) == I + assert atanh(tanh(-I, evaluate=False)) == -I + assert atanh(tanh(-11*I, evaluate=False)) == -11*I + 4*I*pi + assert atanh(tanh(3 + I)) == 3 + I + assert atanh(tanh(4 + 5*I)) == 4 - 2*I*pi + 5*I + assert atanh(tanh(pi/2)) == pi/2 + assert atanh(tanh(pi)) == pi + assert atanh(tanh(-3 + 7*I)) == -3 - 2*I*pi + 7*I + assert atanh(tanh(9 - I*2/3)) == 9 - I*2/3 + assert atanh(tanh(-32 - 123*I)) == -32 - 123*I + 39*I*pi + + +def test_atanh_rewrite(): + x = Symbol('x') + assert atanh(x).rewrite(log) == (log(1 + x) - log(1 - x)) / 2 + assert atanh(x).rewrite(asinh) == \ + pi*x/(2*sqrt(-x**2)) - sqrt(-x)*sqrt(1 - x**2)*sqrt(1/(x**2 - 1))*asinh(sqrt(1/(x**2 - 1)))/sqrt(x) + + +def test_atanh_leading_term(): + x = Symbol('x') + assert atanh(x).as_leading_term(x) == x + # Tests concerning branch points + assert atanh(x + 1).as_leading_term(x, cdir=1) == -log(x)/2 + log(2)/2 - I*pi/2 + assert atanh(x + 1).as_leading_term(x, cdir=-1) == -log(x)/2 + log(2)/2 + I*pi/2 + assert atanh(x - 1).as_leading_term(x, cdir=1) == log(x)/2 - log(2)/2 + assert atanh(x - 1).as_leading_term(x, cdir=-1) == log(x)/2 - log(2)/2 + assert atanh(1/x).as_leading_term(x, cdir=1) == -I*pi/2 + assert atanh(1/x).as_leading_term(x, cdir=-1) == I*pi/2 + # Tests concerning points lying on branch cuts + assert atanh(I*x + 2).as_leading_term(x, cdir=1) == atanh(2) + I*pi + assert atanh(-I*x + 2).as_leading_term(x, cdir=1) == atanh(2) + assert atanh(I*x - 2).as_leading_term(x, cdir=1) == -atanh(2) + assert atanh(-I*x - 2).as_leading_term(x, cdir=1) == -I*pi - atanh(2) + # Tests concerning im(ndir) == 0 + assert atanh(-I*x**2 + x - 2).as_leading_term(x, cdir=1) == -log(3)/2 - I*pi/2 + assert atanh(-I*x**2 + x - 2).as_leading_term(x, cdir=-1) == -log(3)/2 - I*pi/2 + + +def test_atanh_series(): + x = Symbol('x') + assert atanh(x).series(x, 0, 10) == \ + x + x**3/3 + x**5/5 + x**7/7 + x**9/9 + O(x**10) + + +def test_atanh_nseries(): + x = Symbol('x') + # Tests concerning branch points + assert atanh(x + 1)._eval_nseries(x, 4, None, cdir=1) == -I*pi/2 + log(2)/2 - \ + log(x)/2 + x/4 - x**2/16 + x**3/48 + O(x**4) + assert atanh(x + 1)._eval_nseries(x, 4, None, cdir=-1) == I*pi/2 + log(2)/2 - \ + log(x)/2 + x/4 - x**2/16 + x**3/48 + O(x**4) + assert atanh(x - 1)._eval_nseries(x, 4, None, cdir=1) == -log(2)/2 + log(x)/2 + \ + x/4 + x**2/16 + x**3/48 + O(x**4) + assert atanh(x - 1)._eval_nseries(x, 4, None, cdir=-1) == -log(2)/2 + log(x)/2 + \ + x/4 + x**2/16 + x**3/48 + O(x**4) + # Tests concerning points lying on branch cuts + assert atanh(I*x + 2)._eval_nseries(x, 4, None, cdir=1) == I*pi + atanh(2) - \ + I*x/3 - 2*x**2/9 + 13*I*x**3/81 + O(x**4) + assert atanh(I*x + 2)._eval_nseries(x, 4, None, cdir=-1) == atanh(2) - I*x/3 - \ + 2*x**2/9 + 13*I*x**3/81 + O(x**4) + assert atanh(I*x - 2)._eval_nseries(x, 4, None, cdir=1) == -atanh(2) - I*x/3 + \ + 2*x**2/9 + 13*I*x**3/81 + O(x**4) + assert atanh(I*x - 2)._eval_nseries(x, 4, None, cdir=-1) == -atanh(2) - I*pi - \ + I*x/3 + 2*x**2/9 + 13*I*x**3/81 + O(x**4) + # Tests concerning im(ndir) == 0 + assert atanh(-I*x**2 + x - 2)._eval_nseries(x, 4, None) == -I*pi/2 - log(3)/2 - x/3 + \ + x**2*(-S(1)/4 + I/2) + x**2*(S(1)/36 - I/6) + x**3*(-S(1)/6 + I/2) + x**3*(S(1)/162 - I/18) + O(x**4) + + +def test_atanh_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: atanh(x).fdiff(2)) + + +def test_acoth(): + x = Symbol('x') + + #at specific points + assert acoth(0) == I*pi/2 + assert acoth(I) == -I*pi/4 + assert acoth(-I) == I*pi/4 + assert acoth(1) is oo + assert acoth(-1) is -oo + assert acoth(nan) is nan + + # at infinites + assert acoth(oo) == 0 + assert acoth(-oo) == 0 + assert acoth(I*oo) == 0 + assert acoth(-I*oo) == 0 + assert acoth(zoo) == 0 + + #properties + assert acoth(-x) == -acoth(x) + + assert acoth(I/sqrt(3)) == -I*pi/3 + assert acoth(-I/sqrt(3)) == I*pi/3 + assert acoth(I*sqrt(3)) == -I*pi/6 + assert acoth(-I*sqrt(3)) == I*pi/6 + assert acoth(I*(1 + sqrt(2))) == -pi*I/8 + assert acoth(-I*(sqrt(2) + 1)) == pi*I/8 + assert acoth(I*(1 - sqrt(2))) == pi*I*Rational(3, 8) + assert acoth(I*(sqrt(2) - 1)) == pi*I*Rational(-3, 8) + assert acoth(I*sqrt(5 + 2*sqrt(5))) == -I*pi/10 + assert acoth(-I*sqrt(5 + 2*sqrt(5))) == I*pi/10 + assert acoth(I*(2 + sqrt(3))) == -pi*I/12 + assert acoth(-I*(2 + sqrt(3))) == pi*I/12 + assert acoth(I*(2 - sqrt(3))) == pi*I*Rational(-5, 12) + assert acoth(I*(sqrt(3) - 2)) == pi*I*Rational(5, 12) + + # reality + assert acoth(S(2)).is_real is True + assert acoth(S(2)).is_finite is True + assert acoth(S(2)).is_extended_real is True + assert acoth(S(-2)).is_real is True + assert acoth(S(1)).is_real is False + assert acoth(S(1)).is_extended_real is True + assert acoth(S(-1)).is_real is False + assert acoth(symbols('y', real=True)).is_real is None + + # Symmetry + assert acoth(Rational(-1, 2)) == -acoth(S.Half) + + +def test_acoth_rewrite(): + x = Symbol('x') + assert acoth(x).rewrite(log) == (log(1 + 1/x) - log(1 - 1/x)) / 2 + assert acoth(x).rewrite(atanh) == atanh(1/x) + assert acoth(x).rewrite(asinh) == \ + x*sqrt(x**(-2))*asinh(sqrt(1/(x**2 - 1))) + I*pi*(sqrt((x - 1)/x)*sqrt(x/(x - 1)) - sqrt(x/(x + 1))*sqrt(1 + 1/x))/2 + + +def test_acoth_leading_term(): + x = Symbol('x') + # Tests concerning branch points + assert acoth(x + 1).as_leading_term(x, cdir=1) == -log(x)/2 + log(2)/2 + assert acoth(x + 1).as_leading_term(x, cdir=-1) == -log(x)/2 + log(2)/2 + assert acoth(x - 1).as_leading_term(x, cdir=1) == log(x)/2 - log(2)/2 + I*pi/2 + assert acoth(x - 1).as_leading_term(x, cdir=-1) == log(x)/2 - log(2)/2 - I*pi/2 + # Tests concerning points lying on branch cuts + assert acoth(x).as_leading_term(x, cdir=-1) == I*pi/2 + assert acoth(x).as_leading_term(x, cdir=1) == -I*pi/2 + assert acoth(I*x + 1/2).as_leading_term(x, cdir=1) == acoth(1/2) + assert acoth(-I*x + 1/2).as_leading_term(x, cdir=1) == acoth(1/2) + I*pi + assert acoth(I*x - 1/2).as_leading_term(x, cdir=1) == -I*pi - acoth(1/2) + assert acoth(-I*x - 1/2).as_leading_term(x, cdir=1) == -acoth(1/2) + # Tests concerning im(ndir) == 0 + assert acoth(-I*x**2 - x - S(1)/2).as_leading_term(x, cdir=1) == -log(3)/2 + I*pi/2 + assert acoth(-I*x**2 - x - S(1)/2).as_leading_term(x, cdir=-1) == -log(3)/2 + I*pi/2 + + +def test_acoth_series(): + x = Symbol('x') + assert acoth(x).series(x, 0, 10) == \ + -I*pi/2 + x + x**3/3 + x**5/5 + x**7/7 + x**9/9 + O(x**10) + + +def test_acoth_nseries(): + x = Symbol('x') + # Tests concerning branch points + assert acoth(x + 1)._eval_nseries(x, 4, None) == log(2)/2 - log(x)/2 + x/4 - \ + x**2/16 + x**3/48 + O(x**4) + assert acoth(x - 1)._eval_nseries(x, 4, None, cdir=1) == I*pi/2 - log(2)/2 + \ + log(x)/2 + x/4 + x**2/16 + x**3/48 + O(x**4) + assert acoth(x - 1)._eval_nseries(x, 4, None, cdir=-1) == -I*pi/2 - log(2)/2 + \ + log(x)/2 + x/4 + x**2/16 + x**3/48 + O(x**4) + # Tests concerning points lying on branch cuts + assert acoth(I*x + S(1)/2)._eval_nseries(x, 4, None, cdir=1) == acoth(S(1)/2) + \ + 4*I*x/3 - 8*x**2/9 - 112*I*x**3/81 + O(x**4) + assert acoth(I*x + S(1)/2)._eval_nseries(x, 4, None, cdir=-1) == I*pi + \ + acoth(S(1)/2) + 4*I*x/3 - 8*x**2/9 - 112*I*x**3/81 + O(x**4) + assert acoth(I*x - S(1)/2)._eval_nseries(x, 4, None, cdir=1) == -acoth(S(1)/2) - \ + I*pi + 4*I*x/3 + 8*x**2/9 - 112*I*x**3/81 + O(x**4) + assert acoth(I*x - S(1)/2)._eval_nseries(x, 4, None, cdir=-1) == -acoth(S(1)/2) + \ + 4*I*x/3 + 8*x**2/9 - 112*I*x**3/81 + O(x**4) + # Tests concerning im(ndir) == 0 + assert acoth(-I*x**2 - x - S(1)/2)._eval_nseries(x, 4, None) == I*pi/2 - log(3)/2 - \ + 4*x/3 + x**2*(-S(8)/9 + 2*I/3) - 2*I*x**2 + x**3*(S(104)/81 - 16*I/9) - 8*x**3/3 + O(x**4) + + +def test_acoth_fdiff(): + x = Symbol('x') + raises(ArgumentIndexError, lambda: acoth(x).fdiff(2)) + + +def test_inverses(): + x = Symbol('x') + assert sinh(x).inverse() == asinh + raises(AttributeError, lambda: cosh(x).inverse()) + assert tanh(x).inverse() == atanh + assert coth(x).inverse() == acoth + assert asinh(x).inverse() == sinh + assert acosh(x).inverse() == cosh + assert atanh(x).inverse() == tanh + assert acoth(x).inverse() == coth + assert asech(x).inverse() == sech + assert acsch(x).inverse() == csch + + +def test_leading_term(): + x = Symbol('x') + assert cosh(x).as_leading_term(x) == 1 + assert coth(x).as_leading_term(x) == 1/x + for func in [sinh, tanh]: + assert func(x).as_leading_term(x) == x + for func in [sinh, cosh, tanh, coth]: + for ar in (1/x, S.Half): + eq = func(ar) + assert eq.as_leading_term(x) == eq + for func in [csch, sech]: + eq = func(S.Half) + assert eq.as_leading_term(x) == eq + + +def test_complex(): + a, b = symbols('a,b', real=True) + z = a + b*I + for func in [sinh, cosh, tanh, coth, sech, csch]: + assert func(z).conjugate() == func(a - b*I) + for deep in [True, False]: + assert sinh(z).expand( + complex=True, deep=deep) == sinh(a)*cos(b) + I*cosh(a)*sin(b) + assert cosh(z).expand( + complex=True, deep=deep) == cosh(a)*cos(b) + I*sinh(a)*sin(b) + assert tanh(z).expand(complex=True, deep=deep) == sinh(a)*cosh( + a)/(cos(b)**2 + sinh(a)**2) + I*sin(b)*cos(b)/(cos(b)**2 + sinh(a)**2) + assert coth(z).expand(complex=True, deep=deep) == sinh(a)*cosh( + a)/(sin(b)**2 + sinh(a)**2) - I*sin(b)*cos(b)/(sin(b)**2 + sinh(a)**2) + assert csch(z).expand(complex=True, deep=deep) == cos(b) * sinh(a) / (sin(b)**2\ + *cosh(a)**2 + cos(b)**2 * sinh(a)**2) - I*sin(b) * cosh(a) / (sin(b)**2\ + *cosh(a)**2 + cos(b)**2 * sinh(a)**2) + assert sech(z).expand(complex=True, deep=deep) == cos(b) * cosh(a) / (sin(b)**2\ + *sinh(a)**2 + cos(b)**2 * cosh(a)**2) - I*sin(b) * sinh(a) / (sin(b)**2\ + *sinh(a)**2 + cos(b)**2 * cosh(a)**2) + + +def test_complex_2899(): + a, b = symbols('a,b', real=True) + for deep in [True, False]: + for func in [sinh, cosh, tanh, coth]: + assert func(a).expand(complex=True, deep=deep) == func(a) + + +def test_simplifications(): + x = Symbol('x') + assert sinh(asinh(x)) == x + assert sinh(acosh(x)) == sqrt(x - 1) * sqrt(x + 1) + assert sinh(atanh(x)) == x/sqrt(1 - x**2) + assert sinh(acoth(x)) == 1/(sqrt(x - 1) * sqrt(x + 1)) + + assert cosh(asinh(x)) == sqrt(1 + x**2) + assert cosh(acosh(x)) == x + assert cosh(atanh(x)) == 1/sqrt(1 - x**2) + assert cosh(acoth(x)) == x/(sqrt(x - 1) * sqrt(x + 1)) + + assert tanh(asinh(x)) == x/sqrt(1 + x**2) + assert tanh(acosh(x)) == sqrt(x - 1) * sqrt(x + 1) / x + assert tanh(atanh(x)) == x + assert tanh(acoth(x)) == 1/x + + assert coth(asinh(x)) == sqrt(1 + x**2)/x + assert coth(acosh(x)) == x/(sqrt(x - 1) * sqrt(x + 1)) + assert coth(atanh(x)) == 1/x + assert coth(acoth(x)) == x + + assert csch(asinh(x)) == 1/x + assert csch(acosh(x)) == 1/(sqrt(x - 1) * sqrt(x + 1)) + assert csch(atanh(x)) == sqrt(1 - x**2)/x + assert csch(acoth(x)) == sqrt(x - 1) * sqrt(x + 1) + + assert sech(asinh(x)) == 1/sqrt(1 + x**2) + assert sech(acosh(x)) == 1/x + assert sech(atanh(x)) == sqrt(1 - x**2) + assert sech(acoth(x)) == sqrt(x - 1) * sqrt(x + 1)/x + + +def test_issue_4136(): + assert cosh(asinh(Integer(3)/2)) == sqrt(Integer(13)/4) + + +def test_sinh_rewrite(): + x = Symbol('x') + assert sinh(x).rewrite(exp) == (exp(x) - exp(-x))/2 \ + == sinh(x).rewrite('tractable') + assert sinh(x).rewrite(cosh) == -I*cosh(x + I*pi/2) + tanh_half = tanh(S.Half*x) + assert sinh(x).rewrite(tanh) == 2*tanh_half/(1 - tanh_half**2) + coth_half = coth(S.Half*x) + assert sinh(x).rewrite(coth) == 2*coth_half/(coth_half**2 - 1) + + +def test_cosh_rewrite(): + x = Symbol('x') + assert cosh(x).rewrite(exp) == (exp(x) + exp(-x))/2 \ + == cosh(x).rewrite('tractable') + assert cosh(x).rewrite(sinh) == -I*sinh(x + I*pi/2, evaluate=False) + tanh_half = tanh(S.Half*x)**2 + assert cosh(x).rewrite(tanh) == (1 + tanh_half)/(1 - tanh_half) + coth_half = coth(S.Half*x)**2 + assert cosh(x).rewrite(coth) == (coth_half + 1)/(coth_half - 1) + + +def test_tanh_rewrite(): + x = Symbol('x') + assert tanh(x).rewrite(exp) == (exp(x) - exp(-x))/(exp(x) + exp(-x)) \ + == tanh(x).rewrite('tractable') + assert tanh(x).rewrite(sinh) == I*sinh(x)/sinh(I*pi/2 - x, evaluate=False) + assert tanh(x).rewrite(cosh) == I*cosh(I*pi/2 - x, evaluate=False)/cosh(x) + assert tanh(x).rewrite(coth) == 1/coth(x) + + +def test_coth_rewrite(): + x = Symbol('x') + assert coth(x).rewrite(exp) == (exp(x) + exp(-x))/(exp(x) - exp(-x)) \ + == coth(x).rewrite('tractable') + assert coth(x).rewrite(sinh) == -I*sinh(I*pi/2 - x, evaluate=False)/sinh(x) + assert coth(x).rewrite(cosh) == -I*cosh(x)/cosh(I*pi/2 - x, evaluate=False) + assert coth(x).rewrite(tanh) == 1/tanh(x) + + +def test_csch_rewrite(): + x = Symbol('x') + assert csch(x).rewrite(exp) == 1 / (exp(x)/2 - exp(-x)/2) \ + == csch(x).rewrite('tractable') + assert csch(x).rewrite(cosh) == I/cosh(x + I*pi/2, evaluate=False) + tanh_half = tanh(S.Half*x) + assert csch(x).rewrite(tanh) == (1 - tanh_half**2)/(2*tanh_half) + coth_half = coth(S.Half*x) + assert csch(x).rewrite(coth) == (coth_half**2 - 1)/(2*coth_half) + + +def test_sech_rewrite(): + x = Symbol('x') + assert sech(x).rewrite(exp) == 1 / (exp(x)/2 + exp(-x)/2) \ + == sech(x).rewrite('tractable') + assert sech(x).rewrite(sinh) == I/sinh(x + I*pi/2, evaluate=False) + tanh_half = tanh(S.Half*x)**2 + assert sech(x).rewrite(tanh) == (1 - tanh_half)/(1 + tanh_half) + coth_half = coth(S.Half*x)**2 + assert sech(x).rewrite(coth) == (coth_half - 1)/(coth_half + 1) + + +def test_derivs(): + x = Symbol('x') + assert coth(x).diff(x) == -sinh(x)**(-2) + assert sinh(x).diff(x) == cosh(x) + assert cosh(x).diff(x) == sinh(x) + assert tanh(x).diff(x) == -tanh(x)**2 + 1 + assert csch(x).diff(x) == -coth(x)*csch(x) + assert sech(x).diff(x) == -tanh(x)*sech(x) + assert acoth(x).diff(x) == 1/(-x**2 + 1) + assert asinh(x).diff(x) == 1/sqrt(x**2 + 1) + assert acosh(x).diff(x) == 1/(sqrt(x - 1)*sqrt(x + 1)) + assert acosh(x).diff(x) == acosh(x).rewrite(log).diff(x).together() + assert atanh(x).diff(x) == 1/(-x**2 + 1) + assert asech(x).diff(x) == -1/(x*sqrt(1 - x**2)) + assert acsch(x).diff(x) == -1/(x**2*sqrt(1 + x**(-2))) + + +def test_sinh_expansion(): + x, y = symbols('x,y') + assert sinh(x+y).expand(trig=True) == sinh(x)*cosh(y) + cosh(x)*sinh(y) + assert sinh(2*x).expand(trig=True) == 2*sinh(x)*cosh(x) + assert sinh(3*x).expand(trig=True).expand() == \ + sinh(x)**3 + 3*sinh(x)*cosh(x)**2 + + +def test_cosh_expansion(): + x, y = symbols('x,y') + assert cosh(x+y).expand(trig=True) == cosh(x)*cosh(y) + sinh(x)*sinh(y) + assert cosh(2*x).expand(trig=True) == cosh(x)**2 + sinh(x)**2 + assert cosh(3*x).expand(trig=True).expand() == \ + 3*sinh(x)**2*cosh(x) + cosh(x)**3 + +def test_cosh_positive(): + # See issue 11721 + # cosh(x) is positive for real values of x + k = symbols('k', real=True) + n = symbols('n', integer=True) + + assert cosh(k, evaluate=False).is_positive is True + assert cosh(k + 2*n*pi*I, evaluate=False).is_positive is True + assert cosh(I*pi/4, evaluate=False).is_positive is True + assert cosh(3*I*pi/4, evaluate=False).is_positive is False + +def test_cosh_nonnegative(): + k = symbols('k', real=True) + n = symbols('n', integer=True) + + assert cosh(k, evaluate=False).is_nonnegative is True + assert cosh(k + 2*n*pi*I, evaluate=False).is_nonnegative is True + assert cosh(I*pi/4, evaluate=False).is_nonnegative is True + assert cosh(3*I*pi/4, evaluate=False).is_nonnegative is False + assert cosh(S.Zero, evaluate=False).is_nonnegative is True + +def test_real_assumptions(): + z = Symbol('z', real=False) + assert sinh(z).is_real is None + assert cosh(z).is_real is None + assert tanh(z).is_real is None + assert sech(z).is_real is None + assert csch(z).is_real is None + assert coth(z).is_real is None + +def test_sign_assumptions(): + p = Symbol('p', positive=True) + n = Symbol('n', negative=True) + assert sinh(n).is_negative is True + assert sinh(p).is_positive is True + assert cosh(n).is_positive is True + assert cosh(p).is_positive is True + assert tanh(n).is_negative is True + assert tanh(p).is_positive is True + assert csch(n).is_negative is True + assert csch(p).is_positive is True + assert sech(n).is_positive is True + assert sech(p).is_positive is True + assert coth(n).is_negative is True + assert coth(p).is_positive is True + + +def test_issue_25847(): + x = Symbol('x') + + #atanh + assert atanh(sin(x)/x).as_leading_term(x) == atanh(sin(x)/x) + raises(PoleError, lambda: atanh(exp(1/x)).as_leading_term(x)) + + #asinh + assert asinh(sin(x)/x).as_leading_term(x) == log(1 + sqrt(2)) + raises(PoleError, lambda: asinh(exp(1/x)).as_leading_term(x)) + + #acosh + assert acosh(sin(x)/x).as_leading_term(x) == 0 + raises(PoleError, lambda: acosh(exp(1/x)).as_leading_term(x)) + + #acoth + assert acoth(sin(x)/x).as_leading_term(x) == acoth(sin(x)/x) + raises(PoleError, lambda: acoth(exp(1/x)).as_leading_term(x)) + + #asech + assert asech(sinh(x)/x).as_leading_term(x) == 0 + raises(PoleError, lambda: asech(exp(1/x)).as_leading_term(x)) + + #acsch + assert acsch(sin(x)/x).as_leading_term(x) == log(1 + sqrt(2)) + raises(PoleError, lambda: acsch(exp(1/x)).as_leading_term(x)) + + +def test_issue_25175(): + x = Symbol('x') + g1 = 2*acosh(1 + 2*x/3) - acosh(S(5)/3 - S(8)/3/(x + 4)) + g2 = 2*log(sqrt((x + 4)/3)*(sqrt(x + 3)+sqrt(x))**2/(2*sqrt(x + 3) + sqrt(x))) + assert (g1 - g2).series(x) == O(x**6) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_integers.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_integers.py new file mode 100644 index 0000000000000000000000000000000000000000..a48ad2ac24c4a857d57b2f24e3308ac90078a9b1 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_integers.py @@ -0,0 +1,688 @@ +from sympy.calculus.accumulationbounds import AccumBounds +from sympy.core.numbers import (E, Float, I, Rational, Integer, nan, oo, pi, zoo) +from sympy.core.relational import (Eq, Ge, Gt, Le, Lt, Ne) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.combinatorial.factorials import factorial +from sympy.functions.elementary.exponential import (exp, log) +from sympy.functions.elementary.integers import (ceiling, floor, frac) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import sin, cos, tan, asin +from sympy.polys.rootoftools import RootOf, CRootOf +from sympy import Integers +from sympy.sets.sets import Interval +from sympy.sets.fancysets import ImageSet +from sympy.core.function import Lambda + +from sympy.core.expr import unchanged +from sympy.testing.pytest import XFAIL, raises + +x = Symbol('x') +i = Symbol('i', imaginary=True) +y = Symbol('y', real=True) +k, n = symbols('k,n', integer=True) +b = Symbol('b', real=True, noninteger=True) +m = Symbol('m', positive=True) + + +def test_floor(): + + assert floor(nan) is nan + + assert floor(oo) is oo + assert floor(-oo) is -oo + assert floor(zoo) is zoo + + assert floor(0) == 0 + + assert floor(1) == 1 + assert floor(-1) == -1 + + assert floor(I*log(asin(5)/abs(asin(5)))) == 0 + assert floor(-I*log(asin(7)/abs(asin(7)))) == -2 + + assert floor(E) == 2 + assert floor(-E) == -3 + + assert floor(2*E) == 5 + assert floor(-2*E) == -6 + + assert floor(pi) == 3 + assert floor(-pi) == -4 + + assert floor(S.Half) == 0 + assert floor(Rational(-1, 2)) == -1 + + assert floor(Rational(7, 3)) == 2 + assert floor(Rational(-7, 3)) == -3 + assert floor(-Rational(7, 3)) == -3 + + assert floor(Float(17.0)) == 17 + assert floor(-Float(17.0)) == -17 + + assert floor(Float(7.69)) == 7 + assert floor(-Float(7.69)) == -8 + + assert floor(1/(m+1)) == S.Zero + assert floor((m+2)/(m+1)) == S.One + assert floor(-1/(m+1)) == S.NegativeOne + assert floor((m+2)/(-m-1)) == Integer(-2) + + assert floor(I) == I + assert floor(-I) == -I + e = floor(i) + assert e.func is floor and e.args[0] == i + + assert floor(oo*I) == oo*I + assert floor(-oo*I) == -oo*I + assert floor(exp(I*pi/4)*oo) == exp(I*pi/4)*oo + + assert floor(2*I) == 2*I + assert floor(-2*I) == -2*I + + assert floor(I/2) == 0 + assert floor(-I/2) == -I + + assert floor(E + 17) == 19 + assert floor(pi + 2) == 5 + + assert floor(E + pi) == 5 + assert floor(I + pi) == 3 + I + + assert floor(floor(pi)) == 3 + assert floor(floor(y)) == floor(y) + assert floor(floor(x)) == floor(x) + + assert unchanged(floor, x) + assert unchanged(floor, 2*x) + assert unchanged(floor, k*x) + + assert floor(k) == k + assert floor(2*k) == 2*k + assert floor(k*n) == k*n + + assert unchanged(floor, k/2) + + assert unchanged(floor, x + y) + + assert floor(x + 3) == floor(x) + 3 + assert floor(x + k) == floor(x) + k + + assert floor(y + 3) == floor(y) + 3 + assert floor(y + k) == floor(y) + k + + assert floor(3 + I*y + pi) == 6 + floor(y)*I + + assert floor(k + n) == k + n + + assert unchanged(floor, x*I) + assert floor(k*I) == k*I + + assert floor(Rational(23, 10) - E*I) == 2 - 3*I + + assert floor(sin(1)) == 0 + assert floor(sin(-1)) == -1 + + assert floor(exp(2)) == 7 + + assert floor(log(8)/log(2)) != 2 + assert int(floor(log(8)/log(2)).evalf(chop=True)) == 3 + + assert floor(factorial(50)/exp(1)) == \ + 11188719610782480504630258070757734324011354208865721592720336800 + + assert (floor(y) < y).is_Relational + assert (floor(y) <= y) == True + assert (floor(y) > y) == False + assert (floor(y) >= y).is_Relational + assert (floor(x) <= x).is_Relational # x could be non-real + assert (floor(x) > x).is_Relational + assert (floor(x) <= y).is_Relational # arg is not same as rhs + assert (floor(x) > y).is_Relational + assert (floor(y) <= oo) == True + assert (floor(y) < oo) == True + assert (floor(y) >= -oo) == True + assert (floor(y) > -oo) == True + assert (floor(b) < b) == True + assert (floor(b) <= b) == True + assert (floor(b) > b) == False + assert (floor(b) >= b) == False + + assert floor(y).rewrite(frac) == y - frac(y) + assert floor(y).rewrite(ceiling) == -ceiling(-y) + assert floor(y).rewrite(frac).subs(y, -pi) == floor(-pi) + assert floor(y).rewrite(frac).subs(y, E) == floor(E) + assert floor(y).rewrite(ceiling).subs(y, E) == -ceiling(-E) + assert floor(y).rewrite(ceiling).subs(y, -pi) == -ceiling(pi) + + assert Eq(floor(y), y - frac(y)) + assert Eq(floor(y), -ceiling(-y)) + + neg = Symbol('neg', negative=True) + nn = Symbol('nn', nonnegative=True) + pos = Symbol('pos', positive=True) + np = Symbol('np', nonpositive=True) + + assert (floor(neg) < 0) == True + assert (floor(neg) <= 0) == True + assert (floor(neg) > 0) == False + assert (floor(neg) >= 0) == False + assert (floor(neg) <= -1) == True + assert (floor(neg) >= -3) == (neg >= -3) + assert (floor(neg) < 5) == (neg < 5) + + assert (floor(nn) < 0) == False + assert (floor(nn) >= 0) == True + + assert (floor(pos) < 0) == False + assert (floor(pos) <= 0) == (pos < 1) + assert (floor(pos) > 0) == (pos >= 1) + assert (floor(pos) >= 0) == True + assert (floor(pos) >= 3) == (pos >= 3) + + assert (floor(np) <= 0) == True + assert (floor(np) > 0) == False + + assert floor(neg).is_negative == True + assert floor(neg).is_nonnegative == False + assert floor(nn).is_negative == False + assert floor(nn).is_nonnegative == True + assert floor(pos).is_negative == False + assert floor(pos).is_nonnegative == True + assert floor(np).is_negative is None + assert floor(np).is_nonnegative is None + + assert (floor(7, evaluate=False) >= 7) == True + assert (floor(7, evaluate=False) > 7) == False + assert (floor(7, evaluate=False) <= 7) == True + assert (floor(7, evaluate=False) < 7) == False + + assert (floor(7, evaluate=False) >= 6) == True + assert (floor(7, evaluate=False) > 6) == True + assert (floor(7, evaluate=False) <= 6) == False + assert (floor(7, evaluate=False) < 6) == False + + assert (floor(7, evaluate=False) >= 8) == False + assert (floor(7, evaluate=False) > 8) == False + assert (floor(7, evaluate=False) <= 8) == True + assert (floor(7, evaluate=False) < 8) == True + + assert (floor(x) <= 5.5) == Le(floor(x), 5.5, evaluate=False) + assert (floor(x) >= -3.2) == Ge(floor(x), -3.2, evaluate=False) + assert (floor(x) < 2.9) == Lt(floor(x), 2.9, evaluate=False) + assert (floor(x) > -1.7) == Gt(floor(x), -1.7, evaluate=False) + + assert (floor(y) <= 5.5) == (y < 6) + assert (floor(y) >= -3.2) == (y >= -3) + assert (floor(y) < 2.9) == (y < 3) + assert (floor(y) > -1.7) == (y >= -1) + + assert (floor(y) <= n) == (y < n + 1) + assert (floor(y) >= n) == (y >= n) + assert (floor(y) < n) == (y < n) + assert (floor(y) > n) == (y >= n + 1) + + assert floor(RootOf(x**3 - 27*x, 2)) == 5 + + +def test_ceiling(): + + assert ceiling(nan) is nan + + assert ceiling(oo) is oo + assert ceiling(-oo) is -oo + assert ceiling(zoo) is zoo + + assert ceiling(0) == 0 + + assert ceiling(1) == 1 + assert ceiling(-1) == -1 + + assert ceiling(I*log(asin(5)/abs(asin(5)))) == 1 + assert ceiling(-I*log(asin(7)/abs(asin(7)))) == -1 + + assert ceiling(E) == 3 + assert ceiling(-E) == -2 + + assert ceiling(2*E) == 6 + assert ceiling(-2*E) == -5 + + assert ceiling(pi) == 4 + assert ceiling(-pi) == -3 + + assert ceiling(S.Half) == 1 + assert ceiling(Rational(-1, 2)) == 0 + + assert ceiling(Rational(7, 3)) == 3 + assert ceiling(-Rational(7, 3)) == -2 + + assert ceiling(Float(17.0)) == 17 + assert ceiling(-Float(17.0)) == -17 + + assert ceiling(Float(7.69)) == 8 + assert ceiling(-Float(7.69)) == -7 + + assert ceiling(1/(m+1)) == S.One + assert ceiling((m+2)/(m+1)) == Integer(2) + assert ceiling(-1/(m+1)) == S.Zero + assert ceiling((m+2)/(-m-1)) == S.NegativeOne + + assert ceiling(I) == I + assert ceiling(-I) == -I + e = ceiling(i) + assert e.func is ceiling and e.args[0] == i + + assert ceiling(oo*I) == oo*I + assert ceiling(-oo*I) == -oo*I + assert ceiling(exp(I*pi/4)*oo) == exp(I*pi/4)*oo + + assert ceiling(2*I) == 2*I + assert ceiling(-2*I) == -2*I + + assert ceiling(I/2) == I + assert ceiling(-I/2) == 0 + + assert ceiling(E + 17) == 20 + assert ceiling(pi + 2) == 6 + + assert ceiling(E + pi) == 6 + assert ceiling(I + pi) == I + 4 + + assert ceiling(ceiling(pi)) == 4 + assert ceiling(ceiling(y)) == ceiling(y) + assert ceiling(ceiling(x)) == ceiling(x) + + assert unchanged(ceiling, x) + assert unchanged(ceiling, 2*x) + assert unchanged(ceiling, k*x) + + assert ceiling(k) == k + assert ceiling(2*k) == 2*k + assert ceiling(k*n) == k*n + + assert unchanged(ceiling, k/2) + + assert unchanged(ceiling, x + y) + + assert ceiling(x + 3) == ceiling(x) + 3 + assert ceiling(x + 3.0) == ceiling(x) + 3 + assert ceiling(x + 3.0*I) == ceiling(x) + 3*I + assert ceiling(x + k) == ceiling(x) + k + + assert ceiling(y + 3) == ceiling(y) + 3 + assert ceiling(y + k) == ceiling(y) + k + + assert ceiling(3 + pi + y*I) == 7 + ceiling(y)*I + + assert ceiling(k + n) == k + n + + assert unchanged(ceiling, x*I) + assert ceiling(k*I) == k*I + + assert ceiling(Rational(23, 10) - E*I) == 3 - 2*I + + assert ceiling(sin(1)) == 1 + assert ceiling(sin(-1)) == 0 + + assert ceiling(exp(2)) == 8 + + assert ceiling(-log(8)/log(2)) != -2 + assert int(ceiling(-log(8)/log(2)).evalf(chop=True)) == -3 + + assert ceiling(factorial(50)/exp(1)) == \ + 11188719610782480504630258070757734324011354208865721592720336801 + + assert (ceiling(y) >= y) == True + assert (ceiling(y) > y).is_Relational + assert (ceiling(y) < y) == False + assert (ceiling(y) <= y).is_Relational + assert (ceiling(x) >= x).is_Relational # x could be non-real + assert (ceiling(x) < x).is_Relational + assert (ceiling(x) >= y).is_Relational # arg is not same as rhs + assert (ceiling(x) < y).is_Relational + assert (ceiling(y) >= -oo) == True + assert (ceiling(y) > -oo) == True + assert (ceiling(y) <= oo) == True + assert (ceiling(y) < oo) == True + assert (ceiling(b) < b) == False + assert (ceiling(b) <= b) == False + assert (ceiling(b) > b) == True + assert (ceiling(b) >= b) == True + + assert ceiling(y).rewrite(floor) == -floor(-y) + assert ceiling(y).rewrite(frac) == y + frac(-y) + assert ceiling(y).rewrite(floor).subs(y, -pi) == -floor(pi) + assert ceiling(y).rewrite(floor).subs(y, E) == -floor(-E) + assert ceiling(y).rewrite(frac).subs(y, pi) == ceiling(pi) + assert ceiling(y).rewrite(frac).subs(y, -E) == ceiling(-E) + + assert Eq(ceiling(y), y + frac(-y)) + assert Eq(ceiling(y), -floor(-y)) + + neg = Symbol('neg', negative=True) + nn = Symbol('nn', nonnegative=True) + pos = Symbol('pos', positive=True) + np = Symbol('np', nonpositive=True) + + assert (ceiling(neg) <= 0) == True + assert (ceiling(neg) < 0) == (neg <= -1) + assert (ceiling(neg) > 0) == False + assert (ceiling(neg) >= 0) == (neg > -1) + assert (ceiling(neg) > -3) == (neg > -3) + assert (ceiling(neg) <= 10) == (neg <= 10) + + assert (ceiling(nn) < 0) == False + assert (ceiling(nn) >= 0) == True + + assert (ceiling(pos) < 0) == False + assert (ceiling(pos) <= 0) == False + assert (ceiling(pos) > 0) == True + assert (ceiling(pos) >= 0) == True + assert (ceiling(pos) >= 1) == True + assert (ceiling(pos) > 5) == (pos > 5) + + assert (ceiling(np) <= 0) == True + assert (ceiling(np) > 0) == False + + assert ceiling(neg).is_positive == False + assert ceiling(neg).is_nonpositive == True + assert ceiling(nn).is_positive is None + assert ceiling(nn).is_nonpositive is None + assert ceiling(pos).is_positive == True + assert ceiling(pos).is_nonpositive == False + assert ceiling(np).is_positive == False + assert ceiling(np).is_nonpositive == True + + assert (ceiling(7, evaluate=False) >= 7) == True + assert (ceiling(7, evaluate=False) > 7) == False + assert (ceiling(7, evaluate=False) <= 7) == True + assert (ceiling(7, evaluate=False) < 7) == False + + assert (ceiling(7, evaluate=False) >= 6) == True + assert (ceiling(7, evaluate=False) > 6) == True + assert (ceiling(7, evaluate=False) <= 6) == False + assert (ceiling(7, evaluate=False) < 6) == False + + assert (ceiling(7, evaluate=False) >= 8) == False + assert (ceiling(7, evaluate=False) > 8) == False + assert (ceiling(7, evaluate=False) <= 8) == True + assert (ceiling(7, evaluate=False) < 8) == True + + assert (ceiling(x) <= 5.5) == Le(ceiling(x), 5.5, evaluate=False) + assert (ceiling(x) >= -3.2) == Ge(ceiling(x), -3.2, evaluate=False) + assert (ceiling(x) < 2.9) == Lt(ceiling(x), 2.9, evaluate=False) + assert (ceiling(x) > -1.7) == Gt(ceiling(x), -1.7, evaluate=False) + + assert (ceiling(y) <= 5.5) == (y <= 5) + assert (ceiling(y) >= -3.2) == (y > -4) + assert (ceiling(y) < 2.9) == (y <= 2) + assert (ceiling(y) > -1.7) == (y > -2) + + assert (ceiling(y) <= n) == (y <= n) + assert (ceiling(y) >= n) == (y > n - 1) + assert (ceiling(y) < n) == (y <= n - 1) + assert (ceiling(y) > n) == (y > n) + + assert ceiling(RootOf(x**3 - 27*x, 2)) == 6 + s = ImageSet(Lambda(n, n + (CRootOf(x**5 - x**2 + 1, 0))), Integers) + f = CRootOf(x**5 - x**2 + 1, 0) + s = ImageSet(Lambda(n, n + f), Integers) + assert s.intersect(Interval(-10, 10)) == {i + f for i in range(-9, 11)} + + +def test_frac(): + assert isinstance(frac(x), frac) + assert frac(oo) == AccumBounds(0, 1) + assert frac(-oo) == AccumBounds(0, 1) + assert frac(zoo) is nan + + assert frac(n) == 0 + assert frac(nan) is nan + assert frac(Rational(4, 3)) == Rational(1, 3) + assert frac(-Rational(4, 3)) == Rational(2, 3) + assert frac(Rational(-4, 3)) == Rational(2, 3) + + r = Symbol('r', real=True) + assert frac(I*r) == I*frac(r) + assert frac(1 + I*r) == I*frac(r) + assert frac(0.5 + I*r) == 0.5 + I*frac(r) + assert frac(n + I*r) == I*frac(r) + assert frac(n + I*k) == 0 + assert unchanged(frac, x + I*x) + assert frac(x + I*n) == frac(x) + + assert frac(x).rewrite(floor) == x - floor(x) + assert frac(x).rewrite(ceiling) == x + ceiling(-x) + assert frac(y).rewrite(floor).subs(y, pi) == frac(pi) + assert frac(y).rewrite(floor).subs(y, -E) == frac(-E) + assert frac(y).rewrite(ceiling).subs(y, -pi) == frac(-pi) + assert frac(y).rewrite(ceiling).subs(y, E) == frac(E) + + assert Eq(frac(y), y - floor(y)) + assert Eq(frac(y), y + ceiling(-y)) + + r = Symbol('r', real=True) + p_i = Symbol('p_i', integer=True, positive=True) + n_i = Symbol('p_i', integer=True, negative=True) + np_i = Symbol('np_i', integer=True, nonpositive=True) + nn_i = Symbol('nn_i', integer=True, nonnegative=True) + p_r = Symbol('p_r', positive=True) + n_r = Symbol('n_r', negative=True) + np_r = Symbol('np_r', real=True, nonpositive=True) + nn_r = Symbol('nn_r', real=True, nonnegative=True) + + # Real frac argument, integer rhs + assert frac(r) <= p_i + assert not frac(r) <= n_i + assert (frac(r) <= np_i).has(Le) + assert (frac(r) <= nn_i).has(Le) + assert frac(r) < p_i + assert not frac(r) < n_i + assert not frac(r) < np_i + assert (frac(r) < nn_i).has(Lt) + assert not frac(r) >= p_i + assert frac(r) >= n_i + assert frac(r) >= np_i + assert (frac(r) >= nn_i).has(Ge) + assert not frac(r) > p_i + assert frac(r) > n_i + assert (frac(r) > np_i).has(Gt) + assert (frac(r) > nn_i).has(Gt) + + assert not Eq(frac(r), p_i) + assert not Eq(frac(r), n_i) + assert Eq(frac(r), np_i).has(Eq) + assert Eq(frac(r), nn_i).has(Eq) + + assert Ne(frac(r), p_i) + assert Ne(frac(r), n_i) + assert Ne(frac(r), np_i).has(Ne) + assert Ne(frac(r), nn_i).has(Ne) + + + # Real frac argument, real rhs + assert (frac(r) <= p_r).has(Le) + assert not frac(r) <= n_r + assert (frac(r) <= np_r).has(Le) + assert (frac(r) <= nn_r).has(Le) + assert (frac(r) < p_r).has(Lt) + assert not frac(r) < n_r + assert not frac(r) < np_r + assert (frac(r) < nn_r).has(Lt) + assert (frac(r) >= p_r).has(Ge) + assert frac(r) >= n_r + assert frac(r) >= np_r + assert (frac(r) >= nn_r).has(Ge) + assert (frac(r) > p_r).has(Gt) + assert frac(r) > n_r + assert (frac(r) > np_r).has(Gt) + assert (frac(r) > nn_r).has(Gt) + + assert not Eq(frac(r), n_r) + assert Eq(frac(r), p_r).has(Eq) + assert Eq(frac(r), np_r).has(Eq) + assert Eq(frac(r), nn_r).has(Eq) + + assert Ne(frac(r), p_r).has(Ne) + assert Ne(frac(r), n_r) + assert Ne(frac(r), np_r).has(Ne) + assert Ne(frac(r), nn_r).has(Ne) + + # Real frac argument, +/- oo rhs + assert frac(r) < oo + assert frac(r) <= oo + assert not frac(r) > oo + assert not frac(r) >= oo + + assert not frac(r) < -oo + assert not frac(r) <= -oo + assert frac(r) > -oo + assert frac(r) >= -oo + + assert frac(r) < 1 + assert frac(r) <= 1 + assert not frac(r) > 1 + assert not frac(r) >= 1 + + assert not frac(r) < 0 + assert (frac(r) <= 0).has(Le) + assert (frac(r) > 0).has(Gt) + assert frac(r) >= 0 + + # Some test for numbers + assert frac(r) <= sqrt(2) + assert (frac(r) <= sqrt(3) - sqrt(2)).has(Le) + assert not frac(r) <= sqrt(2) - sqrt(3) + assert not frac(r) >= sqrt(2) + assert (frac(r) >= sqrt(3) - sqrt(2)).has(Ge) + assert frac(r) >= sqrt(2) - sqrt(3) + + assert not Eq(frac(r), sqrt(2)) + assert Eq(frac(r), sqrt(3) - sqrt(2)).has(Eq) + assert not Eq(frac(r), sqrt(2) - sqrt(3)) + assert Ne(frac(r), sqrt(2)) + assert Ne(frac(r), sqrt(3) - sqrt(2)).has(Ne) + assert Ne(frac(r), sqrt(2) - sqrt(3)) + + assert frac(p_i, evaluate=False).is_zero + assert frac(p_i, evaluate=False).is_finite + assert frac(p_i, evaluate=False).is_integer + assert frac(p_i, evaluate=False).is_real + assert frac(r).is_finite + assert frac(r).is_real + assert frac(r).is_zero is None + assert frac(r).is_integer is None + + assert frac(oo).is_finite + assert frac(oo).is_real + + +def test_series(): + x, y = symbols('x,y') + assert floor(x).nseries(x, y, 100) == floor(y) + assert ceiling(x).nseries(x, y, 100) == ceiling(y) + assert floor(x).nseries(x, pi, 100) == 3 + assert ceiling(x).nseries(x, pi, 100) == 4 + assert floor(x).nseries(x, 0, 100) == 0 + assert ceiling(x).nseries(x, 0, 100) == 1 + assert floor(-x).nseries(x, 0, 100) == -1 + assert ceiling(-x).nseries(x, 0, 100) == 0 + + +def test_issue_14355(): + # This test checks the leading term and series for the floor and ceil + # function when arg0 evaluates to S.NaN. + assert floor((x**3 + x)/(x**2 - x)).as_leading_term(x, cdir = 1) == -2 + assert floor((x**3 + x)/(x**2 - x)).as_leading_term(x, cdir = -1) == -1 + assert floor((cos(x) - 1)/x).as_leading_term(x, cdir = 1) == -1 + assert floor((cos(x) - 1)/x).as_leading_term(x, cdir = -1) == 0 + assert floor(sin(x)/x).as_leading_term(x, cdir = 1) == 0 + assert floor(sin(x)/x).as_leading_term(x, cdir = -1) == 0 + assert floor(-tan(x)/x).as_leading_term(x, cdir = 1) == -2 + assert floor(-tan(x)/x).as_leading_term(x, cdir = -1) == -2 + assert floor(sin(x)/x/3).as_leading_term(x, cdir = 1) == 0 + assert floor(sin(x)/x/3).as_leading_term(x, cdir = -1) == 0 + assert ceiling((x**3 + x)/(x**2 - x)).as_leading_term(x, cdir = 1) == -1 + assert ceiling((x**3 + x)/(x**2 - x)).as_leading_term(x, cdir = -1) == 0 + assert ceiling((cos(x) - 1)/x).as_leading_term(x, cdir = 1) == 0 + assert ceiling((cos(x) - 1)/x).as_leading_term(x, cdir = -1) == 1 + assert ceiling(sin(x)/x).as_leading_term(x, cdir = 1) == 1 + assert ceiling(sin(x)/x).as_leading_term(x, cdir = -1) == 1 + assert ceiling(-tan(x)/x).as_leading_term(x, cdir = 1) == -1 + assert ceiling(-tan(x)/x).as_leading_term(x, cdir = 1) == -1 + assert ceiling(sin(x)/x/3).as_leading_term(x, cdir = 1) == 1 + assert ceiling(sin(x)/x/3).as_leading_term(x, cdir = -1) == 1 + # test for series + assert floor(sin(x)/x).series(x, 0, 100, cdir = 1) == 0 + assert floor(sin(x)/x).series(x, 0, 100, cdir = 1) == 0 + assert floor((x**3 + x)/(x**2 - x)).series(x, 0, 100, cdir = 1) == -2 + assert floor((x**3 + x)/(x**2 - x)).series(x, 0, 100, cdir = -1) == -1 + assert ceiling(sin(x)/x).series(x, 0, 100, cdir = 1) == 1 + assert ceiling(sin(x)/x).series(x, 0, 100, cdir = -1) == 1 + assert ceiling((x**3 + x)/(x**2 - x)).series(x, 0, 100, cdir = 1) == -1 + assert ceiling((x**3 + x)/(x**2 - x)).series(x, 0, 100, cdir = -1) == 0 + + +def test_frac_leading_term(): + assert frac(x).as_leading_term(x) == x + assert frac(x).as_leading_term(x, cdir = 1) == x + assert frac(x).as_leading_term(x, cdir = -1) == 1 + assert frac(x + S.Half).as_leading_term(x, cdir = 1) == S.Half + assert frac(x + S.Half).as_leading_term(x, cdir = -1) == S.Half + assert frac(-2*x + 1).as_leading_term(x, cdir = 1) == S.One + assert frac(-2*x + 1).as_leading_term(x, cdir = -1) == -2*x + assert frac(sin(x) + 5).as_leading_term(x, cdir = 1) == x + assert frac(sin(x) + 5).as_leading_term(x, cdir = -1) == S.One + assert frac(sin(x**2) + 5).as_leading_term(x, cdir = 1) == x**2 + assert frac(sin(x**2) + 5).as_leading_term(x, cdir = -1) == x**2 + + +@XFAIL +def test_issue_4149(): + assert floor(3 + pi*I + y*I) == 3 + floor(pi + y)*I + assert floor(3*I + pi*I + y*I) == floor(3 + pi + y)*I + assert floor(3 + E + pi*I + y*I) == 5 + floor(pi + y)*I + + +def test_issue_21651(): + k = Symbol('k', positive=True, integer=True) + exp = 2*2**(-k) + assert isinstance(floor(exp), floor) + + +def test_issue_11207(): + assert floor(floor(x)) == floor(x) + assert floor(ceiling(x)) == ceiling(x) + assert ceiling(floor(x)) == floor(x) + assert ceiling(ceiling(x)) == ceiling(x) + + +def test_nested_floor_ceiling(): + assert floor(-floor(ceiling(x**3)/y)) == -floor(ceiling(x**3)/y) + assert ceiling(-floor(ceiling(x**3)/y)) == -floor(ceiling(x**3)/y) + assert floor(ceiling(-floor(x**Rational(7, 2)/y))) == -floor(x**Rational(7, 2)/y) + assert -ceiling(-ceiling(floor(x)/y)) == ceiling(floor(x)/y) + +def test_issue_18689(): + assert floor(floor(floor(x)) + 3) == floor(x) + 3 + assert ceiling(ceiling(ceiling(x)) + 1) == ceiling(x) + 1 + assert ceiling(ceiling(floor(x)) + 3) == floor(x) + 3 + +def test_issue_18421(): + assert floor(float(0)) is S.Zero + assert ceiling(float(0)) is S.Zero + +def test_issue_25230(): + a = Symbol('a', real = True) + b = Symbol('b', positive = True) + c = Symbol('c', negative = True) + raises(NotImplementedError, lambda: floor(x/a).as_leading_term(x, cdir = 1)) + raises(NotImplementedError, lambda: ceiling(x/a).as_leading_term(x, cdir = 1)) + assert floor(x/b).as_leading_term(x, cdir = 1) == 0 + assert floor(x/b).as_leading_term(x, cdir = -1) == -1 + assert floor(x/c).as_leading_term(x, cdir = 1) == -1 + assert floor(x/c).as_leading_term(x, cdir = -1) == 0 + assert ceiling(x/b).as_leading_term(x, cdir = 1) == 1 + assert ceiling(x/b).as_leading_term(x, cdir = -1) == 0 + assert ceiling(x/c).as_leading_term(x, cdir = 1) == 0 + assert ceiling(x/c).as_leading_term(x, cdir = -1) == 1 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_interface.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_interface.py new file mode 100644 index 0000000000000000000000000000000000000000..6ae2f78b50bea24c64079066076971e315660d69 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_interface.py @@ -0,0 +1,82 @@ +# This test file tests the SymPy function interface, that people use to create +# their own new functions. It should be as easy as possible. +# +# We test that it works with both Function and DefinedFunction. New code should +# use DefinedFunction because it has better type inference. Old code still +# using Function should continue to work though. +from sympy.core.function import Function, DefinedFunction +from sympy.core.sympify import sympify +from sympy.functions.elementary.hyperbolic import tanh +from sympy.functions.elementary.trigonometric import (cos, sin) +from sympy.series.limits import limit +from sympy.abc import x + + +def test_function_series1(): + """Create our new "sin" function.""" + + for F in [Function, DefinedFunction]: + + class my_function(F): + + def fdiff(self, argindex=1): + return cos(self.args[0]) + + @classmethod + def eval(cls, arg): + arg = sympify(arg) + if arg == 0: + return sympify(0) + + #Test that the taylor series is correct + assert my_function(x).series(x, 0, 10) == sin(x).series(x, 0, 10) + assert limit(my_function(x)/x, x, 0) == 1 + + +def test_function_series2(): + """Create our new "cos" function.""" + + for F in [Function, DefinedFunction]: + + class my_function2(F): + + def fdiff(self, argindex=1): + return -sin(self.args[0]) + + @classmethod + def eval(cls, arg): + arg = sympify(arg) + if arg == 0: + return sympify(1) + + #Test that the taylor series is correct + assert my_function2(x).series(x, 0, 10) == cos(x).series(x, 0, 10) + + +def test_function_series3(): + """ + Test our easy "tanh" function. + + This test tests two things: + * that the Function interface works as expected and it's easy to use + * that the general algorithm for the series expansion works even when the + derivative is defined recursively in terms of the original function, + since tanh(x).diff(x) == 1-tanh(x)**2 + """ + + for F in [Function, DefinedFunction]: + + class mytanh(F): + + def fdiff(self, argindex=1): + return 1 - mytanh(self.args[0])**2 + + @classmethod + def eval(cls, arg): + arg = sympify(arg) + if arg == 0: + return sympify(0) + + e = tanh(x) + f = mytanh(x) + assert e.series(x, 0, 6) == f.series(x, 0, 6) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_miscellaneous.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_miscellaneous.py new file mode 100644 index 0000000000000000000000000000000000000000..374c4fb50eaae54a9884015c124c245385e1761e --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_miscellaneous.py @@ -0,0 +1,504 @@ +import itertools as it + +from sympy.core.expr import unchanged +from sympy.core.function import Function +from sympy.core.numbers import I, oo, Rational +from sympy.core.power import Pow +from sympy.core.singleton import S +from sympy.core.symbol import Symbol +from sympy.external import import_module +from sympy.functions.elementary.exponential import log +from sympy.functions.elementary.integers import floor, ceiling +from sympy.functions.elementary.miscellaneous import (sqrt, cbrt, root, Min, + Max, real_root, Rem) +from sympy.functions.elementary.trigonometric import cos, sin +from sympy.functions.special.delta_functions import Heaviside + +from sympy.utilities.lambdify import lambdify +from sympy.testing.pytest import raises, skip, ignore_warnings + +def test_Min(): + from sympy.abc import x, y, z + n = Symbol('n', negative=True) + n_ = Symbol('n_', negative=True) + nn = Symbol('nn', nonnegative=True) + nn_ = Symbol('nn_', nonnegative=True) + p = Symbol('p', positive=True) + p_ = Symbol('p_', positive=True) + np = Symbol('np', nonpositive=True) + np_ = Symbol('np_', nonpositive=True) + r = Symbol('r', real=True) + + assert Min(5, 4) == 4 + assert Min(-oo, -oo) is -oo + assert Min(-oo, n) is -oo + assert Min(n, -oo) is -oo + assert Min(-oo, np) is -oo + assert Min(np, -oo) is -oo + assert Min(-oo, 0) is -oo + assert Min(0, -oo) is -oo + assert Min(-oo, nn) is -oo + assert Min(nn, -oo) is -oo + assert Min(-oo, p) is -oo + assert Min(p, -oo) is -oo + assert Min(-oo, oo) is -oo + assert Min(oo, -oo) is -oo + assert Min(n, n) == n + assert unchanged(Min, n, np) + assert Min(np, n) == Min(n, np) + assert Min(n, 0) == n + assert Min(0, n) == n + assert Min(n, nn) == n + assert Min(nn, n) == n + assert Min(n, p) == n + assert Min(p, n) == n + assert Min(n, oo) == n + assert Min(oo, n) == n + assert Min(np, np) == np + assert Min(np, 0) == np + assert Min(0, np) == np + assert Min(np, nn) == np + assert Min(nn, np) == np + assert Min(np, p) == np + assert Min(p, np) == np + assert Min(np, oo) == np + assert Min(oo, np) == np + assert Min(0, 0) == 0 + assert Min(0, nn) == 0 + assert Min(nn, 0) == 0 + assert Min(0, p) == 0 + assert Min(p, 0) == 0 + assert Min(0, oo) == 0 + assert Min(oo, 0) == 0 + assert Min(nn, nn) == nn + assert unchanged(Min, nn, p) + assert Min(p, nn) == Min(nn, p) + assert Min(nn, oo) == nn + assert Min(oo, nn) == nn + assert Min(p, p) == p + assert Min(p, oo) == p + assert Min(oo, p) == p + assert Min(oo, oo) is oo + + assert Min(n, n_).func is Min + assert Min(nn, nn_).func is Min + assert Min(np, np_).func is Min + assert Min(p, p_).func is Min + + # lists + assert Min() is S.Infinity + assert Min(x) == x + assert Min(x, y) == Min(y, x) + assert Min(x, y, z) == Min(z, y, x) + assert Min(x, Min(y, z)) == Min(z, y, x) + assert Min(x, Max(y, -oo)) == Min(x, y) + assert Min(p, oo, n, p, p, p_) == n + assert Min(p_, n_, p) == n_ + assert Min(n, oo, -7, p, p, 2) == Min(n, -7) + assert Min(2, x, p, n, oo, n_, p, 2, -2, -2) == Min(-2, x, n, n_) + assert Min(0, x, 1, y) == Min(0, x, y) + assert Min(1000, 100, -100, x, p, n) == Min(n, x, -100) + assert unchanged(Min, sin(x), cos(x)) + assert Min(sin(x), cos(x)) == Min(cos(x), sin(x)) + assert Min(cos(x), sin(x)).subs(x, 1) == cos(1) + assert Min(cos(x), sin(x)).subs(x, S.Half) == sin(S.Half) + raises(ValueError, lambda: Min(cos(x), sin(x)).subs(x, I)) + raises(ValueError, lambda: Min(I)) + raises(ValueError, lambda: Min(I, x)) + raises(ValueError, lambda: Min(S.ComplexInfinity, x)) + + assert Min(1, x).diff(x) == Heaviside(1 - x) + assert Min(x, 1).diff(x) == Heaviside(1 - x) + assert Min(0, -x, 1 - 2*x).diff(x) == -Heaviside(x + Min(0, -2*x + 1)) \ + - 2*Heaviside(2*x + Min(0, -x) - 1) + + # issue 7619 + f = Function('f') + assert Min(1, 2*Min(f(1), 2)) # doesn't fail + + # issue 7233 + e = Min(0, x) + assert e.n().args == (0, x) + + # issue 8643 + m = Min(n, p_, n_, r) + assert m.is_positive is False + assert m.is_nonnegative is False + assert m.is_negative is True + + m = Min(p, p_) + assert m.is_positive is True + assert m.is_nonnegative is True + assert m.is_negative is False + + m = Min(p, nn_, p_) + assert m.is_positive is None + assert m.is_nonnegative is True + assert m.is_negative is False + + m = Min(nn, p, r) + assert m.is_positive is None + assert m.is_nonnegative is None + assert m.is_negative is None + + +def test_Max(): + from sympy.abc import x, y, z + n = Symbol('n', negative=True) + n_ = Symbol('n_', negative=True) + nn = Symbol('nn', nonnegative=True) + p = Symbol('p', positive=True) + p_ = Symbol('p_', positive=True) + r = Symbol('r', real=True) + + assert Max(5, 4) == 5 + + # lists + + assert Max() is S.NegativeInfinity + assert Max(x) == x + assert Max(x, y) == Max(y, x) + assert Max(x, y, z) == Max(z, y, x) + assert Max(x, Max(y, z)) == Max(z, y, x) + assert Max(x, Min(y, oo)) == Max(x, y) + assert Max(n, -oo, n_, p, 2) == Max(p, 2) + assert Max(n, -oo, n_, p) == p + assert Max(2, x, p, n, -oo, S.NegativeInfinity, n_, p, 2) == Max(2, x, p) + assert Max(0, x, 1, y) == Max(1, x, y) + assert Max(r, r + 1, r - 1) == 1 + r + assert Max(1000, 100, -100, x, p, n) == Max(p, x, 1000) + assert Max(cos(x), sin(x)) == Max(sin(x), cos(x)) + assert Max(cos(x), sin(x)).subs(x, 1) == sin(1) + assert Max(cos(x), sin(x)).subs(x, S.Half) == cos(S.Half) + raises(ValueError, lambda: Max(cos(x), sin(x)).subs(x, I)) + raises(ValueError, lambda: Max(I)) + raises(ValueError, lambda: Max(I, x)) + raises(ValueError, lambda: Max(S.ComplexInfinity, 1)) + assert Max(n, -oo, n_, p, 2) == Max(p, 2) + assert Max(n, -oo, n_, p, 1000) == Max(p, 1000) + + assert Max(1, x).diff(x) == Heaviside(x - 1) + assert Max(x, 1).diff(x) == Heaviside(x - 1) + assert Max(x**2, 1 + x, 1).diff(x) == \ + 2*x*Heaviside(x**2 - Max(1, x + 1)) \ + + Heaviside(x - Max(1, x**2) + 1) + + e = Max(0, x) + assert e.n().args == (0, x) + + # issue 8643 + m = Max(p, p_, n, r) + assert m.is_positive is True + assert m.is_nonnegative is True + assert m.is_negative is False + + m = Max(n, n_) + assert m.is_positive is False + assert m.is_nonnegative is False + assert m.is_negative is True + + m = Max(n, n_, r) + assert m.is_positive is None + assert m.is_nonnegative is None + assert m.is_negative is None + + m = Max(n, nn, r) + assert m.is_positive is None + assert m.is_nonnegative is True + assert m.is_negative is False + + +def test_minmax_assumptions(): + r = Symbol('r', real=True) + a = Symbol('a', real=True, algebraic=True) + t = Symbol('t', real=True, transcendental=True) + q = Symbol('q', rational=True) + p = Symbol('p', irrational=True) + n = Symbol('n', rational=True, integer=False) + i = Symbol('i', integer=True) + o = Symbol('o', odd=True) + e = Symbol('e', even=True) + k = Symbol('k', prime=True) + reals = [r, a, t, q, p, n, i, o, e, k] + + for ext in (Max, Min): + for x, y in it.product(reals, repeat=2): + + # Must be real + assert ext(x, y).is_real + + # Algebraic? + if x.is_algebraic and y.is_algebraic: + assert ext(x, y).is_algebraic + elif x.is_transcendental and y.is_transcendental: + assert ext(x, y).is_transcendental + else: + assert ext(x, y).is_algebraic is None + + # Rational? + if x.is_rational and y.is_rational: + assert ext(x, y).is_rational + elif x.is_irrational and y.is_irrational: + assert ext(x, y).is_irrational + else: + assert ext(x, y).is_rational is None + + # Integer? + if x.is_integer and y.is_integer: + assert ext(x, y).is_integer + elif x.is_noninteger and y.is_noninteger: + assert ext(x, y).is_noninteger + else: + assert ext(x, y).is_integer is None + + # Odd? + if x.is_odd and y.is_odd: + assert ext(x, y).is_odd + elif x.is_odd is False and y.is_odd is False: + assert ext(x, y).is_odd is False + else: + assert ext(x, y).is_odd is None + + # Even? + if x.is_even and y.is_even: + assert ext(x, y).is_even + elif x.is_even is False and y.is_even is False: + assert ext(x, y).is_even is False + else: + assert ext(x, y).is_even is None + + # Prime? + if x.is_prime and y.is_prime: + assert ext(x, y).is_prime + elif x.is_prime is False and y.is_prime is False: + assert ext(x, y).is_prime is False + else: + assert ext(x, y).is_prime is None + + +def test_issue_8413(): + x = Symbol('x', real=True) + # we can't evaluate in general because non-reals are not + # comparable: Min(floor(3.2 + I), 3.2 + I) -> ValueError + assert Min(floor(x), x) == floor(x) + assert Min(ceiling(x), x) == x + assert Max(floor(x), x) == x + assert Max(ceiling(x), x) == ceiling(x) + + +def test_root(): + from sympy.abc import x + n = Symbol('n', integer=True) + k = Symbol('k', integer=True) + + assert root(2, 2) == sqrt(2) + assert root(2, 1) == 2 + assert root(2, 3) == 2**Rational(1, 3) + assert root(2, 3) == cbrt(2) + assert root(2, -5) == 2**Rational(4, 5)/2 + + assert root(-2, 1) == -2 + + assert root(-2, 2) == sqrt(2)*I + assert root(-2, 1) == -2 + + assert root(x, 2) == sqrt(x) + assert root(x, 1) == x + assert root(x, 3) == x**Rational(1, 3) + assert root(x, 3) == cbrt(x) + assert root(x, -5) == x**Rational(-1, 5) + + assert root(x, n) == x**(1/n) + assert root(x, -n) == x**(-1/n) + + assert root(x, n, k) == (-1)**(2*k/n)*x**(1/n) + + +def test_real_root(): + assert real_root(-8, 3) == -2 + assert real_root(-16, 4) == root(-16, 4) + r = root(-7, 4) + assert real_root(r) == r + r1 = root(-1, 3) + r2 = r1**2 + r3 = root(-1, 4) + assert real_root(r1 + r2 + r3) == -1 + r2 + r3 + assert real_root(root(-2, 3)) == -root(2, 3) + assert real_root(-8., 3) == -2.0 + x = Symbol('x') + n = Symbol('n') + g = real_root(x, n) + assert g.subs({"x": -8, "n": 3}) == -2 + assert g.subs({"x": 8, "n": 3}) == 2 + # give principle root if there is no real root -- if this is not desired + # then maybe a Root class is needed to raise an error instead + assert g.subs({"x": I, "n": 3}) == cbrt(I) + assert g.subs({"x": -8, "n": 2}) == sqrt(-8) + assert g.subs({"x": I, "n": 2}) == sqrt(I) + + +def test_issue_11463(): + numpy = import_module('numpy') + if not numpy: + skip("numpy not installed.") + x = Symbol('x') + f = lambdify(x, real_root((log(x/(x-2))), 3), 'numpy') + # numpy.select evaluates all options before considering conditions, + # so it raises a warning about root of negative number which does + # not affect the outcome. This warning is suppressed here + with ignore_warnings(RuntimeWarning): + assert f(numpy.array(-1)) < -1 + + +def test_rewrite_MaxMin_as_Heaviside(): + from sympy.abc import x + assert Max(0, x).rewrite(Heaviside) == x*Heaviside(x) + assert Max(3, x).rewrite(Heaviside) == x*Heaviside(x - 3) + \ + 3*Heaviside(-x + 3) + assert Max(0, x+2, 2*x).rewrite(Heaviside) == \ + 2*x*Heaviside(2*x)*Heaviside(x - 2) + \ + (x + 2)*Heaviside(-x + 2)*Heaviside(x + 2) + + assert Min(0, x).rewrite(Heaviside) == x*Heaviside(-x) + assert Min(3, x).rewrite(Heaviside) == x*Heaviside(-x + 3) + \ + 3*Heaviside(x - 3) + assert Min(x, -x, -2).rewrite(Heaviside) == \ + x*Heaviside(-2*x)*Heaviside(-x - 2) - \ + x*Heaviside(2*x)*Heaviside(x - 2) \ + - 2*Heaviside(-x + 2)*Heaviside(x + 2) + + +def test_rewrite_MaxMin_as_Piecewise(): + from sympy.core.symbol import symbols + from sympy.functions.elementary.piecewise import Piecewise + x, y, z, a, b = symbols('x y z a b', real=True) + vx, vy, va = symbols('vx vy va') + assert Max(a, b).rewrite(Piecewise) == Piecewise((a, a >= b), (b, True)) + assert Max(x, y, z).rewrite(Piecewise) == Piecewise((x, (x >= y) & (x >= z)), (y, y >= z), (z, True)) + assert Max(x, y, a, b).rewrite(Piecewise) == Piecewise((a, (a >= b) & (a >= x) & (a >= y)), + (b, (b >= x) & (b >= y)), (x, x >= y), (y, True)) + assert Min(a, b).rewrite(Piecewise) == Piecewise((a, a <= b), (b, True)) + assert Min(x, y, z).rewrite(Piecewise) == Piecewise((x, (x <= y) & (x <= z)), (y, y <= z), (z, True)) + assert Min(x, y, a, b).rewrite(Piecewise) == Piecewise((a, (a <= b) & (a <= x) & (a <= y)), + (b, (b <= x) & (b <= y)), (x, x <= y), (y, True)) + + # Piecewise rewriting of Min/Max does also takes place for not explicitly real arguments + assert Max(vx, vy).rewrite(Piecewise) == Piecewise((vx, vx >= vy), (vy, True)) + assert Min(va, vx, vy).rewrite(Piecewise) == Piecewise((va, (va <= vx) & (va <= vy)), (vx, vx <= vy), (vy, True)) + + +def test_issue_11099(): + from sympy.abc import x, y + # some fixed value tests + fixed_test_data = {x: -2, y: 3} + assert Min(x, y).evalf(subs=fixed_test_data) == \ + Min(x, y).subs(fixed_test_data).evalf() + assert Max(x, y).evalf(subs=fixed_test_data) == \ + Max(x, y).subs(fixed_test_data).evalf() + # randomly generate some test data + from sympy.core.random import randint + for i in range(20): + random_test_data = {x: randint(-100, 100), y: randint(-100, 100)} + assert Min(x, y).evalf(subs=random_test_data) == \ + Min(x, y).subs(random_test_data).evalf() + assert Max(x, y).evalf(subs=random_test_data) == \ + Max(x, y).subs(random_test_data).evalf() + + +def test_issue_12638(): + from sympy.abc import a, b, c + assert Min(a, b, c, Max(a, b)) == Min(a, b, c) + assert Min(a, b, Max(a, b, c)) == Min(a, b) + assert Min(a, b, Max(a, c)) == Min(a, b) + +def test_issue_21399(): + from sympy.abc import a, b, c + assert Max(Min(a, b), Min(a, b, c)) == Min(a, b) + + +def test_instantiation_evaluation(): + from sympy.abc import v, w, x, y, z + assert Min(1, Max(2, x)) == 1 + assert Max(3, Min(2, x)) == 3 + assert Min(Max(x, y), Max(x, z)) == Max(x, Min(y, z)) + assert set(Min(Max(w, x), Max(y, z)).args) == { + Max(w, x), Max(y, z)} + assert Min(Max(x, y), Max(x, z), w) == Min( + w, Max(x, Min(y, z))) + A, B = Min, Max + for i in range(2): + assert A(x, B(x, y)) == x + assert A(x, B(y, A(x, w, z))) == A(x, B(y, A(w, z))) + A, B = B, A + assert Min(w, Max(x, y), Max(v, x, z)) == Min( + w, Max(x, Min(y, Max(v, z)))) + +def test_rewrite_as_Abs(): + from itertools import permutations + from sympy.functions.elementary.complexes import Abs + from sympy.abc import x, y, z, w + def test(e): + free = e.free_symbols + a = e.rewrite(Abs) + assert not a.has(Min, Max) + for i in permutations(range(len(free))): + reps = dict(zip(free, i)) + assert a.xreplace(reps) == e.xreplace(reps) + test(Min(x, y)) + test(Max(x, y)) + test(Min(x, y, z)) + test(Min(Max(w, x), Max(y, z))) + +def test_issue_14000(): + assert isinstance(sqrt(4, evaluate=False), Pow) == True + assert isinstance(cbrt(3.5, evaluate=False), Pow) == True + assert isinstance(root(16, 4, evaluate=False), Pow) == True + + assert sqrt(4, evaluate=False) == Pow(4, S.Half, evaluate=False) + assert cbrt(3.5, evaluate=False) == Pow(3.5, Rational(1, 3), evaluate=False) + assert root(4, 2, evaluate=False) == Pow(4, S.Half, evaluate=False) + + assert root(16, 4, 2, evaluate=False).has(Pow) == True + assert real_root(-8, 3, evaluate=False).has(Pow) == True + +def test_issue_6899(): + from sympy.core.function import Lambda + x = Symbol('x') + eqn = Lambda(x, x) + assert eqn.func(*eqn.args) == eqn + +def test_Rem(): + from sympy.abc import x, y + assert Rem(5, 3) == 2 + assert Rem(-5, 3) == -2 + assert Rem(5, -3) == 2 + assert Rem(-5, -3) == -2 + assert Rem(x**3, y) == Rem(x**3, y) + assert Rem(Rem(-5, 3) + 3, 3) == 1 + + +def test_minmax_no_evaluate(): + from sympy import evaluate + p = Symbol('p', positive=True) + + assert Max(1, 3) == 3 + assert Max(1, 3).args == () + assert Max(0, p) == p + assert Max(0, p).args == () + assert Min(0, p) == 0 + assert Min(0, p).args == () + + assert Max(1, 3, evaluate=False) != 3 + assert Max(1, 3, evaluate=False).args == (1, 3) + assert Max(0, p, evaluate=False) != p + assert Max(0, p, evaluate=False).args == (0, p) + assert Min(0, p, evaluate=False) != 0 + assert Min(0, p, evaluate=False).args == (0, p) + + with evaluate(False): + assert Max(1, 3) != 3 + assert Max(1, 3).args == (1, 3) + assert Max(0, p) != p + assert Max(0, p).args == (0, p) + assert Min(0, p) != 0 + assert Min(0, p).args == (0, p) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_piecewise.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_piecewise.py new file mode 100644 index 0000000000000000000000000000000000000000..7d0728095578b49480a1334857a1c237012d2534 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_piecewise.py @@ -0,0 +1,1639 @@ +from sympy.concrete.summations import Sum +from sympy.core.add import Add +from sympy.core.basic import Basic +from sympy.core.containers import Tuple +from sympy.core.expr import unchanged +from sympy.core.function import (Function, diff, expand) +from sympy.core.mul import Mul +from sympy.core.mod import Mod +from sympy.core.numbers import (Float, I, Rational, oo, pi, zoo) +from sympy.core.relational import (Eq, Ge, Gt, Ne) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.combinatorial.factorials import factorial +from sympy.functions.elementary.complexes import (Abs, adjoint, arg, conjugate, im, re, transpose) +from sympy.functions.elementary.exponential import (exp, log) +from sympy.functions.elementary.miscellaneous import (Max, Min, sqrt) +from sympy.functions.elementary.piecewise import (Piecewise, + piecewise_fold, piecewise_exclusive, Undefined, ExprCondPair) +from sympy.functions.elementary.trigonometric import (cos, sin) +from sympy.functions.special.delta_functions import (DiracDelta, Heaviside) +from sympy.functions.special.tensor_functions import KroneckerDelta +from sympy.integrals.integrals import (Integral, integrate) +from sympy.logic.boolalg import (And, ITE, Not, Or) +from sympy.matrices.expressions.matexpr import MatrixSymbol +from sympy.printing import srepr +from sympy.sets.contains import Contains +from sympy.sets.sets import Interval +from sympy.solvers.solvers import solve +from sympy.testing.pytest import raises, slow +from sympy.utilities.lambdify import lambdify + +a, b, c, d, x, y = symbols('a:d, x, y') +z = symbols('z', nonzero=True) + + +def test_piecewise1(): + + # Test canonicalization + assert Piecewise((x, x < 1.)).has(1.0) # doesn't get changed to x < 1 + assert unchanged(Piecewise, ExprCondPair(x, x < 1), ExprCondPair(0, True)) + assert Piecewise((x, x < 1), (0, True)) == Piecewise(ExprCondPair(x, x < 1), + ExprCondPair(0, True)) + assert Piecewise((x, x < 1), (0, True), (1, True)) == \ + Piecewise((x, x < 1), (0, True)) + assert Piecewise((x, x < 1), (0, False), (-1, 1 > 2)) == \ + Piecewise((x, x < 1)) + assert Piecewise((x, x < 1), (0, x < 1), (0, True)) == \ + Piecewise((x, x < 1), (0, True)) + assert Piecewise((x, x < 1), (0, x < 2), (0, True)) == \ + Piecewise((x, x < 1), (0, True)) + assert Piecewise((x, x < 1), (x, x < 2), (0, True)) == \ + Piecewise((x, Or(x < 1, x < 2)), (0, True)) + assert Piecewise((x, x < 1), (x, x < 2), (x, True)) == x + assert Piecewise((x, True)) == x + # Explicitly constructed empty Piecewise not accepted + raises(TypeError, lambda: Piecewise()) + # False condition is never retained + assert Piecewise((2*x, x < 0), (x, False)) == \ + Piecewise((2*x, x < 0), (x, False), evaluate=False) == \ + Piecewise((2*x, x < 0)) + assert Piecewise((x, False)) == Undefined + raises(TypeError, lambda: Piecewise(x)) + assert Piecewise((x, 1)) == x # 1 and 0 are accepted as True/False + raises(TypeError, lambda: Piecewise((x, 2))) + raises(TypeError, lambda: Piecewise((x, x**2))) + raises(TypeError, lambda: Piecewise(([1], True))) + assert Piecewise(((1, 2), True)) == Tuple(1, 2) + cond = (Piecewise((1, x < 0), (2, True)) < y) + assert Piecewise((1, cond) + ) == Piecewise((1, ITE(x < 0, y > 1, y > 2))) + + assert Piecewise((1, x > 0), (2, And(x <= 0, x > -1)) + ) == Piecewise((1, x > 0), (2, x > -1)) + assert Piecewise((1, x <= 0), (2, (x < 0) & (x > -1)) + ) == Piecewise((1, x <= 0)) + + # test for supporting Contains in Piecewise + pwise = Piecewise( + (1, And(x <= 6, x > 1, Contains(x, S.Integers))), + (0, True)) + assert pwise.subs(x, pi) == 0 + assert pwise.subs(x, 2) == 1 + assert pwise.subs(x, 7) == 0 + + # Test subs + p = Piecewise((-1, x < -1), (x**2, x < 0), (log(x), x >= 0)) + p_x2 = Piecewise((-1, x**2 < -1), (x**4, x**2 < 0), (log(x**2), x**2 >= 0)) + assert p.subs(x, x**2) == p_x2 + assert p.subs(x, -5) == -1 + assert p.subs(x, -1) == 1 + assert p.subs(x, 1) == log(1) + + # More subs tests + p2 = Piecewise((1, x < pi), (-1, x < 2*pi), (0, x > 2*pi)) + p3 = Piecewise((1, Eq(x, 0)), (1/x, True)) + p4 = Piecewise((1, Eq(x, 0)), (2, 1/x>2)) + assert p2.subs(x, 2) == 1 + assert p2.subs(x, 4) == -1 + assert p2.subs(x, 10) == 0 + assert p3.subs(x, 0.0) == 1 + assert p4.subs(x, 0.0) == 1 + + + f, g, h = symbols('f,g,h', cls=Function) + pf = Piecewise((f(x), x < -1), (f(x) + h(x) + 2, x <= 1)) + pg = Piecewise((g(x), x < -1), (g(x) + h(x) + 2, x <= 1)) + assert pg.subs(g, f) == pf + + assert Piecewise((1, Eq(x, 0)), (0, True)).subs(x, 0) == 1 + assert Piecewise((1, Eq(x, 0)), (0, True)).subs(x, 1) == 0 + assert Piecewise((1, Eq(x, y)), (0, True)).subs(x, y) == 1 + assert Piecewise((1, Eq(x, z)), (0, True)).subs(x, z) == 1 + assert Piecewise((1, Eq(exp(x), cos(z))), (0, True)).subs(x, z) == \ + Piecewise((1, Eq(exp(z), cos(z))), (0, True)) + + p5 = Piecewise( (0, Eq(cos(x) + y, 0)), (1, True)) + assert p5.subs(y, 0) == Piecewise( (0, Eq(cos(x), 0)), (1, True)) + + assert Piecewise((-1, y < 1), (0, x < 0), (1, Eq(x, 0)), (2, True) + ).subs(x, 1) == Piecewise((-1, y < 1), (2, True)) + assert Piecewise((1, Eq(x**2, -1)), (2, x < 0)).subs(x, I) == 1 + + p6 = Piecewise((x, x > 0)) + n = symbols('n', negative=True) + assert p6.subs(x, n) == Undefined + + # Test evalf + assert p.evalf() == Piecewise((-1.0, x < -1), (x**2, x < 0), (log(x), True)) + assert p.evalf(subs={x: -2}) == -1.0 + assert p.evalf(subs={x: -1}) == 1.0 + assert p.evalf(subs={x: 1}) == log(1) + assert p6.evalf(subs={x: -5}) == Undefined + + # Test doit + f_int = Piecewise((Integral(x, (x, 0, 1)), x < 1)) + assert f_int.doit() == Piecewise( (S.Half, x < 1) ) + + # Test differentiation + f = x + fp = x*p + dp = Piecewise((0, x < -1), (2*x, x < 0), (1/x, x >= 0)) + fp_dx = x*dp + p + assert diff(p, x) == dp + assert diff(f*p, x) == fp_dx + + # Test simple arithmetic + assert x*p == fp + assert x*p + p == p + x*p + assert p + f == f + p + assert p + dp == dp + p + assert p - dp == -(dp - p) + + # Test power + dp2 = Piecewise((0, x < -1), (4*x**2, x < 0), (1/x**2, x >= 0)) + assert dp**2 == dp2 + + # Test _eval_interval + f1 = x*y + 2 + f2 = x*y**2 + 3 + peval = Piecewise((f1, x < 0), (f2, x > 0)) + peval_interval = f1.subs( + x, 0) - f1.subs(x, -1) + f2.subs(x, 1) - f2.subs(x, 0) + assert peval._eval_interval(x, 0, 0) == 0 + assert peval._eval_interval(x, -1, 1) == peval_interval + peval2 = Piecewise((f1, x < 0), (f2, True)) + assert peval2._eval_interval(x, 0, 0) == 0 + assert peval2._eval_interval(x, 1, -1) == -peval_interval + assert peval2._eval_interval(x, -1, -2) == f1.subs(x, -2) - f1.subs(x, -1) + assert peval2._eval_interval(x, -1, 1) == peval_interval + assert peval2._eval_interval(x, None, 0) == peval2.subs(x, 0) + assert peval2._eval_interval(x, -1, None) == -peval2.subs(x, -1) + + # Test integration + assert p.integrate() == Piecewise( + (-x, x < -1), + (x**3/3 + Rational(4, 3), x < 0), + (x*log(x) - x + Rational(4, 3), True)) + p = Piecewise((x, x < 1), (x**2, -1 <= x), (x, 3 < x)) + assert integrate(p, (x, -2, 2)) == Rational(5, 6) + assert integrate(p, (x, 2, -2)) == Rational(-5, 6) + p = Piecewise((0, x < 0), (1, x < 1), (0, x < 2), (1, x < 3), (0, True)) + assert integrate(p, (x, -oo, oo)) == 2 + p = Piecewise((x, x < -10), (x**2, x <= -1), (x, 1 < x)) + assert integrate(p, (x, -2, 2)) == Undefined + + # Test commutativity + assert isinstance(p, Piecewise) and p.is_commutative is True + + +def test_piecewise_free_symbols(): + f = Piecewise((x, a < 0), (y, True)) + assert f.free_symbols == {x, y, a} + + +def test_piecewise_integrate1(): + x, y = symbols('x y', real=True) + + f = Piecewise(((x - 2)**2, x >= 0), (1, True)) + assert integrate(f, (x, -2, 2)) == Rational(14, 3) + + g = Piecewise(((x - 5)**5, x >= 4), (f, True)) + assert integrate(g, (x, -2, 2)) == Rational(14, 3) + assert integrate(g, (x, -2, 5)) == Rational(43, 6) + + assert g == Piecewise(((x - 5)**5, x >= 4), (f, x < 4)) + + g = Piecewise(((x - 5)**5, 2 <= x), (f, x < 2)) + assert integrate(g, (x, -2, 2)) == Rational(14, 3) + assert integrate(g, (x, -2, 5)) == Rational(-701, 6) + + assert g == Piecewise(((x - 5)**5, 2 <= x), (f, True)) + + g = Piecewise(((x - 5)**5, 2 <= x), (2*f, True)) + assert integrate(g, (x, -2, 2)) == Rational(28, 3) + assert integrate(g, (x, -2, 5)) == Rational(-673, 6) + + +def test_piecewise_integrate1b(): + g = Piecewise((1, x > 0), (0, Eq(x, 0)), (-1, x < 0)) + assert integrate(g, (x, -1, 1)) == 0 + + g = Piecewise((1, x - y < 0), (0, True)) + assert integrate(g, (y, -oo, 0)) == -Min(0, x) + assert g.subs(x, -3).integrate((y, -oo, 0)) == 3 + assert integrate(g, (y, 0, -oo)) == Min(0, x) + assert integrate(g, (y, 0, oo)) == -Max(0, x) + oo + assert integrate(g, (y, -oo, 42)) == -Min(42, x) + 42 + assert integrate(g, (y, -oo, oo)) == -x + oo + + g = Piecewise((0, x < 0), (x, x <= 1), (1, True)) + gy1 = g.integrate((x, y, 1)) + g1y = g.integrate((x, 1, y)) + for yy in (-1, S.Half, 2): + assert g.integrate((x, yy, 1)) == gy1.subs(y, yy) + assert g.integrate((x, 1, yy)) == g1y.subs(y, yy) + assert gy1 == Piecewise( + (-Min(1, Max(0, y))**2/2 + S.Half, y < 1), + (-y + 1, True)) + assert g1y == Piecewise( + (Min(1, Max(0, y))**2/2 - S.Half, y < 1), + (y - 1, True)) + + +@slow +def test_piecewise_integrate1ca(): + y = symbols('y', real=True) + g = Piecewise( + (1 - x, Interval(0, 1).contains(x)), + (1 + x, Interval(-1, 0).contains(x)), + (0, True) + ) + gy1 = g.integrate((x, y, 1)) + g1y = g.integrate((x, 1, y)) + + assert g.integrate((x, -2, 1)) == gy1.subs(y, -2) + assert g.integrate((x, 1, -2)) == g1y.subs(y, -2) + assert g.integrate((x, 0, 1)) == gy1.subs(y, 0) + assert g.integrate((x, 1, 0)) == g1y.subs(y, 0) + assert g.integrate((x, 2, 1)) == gy1.subs(y, 2) + assert g.integrate((x, 1, 2)) == g1y.subs(y, 2) + assert piecewise_fold(gy1.rewrite(Piecewise) + ).simplify() == Piecewise( + (1, y <= -1), + (-y**2/2 - y + S.Half, y <= 0), + (y**2/2 - y + S.Half, y < 1), + (0, True)) + assert piecewise_fold(g1y.rewrite(Piecewise) + ).simplify() == Piecewise( + (-1, y <= -1), + (y**2/2 + y - S.Half, y <= 0), + (-y**2/2 + y - S.Half, y < 1), + (0, True)) + assert gy1 == Piecewise( + ( + -Min(1, Max(-1, y))**2/2 - Min(1, Max(-1, y)) + + Min(1, Max(0, y))**2 + S.Half, y < 1), + (0, True) + ) + assert g1y == Piecewise( + ( + Min(1, Max(-1, y))**2/2 + Min(1, Max(-1, y)) - + Min(1, Max(0, y))**2 - S.Half, y < 1), + (0, True)) + + +@slow +def test_piecewise_integrate1cb(): + y = symbols('y', real=True) + g = Piecewise( + (0, Or(x <= -1, x >= 1)), + (1 - x, x > 0), + (1 + x, True) + ) + gy1 = g.integrate((x, y, 1)) + g1y = g.integrate((x, 1, y)) + + assert g.integrate((x, -2, 1)) == gy1.subs(y, -2) + assert g.integrate((x, 1, -2)) == g1y.subs(y, -2) + assert g.integrate((x, 0, 1)) == gy1.subs(y, 0) + assert g.integrate((x, 1, 0)) == g1y.subs(y, 0) + assert g.integrate((x, 2, 1)) == gy1.subs(y, 2) + assert g.integrate((x, 1, 2)) == g1y.subs(y, 2) + + assert piecewise_fold(gy1.rewrite(Piecewise) + ).simplify() == Piecewise( + (1, y <= -1), + (-y**2/2 - y + S.Half, y <= 0), + (y**2/2 - y + S.Half, y < 1), + (0, True)) + assert piecewise_fold(g1y.rewrite(Piecewise) + ).simplify() == Piecewise( + (-1, y <= -1), + (y**2/2 + y - S.Half, y <= 0), + (-y**2/2 + y - S.Half, y < 1), + (0, True)) + + # g1y and gy1 should simplify if the condition that y < 1 + # is applied, e.g. Min(1, Max(-1, y)) --> Max(-1, y) + assert gy1 == Piecewise( + ( + -Min(1, Max(-1, y))**2/2 - Min(1, Max(-1, y)) + + Min(1, Max(0, y))**2 + S.Half, y < 1), + (0, True) + ) + assert g1y == Piecewise( + ( + Min(1, Max(-1, y))**2/2 + Min(1, Max(-1, y)) - + Min(1, Max(0, y))**2 - S.Half, y < 1), + (0, True)) + + +def test_piecewise_integrate2(): + from itertools import permutations + lim = Tuple(x, c, d) + p = Piecewise((1, x < a), (2, x > b), (3, True)) + q = p.integrate(lim) + assert q == Piecewise( + (-c + 2*d - 2*Min(d, Max(a, c)) + Min(d, Max(a, b, c)), c < d), + (-2*c + d + 2*Min(c, Max(a, d)) - Min(c, Max(a, b, d)), True)) + for v in permutations((1, 2, 3, 4)): + r = dict(zip((a, b, c, d), v)) + assert p.subs(r).integrate(lim.subs(r)) == q.subs(r) + + +def test_meijer_bypass(): + # totally bypass meijerg machinery when dealing + # with Piecewise in integrate + assert Piecewise((1, x < 4), (0, True)).integrate((x, oo, 1)) == -3 + + +def test_piecewise_integrate3_inequality_conditions(): + from sympy.utilities.iterables import cartes + lim = (x, 0, 5) + # set below includes two pts below range, 2 pts in range, + # 2 pts above range, and the boundaries + N = (-2, -1, 0, 1, 2, 5, 6, 7) + + p = Piecewise((1, x > a), (2, x > b), (0, True)) + ans = p.integrate(lim) + for i, j in cartes(N, repeat=2): + reps = dict(zip((a, b), (i, j))) + assert ans.subs(reps) == p.subs(reps).integrate(lim) + assert ans.subs(a, 4).subs(b, 1) == 0 + 2*3 + 1 + + p = Piecewise((1, x > a), (2, x < b), (0, True)) + ans = p.integrate(lim) + for i, j in cartes(N, repeat=2): + reps = dict(zip((a, b), (i, j))) + assert ans.subs(reps) == p.subs(reps).integrate(lim) + + # delete old tests that involved c1 and c2 since those + # reduce to the above except that a value of 0 was used + # for two expressions whereas the above uses 3 different + # values + + +@slow +def test_piecewise_integrate4_symbolic_conditions(): + a = Symbol('a', real=True) + b = Symbol('b', real=True) + x = Symbol('x', real=True) + y = Symbol('y', real=True) + p0 = Piecewise((0, Or(x < a, x > b)), (1, True)) + p1 = Piecewise((0, x < a), (0, x > b), (1, True)) + p2 = Piecewise((0, x > b), (0, x < a), (1, True)) + p3 = Piecewise((0, x < a), (1, x < b), (0, True)) + p4 = Piecewise((0, x > b), (1, x > a), (0, True)) + p5 = Piecewise((1, And(a < x, x < b)), (0, True)) + + # check values of a=1, b=3 (and reversed) with values + # of y of 0, 1, 2, 3, 4 + lim = Tuple(x, -oo, y) + for p in (p0, p1, p2, p3, p4, p5): + ans = p.integrate(lim) + for i in range(5): + reps = {a:1, b:3, y:i} + assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps)) + reps = {a: 3, b:1, y:i} + assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps)) + lim = Tuple(x, y, oo) + for p in (p0, p1, p2, p3, p4, p5): + ans = p.integrate(lim) + for i in range(5): + reps = {a:1, b:3, y:i} + assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps)) + reps = {a:3, b:1, y:i} + assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps)) + + ans = Piecewise( + (0, x <= Min(a, b)), + (x - Min(a, b), x <= b), + (b - Min(a, b), True)) + for i in (p0, p1, p2, p4): + assert i.integrate(x) == ans + assert p3.integrate(x) == Piecewise( + (0, x < a), + (-a + x, x <= Max(a, b)), + (-a + Max(a, b), True)) + assert p5.integrate(x) == Piecewise( + (0, x <= a), + (-a + x, x <= Max(a, b)), + (-a + Max(a, b), True)) + + p1 = Piecewise((0, x < a), (S.Half, x > b), (1, True)) + p2 = Piecewise((S.Half, x > b), (0, x < a), (1, True)) + p3 = Piecewise((0, x < a), (1, x < b), (S.Half, True)) + p4 = Piecewise((S.Half, x > b), (1, x > a), (0, True)) + p5 = Piecewise((1, And(a < x, x < b)), (S.Half, x > b), (0, True)) + + # check values of a=1, b=3 (and reversed) with values + # of y of 0, 1, 2, 3, 4 + lim = Tuple(x, -oo, y) + for p in (p1, p2, p3, p4, p5): + ans = p.integrate(lim) + for i in range(5): + reps = {a:1, b:3, y:i} + assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps)) + reps = {a: 3, b:1, y:i} + assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps)) + + +def test_piecewise_integrate5_independent_conditions(): + p = Piecewise((0, Eq(y, 0)), (x*y, True)) + assert integrate(p, (x, 1, 3)) == Piecewise((0, Eq(y, 0)), (4*y, True)) + + +def test_issue_22917(): + p = (Piecewise((0, ITE((x - y > 1) | (2 * x - 2 * y > 1), False, + ITE(x - y > 1, 2 * y - 2 < -1, 2 * x - 2 * y > 1))), + (Piecewise((0, ITE(x - y > 1, True, 2 * x - 2 * y > 1)), + (2 * Piecewise((0, x - y > 1), (y, True)), True)), True)) + + 2 * Piecewise((1, ITE((x - y > 1) | (2 * x - 2 * y > 1), False, + ITE(x - y > 1, 2 * y - 2 < -1, 2 * x - 2 * y > 1))), + (Piecewise((1, ITE(x - y > 1, True, 2 * x - 2 * y > 1)), + (2 * Piecewise((1, x - y > 1), (x, True)), True)), True))) + assert piecewise_fold(p) == Piecewise((2, (x - y > S.Half) | (x - y > 1)), + (2*y + 4, x - y > 1), + (4*x + 2*y, True)) + assert piecewise_fold(p > 1).rewrite(ITE) == ITE((x - y > S.Half) | (x - y > 1), True, + ITE(x - y > 1, 2*y + 4 > 1, 4*x + 2*y > 1)) + + +def test_piecewise_simplify(): + p = Piecewise(((x**2 + 1)/x**2, Eq(x*(1 + x) - x**2, 0)), + ((-1)**x*(-1), True)) + assert p.simplify() == \ + Piecewise((zoo, Eq(x, 0)), ((-1)**(x + 1), True)) + # simplify when there are Eq in conditions + assert Piecewise( + (a, And(Eq(a, 0), Eq(a + b, 0))), (1, True)).simplify( + ) == Piecewise( + (0, And(Eq(a, 0), Eq(b, 0))), (1, True)) + assert Piecewise((2*x*factorial(a)/(factorial(y)*factorial(-y + a)), + Eq(y, 0) & Eq(-y + a, 0)), (2*factorial(a)/(factorial(y)*factorial(-y + + a)), Eq(y, 0) & Eq(-y + a, 1)), (0, True)).simplify( + ) == Piecewise( + (2*x, And(Eq(a, 0), Eq(y, 0))), + (2, And(Eq(a, 1), Eq(y, 0))), + (0, True)) + args = (2, And(Eq(x, 2), Ge(y, 0))), (x, True) + assert Piecewise(*args).simplify() == Piecewise(*args) + args = (1, Eq(x, 0)), (sin(x)/x, True) + assert Piecewise(*args).simplify() == Piecewise(*args) + assert Piecewise((2 + y, And(Eq(x, 2), Eq(y, 0))), (x, True) + ).simplify() == x + # check that x or f(x) are recognized as being Symbol-like for lhs + args = Tuple((1, Eq(x, 0)), (sin(x) + 1 + x, True)) + ans = x + sin(x) + 1 + f = Function('f') + assert Piecewise(*args).simplify() == ans + assert Piecewise(*args.subs(x, f(x))).simplify() == ans.subs(x, f(x)) + + # issue 18634 + d = Symbol("d", integer=True) + n = Symbol("n", integer=True) + t = Symbol("t", positive=True) + expr = Piecewise((-d + 2*n, Eq(1/t, 1)), (t**(1 - 4*n)*t**(4*n - 1)*(-d + 2*n), True)) + assert expr.simplify() == -d + 2*n + + # issue 22747 + p = Piecewise((0, (t < -2) & (t < -1) & (t < 0)), ((t/2 + 1)*(t + + 1)*(t + 2), (t < -1) & (t < 0)), ((S.Half - t/2)*(1 - t)*(t + 1), + (t < -2) & (t < -1) & (t < 1)), ((t + 1)*(-t*(t/2 + 1) + (S.Half + - t/2)*(1 - t)), (t < -2) & (t < -1) & (t < 0) & (t < 1)), ((t + + 1)*((S.Half - t/2)*(1 - t) + (t/2 + 1)*(t + 2)), (t < -1) & (t < + 1)), ((t + 1)*(-t*(t/2 + 1) + (S.Half - t/2)*(1 - t)), (t < -1) & + (t < 0) & (t < 1)), (0, (t < -2) & (t < -1)), ((t/2 + 1)*(t + + 1)*(t + 2), t < -1), ((t + 1)*(-t*(t/2 + 1) + (S.Half - t/2)*(t + + 1)), (t < 0) & ((t < -2) | (t < 0))), ((S.Half - t/2)*(1 - t)*(t + + 1), (t < 1) & ((t < -2) | (t < 1))), (0, True)) + Piecewise((0, + (t < -1) & (t < 0) & (t < 1)), ((1 - t)*(t/2 + S.Half)*(t + 1), + (t < 0) & (t < 1)), ((1 - t)*(1 - t/2)*(2 - t), (t < -1) & (t < + 0) & (t < 2)), ((1 - t)*((1 - t)*(t/2 + S.Half) + (1 - t/2)*(2 - + t)), (t < -1) & (t < 0) & (t < 1) & (t < 2)), ((1 - t)*((1 - + t/2)*(2 - t) + (t/2 + S.Half)*(t + 1)), (t < 0) & (t < 2)), ((1 - + t)*((1 - t)*(t/2 + S.Half) + (1 - t/2)*(2 - t)), (t < 0) & (t < + 1) & (t < 2)), (0, (t < -1) & (t < 0)), ((1 - t)*(t/2 + + S.Half)*(t + 1), t < 0), ((1 - t)*(t*(1 - t/2) + (1 - t)*(t/2 + + S.Half)), (t < 1) & ((t < -1) | (t < 1))), ((1 - t)*(1 - t/2)*(2 + - t), (t < 2) & ((t < -1) | (t < 2))), (0, True)) + assert p.simplify() == Piecewise( + (0, t < -2), ((t + 1)*(t + 2)**2/2, t < -1), (-3*t**3/2 + - 5*t**2/2 + 1, t < 0), (3*t**3/2 - 5*t**2/2 + 1, t < 1), ((1 - + t)*(t - 2)**2/2, t < 2), (0, True)) + + # coverage + nan = Undefined + assert Piecewise((1, x > 3), (2, x < 2), (3, x > 1)).simplify( + ) == Piecewise((1, x > 3), (2, x < 2), (3, True)) + assert Piecewise((1, x < 2), (2, x < 1), (3, True)).simplify( + ) == Piecewise((1, x < 2), (3, True)) + assert Piecewise((1, x > 2)).simplify() == Piecewise((1, x > 2), + (nan, True)) + assert Piecewise((1, (x >= 2) & (x < oo)) + ).simplify() == Piecewise((1, (x >= 2) & (x < oo)), (nan, True)) + assert Piecewise((1, x < 2), (2, (x > 1) & (x < 3)), (3, True) + ). simplify() == Piecewise((1, x < 2), (2, x < 3), (3, True)) + assert Piecewise((1, x < 2), (2, (x <= 3) & (x > 1)), (3, True) + ).simplify() == Piecewise((1, x < 2), (2, x <= 3), (3, True)) + assert Piecewise((1, x < 2), (2, (x > 2) & (x < 3)), (3, True) + ).simplify() == Piecewise((1, x < 2), (2, (x > 2) & (x < 3)), + (3, True)) + assert Piecewise((1, x < 2), (2, (x >= 1) & (x <= 3)), (3, True) + ).simplify() == Piecewise((1, x < 2), (2, x <= 3), (3, True)) + assert Piecewise((1, x < 1), (2, (x >= 2) & (x <= 3)), (3, True) + ).simplify() == Piecewise((1, x < 1), (2, (x >= 2) & (x <= 3)), + (3, True)) + # https://github.com/sympy/sympy/issues/25603 + assert Piecewise((log(x), (x <= 5) & (x > 3)), (x, True) + ).simplify() == Piecewise((log(x), (x <= 5) & (x > 3)), (x, True)) + + assert Piecewise((1, (x >= 1) & (x < 3)), (2, (x > 2) & (x < 4)) + ).simplify() == Piecewise((1, (x >= 1) & (x < 3)), ( + 2, (x >= 3) & (x < 4)), (nan, True)) + assert Piecewise((1, (x >= 1) & (x <= 3)), (2, (x > 2) & (x < 4)) + ).simplify() == Piecewise((1, (x >= 1) & (x <= 3)), ( + 2, (x > 3) & (x < 4)), (nan, True)) + + # involves a symbolic range so cset.inf fails + L = Symbol('L', nonnegative=True) + p = Piecewise((nan, x <= 0), (0, (x >= 0) & (L > x) & (L - x <= 0)), + (x - L/2, (L > x) & (L - x <= 0)), + (L/2 - x, (x >= 0) & (L > x)), + (0, L > x), (nan, True)) + assert p.simplify() == Piecewise( + (nan, x <= 0), (L/2 - x, L > x), (nan, True)) + assert p.subs(L, y).simplify() == Piecewise( + (nan, x <= 0), (-x + y/2, x < Max(0, y)), (0, x < y), (nan, True)) + + +def test_piecewise_solve(): + abs2 = Piecewise((-x, x <= 0), (x, x > 0)) + f = abs2.subs(x, x - 2) + assert solve(f, x) == [2] + assert solve(f - 1, x) == [1, 3] + + f = Piecewise(((x - 2)**2, x >= 0), (1, True)) + assert solve(f, x) == [2] + + g = Piecewise(((x - 5)**5, x >= 4), (f, True)) + assert solve(g, x) == [2, 5] + + g = Piecewise(((x - 5)**5, x >= 4), (f, x < 4)) + assert solve(g, x) == [2, 5] + + g = Piecewise(((x - 5)**5, x >= 2), (f, x < 2)) + assert solve(g, x) == [5] + + g = Piecewise(((x - 5)**5, x >= 2), (f, True)) + assert solve(g, x) == [5] + + g = Piecewise(((x - 5)**5, x >= 2), (f, True), (10, False)) + assert solve(g, x) == [5] + + g = Piecewise(((x - 5)**5, x >= 2), + (-x + 2, x - 2 <= 0), (x - 2, x - 2 > 0)) + assert solve(g, x) == [5] + + # if no symbol is given the piecewise detection must still work + assert solve(Piecewise((x - 2, x > 2), (2 - x, True)) - 3) == [-1, 5] + + f = Piecewise(((x - 2)**2, x >= 0), (0, True)) + raises(NotImplementedError, lambda: solve(f, x)) + + def nona(ans): + return list(filter(lambda x: x is not S.NaN, ans)) + p = Piecewise((x**2 - 4, x < y), (x - 2, True)) + ans = solve(p, x) + assert nona([i.subs(y, -2) for i in ans]) == [2] + assert nona([i.subs(y, 2) for i in ans]) == [-2, 2] + assert nona([i.subs(y, 3) for i in ans]) == [-2, 2] + assert ans == [ + Piecewise((-2, y > -2), (S.NaN, True)), + Piecewise((2, y <= 2), (S.NaN, True)), + Piecewise((2, y > 2), (S.NaN, True))] + + # issue 6060 + absxm3 = Piecewise( + (x - 3, 0 <= x - 3), + (3 - x, 0 > x - 3) + ) + assert solve(absxm3 - y, x) == [ + Piecewise((-y + 3, -y < 0), (S.NaN, True)), + Piecewise((y + 3, y >= 0), (S.NaN, True))] + p = Symbol('p', positive=True) + assert solve(absxm3 - p, x) == [-p + 3, p + 3] + + # issue 6989 + f = Function('f') + assert solve(Eq(-f(x), Piecewise((1, x > 0), (0, True))), f(x)) == \ + [Piecewise((-1, x > 0), (0, True))] + + # issue 8587 + f = Piecewise((2*x**2, And(0 < x, x < 1)), (2, True)) + assert solve(f - 1) == [1/sqrt(2)] + + +def test_piecewise_fold(): + p = Piecewise((x, x < 1), (1, 1 <= x)) + + assert piecewise_fold(x*p) == Piecewise((x**2, x < 1), (x, 1 <= x)) + assert piecewise_fold(p + p) == Piecewise((2*x, x < 1), (2, 1 <= x)) + assert piecewise_fold(Piecewise((1, x < 0), (2, True)) + + Piecewise((10, x < 0), (-10, True))) == \ + Piecewise((11, x < 0), (-8, True)) + + p1 = Piecewise((0, x < 0), (x, x <= 1), (0, True)) + p2 = Piecewise((0, x < 0), (1 - x, x <= 1), (0, True)) + + p = 4*p1 + 2*p2 + assert integrate( + piecewise_fold(p), (x, -oo, oo)) == integrate(2*x + 2, (x, 0, 1)) + + assert piecewise_fold( + Piecewise((1, y <= 0), (-Piecewise((2, y >= 0)), True) + )) == Piecewise((1, y <= 0), (-2, y >= 0)) + + assert piecewise_fold(Piecewise((x, ITE(x > 0, y < 1, y > 1))) + ) == Piecewise((x, ((x <= 0) | (y < 1)) & ((x > 0) | (y > 1)))) + + a, b = (Piecewise((2, Eq(x, 0)), (0, True)), + Piecewise((x, Eq(-x + y, 0)), (1, Eq(-x + y, 1)), (0, True))) + assert piecewise_fold(Mul(a, b, evaluate=False) + ) == piecewise_fold(Mul(b, a, evaluate=False)) + + +def test_piecewise_fold_piecewise_in_cond(): + p1 = Piecewise((cos(x), x < 0), (0, True)) + p2 = Piecewise((0, Eq(p1, 0)), (p1 / Abs(p1), True)) + assert p2.subs(x, -pi/2) == 0 + assert p2.subs(x, 1) == 0 + assert p2.subs(x, -pi/4) == 1 + p4 = Piecewise((0, Eq(p1, 0)), (1,True)) + ans = piecewise_fold(p4) + for i in range(-1, 1): + assert ans.subs(x, i) == p4.subs(x, i) + + r1 = 1 < Piecewise((1, x < 1), (3, True)) + ans = piecewise_fold(r1) + for i in range(2): + assert ans.subs(x, i) == r1.subs(x, i) + + p5 = Piecewise((1, x < 0), (3, True)) + p6 = Piecewise((1, x < 1), (3, True)) + p7 = Piecewise((1, p5 < p6), (0, True)) + ans = piecewise_fold(p7) + for i in range(-1, 2): + assert ans.subs(x, i) == p7.subs(x, i) + + +def test_piecewise_fold_piecewise_in_cond_2(): + p1 = Piecewise((cos(x), x < 0), (0, True)) + p2 = Piecewise((0, Eq(p1, 0)), (1 / p1, True)) + p3 = Piecewise( + (0, (x >= 0) | Eq(cos(x), 0)), + (1/cos(x), x < 0), + (zoo, True)) # redundant b/c all x are already covered + assert(piecewise_fold(p2) == p3) + + +def test_piecewise_fold_expand(): + p1 = Piecewise((1, Interval(0, 1, False, True).contains(x)), (0, True)) + + p2 = piecewise_fold(expand((1 - x)*p1)) + cond = ((x >= 0) & (x < 1)) + assert piecewise_fold(expand((1 - x)*p1), evaluate=False + ) == Piecewise((1 - x, cond), (-x, cond), (1, cond), (0, True), evaluate=False) + assert piecewise_fold(expand((1 - x)*p1), evaluate=None + ) == Piecewise((1 - x, cond), (0, True)) + assert p2 == Piecewise((1 - x, cond), (0, True)) + assert p2 == expand(piecewise_fold((1 - x)*p1)) + + +def test_piecewise_duplicate(): + p = Piecewise((x, x < -10), (x**2, x <= -1), (x, 1 < x)) + assert p == Piecewise(*p.args) + + +def test_doit(): + p1 = Piecewise((x, x < 1), (x**2, -1 <= x), (x, 3 < x)) + p2 = Piecewise((x, x < 1), (Integral(2 * x), -1 <= x), (x, 3 < x)) + assert p2.doit() == p1 + assert p2.doit(deep=False) == p2 + # issue 17165 + p1 = Sum(y**x, (x, -1, oo)).doit() + assert p1.doit() == p1 + + +def test_piecewise_interval(): + p1 = Piecewise((x, Interval(0, 1).contains(x)), (0, True)) + assert p1.subs(x, -0.5) == 0 + assert p1.subs(x, 0.5) == 0.5 + assert p1.diff(x) == Piecewise((1, Interval(0, 1).contains(x)), (0, True)) + assert integrate(p1, x) == Piecewise( + (0, x <= 0), + (x**2/2, x <= 1), + (S.Half, True)) + + +def test_piecewise_exclusive(): + p = Piecewise((0, x < 0), (S.Half, x <= 0), (1, True)) + assert piecewise_exclusive(p) == Piecewise((0, x < 0), (S.Half, Eq(x, 0)), + (1, x > 0), evaluate=False) + assert piecewise_exclusive(p + 2) == Piecewise((0, x < 0), (S.Half, Eq(x, 0)), + (1, x > 0), evaluate=False) + 2 + assert piecewise_exclusive(Piecewise((1, y <= 0), + (-Piecewise((2, y >= 0)), True))) == \ + Piecewise((1, y <= 0), + (-Piecewise((2, y >= 0), + (S.NaN, y < 0), evaluate=False), y > 0), evaluate=False) + assert piecewise_exclusive(Piecewise((1, x > y))) == Piecewise((1, x > y), + (S.NaN, x <= y), + evaluate=False) + assert piecewise_exclusive(Piecewise((1, x > y)), + skip_nan=True) == Piecewise((1, x > y)) + + xr, yr = symbols('xr, yr', real=True) + + p1 = Piecewise((1, xr < 0), (2, True), evaluate=False) + p1x = Piecewise((1, xr < 0), (2, xr >= 0), evaluate=False) + + p2 = Piecewise((p1, yr < 0), (3, True), evaluate=False) + p2x = Piecewise((p1, yr < 0), (3, yr >= 0), evaluate=False) + p2xx = Piecewise((p1x, yr < 0), (3, yr >= 0), evaluate=False) + + assert piecewise_exclusive(p2) == p2xx + assert piecewise_exclusive(p2, deep=False) == p2x + + +def test_piecewise_collapse(): + assert Piecewise((x, True)) == x + a = x < 1 + assert Piecewise((x, a), (x + 1, a)) == Piecewise((x, a)) + assert Piecewise((x, a), (x + 1, a.reversed)) == Piecewise((x, a)) + b = x < 5 + def canonical(i): + if isinstance(i, Piecewise): + return Piecewise(*i.args) + return i + for args in [ + ((1, a), (Piecewise((2, a), (3, b)), b)), + ((1, a), (Piecewise((2, a), (3, b.reversed)), b)), + ((1, a), (Piecewise((2, a), (3, b)), b), (4, True)), + ((1, a), (Piecewise((2, a), (3, b), (4, True)), b)), + ((1, a), (Piecewise((2, a), (3, b), (4, True)), b), (5, True))]: + for i in (0, 2, 10): + assert canonical( + Piecewise(*args, evaluate=False).subs(x, i) + ) == canonical(Piecewise(*args).subs(x, i)) + r1, r2, r3, r4 = symbols('r1:5') + a = x < r1 + b = x < r2 + c = x < r3 + d = x < r4 + assert Piecewise((1, a), (Piecewise( + (2, a), (3, b), (4, c)), b), (5, c) + ) == Piecewise((1, a), (3, b), (5, c)) + assert Piecewise((1, a), (Piecewise( + (2, a), (3, b), (4, c), (6, True)), c), (5, d) + ) == Piecewise((1, a), (Piecewise( + (3, b), (4, c)), c), (5, d)) + assert Piecewise((1, Or(a, d)), (Piecewise( + (2, d), (3, b), (4, c)), b), (5, c) + ) == Piecewise((1, Or(a, d)), (Piecewise( + (2, d), (3, b)), b), (5, c)) + assert Piecewise((1, c), (2, ~c), (3, S.true) + ) == Piecewise((1, c), (2, S.true)) + assert Piecewise((1, c), (2, And(~c, b)), (3,True) + ) == Piecewise((1, c), (2, b), (3, True)) + assert Piecewise((1, c), (2, Or(~c, b)), (3,True) + ).subs(dict(zip((r1, r2, r3, r4, x), (1, 2, 3, 4, 3.5)))) == 2 + assert Piecewise((1, c), (2, ~c)) == Piecewise((1, c), (2, True)) + + +def test_piecewise_lambdify(): + p = Piecewise( + (x**2, x < 0), + (x, Interval(0, 1, False, True).contains(x)), + (2 - x, x >= 1), + (0, True) + ) + + f = lambdify(x, p) + assert f(-2.0) == 4.0 + assert f(0.0) == 0.0 + assert f(0.5) == 0.5 + assert f(2.0) == 0.0 + + +def test_piecewise_series(): + from sympy.series.order import O + p1 = Piecewise((sin(x), x < 0), (cos(x), x > 0)) + p2 = Piecewise((x + O(x**2), x < 0), (1 + O(x**2), x > 0)) + assert p1.nseries(x, n=2) == p2 + + +def test_piecewise_as_leading_term(): + p1 = Piecewise((1/x, x > 1), (0, True)) + p2 = Piecewise((x, x > 1), (0, True)) + p3 = Piecewise((1/x, x > 1), (x, True)) + p4 = Piecewise((x, x > 1), (1/x, True)) + p5 = Piecewise((1/x, x > 1), (x, True)) + p6 = Piecewise((1/x, x < 1), (x, True)) + p7 = Piecewise((x, x < 1), (1/x, True)) + p8 = Piecewise((x, x > 1), (1/x, True)) + assert p1.as_leading_term(x) == 0 + assert p2.as_leading_term(x) == 0 + assert p3.as_leading_term(x) == x + assert p4.as_leading_term(x) == 1/x + assert p5.as_leading_term(x) == x + assert p6.as_leading_term(x) == 1/x + assert p7.as_leading_term(x) == x + assert p8.as_leading_term(x) == 1/x + + +def test_piecewise_complex(): + p1 = Piecewise((2, x < 0), (1, 0 <= x)) + p2 = Piecewise((2*I, x < 0), (I, 0 <= x)) + p3 = Piecewise((I*x, x > 1), (1 + I, True)) + p4 = Piecewise((-I*conjugate(x), x > 1), (1 - I, True)) + + assert conjugate(p1) == p1 + assert conjugate(p2) == piecewise_fold(-p2) + assert conjugate(p3) == p4 + + assert p1.is_imaginary is False + assert p1.is_real is True + assert p2.is_imaginary is True + assert p2.is_real is False + assert p3.is_imaginary is None + assert p3.is_real is None + + assert p1.as_real_imag() == (p1, 0) + assert p2.as_real_imag() == (0, -I*p2) + + +def test_conjugate_transpose(): + A, B = symbols("A B", commutative=False) + p = Piecewise((A*B**2, x > 0), (A**2*B, True)) + assert p.adjoint() == \ + Piecewise((adjoint(A*B**2), x > 0), (adjoint(A**2*B), True)) + assert p.conjugate() == \ + Piecewise((conjugate(A*B**2), x > 0), (conjugate(A**2*B), True)) + assert p.transpose() == \ + Piecewise((transpose(A*B**2), x > 0), (transpose(A**2*B), True)) + + +def test_piecewise_evaluate(): + assert Piecewise((x, True)) == x + assert Piecewise((x, True), evaluate=True) == x + assert Piecewise((1, Eq(1, x))).args == ((1, Eq(x, 1)),) + assert Piecewise((1, Eq(1, x)), evaluate=False).args == ( + (1, Eq(1, x)),) + # like the additive and multiplicative identities that + # cannot be kept in Add/Mul, we also do not keep a single True + p = Piecewise((x, True), evaluate=False) + assert p == x + + +def test_as_expr_set_pairs(): + assert Piecewise((x, x > 0), (-x, x <= 0)).as_expr_set_pairs() == \ + [(x, Interval(0, oo, True, True)), (-x, Interval(-oo, 0))] + + assert Piecewise(((x - 2)**2, x >= 0), (0, True)).as_expr_set_pairs() == \ + [((x - 2)**2, Interval(0, oo)), (0, Interval(-oo, 0, True, True))] + + +def test_S_srepr_is_identity(): + p = Piecewise((10, Eq(x, 0)), (12, True)) + q = S(srepr(p)) + assert p == q + + +def test_issue_12587(): + # sort holes into intervals + p = Piecewise((1, x > 4), (2, Not((x <= 3) & (x > -1))), (3, True)) + assert p.integrate((x, -5, 5)) == 23 + p = Piecewise((1, x > 1), (2, x < y), (3, True)) + lim = x, -3, 3 + ans = p.integrate(lim) + for i in range(-1, 3): + assert ans.subs(y, i) == p.subs(y, i).integrate(lim) + + +def test_issue_11045(): + assert integrate(1/(x*sqrt(x**2 - 1)), (x, 1, 2)) == pi/3 + + # handle And with Or arguments + assert Piecewise((1, And(Or(x < 1, x > 3), x < 2)), (0, True) + ).integrate((x, 0, 3)) == 1 + + # hidden false + assert Piecewise((1, x > 1), (2, x > x + 1), (3, True) + ).integrate((x, 0, 3)) == 5 + # targetcond is Eq + assert Piecewise((1, x > 1), (2, Eq(1, x)), (3, True) + ).integrate((x, 0, 4)) == 6 + # And has Relational needing to be solved + assert Piecewise((1, And(2*x > x + 1, x < 2)), (0, True) + ).integrate((x, 0, 3)) == 1 + # Or has Relational needing to be solved + assert Piecewise((1, Or(2*x > x + 2, x < 1)), (0, True) + ).integrate((x, 0, 3)) == 2 + # ignore hidden false (handled in canonicalization) + assert Piecewise((1, x > 1), (2, x > x + 1), (3, True) + ).integrate((x, 0, 3)) == 5 + # watch for hidden True Piecewise + assert Piecewise((2, Eq(1 - x, x*(1/x - 1))), (0, True) + ).integrate((x, 0, 3)) == 6 + + # overlapping conditions of targetcond are recognized and ignored; + # the condition x > 3 will be pre-empted by the first condition + assert Piecewise((1, Or(x < 1, x > 2)), (2, x > 3), (3, True) + ).integrate((x, 0, 4)) == 6 + + # convert Ne to Or + assert Piecewise((1, Ne(x, 0)), (2, True) + ).integrate((x, -1, 1)) == 2 + + # no default but well defined + assert Piecewise((x, (x > 1) & (x < 3)), (1, (x < 4)) + ).integrate((x, 1, 4)) == 5 + + p = Piecewise((x, (x > 1) & (x < 3)), (1, (x < 4))) + nan = Undefined + i = p.integrate((x, 1, y)) + assert i == Piecewise( + (y - 1, y < 1), + (Min(3, y)**2/2 - Min(3, y) + Min(4, y) - S.Half, + y <= Min(4, y)), + (nan, True)) + assert p.integrate((x, 1, -1)) == i.subs(y, -1) + assert p.integrate((x, 1, 4)) == 5 + assert p.integrate((x, 1, 5)) is nan + + # handle Not + p = Piecewise((1, x > 1), (2, Not(And(x > 1, x< 3))), (3, True)) + assert p.integrate((x, 0, 3)) == 4 + + # handle updating of int_expr when there is overlap + p = Piecewise( + (1, And(5 > x, x > 1)), + (2, Or(x < 3, x > 7)), + (4, x < 8)) + assert p.integrate((x, 0, 10)) == 20 + + # And with Eq arg handling + assert Piecewise((1, x < 1), (2, And(Eq(x, 3), x > 1)) + ).integrate((x, 0, 3)) is S.NaN + assert Piecewise((1, x < 1), (2, And(Eq(x, 3), x > 1)), (3, True) + ).integrate((x, 0, 3)) == 7 + assert Piecewise((1, x < 0), (2, And(Eq(x, 3), x < 1)), (3, True) + ).integrate((x, -1, 1)) == 4 + # middle condition doesn't matter: it's a zero width interval + assert Piecewise((1, x < 1), (2, Eq(x, 3) & (y < x)), (3, True) + ).integrate((x, 0, 3)) == 7 + + +def test_holes(): + nan = Undefined + assert Piecewise((1, x < 2)).integrate(x) == Piecewise( + (x, x < 2), (nan, True)) + assert Piecewise((1, And(x > 1, x < 2))).integrate(x) == Piecewise( + (nan, x < 1), (x, x < 2), (nan, True)) + assert Piecewise((1, And(x > 1, x < 2))).integrate((x, 0, 3)) is nan + assert Piecewise((1, And(x > 0, x < 4))).integrate((x, 1, 3)) == 2 + + # this also tests that the integrate method is used on non-Piecwise + # arguments in _eval_integral + A, B = symbols("A B") + a, b = symbols('a b', real=True) + assert Piecewise((A, And(x < 0, a < 1)), (B, Or(x < 1, a > 2)) + ).integrate(x) == Piecewise( + (B*x, (a > 2)), + (Piecewise((A*x, x < 0), (B*x, x < 1), (nan, True)), a < 1), + (Piecewise((B*x, x < 1), (nan, True)), True)) + + +def test_issue_11922(): + def f(x): + return Piecewise((0, x < -1), (1 - x**2, x < 1), (0, True)) + autocorr = lambda k: ( + f(x) * f(x + k)).integrate((x, -1, 1)) + assert autocorr(1.9) > 0 + k = symbols('k') + good_autocorr = lambda k: ( + (1 - x**2) * f(x + k)).integrate((x, -1, 1)) + a = good_autocorr(k) + assert a.subs(k, 3) == 0 + k = symbols('k', positive=True) + a = good_autocorr(k) + assert a.subs(k, 3) == 0 + assert Piecewise((0, x < 1), (10, (x >= 1)) + ).integrate() == Piecewise((0, x < 1), (10*x - 10, True)) + + +def test_issue_5227(): + f = 0.0032513612725229*Piecewise((0, x < -80.8461538461539), + (-0.0160799238820171*x + 1.33215984776403, x < 2), + (Piecewise((0.3, x > 123), (0.7, True)) + + Piecewise((0.4, x > 2), (0.6, True)), x <= + 123), (-0.00817409766454352*x + 2.10541401273885, x < + 380.571428571429), (0, True)) + i = integrate(f, (x, -oo, oo)) + assert i == Integral(f, (x, -oo, oo)).doit() + assert str(i) == '1.00195081676351' + assert Piecewise((1, x - y < 0), (0, True) + ).integrate(y) == Piecewise((0, y <= x), (-x + y, True)) + + +def test_issue_10137(): + a = Symbol('a', real=True) + b = Symbol('b', real=True) + x = Symbol('x', real=True) + y = Symbol('y', real=True) + p0 = Piecewise((0, Or(x < a, x > b)), (1, True)) + p1 = Piecewise((0, Or(a > x, b < x)), (1, True)) + assert integrate(p0, (x, y, oo)) == integrate(p1, (x, y, oo)) + p3 = Piecewise((1, And(0 < x, x < a)), (0, True)) + p4 = Piecewise((1, And(a > x, x > 0)), (0, True)) + ip3 = integrate(p3, x) + assert ip3 == Piecewise( + (0, x <= 0), + (x, x <= Max(0, a)), + (Max(0, a), True)) + ip4 = integrate(p4, x) + assert ip4 == ip3 + assert p3.integrate((x, 2, 4)) == Min(4, Max(2, a)) - 2 + assert p4.integrate((x, 2, 4)) == Min(4, Max(2, a)) - 2 + + +def test_stackoverflow_43852159(): + f = lambda x: Piecewise((1, (x >= -1) & (x <= 1)), (0, True)) + Conv = lambda x: integrate(f(x - y)*f(y), (y, -oo, +oo)) + cx = Conv(x) + assert cx.subs(x, -1.5) == cx.subs(x, 1.5) + assert cx.subs(x, 3) == 0 + assert piecewise_fold(f(x - y)*f(y)) == Piecewise( + (1, (y >= -1) & (y <= 1) & (x - y >= -1) & (x - y <= 1)), + (0, True)) + + +def test_issue_12557(): + ''' + # 3200 seconds to compute the fourier part of issue + import sympy as sym + x,y,z,t = sym.symbols('x y z t') + k = sym.symbols("k", integer=True) + fourier = sym.fourier_series(sym.cos(k*x)*sym.sqrt(x**2), + (x, -sym.pi, sym.pi)) + assert fourier == FourierSeries( + sqrt(x**2)*cos(k*x), (x, -pi, pi), (Piecewise((pi**2, + Eq(k, 0)), (2*(-1)**k/k**2 - 2/k**2, True))/(2*pi), + SeqFormula(Piecewise((pi**2, (Eq(_n, 0) & Eq(k, 0)) | (Eq(_n, 0) & + Eq(_n, k) & Eq(k, 0)) | (Eq(_n, 0) & Eq(k, 0) & Eq(_n, -k)) | (Eq(_n, + 0) & Eq(_n, k) & Eq(k, 0) & Eq(_n, -k))), (pi**2/2, Eq(_n, k) | Eq(_n, + -k) | (Eq(_n, 0) & Eq(_n, k)) | (Eq(_n, k) & Eq(k, 0)) | (Eq(_n, 0) & + Eq(_n, -k)) | (Eq(_n, k) & Eq(_n, -k)) | (Eq(k, 0) & Eq(_n, -k)) | + (Eq(_n, 0) & Eq(_n, k) & Eq(_n, -k)) | (Eq(_n, k) & Eq(k, 0) & Eq(_n, + -k))), ((-1)**k*pi**2*_n**3*sin(pi*_n)/(pi*_n**4 - 2*pi*_n**2*k**2 + + pi*k**4) - (-1)**k*pi**2*_n**3*sin(pi*_n)/(-pi*_n**4 + 2*pi*_n**2*k**2 + - pi*k**4) + (-1)**k*pi*_n**2*cos(pi*_n)/(pi*_n**4 - 2*pi*_n**2*k**2 + + pi*k**4) - (-1)**k*pi*_n**2*cos(pi*_n)/(-pi*_n**4 + 2*pi*_n**2*k**2 - + pi*k**4) - (-1)**k*pi**2*_n*k**2*sin(pi*_n)/(pi*_n**4 - + 2*pi*_n**2*k**2 + pi*k**4) + + (-1)**k*pi**2*_n*k**2*sin(pi*_n)/(-pi*_n**4 + 2*pi*_n**2*k**2 - + pi*k**4) + (-1)**k*pi*k**2*cos(pi*_n)/(pi*_n**4 - 2*pi*_n**2*k**2 + + pi*k**4) - (-1)**k*pi*k**2*cos(pi*_n)/(-pi*_n**4 + 2*pi*_n**2*k**2 - + pi*k**4) - (2*_n**2 + 2*k**2)/(_n**4 - 2*_n**2*k**2 + k**4), + True))*cos(_n*x)/pi, (_n, 1, oo)), SeqFormula(0, (_k, 1, oo)))) + ''' + x = symbols("x", real=True) + k = symbols('k', integer=True, finite=True) + abs2 = lambda x: Piecewise((-x, x <= 0), (x, x > 0)) + assert integrate(abs2(x), (x, -pi, pi)) == pi**2 + func = cos(k*x)*sqrt(x**2) + assert integrate(func, (x, -pi, pi)) == Piecewise( + (2*(-1)**k/k**2 - 2/k**2, Ne(k, 0)), (pi**2, True)) + +def test_issue_6900(): + from itertools import permutations + t0, t1, T, t = symbols('t0, t1 T t') + f = Piecewise((0, t < t0), (x, And(t0 <= t, t < t1)), (0, t >= t1)) + g = f.integrate(t) + assert g == Piecewise( + (0, t <= t0), + (t*x - t0*x, t <= Max(t0, t1)), + (-t0*x + x*Max(t0, t1), True)) + for i in permutations(range(2)): + reps = dict(zip((t0,t1), i)) + for tt in range(-1,3): + assert (g.xreplace(reps).subs(t,tt) == + f.xreplace(reps).integrate(t).subs(t,tt)) + lim = Tuple(t, t0, T) + g = f.integrate(lim) + ans = Piecewise( + (-t0*x + x*Min(T, Max(t0, t1)), T > t0), + (0, True)) + for i in permutations(range(3)): + reps = dict(zip((t0,t1,T), i)) + tru = f.xreplace(reps).integrate(lim.xreplace(reps)) + assert tru == ans.xreplace(reps) + assert g == ans + + +def test_issue_10122(): + assert solve(abs(x) + abs(x - 1) - 1 > 0, x + ) == Or(And(-oo < x, x < S.Zero), And(S.One < x, x < oo)) + + +def test_issue_4313(): + u = Piecewise((0, x <= 0), (1, x >= a), (x/a, True)) + e = (u - u.subs(x, y))**2/(x - y)**2 + M = Max(0, a) + assert integrate(e, x).expand() == Piecewise( + (Piecewise( + (0, x <= 0), + (-y**2/(a**2*x - a**2*y) + x/a**2 - 2*y*log(-y)/a**2 + + 2*y*log(x - y)/a**2 - y/a**2, x <= M), + (-y**2/(-a**2*y + a**2*M) + 1/(-y + M) - + 1/(x - y) - 2*y*log(-y)/a**2 + 2*y*log(-y + + M)/a**2 - y/a**2 + M/a**2, True)), + ((a <= y) & (y <= 0)) | ((y <= 0) & (y > -oo))), + (Piecewise( + (-1/(x - y), x <= 0), + (-a**2/(a**2*x - a**2*y) + 2*a*y/(a**2*x - a**2*y) - + y**2/(a**2*x - a**2*y) + 2*log(-y)/a - 2*log(x - y)/a + + 2/a + x/a**2 - 2*y*log(-y)/a**2 + 2*y*log(x - y)/a**2 - + y/a**2, x <= M), + (-a**2/(-a**2*y + a**2*M) + 2*a*y/(-a**2*y + + a**2*M) - y**2/(-a**2*y + a**2*M) + + 2*log(-y)/a - 2*log(-y + M)/a + 2/a - + 2*y*log(-y)/a**2 + 2*y*log(-y + M)/a**2 - + y/a**2 + M/a**2, True)), + a <= y), + (Piecewise( + (-y**2/(a**2*x - a**2*y), x <= 0), + (x/a**2 + y/a**2, x <= M), + (a**2/(-a**2*y + a**2*M) - + a**2/(a**2*x - a**2*y) - 2*a*y/(-a**2*y + a**2*M) + + 2*a*y/(a**2*x - a**2*y) + y**2/(-a**2*y + a**2*M) - + y**2/(a**2*x - a**2*y) + y/a**2 + M/a**2, True)), + True)) + + +def test__intervals(): + assert Piecewise((x + 2, Eq(x, 3)))._intervals(x) == (True, []) + assert Piecewise( + (1, x > x + 1), + (Piecewise((1, x < x + 1)), 2*x < 2*x + 1), + (1, True))._intervals(x) == (True, [(-oo, oo, 1, 1)]) + assert Piecewise((1, Ne(x, I)), (0, True))._intervals(x) == (True, + [(-oo, oo, 1, 0)]) + assert Piecewise((-cos(x), sin(x) >= 0), (cos(x), True) + )._intervals(x) == (True, + [(0, pi, -cos(x), 0), (-oo, oo, cos(x), 1)]) + # the following tests that duplicates are removed and that non-Eq + # generated zero-width intervals are removed + assert Piecewise((1, Abs(x**(-2)) > 1), (0, True) + )._intervals(x) == (True, + [(-1, 0, 1, 0), (0, 1, 1, 0), (-oo, oo, 0, 1)]) + + +def test_containment(): + a, b, c, d, e = [1, 2, 3, 4, 5] + p = (Piecewise((d, x > 1), (e, True))* + Piecewise((a, Abs(x - 1) < 1), (b, Abs(x - 2) < 2), (c, True))) + assert p.integrate(x).diff(x) == Piecewise( + (c*e, x <= 0), + (a*e, x <= 1), + (a*d, x < 2), # this is what we want to get right + (b*d, x < 4), + (c*d, True)) + + +def test_piecewise_with_DiracDelta(): + d1 = DiracDelta(x - 1) + assert integrate(d1, (x, -oo, oo)) == 1 + assert integrate(d1, (x, 0, 2)) == 1 + assert Piecewise((d1, Eq(x, 2)), (0, True)).integrate(x) == 0 + assert Piecewise((d1, x < 2), (0, True)).integrate(x) == Piecewise( + (Heaviside(x - 1), x < 2), (1, True)) + # TODO raise error if function is discontinuous at limit of + # integration, e.g. integrate(d1, (x, -2, 1)) or Piecewise( + # (d1, Eq(x, 1) + + +def test_issue_10258(): + assert Piecewise((0, x < 1), (1, True)).is_zero is None + assert Piecewise((-1, x < 1), (1, True)).is_zero is False + a = Symbol('a', zero=True) + assert Piecewise((0, x < 1), (a, True)).is_zero + assert Piecewise((1, x < 1), (a, x < 3)).is_zero is None + a = Symbol('a') + assert Piecewise((0, x < 1), (a, True)).is_zero is None + assert Piecewise((0, x < 1), (1, True)).is_nonzero is None + assert Piecewise((1, x < 1), (2, True)).is_nonzero + assert Piecewise((0, x < 1), (oo, True)).is_finite is None + assert Piecewise((0, x < 1), (1, True)).is_finite + b = Basic() + assert Piecewise((b, x < 1)).is_finite is None + + # 10258 + c = Piecewise((1, x < 0), (2, True)) < 3 + assert c != True + assert piecewise_fold(c) == True + + +def test_issue_10087(): + a, b = Piecewise((x, x > 1), (2, True)), Piecewise((x, x > 3), (3, True)) + m = a*b + f = piecewise_fold(m) + for i in (0, 2, 4): + assert m.subs(x, i) == f.subs(x, i) + m = a + b + f = piecewise_fold(m) + for i in (0, 2, 4): + assert m.subs(x, i) == f.subs(x, i) + + +def test_issue_8919(): + c = symbols('c:5') + x = symbols("x") + f1 = Piecewise((c[1], x < 1), (c[2], True)) + f2 = Piecewise((c[3], x < Rational(1, 3)), (c[4], True)) + assert integrate(f1*f2, (x, 0, 2) + ) == c[1]*c[3]/3 + 2*c[1]*c[4]/3 + c[2]*c[4] + f1 = Piecewise((0, x < 1), (2, True)) + f2 = Piecewise((3, x < 2), (0, True)) + assert integrate(f1*f2, (x, 0, 3)) == 6 + + y = symbols("y", positive=True) + a, b, c, x, z = symbols("a,b,c,x,z", real=True) + I = Integral(Piecewise( + (0, (x >= y) | (x < 0) | (b > c)), + (a, True)), (x, 0, z)) + ans = I.doit() + assert ans == Piecewise((0, b > c), (a*Min(y, z) - a*Min(0, z), True)) + for cond in (True, False): + for yy in range(1, 3): + for zz in range(-yy, 0, yy): + reps = [(b > c, cond), (y, yy), (z, zz)] + assert ans.subs(reps) == I.subs(reps).doit() + + +def test_unevaluated_integrals(): + f = Function('f') + p = Piecewise((1, Eq(f(x) - 1, 0)), (2, x - 10 < 0), (0, True)) + assert p.integrate(x) == Integral(p, x) + assert p.integrate((x, 0, 5)) == Integral(p, (x, 0, 5)) + # test it by replacing f(x) with x%2 which will not + # affect the answer: the integrand is essentially 2 over + # the domain of integration + assert Integral(p, (x, 0, 5)).subs(f(x), x%2).n() == 10.0 + + # this is a test of using _solve_inequality when + # solve_univariate_inequality fails + assert p.integrate(y) == Piecewise( + (y, Eq(f(x), 1) | ((x < 10) & Eq(f(x), 1))), + (2*y, (x > -oo) & (x < 10)), (0, True)) + + +def test_conditions_as_alternate_booleans(): + a, b, c = symbols('a:c') + assert Piecewise((x, Piecewise((y < 1, x > 0), (y > 1, True))) + ) == Piecewise((x, ITE(x > 0, y < 1, y > 1))) + + +def test_Piecewise_rewrite_as_ITE(): + a, b, c, d = symbols('a:d') + + def _ITE(*args): + return Piecewise(*args).rewrite(ITE) + + assert _ITE((a, x < 1), (b, x >= 1)) == ITE(x < 1, a, b) + assert _ITE((a, x < 1), (b, x < oo)) == ITE(x < 1, a, b) + assert _ITE((a, x < 1), (b, Or(y < 1, x < oo)), (c, y > 0) + ) == ITE(x < 1, a, b) + assert _ITE((a, x < 1), (b, True)) == ITE(x < 1, a, b) + assert _ITE((a, x < 1), (b, x < 2), (c, True) + ) == ITE(x < 1, a, ITE(x < 2, b, c)) + assert _ITE((a, x < 1), (b, y < 2), (c, True) + ) == ITE(x < 1, a, ITE(y < 2, b, c)) + assert _ITE((a, x < 1), (b, x < oo), (c, y < 1) + ) == ITE(x < 1, a, b) + assert _ITE((a, x < 1), (c, y < 1), (b, x < oo), (d, True) + ) == ITE(x < 1, a, ITE(y < 1, c, b)) + assert _ITE((a, x < 0), (b, Or(x < oo, y < 1)) + ) == ITE(x < 0, a, b) + raises(TypeError, lambda: _ITE((x + 1, x < 1), (x, True))) + # if `a` in the following were replaced with y then the coverage + # is complete but something other than as_set would need to be + # used to detect this + raises(NotImplementedError, lambda: _ITE((x, x < y), (y, x >= a))) + raises(ValueError, lambda: _ITE((a, x < 2), (b, x > 3))) + + +def test_Piecewise_replace_relational_27538(): + x, y = symbols('x, y') + p1 = Piecewise( + (0, Eq(x, True)), + (1, True), + ) + p2 = p1.xreplace({x: y < 1}) + assert p2.subs(y, 0) == 0 + assert p2.subs(y, 1) == 1 + + +def test_issue_14052(): + assert integrate(abs(sin(x)), (x, 0, 2*pi)) == 4 + + +def test_issue_14240(): + assert piecewise_fold( + Piecewise((1, a), (2, b), (4, True)) + + Piecewise((8, a), (16, True)) + ) == Piecewise((9, a), (18, b), (20, True)) + assert piecewise_fold( + Piecewise((2, a), (3, b), (5, True)) * + Piecewise((7, a), (11, True)) + ) == Piecewise((14, a), (33, b), (55, True)) + # these will hang if naive folding is used + assert piecewise_fold(Add(*[ + Piecewise((i, a), (0, True)) for i in range(40)]) + ) == Piecewise((780, a), (0, True)) + assert piecewise_fold(Mul(*[ + Piecewise((i, a), (0, True)) for i in range(1, 41)]) + ) == Piecewise((factorial(40), a), (0, True)) + + +def test_issue_14787(): + x = Symbol('x') + f = Piecewise((x, x < 1), ((S(58) / 7), True)) + assert str(f.evalf()) == "Piecewise((x, x < 1), (8.28571428571429, True))" + +def test_issue_21481(): + b, e = symbols('b e') + C = Piecewise( + (2, + ((b > 1) & (e > 0)) | + ((b > 0) & (b < 1) & (e < 0)) | + ((e >= 2) & (b < -1) & Eq(Mod(e, 2), 0)) | + ((e <= -2) & (b > -1) & (b < 0) & Eq(Mod(e, 2), 0))), + (S.Half, + ((b > 1) & (e < 0)) | + ((b > 0) & (e > 0) & (b < 1)) | + ((e <= -2) & (b < -1) & Eq(Mod(e, 2), 0)) | + ((e >= 2) & (b > -1) & (b < 0) & Eq(Mod(e, 2), 0))), + (-S.Half, + Eq(Mod(e, 2), 1) & + (((e <= -1) & (b < -1)) | ((e >= 1) & (b > -1) & (b < 0)))), + (-2, + ((e >= 1) & (b < -1) & Eq(Mod(e, 2), 1)) | + ((e <= -1) & (b > -1) & (b < 0) & Eq(Mod(e, 2), 1))) + ) + A = Piecewise( + (1, Eq(b, 1) | Eq(e, 0) | (Eq(b, -1) & Eq(Mod(e, 2), 0))), + (0, Eq(b, 0) & (e > 0)), + (-1, Eq(b, -1) & Eq(Mod(e, 2), 1)), + (C, Eq(im(b), 0) & Eq(im(e), 0)) + ) + + B = piecewise_fold(A) + sa = A.simplify() + sb = B.simplify() + v = (-2, -1, -S.Half, 0, S.Half, 1, 2) + for i in v: + for j in v: + r = {b:i, e:j} + ok = [k.xreplace(r) for k in (A, B, sa, sb)] + assert len(set(ok)) == 1 + + +def test_issue_8458(): + x, y = symbols('x y') + # Original issue + p1 = Piecewise((0, Eq(x, 0)), (sin(x), True)) + assert p1.simplify() == sin(x) + # Slightly larger variant + p2 = Piecewise((x, Eq(x, 0)), (4*x + (y-2)**4, Eq(x, 0) & Eq(x+y, 2)), (sin(x), True)) + assert p2.simplify() == sin(x) + # Test for problem highlighted during review + p3 = Piecewise((x+1, Eq(x, -1)), (4*x + (y-2)**4, Eq(x, 0) & Eq(x+y, 2)), (sin(x), True)) + assert p3.simplify() == Piecewise((0, Eq(x, -1)), (sin(x), True)) + + +def test_issue_16417(): + z = Symbol('z') + assert unchanged(Piecewise, (1, Or(Eq(im(z), 0), Gt(re(z), 0))), (2, True)) + + x = Symbol('x') + assert unchanged(Piecewise, (S.Pi, re(x) < 0), + (0, Or(re(x) > 0, Ne(im(x), 0))), + (S.NaN, True)) + r = Symbol('r', real=True) + p = Piecewise((S.Pi, re(r) < 0), + (0, Or(re(r) > 0, Ne(im(r), 0))), + (S.NaN, True)) + assert p == Piecewise((S.Pi, r < 0), + (0, r > 0), + (S.NaN, True), evaluate=False) + # Does not work since imaginary != 0... + #i = Symbol('i', imaginary=True) + #p = Piecewise((S.Pi, re(i) < 0), + # (0, Or(re(i) > 0, Ne(im(i), 0))), + # (S.NaN, True)) + #assert p == Piecewise((0, Ne(im(i), 0)), + # (S.NaN, True), evaluate=False) + i = I*r + p = Piecewise((S.Pi, re(i) < 0), + (0, Or(re(i) > 0, Ne(im(i), 0))), + (S.NaN, True)) + assert p == Piecewise((0, Ne(im(i), 0)), + (S.NaN, True), evaluate=False) + assert p == Piecewise((0, Ne(r, 0)), + (S.NaN, True), evaluate=False) + + +def test_eval_rewrite_as_KroneckerDelta(): + x, y, z, n, t, m = symbols('x y z n t m') + K = KroneckerDelta + f = lambda p: expand(p.rewrite(K)) + + p1 = Piecewise((0, Eq(x, y)), (1, True)) + assert f(p1) == 1 - K(x, y) + + p2 = Piecewise((x, Eq(y,0)), (z, Eq(t,0)), (n, True)) + assert f(p2) == n*K(0, t)*K(0, y) - n*K(0, t) - n*K(0, y) + n + \ + x*K(0, y) - z*K(0, t)*K(0, y) + z*K(0, t) + + p3 = Piecewise((1, Ne(x, y)), (0, True)) + assert f(p3) == 1 - K(x, y) + + p4 = Piecewise((1, Eq(x, 3)), (4, True), (5, True)) + assert f(p4) == 4 - 3*K(3, x) + + p5 = Piecewise((3, Ne(x, 2)), (4, Eq(y, 2)), (5, True)) + assert f(p5) == -K(2, x)*K(2, y) + 2*K(2, x) + 3 + + p6 = Piecewise((0, Ne(x, 1) & Ne(y, 4)), (1, True)) + assert f(p6) == -K(1, x)*K(4, y) + K(1, x) + K(4, y) + + p7 = Piecewise((2, Eq(y, 3) & Ne(x, 2)), (1, True)) + assert f(p7) == -K(2, x)*K(3, y) + K(3, y) + 1 + + p8 = Piecewise((4, Eq(x, 3) & Ne(y, 2)), (1, True)) + assert f(p8) == -3*K(2, y)*K(3, x) + 3*K(3, x) + 1 + + p9 = Piecewise((6, Eq(x, 4) & Eq(y, 1)), (1, True)) + assert f(p9) == 5 * K(1, y) * K(4, x) + 1 + + p10 = Piecewise((4, Ne(x, -4) | Ne(y, 1)), (1, True)) + assert f(p10) == -3 * K(-4, x) * K(1, y) + 4 + + p11 = Piecewise((1, Eq(y, 2) | Ne(x, -3)), (2, True)) + assert f(p11) == -K(-3, x)*K(2, y) + K(-3, x) + 1 + + p12 = Piecewise((-1, Eq(x, 1) | Ne(y, 3)), (1, True)) + assert f(p12) == -2*K(1, x)*K(3, y) + 2*K(3, y) - 1 + + p13 = Piecewise((3, Eq(x, 2) | Eq(y, 4)), (1, True)) + assert f(p13) == -2*K(2, x)*K(4, y) + 2*K(2, x) + 2*K(4, y) + 1 + + p14 = Piecewise((1, Ne(x, 0) | Ne(y, 1)), (3, True)) + assert f(p14) == 2 * K(0, x) * K(1, y) + 1 + + p15 = Piecewise((2, Eq(x, 3) | Ne(y, 2)), (3, Eq(x, 4) & Eq(y, 5)), (1, True)) + assert f(p15) == -2*K(2, y)*K(3, x)*K(4, x)*K(5, y) + K(2, y)*K(3, x) + \ + 2*K(2, y)*K(4, x)*K(5, y) - K(2, y) + 2 + + p16 = Piecewise((0, Ne(m, n)), (1, True))*Piecewise((0, Ne(n, t)), (1, True))\ + *Piecewise((0, Ne(n, x)), (1, True)) - Piecewise((0, Ne(t, x)), (1, True)) + assert f(p16) == K(m, n)*K(n, t)*K(n, x) - K(t, x) + + p17 = Piecewise((0, Ne(t, x) & (Ne(m, n) | Ne(n, t) | Ne(n, x))), + (1, Ne(t, x)), (-1, Ne(m, n) | Ne(n, t) | Ne(n, x)), (0, True)) + assert f(p17) == K(m, n)*K(n, t)*K(n, x) - K(t, x) + + p18 = Piecewise((-4, Eq(y, 1) | (Eq(x, -5) & Eq(x, z))), (4, True)) + assert f(p18) == 8*K(-5, x)*K(1, y)*K(x, z) - 8*K(-5, x)*K(x, z) - 8*K(1, y) + 4 + + p19 = Piecewise((0, x > 2), (1, True)) + assert f(p19) == p19 + + p20 = Piecewise((0, And(x < 2, x > -5)), (1, True)) + assert f(p20) == p20 + + p21 = Piecewise((0, Or(x > 1, x < 0)), (1, True)) + assert f(p21) == p21 + + p22 = Piecewise((0, ~((Eq(y, -1) | Ne(x, 0)) & (Ne(x, 1) | Ne(y, -1)))), (1, True)) + assert f(p22) == K(-1, y)*K(0, x) - K(-1, y)*K(1, x) - K(0, x) + 1 + + +@slow +def test_identical_conds_issue(): + from sympy.stats import Uniform, density + u1 = Uniform('u1', 0, 1) + u2 = Uniform('u2', 0, 1) + # Result is quite big, so not really important here (and should ideally be + # simpler). Should not give an exception though. + density(u1 + u2) + + +def test_issue_7370(): + f = Piecewise((1, x <= 2400)) + v = integrate(f, (x, 0, Float("252.4", 30))) + assert str(v) == '252.400000000000000000000000000' + + +def test_issue_14933(): + x = Symbol('x') + y = Symbol('y') + + inp = MatrixSymbol('inp', 1, 1) + rep_dict = {y: inp[0, 0], x: inp[0, 0]} + + p = Piecewise((1, ITE(y > 0, x < 0, True))) + assert p.xreplace(rep_dict) == Piecewise((1, ITE(inp[0, 0] > 0, inp[0, 0] < 0, True))) + + +def test_issue_16715(): + raises(NotImplementedError, lambda: Piecewise((x, x<0), (0, y>1)).as_expr_set_pairs()) + + +def test_issue_20360(): + t, tau = symbols("t tau", real=True) + n = symbols("n", integer=True) + lam = pi * (n - S.Half) + eq = integrate(exp(lam * tau), (tau, 0, t)) + assert eq.simplify() == (2*exp(pi*t*(2*n - 1)/2) - 2)/(pi*(2*n - 1)) + + +def test_piecewise_eval(): + # XXX these tests might need modification if this + # simplification is moved out of eval and into + # boolalg or Piecewise simplification functions + f = lambda x: x.args[0].cond + # unsimplified + assert f(Piecewise((x, (x > -oo) & (x < 3))) + ) == ((x > -oo) & (x < 3)) + assert f(Piecewise((x, (x > -oo) & (x < oo))) + ) == ((x > -oo) & (x < oo)) + assert f(Piecewise((x, (x > -3) & (x < 3))) + ) == ((x > -3) & (x < 3)) + assert f(Piecewise((x, (x > -3) & (x < oo))) + ) == ((x > -3) & (x < oo)) + assert f(Piecewise((x, (x <= 3) & (x > -oo))) + ) == ((x <= 3) & (x > -oo)) + assert f(Piecewise((x, (x <= 3) & (x > -3))) + ) == ((x <= 3) & (x > -3)) + assert f(Piecewise((x, (x >= -3) & (x < 3))) + ) == ((x >= -3) & (x < 3)) + assert f(Piecewise((x, (x >= -3) & (x < oo))) + ) == ((x >= -3) & (x < oo)) + assert f(Piecewise((x, (x >= -3) & (x <= 3))) + ) == ((x >= -3) & (x <= 3)) + # could simplify by keeping only the first + # arg of result + assert f(Piecewise((x, (x <= oo) & (x > -oo))) + ) == (x > -oo) & (x <= oo) + assert f(Piecewise((x, (x <= oo) & (x > -3))) + ) == (x > -3) & (x <= oo) + assert f(Piecewise((x, (x >= -oo) & (x < 3))) + ) == (x < 3) & (x >= -oo) + assert f(Piecewise((x, (x >= -oo) & (x < oo))) + ) == (x < oo) & (x >= -oo) + assert f(Piecewise((x, (x >= -oo) & (x <= 3))) + ) == (x <= 3) & (x >= -oo) + assert f(Piecewise((x, (x >= -oo) & (x <= oo))) + ) == (x <= oo) & (x >= -oo) # but cannot be True unless x is real + assert f(Piecewise((x, (x >= -3) & (x <= oo))) + ) == (x >= -3) & (x <= oo) + assert f(Piecewise((x, (Abs(arg(a)) <= 1) | (Abs(arg(a)) < 1))) + ) == (Abs(arg(a)) <= 1) | (Abs(arg(a)) < 1) + + +def test_issue_22533(): + x = Symbol('x', real=True) + f = Piecewise((-1 / x, x <= 0), (1 / x, True)) + assert integrate(f, x) == Piecewise((-log(x), x <= 0), (log(x), True)) + + +def test_issue_24072(): + assert Piecewise((1, x > 1), (2, x <= 1), (3, x <= 1) + ) == Piecewise((1, x > 1), (2, True)) + + +def test_piecewise__eval_is_meromorphic(): + """ Issue 24127: Tests eval_is_meromorphic auxiliary method """ + x = symbols('x', real=True) + f = Piecewise((1, x < 0), (sqrt(1 - x), True)) + assert f.is_meromorphic(x, I) is None + assert f.is_meromorphic(x, -1) == True + assert f.is_meromorphic(x, 0) == None + assert f.is_meromorphic(x, 1) == False + assert f.is_meromorphic(x, 2) == True + assert f.is_meromorphic(x, Symbol('a')) == None + assert f.is_meromorphic(x, Symbol('a', real=True)) == None diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_trigonometric.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_trigonometric.py new file mode 100644 index 0000000000000000000000000000000000000000..815f424093aac72ee3a078d8ce62e5c195a625dc --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/tests/test_trigonometric.py @@ -0,0 +1,2236 @@ +from sympy.calculus.accumulationbounds import AccumBounds +from sympy.core.add import Add +from sympy.core.function import (Lambda, diff) +from sympy.core.mod import Mod +from sympy.core.mul import Mul +from sympy.core.numbers import (E, Float, I, Rational, nan, oo, pi, zoo) +from sympy.core.power import Pow +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.complexes import (arg, conjugate, im, re) +from sympy.functions.elementary.exponential import (exp, log) +from sympy.functions.elementary.hyperbolic import (acoth, asinh, atanh, cosh, coth, sinh, tanh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (acos, acot, acsc, asec, asin, atan, atan2, + cos, cot, csc, sec, sin, sinc, tan) +from sympy.functions.special.bessel import (besselj, jn) +from sympy.functions.special.delta_functions import Heaviside +from sympy.matrices.dense import Matrix +from sympy.polys.polytools import (cancel, gcd) +from sympy.series.limits import limit +from sympy.series.order import O +from sympy.series.series import series +from sympy.sets.fancysets import ImageSet +from sympy.sets.sets import (FiniteSet, Interval) +from sympy.simplify.simplify import simplify +from sympy.core.expr import unchanged +from sympy.core.function import ArgumentIndexError, PoleError +from sympy.core.relational import Ne, Eq +from sympy.functions.elementary.piecewise import Piecewise +from sympy.sets.setexpr import SetExpr +from sympy.testing.pytest import XFAIL, slow, raises + + +x, y, z = symbols('x y z') +r = Symbol('r', real=True) +k, m = symbols('k m', integer=True) +p = Symbol('p', positive=True) +n = Symbol('n', negative=True) +np = Symbol('p', nonpositive=True) +nn = Symbol('n', nonnegative=True) +nz = Symbol('nz', nonzero=True) +ep = Symbol('ep', extended_positive=True) +en = Symbol('en', extended_negative=True) +enp = Symbol('ep', extended_nonpositive=True) +enn = Symbol('en', extended_nonnegative=True) +enz = Symbol('enz', extended_nonzero=True) +a = Symbol('a', algebraic=True) +na = Symbol('na', nonzero=True, algebraic=True) + + +def test_sin(): + x, y = symbols('x y') + z = symbols('z', imaginary=True) + + assert sin.nargs == FiniteSet(1) + assert sin(nan) is nan + assert sin(zoo) is nan + + assert sin(oo) == AccumBounds(-1, 1) + assert sin(oo) - sin(oo) == AccumBounds(-2, 2) + assert sin(oo*I) == oo*I + assert sin(-oo*I) == -oo*I + assert 0*sin(oo) is S.Zero + assert 0/sin(oo) is S.Zero + assert 0 + sin(oo) == AccumBounds(-1, 1) + assert 5 + sin(oo) == AccumBounds(4, 6) + + assert sin(0) == 0 + + assert sin(z*I) == I*sinh(z) + assert sin(asin(x)) == x + assert sin(atan(x)) == x / sqrt(1 + x**2) + assert sin(acos(x)) == sqrt(1 - x**2) + assert sin(acot(x)) == 1 / (sqrt(1 + 1 / x**2) * x) + assert sin(acsc(x)) == 1 / x + assert sin(asec(x)) == sqrt(1 - 1 / x**2) + assert sin(atan2(y, x)) == y / sqrt(x**2 + y**2) + + assert sin(pi*I) == sinh(pi)*I + assert sin(-pi*I) == -sinh(pi)*I + assert sin(-2*I) == -sinh(2)*I + + assert sin(pi) == 0 + assert sin(-pi) == 0 + assert sin(2*pi) == 0 + assert sin(-2*pi) == 0 + assert sin(-3*10**73*pi) == 0 + assert sin(7*10**103*pi) == 0 + + assert sin(pi/2) == 1 + assert sin(-pi/2) == -1 + assert sin(pi*Rational(5, 2)) == 1 + assert sin(pi*Rational(7, 2)) == -1 + + ne = symbols('ne', integer=True, even=False) + e = symbols('e', even=True) + assert sin(pi*ne/2) == (-1)**(ne/2 - S.Half) + assert sin(pi*k/2).func == sin + assert sin(pi*e/2) == 0 + assert sin(pi*k) == 0 + assert sin(pi*k).subs(k, 3) == sin(pi*k/2).subs(k, 6) # issue 8298 + + assert sin(pi/3) == S.Half*sqrt(3) + assert sin(pi*Rational(-2, 3)) == Rational(-1, 2)*sqrt(3) + + assert sin(pi/4) == S.Half*sqrt(2) + assert sin(-pi/4) == Rational(-1, 2)*sqrt(2) + assert sin(pi*Rational(17, 4)) == S.Half*sqrt(2) + assert sin(pi*Rational(-3, 4)) == Rational(-1, 2)*sqrt(2) + + assert sin(pi/6) == S.Half + assert sin(-pi/6) == Rational(-1, 2) + assert sin(pi*Rational(7, 6)) == Rational(-1, 2) + assert sin(pi*Rational(-5, 6)) == Rational(-1, 2) + + assert sin(pi*Rational(1, 5)) == sqrt((5 - sqrt(5)) / 8) + assert sin(pi*Rational(2, 5)) == sqrt((5 + sqrt(5)) / 8) + assert sin(pi*Rational(3, 5)) == sin(pi*Rational(2, 5)) + assert sin(pi*Rational(4, 5)) == sin(pi*Rational(1, 5)) + assert sin(pi*Rational(6, 5)) == -sin(pi*Rational(1, 5)) + assert sin(pi*Rational(8, 5)) == -sin(pi*Rational(2, 5)) + + assert sin(pi*Rational(-1273, 5)) == -sin(pi*Rational(2, 5)) + + assert sin(pi/8) == sqrt((2 - sqrt(2))/4) + + assert sin(pi/10) == Rational(-1, 4) + sqrt(5)/4 + + assert sin(pi/12) == -sqrt(2)/4 + sqrt(6)/4 + assert sin(pi*Rational(5, 12)) == sqrt(2)/4 + sqrt(6)/4 + assert sin(pi*Rational(-7, 12)) == -sqrt(2)/4 - sqrt(6)/4 + assert sin(pi*Rational(-11, 12)) == sqrt(2)/4 - sqrt(6)/4 + + assert sin(pi*Rational(104, 105)) == sin(pi/105) + assert sin(pi*Rational(106, 105)) == -sin(pi/105) + + assert sin(pi*Rational(-104, 105)) == -sin(pi/105) + assert sin(pi*Rational(-106, 105)) == sin(pi/105) + + assert sin(x*I) == sinh(x)*I + + assert sin(k*pi) == 0 + assert sin(17*k*pi) == 0 + assert sin(2*k*pi + 4) == sin(4) + assert sin(2*k*pi + m*pi + 1) == (-1)**(m + 2*k)*sin(1) + + assert sin(k*pi*I) == sinh(k*pi)*I + + assert sin(r).is_real is True + + assert sin(0, evaluate=False).is_algebraic + assert sin(a).is_algebraic is None + assert sin(na).is_algebraic is False + q = Symbol('q', rational=True) + assert sin(pi*q).is_algebraic + qn = Symbol('qn', rational=True, nonzero=True) + assert sin(qn).is_rational is False + assert sin(q).is_rational is None # issue 8653 + + assert isinstance(sin( re(x) - im(y)), sin) is True + assert isinstance(sin(-re(x) + im(y)), sin) is False + + assert sin(SetExpr(Interval(0, 1))) == SetExpr(ImageSet(Lambda(x, sin(x)), + Interval(0, 1))) + + for d in list(range(1, 22)) + [60, 85]: + for n in range(d*2 + 1): + x = n*pi/d + e = abs( float(sin(x)) - sin(float(x)) ) + assert e < 1e-12 + + assert sin(0, evaluate=False).is_zero is True + assert sin(k*pi, evaluate=False).is_zero is True + + assert sin(Add(1, -1, evaluate=False), evaluate=False).is_zero is True + + +def test_sin_cos(): + for d in [1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 24, 30, 40, 60, 120]: # list is not exhaustive... + for n in range(-2*d, d*2): + x = n*pi/d + assert sin(x + pi/2) == cos(x), "fails for %d*pi/%d" % (n, d) + assert sin(x - pi/2) == -cos(x), "fails for %d*pi/%d" % (n, d) + assert sin(x) == cos(x - pi/2), "fails for %d*pi/%d" % (n, d) + assert -sin(x) == cos(x + pi/2), "fails for %d*pi/%d" % (n, d) + + +def test_sin_series(): + assert sin(x).series(x, 0, 9) == \ + x - x**3/6 + x**5/120 - x**7/5040 + O(x**9) + + +def test_sin_rewrite(): + assert sin(x).rewrite(exp) == -I*(exp(I*x) - exp(-I*x))/2 + assert sin(x).rewrite(tan) == 2*tan(x/2)/(1 + tan(x/2)**2) + assert sin(x).rewrite(cot) == \ + Piecewise((0, Eq(im(x), 0) & Eq(Mod(x, pi), 0)), + (2*cot(x/2)/(cot(x/2)**2 + 1), True)) + assert sin(sinh(x)).rewrite( + exp).subs(x, 3).n() == sin(x).rewrite(exp).subs(x, sinh(3)).n() + assert sin(cosh(x)).rewrite( + exp).subs(x, 3).n() == sin(x).rewrite(exp).subs(x, cosh(3)).n() + assert sin(tanh(x)).rewrite( + exp).subs(x, 3).n() == sin(x).rewrite(exp).subs(x, tanh(3)).n() + assert sin(coth(x)).rewrite( + exp).subs(x, 3).n() == sin(x).rewrite(exp).subs(x, coth(3)).n() + assert sin(sin(x)).rewrite( + exp).subs(x, 3).n() == sin(x).rewrite(exp).subs(x, sin(3)).n() + assert sin(cos(x)).rewrite( + exp).subs(x, 3).n() == sin(x).rewrite(exp).subs(x, cos(3)).n() + assert sin(tan(x)).rewrite( + exp).subs(x, 3).n() == sin(x).rewrite(exp).subs(x, tan(3)).n() + assert sin(cot(x)).rewrite( + exp).subs(x, 3).n() == sin(x).rewrite(exp).subs(x, cot(3)).n() + assert sin(log(x)).rewrite(Pow) == I*x**-I / 2 - I*x**I /2 + assert sin(x).rewrite(csc) == 1/csc(x) + assert sin(x).rewrite(cos) == cos(x - pi / 2, evaluate=False) + assert sin(x).rewrite(sec) == 1 / sec(x - pi / 2, evaluate=False) + assert sin(cos(x)).rewrite(Pow) == sin(cos(x)) + assert sin(x).rewrite(besselj) == sqrt(pi*x/2)*besselj(S.Half, x) + assert sin(x).rewrite(besselj).subs(x, 0) == sin(0) + + +def _test_extrig(f, i, e): + from sympy.core.function import expand_trig + assert unchanged(f, i) + assert expand_trig(f(i)) == f(i) + # testing directly instead of with .expand(trig=True) + # because the other expansions undo the unevaluated Mul + assert expand_trig(f(Mul(i, 1, evaluate=False))) == e + assert abs(f(i) - e).n() < 1e-10 + + +def test_sin_expansion(): + # Note: these formulas are not unique. The ones here come from the + # Chebyshev formulas. + assert sin(x + y).expand(trig=True) == sin(x)*cos(y) + cos(x)*sin(y) + assert sin(x - y).expand(trig=True) == sin(x)*cos(y) - cos(x)*sin(y) + assert sin(y - x).expand(trig=True) == cos(x)*sin(y) - sin(x)*cos(y) + assert sin(2*x).expand(trig=True) == 2*sin(x)*cos(x) + assert sin(3*x).expand(trig=True) == -4*sin(x)**3 + 3*sin(x) + assert sin(4*x).expand(trig=True) == -8*sin(x)**3*cos(x) + 4*sin(x)*cos(x) + assert sin(2*pi/17).expand(trig=True) == sin(2*pi/17, evaluate=False) + assert sin(x+pi/17).expand(trig=True) == sin(pi/17)*cos(x) + cos(pi/17)*sin(x) + _test_extrig(sin, 2, 2*sin(1)*cos(1)) + _test_extrig(sin, 3, -4*sin(1)**3 + 3*sin(1)) + + +def test_sin_AccumBounds(): + assert sin(AccumBounds(-oo, oo)) == AccumBounds(-1, 1) + assert sin(AccumBounds(0, oo)) == AccumBounds(-1, 1) + assert sin(AccumBounds(-oo, 0)) == AccumBounds(-1, 1) + assert sin(AccumBounds(0, 2*S.Pi)) == AccumBounds(-1, 1) + assert sin(AccumBounds(0, S.Pi*Rational(3, 4))) == AccumBounds(0, 1) + assert sin(AccumBounds(S.Pi*Rational(3, 4), S.Pi*Rational(7, 4))) == AccumBounds(-1, sin(S.Pi*Rational(3, 4))) + assert sin(AccumBounds(S.Pi/4, S.Pi/3)) == AccumBounds(sin(S.Pi/4), sin(S.Pi/3)) + assert sin(AccumBounds(S.Pi*Rational(3, 4), S.Pi*Rational(5, 6))) == AccumBounds(sin(S.Pi*Rational(5, 6)), sin(S.Pi*Rational(3, 4))) + + +def test_sin_fdiff(): + assert sin(x).fdiff() == cos(x) + raises(ArgumentIndexError, lambda: sin(x).fdiff(2)) + + +def test_trig_symmetry(): + assert sin(-x) == -sin(x) + assert cos(-x) == cos(x) + assert tan(-x) == -tan(x) + assert cot(-x) == -cot(x) + assert sin(x + pi) == -sin(x) + assert sin(x + 2*pi) == sin(x) + assert sin(x + 3*pi) == -sin(x) + assert sin(x + 4*pi) == sin(x) + assert sin(x - 5*pi) == -sin(x) + assert cos(x + pi) == -cos(x) + assert cos(x + 2*pi) == cos(x) + assert cos(x + 3*pi) == -cos(x) + assert cos(x + 4*pi) == cos(x) + assert cos(x - 5*pi) == -cos(x) + assert tan(x + pi) == tan(x) + assert tan(x - 3*pi) == tan(x) + assert cot(x + pi) == cot(x) + assert cot(x - 3*pi) == cot(x) + assert sin(pi/2 - x) == cos(x) + assert sin(pi*Rational(3, 2) - x) == -cos(x) + assert sin(pi*Rational(5, 2) - x) == cos(x) + assert cos(pi/2 - x) == sin(x) + assert cos(pi*Rational(3, 2) - x) == -sin(x) + assert cos(pi*Rational(5, 2) - x) == sin(x) + assert tan(pi/2 - x) == cot(x) + assert tan(pi*Rational(3, 2) - x) == cot(x) + assert tan(pi*Rational(5, 2) - x) == cot(x) + assert cot(pi/2 - x) == tan(x) + assert cot(pi*Rational(3, 2) - x) == tan(x) + assert cot(pi*Rational(5, 2) - x) == tan(x) + assert sin(pi/2 + x) == cos(x) + assert cos(pi/2 + x) == -sin(x) + assert tan(pi/2 + x) == -cot(x) + assert cot(pi/2 + x) == -tan(x) + + +def test_cos(): + x, y = symbols('x y') + + assert cos.nargs == FiniteSet(1) + assert cos(nan) is nan + + assert cos(oo) == AccumBounds(-1, 1) + assert cos(oo) - cos(oo) == AccumBounds(-2, 2) + assert cos(oo*I) is oo + assert cos(-oo*I) is oo + assert cos(zoo) is nan + + assert cos(0) == 1 + + assert cos(acos(x)) == x + assert cos(atan(x)) == 1 / sqrt(1 + x**2) + assert cos(asin(x)) == sqrt(1 - x**2) + assert cos(acot(x)) == 1 / sqrt(1 + 1 / x**2) + assert cos(acsc(x)) == sqrt(1 - 1 / x**2) + assert cos(asec(x)) == 1 / x + assert cos(atan2(y, x)) == x / sqrt(x**2 + y**2) + + assert cos(pi*I) == cosh(pi) + assert cos(-pi*I) == cosh(pi) + assert cos(-2*I) == cosh(2) + + assert cos(pi/2) == 0 + assert cos(-pi/2) == 0 + assert cos(pi/2) == 0 + assert cos(-pi/2) == 0 + assert cos((-3*10**73 + 1)*pi/2) == 0 + assert cos((7*10**103 + 1)*pi/2) == 0 + + n = symbols('n', integer=True, even=False) + e = symbols('e', even=True) + assert cos(pi*n/2) == 0 + assert cos(pi*e/2) == (-1)**(e/2) + + assert cos(pi) == -1 + assert cos(-pi) == -1 + assert cos(2*pi) == 1 + assert cos(5*pi) == -1 + assert cos(8*pi) == 1 + + assert cos(pi/3) == S.Half + assert cos(pi*Rational(-2, 3)) == Rational(-1, 2) + + assert cos(pi/4) == S.Half*sqrt(2) + assert cos(-pi/4) == S.Half*sqrt(2) + assert cos(pi*Rational(11, 4)) == Rational(-1, 2)*sqrt(2) + assert cos(pi*Rational(-3, 4)) == Rational(-1, 2)*sqrt(2) + + assert cos(pi/6) == S.Half*sqrt(3) + assert cos(-pi/6) == S.Half*sqrt(3) + assert cos(pi*Rational(7, 6)) == Rational(-1, 2)*sqrt(3) + assert cos(pi*Rational(-5, 6)) == Rational(-1, 2)*sqrt(3) + + assert cos(pi*Rational(1, 5)) == (sqrt(5) + 1)/4 + assert cos(pi*Rational(2, 5)) == (sqrt(5) - 1)/4 + assert cos(pi*Rational(3, 5)) == -cos(pi*Rational(2, 5)) + assert cos(pi*Rational(4, 5)) == -cos(pi*Rational(1, 5)) + assert cos(pi*Rational(6, 5)) == -cos(pi*Rational(1, 5)) + assert cos(pi*Rational(8, 5)) == cos(pi*Rational(2, 5)) + + assert cos(pi*Rational(-1273, 5)) == -cos(pi*Rational(2, 5)) + + assert cos(pi/8) == sqrt((2 + sqrt(2))/4) + + assert cos(pi/12) == sqrt(2)/4 + sqrt(6)/4 + assert cos(pi*Rational(5, 12)) == -sqrt(2)/4 + sqrt(6)/4 + assert cos(pi*Rational(7, 12)) == sqrt(2)/4 - sqrt(6)/4 + assert cos(pi*Rational(11, 12)) == -sqrt(2)/4 - sqrt(6)/4 + + assert cos(pi*Rational(104, 105)) == -cos(pi/105) + assert cos(pi*Rational(106, 105)) == -cos(pi/105) + + assert cos(pi*Rational(-104, 105)) == -cos(pi/105) + assert cos(pi*Rational(-106, 105)) == -cos(pi/105) + + assert cos(x*I) == cosh(x) + assert cos(k*pi*I) == cosh(k*pi) + + assert cos(r).is_real is True + + assert cos(0, evaluate=False).is_algebraic + assert cos(a).is_algebraic is None + assert cos(na).is_algebraic is False + q = Symbol('q', rational=True) + assert cos(pi*q).is_algebraic + assert cos(pi*Rational(2, 7)).is_algebraic + + assert cos(k*pi) == (-1)**k + assert cos(2*k*pi) == 1 + assert cos(0, evaluate=False).is_zero is False + assert cos(Rational(1, 2)).is_zero is False + # The following test will return None as the result, but really it should + # be True even if it is not always possible to resolve an assumptions query. + assert cos(asin(-1, evaluate=False), evaluate=False).is_zero is None + for d in list(range(1, 22)) + [60, 85]: + for n in range(2*d + 1): + x = n*pi/d + e = abs( float(cos(x)) - cos(float(x)) ) + assert e < 1e-12 + + +def test_issue_6190(): + c = Float('123456789012345678901234567890.25', '') + for cls in [sin, cos, tan, cot]: + assert cls(c*pi) == cls(pi/4) + assert cls(4.125*pi) == cls(pi/8) + assert cls(4.7*pi) == cls((4.7 % 2)*pi) + + +def test_cos_series(): + assert cos(x).series(x, 0, 9) == \ + 1 - x**2/2 + x**4/24 - x**6/720 + x**8/40320 + O(x**9) + + +def test_cos_rewrite(): + assert cos(x).rewrite(exp) == exp(I*x)/2 + exp(-I*x)/2 + assert cos(x).rewrite(tan) == (1 - tan(x/2)**2)/(1 + tan(x/2)**2) + assert cos(x).rewrite(cot) == \ + Piecewise((1, Eq(im(x), 0) & Eq(Mod(x, 2*pi), 0)), + ((cot(x/2)**2 - 1)/(cot(x/2)**2 + 1), True)) + assert cos(sinh(x)).rewrite( + exp).subs(x, 3).n() == cos(x).rewrite(exp).subs(x, sinh(3)).n() + assert cos(cosh(x)).rewrite( + exp).subs(x, 3).n() == cos(x).rewrite(exp).subs(x, cosh(3)).n() + assert cos(tanh(x)).rewrite( + exp).subs(x, 3).n() == cos(x).rewrite(exp).subs(x, tanh(3)).n() + assert cos(coth(x)).rewrite( + exp).subs(x, 3).n() == cos(x).rewrite(exp).subs(x, coth(3)).n() + assert cos(sin(x)).rewrite( + exp).subs(x, 3).n() == cos(x).rewrite(exp).subs(x, sin(3)).n() + assert cos(cos(x)).rewrite( + exp).subs(x, 3).n() == cos(x).rewrite(exp).subs(x, cos(3)).n() + assert cos(tan(x)).rewrite( + exp).subs(x, 3).n() == cos(x).rewrite(exp).subs(x, tan(3)).n() + assert cos(cot(x)).rewrite( + exp).subs(x, 3).n() == cos(x).rewrite(exp).subs(x, cot(3)).n() + assert cos(log(x)).rewrite(Pow) == x**I/2 + x**-I/2 + assert cos(x).rewrite(sec) == 1/sec(x) + assert cos(x).rewrite(sin) == sin(x + pi/2, evaluate=False) + assert cos(x).rewrite(csc) == 1/csc(-x + pi/2, evaluate=False) + assert cos(sin(x)).rewrite(Pow) == cos(sin(x)) + assert cos(x).rewrite(besselj) == Piecewise( + (sqrt(pi*x/2)*besselj(-S.Half, x), Ne(x, 0)), + (1, True) + ) + assert cos(x).rewrite(besselj).subs(x, 0) == cos(0) + + +def test_cos_expansion(): + assert cos(x + y).expand(trig=True) == cos(x)*cos(y) - sin(x)*sin(y) + assert cos(x - y).expand(trig=True) == cos(x)*cos(y) + sin(x)*sin(y) + assert cos(y - x).expand(trig=True) == cos(x)*cos(y) + sin(x)*sin(y) + assert cos(2*x).expand(trig=True) == 2*cos(x)**2 - 1 + assert cos(3*x).expand(trig=True) == 4*cos(x)**3 - 3*cos(x) + assert cos(4*x).expand(trig=True) == 8*cos(x)**4 - 8*cos(x)**2 + 1 + assert cos(2*pi/17).expand(trig=True) == cos(2*pi/17, evaluate=False) + assert cos(x+pi/17).expand(trig=True) == cos(pi/17)*cos(x) - sin(pi/17)*sin(x) + _test_extrig(cos, 2, 2*cos(1)**2 - 1) + _test_extrig(cos, 3, 4*cos(1)**3 - 3*cos(1)) + + +def test_cos_AccumBounds(): + assert cos(AccumBounds(-oo, oo)) == AccumBounds(-1, 1) + assert cos(AccumBounds(0, oo)) == AccumBounds(-1, 1) + assert cos(AccumBounds(-oo, 0)) == AccumBounds(-1, 1) + assert cos(AccumBounds(0, 2*S.Pi)) == AccumBounds(-1, 1) + assert cos(AccumBounds(-S.Pi/3, S.Pi/4)) == AccumBounds(cos(-S.Pi/3), 1) + assert cos(AccumBounds(S.Pi*Rational(3, 4), S.Pi*Rational(5, 4))) == AccumBounds(-1, cos(S.Pi*Rational(3, 4))) + assert cos(AccumBounds(S.Pi*Rational(5, 4), S.Pi*Rational(4, 3))) == AccumBounds(cos(S.Pi*Rational(5, 4)), cos(S.Pi*Rational(4, 3))) + assert cos(AccumBounds(S.Pi/4, S.Pi/3)) == AccumBounds(cos(S.Pi/3), cos(S.Pi/4)) + + +def test_cos_fdiff(): + assert cos(x).fdiff() == -sin(x) + raises(ArgumentIndexError, lambda: cos(x).fdiff(2)) + + +def test_tan(): + assert tan(nan) is nan + + assert tan(zoo) is nan + assert tan(oo) == AccumBounds(-oo, oo) + assert tan(oo) - tan(oo) == AccumBounds(-oo, oo) + assert tan.nargs == FiniteSet(1) + assert tan(oo*I) == I + assert tan(-oo*I) == -I + + assert tan(0) == 0 + + assert tan(atan(x)) == x + assert tan(asin(x)) == x / sqrt(1 - x**2) + assert tan(acos(x)) == sqrt(1 - x**2) / x + assert tan(acot(x)) == 1 / x + assert tan(acsc(x)) == 1 / (sqrt(1 - 1 / x**2) * x) + assert tan(asec(x)) == sqrt(1 - 1 / x**2) * x + assert tan(atan2(y, x)) == y/x + + assert tan(pi*I) == tanh(pi)*I + assert tan(-pi*I) == -tanh(pi)*I + assert tan(-2*I) == -tanh(2)*I + + assert tan(pi) == 0 + assert tan(-pi) == 0 + assert tan(2*pi) == 0 + assert tan(-2*pi) == 0 + assert tan(-3*10**73*pi) == 0 + + assert tan(pi/2) is zoo + assert tan(pi*Rational(3, 2)) is zoo + + assert tan(pi/3) == sqrt(3) + assert tan(pi*Rational(-2, 3)) == sqrt(3) + + assert tan(pi/4) is S.One + assert tan(-pi/4) is S.NegativeOne + assert tan(pi*Rational(17, 4)) is S.One + assert tan(pi*Rational(-3, 4)) is S.One + + assert tan(pi/5) == sqrt(5 - 2*sqrt(5)) + assert tan(pi*Rational(2, 5)) == sqrt(5 + 2*sqrt(5)) + assert tan(pi*Rational(18, 5)) == -sqrt(5 + 2*sqrt(5)) + assert tan(pi*Rational(-16, 5)) == -sqrt(5 - 2*sqrt(5)) + + assert tan(pi/6) == 1/sqrt(3) + assert tan(-pi/6) == -1/sqrt(3) + assert tan(pi*Rational(7, 6)) == 1/sqrt(3) + assert tan(pi*Rational(-5, 6)) == 1/sqrt(3) + + assert tan(pi/8) == -1 + sqrt(2) + assert tan(pi*Rational(3, 8)) == 1 + sqrt(2) # issue 15959 + assert tan(pi*Rational(5, 8)) == -1 - sqrt(2) + assert tan(pi*Rational(7, 8)) == 1 - sqrt(2) + + assert tan(pi/10) == sqrt(1 - 2*sqrt(5)/5) + assert tan(pi*Rational(3, 10)) == sqrt(1 + 2*sqrt(5)/5) + assert tan(pi*Rational(17, 10)) == -sqrt(1 + 2*sqrt(5)/5) + assert tan(pi*Rational(-31, 10)) == -sqrt(1 - 2*sqrt(5)/5) + + assert tan(pi/12) == -sqrt(3) + 2 + assert tan(pi*Rational(5, 12)) == sqrt(3) + 2 + assert tan(pi*Rational(7, 12)) == -sqrt(3) - 2 + assert tan(pi*Rational(11, 12)) == sqrt(3) - 2 + + assert tan(pi/24).radsimp() == -2 - sqrt(3) + sqrt(2) + sqrt(6) + assert tan(pi*Rational(5, 24)).radsimp() == -2 + sqrt(3) - sqrt(2) + sqrt(6) + assert tan(pi*Rational(7, 24)).radsimp() == 2 - sqrt(3) - sqrt(2) + sqrt(6) + assert tan(pi*Rational(11, 24)).radsimp() == 2 + sqrt(3) + sqrt(2) + sqrt(6) + assert tan(pi*Rational(13, 24)).radsimp() == -2 - sqrt(3) - sqrt(2) - sqrt(6) + assert tan(pi*Rational(17, 24)).radsimp() == -2 + sqrt(3) + sqrt(2) - sqrt(6) + assert tan(pi*Rational(19, 24)).radsimp() == 2 - sqrt(3) + sqrt(2) - sqrt(6) + assert tan(pi*Rational(23, 24)).radsimp() == 2 + sqrt(3) - sqrt(2) - sqrt(6) + + assert tan(x*I) == tanh(x)*I + + assert tan(k*pi) == 0 + assert tan(17*k*pi) == 0 + + assert tan(k*pi*I) == tanh(k*pi)*I + + assert tan(r).is_real is None + assert tan(r).is_extended_real is True + + assert tan(0, evaluate=False).is_algebraic + assert tan(a).is_algebraic is None + assert tan(na).is_algebraic is False + + assert tan(pi*Rational(10, 7)) == tan(pi*Rational(3, 7)) + assert tan(pi*Rational(11, 7)) == -tan(pi*Rational(3, 7)) + assert tan(pi*Rational(-11, 7)) == tan(pi*Rational(3, 7)) + + assert tan(pi*Rational(15, 14)) == tan(pi/14) + assert tan(pi*Rational(-15, 14)) == -tan(pi/14) + + assert tan(r).is_finite is None + assert tan(I*r).is_finite is True + + # https://github.com/sympy/sympy/issues/21177 + f = tan(pi*(x + S(3)/2))/(3*x) + assert f.as_leading_term(x) == -1/(3*pi*x**2) + + +def test_tan_series(): + assert tan(x).series(x, 0, 9) == \ + x + x**3/3 + 2*x**5/15 + 17*x**7/315 + O(x**9) + + +def test_tan_rewrite(): + neg_exp, pos_exp = exp(-x*I), exp(x*I) + assert tan(x).rewrite(exp) == I*(neg_exp - pos_exp)/(neg_exp + pos_exp) + assert tan(x).rewrite(sin) == 2*sin(x)**2/sin(2*x) + assert tan(x).rewrite(cos) == cos(x - S.Pi/2, evaluate=False)/cos(x) + assert tan(x).rewrite(cot) == 1/cot(x) + assert tan(sinh(x)).rewrite(exp).subs(x, 3).n() == tan(x).rewrite(exp).subs(x, sinh(3)).n() + assert tan(cosh(x)).rewrite(exp).subs(x, 3).n() == tan(x).rewrite(exp).subs(x, cosh(3)).n() + assert tan(tanh(x)).rewrite(exp).subs(x, 3).n() == tan(x).rewrite(exp).subs(x, tanh(3)).n() + assert tan(coth(x)).rewrite(exp).subs(x, 3).n() == tan(x).rewrite(exp).subs(x, coth(3)).n() + assert tan(sin(x)).rewrite(exp).subs(x, 3).n() == tan(x).rewrite(exp).subs(x, sin(3)).n() + assert tan(cos(x)).rewrite(exp).subs(x, 3).n() == tan(x).rewrite(exp).subs(x, cos(3)).n() + assert tan(tan(x)).rewrite(exp).subs(x, 3).n() == tan(x).rewrite(exp).subs(x, tan(3)).n() + assert tan(cot(x)).rewrite(exp).subs(x, 3).n() == tan(x).rewrite(exp).subs(x, cot(3)).n() + assert tan(log(x)).rewrite(Pow) == I*(x**-I - x**I)/(x**-I + x**I) + assert tan(x).rewrite(sec) == sec(x)/sec(x - pi/2, evaluate=False) + assert tan(x).rewrite(csc) == csc(-x + pi/2, evaluate=False)/csc(x) + assert tan(sin(x)).rewrite(Pow) == tan(sin(x)) + assert tan(pi*Rational(2, 5), evaluate=False).rewrite(sqrt) == sqrt(sqrt(5)/8 + + Rational(5, 8))/(Rational(-1, 4) + sqrt(5)/4) + assert tan(x).rewrite(besselj) == besselj(S.Half, x)/besselj(-S.Half, x) + assert tan(x).rewrite(besselj).subs(x, 0) == tan(0) + + +@slow +def test_tan_rewrite_slow(): + assert 0 == (cos(pi/34)*tan(pi/34) - sin(pi/34)).rewrite(pow) + assert 0 == (cos(pi/17)*tan(pi/17) - sin(pi/17)).rewrite(pow) + assert tan(pi/19).rewrite(pow) == tan(pi/19) + assert tan(pi*Rational(8, 19)).rewrite(sqrt) == tan(pi*Rational(8, 19)) + assert tan(pi*Rational(2, 5), evaluate=False).rewrite(sqrt) == sqrt(sqrt(5)/8 + + Rational(5, 8))/(Rational(-1, 4) + sqrt(5)/4) + + +def test_tan_subs(): + assert tan(x).subs(tan(x), y) == y + assert tan(x).subs(x, y) == tan(y) + assert tan(x).subs(x, S.Pi/2) is zoo + assert tan(x).subs(x, S.Pi*Rational(3, 2)) is zoo + + +def test_tan_expansion(): + assert tan(x + y).expand(trig=True) == ((tan(x) + tan(y))/(1 - tan(x)*tan(y))).expand() + assert tan(x - y).expand(trig=True) == ((tan(x) - tan(y))/(1 + tan(x)*tan(y))).expand() + assert tan(x + y + z).expand(trig=True) == ( + (tan(x) + tan(y) + tan(z) - tan(x)*tan(y)*tan(z))/ + (1 - tan(x)*tan(y) - tan(x)*tan(z) - tan(y)*tan(z))).expand() + assert 0 == tan(2*x).expand(trig=True).rewrite(tan).subs([(tan(x), Rational(1, 7))])*24 - 7 + assert 0 == tan(3*x).expand(trig=True).rewrite(tan).subs([(tan(x), Rational(1, 5))])*55 - 37 + assert 0 == tan(4*x - pi/4).expand(trig=True).rewrite(tan).subs([(tan(x), Rational(1, 5))])*239 - 1 + _test_extrig(tan, 2, 2*tan(1)/(1 - tan(1)**2)) + _test_extrig(tan, 3, (-tan(1)**3 + 3*tan(1))/(1 - 3*tan(1)**2)) + + +def test_tan_AccumBounds(): + assert tan(AccumBounds(-oo, oo)) == AccumBounds(-oo, oo) + assert tan(AccumBounds(S.Pi/3, S.Pi*Rational(2, 3))) == AccumBounds(-oo, oo) + assert tan(AccumBounds(S.Pi/6, S.Pi/3)) == AccumBounds(tan(S.Pi/6), tan(S.Pi/3)) + + +def test_tan_fdiff(): + assert tan(x).fdiff() == tan(x)**2 + 1 + raises(ArgumentIndexError, lambda: tan(x).fdiff(2)) + + +def test_cot(): + assert cot(nan) is nan + + assert cot.nargs == FiniteSet(1) + assert cot(oo*I) == -I + assert cot(-oo*I) == I + assert cot(zoo) is nan + + assert cot(0) is zoo + assert cot(2*pi) is zoo + + assert cot(acot(x)) == x + assert cot(atan(x)) == 1 / x + assert cot(asin(x)) == sqrt(1 - x**2) / x + assert cot(acos(x)) == x / sqrt(1 - x**2) + assert cot(acsc(x)) == sqrt(1 - 1 / x**2) * x + assert cot(asec(x)) == 1 / (sqrt(1 - 1 / x**2) * x) + assert cot(atan2(y, x)) == x/y + + assert cot(pi*I) == -coth(pi)*I + assert cot(-pi*I) == coth(pi)*I + assert cot(-2*I) == coth(2)*I + + assert cot(pi) == cot(2*pi) == cot(3*pi) + assert cot(-pi) == cot(-2*pi) == cot(-3*pi) + + assert cot(pi/2) == 0 + assert cot(-pi/2) == 0 + assert cot(pi*Rational(5, 2)) == 0 + assert cot(pi*Rational(7, 2)) == 0 + + assert cot(pi/3) == 1/sqrt(3) + assert cot(pi*Rational(-2, 3)) == 1/sqrt(3) + + assert cot(pi/4) is S.One + assert cot(-pi/4) is S.NegativeOne + assert cot(pi*Rational(17, 4)) is S.One + assert cot(pi*Rational(-3, 4)) is S.One + + assert cot(pi/6) == sqrt(3) + assert cot(-pi/6) == -sqrt(3) + assert cot(pi*Rational(7, 6)) == sqrt(3) + assert cot(pi*Rational(-5, 6)) == sqrt(3) + + assert cot(pi/8) == 1 + sqrt(2) + assert cot(pi*Rational(3, 8)) == -1 + sqrt(2) + assert cot(pi*Rational(5, 8)) == 1 - sqrt(2) + assert cot(pi*Rational(7, 8)) == -1 - sqrt(2) + + assert cot(pi/12) == sqrt(3) + 2 + assert cot(pi*Rational(5, 12)) == -sqrt(3) + 2 + assert cot(pi*Rational(7, 12)) == sqrt(3) - 2 + assert cot(pi*Rational(11, 12)) == -sqrt(3) - 2 + + assert cot(pi/24).radsimp() == sqrt(2) + sqrt(3) + 2 + sqrt(6) + assert cot(pi*Rational(5, 24)).radsimp() == -sqrt(2) - sqrt(3) + 2 + sqrt(6) + assert cot(pi*Rational(7, 24)).radsimp() == -sqrt(2) + sqrt(3) - 2 + sqrt(6) + assert cot(pi*Rational(11, 24)).radsimp() == sqrt(2) - sqrt(3) - 2 + sqrt(6) + assert cot(pi*Rational(13, 24)).radsimp() == -sqrt(2) + sqrt(3) + 2 - sqrt(6) + assert cot(pi*Rational(17, 24)).radsimp() == sqrt(2) - sqrt(3) + 2 - sqrt(6) + assert cot(pi*Rational(19, 24)).radsimp() == sqrt(2) + sqrt(3) - 2 - sqrt(6) + assert cot(pi*Rational(23, 24)).radsimp() == -sqrt(2) - sqrt(3) - 2 - sqrt(6) + + assert cot(x*I) == -coth(x)*I + assert cot(k*pi*I) == -coth(k*pi)*I + + assert cot(r).is_real is None + assert cot(r).is_extended_real is True + + assert cot(a).is_algebraic is None + assert cot(na).is_algebraic is False + + assert cot(pi*Rational(10, 7)) == cot(pi*Rational(3, 7)) + assert cot(pi*Rational(11, 7)) == -cot(pi*Rational(3, 7)) + assert cot(pi*Rational(-11, 7)) == cot(pi*Rational(3, 7)) + + assert cot(pi*Rational(39, 34)) == cot(pi*Rational(5, 34)) + assert cot(pi*Rational(-41, 34)) == -cot(pi*Rational(7, 34)) + + assert cot(x).is_finite is None + assert cot(r).is_finite is None + i = Symbol('i', imaginary=True) + assert cot(i).is_finite is True + + assert cot(x).subs(x, 3*pi) is zoo + + # https://github.com/sympy/sympy/issues/21177 + f = cot(pi*(x + 4))/(3*x) + assert f.as_leading_term(x) == 1/(3*pi*x**2) + + +def test_tan_cot_sin_cos_evalf(): + assert abs((tan(pi*Rational(8, 15))*cos(pi*Rational(8, 15))/sin(pi*Rational(8, 15)) - 1).evalf()) < 1e-14 + assert abs((cot(pi*Rational(4, 15))*sin(pi*Rational(4, 15))/cos(pi*Rational(4, 15)) - 1).evalf()) < 1e-14 + +@XFAIL +def test_tan_cot_sin_cos_ratsimp(): + assert 1 == (tan(pi*Rational(8, 15))*cos(pi*Rational(8, 15))/sin(pi*Rational(8, 15))).ratsimp() + assert 1 == (cot(pi*Rational(4, 15))*sin(pi*Rational(4, 15))/cos(pi*Rational(4, 15))).ratsimp() + + +def test_cot_series(): + assert cot(x).series(x, 0, 9) == \ + 1/x - x/3 - x**3/45 - 2*x**5/945 - x**7/4725 + O(x**9) + # issue 6210 + assert cot(x**4 + x**5).series(x, 0, 1) == \ + x**(-4) - 1/x**3 + x**(-2) - 1/x + 1 + O(x) + assert cot(pi*(1-x)).series(x, 0, 3) == -1/(pi*x) + pi*x/3 + O(x**3) + assert cot(x).taylor_term(0, x) == 1/x + assert cot(x).taylor_term(2, x) is S.Zero + assert cot(x).taylor_term(3, x) == -x**3/45 + + +def test_cot_rewrite(): + neg_exp, pos_exp = exp(-x*I), exp(x*I) + assert cot(x).rewrite(exp) == I*(pos_exp + neg_exp)/(pos_exp - neg_exp) + assert cot(x).rewrite(sin) == sin(2*x)/(2*(sin(x)**2)) + assert cot(x).rewrite(cos) == cos(x)/cos(x - pi/2, evaluate=False) + assert cot(x).rewrite(tan) == 1/tan(x) + def check(func): + z = cot(func(x)).rewrite(exp) - cot(x).rewrite(exp).subs(x, func(x)) + assert z.rewrite(exp).expand() == 0 + check(sinh) + check(cosh) + check(tanh) + check(coth) + check(sin) + check(cos) + check(tan) + assert cot(log(x)).rewrite(Pow) == -I*(x**-I + x**I)/(x**-I - x**I) + assert cot(x).rewrite(sec) == sec(x - pi / 2, evaluate=False) / sec(x) + assert cot(x).rewrite(csc) == csc(x) / csc(- x + pi / 2, evaluate=False) + assert cot(sin(x)).rewrite(Pow) == cot(sin(x)) + assert cot(pi*Rational(2, 5), evaluate=False).rewrite(sqrt) == (Rational(-1, 4) + sqrt(5)/4)/\ + sqrt(sqrt(5)/8 + Rational(5, 8)) + assert cot(x).rewrite(besselj) == besselj(-S.Half, x)/besselj(S.Half, x) + assert cot(x).rewrite(besselj).subs(x, 0) == cot(0) + + +@slow +def test_cot_rewrite_slow(): + assert cot(pi*Rational(4, 34)).rewrite(pow).ratsimp() == \ + (cos(pi*Rational(4, 34))/sin(pi*Rational(4, 34))).rewrite(pow).ratsimp() + assert cot(pi*Rational(4, 17)).rewrite(pow) == \ + (cos(pi*Rational(4, 17))/sin(pi*Rational(4, 17))).rewrite(pow) + assert cot(pi/19).rewrite(pow) == cot(pi/19) + assert cot(pi/19).rewrite(sqrt) == cot(pi/19) + assert cot(pi*Rational(2, 5), evaluate=False).rewrite(sqrt) == \ + (Rational(-1, 4) + sqrt(5)/4) / sqrt(sqrt(5)/8 + Rational(5, 8)) + + +def test_cot_subs(): + assert cot(x).subs(cot(x), y) == y + assert cot(x).subs(x, y) == cot(y) + assert cot(x).subs(x, 0) is zoo + assert cot(x).subs(x, S.Pi) is zoo + + +def test_cot_expansion(): + assert cot(x + y).expand(trig=True).together() == ( + (cot(x)*cot(y) - 1)/(cot(x) + cot(y))) + assert cot(x - y).expand(trig=True).together() == ( + cot(x)*cot(-y) - 1)/(cot(x) + cot(-y)) + assert cot(x + y + z).expand(trig=True).together() == ( + (cot(x)*cot(y)*cot(z) - cot(x) - cot(y) - cot(z))/ + (-1 + cot(x)*cot(y) + cot(x)*cot(z) + cot(y)*cot(z))) + assert cot(3*x).expand(trig=True).together() == ( + (cot(x)**2 - 3)*cot(x)/(3*cot(x)**2 - 1)) + assert cot(2*x).expand(trig=True) == cot(x)/2 - 1/(2*cot(x)) + assert cot(3*x).expand(trig=True).together() == ( + cot(x)**2 - 3)*cot(x)/(3*cot(x)**2 - 1) + assert cot(4*x - pi/4).expand(trig=True).cancel() == ( + -tan(x)**4 + 4*tan(x)**3 + 6*tan(x)**2 - 4*tan(x) - 1 + )/(tan(x)**4 + 4*tan(x)**3 - 6*tan(x)**2 - 4*tan(x) + 1) + _test_extrig(cot, 2, (-1 + cot(1)**2)/(2*cot(1))) + _test_extrig(cot, 3, (-3*cot(1) + cot(1)**3)/(-1 + 3*cot(1)**2)) + + +def test_cot_AccumBounds(): + assert cot(AccumBounds(-oo, oo)) == AccumBounds(-oo, oo) + assert cot(AccumBounds(-S.Pi/3, S.Pi/3)) == AccumBounds(-oo, oo) + assert cot(AccumBounds(S.Pi/6, S.Pi/3)) == AccumBounds(cot(S.Pi/3), cot(S.Pi/6)) + + +def test_cot_fdiff(): + assert cot(x).fdiff() == -cot(x)**2 - 1 + raises(ArgumentIndexError, lambda: cot(x).fdiff(2)) + + +def test_sinc(): + assert isinstance(sinc(x), sinc) + + s = Symbol('s', zero=True) + assert sinc(s) is S.One + assert sinc(S.Infinity) is S.Zero + assert sinc(S.NegativeInfinity) is S.Zero + assert sinc(S.NaN) is S.NaN + assert sinc(S.ComplexInfinity) is S.NaN + + n = Symbol('n', integer=True, nonzero=True) + assert sinc(n*pi) is S.Zero + assert sinc(-n*pi) is S.Zero + assert sinc(pi/2) == 2 / pi + assert sinc(-pi/2) == 2 / pi + assert sinc(pi*Rational(5, 2)) == 2 / (5*pi) + assert sinc(pi*Rational(7, 2)) == -2 / (7*pi) + + assert sinc(-x) == sinc(x) + + assert sinc(x).diff(x) == cos(x)/x - sin(x)/x**2 + assert sinc(x).diff(x) == (sin(x)/x).diff(x) + assert sinc(x).diff(x, x) == (-sin(x) - 2*cos(x)/x + 2*sin(x)/x**2)/x + assert sinc(x).diff(x, x) == (sin(x)/x).diff(x, x) + assert limit(sinc(x).diff(x), x, 0) == 0 + assert limit(sinc(x).diff(x, x), x, 0) == -S(1)/3 + + # https://github.com/sympy/sympy/issues/11402 + # + # assert sinc(x).diff(x) == Piecewise(((x*cos(x) - sin(x)) / x**2, Ne(x, 0)), (0, True)) + # + # assert sinc(x).diff(x).equals(sinc(x).rewrite(sin).diff(x)) + # + # assert sinc(x).diff(x).subs(x, 0) is S.Zero + + assert sinc(x).series() == 1 - x**2/6 + x**4/120 + O(x**6) + + assert sinc(x).rewrite(jn) == jn(0, x) + assert sinc(x).rewrite(sin) == Piecewise((sin(x)/x, Ne(x, 0)), (1, True)) + assert sinc(pi, evaluate=False).is_zero is True + assert sinc(0, evaluate=False).is_zero is False + assert sinc(n*pi, evaluate=False).is_zero is True + assert sinc(x).is_zero is None + xr = Symbol('xr', real=True, nonzero=True) + assert sinc(x).is_real is None + assert sinc(xr).is_real is True + assert sinc(I*xr).is_real is True + assert sinc(I*100).is_real is True + assert sinc(x).is_finite is None + assert sinc(xr).is_finite is True + + +def test_asin(): + assert asin(nan) is nan + + assert asin.nargs == FiniteSet(1) + assert asin(oo) == -I*oo + assert asin(-oo) == I*oo + assert asin(zoo) is zoo + + # Note: asin(-x) = - asin(x) + assert asin(0) == 0 + assert asin(1) == pi/2 + assert asin(-1) == -pi/2 + assert asin(sqrt(3)/2) == pi/3 + assert asin(-sqrt(3)/2) == -pi/3 + assert asin(sqrt(2)/2) == pi/4 + assert asin(-sqrt(2)/2) == -pi/4 + assert asin(sqrt((5 - sqrt(5))/8)) == pi/5 + assert asin(-sqrt((5 - sqrt(5))/8)) == -pi/5 + assert asin(S.Half) == pi/6 + assert asin(Rational(-1, 2)) == -pi/6 + assert asin((sqrt(2 - sqrt(2)))/2) == pi/8 + assert asin(-(sqrt(2 - sqrt(2)))/2) == -pi/8 + assert asin((sqrt(5) - 1)/4) == pi/10 + assert asin(-(sqrt(5) - 1)/4) == -pi/10 + assert asin((sqrt(3) - 1)/sqrt(2**3)) == pi/12 + assert asin(-(sqrt(3) - 1)/sqrt(2**3)) == -pi/12 + + # check round-trip for exact values: + for d in [5, 6, 8, 10, 12]: + for n in range(-(d//2), d//2 + 1): + if gcd(n, d) == 1: + assert asin(sin(n*pi/d)) == n*pi/d + + assert asin(x).diff(x) == 1/sqrt(1 - x**2) + + assert asin(0.2, evaluate=False).is_real is True + assert asin(-2).is_real is False + assert asin(r).is_real is None + + assert asin(-2*I) == -I*asinh(2) + + assert asin(Rational(1, 7), evaluate=False).is_positive is True + assert asin(Rational(-1, 7), evaluate=False).is_positive is False + assert asin(p).is_positive is None + assert asin(sin(Rational(7, 2))) == Rational(-7, 2) + pi + assert asin(sin(Rational(-7, 4))) == Rational(7, 4) - pi + assert unchanged(asin, cos(x)) + + +def test_asin_series(): + assert asin(x).series(x, 0, 9) == \ + x + x**3/6 + 3*x**5/40 + 5*x**7/112 + O(x**9) + t5 = asin(x).taylor_term(5, x) + assert t5 == 3*x**5/40 + assert asin(x).taylor_term(7, x, t5, 0) == 5*x**7/112 + + +def test_asin_leading_term(): + assert asin(x).as_leading_term(x) == x + # Tests concerning branch points + assert asin(x + 1).as_leading_term(x) == pi/2 + assert asin(x - 1).as_leading_term(x) == -pi/2 + assert asin(1/x).as_leading_term(x, cdir=1) == I*log(x) + pi/2 - I*log(2) + assert asin(1/x).as_leading_term(x, cdir=-1) == -I*log(x) - 3*pi/2 + I*log(2) + # Tests concerning points lying on branch cuts + assert asin(I*x + 2).as_leading_term(x, cdir=1) == pi - asin(2) + assert asin(-I*x + 2).as_leading_term(x, cdir=1) == asin(2) + assert asin(I*x - 2).as_leading_term(x, cdir=1) == -asin(2) + assert asin(-I*x - 2).as_leading_term(x, cdir=1) == -pi + asin(2) + # Tests concerning im(ndir) == 0 + assert asin(-I*x**2 + x - 2).as_leading_term(x, cdir=1) == -pi/2 + I*log(2 - sqrt(3)) + assert asin(-I*x**2 + x - 2).as_leading_term(x, cdir=-1) == -pi/2 + I*log(2 - sqrt(3)) + + +def test_asin_rewrite(): + assert asin(x).rewrite(log) == -I*log(I*x + sqrt(1 - x**2)) + assert asin(x).rewrite(atan) == 2*atan(x/(1 + sqrt(1 - x**2))) + assert asin(x).rewrite(acos) == S.Pi/2 - acos(x) + assert asin(x).rewrite(acot) == 2*acot((sqrt(-x**2 + 1) + 1)/x) + assert asin(x).rewrite(asec) == -asec(1/x) + pi/2 + assert asin(x).rewrite(acsc) == acsc(1/x) + + +def test_asin_fdiff(): + assert asin(x).fdiff() == 1/sqrt(1 - x**2) + raises(ArgumentIndexError, lambda: asin(x).fdiff(2)) + + +def test_acos(): + assert acos(nan) is nan + assert acos(zoo) is zoo + + assert acos.nargs == FiniteSet(1) + assert acos(oo) == I*oo + assert acos(-oo) == -I*oo + + # Note: acos(-x) = pi - acos(x) + assert acos(0) == pi/2 + assert acos(S.Half) == pi/3 + assert acos(Rational(-1, 2)) == pi*Rational(2, 3) + assert acos(1) == 0 + assert acos(-1) == pi + assert acos(sqrt(2)/2) == pi/4 + assert acos(-sqrt(2)/2) == pi*Rational(3, 4) + + # check round-trip for exact values: + for d in range(5, 13): + for num in range(d): + if gcd(num, d) == 1: + assert acos(cos(num*pi/d)) == num*pi/d + assert acos(-cos(num*pi/d)) == pi - num*pi/d + assert acos(sin(num*pi/d)) == pi/2 - asin(sin(num*pi/d)) + assert acos(-sin(num*pi/d)) == pi/2 - asin(-sin(num*pi/d)) + + assert acos(2*I) == pi/2 - asin(2*I) + + assert acos(x).diff(x) == -1/sqrt(1 - x**2) + + assert acos(0.2).is_real is True + assert acos(-2).is_real is False + assert acos(r).is_real is None + + assert acos(Rational(1, 7), evaluate=False).is_positive is True + assert acos(Rational(-1, 7), evaluate=False).is_positive is True + assert acos(Rational(3, 2), evaluate=False).is_positive is False + assert acos(p).is_positive is None + + assert acos(2 + p).conjugate() != acos(10 + p) + assert acos(-3 + n).conjugate() != acos(-3 + n) + assert acos(Rational(1, 3)).conjugate() == acos(Rational(1, 3)) + assert acos(Rational(-1, 3)).conjugate() == acos(Rational(-1, 3)) + assert acos(p + n*I).conjugate() == acos(p - n*I) + assert acos(z).conjugate() != acos(conjugate(z)) + + +def test_acos_leading_term(): + assert acos(x).as_leading_term(x) == pi/2 + # Tests concerning branch points + assert acos(x + 1).as_leading_term(x) == sqrt(2)*sqrt(-x) + assert acos(x - 1).as_leading_term(x) == pi + assert acos(1/x).as_leading_term(x, cdir=1) == -I*log(x) + I*log(2) + assert acos(1/x).as_leading_term(x, cdir=-1) == I*log(x) + 2*pi - I*log(2) + # Tests concerning points lying on branch cuts + assert acos(I*x + 2).as_leading_term(x, cdir=1) == -acos(2) + assert acos(-I*x + 2).as_leading_term(x, cdir=1) == acos(2) + assert acos(I*x - 2).as_leading_term(x, cdir=1) == acos(-2) + assert acos(-I*x - 2).as_leading_term(x, cdir=1) == 2*pi - acos(-2) + # Tests concerning im(ndir) == 0 + assert acos(-I*x**2 + x - 2).as_leading_term(x, cdir=1) == pi + I*log(sqrt(3) + 2) + assert acos(-I*x**2 + x - 2).as_leading_term(x, cdir=-1) == pi + I*log(sqrt(3) + 2) + + +def test_acos_series(): + assert acos(x).series(x, 0, 8) == \ + pi/2 - x - x**3/6 - 3*x**5/40 - 5*x**7/112 + O(x**8) + assert acos(x).series(x, 0, 8) == pi/2 - asin(x).series(x, 0, 8) + t5 = acos(x).taylor_term(5, x) + assert t5 == -3*x**5/40 + assert acos(x).taylor_term(7, x, t5, 0) == -5*x**7/112 + assert acos(x).taylor_term(0, x) == pi/2 + assert acos(x).taylor_term(2, x) is S.Zero + + +def test_acos_rewrite(): + assert acos(x).rewrite(log) == pi/2 + I*log(I*x + sqrt(1 - x**2)) + assert acos(x).rewrite(atan) == pi*(-x*sqrt(x**(-2)) + 1)/2 + atan(sqrt(1 - x**2)/x) + assert acos(0).rewrite(atan) == S.Pi/2 + assert acos(0.5).rewrite(atan) == acos(0.5).rewrite(log) + assert acos(x).rewrite(asin) == S.Pi/2 - asin(x) + assert acos(x).rewrite(acot) == -2*acot((sqrt(-x**2 + 1) + 1)/x) + pi/2 + assert acos(x).rewrite(asec) == asec(1/x) + assert acos(x).rewrite(acsc) == -acsc(1/x) + pi/2 + + +def test_acos_fdiff(): + assert acos(x).fdiff() == -1/sqrt(1 - x**2) + raises(ArgumentIndexError, lambda: acos(x).fdiff(2)) + + +def test_atan(): + assert atan(nan) is nan + + assert atan.nargs == FiniteSet(1) + assert atan(oo) == pi/2 + assert atan(-oo) == -pi/2 + assert atan(zoo) == AccumBounds(-pi/2, pi/2) + + assert atan(0) == 0 + assert atan(1) == pi/4 + assert atan(sqrt(3)) == pi/3 + assert atan(-(1 + sqrt(2))) == pi*Rational(-3, 8) + assert atan(sqrt(5 - 2 * sqrt(5))) == pi/5 + assert atan(-sqrt(1 - 2 * sqrt(5)/ 5)) == -pi/10 + assert atan(sqrt(1 + 2 * sqrt(5) / 5)) == pi*Rational(3, 10) + assert atan(-2 + sqrt(3)) == -pi/12 + assert atan(2 + sqrt(3)) == pi*Rational(5, 12) + assert atan(-2 - sqrt(3)) == pi*Rational(-5, 12) + + # check round-trip for exact values: + for d in [5, 6, 8, 10, 12]: + for num in range(-(d//2), d//2 + 1): + if gcd(num, d) == 1: + assert atan(tan(num*pi/d)) == num*pi/d + + assert atan(oo) == pi/2 + assert atan(x).diff(x) == 1/(1 + x**2) + + assert atan(r).is_real is True + + assert atan(-2*I) == -I*atanh(2) + assert unchanged(atan, cot(x)) + assert atan(cot(Rational(1, 4))) == Rational(-1, 4) + pi/2 + assert acot(Rational(1, 4)).is_rational is False + + for s in (x, p, n, np, nn, nz, ep, en, enp, enn, enz): + if s.is_real or s.is_extended_real is None: + assert s.is_nonzero is atan(s).is_nonzero + assert s.is_positive is atan(s).is_positive + assert s.is_negative is atan(s).is_negative + assert s.is_nonpositive is atan(s).is_nonpositive + assert s.is_nonnegative is atan(s).is_nonnegative + else: + assert s.is_extended_nonzero is atan(s).is_nonzero + assert s.is_extended_positive is atan(s).is_positive + assert s.is_extended_negative is atan(s).is_negative + assert s.is_extended_nonpositive is atan(s).is_nonpositive + assert s.is_extended_nonnegative is atan(s).is_nonnegative + assert s.is_extended_nonzero is atan(s).is_extended_nonzero + assert s.is_extended_positive is atan(s).is_extended_positive + assert s.is_extended_negative is atan(s).is_extended_negative + assert s.is_extended_nonpositive is atan(s).is_extended_nonpositive + assert s.is_extended_nonnegative is atan(s).is_extended_nonnegative + + +def test_atan_rewrite(): + assert atan(x).rewrite(log) == I*(log(1 - I*x)-log(1 + I*x))/2 + assert atan(x).rewrite(asin) == (-asin(1/sqrt(x**2 + 1)) + pi/2)*sqrt(x**2)/x + assert atan(x).rewrite(acos) == sqrt(x**2)*acos(1/sqrt(x**2 + 1))/x + assert atan(x).rewrite(acot) == acot(1/x) + assert atan(x).rewrite(asec) == sqrt(x**2)*asec(sqrt(x**2 + 1))/x + assert atan(x).rewrite(acsc) == (-acsc(sqrt(x**2 + 1)) + pi/2)*sqrt(x**2)/x + + assert atan(-5*I).evalf() == atan(x).rewrite(log).evalf(subs={x:-5*I}) + assert atan(5*I).evalf() == atan(x).rewrite(log).evalf(subs={x:5*I}) + + +def test_atan_fdiff(): + assert atan(x).fdiff() == 1/(x**2 + 1) + raises(ArgumentIndexError, lambda: atan(x).fdiff(2)) + + +def test_atan_leading_term(): + assert atan(x).as_leading_term(x) == x + assert atan(1/x).as_leading_term(x, cdir=1) == pi/2 + assert atan(1/x).as_leading_term(x, cdir=-1) == -pi/2 + # Tests concerning branch points + assert atan(x + I).as_leading_term(x, cdir=1) == -I*log(x)/2 + pi/4 + I*log(2)/2 + assert atan(x + I).as_leading_term(x, cdir=-1) == -I*log(x)/2 - 3*pi/4 + I*log(2)/2 + assert atan(x - I).as_leading_term(x, cdir=1) == I*log(x)/2 + pi/4 - I*log(2)/2 + assert atan(x - I).as_leading_term(x, cdir=-1) == I*log(x)/2 + pi/4 - I*log(2)/2 + # Tests concerning points lying on branch cuts + assert atan(x + 2*I).as_leading_term(x, cdir=1) == I*atanh(2) + assert atan(x + 2*I).as_leading_term(x, cdir=-1) == -pi + I*atanh(2) + assert atan(x - 2*I).as_leading_term(x, cdir=1) == pi - I*atanh(2) + assert atan(x - 2*I).as_leading_term(x, cdir=-1) == -I*atanh(2) + # Tests concerning re(ndir) == 0 + assert atan(2*I - I*x - x**2).as_leading_term(x, cdir=1) == -pi/2 + I*log(3)/2 + assert atan(2*I - I*x - x**2).as_leading_term(x, cdir=-1) == -pi/2 + I*log(3)/2 + + +def test_atan2(): + assert atan2.nargs == FiniteSet(2) + assert atan2(0, 0) is S.NaN + assert atan2(0, 1) == 0 + assert atan2(1, 1) == pi/4 + assert atan2(1, 0) == pi/2 + assert atan2(1, -1) == pi*Rational(3, 4) + assert atan2(0, -1) == pi + assert atan2(-1, -1) == pi*Rational(-3, 4) + assert atan2(-1, 0) == -pi/2 + assert atan2(-1, 1) == -pi/4 + i = symbols('i', imaginary=True) + r = symbols('r', real=True) + eq = atan2(r, i) + ans = -I*log((i + I*r)/sqrt(i**2 + r**2)) + reps = ((r, 2), (i, I)) + assert eq.subs(reps) == ans.subs(reps) + + x = Symbol('x', negative=True) + y = Symbol('y', negative=True) + assert atan2(y, x) == atan(y/x) - pi + y = Symbol('y', nonnegative=True) + assert atan2(y, x) == atan(y/x) + pi + y = Symbol('y') + assert atan2(y, x) == atan2(y, x, evaluate=False) + + u = Symbol("u", positive=True) + assert atan2(0, u) == 0 + u = Symbol("u", negative=True) + assert atan2(0, u) == pi + + assert atan2(y, oo) == 0 + assert atan2(y, -oo)== 2*pi*Heaviside(re(y), S.Half) - pi + + assert atan2(y, x).rewrite(log) == -I*log((x + I*y)/sqrt(x**2 + y**2)) + assert atan2(0, 0) is S.NaN + + ex = atan2(y, x) - arg(x + I*y) + assert ex.subs({x:2, y:3}).rewrite(arg) == 0 + assert ex.subs({x:2, y:3*I}).rewrite(arg) == -pi - I*log(sqrt(5)*I/5) + assert ex.subs({x:2*I, y:3}).rewrite(arg) == -pi/2 - I*log(sqrt(5)*I) + assert ex.subs({x:2*I, y:3*I}).rewrite(arg) == -pi + atan(Rational(2, 3)) + atan(Rational(3, 2)) + i = symbols('i', imaginary=True) + r = symbols('r', real=True) + e = atan2(i, r) + rewrite = e.rewrite(arg) + reps = {i: I, r: -2} + assert rewrite == -I*log(abs(I*i + r)/sqrt(abs(i**2 + r**2))) + arg((I*i + r)/sqrt(i**2 + r**2)) + assert (e - rewrite).subs(reps).equals(0) + + assert atan2(0, x).rewrite(atan) == Piecewise((pi, re(x) < 0), + (0, Ne(x, 0)), + (nan, True)) + assert atan2(0, r).rewrite(atan) == Piecewise((pi, r < 0), (0, Ne(r, 0)), (S.NaN, True)) + assert atan2(0, i),rewrite(atan) == 0 + assert atan2(0, r + i).rewrite(atan) == Piecewise((pi, r < 0), (0, True)) + + assert atan2(y, x).rewrite(atan) == Piecewise( + (2*atan(y/(x + sqrt(x**2 + y**2))), Ne(y, 0)), + (pi, re(x) < 0), + (0, (re(x) > 0) | Ne(im(x), 0)), + (nan, True)) + assert conjugate(atan2(x, y)) == atan2(conjugate(x), conjugate(y)) + + assert diff(atan2(y, x), x) == -y/(x**2 + y**2) + assert diff(atan2(y, x), y) == x/(x**2 + y**2) + + assert simplify(diff(atan2(y, x).rewrite(log), x)) == -y/(x**2 + y**2) + assert simplify(diff(atan2(y, x).rewrite(log), y)) == x/(x**2 + y**2) + + assert str(atan2(1, 2).evalf(5)) == '0.46365' + raises(ArgumentIndexError, lambda: atan2(x, y).fdiff(3)) + +def test_issue_17461(): + class A(Symbol): + is_extended_real = True + + def _eval_evalf(self, prec): + return Float(5.0) + + x = A('X') + y = A('Y') + assert abs(atan2(x, y).evalf() - 0.785398163397448) <= 1e-10 + +def test_acot(): + assert acot(nan) is nan + + assert acot.nargs == FiniteSet(1) + assert acot(-oo) == 0 + assert acot(oo) == 0 + assert acot(zoo) == 0 + assert acot(1) == pi/4 + assert acot(0) == pi/2 + assert acot(sqrt(3)/3) == pi/3 + assert acot(1/sqrt(3)) == pi/3 + assert acot(-1/sqrt(3)) == -pi/3 + assert acot(x).diff(x) == -1/(1 + x**2) + + assert acot(r).is_extended_real is True + + assert acot(I*pi) == -I*acoth(pi) + assert acot(-2*I) == I*acoth(2) + assert acot(x).is_positive is None + assert acot(n).is_positive is False + assert acot(p).is_positive is True + assert acot(I).is_positive is False + assert acot(Rational(1, 4)).is_rational is False + assert unchanged(acot, cot(x)) + assert unchanged(acot, tan(x)) + assert acot(cot(Rational(1, 4))) == Rational(1, 4) + assert acot(tan(Rational(-1, 4))) == Rational(1, 4) - pi/2 + + +def test_acot_rewrite(): + assert acot(x).rewrite(log) == I*(log(1 - I/x)-log(1 + I/x))/2 + assert acot(x).rewrite(asin) == x*(-asin(sqrt(-x**2)/sqrt(-x**2 - 1)) + pi/2)*sqrt(x**(-2)) + assert acot(x).rewrite(acos) == x*sqrt(x**(-2))*acos(sqrt(-x**2)/sqrt(-x**2 - 1)) + assert acot(x).rewrite(atan) == atan(1/x) + assert acot(x).rewrite(asec) == x*sqrt(x**(-2))*asec(sqrt((x**2 + 1)/x**2)) + assert acot(x).rewrite(acsc) == x*(-acsc(sqrt((x**2 + 1)/x**2)) + pi/2)*sqrt(x**(-2)) + + assert acot(-I/5).evalf() == acot(x).rewrite(log).evalf(subs={x:-I/5}) + assert acot(I/5).evalf() == acot(x).rewrite(log).evalf(subs={x:I/5}) + + +def test_acot_fdiff(): + assert acot(x).fdiff() == -1/(x**2 + 1) + raises(ArgumentIndexError, lambda: acot(x).fdiff(2)) + +def test_acot_leading_term(): + assert acot(1/x).as_leading_term(x) == x + # Tests concerning branch points + assert acot(x + I).as_leading_term(x, cdir=1) == I*log(x)/2 + pi/4 - I*log(2)/2 + assert acot(x + I).as_leading_term(x, cdir=-1) == I*log(x)/2 + pi/4 - I*log(2)/2 + assert acot(x - I).as_leading_term(x, cdir=1) == -I*log(x)/2 + pi/4 + I*log(2)/2 + assert acot(x - I).as_leading_term(x, cdir=-1) == -I*log(x)/2 - 3*pi/4 + I*log(2)/2 + # Tests concerning points lying on branch cuts + assert acot(x).as_leading_term(x, cdir=1) == pi/2 + assert acot(x).as_leading_term(x, cdir=-1) == -pi/2 + assert acot(x + I/2).as_leading_term(x, cdir=1) == pi - I*acoth(S(1)/2) + assert acot(x + I/2).as_leading_term(x, cdir=-1) == -I*acoth(S(1)/2) + assert acot(x - I/2).as_leading_term(x, cdir=1) == I*acoth(S(1)/2) + assert acot(x - I/2).as_leading_term(x, cdir=-1) == -pi + I*acoth(S(1)/2) + # Tests concerning re(ndir) == 0 + assert acot(I/2 - I*x - x**2).as_leading_term(x, cdir=1) == -pi/2 - I*log(3)/2 + assert acot(I/2 - I*x - x**2).as_leading_term(x, cdir=-1) == -pi/2 - I*log(3)/2 + + +def test_attributes(): + assert sin(x).args == (x,) + + +def test_sincos_rewrite(): + assert sin(pi/2 - x) == cos(x) + assert sin(pi - x) == sin(x) + assert cos(pi/2 - x) == sin(x) + assert cos(pi - x) == -cos(x) + + +def _check_even_rewrite(func, arg): + """Checks that the expr has been rewritten using f(-x) -> f(x) + arg : -x + """ + return func(arg).args[0] == -arg + + +def _check_odd_rewrite(func, arg): + """Checks that the expr has been rewritten using f(-x) -> -f(x) + arg : -x + """ + return func(arg).func.is_Mul + + +def _check_no_rewrite(func, arg): + """Checks that the expr is not rewritten""" + return func(arg).args[0] == arg + + +def test_evenodd_rewrite(): + a = cos(2) # negative + b = sin(1) # positive + even = [cos] + odd = [sin, tan, cot, asin, atan, acot] + with_minus = [-1, -2**1024 * E, -pi/105, -x*y, -x - y] + for func in even: + for expr in with_minus: + assert _check_even_rewrite(func, expr) + assert _check_no_rewrite(func, a*b) + assert func( + x - y) == func(y - x) # it doesn't matter which form is canonical + for func in odd: + for expr in with_minus: + assert _check_odd_rewrite(func, expr) + assert _check_no_rewrite(func, a*b) + assert func( + x - y) == -func(y - x) # it doesn't matter which form is canonical + + +def test_as_leading_term_issue_5272(): + assert sin(x).as_leading_term(x) == x + assert cos(x).as_leading_term(x) == 1 + assert tan(x).as_leading_term(x) == x + assert cot(x).as_leading_term(x) == 1/x + + +def test_leading_terms(): + assert sin(1/x).as_leading_term(x) == AccumBounds(-1, 1) + assert sin(S.Half).as_leading_term(x) == sin(S.Half) + assert cos(1/x).as_leading_term(x) == AccumBounds(-1, 1) + assert cos(S.Half).as_leading_term(x) == cos(S.Half) + assert sec(1/x).as_leading_term(x) == AccumBounds(S.NegativeInfinity, S.Infinity) + assert csc(1/x).as_leading_term(x) == AccumBounds(S.NegativeInfinity, S.Infinity) + assert tan(1/x).as_leading_term(x) == AccumBounds(S.NegativeInfinity, S.Infinity) + assert cot(1/x).as_leading_term(x) == AccumBounds(S.NegativeInfinity, S.Infinity) + + # https://github.com/sympy/sympy/issues/21038 + f = sin(pi*(x + 4))/(3*x) + assert f.as_leading_term(x) == pi/3 + + +def test_atan2_expansion(): + assert cancel(atan2(x**2, x + 1).diff(x) - atan(x**2/(x + 1)).diff(x)) == 0 + assert cancel(atan(y/x).series(y, 0, 5) - atan2(y, x).series(y, 0, 5) + + atan2(0, x) - atan(0)) == O(y**5) + assert cancel(atan(y/x).series(x, 1, 4) - atan2(y, x).series(x, 1, 4) + + atan2(y, 1) - atan(y)) == O((x - 1)**4, (x, 1)) + assert cancel(atan((y + x)/x).series(x, 1, 3) - atan2(y + x, x).series(x, 1, 3) + + atan2(1 + y, 1) - atan(1 + y)) == O((x - 1)**3, (x, 1)) + assert Matrix([atan2(y, x)]).jacobian([y, x]) == \ + Matrix([[x/(y**2 + x**2), -y/(y**2 + x**2)]]) + + +def test_aseries(): + def t(n, v, d, e): + assert abs( + n(1/v).evalf() - n(1/x).series(x, dir=d).removeO().subs(x, v)) < e + t(atan, 0.1, '+', 1e-5) + t(atan, -0.1, '-', 1e-5) + t(acot, 0.1, '+', 1e-5) + t(acot, -0.1, '-', 1e-5) + + +def test_issue_4420(): + i = Symbol('i', integer=True) + e = Symbol('e', even=True) + o = Symbol('o', odd=True) + + # unknown parity for variable + assert cos(4*i*pi) == 1 + assert sin(4*i*pi) == 0 + assert tan(4*i*pi) == 0 + assert cot(4*i*pi) is zoo + + assert cos(3*i*pi) == cos(pi*i) # +/-1 + assert sin(3*i*pi) == 0 + assert tan(3*i*pi) == 0 + assert cot(3*i*pi) is zoo + + assert cos(4.0*i*pi) == 1 + assert sin(4.0*i*pi) == 0 + assert tan(4.0*i*pi) == 0 + assert cot(4.0*i*pi) is zoo + + assert cos(3.0*i*pi) == cos(pi*i) # +/-1 + assert sin(3.0*i*pi) == 0 + assert tan(3.0*i*pi) == 0 + assert cot(3.0*i*pi) is zoo + + assert cos(4.5*i*pi) == cos(0.5*pi*i) + assert sin(4.5*i*pi) == sin(0.5*pi*i) + assert tan(4.5*i*pi) == tan(0.5*pi*i) + assert cot(4.5*i*pi) == cot(0.5*pi*i) + + # parity of variable is known + assert cos(4*e*pi) == 1 + assert sin(4*e*pi) == 0 + assert tan(4*e*pi) == 0 + assert cot(4*e*pi) is zoo + + assert cos(3*e*pi) == 1 + assert sin(3*e*pi) == 0 + assert tan(3*e*pi) == 0 + assert cot(3*e*pi) is zoo + + assert cos(4.0*e*pi) == 1 + assert sin(4.0*e*pi) == 0 + assert tan(4.0*e*pi) == 0 + assert cot(4.0*e*pi) is zoo + + assert cos(3.0*e*pi) == 1 + assert sin(3.0*e*pi) == 0 + assert tan(3.0*e*pi) == 0 + assert cot(3.0*e*pi) is zoo + + assert cos(4.5*e*pi) == cos(0.5*pi*e) + assert sin(4.5*e*pi) == sin(0.5*pi*e) + assert tan(4.5*e*pi) == tan(0.5*pi*e) + assert cot(4.5*e*pi) == cot(0.5*pi*e) + + assert cos(4*o*pi) == 1 + assert sin(4*o*pi) == 0 + assert tan(4*o*pi) == 0 + assert cot(4*o*pi) is zoo + + assert cos(3*o*pi) == -1 + assert sin(3*o*pi) == 0 + assert tan(3*o*pi) == 0 + assert cot(3*o*pi) is zoo + + assert cos(4.0*o*pi) == 1 + assert sin(4.0*o*pi) == 0 + assert tan(4.0*o*pi) == 0 + assert cot(4.0*o*pi) is zoo + + assert cos(3.0*o*pi) == -1 + assert sin(3.0*o*pi) == 0 + assert tan(3.0*o*pi) == 0 + assert cot(3.0*o*pi) is zoo + + assert cos(4.5*o*pi) == cos(0.5*pi*o) + assert sin(4.5*o*pi) == sin(0.5*pi*o) + assert tan(4.5*o*pi) == tan(0.5*pi*o) + assert cot(4.5*o*pi) == cot(0.5*pi*o) + + # x could be imaginary + assert cos(4*x*pi) == cos(4*pi*x) + assert sin(4*x*pi) == sin(4*pi*x) + assert tan(4*x*pi) == tan(4*pi*x) + assert cot(4*x*pi) == cot(4*pi*x) + + assert cos(3*x*pi) == cos(3*pi*x) + assert sin(3*x*pi) == sin(3*pi*x) + assert tan(3*x*pi) == tan(3*pi*x) + assert cot(3*x*pi) == cot(3*pi*x) + + assert cos(4.0*x*pi) == cos(4.0*pi*x) + assert sin(4.0*x*pi) == sin(4.0*pi*x) + assert tan(4.0*x*pi) == tan(4.0*pi*x) + assert cot(4.0*x*pi) == cot(4.0*pi*x) + + assert cos(3.0*x*pi) == cos(3.0*pi*x) + assert sin(3.0*x*pi) == sin(3.0*pi*x) + assert tan(3.0*x*pi) == tan(3.0*pi*x) + assert cot(3.0*x*pi) == cot(3.0*pi*x) + + assert cos(4.5*x*pi) == cos(4.5*pi*x) + assert sin(4.5*x*pi) == sin(4.5*pi*x) + assert tan(4.5*x*pi) == tan(4.5*pi*x) + assert cot(4.5*x*pi) == cot(4.5*pi*x) + + +def test_inverses(): + raises(AttributeError, lambda: sin(x).inverse()) + raises(AttributeError, lambda: cos(x).inverse()) + assert tan(x).inverse() == atan + assert cot(x).inverse() == acot + raises(AttributeError, lambda: csc(x).inverse()) + raises(AttributeError, lambda: sec(x).inverse()) + assert asin(x).inverse() == sin + assert acos(x).inverse() == cos + assert atan(x).inverse() == tan + assert acot(x).inverse() == cot + + +def test_real_imag(): + a, b = symbols('a b', real=True) + z = a + b*I + for deep in [True, False]: + assert sin( + z).as_real_imag(deep=deep) == (sin(a)*cosh(b), cos(a)*sinh(b)) + assert cos( + z).as_real_imag(deep=deep) == (cos(a)*cosh(b), -sin(a)*sinh(b)) + assert tan(z).as_real_imag(deep=deep) == (sin(2*a)/(cos(2*a) + + cosh(2*b)), sinh(2*b)/(cos(2*a) + cosh(2*b))) + assert cot(z).as_real_imag(deep=deep) == (-sin(2*a)/(cos(2*a) - + cosh(2*b)), sinh(2*b)/(cos(2*a) - cosh(2*b))) + assert sin(a).as_real_imag(deep=deep) == (sin(a), 0) + assert cos(a).as_real_imag(deep=deep) == (cos(a), 0) + assert tan(a).as_real_imag(deep=deep) == (tan(a), 0) + assert cot(a).as_real_imag(deep=deep) == (cot(a), 0) + + +@slow +def test_sincos_rewrite_sqrt(): + # equivalent to testing rewrite(pow) + for p in [1, 3, 5, 17]: + for t in [1, 8]: + n = t*p + # The vertices `exp(i*pi/n)` of a regular `n`-gon can + # be expressed by means of nested square roots if and + # only if `n` is a product of Fermat primes, `p`, and + # powers of 2, `t'. The code aims to check all vertices + # not belonging to an `m`-gon for `m < n`(`gcd(i, n) == 1`). + # For large `n` this makes the test too slow, therefore + # the vertices are limited to those of index `i < 10`. + for i in range(1, min((n + 1)//2 + 1, 10)): + if 1 == gcd(i, n): + x = i*pi/n + s1 = sin(x).rewrite(sqrt) + c1 = cos(x).rewrite(sqrt) + assert not s1.has(cos, sin), "fails for %d*pi/%d" % (i, n) + assert not c1.has(cos, sin), "fails for %d*pi/%d" % (i, n) + assert 1e-3 > abs(sin(x.evalf(5)) - s1.evalf(2)), "fails for %d*pi/%d" % (i, n) + assert 1e-3 > abs(cos(x.evalf(5)) - c1.evalf(2)), "fails for %d*pi/%d" % (i, n) + assert cos(pi/14).rewrite(sqrt) == sqrt(cos(pi/7)/2 + S.Half) + assert cos(pi*Rational(-15, 2)/11, evaluate=False).rewrite( + sqrt) == -sqrt(-cos(pi*Rational(4, 11))/2 + S.Half) + assert cos(Mul(2, pi, S.Half, evaluate=False), evaluate=False).rewrite( + sqrt) == -1 + e = cos(pi/3/17) # don't use pi/15 since that is caught at instantiation + a = ( + -3*sqrt(-sqrt(17) + 17)*sqrt(sqrt(17) + 17)/64 - + 3*sqrt(34)*sqrt(sqrt(17) + 17)/128 - sqrt(sqrt(17) + + 17)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + 17) + + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/64 - sqrt(-sqrt(17) + + 17)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/128 - Rational(1, 32) + + sqrt(2)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/64 + + 3*sqrt(2)*sqrt(sqrt(17) + 17)/128 + sqrt(34)*sqrt(-sqrt(17) + 17)/128 + + 13*sqrt(2)*sqrt(-sqrt(17) + 17)/128 + sqrt(17)*sqrt(-sqrt(17) + + 17)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + 17) + + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/128 + 5*sqrt(17)/32 + + sqrt(3)*sqrt(-sqrt(2)*sqrt(sqrt(17) + 17)*sqrt(sqrt(17)/32 + + sqrt(2)*sqrt(-sqrt(17) + 17)/32 + + sqrt(2)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/32 + Rational(15, 32))/8 - + 5*sqrt(2)*sqrt(sqrt(17)/32 + sqrt(2)*sqrt(-sqrt(17) + 17)/32 + + sqrt(2)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/32 + + Rational(15, 32))*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/64 - + 3*sqrt(2)*sqrt(-sqrt(17) + 17)*sqrt(sqrt(17)/32 + + sqrt(2)*sqrt(-sqrt(17) + 17)/32 + + sqrt(2)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/32 + Rational(15, 32))/32 + + sqrt(34)*sqrt(sqrt(17)/32 + sqrt(2)*sqrt(-sqrt(17) + 17)/32 + + sqrt(2)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/32 + + Rational(15, 32))*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/64 + + sqrt(sqrt(17)/32 + sqrt(2)*sqrt(-sqrt(17) + 17)/32 + + sqrt(2)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/32 + Rational(15, 32))/2 + + S.Half + sqrt(-sqrt(17) + 17)*sqrt(sqrt(17)/32 + sqrt(2)*sqrt(-sqrt(17) + + 17)/32 + sqrt(2)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - + sqrt(2)*sqrt(-sqrt(17) + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + + 6*sqrt(17) + 34)/32 + Rational(15, 32))*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - + sqrt(2)*sqrt(-sqrt(17) + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + + 6*sqrt(17) + 34)/32 + sqrt(34)*sqrt(-sqrt(17) + 17)*sqrt(sqrt(17)/32 + + sqrt(2)*sqrt(-sqrt(17) + 17)/32 + + sqrt(2)*sqrt(-8*sqrt(2)*sqrt(sqrt(17) + 17) - sqrt(2)*sqrt(-sqrt(17) + + 17) + sqrt(34)*sqrt(-sqrt(17) + 17) + 6*sqrt(17) + 34)/32 + + Rational(15, 32))/32)/2) + assert e.rewrite(sqrt) == a + assert e.n() == a.n() + # coverage of fermatCoords: multiplicity > 1; the following could be + # different but that portion of the code should be tested in some way + assert cos(pi/9/17).rewrite(sqrt) == \ + sin(pi/9)*sin(pi*Rational(2, 17)) + cos(pi/9)*cos(pi*Rational(2, 17)) + + +@slow +def test_sincos_rewrite_sqrt_257(): + assert cos(pi/257).rewrite(sqrt).evalf(64) == cos(pi/257).evalf(64) + + +@slow +def test_tancot_rewrite_sqrt(): + # equivalent to testing rewrite(pow) + for p in [1, 3, 5, 17]: + for t in [1, 8]: + n = t*p + for i in range(1, min((n + 1)//2 + 1, 10)): + if 1 == gcd(i, n): + x = i*pi/n + if 2*i != n and 3*i != 2*n: + t1 = tan(x).rewrite(sqrt) + assert not t1.has(cot, tan), "fails for %d*pi/%d" % (i, n) + assert 1e-3 > abs( tan(x.evalf(7)) - t1.evalf(4) ), "fails for %d*pi/%d" % (i, n) + if i != 0 and i != n: + c1 = cot(x).rewrite(sqrt) + assert not c1.has(cot, tan), "fails for %d*pi/%d" % (i, n) + assert 1e-3 > abs( cot(x.evalf(7)) - c1.evalf(4) ), "fails for %d*pi/%d" % (i, n) + + +def test_sec(): + x = symbols('x', real=True) + z = symbols('z') + + assert sec.nargs == FiniteSet(1) + + assert sec(zoo) is nan + assert sec(0) == 1 + assert sec(pi) == -1 + assert sec(pi/2) is zoo + assert sec(-pi/2) is zoo + assert sec(pi/6) == 2*sqrt(3)/3 + assert sec(pi/3) == 2 + assert sec(pi*Rational(5, 2)) is zoo + assert sec(pi*Rational(9, 7)) == -sec(pi*Rational(2, 7)) + assert sec(pi*Rational(3, 4)) == -sqrt(2) # issue 8421 + assert sec(I) == 1/cosh(1) + assert sec(x*I) == 1/cosh(x) + assert sec(-x) == sec(x) + + assert sec(asec(x)) == x + + assert sec(z).conjugate() == sec(conjugate(z)) + + assert (sec(z).as_real_imag() == + (cos(re(z))*cosh(im(z))/(sin(re(z))**2*sinh(im(z))**2 + + cos(re(z))**2*cosh(im(z))**2), + sin(re(z))*sinh(im(z))/(sin(re(z))**2*sinh(im(z))**2 + + cos(re(z))**2*cosh(im(z))**2))) + + assert sec(x).expand(trig=True) == 1/cos(x) + assert sec(2*x).expand(trig=True) == 1/(2*cos(x)**2 - 1) + + assert sec(x).is_extended_real == True + assert sec(z).is_real == None + + assert sec(a).is_algebraic is None + assert sec(na).is_algebraic is False + + assert sec(x).as_leading_term() == sec(x) + + assert sec(0, evaluate=False).is_finite == True + assert sec(x).is_finite == None + assert sec(pi/2, evaluate=False).is_finite == False + + assert series(sec(x), x, x0=0, n=6) == 1 + x**2/2 + 5*x**4/24 + O(x**6) + + # https://github.com/sympy/sympy/issues/7166 + assert series(sqrt(sec(x))) == 1 + x**2/4 + 7*x**4/96 + O(x**6) + + # https://github.com/sympy/sympy/issues/7167 + assert (series(sqrt(sec(x)), x, x0=pi*3/2, n=4) == + 1/sqrt(x - pi*Rational(3, 2)) + (x - pi*Rational(3, 2))**Rational(3, 2)/12 + + (x - pi*Rational(3, 2))**Rational(7, 2)/160 + O((x - pi*Rational(3, 2))**4, (x, pi*Rational(3, 2)))) + + assert sec(x).diff(x) == tan(x)*sec(x) + + # Taylor Term checks + assert sec(z).taylor_term(4, z) == 5*z**4/24 + assert sec(z).taylor_term(6, z) == 61*z**6/720 + assert sec(z).taylor_term(5, z) == 0 + + +def test_sec_rewrite(): + assert sec(x).rewrite(exp) == 1/(exp(I*x)/2 + exp(-I*x)/2) + assert sec(x).rewrite(cos) == 1/cos(x) + assert sec(x).rewrite(tan) == (tan(x/2)**2 + 1)/(-tan(x/2)**2 + 1) + assert sec(x).rewrite(pow) == sec(x) + assert sec(x).rewrite(sqrt) == sec(x) + assert sec(z).rewrite(cot) == (cot(z/2)**2 + 1)/(cot(z/2)**2 - 1) + assert sec(x).rewrite(sin) == 1 / sin(x + pi / 2, evaluate=False) + assert sec(x).rewrite(tan) == (tan(x / 2)**2 + 1) / (-tan(x / 2)**2 + 1) + assert sec(x).rewrite(csc) == csc(-x + pi/2, evaluate=False) + assert sec(x).rewrite(besselj) == Piecewise( + (sqrt(2)/(sqrt(pi*x)*besselj(-S.Half, x)), Ne(x, 0)), + (1, True) + ) + assert sec(x).rewrite(besselj).subs(x, 0) == sec(0) + + +def test_sec_fdiff(): + assert sec(x).fdiff() == tan(x)*sec(x) + raises(ArgumentIndexError, lambda: sec(x).fdiff(2)) + + +def test_csc(): + x = symbols('x', real=True) + z = symbols('z') + + # https://github.com/sympy/sympy/issues/6707 + cosecant = csc('x') + alternate = 1/sin('x') + assert cosecant.equals(alternate) == True + assert alternate.equals(cosecant) == True + + assert csc.nargs == FiniteSet(1) + + assert csc(0) is zoo + assert csc(pi) is zoo + assert csc(zoo) is nan + + assert csc(pi/2) == 1 + assert csc(-pi/2) == -1 + assert csc(pi/6) == 2 + assert csc(pi/3) == 2*sqrt(3)/3 + assert csc(pi*Rational(5, 2)) == 1 + assert csc(pi*Rational(9, 7)) == -csc(pi*Rational(2, 7)) + assert csc(pi*Rational(3, 4)) == sqrt(2) # issue 8421 + assert csc(I) == -I/sinh(1) + assert csc(x*I) == -I/sinh(x) + assert csc(-x) == -csc(x) + + assert csc(acsc(x)) == x + + assert csc(z).conjugate() == csc(conjugate(z)) + + assert (csc(z).as_real_imag() == + (sin(re(z))*cosh(im(z))/(sin(re(z))**2*cosh(im(z))**2 + + cos(re(z))**2*sinh(im(z))**2), + -cos(re(z))*sinh(im(z))/(sin(re(z))**2*cosh(im(z))**2 + + cos(re(z))**2*sinh(im(z))**2))) + + assert csc(x).expand(trig=True) == 1/sin(x) + assert csc(2*x).expand(trig=True) == 1/(2*sin(x)*cos(x)) + + assert csc(x).is_extended_real == True + assert csc(z).is_real == None + + assert csc(a).is_algebraic is None + assert csc(na).is_algebraic is False + + assert csc(x).as_leading_term() == csc(x) + + assert csc(0, evaluate=False).is_finite == False + assert csc(x).is_finite == None + assert csc(pi/2, evaluate=False).is_finite == True + + assert series(csc(x), x, x0=pi/2, n=6) == \ + 1 + (x - pi/2)**2/2 + 5*(x - pi/2)**4/24 + O((x - pi/2)**6, (x, pi/2)) + assert series(csc(x), x, x0=0, n=6) == \ + 1/x + x/6 + 7*x**3/360 + 31*x**5/15120 + O(x**6) + + assert csc(x).diff(x) == -cot(x)*csc(x) + + assert csc(x).taylor_term(2, x) == 0 + assert csc(x).taylor_term(3, x) == 7*x**3/360 + assert csc(x).taylor_term(5, x) == 31*x**5/15120 + raises(ArgumentIndexError, lambda: csc(x).fdiff(2)) + + +def test_asec(): + z = Symbol('z', zero=True) + assert asec(z) is zoo + assert asec(nan) is nan + assert asec(1) == 0 + assert asec(-1) == pi + assert asec(oo) == pi/2 + assert asec(-oo) == pi/2 + assert asec(zoo) == pi/2 + + assert asec(sec(pi*Rational(13, 4))) == pi*Rational(3, 4) + assert asec(1 + sqrt(5)) == pi*Rational(2, 5) + assert asec(2/sqrt(3)) == pi/6 + assert asec(sqrt(4 - 2*sqrt(2))) == pi/8 + assert asec(-sqrt(4 + 2*sqrt(2))) == pi*Rational(5, 8) + assert asec(sqrt(2 + 2*sqrt(5)/5)) == pi*Rational(3, 10) + assert asec(-sqrt(2 + 2*sqrt(5)/5)) == pi*Rational(7, 10) + assert asec(sqrt(2) - sqrt(6)) == pi*Rational(11, 12) + + for d in [3, 4, 6]: + for num in range(d): + if gcd(num, d) == 1: + assert asec(sec(num*pi/d)) == num*pi/d + assert asec(-sec(num*pi/d)) == pi - num*pi/d + assert asec(csc(num*pi/d)) == pi/2 - acsc(csc(num*pi/d)) + assert asec(-csc(num*pi/d)) == pi/2 - acsc(-csc(num*pi/d)) + + assert asec(x).diff(x) == 1/(x**2*sqrt(1 - 1/x**2)) + + assert asec(x).rewrite(log) == I*log(sqrt(1 - 1/x**2) + I/x) + pi/2 + assert asec(x).rewrite(asin) == -asin(1/x) + pi/2 + assert asec(x).rewrite(acos) == acos(1/x) + assert asec(x).rewrite(atan) == \ + pi*(1 - sqrt(x**2)/x)/2 + sqrt(x**2)*atan(sqrt(x**2 - 1))/x + assert asec(x).rewrite(acot) == \ + pi*(1 - sqrt(x**2)/x)/2 + sqrt(x**2)*acot(1/sqrt(x**2 - 1))/x + assert asec(x).rewrite(acsc) == -acsc(x) + pi/2 + raises(ArgumentIndexError, lambda: asec(x).fdiff(2)) + + +def test_asec_is_real(): + assert asec(S.Half).is_real is False + n = Symbol('n', positive=True, integer=True) + assert asec(n).is_extended_real is True + assert asec(x).is_real is None + assert asec(r).is_real is None + t = Symbol('t', real=False, finite=True) + assert asec(t).is_real is False + + +def test_asec_leading_term(): + assert asec(1/x).as_leading_term(x) == pi/2 + # Tests concerning branch points + assert asec(x + 1).as_leading_term(x) == sqrt(2)*sqrt(x) + assert asec(x - 1).as_leading_term(x) == pi + # Tests concerning points lying on branch cuts + assert asec(x).as_leading_term(x, cdir=1) == -I*log(x) + I*log(2) + assert asec(x).as_leading_term(x, cdir=-1) == I*log(x) + 2*pi - I*log(2) + assert asec(I*x + 1/2).as_leading_term(x, cdir=1) == asec(1/2) + assert asec(-I*x + 1/2).as_leading_term(x, cdir=1) == -asec(1/2) + assert asec(I*x - 1/2).as_leading_term(x, cdir=1) == 2*pi - asec(-1/2) + assert asec(-I*x - 1/2).as_leading_term(x, cdir=1) == asec(-1/2) + # Tests concerning im(ndir) == 0 + assert asec(-I*x**2 + x - S(1)/2).as_leading_term(x, cdir=1) == pi + I*log(2 - sqrt(3)) + assert asec(-I*x**2 + x - S(1)/2).as_leading_term(x, cdir=-1) == pi + I*log(2 - sqrt(3)) + + +def test_asec_series(): + assert asec(x).series(x, 0, 9) == \ + I*log(2) - I*log(x) - I*x**2/4 - 3*I*x**4/32 \ + - 5*I*x**6/96 - 35*I*x**8/1024 + O(x**9) + t4 = asec(x).taylor_term(4, x) + assert t4 == -3*I*x**4/32 + assert asec(x).taylor_term(6, x, t4, 0) == -5*I*x**6/96 + + +def test_acsc(): + assert acsc(nan) is nan + assert acsc(1) == pi/2 + assert acsc(-1) == -pi/2 + assert acsc(oo) == 0 + assert acsc(-oo) == 0 + assert acsc(zoo) == 0 + assert acsc(0) is zoo + + assert acsc(csc(3)) == -3 + pi + assert acsc(csc(4)) == -4 + pi + assert acsc(csc(6)) == 6 - 2*pi + assert unchanged(acsc, csc(x)) + assert unchanged(acsc, sec(x)) + + assert acsc(2/sqrt(3)) == pi/3 + assert acsc(csc(pi*Rational(13, 4))) == -pi/4 + assert acsc(sqrt(2 + 2*sqrt(5)/5)) == pi/5 + assert acsc(-sqrt(2 + 2*sqrt(5)/5)) == -pi/5 + assert acsc(-2) == -pi/6 + assert acsc(-sqrt(4 + 2*sqrt(2))) == -pi/8 + assert acsc(sqrt(4 - 2*sqrt(2))) == pi*Rational(3, 8) + assert acsc(1 + sqrt(5)) == pi/10 + assert acsc(sqrt(2) - sqrt(6)) == pi*Rational(-5, 12) + + assert acsc(x).diff(x) == -1/(x**2*sqrt(1 - 1/x**2)) + + assert acsc(x).rewrite(log) == -I*log(sqrt(1 - 1/x**2) + I/x) + assert acsc(x).rewrite(asin) == asin(1/x) + assert acsc(x).rewrite(acos) == -acos(1/x) + pi/2 + assert acsc(x).rewrite(atan) == \ + (-atan(sqrt(x**2 - 1)) + pi/2)*sqrt(x**2)/x + assert acsc(x).rewrite(acot) == (-acot(1/sqrt(x**2 - 1)) + pi/2)*sqrt(x**2)/x + assert acsc(x).rewrite(asec) == -asec(x) + pi/2 + raises(ArgumentIndexError, lambda: acsc(x).fdiff(2)) + + +def test_csc_rewrite(): + assert csc(x).rewrite(pow) == csc(x) + assert csc(x).rewrite(sqrt) == csc(x) + + assert csc(x).rewrite(exp) == 2*I/(exp(I*x) - exp(-I*x)) + assert csc(x).rewrite(sin) == 1/sin(x) + assert csc(x).rewrite(tan) == (tan(x/2)**2 + 1)/(2*tan(x/2)) + assert csc(x).rewrite(cot) == (cot(x/2)**2 + 1)/(2*cot(x/2)) + assert csc(x).rewrite(cos) == 1/cos(x - pi/2, evaluate=False) + assert csc(x).rewrite(sec) == sec(-x + pi/2, evaluate=False) + + # issue 17349 + assert csc(1 - exp(-besselj(I, I))).rewrite(cos) == \ + -1/cos(-pi/2 - 1 + cos(I*besselj(I, I)) + + I*cos(-pi/2 + I*besselj(I, I), evaluate=False), evaluate=False) + assert csc(x).rewrite(besselj) == sqrt(2)/(sqrt(pi*x)*besselj(S.Half, x)) + assert csc(x).rewrite(besselj).subs(x, 0) == csc(0) + + +def test_acsc_leading_term(): + assert acsc(1/x).as_leading_term(x) == x + # Tests concerning branch points + assert acsc(x + 1).as_leading_term(x) == pi/2 + assert acsc(x - 1).as_leading_term(x) == -pi/2 + # Tests concerning points lying on branch cuts + assert acsc(x).as_leading_term(x, cdir=1) == I*log(x) + pi/2 - I*log(2) + assert acsc(x).as_leading_term(x, cdir=-1) == -I*log(x) - 3*pi/2 + I*log(2) + assert acsc(I*x + 1/2).as_leading_term(x, cdir=1) == acsc(1/2) + assert acsc(-I*x + 1/2).as_leading_term(x, cdir=1) == pi - acsc(1/2) + assert acsc(I*x - 1/2).as_leading_term(x, cdir=1) == -pi - acsc(-1/2) + assert acsc(-I*x - 1/2).as_leading_term(x, cdir=1) == -acsc(1/2) + # Tests concerning im(ndir) == 0 + assert acsc(-I*x**2 + x - S(1)/2).as_leading_term(x, cdir=1) == -pi/2 + I*log(sqrt(3) + 2) + assert acsc(-I*x**2 + x - S(1)/2).as_leading_term(x, cdir=-1) == -pi/2 + I*log(sqrt(3) + 2) + + +def test_acsc_series(): + assert acsc(x).series(x, 0, 9) == \ + -I*log(2) + pi/2 + I*log(x) + I*x**2/4 \ + + 3*I*x**4/32 + 5*I*x**6/96 + 35*I*x**8/1024 + O(x**9) + t6 = acsc(x).taylor_term(6, x) + assert t6 == 5*I*x**6/96 + assert acsc(x).taylor_term(8, x, t6, 0) == 35*I*x**8/1024 + + +def test_asin_nseries(): + assert asin(x + 2)._eval_nseries(x, 4, None, I) == -asin(2) + pi + \ + sqrt(3)*I*x/3 - sqrt(3)*I*x**2/9 + sqrt(3)*I*x**3/18 + O(x**4) + assert asin(x + 2)._eval_nseries(x, 4, None, -I) == asin(2) - \ + sqrt(3)*I*x/3 + sqrt(3)*I*x**2/9 - sqrt(3)*I*x**3/18 + O(x**4) + assert asin(x - 2)._eval_nseries(x, 4, None, I) == -asin(2) - \ + sqrt(3)*I*x/3 - sqrt(3)*I*x**2/9 - sqrt(3)*I*x**3/18 + O(x**4) + assert asin(x - 2)._eval_nseries(x, 4, None, -I) == asin(2) - pi + \ + sqrt(3)*I*x/3 + sqrt(3)*I*x**2/9 + sqrt(3)*I*x**3/18 + O(x**4) + # testing nseries for asin at branch points + assert asin(1 + x)._eval_nseries(x, 3, None) == pi/2 - sqrt(2)*sqrt(-x) - \ + sqrt(2)*(-x)**(S(3)/2)/12 - 3*sqrt(2)*(-x)**(S(5)/2)/160 + O(x**3) + assert asin(-1 + x)._eval_nseries(x, 3, None) == -pi/2 + sqrt(2)*sqrt(x) + \ + sqrt(2)*x**(S(3)/2)/12 + 3*sqrt(2)*x**(S(5)/2)/160 + O(x**3) + assert asin(exp(x))._eval_nseries(x, 3, None) == pi/2 - sqrt(2)*sqrt(-x) + \ + sqrt(2)*(-x)**(S(3)/2)/6 - sqrt(2)*(-x)**(S(5)/2)/120 + O(x**3) + assert asin(-exp(x))._eval_nseries(x, 3, None) == -pi/2 + sqrt(2)*sqrt(-x) - \ + sqrt(2)*(-x)**(S(3)/2)/6 + sqrt(2)*(-x)**(S(5)/2)/120 + O(x**3) + + +def test_acos_nseries(): + assert acos(x + 2)._eval_nseries(x, 4, None, I) == -acos(2) - sqrt(3)*I*x/3 + \ + sqrt(3)*I*x**2/9 - sqrt(3)*I*x**3/18 + O(x**4) + assert acos(x + 2)._eval_nseries(x, 4, None, -I) == acos(2) + sqrt(3)*I*x/3 - \ + sqrt(3)*I*x**2/9 + sqrt(3)*I*x**3/18 + O(x**4) + assert acos(x - 2)._eval_nseries(x, 4, None, I) == acos(-2) + sqrt(3)*I*x/3 + \ + sqrt(3)*I*x**2/9 + sqrt(3)*I*x**3/18 + O(x**4) + assert acos(x - 2)._eval_nseries(x, 4, None, -I) == -acos(-2) + 2*pi - \ + sqrt(3)*I*x/3 - sqrt(3)*I*x**2/9 - sqrt(3)*I*x**3/18 + O(x**4) + # testing nseries for acos at branch points + assert acos(1 + x)._eval_nseries(x, 3, None) == sqrt(2)*sqrt(-x) + \ + sqrt(2)*(-x)**(S(3)/2)/12 + 3*sqrt(2)*(-x)**(S(5)/2)/160 + O(x**3) + assert acos(-1 + x)._eval_nseries(x, 3, None) == pi - sqrt(2)*sqrt(x) - \ + sqrt(2)*x**(S(3)/2)/12 - 3*sqrt(2)*x**(S(5)/2)/160 + O(x**3) + assert acos(exp(x))._eval_nseries(x, 3, None) == sqrt(2)*sqrt(-x) - \ + sqrt(2)*(-x)**(S(3)/2)/6 + sqrt(2)*(-x)**(S(5)/2)/120 + O(x**3) + assert acos(-exp(x))._eval_nseries(x, 3, None) == pi - sqrt(2)*sqrt(-x) + \ + sqrt(2)*(-x)**(S(3)/2)/6 - sqrt(2)*(-x)**(S(5)/2)/120 + O(x**3) + + +def test_atan_nseries(): + assert atan(x + 2*I)._eval_nseries(x, 4, None, 1) == I*atanh(2) - x/3 - \ + 2*I*x**2/9 + 13*x**3/81 + O(x**4) + assert atan(x + 2*I)._eval_nseries(x, 4, None, -1) == I*atanh(2) - pi - \ + x/3 - 2*I*x**2/9 + 13*x**3/81 + O(x**4) + assert atan(x - 2*I)._eval_nseries(x, 4, None, 1) == -I*atanh(2) + pi - \ + x/3 + 2*I*x**2/9 + 13*x**3/81 + O(x**4) + assert atan(x - 2*I)._eval_nseries(x, 4, None, -1) == -I*atanh(2) - x/3 + \ + 2*I*x**2/9 + 13*x**3/81 + O(x**4) + assert atan(1/x)._eval_nseries(x, 2, None, 1) == pi/2 - x + O(x**2) + assert atan(1/x)._eval_nseries(x, 2, None, -1) == -pi/2 - x + O(x**2) + # testing nseries for atan at branch points + assert atan(x + I)._eval_nseries(x, 4, None) == I*log(2)/2 + pi/4 - \ + I*log(x)/2 + x/4 + I*x**2/16 - x**3/48 + O(x**4) + assert atan(x - I)._eval_nseries(x, 4, None) == -I*log(2)/2 + pi/4 + \ + I*log(x)/2 + x/4 - I*x**2/16 - x**3/48 + O(x**4) + + +def test_acot_nseries(): + assert acot(x + S(1)/2*I)._eval_nseries(x, 4, None, 1) == -I*acoth(S(1)/2) + \ + pi - 4*x/3 + 8*I*x**2/9 + 112*x**3/81 + O(x**4) + assert acot(x + S(1)/2*I)._eval_nseries(x, 4, None, -1) == -I*acoth(S(1)/2) - \ + 4*x/3 + 8*I*x**2/9 + 112*x**3/81 + O(x**4) + assert acot(x - S(1)/2*I)._eval_nseries(x, 4, None, 1) == I*acoth(S(1)/2) - \ + 4*x/3 - 8*I*x**2/9 + 112*x**3/81 + O(x**4) + assert acot(x - S(1)/2*I)._eval_nseries(x, 4, None, -1) == I*acoth(S(1)/2) - \ + pi - 4*x/3 - 8*I*x**2/9 + 112*x**3/81 + O(x**4) + assert acot(x)._eval_nseries(x, 2, None, 1) == pi/2 - x + O(x**2) + assert acot(x)._eval_nseries(x, 2, None, -1) == -pi/2 - x + O(x**2) + # testing nseries for acot at branch points + assert acot(x + I)._eval_nseries(x, 4, None) == -I*log(2)/2 + pi/4 + \ + I*log(x)/2 - x/4 - I*x**2/16 + x**3/48 + O(x**4) + assert acot(x - I)._eval_nseries(x, 4, None) == I*log(2)/2 + pi/4 - \ + I*log(x)/2 - x/4 + I*x**2/16 + x**3/48 + O(x**4) + + +def test_asec_nseries(): + assert asec(x + S(1)/2)._eval_nseries(x, 4, None, I) == asec(S(1)/2) - \ + 4*sqrt(3)*I*x/3 + 8*sqrt(3)*I*x**2/9 - 16*sqrt(3)*I*x**3/9 + O(x**4) + assert asec(x + S(1)/2)._eval_nseries(x, 4, None, -I) == -asec(S(1)/2) + \ + 4*sqrt(3)*I*x/3 - 8*sqrt(3)*I*x**2/9 + 16*sqrt(3)*I*x**3/9 + O(x**4) + assert asec(x - S(1)/2)._eval_nseries(x, 4, None, I) == -asec(-S(1)/2) + \ + 2*pi + 4*sqrt(3)*I*x/3 + 8*sqrt(3)*I*x**2/9 + 16*sqrt(3)*I*x**3/9 + O(x**4) + assert asec(x - S(1)/2)._eval_nseries(x, 4, None, -I) == asec(-S(1)/2) - \ + 4*sqrt(3)*I*x/3 - 8*sqrt(3)*I*x**2/9 - 16*sqrt(3)*I*x**3/9 + O(x**4) + # testing nseries for asec at branch points + assert asec(1 + x)._eval_nseries(x, 3, None) == sqrt(2)*sqrt(x) - \ + 5*sqrt(2)*x**(S(3)/2)/12 + 43*sqrt(2)*x**(S(5)/2)/160 + O(x**3) + assert asec(-1 + x)._eval_nseries(x, 3, None) == pi - sqrt(2)*sqrt(-x) + \ + 5*sqrt(2)*(-x)**(S(3)/2)/12 - 43*sqrt(2)*(-x)**(S(5)/2)/160 + O(x**3) + assert asec(exp(x))._eval_nseries(x, 3, None) == sqrt(2)*sqrt(x) - \ + sqrt(2)*x**(S(3)/2)/6 + sqrt(2)*x**(S(5)/2)/120 + O(x**3) + assert asec(-exp(x))._eval_nseries(x, 3, None) == pi - sqrt(2)*sqrt(x) + \ + sqrt(2)*x**(S(3)/2)/6 - sqrt(2)*x**(S(5)/2)/120 + O(x**3) + + +def test_acsc_nseries(): + assert acsc(x + S(1)/2)._eval_nseries(x, 4, None, I) == acsc(S(1)/2) + \ + 4*sqrt(3)*I*x/3 - 8*sqrt(3)*I*x**2/9 + 16*sqrt(3)*I*x**3/9 + O(x**4) + assert acsc(x + S(1)/2)._eval_nseries(x, 4, None, -I) == -acsc(S(1)/2) + \ + pi - 4*sqrt(3)*I*x/3 + 8*sqrt(3)*I*x**2/9 - 16*sqrt(3)*I*x**3/9 + O(x**4) + assert acsc(x - S(1)/2)._eval_nseries(x, 4, None, I) == acsc(S(1)/2) - pi -\ + 4*sqrt(3)*I*x/3 - 8*sqrt(3)*I*x**2/9 - 16*sqrt(3)*I*x**3/9 + O(x**4) + assert acsc(x - S(1)/2)._eval_nseries(x, 4, None, -I) == -acsc(S(1)/2) + \ + 4*sqrt(3)*I*x/3 + 8*sqrt(3)*I*x**2/9 + 16*sqrt(3)*I*x**3/9 + O(x**4) + # testing nseries for acsc at branch points + assert acsc(1 + x)._eval_nseries(x, 3, None) == pi/2 - sqrt(2)*sqrt(x) + \ + 5*sqrt(2)*x**(S(3)/2)/12 - 43*sqrt(2)*x**(S(5)/2)/160 + O(x**3) + assert acsc(-1 + x)._eval_nseries(x, 3, None) == -pi/2 + sqrt(2)*sqrt(-x) - \ + 5*sqrt(2)*(-x)**(S(3)/2)/12 + 43*sqrt(2)*(-x)**(S(5)/2)/160 + O(x**3) + assert acsc(exp(x))._eval_nseries(x, 3, None) == pi/2 - sqrt(2)*sqrt(x) + \ + sqrt(2)*x**(S(3)/2)/6 - sqrt(2)*x**(S(5)/2)/120 + O(x**3) + assert acsc(-exp(x))._eval_nseries(x, 3, None) == -pi/2 + sqrt(2)*sqrt(x) - \ + sqrt(2)*x**(S(3)/2)/6 + sqrt(2)*x**(S(5)/2)/120 + O(x**3) + + +def test_issue_8653(): + n = Symbol('n', integer=True) + assert sin(n).is_irrational is None + assert cos(n).is_irrational is None + assert tan(n).is_irrational is None + + +def test_issue_9157(): + n = Symbol('n', integer=True, positive=True) + assert atan(n - 1).is_nonnegative is True + + +def test_trig_period(): + x, y = symbols('x, y') + + assert sin(x).period() == 2*pi + assert cos(x).period() == 2*pi + assert tan(x).period() == pi + assert cot(x).period() == pi + assert sec(x).period() == 2*pi + assert csc(x).period() == 2*pi + assert sin(2*x).period() == pi + assert cot(4*x - 6).period() == pi/4 + assert cos((-3)*x).period() == pi*Rational(2, 3) + assert cos(x*y).period(x) == 2*pi/abs(y) + assert sin(3*x*y + 2*pi).period(y) == 2*pi/abs(3*x) + assert tan(3*x).period(y) is S.Zero + raises(NotImplementedError, lambda: sin(x**2).period(x)) + + +def test_issue_7171(): + assert sin(x).rewrite(sqrt) == sin(x) + assert sin(x).rewrite(pow) == sin(x) + + +def test_issue_11864(): + w, k = symbols('w, k', real=True) + F = Piecewise((1, Eq(2*pi*k, 0)), (sin(pi*k)/(pi*k), True)) + soln = Piecewise((1, Eq(2*pi*k, 0)), (sinc(pi*k), True)) + assert F.rewrite(sinc) == soln + +def test_real_assumptions(): + z = Symbol('z', real=False, finite=True) + assert sin(z).is_real is None + assert cos(z).is_real is None + assert tan(z).is_real is False + assert sec(z).is_real is None + assert csc(z).is_real is None + assert cot(z).is_real is False + assert asin(p).is_real is None + assert asin(n).is_real is None + assert asec(p).is_real is None + assert asec(n).is_real is None + assert acos(p).is_real is None + assert acos(n).is_real is None + assert acsc(p).is_real is None + assert acsc(n).is_real is None + assert atan(p).is_positive is True + assert atan(n).is_negative is True + assert acot(p).is_positive is True + assert acot(n).is_negative is True + +def test_issue_14320(): + assert asin(sin(2)) == -2 + pi and (-pi/2 <= -2 + pi <= pi/2) and sin(2) == sin(-2 + pi) + assert asin(cos(2)) == -2 + pi/2 and (-pi/2 <= -2 + pi/2 <= pi/2) and cos(2) == sin(-2 + pi/2) + assert acos(sin(2)) == -pi/2 + 2 and (0 <= -pi/2 + 2 <= pi) and sin(2) == cos(-pi/2 + 2) + assert acos(cos(20)) == -6*pi + 20 and (0 <= -6*pi + 20 <= pi) and cos(20) == cos(-6*pi + 20) + assert acos(cos(30)) == -30 + 10*pi and (0 <= -30 + 10*pi <= pi) and cos(30) == cos(-30 + 10*pi) + + assert atan(tan(17)) == -5*pi + 17 and (-pi/2 < -5*pi + 17 < pi/2) and tan(17) == tan(-5*pi + 17) + assert atan(tan(15)) == -5*pi + 15 and (-pi/2 < -5*pi + 15 < pi/2) and tan(15) == tan(-5*pi + 15) + assert atan(cot(12)) == -12 + pi*Rational(7, 2) and (-pi/2 < -12 + pi*Rational(7, 2) < pi/2) and cot(12) == tan(-12 + pi*Rational(7, 2)) + assert acot(cot(15)) == -5*pi + 15 and (-pi/2 < -5*pi + 15 <= pi/2) and cot(15) == cot(-5*pi + 15) + assert acot(tan(19)) == -19 + pi*Rational(13, 2) and (-pi/2 < -19 + pi*Rational(13, 2) <= pi/2) and tan(19) == cot(-19 + pi*Rational(13, 2)) + + assert asec(sec(11)) == -11 + 4*pi and (0 <= -11 + 4*pi <= pi) and cos(11) == cos(-11 + 4*pi) + assert asec(csc(13)) == -13 + pi*Rational(9, 2) and (0 <= -13 + pi*Rational(9, 2) <= pi) and sin(13) == cos(-13 + pi*Rational(9, 2)) + assert acsc(csc(14)) == -4*pi + 14 and (-pi/2 <= -4*pi + 14 <= pi/2) and sin(14) == sin(-4*pi + 14) + assert acsc(sec(10)) == pi*Rational(-7, 2) + 10 and (-pi/2 <= pi*Rational(-7, 2) + 10 <= pi/2) and cos(10) == sin(pi*Rational(-7, 2) + 10) + +def test_issue_14543(): + assert sec(2*pi + 11) == sec(11) + assert sec(2*pi - 11) == sec(11) + assert sec(pi + 11) == -sec(11) + assert sec(pi - 11) == -sec(11) + + assert csc(2*pi + 17) == csc(17) + assert csc(2*pi - 17) == -csc(17) + assert csc(pi + 17) == -csc(17) + assert csc(pi - 17) == csc(17) + + x = Symbol('x') + assert csc(pi/2 + x) == sec(x) + assert csc(pi/2 - x) == sec(x) + assert csc(pi*Rational(3, 2) + x) == -sec(x) + assert csc(pi*Rational(3, 2) - x) == -sec(x) + + assert sec(pi/2 - x) == csc(x) + assert sec(pi/2 + x) == -csc(x) + assert sec(pi*Rational(3, 2) + x) == csc(x) + assert sec(pi*Rational(3, 2) - x) == -csc(x) + + +def test_as_real_imag(): + # This is for https://github.com/sympy/sympy/issues/17142 + # If it start failing again in irrelevant builds or in the master + # please open up the issue again. + expr = atan(I/(I + I*tan(1))) + assert expr.as_real_imag() == (expr, 0) + + +def test_issue_18746(): + e3 = cos(S.Pi*(x/4 + 1/4)) + assert e3.period() == 8 + + +def test_issue_25833(): + assert limit(atan(x**2), x, oo) == pi/2 + assert limit(atan(x**2 - 1), x, oo) == pi/2 + assert limit(atan(log(2**x)/log(2*x)), x, oo) == pi/2 + + +def test_issue_25847(): + #atan + assert atan(sin(x)/x).as_leading_term(x) == pi/4 + raises(PoleError, lambda: atan(exp(1/x)).as_leading_term(x)) + + #asin + assert asin(sin(x)/x).as_leading_term(x) == pi/2 + raises(PoleError, lambda: asin(exp(1/x)).as_leading_term(x)) + + #acos + assert acos(sin(x)/x).as_leading_term(x) == 0 + raises(PoleError, lambda: acos(exp(1/x)).as_leading_term(x)) + + #acot + assert acot(sin(x)/x).as_leading_term(x) == pi/4 + raises(PoleError, lambda: acot(exp(1/x)).as_leading_term(x)) + + #asec + assert asec(sin(x)/x).as_leading_term(x) == 0 + raises(PoleError, lambda: asec(exp(1/x)).as_leading_term(x)) + + #acsc + assert acsc(sin(x)/x).as_leading_term(x) == pi/2 + raises(PoleError, lambda: acsc(exp(1/x)).as_leading_term(x)) + +def test_issue_23843(): + #atan + assert atan(x + I).series(x, oo) == -16/(5*x**5) - 2*I/x**4 + 4/(3*x**3) + I/x**2 - 1/x + pi/2 + O(x**(-6), (x, oo)) + assert atan(x + I).series(x, -oo) == -16/(5*x**5) - 2*I/x**4 + 4/(3*x**3) + I/x**2 - 1/x - pi/2 + O(x**(-6), (x, -oo)) + assert atan(x - I).series(x, oo) == -16/(5*x**5) + 2*I/x**4 + 4/(3*x**3) - I/x**2 - 1/x + pi/2 + O(x**(-6), (x, oo)) + assert atan(x - I).series(x, -oo) == -16/(5*x**5) + 2*I/x**4 + 4/(3*x**3) - I/x**2 - 1/x - pi/2 + O(x**(-6), (x, -oo)) + + #acot + assert acot(x + I).series(x, oo) == 16/(5*x**5) + 2*I/x**4 - 4/(3*x**3) - I/x**2 + 1/x + O(x**(-6), (x, oo)) + assert acot(x + I).series(x, -oo) == 16/(5*x**5) + 2*I/x**4 - 4/(3*x**3) - I/x**2 + 1/x + O(x**(-6), (x, -oo)) + assert acot(x - I).series(x, oo) == 16/(5*x**5) - 2*I/x**4 - 4/(3*x**3) + I/x**2 + 1/x + O(x**(-6), (x, oo)) + assert acot(x - I).series(x, -oo) == 16/(5*x**5) - 2*I/x**4 - 4/(3*x**3) + I/x**2 + 1/x + O(x**(-6), (x, -oo)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/trigonometric.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/trigonometric.py new file mode 100644 index 0000000000000000000000000000000000000000..24e5db81f17a215f5b344291f0e9bf4752e5317d --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/elementary/trigonometric.py @@ -0,0 +1,3627 @@ +from __future__ import annotations +from sympy.core.add import Add +from sympy.core.cache import cacheit +from sympy.core.expr import Expr +from sympy.core.function import DefinedFunction, ArgumentIndexError, PoleError, expand_mul +from sympy.core.logic import fuzzy_not, fuzzy_or, FuzzyBool, fuzzy_and +from sympy.core.mod import Mod +from sympy.core.numbers import Rational, pi, Integer, Float, equal_valued +from sympy.core.relational import Ne, Eq +from sympy.core.singleton import S +from sympy.core.symbol import Symbol, Dummy +from sympy.core.sympify import sympify +from sympy.functions.combinatorial.factorials import factorial, RisingFactorial +from sympy.functions.combinatorial.numbers import bernoulli, euler +from sympy.functions.elementary.complexes import arg as arg_f, im, re +from sympy.functions.elementary.exponential import log, exp +from sympy.functions.elementary.integers import floor +from sympy.functions.elementary.miscellaneous import sqrt, Min, Max +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary._trigonometric_special import ( + cos_table, ipartfrac, fermat_coords) +from sympy.logic.boolalg import And +from sympy.ntheory import factorint +from sympy.polys.specialpolys import symmetric_poly +from sympy.utilities.iterables import numbered_symbols + + +############################################################################### +########################## UTILITIES ########################################## +############################################################################### + + +def _imaginary_unit_as_coefficient(arg): + """ Helper to extract symbolic coefficient for imaginary unit """ + if isinstance(arg, Float): + return None + else: + return arg.as_coefficient(S.ImaginaryUnit) + +############################################################################### +########################## TRIGONOMETRIC FUNCTIONS ############################ +############################################################################### + + +class TrigonometricFunction(DefinedFunction): + """Base class for trigonometric functions. """ + + unbranched = True + _singularities = (S.ComplexInfinity,) + + def _eval_is_rational(self): + s = self.func(*self.args) + if s.func == self.func: + if s.args[0].is_rational and fuzzy_not(s.args[0].is_zero): + return False + else: + return s.is_rational + + def _eval_is_algebraic(self): + s = self.func(*self.args) + if s.func == self.func: + if fuzzy_not(self.args[0].is_zero) and self.args[0].is_algebraic: + return False + pi_coeff = _pi_coeff(self.args[0]) + if pi_coeff is not None and pi_coeff.is_rational: + return True + else: + return s.is_algebraic + + def _eval_expand_complex(self, deep=True, **hints): + re_part, im_part = self.as_real_imag(deep=deep, **hints) + return re_part + im_part*S.ImaginaryUnit + + def _as_real_imag(self, deep=True, **hints): + if self.args[0].is_extended_real: + if deep: + hints['complex'] = False + return (self.args[0].expand(deep, **hints), S.Zero) + else: + return (self.args[0], S.Zero) + if deep: + re, im = self.args[0].expand(deep, **hints).as_real_imag() + else: + re, im = self.args[0].as_real_imag() + return (re, im) + + def _period(self, general_period, symbol=None): + f = expand_mul(self.args[0]) + if symbol is None: + symbol = tuple(f.free_symbols)[0] + + if not f.has(symbol): + return S.Zero + + if f == symbol: + return general_period + + if symbol in f.free_symbols: + if f.is_Mul: + g, h = f.as_independent(symbol) + if h == symbol: + return general_period/abs(g) + + if f.is_Add: + a, h = f.as_independent(symbol) + g, h = h.as_independent(symbol, as_Add=False) + if h == symbol: + return general_period/abs(g) + + raise NotImplementedError("Use the periodicity function instead.") + + +@cacheit +def _table2(): + # If nested sqrt's are worse than un-evaluation + # you can require q to be in (1, 2, 3, 4, 6, 12) + # q <= 12, q=15, q=20, q=24, q=30, q=40, q=60, q=120 return + # expressions with 2 or fewer sqrt nestings. + return { + 12: (3, 4), + 20: (4, 5), + 30: (5, 6), + 15: (6, 10), + 24: (6, 8), + 40: (8, 10), + 60: (20, 30), + 120: (40, 60) + } + + +def _peeloff_pi(arg): + r""" + Split ARG into two parts, a "rest" and a multiple of $\pi$. + This assumes ARG to be an Add. + The multiple of $\pi$ returned in the second position is always a Rational. + + Examples + ======== + + >>> from sympy.functions.elementary.trigonometric import _peeloff_pi + >>> from sympy import pi + >>> from sympy.abc import x, y + >>> _peeloff_pi(x + pi/2) + (x, 1/2) + >>> _peeloff_pi(x + 2*pi/3 + pi*y) + (x + pi*y + pi/6, 1/2) + + """ + pi_coeff = S.Zero + rest_terms = [] + for a in Add.make_args(arg): + K = a.coeff(pi) + if K and K.is_rational: + pi_coeff += K + else: + rest_terms.append(a) + + if pi_coeff is S.Zero: + return arg, S.Zero + + m1 = (pi_coeff % S.Half) + m2 = pi_coeff - m1 + if m2.is_integer or ((2*m2).is_integer and m2.is_even is False): + return Add(*(rest_terms + [m1*pi])), m2 + return arg, S.Zero + + +def _pi_coeff(arg: Expr, cycles: int = 1) -> Expr | None: + r""" + When arg is a Number times $\pi$ (e.g. $3\pi/2$) then return the Number + normalized to be in the range $[0, 2]$, else `None`. + + When an even multiple of $\pi$ is encountered, if it is multiplying + something with known parity then the multiple is returned as 0 otherwise + as 2. + + Examples + ======== + + >>> from sympy.functions.elementary.trigonometric import _pi_coeff + >>> from sympy import pi, Dummy + >>> from sympy.abc import x + >>> _pi_coeff(3*x*pi) + 3*x + >>> _pi_coeff(11*pi/7) + 11/7 + >>> _pi_coeff(-11*pi/7) + 3/7 + >>> _pi_coeff(4*pi) + 0 + >>> _pi_coeff(5*pi) + 1 + >>> _pi_coeff(5.0*pi) + 1 + >>> _pi_coeff(5.5*pi) + 3/2 + >>> _pi_coeff(2 + pi) + + >>> _pi_coeff(2*Dummy(integer=True)*pi) + 2 + >>> _pi_coeff(2*Dummy(even=True)*pi) + 0 + + """ + if arg is pi: + return S.One + elif not arg: + return S.Zero + elif arg.is_Mul: + cx = arg.coeff(pi) + if cx: + c, x = cx.as_coeff_Mul() # pi is not included as coeff + if c.is_Float: + # recast exact binary fractions to Rationals + f = abs(c) % 1 + if f != 0: + p = -int(round(log(f, 2).evalf())) + m = 2**p + cm = c*m + i = int(cm) + if equal_valued(i, cm): + c = Rational(i, m) + cx = c*x + else: + c = Rational(int(c)) + cx = c*x + if x.is_integer: + c2 = c % 2 + if c2 == 1: + return x + elif not c2: + if x.is_even is not None: # known parity + return S.Zero + return Integer(2) + else: + return c2*x + return cx + elif arg.is_zero: + return S.Zero + return None + + +class sin(TrigonometricFunction): + r""" + The sine function. + + Returns the sine of x (measured in radians). + + Explanation + =========== + + This function will evaluate automatically in the + case $x/\pi$ is some rational number [4]_. For example, + if $x$ is a multiple of $\pi$, $\pi/2$, $\pi/3$, $\pi/4$, and $\pi/6$. + + Examples + ======== + + >>> from sympy import sin, pi + >>> from sympy.abc import x + >>> sin(x**2).diff(x) + 2*x*cos(x**2) + >>> sin(1).diff(x) + 0 + >>> sin(pi) + 0 + >>> sin(pi/2) + 1 + >>> sin(pi/6) + 1/2 + >>> sin(pi/12) + -sqrt(2)/4 + sqrt(6)/4 + + + See Also + ======== + + csc, cos, sec, tan, cot + asin, acsc, acos, asec, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_functions + .. [2] https://dlmf.nist.gov/4.14 + .. [3] https://functions.wolfram.com/ElementaryFunctions/Sin + .. [4] https://mathworld.wolfram.com/TrigonometryAngles.html + + """ + + def period(self, symbol=None): + return self._period(2*pi, symbol) + + def fdiff(self, argindex=1): + if argindex == 1: + return cos(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + from sympy.calculus.accumulationbounds import AccumBounds + from sympy.sets.setexpr import SetExpr + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg.is_zero: + return S.Zero + elif arg in (S.Infinity, S.NegativeInfinity): + return AccumBounds(-1, 1) + + if arg is S.ComplexInfinity: + return S.NaN + + if isinstance(arg, AccumBounds): + from sympy.sets.sets import FiniteSet + min, max = arg.min, arg.max + d = floor(min/(2*pi)) + if min is not S.NegativeInfinity: + min = min - d*2*pi + if max is not S.Infinity: + max = max - d*2*pi + if AccumBounds(min, max).intersection(FiniteSet(pi/2, pi*Rational(5, 2))) \ + is not S.EmptySet and \ + AccumBounds(min, max).intersection(FiniteSet(pi*Rational(3, 2), + pi*Rational(7, 2))) is not S.EmptySet: + return AccumBounds(-1, 1) + elif AccumBounds(min, max).intersection(FiniteSet(pi/2, pi*Rational(5, 2))) \ + is not S.EmptySet: + return AccumBounds(Min(sin(min), sin(max)), 1) + elif AccumBounds(min, max).intersection(FiniteSet(pi*Rational(3, 2), pi*Rational(8, 2))) \ + is not S.EmptySet: + return AccumBounds(-1, Max(sin(min), sin(max))) + else: + return AccumBounds(Min(sin(min), sin(max)), + Max(sin(min), sin(max))) + elif isinstance(arg, SetExpr): + return arg._eval_func(cls) + + if arg.could_extract_minus_sign(): + return -cls(-arg) + + i_coeff = _imaginary_unit_as_coefficient(arg) + if i_coeff is not None: + from sympy.functions.elementary.hyperbolic import sinh + return S.ImaginaryUnit*sinh(i_coeff) + + pi_coeff = _pi_coeff(arg) + if pi_coeff is not None: + if pi_coeff.is_integer: + return S.Zero + + if (2*pi_coeff).is_integer: + # is_even-case handled above as then pi_coeff.is_integer, + # so check if known to be not even + if pi_coeff.is_even is False: + return S.NegativeOne**(pi_coeff - S.Half) + + if not pi_coeff.is_Rational: + narg = pi_coeff*pi + if narg != arg: + return cls(narg) + return None + + # https://github.com/sympy/sympy/issues/6048 + # transform a sine to a cosine, to avoid redundant code + if pi_coeff.is_Rational: + x = pi_coeff % 2 + if x > 1: + return -cls((x % 1)*pi) + if 2*x > 1: + return cls((1 - x)*pi) + narg = ((pi_coeff + Rational(3, 2)) % 2)*pi + result = cos(narg) + if not isinstance(result, cos): + return result + if pi_coeff*pi != arg: + return cls(pi_coeff*pi) + return None + + if arg.is_Add: + x, m = _peeloff_pi(arg) + if m: + m = m*pi + return sin(m)*cos(x) + cos(m)*sin(x) + + if arg.is_zero: + return S.Zero + + if isinstance(arg, asin): + return arg.args[0] + + if isinstance(arg, atan): + x = arg.args[0] + return x/sqrt(1 + x**2) + + if isinstance(arg, atan2): + y, x = arg.args + return y/sqrt(x**2 + y**2) + + if isinstance(arg, acos): + x = arg.args[0] + return sqrt(1 - x**2) + + if isinstance(arg, acot): + x = arg.args[0] + return 1/(sqrt(1 + 1/x**2)*x) + + if isinstance(arg, acsc): + x = arg.args[0] + return 1/x + + if isinstance(arg, asec): + x = arg.args[0] + return sqrt(1 - 1/x**2) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + + if len(previous_terms) > 2: + p = previous_terms[-2] + return -p*x**2/(n*(n - 1)) + else: + return S.NegativeOne**(n//2)*x**n/factorial(n) + + def _eval_nseries(self, x, n, logx, cdir=0): + arg = self.args[0] + if logx is not None: + arg = arg.subs(log(x), logx) + if arg.subs(x, 0).has(S.NaN, S.ComplexInfinity): + raise PoleError("Cannot expand %s around 0" % (self)) + return super()._eval_nseries(x, n=n, logx=logx, cdir=cdir) + + def _eval_rewrite_as_exp(self, arg, **kwargs): + from sympy.functions.elementary.hyperbolic import HyperbolicFunction + I = S.ImaginaryUnit + if isinstance(arg, (TrigonometricFunction, HyperbolicFunction)): + arg = arg.func(arg.args[0]).rewrite(exp) + return (exp(arg*I) - exp(-arg*I))/(2*I) + + def _eval_rewrite_as_Pow(self, arg, **kwargs): + if isinstance(arg, log): + I = S.ImaginaryUnit + x = arg.args[0] + return I*x**-I/2 - I*x**I /2 + + def _eval_rewrite_as_cos(self, arg, **kwargs): + return cos(arg - pi/2, evaluate=False) + + def _eval_rewrite_as_tan(self, arg, **kwargs): + tan_half = tan(S.Half*arg) + return 2*tan_half/(1 + tan_half**2) + + def _eval_rewrite_as_sincos(self, arg, **kwargs): + return sin(arg)*cos(arg)/cos(arg) + + def _eval_rewrite_as_cot(self, arg, **kwargs): + cot_half = cot(S.Half*arg) + return Piecewise((0, And(Eq(im(arg), 0), Eq(Mod(arg, pi), 0))), + (2*cot_half/(1 + cot_half**2), True)) + + def _eval_rewrite_as_pow(self, arg, **kwargs): + return self.rewrite(cos, **kwargs).rewrite(pow, **kwargs) + + def _eval_rewrite_as_sqrt(self, arg, **kwargs): + return self.rewrite(cos, **kwargs).rewrite(sqrt, **kwargs) + + def _eval_rewrite_as_csc(self, arg, **kwargs): + return 1/csc(arg) + + def _eval_rewrite_as_sec(self, arg, **kwargs): + return 1/sec(arg - pi/2, evaluate=False) + + def _eval_rewrite_as_sinc(self, arg, **kwargs): + return arg*sinc(arg) + + def _eval_rewrite_as_besselj(self, arg, **kwargs): + from sympy.functions.special.bessel import besselj + return sqrt(pi*arg/2)*besselj(S.Half, arg) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def as_real_imag(self, deep=True, **hints): + from sympy.functions.elementary.hyperbolic import cosh, sinh + re, im = self._as_real_imag(deep=deep, **hints) + return (sin(re)*cosh(im), cos(re)*sinh(im)) + + def _eval_expand_trig(self, **hints): + from sympy.functions.special.polynomials import chebyshevt, chebyshevu + arg = self.args[0] + x = None + if arg.is_Add: # TODO, implement more if deep stuff here + # TODO: Do this more efficiently for more than two terms + x, y = arg.as_two_terms() + sx = sin(x, evaluate=False)._eval_expand_trig() + sy = sin(y, evaluate=False)._eval_expand_trig() + cx = cos(x, evaluate=False)._eval_expand_trig() + cy = cos(y, evaluate=False)._eval_expand_trig() + return sx*cy + sy*cx + elif arg.is_Mul: + n, x = arg.as_coeff_Mul(rational=True) + if n.is_Integer: # n will be positive because of .eval + # canonicalization + + # See https://mathworld.wolfram.com/Multiple-AngleFormulas.html + if n.is_odd: + return S.NegativeOne**((n - 1)/2)*chebyshevt(n, sin(x)) + else: + return expand_mul(S.NegativeOne**(n/2 - 1)*cos(x)* + chebyshevu(n - 1, sin(x)), deep=False) + return sin(arg) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.accumulationbounds import AccumBounds + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + n = x0/pi + if n.is_integer: + lt = (arg - n*pi).as_leading_term(x) + return (S.NegativeOne**n)*lt + if x0 is S.ComplexInfinity: + x0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if x0 in [S.Infinity, S.NegativeInfinity]: + return AccumBounds(-1, 1) + return self.func(x0) if x0.is_finite else self + + def _eval_is_extended_real(self): + if self.args[0].is_extended_real: + return True + + def _eval_is_finite(self): + arg = self.args[0] + if arg.is_extended_real: + return True + + def _eval_is_zero(self): + rest, pi_mult = _peeloff_pi(self.args[0]) + if rest.is_zero: + return pi_mult.is_integer + + def _eval_is_complex(self): + if self.args[0].is_extended_real \ + or self.args[0].is_complex: + return True + + +class cos(TrigonometricFunction): + """ + The cosine function. + + Returns the cosine of x (measured in radians). + + Explanation + =========== + + See :func:`sin` for notes about automatic evaluation. + + Examples + ======== + + >>> from sympy import cos, pi + >>> from sympy.abc import x + >>> cos(x**2).diff(x) + -2*x*sin(x**2) + >>> cos(1).diff(x) + 0 + >>> cos(pi) + -1 + >>> cos(pi/2) + 0 + >>> cos(2*pi/3) + -1/2 + >>> cos(pi/12) + sqrt(2)/4 + sqrt(6)/4 + + See Also + ======== + + sin, csc, sec, tan, cot + asin, acsc, acos, asec, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_functions + .. [2] https://dlmf.nist.gov/4.14 + .. [3] https://functions.wolfram.com/ElementaryFunctions/Cos + + """ + + def period(self, symbol=None): + return self._period(2*pi, symbol) + + def fdiff(self, argindex=1): + if argindex == 1: + return -sin(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + from sympy.functions.special.polynomials import chebyshevt + from sympy.calculus.accumulationbounds import AccumBounds + from sympy.sets.setexpr import SetExpr + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg.is_zero: + return S.One + elif arg in (S.Infinity, S.NegativeInfinity): + # In this case it is better to return AccumBounds(-1, 1) + # rather than returning S.NaN, since AccumBounds(-1, 1) + # preserves the information that sin(oo) is between + # -1 and 1, where S.NaN does not do that. + return AccumBounds(-1, 1) + + if arg is S.ComplexInfinity: + return S.NaN + + if isinstance(arg, AccumBounds): + return sin(arg + pi/2) + elif isinstance(arg, SetExpr): + return arg._eval_func(cls) + + if arg.is_extended_real and arg.is_finite is False: + return AccumBounds(-1, 1) + + if arg.could_extract_minus_sign(): + return cls(-arg) + + i_coeff = _imaginary_unit_as_coefficient(arg) + if i_coeff is not None: + from sympy.functions.elementary.hyperbolic import cosh + return cosh(i_coeff) + + pi_coeff = _pi_coeff(arg) + if pi_coeff is not None: + if pi_coeff.is_integer: + return (S.NegativeOne)**pi_coeff + + if (2*pi_coeff).is_integer: + # is_even-case handled above as then pi_coeff.is_integer, + # so check if known to be not even + if pi_coeff.is_even is False: + return S.Zero + + if not pi_coeff.is_Rational: + narg = pi_coeff*pi + if narg != arg: + return cls(narg) + return None + + # cosine formula ##################### + # https://github.com/sympy/sympy/issues/6048 + # explicit calculations are performed for + # cos(k pi/n) for n = 8,10,12,15,20,24,30,40,60,120 + # Some other exact values like cos(k pi/240) can be + # calculated using a partial-fraction decomposition + # by calling cos( X ).rewrite(sqrt) + if pi_coeff.is_Rational: + q = pi_coeff.q + p = pi_coeff.p % (2*q) + if p > q: + narg = (pi_coeff - 1)*pi + return -cls(narg) + if 2*p > q: + narg = (1 - pi_coeff)*pi + return -cls(narg) + + # If nested sqrt's are worse than un-evaluation + # you can require q to be in (1, 2, 3, 4, 6, 12) + # q <= 12, q=15, q=20, q=24, q=30, q=40, q=60, q=120 return + # expressions with 2 or fewer sqrt nestings. + table2 = _table2() + if q in table2: + a, b = table2[q] + a, b = p*pi/a, p*pi/b + nvala, nvalb = cls(a), cls(b) + if None in (nvala, nvalb): + return None + return nvala*nvalb + cls(pi/2 - a)*cls(pi/2 - b) + + if q > 12: + return None + + cst_table_some = { + 3: S.Half, + 5: (sqrt(5) + 1) / 4, + } + if q in cst_table_some: + cts = cst_table_some[pi_coeff.q] + return chebyshevt(pi_coeff.p, cts).expand() + + if 0 == q % 2: + narg = (pi_coeff*2)*pi + nval = cls(narg) + if None == nval: + return None + x = (2*pi_coeff + 1)/2 + sign_cos = (-1)**((-1 if x < 0 else 1)*int(abs(x))) + return sign_cos*sqrt( (1 + nval)/2 ) + return None + + if arg.is_Add: + x, m = _peeloff_pi(arg) + if m: + m = m*pi + return cos(m)*cos(x) - sin(m)*sin(x) + + if arg.is_zero: + return S.One + + if isinstance(arg, acos): + return arg.args[0] + + if isinstance(arg, atan): + x = arg.args[0] + return 1/sqrt(1 + x**2) + + if isinstance(arg, atan2): + y, x = arg.args + return x/sqrt(x**2 + y**2) + + if isinstance(arg, asin): + x = arg.args[0] + return sqrt(1 - x ** 2) + + if isinstance(arg, acot): + x = arg.args[0] + return 1/sqrt(1 + 1/x**2) + + if isinstance(arg, acsc): + x = arg.args[0] + return sqrt(1 - 1/x**2) + + if isinstance(arg, asec): + x = arg.args[0] + return 1/x + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 1: + return S.Zero + else: + x = sympify(x) + + if len(previous_terms) > 2: + p = previous_terms[-2] + return -p*x**2/(n*(n - 1)) + else: + return S.NegativeOne**(n//2)*x**n/factorial(n) + + def _eval_nseries(self, x, n, logx, cdir=0): + arg = self.args[0] + if logx is not None: + arg = arg.subs(log(x), logx) + if arg.subs(x, 0).has(S.NaN, S.ComplexInfinity): + raise PoleError("Cannot expand %s around 0" % (self)) + return super()._eval_nseries(x, n=n, logx=logx, cdir=cdir) + + def _eval_rewrite_as_exp(self, arg, **kwargs): + I = S.ImaginaryUnit + from sympy.functions.elementary.hyperbolic import HyperbolicFunction + if isinstance(arg, (TrigonometricFunction, HyperbolicFunction)): + arg = arg.func(arg.args[0]).rewrite(exp, **kwargs) + return (exp(arg*I) + exp(-arg*I))/2 + + def _eval_rewrite_as_Pow(self, arg, **kwargs): + if isinstance(arg, log): + I = S.ImaginaryUnit + x = arg.args[0] + return x**I/2 + x**-I/2 + + def _eval_rewrite_as_sin(self, arg, **kwargs): + return sin(arg + pi/2, evaluate=False) + + def _eval_rewrite_as_tan(self, arg, **kwargs): + tan_half = tan(S.Half*arg)**2 + return (1 - tan_half)/(1 + tan_half) + + def _eval_rewrite_as_sincos(self, arg, **kwargs): + return sin(arg)*cos(arg)/sin(arg) + + def _eval_rewrite_as_cot(self, arg, **kwargs): + cot_half = cot(S.Half*arg)**2 + return Piecewise((1, And(Eq(im(arg), 0), Eq(Mod(arg, 2*pi), 0))), + ((cot_half - 1)/(cot_half + 1), True)) + + def _eval_rewrite_as_pow(self, arg, **kwargs): + return self._eval_rewrite_as_sqrt(arg, **kwargs) + + def _eval_rewrite_as_sqrt(self, arg: Expr, **kwargs): + from sympy.functions.special.polynomials import chebyshevt + + pi_coeff = _pi_coeff(arg) + if pi_coeff is None: + return None + + if isinstance(pi_coeff, Integer): + return None + + if not isinstance(pi_coeff, Rational): + return None + + cst_table_some = cos_table() + + if pi_coeff.q in cst_table_some: + rv = chebyshevt(pi_coeff.p, cst_table_some[pi_coeff.q]()) + if pi_coeff.q < 257: + rv = rv.expand() + return rv + + if not pi_coeff.q % 2: # recursively remove factors of 2 + pico2 = pi_coeff * 2 + nval = cos(pico2 * pi).rewrite(sqrt, **kwargs) + x = (pico2 + 1) / 2 + sign_cos = -1 if int(x) % 2 else 1 + return sign_cos * sqrt((1 + nval) / 2) + + FC = fermat_coords(pi_coeff.q) + if FC: + denoms = FC + else: + denoms = [b**e for b, e in factorint(pi_coeff.q).items()] + + apart = ipartfrac(*denoms) + decomp = (pi_coeff.p * Rational(n, d) for n, d in zip(apart, denoms)) + X = [(x[1], x[0]*pi) for x in zip(decomp, numbered_symbols('z'))] + pcls = cos(sum(x[0] for x in X))._eval_expand_trig().subs(X) + + if not FC or len(FC) == 1: + return pcls + return pcls.rewrite(sqrt, **kwargs) + + def _eval_rewrite_as_sec(self, arg, **kwargs): + return 1/sec(arg) + + def _eval_rewrite_as_csc(self, arg, **kwargs): + return 1/sec(arg).rewrite(csc, **kwargs) + + def _eval_rewrite_as_besselj(self, arg, **kwargs): + from sympy.functions.special.bessel import besselj + return Piecewise( + (sqrt(pi*arg/2)*besselj(-S.Half, arg), Ne(arg, 0)), + (1, True) + ) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def as_real_imag(self, deep=True, **hints): + from sympy.functions.elementary.hyperbolic import cosh, sinh + re, im = self._as_real_imag(deep=deep, **hints) + return (cos(re)*cosh(im), -sin(re)*sinh(im)) + + def _eval_expand_trig(self, **hints): + from sympy.functions.special.polynomials import chebyshevt + arg = self.args[0] + x = None + if arg.is_Add: # TODO: Do this more efficiently for more than two terms + x, y = arg.as_two_terms() + sx = sin(x, evaluate=False)._eval_expand_trig() + sy = sin(y, evaluate=False)._eval_expand_trig() + cx = cos(x, evaluate=False)._eval_expand_trig() + cy = cos(y, evaluate=False)._eval_expand_trig() + return cx*cy - sx*sy + elif arg.is_Mul: + coeff, terms = arg.as_coeff_Mul(rational=True) + if coeff.is_Integer: + return chebyshevt(coeff, cos(terms)) + return cos(arg) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.accumulationbounds import AccumBounds + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + n = (x0 + pi/2)/pi + if n.is_integer: + lt = (arg - n*pi + pi/2).as_leading_term(x) + return (S.NegativeOne**n)*lt + if x0 is S.ComplexInfinity: + x0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if x0 in [S.Infinity, S.NegativeInfinity]: + return AccumBounds(-1, 1) + return self.func(x0) if x0.is_finite else self + + def _eval_is_extended_real(self): + if self.args[0].is_extended_real: + return True + + def _eval_is_finite(self): + arg = self.args[0] + + if arg.is_extended_real: + return True + + def _eval_is_complex(self): + if self.args[0].is_extended_real \ + or self.args[0].is_complex: + return True + + def _eval_is_zero(self): + rest, pi_mult = _peeloff_pi(self.args[0]) + if rest.is_zero and pi_mult: + return (pi_mult - S.Half).is_integer + + +class tan(TrigonometricFunction): + """ + The tangent function. + + Returns the tangent of x (measured in radians). + + Explanation + =========== + + See :class:`sin` for notes about automatic evaluation. + + Examples + ======== + + >>> from sympy import tan, pi + >>> from sympy.abc import x + >>> tan(x**2).diff(x) + 2*x*(tan(x**2)**2 + 1) + >>> tan(1).diff(x) + 0 + >>> tan(pi/8).expand() + -1 + sqrt(2) + + See Also + ======== + + sin, csc, cos, sec, cot + asin, acsc, acos, asec, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_functions + .. [2] https://dlmf.nist.gov/4.14 + .. [3] https://functions.wolfram.com/ElementaryFunctions/Tan + + """ + + def period(self, symbol=None): + return self._period(pi, symbol) + + def fdiff(self, argindex=1): + if argindex == 1: + return S.One + self**2 + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return atan + + @classmethod + def eval(cls, arg): + from sympy.calculus.accumulationbounds import AccumBounds + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg.is_zero: + return S.Zero + elif arg in (S.Infinity, S.NegativeInfinity): + return AccumBounds(S.NegativeInfinity, S.Infinity) + + if arg is S.ComplexInfinity: + return S.NaN + + if isinstance(arg, AccumBounds): + min, max = arg.min, arg.max + d = floor(min/pi) + if min is not S.NegativeInfinity: + min = min - d*pi + if max is not S.Infinity: + max = max - d*pi + from sympy.sets.sets import FiniteSet + if AccumBounds(min, max).intersection(FiniteSet(pi/2, pi*Rational(3, 2))): + return AccumBounds(S.NegativeInfinity, S.Infinity) + else: + return AccumBounds(tan(min), tan(max)) + + if arg.could_extract_minus_sign(): + return -cls(-arg) + + i_coeff = _imaginary_unit_as_coefficient(arg) + if i_coeff is not None: + from sympy.functions.elementary.hyperbolic import tanh + return S.ImaginaryUnit*tanh(i_coeff) + + pi_coeff = _pi_coeff(arg, 2) + if pi_coeff is not None: + if pi_coeff.is_integer: + return S.Zero + + if not pi_coeff.is_Rational: + narg = pi_coeff*pi + if narg != arg: + return cls(narg) + return None + + if pi_coeff.is_Rational: + q = pi_coeff.q + p = pi_coeff.p % q + # ensure simplified results are returned for n*pi/5, n*pi/10 + table10 = { + 1: sqrt(1 - 2*sqrt(5)/5), + 2: sqrt(5 - 2*sqrt(5)), + 3: sqrt(1 + 2*sqrt(5)/5), + 4: sqrt(5 + 2*sqrt(5)) + } + if q in (5, 10): + n = 10*p/q + if n > 5: + n = 10 - n + return -table10[n] + else: + return table10[n] + if not pi_coeff.q % 2: + narg = pi_coeff*pi*2 + cresult, sresult = cos(narg), cos(narg - pi/2) + if not isinstance(cresult, cos) \ + and not isinstance(sresult, cos): + if sresult == 0: + return S.ComplexInfinity + return 1/sresult - cresult/sresult + + table2 = _table2() + if q in table2: + a, b = table2[q] + nvala, nvalb = cls(p*pi/a), cls(p*pi/b) + if None in (nvala, nvalb): + return None + return (nvala - nvalb)/(1 + nvala*nvalb) + narg = ((pi_coeff + S.Half) % 1 - S.Half)*pi + # see cos() to specify which expressions should be + # expanded automatically in terms of radicals + cresult, sresult = cos(narg), cos(narg - pi/2) + if not isinstance(cresult, cos) \ + and not isinstance(sresult, cos): + if cresult == 0: + return S.ComplexInfinity + return (sresult/cresult) + if narg != arg: + return cls(narg) + + if arg.is_Add: + x, m = _peeloff_pi(arg) + if m: + tanm = tan(m*pi) + if tanm is S.ComplexInfinity: + return -cot(x) + else: # tanm == 0 + return tan(x) + + if arg.is_zero: + return S.Zero + + if isinstance(arg, atan): + return arg.args[0] + + if isinstance(arg, atan2): + y, x = arg.args + return y/x + + if isinstance(arg, asin): + x = arg.args[0] + return x/sqrt(1 - x**2) + + if isinstance(arg, acos): + x = arg.args[0] + return sqrt(1 - x**2)/x + + if isinstance(arg, acot): + x = arg.args[0] + return 1/x + + if isinstance(arg, acsc): + x = arg.args[0] + return 1/(sqrt(1 - 1/x**2)*x) + + if isinstance(arg, asec): + x = arg.args[0] + return sqrt(1 - 1/x**2)*x + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + + a, b = ((n - 1)//2), 2**(n + 1) + + B = bernoulli(n + 1) + F = factorial(n + 1) + + return S.NegativeOne**a*b*(b - 1)*B/F*x**n + + def _eval_nseries(self, x, n, logx, cdir=0): + i = self.args[0].limit(x, 0)*2/pi + if i and i.is_Integer: + return self.rewrite(cos)._eval_nseries(x, n=n, logx=logx) + return super()._eval_nseries(x, n=n, logx=logx) + + def _eval_rewrite_as_Pow(self, arg, **kwargs): + if isinstance(arg, log): + I = S.ImaginaryUnit + x = arg.args[0] + return I*(x**-I - x**I)/(x**-I + x**I) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def as_real_imag(self, deep=True, **hints): + re, im = self._as_real_imag(deep=deep, **hints) + if im: + from sympy.functions.elementary.hyperbolic import cosh, sinh + denom = cos(2*re) + cosh(2*im) + return (sin(2*re)/denom, sinh(2*im)/denom) + else: + return (self.func(re), S.Zero) + + def _eval_expand_trig(self, **hints): + arg = self.args[0] + x = None + if arg.is_Add: + n = len(arg.args) + TX = [] + for x in arg.args: + tx = tan(x, evaluate=False)._eval_expand_trig() + TX.append(tx) + + Yg = numbered_symbols('Y') + Y = [ next(Yg) for i in range(n) ] + + p = [0, 0] + for i in range(n + 1): + p[1 - i % 2] += symmetric_poly(i, Y)*(-1)**((i % 4)//2) + return (p[0]/p[1]).subs(list(zip(Y, TX))) + + elif arg.is_Mul: + coeff, terms = arg.as_coeff_Mul(rational=True) + if coeff.is_Integer and coeff > 1: + I = S.ImaginaryUnit + z = Symbol('dummy', real=True) + P = ((1 + I*z)**coeff).expand() + return (im(P)/re(P)).subs([(z, tan(terms))]) + return tan(arg) + + def _eval_rewrite_as_exp(self, arg, **kwargs): + I = S.ImaginaryUnit + from sympy.functions.elementary.hyperbolic import HyperbolicFunction + if isinstance(arg, (TrigonometricFunction, HyperbolicFunction)): + arg = arg.func(arg.args[0]).rewrite(exp) + neg_exp, pos_exp = exp(-arg*I), exp(arg*I) + return I*(neg_exp - pos_exp)/(neg_exp + pos_exp) + + def _eval_rewrite_as_sin(self, x, **kwargs): + return 2*sin(x)**2/sin(2*x) + + def _eval_rewrite_as_cos(self, x, **kwargs): + return cos(x - pi/2, evaluate=False)/cos(x) + + def _eval_rewrite_as_sincos(self, arg, **kwargs): + return sin(arg)/cos(arg) + + def _eval_rewrite_as_cot(self, arg, **kwargs): + return 1/cot(arg) + + def _eval_rewrite_as_sec(self, arg, **kwargs): + sin_in_sec_form = sin(arg).rewrite(sec, **kwargs) + cos_in_sec_form = cos(arg).rewrite(sec, **kwargs) + return sin_in_sec_form/cos_in_sec_form + + def _eval_rewrite_as_csc(self, arg, **kwargs): + sin_in_csc_form = sin(arg).rewrite(csc, **kwargs) + cos_in_csc_form = cos(arg).rewrite(csc, **kwargs) + return sin_in_csc_form/cos_in_csc_form + + def _eval_rewrite_as_pow(self, arg, **kwargs): + y = self.rewrite(cos, **kwargs).rewrite(pow, **kwargs) + if y.has(cos): + return None + return y + + def _eval_rewrite_as_sqrt(self, arg, **kwargs): + y = self.rewrite(cos, **kwargs).rewrite(sqrt, **kwargs) + if y.has(cos): + return None + return y + + def _eval_rewrite_as_besselj(self, arg, **kwargs): + from sympy.functions.special.bessel import besselj + return besselj(S.Half, arg)/besselj(-S.Half, arg) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.accumulationbounds import AccumBounds + from sympy.functions.elementary.complexes import re + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + n = 2*x0/pi + if n.is_integer: + lt = (arg - n*pi/2).as_leading_term(x) + return lt if n.is_even else -1/lt + if x0 is S.ComplexInfinity: + x0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if x0 in (S.Infinity, S.NegativeInfinity): + return AccumBounds(S.NegativeInfinity, S.Infinity) + return self.func(x0) if x0.is_finite else self + + def _eval_is_extended_real(self): + # FIXME: currently tan(pi/2) return zoo + return self.args[0].is_extended_real + + def _eval_is_real(self): + arg = self.args[0] + if arg.is_real and (arg/pi - S.Half).is_integer is False: + return True + + def _eval_is_finite(self): + arg = self.args[0] + + if arg.is_real and (arg/pi - S.Half).is_integer is False: + return True + + if arg.is_imaginary: + return True + + def _eval_is_zero(self): + rest, pi_mult = _peeloff_pi(self.args[0]) + if rest.is_zero: + return pi_mult.is_integer + + def _eval_is_complex(self): + arg = self.args[0] + + if arg.is_real and (arg/pi - S.Half).is_integer is False: + return True + + +class cot(TrigonometricFunction): + """ + The cotangent function. + + Returns the cotangent of x (measured in radians). + + Explanation + =========== + + See :class:`sin` for notes about automatic evaluation. + + Examples + ======== + + >>> from sympy import cot, pi + >>> from sympy.abc import x + >>> cot(x**2).diff(x) + 2*x*(-cot(x**2)**2 - 1) + >>> cot(1).diff(x) + 0 + >>> cot(pi/12) + sqrt(3) + 2 + + See Also + ======== + + sin, csc, cos, sec, tan + asin, acsc, acos, asec, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_functions + .. [2] https://dlmf.nist.gov/4.14 + .. [3] https://functions.wolfram.com/ElementaryFunctions/Cot + + """ + + def period(self, symbol=None): + return self._period(pi, symbol) + + def fdiff(self, argindex=1): + if argindex == 1: + return S.NegativeOne - self**2 + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return acot + + @classmethod + def eval(cls, arg): + from sympy.calculus.accumulationbounds import AccumBounds + if arg.is_Number: + if arg is S.NaN: + return S.NaN + if arg.is_zero: + return S.ComplexInfinity + elif arg in (S.Infinity, S.NegativeInfinity): + return AccumBounds(S.NegativeInfinity, S.Infinity) + + if arg is S.ComplexInfinity: + return S.NaN + + if isinstance(arg, AccumBounds): + return -tan(arg + pi/2) + + if arg.could_extract_minus_sign(): + return -cls(-arg) + + i_coeff = _imaginary_unit_as_coefficient(arg) + if i_coeff is not None: + from sympy.functions.elementary.hyperbolic import coth + return -S.ImaginaryUnit*coth(i_coeff) + + pi_coeff = _pi_coeff(arg, 2) + if pi_coeff is not None: + if pi_coeff.is_integer: + return S.ComplexInfinity + + if not pi_coeff.is_Rational: + narg = pi_coeff*pi + if narg != arg: + return cls(narg) + return None + + if pi_coeff.is_Rational: + if pi_coeff.q in (5, 10): + return tan(pi/2 - arg) + if pi_coeff.q > 2 and not pi_coeff.q % 2: + narg = pi_coeff*pi*2 + cresult, sresult = cos(narg), cos(narg - pi/2) + if not isinstance(cresult, cos) \ + and not isinstance(sresult, cos): + return 1/sresult + cresult/sresult + q = pi_coeff.q + p = pi_coeff.p % q + table2 = _table2() + if q in table2: + a, b = table2[q] + nvala, nvalb = cls(p*pi/a), cls(p*pi/b) + if None in (nvala, nvalb): + return None + return (1 + nvala*nvalb)/(nvalb - nvala) + narg = (((pi_coeff + S.Half) % 1) - S.Half)*pi + # see cos() to specify which expressions should be + # expanded automatically in terms of radicals + cresult, sresult = cos(narg), cos(narg - pi/2) + if not isinstance(cresult, cos) \ + and not isinstance(sresult, cos): + if sresult == 0: + return S.ComplexInfinity + return cresult/sresult + if narg != arg: + return cls(narg) + + if arg.is_Add: + x, m = _peeloff_pi(arg) + if m: + cotm = cot(m*pi) + if cotm is S.ComplexInfinity: + return cot(x) + else: # cotm == 0 + return -tan(x) + + if arg.is_zero: + return S.ComplexInfinity + + if isinstance(arg, acot): + return arg.args[0] + + if isinstance(arg, atan): + x = arg.args[0] + return 1/x + + if isinstance(arg, atan2): + y, x = arg.args + return x/y + + if isinstance(arg, asin): + x = arg.args[0] + return sqrt(1 - x**2)/x + + if isinstance(arg, acos): + x = arg.args[0] + return x/sqrt(1 - x**2) + + if isinstance(arg, acsc): + x = arg.args[0] + return sqrt(1 - 1/x**2)*x + + if isinstance(arg, asec): + x = arg.args[0] + return 1/(sqrt(1 - 1/x**2)*x) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return 1/sympify(x) + elif n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + + B = bernoulli(n + 1) + F = factorial(n + 1) + + return S.NegativeOne**((n + 1)//2)*2**(n + 1)*B/F*x**n + + def _eval_nseries(self, x, n, logx, cdir=0): + i = self.args[0].limit(x, 0)/pi + if i and i.is_Integer: + return self.rewrite(cos)._eval_nseries(x, n=n, logx=logx) + return self.rewrite(tan)._eval_nseries(x, n=n, logx=logx) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def as_real_imag(self, deep=True, **hints): + re, im = self._as_real_imag(deep=deep, **hints) + if im: + from sympy.functions.elementary.hyperbolic import cosh, sinh + denom = cos(2*re) - cosh(2*im) + return (-sin(2*re)/denom, sinh(2*im)/denom) + else: + return (self.func(re), S.Zero) + + def _eval_rewrite_as_exp(self, arg, **kwargs): + from sympy.functions.elementary.hyperbolic import HyperbolicFunction + I = S.ImaginaryUnit + if isinstance(arg, (TrigonometricFunction, HyperbolicFunction)): + arg = arg.func(arg.args[0]).rewrite(exp, **kwargs) + neg_exp, pos_exp = exp(-arg*I), exp(arg*I) + return I*(pos_exp + neg_exp)/(pos_exp - neg_exp) + + def _eval_rewrite_as_Pow(self, arg, **kwargs): + if isinstance(arg, log): + I = S.ImaginaryUnit + x = arg.args[0] + return -I*(x**-I + x**I)/(x**-I - x**I) + + def _eval_rewrite_as_sin(self, x, **kwargs): + return sin(2*x)/(2*(sin(x)**2)) + + def _eval_rewrite_as_cos(self, x, **kwargs): + return cos(x)/cos(x - pi/2, evaluate=False) + + def _eval_rewrite_as_sincos(self, arg, **kwargs): + return cos(arg)/sin(arg) + + def _eval_rewrite_as_tan(self, arg, **kwargs): + return 1/tan(arg) + + def _eval_rewrite_as_sec(self, arg, **kwargs): + cos_in_sec_form = cos(arg).rewrite(sec, **kwargs) + sin_in_sec_form = sin(arg).rewrite(sec, **kwargs) + return cos_in_sec_form/sin_in_sec_form + + def _eval_rewrite_as_csc(self, arg, **kwargs): + cos_in_csc_form = cos(arg).rewrite(csc, **kwargs) + sin_in_csc_form = sin(arg).rewrite(csc, **kwargs) + return cos_in_csc_form/sin_in_csc_form + + def _eval_rewrite_as_pow(self, arg, **kwargs): + y = self.rewrite(cos, **kwargs).rewrite(pow, **kwargs) + if y.has(cos): + return None + return y + + def _eval_rewrite_as_sqrt(self, arg, **kwargs): + y = self.rewrite(cos, **kwargs).rewrite(sqrt, **kwargs) + if y.has(cos): + return None + return y + + def _eval_rewrite_as_besselj(self, arg, **kwargs): + from sympy.functions.special.bessel import besselj + return besselj(-S.Half, arg)/besselj(S.Half, arg) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.accumulationbounds import AccumBounds + from sympy.functions.elementary.complexes import re + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + n = 2*x0/pi + if n.is_integer: + lt = (arg - n*pi/2).as_leading_term(x) + return 1/lt if n.is_even else -lt + if x0 is S.ComplexInfinity: + x0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if x0 in (S.Infinity, S.NegativeInfinity): + return AccumBounds(S.NegativeInfinity, S.Infinity) + return self.func(x0) if x0.is_finite else self + + def _eval_is_extended_real(self): + return self.args[0].is_extended_real + + def _eval_expand_trig(self, **hints): + arg = self.args[0] + x = None + if arg.is_Add: + n = len(arg.args) + CX = [] + for x in arg.args: + cx = cot(x, evaluate=False)._eval_expand_trig() + CX.append(cx) + + Yg = numbered_symbols('Y') + Y = [ next(Yg) for i in range(n) ] + + p = [0, 0] + for i in range(n, -1, -1): + p[(n - i) % 2] += symmetric_poly(i, Y)*(-1)**(((n - i) % 4)//2) + return (p[0]/p[1]).subs(list(zip(Y, CX))) + elif arg.is_Mul: + coeff, terms = arg.as_coeff_Mul(rational=True) + if coeff.is_Integer and coeff > 1: + I = S.ImaginaryUnit + z = Symbol('dummy', real=True) + P = ((z + I)**coeff).expand() + return (re(P)/im(P)).subs([(z, cot(terms))]) + return cot(arg) # XXX sec and csc return 1/cos and 1/sin + + def _eval_is_finite(self): + arg = self.args[0] + if arg.is_real and (arg/pi).is_integer is False: + return True + if arg.is_imaginary: + return True + + def _eval_is_real(self): + arg = self.args[0] + if arg.is_real and (arg/pi).is_integer is False: + return True + + def _eval_is_complex(self): + arg = self.args[0] + if arg.is_real and (arg/pi).is_integer is False: + return True + + def _eval_is_zero(self): + rest, pimult = _peeloff_pi(self.args[0]) + if pimult and rest.is_zero: + return (pimult - S.Half).is_integer + + def _eval_subs(self, old, new): + arg = self.args[0] + argnew = arg.subs(old, new) + if arg != argnew and (argnew/pi).is_integer: + return S.ComplexInfinity + return cot(argnew) + + +class ReciprocalTrigonometricFunction(TrigonometricFunction): + """Base class for reciprocal functions of trigonometric functions. """ + + _reciprocal_of = None # mandatory, to be defined in subclass + _singularities = (S.ComplexInfinity,) + + # _is_even and _is_odd are used for correct evaluation of csc(-x), sec(-x) + # TODO refactor into TrigonometricFunction common parts of + # trigonometric functions eval() like even/odd, func(x+2*k*pi), etc. + + # optional, to be defined in subclasses: + _is_even: FuzzyBool = None + _is_odd: FuzzyBool = None + + @classmethod + def eval(cls, arg): + if arg.could_extract_minus_sign(): + if cls._is_even: + return cls(-arg) + if cls._is_odd: + return -cls(-arg) + + pi_coeff = _pi_coeff(arg) + if (pi_coeff is not None + and not (2*pi_coeff).is_integer + and pi_coeff.is_Rational): + q = pi_coeff.q + p = pi_coeff.p % (2*q) + if p > q: + narg = (pi_coeff - 1)*pi + return -cls(narg) + if 2*p > q: + narg = (1 - pi_coeff)*pi + if cls._is_odd: + return cls(narg) + elif cls._is_even: + return -cls(narg) + + if hasattr(arg, 'inverse') and arg.inverse() == cls: + return arg.args[0] + + t = cls._reciprocal_of.eval(arg) + if t is None: + return t + elif any(isinstance(i, cos) for i in (t, -t)): + return (1/t).rewrite(sec) + elif any(isinstance(i, sin) for i in (t, -t)): + return (1/t).rewrite(csc) + else: + return 1/t + + def _call_reciprocal(self, method_name, *args, **kwargs): + # Calls method_name on _reciprocal_of + o = self._reciprocal_of(self.args[0]) + return getattr(o, method_name)(*args, **kwargs) + + def _calculate_reciprocal(self, method_name, *args, **kwargs): + # If calling method_name on _reciprocal_of returns a value != None + # then return the reciprocal of that value + t = self._call_reciprocal(method_name, *args, **kwargs) + return 1/t if t is not None else t + + def _rewrite_reciprocal(self, method_name, arg): + # Special handling for rewrite functions. If reciprocal rewrite returns + # unmodified expression, then return None + t = self._call_reciprocal(method_name, arg) + if t is not None and t != self._reciprocal_of(arg): + return 1/t + + def _period(self, symbol): + f = expand_mul(self.args[0]) + return self._reciprocal_of(f).period(symbol) + + def fdiff(self, argindex=1): + return -self._calculate_reciprocal("fdiff", argindex)/self**2 + + def _eval_rewrite_as_exp(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_exp", arg) + + def _eval_rewrite_as_Pow(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_Pow", arg) + + def _eval_rewrite_as_sin(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_sin", arg) + + def _eval_rewrite_as_cos(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_cos", arg) + + def _eval_rewrite_as_tan(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_tan", arg) + + def _eval_rewrite_as_pow(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_pow", arg) + + def _eval_rewrite_as_sqrt(self, arg, **kwargs): + return self._rewrite_reciprocal("_eval_rewrite_as_sqrt", arg) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def as_real_imag(self, deep=True, **hints): + return (1/self._reciprocal_of(self.args[0])).as_real_imag(deep, + **hints) + + def _eval_expand_trig(self, **hints): + return self._calculate_reciprocal("_eval_expand_trig", **hints) + + def _eval_is_extended_real(self): + return self._reciprocal_of(self.args[0])._eval_is_extended_real() + + def _eval_as_leading_term(self, x, logx, cdir): + return (1/self._reciprocal_of(self.args[0]))._eval_as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_is_finite(self): + return (1/self._reciprocal_of(self.args[0])).is_finite + + def _eval_nseries(self, x, n, logx, cdir=0): + return (1/self._reciprocal_of(self.args[0]))._eval_nseries(x, n, logx) + + +class sec(ReciprocalTrigonometricFunction): + """ + The secant function. + + Returns the secant of x (measured in radians). + + Explanation + =========== + + See :class:`sin` for notes about automatic evaluation. + + Examples + ======== + + >>> from sympy import sec + >>> from sympy.abc import x + >>> sec(x**2).diff(x) + 2*x*tan(x**2)*sec(x**2) + >>> sec(1).diff(x) + 0 + + See Also + ======== + + sin, csc, cos, tan, cot + asin, acsc, acos, asec, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_functions + .. [2] https://dlmf.nist.gov/4.14 + .. [3] https://functions.wolfram.com/ElementaryFunctions/Sec + + """ + + _reciprocal_of = cos + _is_even = True + + def period(self, symbol=None): + return self._period(symbol) + + def _eval_rewrite_as_cot(self, arg, **kwargs): + cot_half_sq = cot(arg/2)**2 + return (cot_half_sq + 1)/(cot_half_sq - 1) + + def _eval_rewrite_as_cos(self, arg, **kwargs): + return (1/cos(arg)) + + def _eval_rewrite_as_sincos(self, arg, **kwargs): + return sin(arg)/(cos(arg)*sin(arg)) + + def _eval_rewrite_as_sin(self, arg, **kwargs): + return (1/cos(arg).rewrite(sin, **kwargs)) + + def _eval_rewrite_as_tan(self, arg, **kwargs): + return (1/cos(arg).rewrite(tan, **kwargs)) + + def _eval_rewrite_as_csc(self, arg, **kwargs): + return csc(pi/2 - arg, evaluate=False) + + def fdiff(self, argindex=1): + if argindex == 1: + return tan(self.args[0])*sec(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_besselj(self, arg, **kwargs): + from sympy.functions.special.bessel import besselj + return Piecewise( + (1/(sqrt(pi*arg)/(sqrt(2))*besselj(-S.Half, arg)), Ne(arg, 0)), + (1, True) + ) + + def _eval_is_complex(self): + arg = self.args[0] + + if arg.is_complex and (arg/pi - S.Half).is_integer is False: + return True + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + # Reference Formula: + # https://functions.wolfram.com/ElementaryFunctions/Sec/06/01/02/01/ + if n < 0 or n % 2 == 1: + return S.Zero + else: + x = sympify(x) + k = n//2 + return S.NegativeOne**k*euler(2*k)/factorial(2*k)*x**(2*k) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.accumulationbounds import AccumBounds + from sympy.functions.elementary.complexes import re + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + n = (x0 + pi/2)/pi + if n.is_integer: + lt = (arg - n*pi + pi/2).as_leading_term(x) + return (S.NegativeOne**n)/lt + if x0 is S.ComplexInfinity: + x0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if x0 in (S.Infinity, S.NegativeInfinity): + return AccumBounds(S.NegativeInfinity, S.Infinity) + return self.func(x0) if x0.is_finite else self + + +class csc(ReciprocalTrigonometricFunction): + """ + The cosecant function. + + Returns the cosecant of x (measured in radians). + + Explanation + =========== + + See :func:`sin` for notes about automatic evaluation. + + Examples + ======== + + >>> from sympy import csc + >>> from sympy.abc import x + >>> csc(x**2).diff(x) + -2*x*cot(x**2)*csc(x**2) + >>> csc(1).diff(x) + 0 + + See Also + ======== + + sin, cos, sec, tan, cot + asin, acsc, acos, asec, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_functions + .. [2] https://dlmf.nist.gov/4.14 + .. [3] https://functions.wolfram.com/ElementaryFunctions/Csc + + """ + + _reciprocal_of = sin + _is_odd = True + + def period(self, symbol=None): + return self._period(symbol) + + def _eval_rewrite_as_sin(self, arg, **kwargs): + return (1/sin(arg)) + + def _eval_rewrite_as_sincos(self, arg, **kwargs): + return cos(arg)/(sin(arg)*cos(arg)) + + def _eval_rewrite_as_cot(self, arg, **kwargs): + cot_half = cot(arg/2) + return (1 + cot_half**2)/(2*cot_half) + + def _eval_rewrite_as_cos(self, arg, **kwargs): + return 1/sin(arg).rewrite(cos, **kwargs) + + def _eval_rewrite_as_sec(self, arg, **kwargs): + return sec(pi/2 - arg, evaluate=False) + + def _eval_rewrite_as_tan(self, arg, **kwargs): + return (1/sin(arg).rewrite(tan, **kwargs)) + + def _eval_rewrite_as_besselj(self, arg, **kwargs): + from sympy.functions.special.bessel import besselj + return sqrt(2/pi)*(1/(sqrt(arg)*besselj(S.Half, arg))) + + def fdiff(self, argindex=1): + if argindex == 1: + return -cot(self.args[0])*csc(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_is_complex(self): + arg = self.args[0] + if arg.is_real and (arg/pi).is_integer is False: + return True + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return 1/sympify(x) + elif n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + k = n//2 + 1 + return (S.NegativeOne**(k - 1)*2*(2**(2*k - 1) - 1)* + bernoulli(2*k)*x**(2*k - 1)/factorial(2*k)) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.calculus.accumulationbounds import AccumBounds + from sympy.functions.elementary.complexes import re + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + n = x0/pi + if n.is_integer: + lt = (arg - n*pi).as_leading_term(x) + return (S.NegativeOne**n)/lt + if x0 is S.ComplexInfinity: + x0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if x0 in (S.Infinity, S.NegativeInfinity): + return AccumBounds(S.NegativeInfinity, S.Infinity) + return self.func(x0) if x0.is_finite else self + + +class sinc(DefinedFunction): + r""" + Represents an unnormalized sinc function: + + .. math:: + + \operatorname{sinc}(x) = + \begin{cases} + \frac{\sin x}{x} & \qquad x \neq 0 \\ + 1 & \qquad x = 0 + \end{cases} + + Examples + ======== + + >>> from sympy import sinc, oo, jn + >>> from sympy.abc import x + >>> sinc(x) + sinc(x) + + * Automated Evaluation + + >>> sinc(0) + 1 + >>> sinc(oo) + 0 + + * Differentiation + + >>> sinc(x).diff() + cos(x)/x - sin(x)/x**2 + + * Series Expansion + + >>> sinc(x).series() + 1 - x**2/6 + x**4/120 + O(x**6) + + * As zero'th order spherical Bessel Function + + >>> sinc(x).rewrite(jn) + jn(0, x) + + See also + ======== + + sin + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Sinc_function + + """ + _singularities = (S.ComplexInfinity,) + + def fdiff(self, argindex=1): + x = self.args[0] + if argindex == 1: + # We would like to return the Piecewise here, but Piecewise.diff + # currently can't handle removable singularities, meaning things + # like sinc(x).diff(x, 2) give the wrong answer at x = 0. See + # https://github.com/sympy/sympy/issues/11402. + # + # return Piecewise(((x*cos(x) - sin(x))/x**2, Ne(x, S.Zero)), (S.Zero, S.true)) + return cos(x)/x - sin(x)/x**2 + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + if arg.is_zero: + return S.One + if arg.is_Number: + if arg in [S.Infinity, S.NegativeInfinity]: + return S.Zero + elif arg is S.NaN: + return S.NaN + + if arg is S.ComplexInfinity: + return S.NaN + + if arg.could_extract_minus_sign(): + return cls(-arg) + + pi_coeff = _pi_coeff(arg) + if pi_coeff is not None: + if pi_coeff.is_integer: + if fuzzy_not(arg.is_zero): + return S.Zero + elif (2*pi_coeff).is_integer: + return S.NegativeOne**(pi_coeff - S.Half)/arg + + def _eval_nseries(self, x, n, logx, cdir=0): + x = self.args[0] + return (sin(x)/x)._eval_nseries(x, n, logx) + + def _eval_rewrite_as_jn(self, arg, **kwargs): + from sympy.functions.special.bessel import jn + return jn(0, arg) + + def _eval_rewrite_as_sin(self, arg, **kwargs): + return Piecewise((sin(arg)/arg, Ne(arg, S.Zero)), (S.One, S.true)) + + def _eval_is_zero(self): + if self.args[0].is_infinite: + return True + rest, pi_mult = _peeloff_pi(self.args[0]) + if rest.is_zero: + return fuzzy_and([pi_mult.is_integer, pi_mult.is_nonzero]) + if rest.is_Number and pi_mult.is_integer: + return False + + def _eval_is_real(self): + if self.args[0].is_extended_real or self.args[0].is_imaginary: + return True + + _eval_is_finite = _eval_is_real + + +############################################################################### +########################### TRIGONOMETRIC INVERSES ############################ +############################################################################### + + +class InverseTrigonometricFunction(DefinedFunction): + """Base class for inverse trigonometric functions.""" + _singularities: tuple[Expr, ...] = (S.One, S.NegativeOne, S.Zero, S.ComplexInfinity) + + @staticmethod + @cacheit + def _asin_table(): + # Only keys with could_extract_minus_sign() == False + # are actually needed. + return { + sqrt(3)/2: pi/3, + sqrt(2)/2: pi/4, + 1/sqrt(2): pi/4, + sqrt((5 - sqrt(5))/8): pi/5, + sqrt(2)*sqrt(5 - sqrt(5))/4: pi/5, + sqrt((5 + sqrt(5))/8): pi*Rational(2, 5), + sqrt(2)*sqrt(5 + sqrt(5))/4: pi*Rational(2, 5), + S.Half: pi/6, + sqrt(2 - sqrt(2))/2: pi/8, + sqrt(S.Half - sqrt(2)/4): pi/8, + sqrt(2 + sqrt(2))/2: pi*Rational(3, 8), + sqrt(S.Half + sqrt(2)/4): pi*Rational(3, 8), + (sqrt(5) - 1)/4: pi/10, + (1 - sqrt(5))/4: -pi/10, + (sqrt(5) + 1)/4: pi*Rational(3, 10), + sqrt(6)/4 - sqrt(2)/4: pi/12, + -sqrt(6)/4 + sqrt(2)/4: -pi/12, + (sqrt(3) - 1)/sqrt(8): pi/12, + (1 - sqrt(3))/sqrt(8): -pi/12, + sqrt(6)/4 + sqrt(2)/4: pi*Rational(5, 12), + (1 + sqrt(3))/sqrt(8): pi*Rational(5, 12) + } + + + @staticmethod + @cacheit + def _atan_table(): + # Only keys with could_extract_minus_sign() == False + # are actually needed. + return { + sqrt(3)/3: pi/6, + 1/sqrt(3): pi/6, + sqrt(3): pi/3, + sqrt(2) - 1: pi/8, + 1 - sqrt(2): -pi/8, + 1 + sqrt(2): pi*Rational(3, 8), + sqrt(5 - 2*sqrt(5)): pi/5, + sqrt(5 + 2*sqrt(5)): pi*Rational(2, 5), + sqrt(1 - 2*sqrt(5)/5): pi/10, + sqrt(1 + 2*sqrt(5)/5): pi*Rational(3, 10), + 2 - sqrt(3): pi/12, + -2 + sqrt(3): -pi/12, + 2 + sqrt(3): pi*Rational(5, 12) + } + + @staticmethod + @cacheit + def _acsc_table(): + # Keys for which could_extract_minus_sign() + # will obviously return True are omitted. + return { + 2*sqrt(3)/3: pi/3, + sqrt(2): pi/4, + sqrt(2 + 2*sqrt(5)/5): pi/5, + 1/sqrt(Rational(5, 8) - sqrt(5)/8): pi/5, + sqrt(2 - 2*sqrt(5)/5): pi*Rational(2, 5), + 1/sqrt(Rational(5, 8) + sqrt(5)/8): pi*Rational(2, 5), + 2: pi/6, + sqrt(4 + 2*sqrt(2)): pi/8, + 2/sqrt(2 - sqrt(2)): pi/8, + sqrt(4 - 2*sqrt(2)): pi*Rational(3, 8), + 2/sqrt(2 + sqrt(2)): pi*Rational(3, 8), + 1 + sqrt(5): pi/10, + sqrt(5) - 1: pi*Rational(3, 10), + -(sqrt(5) - 1): pi*Rational(-3, 10), + sqrt(6) + sqrt(2): pi/12, + sqrt(6) - sqrt(2): pi*Rational(5, 12), + -(sqrt(6) - sqrt(2)): pi*Rational(-5, 12) + } + + +class asin(InverseTrigonometricFunction): + r""" + The inverse sine function. + + Returns the arcsine of x in radians. + + Explanation + =========== + + ``asin(x)`` will evaluate automatically in the cases + $x \in \{\infty, -\infty, 0, 1, -1\}$ and for some instances when the + result is a rational multiple of $\pi$ (see the ``eval`` class method). + + A purely imaginary argument will lead to an asinh expression. + + Examples + ======== + + >>> from sympy import asin, oo + >>> asin(1) + pi/2 + >>> asin(-1) + -pi/2 + >>> asin(-oo) + oo*I + >>> asin(oo) + -oo*I + + See Also + ======== + + sin, csc, cos, sec, tan, cot + acsc, acos, asec, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Inverse_trigonometric_functions + .. [2] https://dlmf.nist.gov/4.23 + .. [3] https://functions.wolfram.com/ElementaryFunctions/ArcSin + + """ + + def fdiff(self, argindex=1): + if argindex == 1: + return 1/sqrt(1 - self.args[0]**2) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_is_rational(self): + s = self.func(*self.args) + if s.func == self.func: + if s.args[0].is_rational: + return False + else: + return s.is_rational + + def _eval_is_positive(self): + return self._eval_is_extended_real() and self.args[0].is_positive + + def _eval_is_negative(self): + return self._eval_is_extended_real() and self.args[0].is_negative + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.NegativeInfinity*S.ImaginaryUnit + elif arg is S.NegativeInfinity: + return S.Infinity*S.ImaginaryUnit + elif arg.is_zero: + return S.Zero + elif arg is S.One: + return pi/2 + elif arg is S.NegativeOne: + return -pi/2 + + if arg is S.ComplexInfinity: + return S.ComplexInfinity + + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if arg.is_number: + asin_table = cls._asin_table() + if arg in asin_table: + return asin_table[arg] + + i_coeff = _imaginary_unit_as_coefficient(arg) + if i_coeff is not None: + from sympy.functions.elementary.hyperbolic import asinh + return S.ImaginaryUnit*asinh(i_coeff) + + if arg.is_zero: + return S.Zero + + if isinstance(arg, sin): + ang = arg.args[0] + if ang.is_comparable: + ang %= 2*pi # restrict to [0,2*pi) + if ang > pi: # restrict to (-pi,pi] + ang = pi - ang + + # restrict to [-pi/2,pi/2] + if ang > pi/2: + ang = pi - ang + if ang < -pi/2: + ang = -pi - ang + + return ang + + if isinstance(arg, cos): # acos(x) + asin(x) = pi/2 + ang = arg.args[0] + if ang.is_comparable: + return pi/2 - acos(arg) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) >= 2 and n > 2: + p = previous_terms[-2] + return p*(n - 2)**2/(n*(n - 1))*x**2 + else: + k = (n - 1) // 2 + R = RisingFactorial(S.Half, k) + F = factorial(k) + return R/F*x**n/n + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + if x0 is S.NaN: + return self.func(arg.as_leading_term(x)) + if x0.is_zero: + return arg.as_leading_term(x) + + # Handling branch points + if x0 in (-S.One, S.One, S.ComplexInfinity): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + # Handling points lying on branch cuts (-oo, -1) U (1, oo) + if (1 - x0**2).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if x0.is_negative: + return -pi - self.func(x0) + elif im(ndir).is_positive: + if x0.is_positive: + return pi - self.func(x0) + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # asin + from sympy.series.order import O + arg0 = self.args[0].subs(x, 0) + # Handling branch points + if arg0 is S.One: + t = Dummy('t', positive=True) + ser = asin(S.One - t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.One - self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + if not g.is_meromorphic(x, 0): # cannot be expanded + return O(1) if n == 0 else pi/2 + O(sqrt(x)) + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + if arg0 is S.NegativeOne: + t = Dummy('t', positive=True) + ser = asin(S.NegativeOne + t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.One + self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + if not g.is_meromorphic(x, 0): # cannot be expanded + return O(1) if n == 0 else -pi/2 + O(sqrt(x)) + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + # Handling points lying on branch cuts (-oo, -1) U (1, oo) + if (1 - arg0**2).is_negative: + ndir = self.args[0].dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if arg0.is_negative: + return -pi - res + elif im(ndir).is_positive: + if arg0.is_positive: + return pi - res + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_rewrite_as_acos(self, x, **kwargs): + return pi/2 - acos(x) + + def _eval_rewrite_as_atan(self, x, **kwargs): + return 2*atan(x/(1 + sqrt(1 - x**2))) + + def _eval_rewrite_as_log(self, x, **kwargs): + return -S.ImaginaryUnit*log(S.ImaginaryUnit*x + sqrt(1 - x**2)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_acot(self, arg, **kwargs): + return 2*acot((1 + sqrt(1 - arg**2))/arg) + + def _eval_rewrite_as_asec(self, arg, **kwargs): + return pi/2 - asec(1/arg) + + def _eval_rewrite_as_acsc(self, arg, **kwargs): + return acsc(1/arg) + + def _eval_is_extended_real(self): + x = self.args[0] + return x.is_extended_real and (1 - abs(x)).is_nonnegative + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return sin + + +class acos(InverseTrigonometricFunction): + r""" + The inverse cosine function. + + Explanation + =========== + + Returns the arc cosine of x (measured in radians). + + ``acos(x)`` will evaluate automatically in the cases + $x \in \{\infty, -\infty, 0, 1, -1\}$ and for some instances when + the result is a rational multiple of $\pi$ (see the eval class method). + + ``acos(zoo)`` evaluates to ``zoo`` + (see note in :class:`sympy.functions.elementary.trigonometric.asec`) + + A purely imaginary argument will be rewritten to asinh. + + Examples + ======== + + >>> from sympy import acos, oo + >>> acos(1) + 0 + >>> acos(0) + pi/2 + >>> acos(oo) + oo*I + + See Also + ======== + + sin, csc, cos, sec, tan, cot + asin, acsc, asec, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Inverse_trigonometric_functions + .. [2] https://dlmf.nist.gov/4.23 + .. [3] https://functions.wolfram.com/ElementaryFunctions/ArcCos + + """ + + def fdiff(self, argindex=1): + if argindex == 1: + return -1/sqrt(1 - self.args[0]**2) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_is_rational(self): + s = self.func(*self.args) + if s.func == self.func: + if s.args[0].is_rational: + return False + else: + return s.is_rational + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Infinity*S.ImaginaryUnit + elif arg is S.NegativeInfinity: + return S.NegativeInfinity*S.ImaginaryUnit + elif arg.is_zero: + return pi/2 + elif arg is S.One: + return S.Zero + elif arg is S.NegativeOne: + return pi + + if arg is S.ComplexInfinity: + return S.ComplexInfinity + + if arg.is_number: + asin_table = cls._asin_table() + if arg in asin_table: + return pi/2 - asin_table[arg] + elif -arg in asin_table: + return pi/2 + asin_table[-arg] + + i_coeff = _imaginary_unit_as_coefficient(arg) + if i_coeff is not None: + return pi/2 - asin(arg) + + if arg.is_Mul and len(arg.args) == 2 and arg.args[0] == -1: + narg = arg.args[1] + minus = True + else: + narg = arg + minus = False + + if isinstance(narg, cos): + # acos(cos(x)) = x or acos(-cos(x)) = pi - x + ang = narg.args[0] + if ang.is_comparable: + if minus: + ang = pi - ang + ang %= 2*pi # restrict to [0,2*pi) + if ang > pi: # restrict to [0,pi] + ang = 2*pi - ang + return ang + + if isinstance(narg, sin): # acos(x) + asin(x) = pi/2 + ang = narg.args[0] + if ang.is_comparable: + if minus: + return pi/2 + asin(narg) + return pi/2 - asin(narg) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return pi/2 + elif n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) >= 2 and n > 2: + p = previous_terms[-2] + return p*(n - 2)**2/(n*(n - 1))*x**2 + else: + k = (n - 1) // 2 + R = RisingFactorial(S.Half, k) + F = factorial(k) + return -R/F*x**n/n + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + if x0 is S.NaN: + return self.func(arg.as_leading_term(x)) + # Handling branch points + if x0 == 1: + return sqrt(2)*sqrt((S.One - arg).as_leading_term(x)) + if x0 in (-S.One, S.ComplexInfinity): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + # Handling points lying on branch cuts (-oo, -1) U (1, oo) + if (1 - x0**2).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if x0.is_negative: + return 2*pi - self.func(x0) + elif im(ndir).is_positive: + if x0.is_positive: + return -self.func(x0) + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + return self.func(x0) + + def _eval_is_extended_real(self): + x = self.args[0] + return x.is_extended_real and (1 - abs(x)).is_nonnegative + + def _eval_is_nonnegative(self): + return self._eval_is_extended_real() + + def _eval_nseries(self, x, n, logx, cdir=0): # acos + from sympy.series.order import O + arg0 = self.args[0].subs(x, 0) + # Handling branch points + if arg0 is S.One: + t = Dummy('t', positive=True) + ser = acos(S.One - t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.One - self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + if not g.is_meromorphic(x, 0): # cannot be expanded + return O(1) if n == 0 else O(sqrt(x)) + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + if arg0 is S.NegativeOne: + t = Dummy('t', positive=True) + ser = acos(S.NegativeOne + t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.One + self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + if not g.is_meromorphic(x, 0): # cannot be expanded + return O(1) if n == 0 else pi + O(sqrt(x)) + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + # Handling points lying on branch cuts (-oo, -1) U (1, oo) + if (1 - arg0**2).is_negative: + ndir = self.args[0].dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if arg0.is_negative: + return 2*pi - res + elif im(ndir).is_positive: + if arg0.is_positive: + return -res + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_rewrite_as_log(self, x, **kwargs): + return pi/2 + S.ImaginaryUnit*\ + log(S.ImaginaryUnit*x + sqrt(1 - x**2)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_asin(self, x, **kwargs): + return pi/2 - asin(x) + + def _eval_rewrite_as_atan(self, x, **kwargs): + return atan(sqrt(1 - x**2)/x) + (pi/2)*(1 - x*sqrt(1/x**2)) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return cos + + def _eval_rewrite_as_acot(self, arg, **kwargs): + return pi/2 - 2*acot((1 + sqrt(1 - arg**2))/arg) + + def _eval_rewrite_as_asec(self, arg, **kwargs): + return asec(1/arg) + + def _eval_rewrite_as_acsc(self, arg, **kwargs): + return pi/2 - acsc(1/arg) + + def _eval_conjugate(self): + z = self.args[0] + r = self.func(self.args[0].conjugate()) + if z.is_extended_real is False: + return r + elif z.is_extended_real and (z + 1).is_nonnegative and (z - 1).is_nonpositive: + return r + + +class atan(InverseTrigonometricFunction): + r""" + The inverse tangent function. + + Returns the arc tangent of x (measured in radians). + + Explanation + =========== + + ``atan(x)`` will evaluate automatically in the cases + $x \in \{\infty, -\infty, 0, 1, -1\}$ and for some instances when the + result is a rational multiple of $\pi$ (see the eval class method). + + Examples + ======== + + >>> from sympy import atan, oo + >>> atan(0) + 0 + >>> atan(1) + pi/4 + >>> atan(oo) + pi/2 + + See Also + ======== + + sin, csc, cos, sec, tan, cot + asin, acsc, acos, asec, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Inverse_trigonometric_functions + .. [2] https://dlmf.nist.gov/4.23 + .. [3] https://functions.wolfram.com/ElementaryFunctions/ArcTan + + """ + + args: tuple[Expr] + + _singularities = (S.ImaginaryUnit, -S.ImaginaryUnit) + + def fdiff(self, argindex=1): + if argindex == 1: + return 1/(1 + self.args[0]**2) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_is_rational(self): + s = self.func(*self.args) + if s.func == self.func: + if s.args[0].is_rational: + return False + else: + return s.is_rational + + def _eval_is_positive(self): + return self.args[0].is_extended_positive + + def _eval_is_nonnegative(self): + return self.args[0].is_extended_nonnegative + + def _eval_is_zero(self): + return self.args[0].is_zero + + def _eval_is_real(self): + return self.args[0].is_extended_real + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return pi/2 + elif arg is S.NegativeInfinity: + return -pi/2 + elif arg.is_zero: + return S.Zero + elif arg is S.One: + return pi/4 + elif arg is S.NegativeOne: + return -pi/4 + + if arg is S.ComplexInfinity: + from sympy.calculus.accumulationbounds import AccumBounds + return AccumBounds(-pi/2, pi/2) + + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if arg.is_number: + atan_table = cls._atan_table() + if arg in atan_table: + return atan_table[arg] + + i_coeff = _imaginary_unit_as_coefficient(arg) + if i_coeff is not None: + from sympy.functions.elementary.hyperbolic import atanh + return S.ImaginaryUnit*atanh(i_coeff) + + if arg.is_zero: + return S.Zero + + if isinstance(arg, tan): + ang = arg.args[0] + if ang.is_comparable: + ang %= pi # restrict to [0,pi) + if ang > pi/2: # restrict to [-pi/2,pi/2] + ang -= pi + + return ang + + if isinstance(arg, cot): # atan(x) + acot(x) = pi/2 + ang = arg.args[0] + if ang.is_comparable: + ang = pi/2 - acot(arg) + if ang > pi/2: # restrict to [-pi/2,pi/2] + ang -= pi + return ang + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + return S.NegativeOne**((n - 1)//2)*x**n/n + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + if x0 is S.NaN: + return self.func(arg.as_leading_term(x)) + if x0.is_zero: + return arg.as_leading_term(x) + # Handling branch points + if x0 in (-S.ImaginaryUnit, S.ImaginaryUnit, S.ComplexInfinity): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + # Handling points lying on branch cuts (-I*oo, -I) U (I, I*oo) + if (1 + x0**2).is_negative: + ndir = arg.dir(x, cdir if cdir else 1) + if re(ndir).is_negative: + if im(x0).is_positive: + return self.func(x0) - pi + elif re(ndir).is_positive: + if im(x0).is_negative: + return self.func(x0) + pi + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # atan + arg0 = self.args[0].subs(x, 0) + + # Handling branch points + if arg0 in (S.ImaginaryUnit, S.NegativeOne*S.ImaginaryUnit): + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + + res = super()._eval_nseries(x, n=n, logx=logx) + ndir = self.args[0].dir(x, cdir if cdir else 1) + if arg0 is S.ComplexInfinity: + if re(ndir) > 0: + return res - pi + return res + # Handling points lying on branch cuts (-I*oo, -I) U (I, I*oo) + if (1 + arg0**2).is_negative: + if re(ndir).is_negative: + if im(arg0).is_positive: + return res - pi + elif re(ndir).is_positive: + if im(arg0).is_negative: + return res + pi + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_rewrite_as_log(self, x, **kwargs): + return S.ImaginaryUnit/2*(log(S.One - S.ImaginaryUnit*x) + - log(S.One + S.ImaginaryUnit*x)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_aseries(self, n, args0, x, logx): + if args0[0] in [S.Infinity, S.NegativeInfinity]: + return (pi/2 - atan(1/self.args[0]))._eval_nseries(x, n, logx) + else: + return super()._eval_aseries(n, args0, x, logx) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return tan + + def _eval_rewrite_as_asin(self, arg, **kwargs): + return sqrt(arg**2)/arg*(pi/2 - asin(1/sqrt(1 + arg**2))) + + def _eval_rewrite_as_acos(self, arg, **kwargs): + return sqrt(arg**2)/arg*acos(1/sqrt(1 + arg**2)) + + def _eval_rewrite_as_acot(self, arg, **kwargs): + return acot(1/arg) + + def _eval_rewrite_as_asec(self, arg, **kwargs): + return sqrt(arg**2)/arg*asec(sqrt(1 + arg**2)) + + def _eval_rewrite_as_acsc(self, arg, **kwargs): + return sqrt(arg**2)/arg*(pi/2 - acsc(sqrt(1 + arg**2))) + + +class acot(InverseTrigonometricFunction): + r""" + The inverse cotangent function. + + Returns the arc cotangent of x (measured in radians). + + Explanation + =========== + + ``acot(x)`` will evaluate automatically in the cases + $x \in \{\infty, -\infty, \tilde{\infty}, 0, 1, -1\}$ + and for some instances when the result is a rational multiple of $\pi$ + (see the eval class method). + + A purely imaginary argument will lead to an ``acoth`` expression. + + ``acot(x)`` has a branch cut along $(-i, i)$, hence it is discontinuous + at 0. Its range for real $x$ is $(-\frac{\pi}{2}, \frac{\pi}{2}]$. + + Examples + ======== + + >>> from sympy import acot, sqrt + >>> acot(0) + pi/2 + >>> acot(1) + pi/4 + >>> acot(sqrt(3) - 2) + -5*pi/12 + + See Also + ======== + + sin, csc, cos, sec, tan, cot + asin, acsc, acos, asec, atan, atan2 + + References + ========== + + .. [1] https://dlmf.nist.gov/4.23 + .. [2] https://functions.wolfram.com/ElementaryFunctions/ArcCot + + """ + _singularities = (S.ImaginaryUnit, -S.ImaginaryUnit) + + def fdiff(self, argindex=1): + if argindex == 1: + return -1/(1 + self.args[0]**2) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_is_rational(self): + s = self.func(*self.args) + if s.func == self.func: + if s.args[0].is_rational: + return False + else: + return s.is_rational + + def _eval_is_positive(self): + return self.args[0].is_nonnegative + + def _eval_is_negative(self): + return self.args[0].is_negative + + def _eval_is_extended_real(self): + return self.args[0].is_extended_real + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Zero + elif arg is S.NegativeInfinity: + return S.Zero + elif arg.is_zero: + return pi/ 2 + elif arg is S.One: + return pi/4 + elif arg is S.NegativeOne: + return -pi/4 + + if arg is S.ComplexInfinity: + return S.Zero + + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if arg.is_number: + atan_table = cls._atan_table() + if arg in atan_table: + ang = pi/2 - atan_table[arg] + if ang > pi/2: # restrict to (-pi/2,pi/2] + ang -= pi + return ang + + i_coeff = _imaginary_unit_as_coefficient(arg) + if i_coeff is not None: + from sympy.functions.elementary.hyperbolic import acoth + return -S.ImaginaryUnit*acoth(i_coeff) + + if arg.is_zero: + return pi*S.Half + + if isinstance(arg, cot): + ang = arg.args[0] + if ang.is_comparable: + ang %= pi # restrict to [0,pi) + if ang > pi/2: # restrict to (-pi/2,pi/2] + ang -= pi + return ang + + if isinstance(arg, tan): # atan(x) + acot(x) = pi/2 + ang = arg.args[0] + if ang.is_comparable: + ang = pi/2 - atan(arg) + if ang > pi/2: # restrict to (-pi/2,pi/2] + ang -= pi + return ang + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return pi/2 # FIX THIS + elif n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + return S.NegativeOne**((n + 1)//2)*x**n/n + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + if x0 is S.NaN: + return self.func(arg.as_leading_term(x)) + if x0 is S.ComplexInfinity: + return (1/arg).as_leading_term(x) + # Handling branch points + if x0 in (-S.ImaginaryUnit, S.ImaginaryUnit, S.Zero): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + # Handling points lying on branch cuts [-I, I] + if x0.is_imaginary and (1 + x0**2).is_positive: + ndir = arg.dir(x, cdir if cdir else 1) + if re(ndir).is_positive: + if im(x0).is_positive: + return self.func(x0) + pi + elif re(ndir).is_negative: + if im(x0).is_negative: + return self.func(x0) - pi + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # acot + arg0 = self.args[0].subs(x, 0) + + # Handling branch points + if arg0 in (S.ImaginaryUnit, S.NegativeOne*S.ImaginaryUnit): + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + ndir = self.args[0].dir(x, cdir if cdir else 1) + if arg0.is_zero: + if re(ndir) < 0: + return res - pi + return res + # Handling points lying on branch cuts [-I, I] + if arg0.is_imaginary and (1 + arg0**2).is_positive: + if re(ndir).is_positive: + if im(arg0).is_positive: + return res + pi + elif re(ndir).is_negative: + if im(arg0).is_negative: + return res - pi + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_aseries(self, n, args0, x, logx): + if args0[0] in [S.Infinity, S.NegativeInfinity]: + return atan(1/self.args[0])._eval_nseries(x, n, logx) + else: + return super()._eval_aseries(n, args0, x, logx) + + def _eval_rewrite_as_log(self, x, **kwargs): + return S.ImaginaryUnit/2*(log(1 - S.ImaginaryUnit/x) + - log(1 + S.ImaginaryUnit/x)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return cot + + def _eval_rewrite_as_asin(self, arg, **kwargs): + return (arg*sqrt(1/arg**2)* + (pi/2 - asin(sqrt(-arg**2)/sqrt(-arg**2 - 1)))) + + def _eval_rewrite_as_acos(self, arg, **kwargs): + return arg*sqrt(1/arg**2)*acos(sqrt(-arg**2)/sqrt(-arg**2 - 1)) + + def _eval_rewrite_as_atan(self, arg, **kwargs): + return atan(1/arg) + + def _eval_rewrite_as_asec(self, arg, **kwargs): + return arg*sqrt(1/arg**2)*asec(sqrt((1 + arg**2)/arg**2)) + + def _eval_rewrite_as_acsc(self, arg, **kwargs): + return arg*sqrt(1/arg**2)*(pi/2 - acsc(sqrt((1 + arg**2)/arg**2))) + + +class asec(InverseTrigonometricFunction): + r""" + The inverse secant function. + + Returns the arc secant of x (measured in radians). + + Explanation + =========== + + ``asec(x)`` will evaluate automatically in the cases + $x \in \{\infty, -\infty, 0, 1, -1\}$ and for some instances when the + result is a rational multiple of $\pi$ (see the eval class method). + + ``asec(x)`` has branch cut in the interval $[-1, 1]$. For complex arguments, + it can be defined [4]_ as + + .. math:: + \operatorname{sec^{-1}}(z) = -i\frac{\log\left(\sqrt{1 - z^2} + 1\right)}{z} + + At ``x = 0``, for positive branch cut, the limit evaluates to ``zoo``. For + negative branch cut, the limit + + .. math:: + \lim_{z \to 0}-i\frac{\log\left(-\sqrt{1 - z^2} + 1\right)}{z} + + simplifies to :math:`-i\log\left(z/2 + O\left(z^3\right)\right)` which + ultimately evaluates to ``zoo``. + + As ``acos(x) = asec(1/x)``, a similar argument can be given for + ``acos(x)``. + + Examples + ======== + + >>> from sympy import asec, oo + >>> asec(1) + 0 + >>> asec(-1) + pi + >>> asec(0) + zoo + >>> asec(-oo) + pi/2 + + See Also + ======== + + sin, csc, cos, sec, tan, cot + asin, acsc, acos, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Inverse_trigonometric_functions + .. [2] https://dlmf.nist.gov/4.23 + .. [3] https://functions.wolfram.com/ElementaryFunctions/ArcSec + .. [4] https://reference.wolfram.com/language/ref/ArcSec.html + + """ + + @classmethod + def eval(cls, arg): + if arg.is_zero: + return S.ComplexInfinity + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.One: + return S.Zero + elif arg is S.NegativeOne: + return pi + if arg in [S.Infinity, S.NegativeInfinity, S.ComplexInfinity]: + return pi/2 + + if arg.is_number: + acsc_table = cls._acsc_table() + if arg in acsc_table: + return pi/2 - acsc_table[arg] + elif -arg in acsc_table: + return pi/2 + acsc_table[-arg] + + if arg.is_infinite: + return pi/2 + + if arg.is_Mul and len(arg.args) == 2 and arg.args[0] == -1: + narg = arg.args[1] + minus = True + else: + narg = arg + minus = False + + if isinstance(narg, sec): + # asec(sec(x)) = x or asec(-sec(x)) = pi - x + ang = narg.args[0] + if ang.is_comparable: + if minus: + ang = pi - ang + ang %= 2*pi # restrict to [0,2*pi) + if ang > pi: # restrict to [0,pi] + ang = 2*pi - ang + return ang + + if isinstance(narg, csc): # asec(x) + acsc(x) = pi/2 + ang = narg.args[0] + if ang.is_comparable: + if minus: + pi/2 + acsc(narg) + return pi/2 - acsc(narg) + + def fdiff(self, argindex=1): + if argindex == 1: + return 1/(self.args[0]**2*sqrt(1 - 1/self.args[0]**2)) + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return sec + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return S.ImaginaryUnit*log(2 / x) + elif n < 0 or n % 2 == 1: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) > 2 and n > 2: + p = previous_terms[-2] + return p * ((n - 1)*(n-2)) * x**2/(4 * (n//2)**2) + else: + k = n // 2 + R = RisingFactorial(S.Half, k) * n + F = factorial(k) * n // 2 * n // 2 + return -S.ImaginaryUnit * R / F * x**n / 4 + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + if x0 is S.NaN: + return self.func(arg.as_leading_term(x)) + # Handling branch points + if x0 == 1: + return sqrt(2)*sqrt((arg - S.One).as_leading_term(x)) + if x0 in (-S.One, S.Zero): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir) + # Handling points lying on branch cuts (-1, 1) + if x0.is_real and (1 - x0**2).is_positive: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if x0.is_positive: + return -self.func(x0) + elif im(ndir).is_positive: + if x0.is_negative: + return 2*pi - self.func(x0) + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # asec + from sympy.series.order import O + arg0 = self.args[0].subs(x, 0) + # Handling branch points + if arg0 is S.One: + t = Dummy('t', positive=True) + ser = asec(S.One + t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.NegativeOne + self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + if arg0 is S.NegativeOne: + t = Dummy('t', positive=True) + ser = asec(S.NegativeOne - t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.NegativeOne - self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + # Handling points lying on branch cuts (-1, 1) + if arg0.is_real and (1 - arg0**2).is_positive: + ndir = self.args[0].dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if arg0.is_positive: + return -res + elif im(ndir).is_positive: + if arg0.is_negative: + return 2*pi - res + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_is_extended_real(self): + x = self.args[0] + if x.is_extended_real is False: + return False + return fuzzy_or(((x - 1).is_nonnegative, (-x - 1).is_nonnegative)) + + def _eval_rewrite_as_log(self, arg, **kwargs): + return pi/2 + S.ImaginaryUnit*log(S.ImaginaryUnit/arg + sqrt(1 - 1/arg**2)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_asin(self, arg, **kwargs): + return pi/2 - asin(1/arg) + + def _eval_rewrite_as_acos(self, arg, **kwargs): + return acos(1/arg) + + def _eval_rewrite_as_atan(self, x, **kwargs): + sx2x = sqrt(x**2)/x + return pi/2*(1 - sx2x) + sx2x*atan(sqrt(x**2 - 1)) + + def _eval_rewrite_as_acot(self, x, **kwargs): + sx2x = sqrt(x**2)/x + return pi/2*(1 - sx2x) + sx2x*acot(1/sqrt(x**2 - 1)) + + def _eval_rewrite_as_acsc(self, arg, **kwargs): + return pi/2 - acsc(arg) + + +class acsc(InverseTrigonometricFunction): + r""" + The inverse cosecant function. + + Returns the arc cosecant of x (measured in radians). + + Explanation + =========== + + ``acsc(x)`` will evaluate automatically in the cases + $x \in \{\infty, -\infty, 0, 1, -1\}$` and for some instances when the + result is a rational multiple of $\pi$ (see the ``eval`` class method). + + Examples + ======== + + >>> from sympy import acsc, oo + >>> acsc(1) + pi/2 + >>> acsc(-1) + -pi/2 + >>> acsc(oo) + 0 + >>> acsc(-oo) == acsc(oo) + True + >>> acsc(0) + zoo + + See Also + ======== + + sin, csc, cos, sec, tan, cot + asin, acos, asec, atan, acot, atan2 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Inverse_trigonometric_functions + .. [2] https://dlmf.nist.gov/4.23 + .. [3] https://functions.wolfram.com/ElementaryFunctions/ArcCsc + + """ + + @classmethod + def eval(cls, arg): + if arg.is_zero: + return S.ComplexInfinity + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.One: + return pi/2 + elif arg is S.NegativeOne: + return -pi/2 + if arg in [S.Infinity, S.NegativeInfinity, S.ComplexInfinity]: + return S.Zero + + if arg.could_extract_minus_sign(): + return -cls(-arg) + + if arg.is_infinite: + return S.Zero + + if arg.is_number: + acsc_table = cls._acsc_table() + if arg in acsc_table: + return acsc_table[arg] + + if isinstance(arg, csc): + ang = arg.args[0] + if ang.is_comparable: + ang %= 2*pi # restrict to [0,2*pi) + if ang > pi: # restrict to (-pi,pi] + ang = pi - ang + + # restrict to [-pi/2,pi/2] + if ang > pi/2: + ang = pi - ang + if ang < -pi/2: + ang = -pi - ang + + return ang + + if isinstance(arg, sec): # asec(x) + acsc(x) = pi/2 + ang = arg.args[0] + if ang.is_comparable: + return pi/2 - asec(arg) + + def fdiff(self, argindex=1): + if argindex == 1: + return -1/(self.args[0]**2*sqrt(1 - 1/self.args[0]**2)) + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + """ + return csc + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return pi/2 - S.ImaginaryUnit*log(2) + S.ImaginaryUnit*log(x) + elif n < 0 or n % 2 == 1: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) > 2 and n > 2: + p = previous_terms[-2] + return p * ((n - 1)*(n-2)) * x**2/(4 * (n//2)**2) + else: + k = n // 2 + R = RisingFactorial(S.Half, k) * n + F = factorial(k) * n // 2 * n // 2 + return S.ImaginaryUnit * R / F * x**n / 4 + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0).cancel() + if x0 is S.NaN: + return self.func(arg.as_leading_term(x)) + # Handling branch points + if x0 in (-S.One, S.One, S.Zero): + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + if x0 is S.ComplexInfinity: + return (1/arg).as_leading_term(x) + # Handling points lying on branch cuts (-1, 1) + if x0.is_real and (1 - x0**2).is_positive: + ndir = arg.dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if x0.is_positive: + return pi - self.func(x0) + elif im(ndir).is_positive: + if x0.is_negative: + return -pi - self.func(x0) + else: + return self.rewrite(log)._eval_as_leading_term(x, logx=logx, cdir=cdir).expand() + return self.func(x0) + + def _eval_nseries(self, x, n, logx, cdir=0): # acsc + from sympy.series.order import O + arg0 = self.args[0].subs(x, 0) + # Handling branch points + if arg0 is S.One: + t = Dummy('t', positive=True) + ser = acsc(S.One + t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.NegativeOne + self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + if arg0 is S.NegativeOne: + t = Dummy('t', positive=True) + ser = acsc(S.NegativeOne - t**2).rewrite(log).nseries(t, 0, 2*n) + arg1 = S.NegativeOne - self.args[0] + f = arg1.as_leading_term(x) + g = (arg1 - f)/ f + res1 = sqrt(S.One + g)._eval_nseries(x, n=n, logx=logx) + res = (res1.removeO()*sqrt(f)).expand() + return ser.removeO().subs(t, res).expand().powsimp() + O(x**n, x) + + res = super()._eval_nseries(x, n=n, logx=logx) + if arg0 is S.ComplexInfinity: + return res + # Handling points lying on branch cuts (-1, 1) + if arg0.is_real and (1 - arg0**2).is_positive: + ndir = self.args[0].dir(x, cdir if cdir else 1) + if im(ndir).is_negative: + if arg0.is_positive: + return pi - res + elif im(ndir).is_positive: + if arg0.is_negative: + return -pi - res + else: + return self.rewrite(log)._eval_nseries(x, n, logx=logx, cdir=cdir) + return res + + def _eval_rewrite_as_log(self, arg, **kwargs): + return -S.ImaginaryUnit*log(S.ImaginaryUnit/arg + sqrt(1 - 1/arg**2)) + + _eval_rewrite_as_tractable = _eval_rewrite_as_log + + def _eval_rewrite_as_asin(self, arg, **kwargs): + return asin(1/arg) + + def _eval_rewrite_as_acos(self, arg, **kwargs): + return pi/2 - acos(1/arg) + + def _eval_rewrite_as_atan(self, x, **kwargs): + return sqrt(x**2)/x*(pi/2 - atan(sqrt(x**2 - 1))) + + def _eval_rewrite_as_acot(self, arg, **kwargs): + return sqrt(arg**2)/arg*(pi/2 - acot(1/sqrt(arg**2 - 1))) + + def _eval_rewrite_as_asec(self, arg, **kwargs): + return pi/2 - asec(arg) + + +class atan2(InverseTrigonometricFunction): + r""" + The function ``atan2(y, x)`` computes `\operatorname{atan}(y/x)` taking + two arguments `y` and `x`. Signs of both `y` and `x` are considered to + determine the appropriate quadrant of `\operatorname{atan}(y/x)`. + The range is `(-\pi, \pi]`. The complete definition reads as follows: + + .. math:: + + \operatorname{atan2}(y, x) = + \begin{cases} + \arctan\left(\frac y x\right) & \qquad x > 0 \\ + \arctan\left(\frac y x\right) + \pi& \qquad y \ge 0, x < 0 \\ + \arctan\left(\frac y x\right) - \pi& \qquad y < 0, x < 0 \\ + +\frac{\pi}{2} & \qquad y > 0, x = 0 \\ + -\frac{\pi}{2} & \qquad y < 0, x = 0 \\ + \text{undefined} & \qquad y = 0, x = 0 + \end{cases} + + Attention: Note the role reversal of both arguments. The `y`-coordinate + is the first argument and the `x`-coordinate the second. + + If either `x` or `y` is complex: + + .. math:: + + \operatorname{atan2}(y, x) = + -i\log\left(\frac{x + iy}{\sqrt{x^2 + y^2}}\right) + + Examples + ======== + + Going counter-clock wise around the origin we find the + following angles: + + >>> from sympy import atan2 + >>> atan2(0, 1) + 0 + >>> atan2(1, 1) + pi/4 + >>> atan2(1, 0) + pi/2 + >>> atan2(1, -1) + 3*pi/4 + >>> atan2(0, -1) + pi + >>> atan2(-1, -1) + -3*pi/4 + >>> atan2(-1, 0) + -pi/2 + >>> atan2(-1, 1) + -pi/4 + + which are all correct. Compare this to the results of the ordinary + `\operatorname{atan}` function for the point `(x, y) = (-1, 1)` + + >>> from sympy import atan, S + >>> atan(S(1)/-1) + -pi/4 + >>> atan2(1, -1) + 3*pi/4 + + where only the `\operatorname{atan2}` function returns what we expect. + We can differentiate the function with respect to both arguments: + + >>> from sympy import diff + >>> from sympy.abc import x, y + >>> diff(atan2(y, x), x) + -y/(x**2 + y**2) + + >>> diff(atan2(y, x), y) + x/(x**2 + y**2) + + We can express the `\operatorname{atan2}` function in terms of + complex logarithms: + + >>> from sympy import log + >>> atan2(y, x).rewrite(log) + -I*log((x + I*y)/sqrt(x**2 + y**2)) + + and in terms of `\operatorname(atan)`: + + >>> from sympy import atan + >>> atan2(y, x).rewrite(atan) + Piecewise((2*atan(y/(x + sqrt(x**2 + y**2))), Ne(y, 0)), (pi, re(x) < 0), (0, Ne(x, 0)), (nan, True)) + + but note that this form is undefined on the negative real axis. + + See Also + ======== + + sin, csc, cos, sec, tan, cot + asin, acsc, acos, asec, atan, acot + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Inverse_trigonometric_functions + .. [2] https://en.wikipedia.org/wiki/Atan2 + .. [3] https://functions.wolfram.com/ElementaryFunctions/ArcTan2 + + """ + + @classmethod + def eval(cls, y, x): + from sympy.functions.special.delta_functions import Heaviside + if x is S.NegativeInfinity: + if y.is_zero: + # Special case y = 0 because we define Heaviside(0) = 1/2 + return pi + return 2*pi*(Heaviside(re(y))) - pi + elif x is S.Infinity: + return S.Zero + elif x.is_imaginary and y.is_imaginary and x.is_number and y.is_number: + x = im(x) + y = im(y) + + if x.is_extended_real and y.is_extended_real: + if x.is_positive: + return atan(y/x) + elif x.is_negative: + if y.is_negative: + return atan(y/x) - pi + elif y.is_nonnegative: + return atan(y/x) + pi + elif x.is_zero: + if y.is_positive: + return pi/2 + elif y.is_negative: + return -pi/2 + elif y.is_zero: + return S.NaN + if y.is_zero: + if x.is_extended_nonzero: + return pi*(S.One - Heaviside(x)) + if x.is_number: + return Piecewise((pi, re(x) < 0), + (0, Ne(x, 0)), + (S.NaN, True)) + if x.is_number and y.is_number: + return -S.ImaginaryUnit*log( + (x + S.ImaginaryUnit*y)/sqrt(x**2 + y**2)) + + def _eval_rewrite_as_log(self, y, x, **kwargs): + return -S.ImaginaryUnit*log((x + S.ImaginaryUnit*y)/sqrt(x**2 + y**2)) + + def _eval_rewrite_as_atan(self, y, x, **kwargs): + return Piecewise((2*atan(y/(x + sqrt(x**2 + y**2))), Ne(y, 0)), + (pi, re(x) < 0), + (0, Ne(x, 0)), + (S.NaN, True)) + + def _eval_rewrite_as_arg(self, y, x, **kwargs): + if x.is_extended_real and y.is_extended_real: + return arg_f(x + y*S.ImaginaryUnit) + n = x + S.ImaginaryUnit*y + d = x**2 + y**2 + return arg_f(n/sqrt(d)) - S.ImaginaryUnit*log(abs(n)/sqrt(abs(d))) + + def _eval_is_extended_real(self): + return self.args[0].is_extended_real and self.args[1].is_extended_real + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate(), self.args[1].conjugate()) + + def fdiff(self, argindex): + y, x = self.args + if argindex == 1: + # Diff wrt y + return x/(x**2 + y**2) + elif argindex == 2: + # Diff wrt x + return -y/(x**2 + y**2) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_evalf(self, prec): + y, x = self.args + if x.is_extended_real and y.is_extended_real: + return super()._eval_evalf(prec) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..ab52ace36a8dfbe73179dbf4419a54f7fa1af5fa --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/__init__.py @@ -0,0 +1 @@ +# Stub __init__.py for the sympy.functions.special package diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/benchmarks/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/benchmarks/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/benchmarks/bench_special.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/benchmarks/bench_special.py new file mode 100644 index 0000000000000000000000000000000000000000..25d7280c2cf31dcbff08065a78847ed03e0ebb05 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/benchmarks/bench_special.py @@ -0,0 +1,8 @@ +from sympy.core.symbol import symbols +from sympy.functions.special.spherical_harmonics import Ynm + +x, y = symbols('x,y') + + +def timeit_Ynm_xy(): + Ynm(1, 1, x, y) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/bessel.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/bessel.py new file mode 100644 index 0000000000000000000000000000000000000000..a24e7dc442d2a5a9bf7047113fd81b36c6b6ba36 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/bessel.py @@ -0,0 +1,2208 @@ +from functools import wraps + +from sympy.core import S +from sympy.core.add import Add +from sympy.core.cache import cacheit +from sympy.core.expr import Expr +from sympy.core.function import DefinedFunction, ArgumentIndexError, _mexpand +from sympy.core.logic import fuzzy_or, fuzzy_not +from sympy.core.numbers import Rational, pi, I +from sympy.core.power import Pow +from sympy.core.symbol import Dummy, uniquely_named_symbol, Wild +from sympy.core.sympify import sympify +from sympy.functions.combinatorial.factorials import factorial, RisingFactorial +from sympy.functions.elementary.trigonometric import sin, cos, csc, cot +from sympy.functions.elementary.integers import ceiling +from sympy.functions.elementary.exponential import exp, log +from sympy.functions.elementary.miscellaneous import cbrt, sqrt, root +from sympy.functions.elementary.complexes import (Abs, re, im, polar_lift, unpolarify) +from sympy.functions.special.gamma_functions import gamma, digamma, uppergamma +from sympy.functions.special.hyper import hyper +from sympy.polys.orthopolys import spherical_bessel_fn + +from mpmath import mp, workprec + +# TODO +# o Scorer functions G1 and G2 +# o Asymptotic expansions +# These are possible, e.g. for fixed order, but since the bessel type +# functions are oscillatory they are not actually tractable at +# infinity, so this is not particularly useful right now. +# o Nicer series expansions. +# o More rewriting. +# o Add solvers to ode.py (or rather add solvers for the hypergeometric equation). + + +class BesselBase(DefinedFunction): + """ + Abstract base class for Bessel-type functions. + + This class is meant to reduce code duplication. + All Bessel-type functions can 1) be differentiated, with the derivatives + expressed in terms of similar functions, and 2) be rewritten in terms + of other Bessel-type functions. + + Here, Bessel-type functions are assumed to have one complex parameter. + + To use this base class, define class attributes ``_a`` and ``_b`` such that + ``2*F_n' = -_a*F_{n+1} + b*F_{n-1}``. + + """ + + @property + def order(self): + """ The order of the Bessel-type function. """ + return self.args[0] + + @property + def argument(self): + """ The argument of the Bessel-type function. """ + return self.args[1] + + @classmethod + def eval(cls, nu, z): + return + + def fdiff(self, argindex=2): + if argindex != 2: + raise ArgumentIndexError(self, argindex) + return (self._b/2 * self.__class__(self.order - 1, self.argument) - + self._a/2 * self.__class__(self.order + 1, self.argument)) + + def _eval_conjugate(self): + z = self.argument + if z.is_extended_negative is False: + return self.__class__(self.order.conjugate(), z.conjugate()) + + def _eval_is_meromorphic(self, x, a): + nu, z = self.order, self.argument + + if nu.has(x): + return False + if not z._eval_is_meromorphic(x, a): + return None + z0 = z.subs(x, a) + if nu.is_integer: + if isinstance(self, (besselj, besseli, hn1, hn2, jn, yn)) or not nu.is_zero: + return fuzzy_not(z0.is_infinite) + return fuzzy_not(fuzzy_or([z0.is_zero, z0.is_infinite])) + + def _eval_expand_func(self, **hints): + nu, z, f = self.order, self.argument, self.__class__ + if nu.is_real: + if (nu - 1).is_positive: + return (-self._a*self._b*f(nu - 2, z)._eval_expand_func() + + 2*self._a*(nu - 1)*f(nu - 1, z)._eval_expand_func()/z) + elif (nu + 1).is_negative: + return (2*self._b*(nu + 1)*f(nu + 1, z)._eval_expand_func()/z - + self._a*self._b*f(nu + 2, z)._eval_expand_func()) + return self + + def _eval_simplify(self, **kwargs): + from sympy.simplify.simplify import besselsimp + return besselsimp(self) + + +class besselj(BesselBase): + r""" + Bessel function of the first kind. + + Explanation + =========== + + The Bessel $J$ function of order $\nu$ is defined to be the function + satisfying Bessel's differential equation + + .. math :: + z^2 \frac{\mathrm{d}^2 w}{\mathrm{d}z^2} + + z \frac{\mathrm{d}w}{\mathrm{d}z} + (z^2 - \nu^2) w = 0, + + with Laurent expansion + + .. math :: + J_\nu(z) = z^\nu \left(\frac{1}{\Gamma(\nu + 1) 2^\nu} + O(z^2) \right), + + if $\nu$ is not a negative integer. If $\nu=-n \in \mathbb{Z}_{<0}$ + *is* a negative integer, then the definition is + + .. math :: + J_{-n}(z) = (-1)^n J_n(z). + + Examples + ======== + + Create a Bessel function object: + + >>> from sympy import besselj, jn + >>> from sympy.abc import z, n + >>> b = besselj(n, z) + + Differentiate it: + + >>> b.diff(z) + besselj(n - 1, z)/2 - besselj(n + 1, z)/2 + + Rewrite in terms of spherical Bessel functions: + + >>> b.rewrite(jn) + sqrt(2)*sqrt(z)*jn(n - 1/2, z)/sqrt(pi) + + Access the parameter and argument: + + >>> b.order + n + >>> b.argument + z + + See Also + ======== + + bessely, besseli, besselk + + References + ========== + + .. [1] Abramowitz, Milton; Stegun, Irene A., eds. (1965), "Chapter 9", + Handbook of Mathematical Functions with Formulas, Graphs, and + Mathematical Tables + .. [2] Luke, Y. L. (1969), The Special Functions and Their + Approximations, Volume 1 + .. [3] https://en.wikipedia.org/wiki/Bessel_function + .. [4] https://functions.wolfram.com/Bessel-TypeFunctions/BesselJ/ + + """ + + _a = S.One + _b = S.One + + @classmethod + def eval(cls, nu, z): + if z.is_zero: + if nu.is_zero: + return S.One + elif (nu.is_integer and nu.is_zero is False) or re(nu).is_positive: + return S.Zero + elif re(nu).is_negative and not (nu.is_integer is True): + return S.ComplexInfinity + elif nu.is_imaginary: + return S.NaN + if z in (S.Infinity, S.NegativeInfinity): + return S.Zero + + if z.could_extract_minus_sign(): + return (z)**nu*(-z)**(-nu)*besselj(nu, -z) + if nu.is_integer: + if nu.could_extract_minus_sign(): + return S.NegativeOne**(-nu)*besselj(-nu, z) + newz = z.extract_multiplicatively(I) + if newz: # NOTE we don't want to change the function if z==0 + return I**(nu)*besseli(nu, newz) + + # branch handling: + if nu.is_integer: + newz = unpolarify(z) + if newz != z: + return besselj(nu, newz) + else: + newz, n = z.extract_branch_factor() + if n != 0: + return exp(2*n*pi*nu*I)*besselj(nu, newz) + nnu = unpolarify(nu) + if nu != nnu: + return besselj(nnu, z) + + def _eval_rewrite_as_besseli(self, nu, z, **kwargs): + return exp(I*pi*nu/2)*besseli(nu, polar_lift(-I)*z) + + def _eval_rewrite_as_bessely(self, nu, z, **kwargs): + if nu.is_integer is False: + return csc(pi*nu)*bessely(-nu, z) - cot(pi*nu)*bessely(nu, z) + + def _eval_rewrite_as_jn(self, nu, z, **kwargs): + return sqrt(2*z/pi)*jn(nu - S.Half, self.argument) + + def _eval_as_leading_term(self, x, logx, cdir): + nu, z = self.args + try: + arg = z.as_leading_term(x) + except NotImplementedError: + return self + c, e = arg.as_coeff_exponent(x) + + if e.is_positive: + return arg**nu/(2**nu*gamma(nu + 1)) + elif e.is_negative: + cdir = 1 if cdir == 0 else cdir + sign = c*cdir**e + if not sign.is_negative: + # Refer Abramowitz and Stegun 1965, p. 364 for more information on + # asymptotic approximation of besselj function. + return sqrt(2)*cos(z - pi*(2*nu + 1)/4)/sqrt(pi*z) + return self + + return super(besselj, self)._eval_as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_is_extended_real(self): + nu, z = self.args + if nu.is_integer and z.is_extended_real: + return True + + def _eval_nseries(self, x, n, logx, cdir=0): + # Refer https://functions.wolfram.com/Bessel-TypeFunctions/BesselJ/06/01/04/01/01/0003/ + # for more information on nseries expansion of besselj function. + from sympy.series.order import Order + nu, z = self.args + + # In case of powers less than 1, number of terms need to be computed + # separately to avoid repeated callings of _eval_nseries with wrong n + try: + _, exp = z.leadterm(x) + except (ValueError, NotImplementedError): + return self + + if exp.is_positive: + newn = ceiling(n/exp) + o = Order(x**n, x) + r = (z/2)._eval_nseries(x, n, logx, cdir).removeO() + if r is S.Zero: + return o + t = (_mexpand(r**2) + o).removeO() + + term = r**nu/gamma(nu + 1) + s = [term] + for k in range(1, (newn + 1)//2): + term *= -t/(k*(nu + k)) + term = (_mexpand(term) + o).removeO() + s.append(term) + return Add(*s) + o + + return super(besselj, self)._eval_nseries(x, n, logx, cdir) + + +class bessely(BesselBase): + r""" + Bessel function of the second kind. + + Explanation + =========== + + The Bessel $Y$ function of order $\nu$ is defined as + + .. math :: + Y_\nu(z) = \lim_{\mu \to \nu} \frac{J_\mu(z) \cos(\pi \mu) + - J_{-\mu}(z)}{\sin(\pi \mu)}, + + where $J_\mu(z)$ is the Bessel function of the first kind. + + It is a solution to Bessel's equation, and linearly independent from + $J_\nu$. + + Examples + ======== + + >>> from sympy import bessely, yn + >>> from sympy.abc import z, n + >>> b = bessely(n, z) + >>> b.diff(z) + bessely(n - 1, z)/2 - bessely(n + 1, z)/2 + >>> b.rewrite(yn) + sqrt(2)*sqrt(z)*yn(n - 1/2, z)/sqrt(pi) + + See Also + ======== + + besselj, besseli, besselk + + References + ========== + + .. [1] https://functions.wolfram.com/Bessel-TypeFunctions/BesselY/ + + """ + + _a = S.One + _b = S.One + + @classmethod + def eval(cls, nu, z): + if z.is_zero: + if nu.is_zero: + return S.NegativeInfinity + elif re(nu).is_zero is False: + return S.ComplexInfinity + elif re(nu).is_zero: + return S.NaN + if z in (S.Infinity, S.NegativeInfinity): + return S.Zero + if z == I*S.Infinity: + return exp(I*pi*(nu + 1)/2) * S.Infinity + if z == I*S.NegativeInfinity: + return exp(-I*pi*(nu + 1)/2) * S.Infinity + + if nu.is_integer: + if nu.could_extract_minus_sign(): + return S.NegativeOne**(-nu)*bessely(-nu, z) + + def _eval_rewrite_as_besselj(self, nu, z, **kwargs): + if nu.is_integer is False: + return csc(pi*nu)*(cos(pi*nu)*besselj(nu, z) - besselj(-nu, z)) + + def _eval_rewrite_as_besseli(self, nu, z, **kwargs): + aj = self._eval_rewrite_as_besselj(*self.args) + if aj: + return aj.rewrite(besseli) + + def _eval_rewrite_as_yn(self, nu, z, **kwargs): + return sqrt(2*z/pi) * yn(nu - S.Half, self.argument) + + def _eval_as_leading_term(self, x, logx, cdir): + nu, z = self.args + try: + arg = z.as_leading_term(x) + except NotImplementedError: + return self + c, e = arg.as_coeff_exponent(x) + + if e.is_positive: + term_one = ((2/pi)*log(z/2)*besselj(nu, z)) + term_two = -(z/2)**(-nu)*factorial(nu - 1)/pi if (nu).is_positive else S.Zero + term_three = -(z/2)**nu/(pi*factorial(nu))*(digamma(nu + 1) - S.EulerGamma) + arg = Add(*[term_one, term_two, term_three]).as_leading_term(x, logx=logx) + return arg + elif e.is_negative: + cdir = 1 if cdir == 0 else cdir + sign = c*cdir**e + if not sign.is_negative: + # Refer Abramowitz and Stegun 1965, p. 364 for more information on + # asymptotic approximation of bessely function. + return sqrt(2)*(-sin(pi*nu/2 - z + pi/4) + 3*cos(pi*nu/2 - z + pi/4)/(8*z))*sqrt(1/z)/sqrt(pi) + return self + + return super(bessely, self)._eval_as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_is_extended_real(self): + nu, z = self.args + if nu.is_integer and z.is_positive: + return True + + def _eval_nseries(self, x, n, logx, cdir=0): + # Refer https://functions.wolfram.com/Bessel-TypeFunctions/BesselY/06/01/04/01/02/0008/ + # for more information on nseries expansion of bessely function. + from sympy.series.order import Order + nu, z = self.args + + # In case of powers less than 1, number of terms need to be computed + # separately to avoid repeated callings of _eval_nseries with wrong n + try: + _, exp = z.leadterm(x) + except (ValueError, NotImplementedError): + return self + + if exp.is_positive and nu.is_integer: + newn = ceiling(n/exp) + bn = besselj(nu, z) + a = ((2/pi)*log(z/2)*bn)._eval_nseries(x, n, logx, cdir) + + b, c = [], [] + o = Order(x**n, x) + r = (z/2)._eval_nseries(x, n, logx, cdir).removeO() + if r is S.Zero: + return o + t = (_mexpand(r**2) + o).removeO() + + if nu > S.Zero: + term = r**(-nu)*factorial(nu - 1)/pi + b.append(term) + for k in range(1, nu): + denom = (nu - k)*k + if denom == S.Zero: + term *= t/k + else: + term *= t/denom + term = (_mexpand(term) + o).removeO() + b.append(term) + + p = r**nu/(pi*factorial(nu)) + term = p*(digamma(nu + 1) - S.EulerGamma) + c.append(term) + for k in range(1, (newn + 1)//2): + p *= -t/(k*(k + nu)) + p = (_mexpand(p) + o).removeO() + term = p*(digamma(k + nu + 1) + digamma(k + 1)) + c.append(term) + return a - Add(*b) - Add(*c) # Order term comes from a + + return super(bessely, self)._eval_nseries(x, n, logx, cdir) + + +class besseli(BesselBase): + r""" + Modified Bessel function of the first kind. + + Explanation + =========== + + The Bessel $I$ function is a solution to the modified Bessel equation + + .. math :: + z^2 \frac{\mathrm{d}^2 w}{\mathrm{d}z^2} + + z \frac{\mathrm{d}w}{\mathrm{d}z} + (z^2 + \nu^2)^2 w = 0. + + It can be defined as + + .. math :: + I_\nu(z) = i^{-\nu} J_\nu(iz), + + where $J_\nu(z)$ is the Bessel function of the first kind. + + Examples + ======== + + >>> from sympy import besseli + >>> from sympy.abc import z, n + >>> besseli(n, z).diff(z) + besseli(n - 1, z)/2 + besseli(n + 1, z)/2 + + See Also + ======== + + besselj, bessely, besselk + + References + ========== + + .. [1] https://functions.wolfram.com/Bessel-TypeFunctions/BesselI/ + + """ + + _a = -S.One + _b = S.One + + @classmethod + def eval(cls, nu, z): + if z.is_zero: + if nu.is_zero: + return S.One + elif (nu.is_integer and nu.is_zero is False) or re(nu).is_positive: + return S.Zero + elif re(nu).is_negative and not (nu.is_integer is True): + return S.ComplexInfinity + elif nu.is_imaginary: + return S.NaN + if im(z) in (S.Infinity, S.NegativeInfinity): + return S.Zero + if z is S.Infinity: + return S.Infinity + if z is S.NegativeInfinity: + return (-1)**nu*S.Infinity + + if z.could_extract_minus_sign(): + return (z)**nu*(-z)**(-nu)*besseli(nu, -z) + if nu.is_integer: + if nu.could_extract_minus_sign(): + return besseli(-nu, z) + newz = z.extract_multiplicatively(I) + if newz: # NOTE we don't want to change the function if z==0 + return I**(-nu)*besselj(nu, -newz) + + # branch handling: + if nu.is_integer: + newz = unpolarify(z) + if newz != z: + return besseli(nu, newz) + else: + newz, n = z.extract_branch_factor() + if n != 0: + return exp(2*n*pi*nu*I)*besseli(nu, newz) + nnu = unpolarify(nu) + if nu != nnu: + return besseli(nnu, z) + + def _eval_rewrite_as_tractable(self, nu, z, limitvar=None, **kwargs): + if z.is_extended_real: + return exp(z)*_besseli(nu, z) + + def _eval_rewrite_as_besselj(self, nu, z, **kwargs): + return exp(-I*pi*nu/2)*besselj(nu, polar_lift(I)*z) + + def _eval_rewrite_as_bessely(self, nu, z, **kwargs): + aj = self._eval_rewrite_as_besselj(*self.args) + if aj: + return aj.rewrite(bessely) + + def _eval_rewrite_as_jn(self, nu, z, **kwargs): + return self._eval_rewrite_as_besselj(*self.args).rewrite(jn) + + def _eval_is_extended_real(self): + nu, z = self.args + if nu.is_integer and z.is_extended_real: + return True + + def _eval_as_leading_term(self, x, logx, cdir): + nu, z = self.args + try: + arg = z.as_leading_term(x) + except NotImplementedError: + return self + c, e = arg.as_coeff_exponent(x) + + if e.is_positive: + return arg**nu/(2**nu*gamma(nu + 1)) + elif e.is_negative: + cdir = 1 if cdir == 0 else cdir + sign = c*cdir**e + if not sign.is_negative: + # Refer Abramowitz and Stegun 1965, p. 377 for more information on + # asymptotic approximation of besseli function. + return exp(z)/sqrt(2*pi*z) + return self + + return super(besseli, self)._eval_as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_nseries(self, x, n, logx, cdir=0): + # Refer https://functions.wolfram.com/Bessel-TypeFunctions/BesselI/06/01/04/01/01/0003/ + # for more information on nseries expansion of besseli function. + from sympy.series.order import Order + nu, z = self.args + + # In case of powers less than 1, number of terms need to be computed + # separately to avoid repeated callings of _eval_nseries with wrong n + try: + _, exp = z.leadterm(x) + except (ValueError, NotImplementedError): + return self + + if exp.is_positive: + newn = ceiling(n/exp) + o = Order(x**n, x) + r = (z/2)._eval_nseries(x, n, logx, cdir).removeO() + if r is S.Zero: + return o + t = (_mexpand(r**2) + o).removeO() + + term = r**nu/gamma(nu + 1) + s = [term] + for k in range(1, (newn + 1)//2): + term *= t/(k*(nu + k)) + term = (_mexpand(term) + o).removeO() + s.append(term) + return Add(*s) + o + + return super(besseli, self)._eval_nseries(x, n, logx, cdir) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.functions.combinatorial.factorials import RisingFactorial + from sympy.series.order import Order + point = args0[1] + + if point in [S.Infinity, S.NegativeInfinity]: + nu, z = self.args + s = [(RisingFactorial(Rational(2*nu - 1, 2), k)*RisingFactorial(Rational(2*nu + 1, 2), k))/\ + ((2)**(k)*z**(Rational(2*k + 1, 2))*factorial(k)) for k in range(n)] + [Order(1/z**(Rational(2*n + 1, 2)), x)] + return exp(z)/sqrt(2*pi) * (Add(*s)) + + return super()._eval_aseries(n, args0, x, logx) + + +class besselk(BesselBase): + r""" + Modified Bessel function of the second kind. + + Explanation + =========== + + The Bessel $K$ function of order $\nu$ is defined as + + .. math :: + K_\nu(z) = \lim_{\mu \to \nu} \frac{\pi}{2} + \frac{I_{-\mu}(z) -I_\mu(z)}{\sin(\pi \mu)}, + + where $I_\mu(z)$ is the modified Bessel function of the first kind. + + It is a solution of the modified Bessel equation, and linearly independent + from $Y_\nu$. + + Examples + ======== + + >>> from sympy import besselk + >>> from sympy.abc import z, n + >>> besselk(n, z).diff(z) + -besselk(n - 1, z)/2 - besselk(n + 1, z)/2 + + See Also + ======== + + besselj, besseli, bessely + + References + ========== + + .. [1] https://functions.wolfram.com/Bessel-TypeFunctions/BesselK/ + + """ + + _a = S.One + _b = -S.One + + @classmethod + def eval(cls, nu, z): + if z.is_zero: + if nu.is_zero: + return S.Infinity + elif re(nu).is_zero is False: + return S.ComplexInfinity + elif re(nu).is_zero: + return S.NaN + if z in (S.Infinity, I*S.Infinity, I*S.NegativeInfinity): + return S.Zero + + if nu.is_integer: + if nu.could_extract_minus_sign(): + return besselk(-nu, z) + + def _eval_rewrite_as_besseli(self, nu, z, **kwargs): + if nu.is_integer is False: + return pi*csc(pi*nu)*(besseli(-nu, z) - besseli(nu, z))/2 + + def _eval_rewrite_as_besselj(self, nu, z, **kwargs): + ai = self._eval_rewrite_as_besseli(*self.args) + if ai: + return ai.rewrite(besselj) + + def _eval_rewrite_as_bessely(self, nu, z, **kwargs): + aj = self._eval_rewrite_as_besselj(*self.args) + if aj: + return aj.rewrite(bessely) + + def _eval_rewrite_as_yn(self, nu, z, **kwargs): + ay = self._eval_rewrite_as_bessely(*self.args) + if ay: + return ay.rewrite(yn) + + def _eval_is_extended_real(self): + nu, z = self.args + if nu.is_integer and z.is_positive: + return True + + def _eval_rewrite_as_tractable(self, nu, z, limitvar=None, **kwargs): + if z.is_extended_real: + return exp(-z)*_besselk(nu, z) + + def _eval_as_leading_term(self, x, logx, cdir): + nu, z = self.args + try: + arg = z.as_leading_term(x) + except NotImplementedError: + return self + _, e = arg.as_coeff_exponent(x) + + if e.is_positive: + if nu.is_zero: + # Equation 9.6.8 of Abramowitz and Stegun (10th ed, 1972). + term = -log(z) - S.EulerGamma + log(2) + elif nu.is_nonzero: + # Equation 9.6.9 of Abramowitz and Stegun (10th ed, 1972). + term = gamma(Abs(nu))*(z/2)**(-Abs(nu))/2 + else: + raise NotImplementedError(f"Cannot proceed without knowing if {nu} is zero or not.") + + return term.as_leading_term(x, logx=logx) + elif e.is_negative: + # Equation 9.7.2 of Abramowitz and Stegun (10th ed, 1972). + return sqrt(pi)*exp(-arg)/sqrt(2*arg) + else: + return self.func(nu, arg) + + def _eval_nseries(self, x, n, logx, cdir=0): + from sympy.series.order import Order + nu, z = self.args + + try: + _, exp = z.leadterm(x) + except (ValueError, NotImplementedError): + return self + + # In case of powers less than 1, number of terms need to be computed + # separately to avoid repeated callings of _eval_nseries with wrong n + if exp.is_positive: + r = (z/2)._eval_nseries(x, n, logx, cdir).removeO() + if r is S.Zero: + return Order(z**(-nu) + z**nu, x) + + o = Order(x**n, x) + if nu.is_integer: + # Reference: https://functions.wolfram.com/Bessel-TypeFunctions/BesselK/06/01/04/01/02/0008/ (only for integer order) + newn = ceiling(n/exp) + bn = besseli(nu, z) + a = ((-1)**(nu - 1)*log(z/2)*bn)._eval_nseries(x, n, logx, cdir) + + b, c = [], [] + t = _mexpand(r**2) + + if nu > S.Zero: + term = r**(-nu)*factorial(nu - 1)/2 + b.append(term) + for k in range(1, nu): + term *= t/((k - nu)*k) + term = (_mexpand(term) + o).removeO() + b.append(term) + + p = r**nu*(-1)**nu/(2*factorial(nu)) + term = p*(digamma(nu + 1) - S.EulerGamma) + c.append(term) + for k in range(1, (newn + 1)//2): + p *= t/(k*(k + nu)) + p = (_mexpand(p) + o).removeO() + term = p*(digamma(k + nu + 1) + digamma(k + 1)) + c.append(term) + return a + Add(*b) + Add(*c) + o + elif nu.is_noninteger: + # Reference: https://functions.wolfram.com/Bessel-TypeFunctions/BesselK/06/01/04/01/01/0003/ + # (only for non-integer order). + # While the expression in the reference above seems correct + # for non-real order as well, it would need some manipulation + # (not implemented) to be written as a power series in x with + # real exponents [e.g. Dunster 1990. "Bessel functions + # of purely imaginary order, with an application to second-order + # linear differential equations having a large parameter". + # SIAM J. Math. Anal. Vol 21, No. 4, pp 995-1018.]. + newn_a = ceiling((n+nu)/exp) + newn_b = ceiling((n-nu)/exp) + + a, b = [], [] + for k in range((newn_a+1)//2): + term = gamma(nu)*r**(2*k-nu)/(2*RisingFactorial(1-nu, k)*factorial(k)) + a.append(_mexpand(term)) + for k in range((newn_b+1)//2): + term = gamma(-nu)*r**(2*k+nu)/(2*RisingFactorial(nu+1, k)*factorial(k)) + b.append(_mexpand(term)) + return Add(*a) + Add(*b) + o + else: + raise NotImplementedError("besselk expansion is only implemented for real order") + + return super(besselk, self)._eval_nseries(x, n, logx, cdir) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.functions.combinatorial.factorials import RisingFactorial + from sympy.series.order import Order + point = args0[1] + + if point in [S.Infinity, S.NegativeInfinity]: + nu, z = self.args + s = [(RisingFactorial(Rational(2*nu - 1, 2), k)*RisingFactorial(Rational(2*nu + 1, 2), k))/\ + ((-2)**(k)*z**(Rational(2*k + 1, 2))*factorial(k)) for k in range(n)] +[Order(1/z**(Rational(2*n + 1, 2)), x)] + return (exp(-z)*sqrt(pi/2))*Add(*s) + + return super()._eval_aseries(n, args0, x, logx) + + +class hankel1(BesselBase): + r""" + Hankel function of the first kind. + + Explanation + =========== + + This function is defined as + + .. math :: + H_\nu^{(1)} = J_\nu(z) + iY_\nu(z), + + where $J_\nu(z)$ is the Bessel function of the first kind, and + $Y_\nu(z)$ is the Bessel function of the second kind. + + It is a solution to Bessel's equation. + + Examples + ======== + + >>> from sympy import hankel1 + >>> from sympy.abc import z, n + >>> hankel1(n, z).diff(z) + hankel1(n - 1, z)/2 - hankel1(n + 1, z)/2 + + See Also + ======== + + hankel2, besselj, bessely + + References + ========== + + .. [1] https://functions.wolfram.com/Bessel-TypeFunctions/HankelH1/ + + """ + + _a = S.One + _b = S.One + + def _eval_conjugate(self): + z = self.argument + if z.is_extended_negative is False: + return hankel2(self.order.conjugate(), z.conjugate()) + + +class hankel2(BesselBase): + r""" + Hankel function of the second kind. + + Explanation + =========== + + This function is defined as + + .. math :: + H_\nu^{(2)} = J_\nu(z) - iY_\nu(z), + + where $J_\nu(z)$ is the Bessel function of the first kind, and + $Y_\nu(z)$ is the Bessel function of the second kind. + + It is a solution to Bessel's equation, and linearly independent from + $H_\nu^{(1)}$. + + Examples + ======== + + >>> from sympy import hankel2 + >>> from sympy.abc import z, n + >>> hankel2(n, z).diff(z) + hankel2(n - 1, z)/2 - hankel2(n + 1, z)/2 + + See Also + ======== + + hankel1, besselj, bessely + + References + ========== + + .. [1] https://functions.wolfram.com/Bessel-TypeFunctions/HankelH2/ + + """ + + _a = S.One + _b = S.One + + def _eval_conjugate(self): + z = self.argument + if z.is_extended_negative is False: + return hankel1(self.order.conjugate(), z.conjugate()) + + +def assume_integer_order(fn): + @wraps(fn) + def g(self, nu, z): + if nu.is_integer: + return fn(self, nu, z) + return g + + +class SphericalBesselBase(BesselBase): + """ + Base class for spherical Bessel functions. + + These are thin wrappers around ordinary Bessel functions, + since spherical Bessel functions differ from the ordinary + ones just by a slight change in order. + + To use this class, define the ``_eval_evalf()`` and ``_expand()`` methods. + + """ + + def _expand(self, **hints): + """ Expand self into a polynomial. Nu is guaranteed to be Integer. """ + raise NotImplementedError('expansion') + + def _eval_expand_func(self, **hints): + if self.order.is_Integer: + return self._expand(**hints) + return self + + def fdiff(self, argindex=2): + if argindex != 2: + raise ArgumentIndexError(self, argindex) + return self.__class__(self.order - 1, self.argument) - \ + self * (self.order + 1)/self.argument + + +def _jn(n, z): + return (spherical_bessel_fn(n, z)*sin(z) + + S.NegativeOne**(n + 1)*spherical_bessel_fn(-n - 1, z)*cos(z)) + + +def _yn(n, z): + # (-1)**(n + 1) * _jn(-n - 1, z) + return (S.NegativeOne**(n + 1) * spherical_bessel_fn(-n - 1, z)*sin(z) - + spherical_bessel_fn(n, z)*cos(z)) + + +class jn(SphericalBesselBase): + r""" + Spherical Bessel function of the first kind. + + Explanation + =========== + + This function is a solution to the spherical Bessel equation + + .. math :: + z^2 \frac{\mathrm{d}^2 w}{\mathrm{d}z^2} + + 2z \frac{\mathrm{d}w}{\mathrm{d}z} + (z^2 - \nu(\nu + 1)) w = 0. + + It can be defined as + + .. math :: + j_\nu(z) = \sqrt{\frac{\pi}{2z}} J_{\nu + \frac{1}{2}}(z), + + where $J_\nu(z)$ is the Bessel function of the first kind. + + The spherical Bessel functions of integral order are + calculated using the formula: + + .. math:: j_n(z) = f_n(z) \sin{z} + (-1)^{n+1} f_{-n-1}(z) \cos{z}, + + where the coefficients $f_n(z)$ are available as + :func:`sympy.polys.orthopolys.spherical_bessel_fn`. + + Examples + ======== + + >>> from sympy import Symbol, jn, sin, cos, expand_func, besselj, bessely + >>> z = Symbol("z") + >>> nu = Symbol("nu", integer=True) + >>> print(expand_func(jn(0, z))) + sin(z)/z + >>> expand_func(jn(1, z)) == sin(z)/z**2 - cos(z)/z + True + >>> expand_func(jn(3, z)) + (-6/z**2 + 15/z**4)*sin(z) + (1/z - 15/z**3)*cos(z) + >>> jn(nu, z).rewrite(besselj) + sqrt(2)*sqrt(pi)*sqrt(1/z)*besselj(nu + 1/2, z)/2 + >>> jn(nu, z).rewrite(bessely) + (-1)**nu*sqrt(2)*sqrt(pi)*sqrt(1/z)*bessely(-nu - 1/2, z)/2 + >>> jn(2, 5.2+0.3j).evalf(20) + 0.099419756723640344491 - 0.054525080242173562897*I + + See Also + ======== + + besselj, bessely, besselk, yn + + References + ========== + + .. [1] https://dlmf.nist.gov/10.47 + + """ + @classmethod + def eval(cls, nu, z): + if z.is_zero: + if nu.is_zero: + return S.One + elif nu.is_integer: + if nu.is_positive: + return S.Zero + else: + return S.ComplexInfinity + if z in (S.NegativeInfinity, S.Infinity): + return S.Zero + + def _eval_rewrite_as_besselj(self, nu, z, **kwargs): + return sqrt(pi/(2*z)) * besselj(nu + S.Half, z) + + def _eval_rewrite_as_bessely(self, nu, z, **kwargs): + return S.NegativeOne**nu * sqrt(pi/(2*z)) * bessely(-nu - S.Half, z) + + def _eval_rewrite_as_yn(self, nu, z, **kwargs): + return S.NegativeOne**(nu) * yn(-nu - 1, z) + + def _expand(self, **hints): + return _jn(self.order, self.argument) + + def _eval_evalf(self, prec): + if self.order.is_Integer: + return self.rewrite(besselj)._eval_evalf(prec) + + +class yn(SphericalBesselBase): + r""" + Spherical Bessel function of the second kind. + + Explanation + =========== + + This function is another solution to the spherical Bessel equation, and + linearly independent from $j_n$. It can be defined as + + .. math :: + y_\nu(z) = \sqrt{\frac{\pi}{2z}} Y_{\nu + \frac{1}{2}}(z), + + where $Y_\nu(z)$ is the Bessel function of the second kind. + + For integral orders $n$, $y_n$ is calculated using the formula: + + .. math:: y_n(z) = (-1)^{n+1} j_{-n-1}(z) + + Examples + ======== + + >>> from sympy import Symbol, yn, sin, cos, expand_func, besselj, bessely + >>> z = Symbol("z") + >>> nu = Symbol("nu", integer=True) + >>> print(expand_func(yn(0, z))) + -cos(z)/z + >>> expand_func(yn(1, z)) == -cos(z)/z**2-sin(z)/z + True + >>> yn(nu, z).rewrite(besselj) + (-1)**(nu + 1)*sqrt(2)*sqrt(pi)*sqrt(1/z)*besselj(-nu - 1/2, z)/2 + >>> yn(nu, z).rewrite(bessely) + sqrt(2)*sqrt(pi)*sqrt(1/z)*bessely(nu + 1/2, z)/2 + >>> yn(2, 5.2+0.3j).evalf(20) + 0.18525034196069722536 + 0.014895573969924817587*I + + See Also + ======== + + besselj, bessely, besselk, jn + + References + ========== + + .. [1] https://dlmf.nist.gov/10.47 + + """ + @assume_integer_order + def _eval_rewrite_as_besselj(self, nu, z, **kwargs): + return S.NegativeOne**(nu+1) * sqrt(pi/(2*z)) * besselj(-nu - S.Half, z) + + @assume_integer_order + def _eval_rewrite_as_bessely(self, nu, z, **kwargs): + return sqrt(pi/(2*z)) * bessely(nu + S.Half, z) + + def _eval_rewrite_as_jn(self, nu, z, **kwargs): + return S.NegativeOne**(nu + 1) * jn(-nu - 1, z) + + def _expand(self, **hints): + return _yn(self.order, self.argument) + + def _eval_evalf(self, prec): + if self.order.is_Integer: + return self.rewrite(bessely)._eval_evalf(prec) + + +class SphericalHankelBase(SphericalBesselBase): + + @assume_integer_order + def _eval_rewrite_as_besselj(self, nu, z, **kwargs): + # jn +- I*yn + # jn as beeselj: sqrt(pi/(2*z)) * besselj(nu + S.Half, z) + # yn as besselj: (-1)**(nu+1) * sqrt(pi/(2*z)) * besselj(-nu - S.Half, z) + hks = self._hankel_kind_sign + return sqrt(pi/(2*z))*(besselj(nu + S.Half, z) + + hks*I*S.NegativeOne**(nu+1)*besselj(-nu - S.Half, z)) + + @assume_integer_order + def _eval_rewrite_as_bessely(self, nu, z, **kwargs): + # jn +- I*yn + # jn as bessely: (-1)**nu * sqrt(pi/(2*z)) * bessely(-nu - S.Half, z) + # yn as bessely: sqrt(pi/(2*z)) * bessely(nu + S.Half, z) + hks = self._hankel_kind_sign + return sqrt(pi/(2*z))*(S.NegativeOne**nu*bessely(-nu - S.Half, z) + + hks*I*bessely(nu + S.Half, z)) + + def _eval_rewrite_as_yn(self, nu, z, **kwargs): + hks = self._hankel_kind_sign + return jn(nu, z).rewrite(yn) + hks*I*yn(nu, z) + + def _eval_rewrite_as_jn(self, nu, z, **kwargs): + hks = self._hankel_kind_sign + return jn(nu, z) + hks*I*yn(nu, z).rewrite(jn) + + def _eval_expand_func(self, **hints): + if self.order.is_Integer: + return self._expand(**hints) + else: + nu = self.order + z = self.argument + hks = self._hankel_kind_sign + return jn(nu, z) + hks*I*yn(nu, z) + + def _expand(self, **hints): + n = self.order + z = self.argument + hks = self._hankel_kind_sign + + # fully expanded version + # return ((fn(n, z) * sin(z) + + # (-1)**(n + 1) * fn(-n - 1, z) * cos(z)) + # jn + # (hks * I * (-1)**(n + 1) * + # (fn(-n - 1, z) * hk * I * sin(z) + + # (-1)**(-n) * fn(n, z) * I * cos(z))) # +-I*yn + # ) + + return (_jn(n, z) + hks*I*_yn(n, z)).expand() + + def _eval_evalf(self, prec): + if self.order.is_Integer: + return self.rewrite(besselj)._eval_evalf(prec) + + +class hn1(SphericalHankelBase): + r""" + Spherical Hankel function of the first kind. + + Explanation + =========== + + This function is defined as + + .. math:: h_\nu^(1)(z) = j_\nu(z) + i y_\nu(z), + + where $j_\nu(z)$ and $y_\nu(z)$ are the spherical + Bessel function of the first and second kinds. + + For integral orders $n$, $h_n^(1)$ is calculated using the formula: + + .. math:: h_n^(1)(z) = j_{n}(z) + i (-1)^{n+1} j_{-n-1}(z) + + Examples + ======== + + >>> from sympy import Symbol, hn1, hankel1, expand_func, yn, jn + >>> z = Symbol("z") + >>> nu = Symbol("nu", integer=True) + >>> print(expand_func(hn1(nu, z))) + jn(nu, z) + I*yn(nu, z) + >>> print(expand_func(hn1(0, z))) + sin(z)/z - I*cos(z)/z + >>> print(expand_func(hn1(1, z))) + -I*sin(z)/z - cos(z)/z + sin(z)/z**2 - I*cos(z)/z**2 + >>> hn1(nu, z).rewrite(jn) + (-1)**(nu + 1)*I*jn(-nu - 1, z) + jn(nu, z) + >>> hn1(nu, z).rewrite(yn) + (-1)**nu*yn(-nu - 1, z) + I*yn(nu, z) + >>> hn1(nu, z).rewrite(hankel1) + sqrt(2)*sqrt(pi)*sqrt(1/z)*hankel1(nu, z)/2 + + See Also + ======== + + hn2, jn, yn, hankel1, hankel2 + + References + ========== + + .. [1] https://dlmf.nist.gov/10.47 + + """ + + _hankel_kind_sign = S.One + + @assume_integer_order + def _eval_rewrite_as_hankel1(self, nu, z, **kwargs): + return sqrt(pi/(2*z))*hankel1(nu, z) + + +class hn2(SphericalHankelBase): + r""" + Spherical Hankel function of the second kind. + + Explanation + =========== + + This function is defined as + + .. math:: h_\nu^(2)(z) = j_\nu(z) - i y_\nu(z), + + where $j_\nu(z)$ and $y_\nu(z)$ are the spherical + Bessel function of the first and second kinds. + + For integral orders $n$, $h_n^(2)$ is calculated using the formula: + + .. math:: h_n^(2)(z) = j_{n} - i (-1)^{n+1} j_{-n-1}(z) + + Examples + ======== + + >>> from sympy import Symbol, hn2, hankel2, expand_func, jn, yn + >>> z = Symbol("z") + >>> nu = Symbol("nu", integer=True) + >>> print(expand_func(hn2(nu, z))) + jn(nu, z) - I*yn(nu, z) + >>> print(expand_func(hn2(0, z))) + sin(z)/z + I*cos(z)/z + >>> print(expand_func(hn2(1, z))) + I*sin(z)/z - cos(z)/z + sin(z)/z**2 + I*cos(z)/z**2 + >>> hn2(nu, z).rewrite(hankel2) + sqrt(2)*sqrt(pi)*sqrt(1/z)*hankel2(nu, z)/2 + >>> hn2(nu, z).rewrite(jn) + -(-1)**(nu + 1)*I*jn(-nu - 1, z) + jn(nu, z) + >>> hn2(nu, z).rewrite(yn) + (-1)**nu*yn(-nu - 1, z) - I*yn(nu, z) + + See Also + ======== + + hn1, jn, yn, hankel1, hankel2 + + References + ========== + + .. [1] https://dlmf.nist.gov/10.47 + + """ + + _hankel_kind_sign = -S.One + + @assume_integer_order + def _eval_rewrite_as_hankel2(self, nu, z, **kwargs): + return sqrt(pi/(2*z))*hankel2(nu, z) + + +def jn_zeros(n, k, method="sympy", dps=15): + """ + Zeros of the spherical Bessel function of the first kind. + + Explanation + =========== + + This returns an array of zeros of $jn$ up to the $k$-th zero. + + * method = "sympy": uses `mpmath.besseljzero + `_ + * method = "scipy": uses the + `SciPy's sph_jn `_ + and + `newton `_ + to find all + roots, which is faster than computing the zeros using a general + numerical solver, but it requires SciPy and only works with low + precision floating point numbers. (The function used with + method="sympy" is a recent addition to mpmath; before that a general + solver was used.) + + Examples + ======== + + >>> from sympy import jn_zeros + >>> jn_zeros(2, 4, dps=5) + [5.7635, 9.095, 12.323, 15.515] + + See Also + ======== + + jn, yn, besselj, besselk, bessely + + Parameters + ========== + + n : integer + order of Bessel function + + k : integer + number of zeros to return + + + """ + from math import pi as math_pi + + if method == "sympy": + from mpmath import besseljzero + from mpmath.libmp.libmpf import dps_to_prec + prec = dps_to_prec(dps) + return [Expr._from_mpmath(besseljzero(S(n + 0.5)._to_mpmath(prec), + int(l)), prec) + for l in range(1, k + 1)] + elif method == "scipy": + from scipy.optimize import newton + try: + from scipy.special import spherical_jn + f = lambda x: spherical_jn(n, x) + except ImportError: + from scipy.special import sph_jn + f = lambda x: sph_jn(n, x)[0][-1] + else: + raise NotImplementedError("Unknown method.") + + def solver(f, x): + if method == "scipy": + root = newton(f, x) + else: + raise NotImplementedError("Unknown method.") + return root + + # we need to approximate the position of the first root: + root = n + math_pi + # determine the first root exactly: + root = solver(f, root) + roots = [root] + for i in range(k - 1): + # estimate the position of the next root using the last root + pi: + root = solver(f, root + math_pi) + roots.append(root) + return roots + + +class AiryBase(DefinedFunction): + """ + Abstract base class for Airy functions. + + This class is meant to reduce code duplication. + + """ + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def _eval_is_extended_real(self): + return self.args[0].is_extended_real + + def as_real_imag(self, deep=True, **hints): + z = self.args[0] + zc = z.conjugate() + f = self.func + u = (f(z)+f(zc))/2 + v = I*(f(zc)-f(z))/2 + return u, v + + def _eval_expand_complex(self, deep=True, **hints): + re_part, im_part = self.as_real_imag(deep=deep, **hints) + return re_part + im_part*I + + +class airyai(AiryBase): + r""" + The Airy function $\operatorname{Ai}$ of the first kind. + + Explanation + =========== + + The Airy function $\operatorname{Ai}(z)$ is defined to be the function + satisfying Airy's differential equation + + .. math:: + \frac{\mathrm{d}^2 w(z)}{\mathrm{d}z^2} - z w(z) = 0. + + Equivalently, for real $z$ + + .. math:: + \operatorname{Ai}(z) := \frac{1}{\pi} + \int_0^\infty \cos\left(\frac{t^3}{3} + z t\right) \mathrm{d}t. + + Examples + ======== + + Create an Airy function object: + + >>> from sympy import airyai + >>> from sympy.abc import z + + >>> airyai(z) + airyai(z) + + Several special values are known: + + >>> airyai(0) + 3**(1/3)/(3*gamma(2/3)) + >>> from sympy import oo + >>> airyai(oo) + 0 + >>> airyai(-oo) + 0 + + The Airy function obeys the mirror symmetry: + + >>> from sympy import conjugate + >>> conjugate(airyai(z)) + airyai(conjugate(z)) + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(airyai(z), z) + airyaiprime(z) + >>> diff(airyai(z), z, 2) + z*airyai(z) + + Series expansion is also supported: + + >>> from sympy import series + >>> series(airyai(z), z, 0, 3) + 3**(5/6)*gamma(1/3)/(6*pi) - 3**(1/6)*z*gamma(2/3)/(2*pi) + O(z**3) + + We can numerically evaluate the Airy function to arbitrary precision + on the whole complex plane: + + >>> airyai(-2).evalf(50) + 0.22740742820168557599192443603787379946077222541710 + + Rewrite $\operatorname{Ai}(z)$ in terms of hypergeometric functions: + + >>> from sympy import hyper + >>> airyai(z).rewrite(hyper) + -3**(2/3)*z*hyper((), (4/3,), z**3/9)/(3*gamma(1/3)) + 3**(1/3)*hyper((), (2/3,), z**3/9)/(3*gamma(2/3)) + + See Also + ======== + + airybi: Airy function of the second kind. + airyaiprime: Derivative of the Airy function of the first kind. + airybiprime: Derivative of the Airy function of the second kind. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Airy_function + .. [2] https://dlmf.nist.gov/9 + .. [3] https://encyclopediaofmath.org/wiki/Airy_functions + .. [4] https://mathworld.wolfram.com/AiryFunctions.html + + """ + + nargs = 1 + unbranched = True + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Zero + elif arg is S.NegativeInfinity: + return S.Zero + elif arg.is_zero: + return S.One / (3**Rational(2, 3) * gamma(Rational(2, 3))) + if arg.is_zero: + return S.One / (3**Rational(2, 3) * gamma(Rational(2, 3))) + + def fdiff(self, argindex=1): + if argindex == 1: + return airyaiprime(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) > 1: + p = previous_terms[-1] + return ((cbrt(3)*x)**(-n)*(cbrt(3)*x)**(n + 1)*sin(pi*(n*Rational(2, 3) + Rational(4, 3)))*factorial(n) * + gamma(n/3 + Rational(2, 3))/(sin(pi*(n*Rational(2, 3) + Rational(2, 3)))*factorial(n + 1)*gamma(n/3 + Rational(1, 3))) * p) + else: + return (S.One/(3**Rational(2, 3)*pi) * gamma((n+S.One)/S(3)) * sin(Rational(2, 3)*pi*(n+S.One)) / + factorial(n) * (cbrt(3)*x)**n) + + def _eval_rewrite_as_besselj(self, z, **kwargs): + ot = Rational(1, 3) + tt = Rational(2, 3) + a = Pow(-z, Rational(3, 2)) + if re(z).is_negative: + return ot*sqrt(-z) * (besselj(-ot, tt*a) + besselj(ot, tt*a)) + + def _eval_rewrite_as_besseli(self, z, **kwargs): + ot = Rational(1, 3) + tt = Rational(2, 3) + a = Pow(z, Rational(3, 2)) + if re(z).is_positive: + return ot*sqrt(z) * (besseli(-ot, tt*a) - besseli(ot, tt*a)) + else: + return ot*(Pow(a, ot)*besseli(-ot, tt*a) - z*Pow(a, -ot)*besseli(ot, tt*a)) + + def _eval_rewrite_as_hyper(self, z, **kwargs): + pf1 = S.One / (3**Rational(2, 3)*gamma(Rational(2, 3))) + pf2 = z / (root(3, 3)*gamma(Rational(1, 3))) + return pf1 * hyper([], [Rational(2, 3)], z**3/9) - pf2 * hyper([], [Rational(4, 3)], z**3/9) + + def _eval_expand_func(self, **hints): + arg = self.args[0] + symbs = arg.free_symbols + + if len(symbs) == 1: + z = symbs.pop() + c = Wild("c", exclude=[z]) + d = Wild("d", exclude=[z]) + m = Wild("m", exclude=[z]) + n = Wild("n", exclude=[z]) + M = arg.match(c*(d*z**n)**m) + if M is not None: + m = M[m] + # The transformation is given by 03.05.16.0001.01 + # https://functions.wolfram.com/Bessel-TypeFunctions/AiryAi/16/01/01/0001/ + if (3*m).is_integer: + c = M[c] + d = M[d] + n = M[n] + pf = (d * z**n)**m / (d**m * z**(m*n)) + newarg = c * d**m * z**(m*n) + return S.Half * ((pf + S.One)*airyai(newarg) - (pf - S.One)/sqrt(3)*airybi(newarg)) + + +class airybi(AiryBase): + r""" + The Airy function $\operatorname{Bi}$ of the second kind. + + Explanation + =========== + + The Airy function $\operatorname{Bi}(z)$ is defined to be the function + satisfying Airy's differential equation + + .. math:: + \frac{\mathrm{d}^2 w(z)}{\mathrm{d}z^2} - z w(z) = 0. + + Equivalently, for real $z$ + + .. math:: + \operatorname{Bi}(z) := \frac{1}{\pi} + \int_0^\infty + \exp\left(-\frac{t^3}{3} + z t\right) + + \sin\left(\frac{t^3}{3} + z t\right) \mathrm{d}t. + + Examples + ======== + + Create an Airy function object: + + >>> from sympy import airybi + >>> from sympy.abc import z + + >>> airybi(z) + airybi(z) + + Several special values are known: + + >>> airybi(0) + 3**(5/6)/(3*gamma(2/3)) + >>> from sympy import oo + >>> airybi(oo) + oo + >>> airybi(-oo) + 0 + + The Airy function obeys the mirror symmetry: + + >>> from sympy import conjugate + >>> conjugate(airybi(z)) + airybi(conjugate(z)) + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(airybi(z), z) + airybiprime(z) + >>> diff(airybi(z), z, 2) + z*airybi(z) + + Series expansion is also supported: + + >>> from sympy import series + >>> series(airybi(z), z, 0, 3) + 3**(1/3)*gamma(1/3)/(2*pi) + 3**(2/3)*z*gamma(2/3)/(2*pi) + O(z**3) + + We can numerically evaluate the Airy function to arbitrary precision + on the whole complex plane: + + >>> airybi(-2).evalf(50) + -0.41230258795639848808323405461146104203453483447240 + + Rewrite $\operatorname{Bi}(z)$ in terms of hypergeometric functions: + + >>> from sympy import hyper + >>> airybi(z).rewrite(hyper) + 3**(1/6)*z*hyper((), (4/3,), z**3/9)/gamma(1/3) + 3**(5/6)*hyper((), (2/3,), z**3/9)/(3*gamma(2/3)) + + See Also + ======== + + airyai: Airy function of the first kind. + airyaiprime: Derivative of the Airy function of the first kind. + airybiprime: Derivative of the Airy function of the second kind. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Airy_function + .. [2] https://dlmf.nist.gov/9 + .. [3] https://encyclopediaofmath.org/wiki/Airy_functions + .. [4] https://mathworld.wolfram.com/AiryFunctions.html + + """ + + nargs = 1 + unbranched = True + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Infinity + elif arg is S.NegativeInfinity: + return S.Zero + elif arg.is_zero: + return S.One / (3**Rational(1, 6) * gamma(Rational(2, 3))) + + if arg.is_zero: + return S.One / (3**Rational(1, 6) * gamma(Rational(2, 3))) + + def fdiff(self, argindex=1): + if argindex == 1: + return airybiprime(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) > 1: + p = previous_terms[-1] + return (cbrt(3)*x * Abs(sin(Rational(2, 3)*pi*(n + S.One))) * factorial((n - S.One)/S(3)) / + ((n + S.One) * Abs(cos(Rational(2, 3)*pi*(n + S.Half))) * factorial((n - 2)/S(3))) * p) + else: + return (S.One/(root(3, 6)*pi) * gamma((n + S.One)/S(3)) * Abs(sin(Rational(2, 3)*pi*(n + S.One))) / + factorial(n) * (cbrt(3)*x)**n) + + def _eval_rewrite_as_besselj(self, z, **kwargs): + ot = Rational(1, 3) + tt = Rational(2, 3) + a = Pow(-z, Rational(3, 2)) + if re(z).is_negative: + return sqrt(-z/3) * (besselj(-ot, tt*a) - besselj(ot, tt*a)) + + def _eval_rewrite_as_besseli(self, z, **kwargs): + ot = Rational(1, 3) + tt = Rational(2, 3) + a = Pow(z, Rational(3, 2)) + if re(z).is_positive: + return sqrt(z)/sqrt(3) * (besseli(-ot, tt*a) + besseli(ot, tt*a)) + else: + b = Pow(a, ot) + c = Pow(a, -ot) + return sqrt(ot)*(b*besseli(-ot, tt*a) + z*c*besseli(ot, tt*a)) + + def _eval_rewrite_as_hyper(self, z, **kwargs): + pf1 = S.One / (root(3, 6)*gamma(Rational(2, 3))) + pf2 = z*root(3, 6) / gamma(Rational(1, 3)) + return pf1 * hyper([], [Rational(2, 3)], z**3/9) + pf2 * hyper([], [Rational(4, 3)], z**3/9) + + def _eval_expand_func(self, **hints): + arg = self.args[0] + symbs = arg.free_symbols + + if len(symbs) == 1: + z = symbs.pop() + c = Wild("c", exclude=[z]) + d = Wild("d", exclude=[z]) + m = Wild("m", exclude=[z]) + n = Wild("n", exclude=[z]) + M = arg.match(c*(d*z**n)**m) + if M is not None: + m = M[m] + # The transformation is given by 03.06.16.0001.01 + # https://functions.wolfram.com/Bessel-TypeFunctions/AiryBi/16/01/01/0001/ + if (3*m).is_integer: + c = M[c] + d = M[d] + n = M[n] + pf = (d * z**n)**m / (d**m * z**(m*n)) + newarg = c * d**m * z**(m*n) + return S.Half * (sqrt(3)*(S.One - pf)*airyai(newarg) + (S.One + pf)*airybi(newarg)) + + +class airyaiprime(AiryBase): + r""" + The derivative $\operatorname{Ai}^\prime$ of the Airy function of the first + kind. + + Explanation + =========== + + The Airy function $\operatorname{Ai}^\prime(z)$ is defined to be the + function + + .. math:: + \operatorname{Ai}^\prime(z) := \frac{\mathrm{d} \operatorname{Ai}(z)}{\mathrm{d} z}. + + Examples + ======== + + Create an Airy function object: + + >>> from sympy import airyaiprime + >>> from sympy.abc import z + + >>> airyaiprime(z) + airyaiprime(z) + + Several special values are known: + + >>> airyaiprime(0) + -3**(2/3)/(3*gamma(1/3)) + >>> from sympy import oo + >>> airyaiprime(oo) + 0 + + The Airy function obeys the mirror symmetry: + + >>> from sympy import conjugate + >>> conjugate(airyaiprime(z)) + airyaiprime(conjugate(z)) + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(airyaiprime(z), z) + z*airyai(z) + >>> diff(airyaiprime(z), z, 2) + z*airyaiprime(z) + airyai(z) + + Series expansion is also supported: + + >>> from sympy import series + >>> series(airyaiprime(z), z, 0, 3) + -3**(2/3)/(3*gamma(1/3)) + 3**(1/3)*z**2/(6*gamma(2/3)) + O(z**3) + + We can numerically evaluate the Airy function to arbitrary precision + on the whole complex plane: + + >>> airyaiprime(-2).evalf(50) + 0.61825902074169104140626429133247528291577794512415 + + Rewrite $\operatorname{Ai}^\prime(z)$ in terms of hypergeometric functions: + + >>> from sympy import hyper + >>> airyaiprime(z).rewrite(hyper) + 3**(1/3)*z**2*hyper((), (5/3,), z**3/9)/(6*gamma(2/3)) - 3**(2/3)*hyper((), (1/3,), z**3/9)/(3*gamma(1/3)) + + See Also + ======== + + airyai: Airy function of the first kind. + airybi: Airy function of the second kind. + airybiprime: Derivative of the Airy function of the second kind. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Airy_function + .. [2] https://dlmf.nist.gov/9 + .. [3] https://encyclopediaofmath.org/wiki/Airy_functions + .. [4] https://mathworld.wolfram.com/AiryFunctions.html + + """ + + nargs = 1 + unbranched = True + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Zero + + if arg.is_zero: + return S.NegativeOne / (3**Rational(1, 3) * gamma(Rational(1, 3))) + + def fdiff(self, argindex=1): + if argindex == 1: + return self.args[0]*airyai(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_evalf(self, prec): + z = self.args[0]._to_mpmath(prec) + with workprec(prec): + res = mp.airyai(z, derivative=1) + return Expr._from_mpmath(res, prec) + + def _eval_rewrite_as_besselj(self, z, **kwargs): + tt = Rational(2, 3) + a = Pow(-z, Rational(3, 2)) + if re(z).is_negative: + return z/3 * (besselj(-tt, tt*a) - besselj(tt, tt*a)) + + def _eval_rewrite_as_besseli(self, z, **kwargs): + ot = Rational(1, 3) + tt = Rational(2, 3) + a = tt * Pow(z, Rational(3, 2)) + if re(z).is_positive: + return z/3 * (besseli(tt, a) - besseli(-tt, a)) + else: + a = Pow(z, Rational(3, 2)) + b = Pow(a, tt) + c = Pow(a, -tt) + return ot * (z**2*c*besseli(tt, tt*a) - b*besseli(-ot, tt*a)) + + def _eval_rewrite_as_hyper(self, z, **kwargs): + pf1 = z**2 / (2*3**Rational(2, 3)*gamma(Rational(2, 3))) + pf2 = 1 / (root(3, 3)*gamma(Rational(1, 3))) + return pf1 * hyper([], [Rational(5, 3)], z**3/9) - pf2 * hyper([], [Rational(1, 3)], z**3/9) + + def _eval_expand_func(self, **hints): + arg = self.args[0] + symbs = arg.free_symbols + + if len(symbs) == 1: + z = symbs.pop() + c = Wild("c", exclude=[z]) + d = Wild("d", exclude=[z]) + m = Wild("m", exclude=[z]) + n = Wild("n", exclude=[z]) + M = arg.match(c*(d*z**n)**m) + if M is not None: + m = M[m] + # The transformation is in principle + # given by 03.07.16.0001.01 but note + # that there is an error in this formula. + # https://functions.wolfram.com/Bessel-TypeFunctions/AiryAiPrime/16/01/01/0001/ + if (3*m).is_integer: + c = M[c] + d = M[d] + n = M[n] + pf = (d**m * z**(n*m)) / (d * z**n)**m + newarg = c * d**m * z**(n*m) + return S.Half * ((pf + S.One)*airyaiprime(newarg) + (pf - S.One)/sqrt(3)*airybiprime(newarg)) + + +class airybiprime(AiryBase): + r""" + The derivative $\operatorname{Bi}^\prime$ of the Airy function of the first + kind. + + Explanation + =========== + + The Airy function $\operatorname{Bi}^\prime(z)$ is defined to be the + function + + .. math:: + \operatorname{Bi}^\prime(z) := \frac{\mathrm{d} \operatorname{Bi}(z)}{\mathrm{d} z}. + + Examples + ======== + + Create an Airy function object: + + >>> from sympy import airybiprime + >>> from sympy.abc import z + + >>> airybiprime(z) + airybiprime(z) + + Several special values are known: + + >>> airybiprime(0) + 3**(1/6)/gamma(1/3) + >>> from sympy import oo + >>> airybiprime(oo) + oo + >>> airybiprime(-oo) + 0 + + The Airy function obeys the mirror symmetry: + + >>> from sympy import conjugate + >>> conjugate(airybiprime(z)) + airybiprime(conjugate(z)) + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(airybiprime(z), z) + z*airybi(z) + >>> diff(airybiprime(z), z, 2) + z*airybiprime(z) + airybi(z) + + Series expansion is also supported: + + >>> from sympy import series + >>> series(airybiprime(z), z, 0, 3) + 3**(1/6)/gamma(1/3) + 3**(5/6)*z**2/(6*gamma(2/3)) + O(z**3) + + We can numerically evaluate the Airy function to arbitrary precision + on the whole complex plane: + + >>> airybiprime(-2).evalf(50) + 0.27879516692116952268509756941098324140300059345163 + + Rewrite $\operatorname{Bi}^\prime(z)$ in terms of hypergeometric functions: + + >>> from sympy import hyper + >>> airybiprime(z).rewrite(hyper) + 3**(5/6)*z**2*hyper((), (5/3,), z**3/9)/(6*gamma(2/3)) + 3**(1/6)*hyper((), (1/3,), z**3/9)/gamma(1/3) + + See Also + ======== + + airyai: Airy function of the first kind. + airybi: Airy function of the second kind. + airyaiprime: Derivative of the Airy function of the first kind. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Airy_function + .. [2] https://dlmf.nist.gov/9 + .. [3] https://encyclopediaofmath.org/wiki/Airy_functions + .. [4] https://mathworld.wolfram.com/AiryFunctions.html + + """ + + nargs = 1 + unbranched = True + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Infinity + elif arg is S.NegativeInfinity: + return S.Zero + elif arg.is_zero: + return 3**Rational(1, 6) / gamma(Rational(1, 3)) + + if arg.is_zero: + return 3**Rational(1, 6) / gamma(Rational(1, 3)) + + + def fdiff(self, argindex=1): + if argindex == 1: + return self.args[0]*airybi(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_evalf(self, prec): + z = self.args[0]._to_mpmath(prec) + with workprec(prec): + res = mp.airybi(z, derivative=1) + return Expr._from_mpmath(res, prec) + + def _eval_rewrite_as_besselj(self, z, **kwargs): + tt = Rational(2, 3) + a = tt * Pow(-z, Rational(3, 2)) + if re(z).is_negative: + return -z/sqrt(3) * (besselj(-tt, a) + besselj(tt, a)) + + def _eval_rewrite_as_besseli(self, z, **kwargs): + ot = Rational(1, 3) + tt = Rational(2, 3) + a = tt * Pow(z, Rational(3, 2)) + if re(z).is_positive: + return z/sqrt(3) * (besseli(-tt, a) + besseli(tt, a)) + else: + a = Pow(z, Rational(3, 2)) + b = Pow(a, tt) + c = Pow(a, -tt) + return sqrt(ot) * (b*besseli(-tt, tt*a) + z**2*c*besseli(tt, tt*a)) + + def _eval_rewrite_as_hyper(self, z, **kwargs): + pf1 = z**2 / (2*root(3, 6)*gamma(Rational(2, 3))) + pf2 = root(3, 6) / gamma(Rational(1, 3)) + return pf1 * hyper([], [Rational(5, 3)], z**3/9) + pf2 * hyper([], [Rational(1, 3)], z**3/9) + + def _eval_expand_func(self, **hints): + arg = self.args[0] + symbs = arg.free_symbols + + if len(symbs) == 1: + z = symbs.pop() + c = Wild("c", exclude=[z]) + d = Wild("d", exclude=[z]) + m = Wild("m", exclude=[z]) + n = Wild("n", exclude=[z]) + M = arg.match(c*(d*z**n)**m) + if M is not None: + m = M[m] + # The transformation is in principle + # given by 03.08.16.0001.01 but note + # that there is an error in this formula. + # https://functions.wolfram.com/Bessel-TypeFunctions/AiryBiPrime/16/01/01/0001/ + if (3*m).is_integer: + c = M[c] + d = M[d] + n = M[n] + pf = (d**m * z**(n*m)) / (d * z**n)**m + newarg = c * d**m * z**(n*m) + return S.Half * (sqrt(3)*(pf - S.One)*airyaiprime(newarg) + (pf + S.One)*airybiprime(newarg)) + + +class marcumq(DefinedFunction): + r""" + The Marcum Q-function. + + Explanation + =========== + + The Marcum Q-function is defined by the meromorphic continuation of + + .. math:: + Q_m(a, b) = a^{- m + 1} \int_{b}^{\infty} x^{m} e^{- \frac{a^{2}}{2} - \frac{x^{2}}{2}} I_{m - 1}\left(a x\right)\, dx + + Examples + ======== + + >>> from sympy import marcumq + >>> from sympy.abc import m, a, b + >>> marcumq(m, a, b) + marcumq(m, a, b) + + Special values: + + >>> marcumq(m, 0, b) + uppergamma(m, b**2/2)/gamma(m) + >>> marcumq(0, 0, 0) + 0 + >>> marcumq(0, a, 0) + 1 - exp(-a**2/2) + >>> marcumq(1, a, a) + 1/2 + exp(-a**2)*besseli(0, a**2)/2 + >>> marcumq(2, a, a) + 1/2 + exp(-a**2)*besseli(0, a**2)/2 + exp(-a**2)*besseli(1, a**2) + + Differentiation with respect to $a$ and $b$ is supported: + + >>> from sympy import diff + >>> diff(marcumq(m, a, b), a) + a*(-marcumq(m, a, b) + marcumq(m + 1, a, b)) + >>> diff(marcumq(m, a, b), b) + -a**(1 - m)*b**m*exp(-a**2/2 - b**2/2)*besseli(m - 1, a*b) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Marcum_Q-function + .. [2] https://mathworld.wolfram.com/MarcumQ-Function.html + + """ + + @classmethod + def eval(cls, m, a, b): + if a is S.Zero: + if m is S.Zero and b is S.Zero: + return S.Zero + return uppergamma(m, b**2 * S.Half) / gamma(m) + + if m is S.Zero and b is S.Zero: + return 1 - 1 / exp(a**2 * S.Half) + + if a == b: + if m is S.One: + return (1 + exp(-a**2) * besseli(0, a**2))*S.Half + if m == 2: + return S.Half + S.Half * exp(-a**2) * besseli(0, a**2) + exp(-a**2) * besseli(1, a**2) + + if a.is_zero: + if m.is_zero and b.is_zero: + return S.Zero + return uppergamma(m, b**2*S.Half) / gamma(m) + + if m.is_zero and b.is_zero: + return 1 - 1 / exp(a**2*S.Half) + + def fdiff(self, argindex=2): + m, a, b = self.args + if argindex == 2: + return a * (-marcumq(m, a, b) + marcumq(1+m, a, b)) + elif argindex == 3: + return (-b**m / a**(m-1)) * exp(-(a**2 + b**2)/2) * besseli(m-1, a*b) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Integral(self, m, a, b, **kwargs): + from sympy.integrals.integrals import Integral + x = kwargs.get('x', Dummy(uniquely_named_symbol('x').name)) + return a ** (1 - m) * \ + Integral(x**m * exp(-(x**2 + a**2)/2) * besseli(m-1, a*x), [x, b, S.Infinity]) + + def _eval_rewrite_as_Sum(self, m, a, b, **kwargs): + from sympy.concrete.summations import Sum + k = kwargs.get('k', Dummy('k')) + return exp(-(a**2 + b**2) / 2) * Sum((a/b)**k * besseli(k, a*b), [k, 1-m, S.Infinity]) + + def _eval_rewrite_as_besseli(self, m, a, b, **kwargs): + if a == b: + if m == 1: + return (1 + exp(-a**2) * besseli(0, a**2)) / 2 + if m.is_Integer and m >= 2: + s = sum(besseli(i, a**2) for i in range(1, m)) + return S.Half + exp(-a**2) * besseli(0, a**2) / 2 + exp(-a**2) * s + + def _eval_is_zero(self): + if all(arg.is_zero for arg in self.args): + return True + +class _besseli(DefinedFunction): + """ + Helper function to make the $\\mathrm{besseli}(nu, z)$ + function tractable for the Gruntz algorithm. + + """ + + def _eval_aseries(self, n, args0, x, logx): + from sympy.functions.combinatorial.factorials import RisingFactorial + from sympy.series.order import Order + point = args0[1] + + if point in [S.Infinity, S.NegativeInfinity]: + nu, z = self.args + l = [((RisingFactorial(Rational(2*nu - 1, 2), k)*RisingFactorial( + Rational(2*nu + 1, 2), k))/((2)**(k)*z**(Rational(2*k + 1, 2))*factorial(k))) for k in range(n)] + return sqrt(pi/(2))*(Add(*l)) + Order(1/z**(Rational(2*n + 1, 2)), x) + + return super()._eval_aseries(n, args0, x, logx) + + def _eval_rewrite_as_intractable(self, nu, z, **kwargs): + return exp(-z)*besseli(nu, z) + + def _eval_nseries(self, x, n, logx, cdir=0): + x0 = self.args[0].limit(x, 0) + if x0.is_zero: + f = self._eval_rewrite_as_intractable(*self.args) + return f._eval_nseries(x, n, logx) + return super()._eval_nseries(x, n, logx) + + +class _besselk(DefinedFunction): + """ + Helper function to make the $\\mathrm{besselk}(nu, z)$ + function tractable for the Gruntz algorithm. + + """ + + def _eval_aseries(self, n, args0, x, logx): + from sympy.functions.combinatorial.factorials import RisingFactorial + from sympy.series.order import Order + point = args0[1] + + if point in [S.Infinity, S.NegativeInfinity]: + nu, z = self.args + l = [((RisingFactorial(Rational(2*nu - 1, 2), k)*RisingFactorial( + Rational(2*nu + 1, 2), k))/((-2)**(k)*z**(Rational(2*k + 1, 2))*factorial(k))) for k in range(n)] + return sqrt(pi/(2))*(Add(*l)) + Order(1/z**(Rational(2*n + 1, 2)), x) + + return super()._eval_aseries(n, args0, x, logx) + + def _eval_rewrite_as_intractable(self,nu, z, **kwargs): + return exp(z)*besselk(nu, z) + + def _eval_nseries(self, x, n, logx, cdir=0): + x0 = self.args[0].limit(x, 0) + if x0.is_zero: + f = self._eval_rewrite_as_intractable(*self.args) + return f._eval_nseries(x, n, logx) + return super()._eval_nseries(x, n, logx) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/beta_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/beta_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..337ae6c71fe5a38cc0fcd819e9d489ebbbd1946b --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/beta_functions.py @@ -0,0 +1,389 @@ +from sympy.core import S +from sympy.core.function import DefinedFunction, ArgumentIndexError +from sympy.core.symbol import Dummy, uniquely_named_symbol +from sympy.functions.special.gamma_functions import gamma, digamma +from sympy.functions.combinatorial.numbers import catalan +from sympy.functions.elementary.complexes import conjugate + +# See mpmath #569 and SymPy #20569 +def betainc_mpmath_fix(a, b, x1, x2, reg=0): + from mpmath import betainc, mpf + if x1 == x2: + return mpf(0) + else: + return betainc(a, b, x1, x2, reg) + +############################################################################### +############################ COMPLETE BETA FUNCTION ########################## +############################################################################### + +class beta(DefinedFunction): + r""" + The beta integral is called the Eulerian integral of the first kind by + Legendre: + + .. math:: + \mathrm{B}(x,y) \int^{1}_{0} t^{x-1} (1-t)^{y-1} \mathrm{d}t. + + Explanation + =========== + + The Beta function or Euler's first integral is closely associated + with the gamma function. The Beta function is often used in probability + theory and mathematical statistics. It satisfies properties like: + + .. math:: + \mathrm{B}(a,1) = \frac{1}{a} \\ + \mathrm{B}(a,b) = \mathrm{B}(b,a) \\ + \mathrm{B}(a,b) = \frac{\Gamma(a) \Gamma(b)}{\Gamma(a+b)} + + Therefore for integral values of $a$ and $b$: + + .. math:: + \mathrm{B} = \frac{(a-1)! (b-1)!}{(a+b-1)!} + + A special case of the Beta function when `x = y` is the + Central Beta function. It satisfies properties like: + + .. math:: + \mathrm{B}(x) = 2^{1 - 2x}\mathrm{B}(x, \frac{1}{2}) + \mathrm{B}(x) = 2^{1 - 2x} cos(\pi x) \mathrm{B}(\frac{1}{2} - x, x) + \mathrm{B}(x) = \int_{0}^{1} \frac{t^x}{(1 + t)^{2x}} dt + \mathrm{B}(x) = \frac{2}{x} \prod_{n = 1}^{\infty} \frac{n(n + 2x)}{(n + x)^2} + + Examples + ======== + + >>> from sympy import I, pi + >>> from sympy.abc import x, y + + The Beta function obeys the mirror symmetry: + + >>> from sympy import beta, conjugate + >>> conjugate(beta(x, y)) + beta(conjugate(x), conjugate(y)) + + Differentiation with respect to both $x$ and $y$ is supported: + + >>> from sympy import beta, diff + >>> diff(beta(x, y), x) + (polygamma(0, x) - polygamma(0, x + y))*beta(x, y) + + >>> diff(beta(x, y), y) + (polygamma(0, y) - polygamma(0, x + y))*beta(x, y) + + >>> diff(beta(x), x) + 2*(polygamma(0, x) - polygamma(0, 2*x))*beta(x, x) + + We can numerically evaluate the Beta function to + arbitrary precision for any complex numbers x and y: + + >>> from sympy import beta + >>> beta(pi).evalf(40) + 0.02671848900111377452242355235388489324562 + + >>> beta(1 + I).evalf(20) + -0.2112723729365330143 - 0.7655283165378005676*I + + See Also + ======== + + gamma: Gamma function. + uppergamma: Upper incomplete gamma function. + lowergamma: Lower incomplete gamma function. + polygamma: Polygamma function. + loggamma: Log Gamma function. + digamma: Digamma function. + trigamma: Trigamma function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Beta_function + .. [2] https://mathworld.wolfram.com/BetaFunction.html + .. [3] https://dlmf.nist.gov/5.12 + + """ + unbranched = True + + def fdiff(self, argindex): + x, y = self.args + if argindex == 1: + # Diff wrt x + return beta(x, y)*(digamma(x) - digamma(x + y)) + elif argindex == 2: + # Diff wrt y + return beta(x, y)*(digamma(y) - digamma(x + y)) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, x, y=None): + if y is None: + return beta(x, x) + if x.is_Number and y.is_Number: + return beta(x, y, evaluate=False).doit() + + def doit(self, **hints): + x = xold = self.args[0] + # Deal with unevaluated single argument beta + single_argument = len(self.args) == 1 + y = yold = self.args[0] if single_argument else self.args[1] + if hints.get('deep', True): + x = x.doit(**hints) + y = y.doit(**hints) + if y.is_zero or x.is_zero: + return S.ComplexInfinity + if y is S.One: + return 1/x + if x is S.One: + return 1/y + if y == x + 1: + return 1/(x*y*catalan(x)) + s = x + y + if (s.is_integer and s.is_negative and x.is_integer is False and + y.is_integer is False): + return S.Zero + if x == xold and y == yold and not single_argument: + return self + return beta(x, y) + + def _eval_expand_func(self, **hints): + x, y = self.args + return gamma(x)*gamma(y) / gamma(x + y) + + def _eval_is_real(self): + return self.args[0].is_real and self.args[1].is_real + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate(), self.args[1].conjugate()) + + def _eval_rewrite_as_gamma(self, x, y, piecewise=True, **kwargs): + return self._eval_expand_func(**kwargs) + + def _eval_rewrite_as_Integral(self, x, y, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', [x, y]).name) + return Integral(t**(x - 1)*(1 - t)**(y - 1), (t, 0, 1)) + +############################################################################### +########################## INCOMPLETE BETA FUNCTION ########################### +############################################################################### + +class betainc(DefinedFunction): + r""" + The Generalized Incomplete Beta function is defined as + + .. math:: + \mathrm{B}_{(x_1, x_2)}(a, b) = \int_{x_1}^{x_2} t^{a - 1} (1 - t)^{b - 1} dt + + The Incomplete Beta function is a special case + of the Generalized Incomplete Beta function : + + .. math:: \mathrm{B}_z (a, b) = \mathrm{B}_{(0, z)}(a, b) + + The Incomplete Beta function satisfies : + + .. math:: \mathrm{B}_z (a, b) = (-1)^a \mathrm{B}_{\frac{z}{z - 1}} (a, 1 - a - b) + + The Beta function is a special case of the Incomplete Beta function : + + .. math:: \mathrm{B}(a, b) = \mathrm{B}_{1}(a, b) + + Examples + ======== + + >>> from sympy import betainc, symbols, conjugate + >>> a, b, x, x1, x2 = symbols('a b x x1 x2') + + The Generalized Incomplete Beta function is given by: + + >>> betainc(a, b, x1, x2) + betainc(a, b, x1, x2) + + The Incomplete Beta function can be obtained as follows: + + >>> betainc(a, b, 0, x) + betainc(a, b, 0, x) + + The Incomplete Beta function obeys the mirror symmetry: + + >>> conjugate(betainc(a, b, x1, x2)) + betainc(conjugate(a), conjugate(b), conjugate(x1), conjugate(x2)) + + We can numerically evaluate the Incomplete Beta function to + arbitrary precision for any complex numbers a, b, x1 and x2: + + >>> from sympy import betainc, I + >>> betainc(2, 3, 4, 5).evalf(10) + 56.08333333 + >>> betainc(0.75, 1 - 4*I, 0, 2 + 3*I).evalf(25) + 0.2241657956955709603655887 + 0.3619619242700451992411724*I + + The Generalized Incomplete Beta function can be expressed + in terms of the Generalized Hypergeometric function. + + >>> from sympy import hyper + >>> betainc(a, b, x1, x2).rewrite(hyper) + (-x1**a*hyper((a, 1 - b), (a + 1,), x1) + x2**a*hyper((a, 1 - b), (a + 1,), x2))/a + + See Also + ======== + + beta: Beta function + hyper: Generalized Hypergeometric function + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Beta_function#Incomplete_beta_function + .. [2] https://dlmf.nist.gov/8.17 + .. [3] https://functions.wolfram.com/GammaBetaErf/Beta4/ + .. [4] https://functions.wolfram.com/GammaBetaErf/BetaRegularized4/02/ + + """ + nargs = 4 + unbranched = True + + def fdiff(self, argindex): + a, b, x1, x2 = self.args + if argindex == 3: + # Diff wrt x1 + return -(1 - x1)**(b - 1)*x1**(a - 1) + elif argindex == 4: + # Diff wrt x2 + return (1 - x2)**(b - 1)*x2**(a - 1) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_mpmath(self): + return betainc_mpmath_fix, self.args + + def _eval_is_real(self): + if all(arg.is_real for arg in self.args): + return True + + def _eval_conjugate(self): + return self.func(*map(conjugate, self.args)) + + def _eval_rewrite_as_Integral(self, a, b, x1, x2, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', [a, b, x1, x2]).name) + return Integral(t**(a - 1)*(1 - t)**(b - 1), (t, x1, x2)) + + def _eval_rewrite_as_hyper(self, a, b, x1, x2, **kwargs): + from sympy.functions.special.hyper import hyper + return (x2**a * hyper((a, 1 - b), (a + 1,), x2) - x1**a * hyper((a, 1 - b), (a + 1,), x1)) / a + +############################################################################### +#################### REGULARIZED INCOMPLETE BETA FUNCTION ##################### +############################################################################### + +class betainc_regularized(DefinedFunction): + r""" + The Generalized Regularized Incomplete Beta function is given by + + .. math:: + \mathrm{I}_{(x_1, x_2)}(a, b) = \frac{\mathrm{B}_{(x_1, x_2)}(a, b)}{\mathrm{B}(a, b)} + + The Regularized Incomplete Beta function is a special case + of the Generalized Regularized Incomplete Beta function : + + .. math:: \mathrm{I}_z (a, b) = \mathrm{I}_{(0, z)}(a, b) + + The Regularized Incomplete Beta function is the cumulative distribution + function of the beta distribution. + + Examples + ======== + + >>> from sympy import betainc_regularized, symbols, conjugate + >>> a, b, x, x1, x2 = symbols('a b x x1 x2') + + The Generalized Regularized Incomplete Beta + function is given by: + + >>> betainc_regularized(a, b, x1, x2) + betainc_regularized(a, b, x1, x2) + + The Regularized Incomplete Beta function + can be obtained as follows: + + >>> betainc_regularized(a, b, 0, x) + betainc_regularized(a, b, 0, x) + + The Regularized Incomplete Beta function + obeys the mirror symmetry: + + >>> conjugate(betainc_regularized(a, b, x1, x2)) + betainc_regularized(conjugate(a), conjugate(b), conjugate(x1), conjugate(x2)) + + We can numerically evaluate the Regularized Incomplete Beta function + to arbitrary precision for any complex numbers a, b, x1 and x2: + + >>> from sympy import betainc_regularized, pi, E + >>> betainc_regularized(1, 2, 0, 0.25).evalf(10) + 0.4375000000 + >>> betainc_regularized(pi, E, 0, 1).evalf(5) + 1.00000 + + The Generalized Regularized Incomplete Beta function can be + expressed in terms of the Generalized Hypergeometric function. + + >>> from sympy import hyper + >>> betainc_regularized(a, b, x1, x2).rewrite(hyper) + (-x1**a*hyper((a, 1 - b), (a + 1,), x1) + x2**a*hyper((a, 1 - b), (a + 1,), x2))/(a*beta(a, b)) + + See Also + ======== + + beta: Beta function + hyper: Generalized Hypergeometric function + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Beta_function#Incomplete_beta_function + .. [2] https://dlmf.nist.gov/8.17 + .. [3] https://functions.wolfram.com/GammaBetaErf/Beta4/ + .. [4] https://functions.wolfram.com/GammaBetaErf/BetaRegularized4/02/ + + """ + nargs = 4 + unbranched = True + + def __new__(cls, a, b, x1, x2): + return super().__new__(cls, a, b, x1, x2) + + def _eval_mpmath(self): + return betainc_mpmath_fix, (*self.args, S(1)) + + def fdiff(self, argindex): + a, b, x1, x2 = self.args + if argindex == 3: + # Diff wrt x1 + return -(1 - x1)**(b - 1)*x1**(a - 1) / beta(a, b) + elif argindex == 4: + # Diff wrt x2 + return (1 - x2)**(b - 1)*x2**(a - 1) / beta(a, b) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_is_real(self): + if all(arg.is_real for arg in self.args): + return True + + def _eval_conjugate(self): + return self.func(*map(conjugate, self.args)) + + def _eval_rewrite_as_Integral(self, a, b, x1, x2, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', [a, b, x1, x2]).name) + integrand = t**(a - 1)*(1 - t)**(b - 1) + expr = Integral(integrand, (t, x1, x2)) + return expr / Integral(integrand, (t, 0, 1)) + + def _eval_rewrite_as_hyper(self, a, b, x1, x2, **kwargs): + from sympy.functions.special.hyper import hyper + expr = (x2**a * hyper((a, 1 - b), (a + 1,), x2) - x1**a * hyper((a, 1 - b), (a + 1,), x1)) / a + return expr / beta(a, b) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/bsplines.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/bsplines.py new file mode 100644 index 0000000000000000000000000000000000000000..50c9141e841288aa02457c466fc6573f9a20d09f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/bsplines.py @@ -0,0 +1,348 @@ +from sympy.core import S, sympify +from sympy.core.symbol import (Dummy, symbols) +from sympy.functions import Piecewise, piecewise_fold +from sympy.logic.boolalg import And +from sympy.sets.sets import Interval + +from functools import lru_cache + + +def _ivl(cond, x): + """return the interval corresponding to the condition + + Conditions in spline's Piecewise give the range over + which an expression is valid like (lo <= x) & (x <= hi). + This function returns (lo, hi). + """ + if isinstance(cond, And) and len(cond.args) == 2: + a, b = cond.args + if a.lts == x: + a, b = b, a + return a.lts, b.gts + raise TypeError('unexpected cond type: %s' % cond) + + +def _add_splines(c, b1, d, b2, x): + """Construct c*b1 + d*b2.""" + + if S.Zero in (b1, c): + rv = piecewise_fold(d * b2) + elif S.Zero in (b2, d): + rv = piecewise_fold(c * b1) + else: + new_args = [] + # Just combining the Piecewise without any fancy optimization + p1 = piecewise_fold(c * b1) + p2 = piecewise_fold(d * b2) + + # Search all Piecewise arguments except (0, True) + p2args = list(p2.args[:-1]) + + # This merging algorithm assumes the conditions in + # p1 and p2 are sorted + for arg in p1.args[:-1]: + expr = arg.expr + cond = arg.cond + + lower = _ivl(cond, x)[0] + + # Check p2 for matching conditions that can be merged + for i, arg2 in enumerate(p2args): + expr2 = arg2.expr + cond2 = arg2.cond + + lower_2, upper_2 = _ivl(cond2, x) + if cond2 == cond: + # Conditions match, join expressions + expr += expr2 + # Remove matching element + del p2args[i] + # No need to check the rest + break + elif lower_2 < lower and upper_2 <= lower: + # Check if arg2 condition smaller than arg1, + # add to new_args by itself (no match expected + # in p1) + new_args.append(arg2) + del p2args[i] + break + + # Checked all, add expr and cond + new_args.append((expr, cond)) + + # Add remaining items from p2args + new_args.extend(p2args) + + # Add final (0, True) + new_args.append((0, True)) + + rv = Piecewise(*new_args, evaluate=False) + + return rv.expand() + + +@lru_cache(maxsize=128) +def bspline_basis(d, knots, n, x): + """ + The $n$-th B-spline at $x$ of degree $d$ with knots. + + Explanation + =========== + + B-Splines are piecewise polynomials of degree $d$. They are defined on a + set of knots, which is a sequence of integers or floats. + + Examples + ======== + + The 0th degree splines have a value of 1 on a single interval: + + >>> from sympy import bspline_basis + >>> from sympy.abc import x + >>> d = 0 + >>> knots = tuple(range(5)) + >>> bspline_basis(d, knots, 0, x) + Piecewise((1, (x >= 0) & (x <= 1)), (0, True)) + + For a given ``(d, knots)`` there are ``len(knots)-d-1`` B-splines + defined, that are indexed by ``n`` (starting at 0). + + Here is an example of a cubic B-spline: + + >>> bspline_basis(3, tuple(range(5)), 0, x) + Piecewise((x**3/6, (x >= 0) & (x <= 1)), + (-x**3/2 + 2*x**2 - 2*x + 2/3, + (x >= 1) & (x <= 2)), + (x**3/2 - 4*x**2 + 10*x - 22/3, + (x >= 2) & (x <= 3)), + (-x**3/6 + 2*x**2 - 8*x + 32/3, + (x >= 3) & (x <= 4)), + (0, True)) + + By repeating knot points, you can introduce discontinuities in the + B-splines and their derivatives: + + >>> d = 1 + >>> knots = (0, 0, 2, 3, 4) + >>> bspline_basis(d, knots, 0, x) + Piecewise((1 - x/2, (x >= 0) & (x <= 2)), (0, True)) + + It is quite time consuming to construct and evaluate B-splines. If + you need to evaluate a B-spline many times, it is best to lambdify them + first: + + >>> from sympy import lambdify + >>> d = 3 + >>> knots = tuple(range(10)) + >>> b0 = bspline_basis(d, knots, 0, x) + >>> f = lambdify(x, b0) + >>> y = f(0.5) + + Parameters + ========== + + d : integer + degree of bspline + + knots : list of integer values + list of knots points of bspline + + n : integer + $n$-th B-spline + + x : symbol + + See Also + ======== + + bspline_basis_set + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/B-spline + + """ + # make sure x has no assumptions so conditions don't evaluate + xvar = x + x = Dummy() + + knots = tuple(sympify(k) for k in knots) + d = int(d) + n = int(n) + n_knots = len(knots) + n_intervals = n_knots - 1 + if n + d + 1 > n_intervals: + raise ValueError("n + d + 1 must not exceed len(knots) - 1") + if d == 0: + result = Piecewise( + (S.One, Interval(knots[n], knots[n + 1]).contains(x)), (0, True) + ) + elif d > 0: + denom = knots[n + d + 1] - knots[n + 1] + if denom != S.Zero: + B = (knots[n + d + 1] - x) / denom + b2 = bspline_basis(d - 1, knots, n + 1, x) + else: + b2 = B = S.Zero + + denom = knots[n + d] - knots[n] + if denom != S.Zero: + A = (x - knots[n]) / denom + b1 = bspline_basis(d - 1, knots, n, x) + else: + b1 = A = S.Zero + + result = _add_splines(A, b1, B, b2, x) + else: + raise ValueError("degree must be non-negative: %r" % n) + + # return result with user-given x + return result.xreplace({x: xvar}) + + +def bspline_basis_set(d, knots, x): + """ + Return the ``len(knots)-d-1`` B-splines at *x* of degree *d* + with *knots*. + + Explanation + =========== + + This function returns a list of piecewise polynomials that are the + ``len(knots)-d-1`` B-splines of degree *d* for the given knots. + This function calls ``bspline_basis(d, knots, n, x)`` for different + values of *n*. + + Examples + ======== + + >>> from sympy import bspline_basis_set + >>> from sympy.abc import x + >>> d = 2 + >>> knots = range(5) + >>> splines = bspline_basis_set(d, knots, x) + >>> splines + [Piecewise((x**2/2, (x >= 0) & (x <= 1)), + (-x**2 + 3*x - 3/2, (x >= 1) & (x <= 2)), + (x**2/2 - 3*x + 9/2, (x >= 2) & (x <= 3)), + (0, True)), + Piecewise((x**2/2 - x + 1/2, (x >= 1) & (x <= 2)), + (-x**2 + 5*x - 11/2, (x >= 2) & (x <= 3)), + (x**2/2 - 4*x + 8, (x >= 3) & (x <= 4)), + (0, True))] + + Parameters + ========== + + d : integer + degree of bspline + + knots : list of integers + list of knots points of bspline + + x : symbol + + See Also + ======== + + bspline_basis + + """ + n_splines = len(knots) - d - 1 + return [bspline_basis(d, tuple(knots), i, x) for i in range(n_splines)] + + +def interpolating_spline(d, x, X, Y): + """ + Return spline of degree *d*, passing through the given *X* + and *Y* values. + + Explanation + =========== + + This function returns a piecewise function such that each part is + a polynomial of degree not greater than *d*. The value of *d* + must be 1 or greater and the values of *X* must be strictly + increasing. + + Examples + ======== + + >>> from sympy import interpolating_spline + >>> from sympy.abc import x + >>> interpolating_spline(1, x, [1, 2, 4, 7], [3, 6, 5, 7]) + Piecewise((3*x, (x >= 1) & (x <= 2)), + (7 - x/2, (x >= 2) & (x <= 4)), + (2*x/3 + 7/3, (x >= 4) & (x <= 7))) + >>> interpolating_spline(3, x, [-2, 0, 1, 3, 4], [4, 2, 1, 1, 3]) + Piecewise((7*x**3/117 + 7*x**2/117 - 131*x/117 + 2, (x >= -2) & (x <= 1)), + (10*x**3/117 - 2*x**2/117 - 122*x/117 + 77/39, (x >= 1) & (x <= 4))) + + Parameters + ========== + + d : integer + Degree of Bspline strictly greater than equal to one + + x : symbol + + X : list of strictly increasing real values + list of X coordinates through which the spline passes + + Y : list of real values + list of corresponding Y coordinates through which the spline passes + + See Also + ======== + + bspline_basis_set, interpolating_poly + + """ + from sympy.solvers.solveset import linsolve + from sympy.matrices.dense import Matrix + + # Input sanitization + d = sympify(d) + if not (d.is_Integer and d.is_positive): + raise ValueError("Spline degree must be a positive integer, not %s." % d) + if len(X) != len(Y): + raise ValueError("Number of X and Y coordinates must be the same.") + if len(X) < d + 1: + raise ValueError("Degree must be less than the number of control points.") + if not all(a < b for a, b in zip(X, X[1:])): + raise ValueError("The x-coordinates must be strictly increasing.") + X = [sympify(i) for i in X] + + # Evaluating knots value + if d.is_odd: + j = (d + 1) // 2 + interior_knots = X[j:-j] + else: + j = d // 2 + interior_knots = [ + (a + b)/2 for a, b in zip(X[j : -j - 1], X[j + 1 : -j]) + ] + + knots = [X[0]] * (d + 1) + list(interior_knots) + [X[-1]] * (d + 1) + + basis = bspline_basis_set(d, knots, x) + + A = [[b.subs(x, v) for b in basis] for v in X] + + coeff = linsolve((Matrix(A), Matrix(Y)), symbols("c0:{}".format(len(X)), cls=Dummy)) + coeff = list(coeff)[0] + intervals = {c for b in basis for (e, c) in b.args if c != True} + + # Sorting the intervals + # ival contains the end-points of each interval + intervals = sorted(intervals, key=lambda c: _ivl(c, x)) + + basis_dicts = [{c: e for (e, c) in b.args} for b in basis] + spline = [] + for i in intervals: + piece = sum( + [c * d.get(i, S.Zero) for (c, d) in zip(coeff, basis_dicts)], S.Zero + ) + spline.append((piece, i)) + return Piecewise(*spline) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/delta_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/delta_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..698d8c0c3ba5e68c2f084e83e7a9ec070ce83307 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/delta_functions.py @@ -0,0 +1,664 @@ +from sympy.core import S, diff +from sympy.core.function import DefinedFunction, ArgumentIndexError +from sympy.core.logic import fuzzy_not +from sympy.core.relational import Eq, Ne +from sympy.functions.elementary.complexes import im, sign +from sympy.functions.elementary.piecewise import Piecewise +from sympy.polys.polyerrors import PolynomialError +from sympy.polys.polyroots import roots +from sympy.utilities.misc import filldedent + + +############################################################################### +################################ DELTA FUNCTION ############################### +############################################################################### + + +class DiracDelta(DefinedFunction): + r""" + The DiracDelta function and its derivatives. + + Explanation + =========== + + DiracDelta is not an ordinary function. It can be rigorously defined either + as a distribution or as a measure. + + DiracDelta only makes sense in definite integrals, and in particular, + integrals of the form ``Integral(f(x)*DiracDelta(x - x0), (x, a, b))``, + where it equals ``f(x0)`` if ``a <= x0 <= b`` and ``0`` otherwise. Formally, + DiracDelta acts in some ways like a function that is ``0`` everywhere except + at ``0``, but in many ways it also does not. It can often be useful to treat + DiracDelta in formal ways, building up and manipulating expressions with + delta functions (which may eventually be integrated), but care must be taken + to not treat it as a real function. SymPy's ``oo`` is similar. It only + truly makes sense formally in certain contexts (such as integration limits), + but SymPy allows its use everywhere, and it tries to be consistent with + operations on it (like ``1/oo``), but it is easy to get into trouble and get + wrong results if ``oo`` is treated too much like a number. Similarly, if + DiracDelta is treated too much like a function, it is easy to get wrong or + nonsensical results. + + DiracDelta function has the following properties: + + 1) $\frac{d}{d x} \theta(x) = \delta(x)$ + 2) $\int_{-\infty}^\infty \delta(x - a)f(x)\, dx = f(a)$ and $\int_{a- + \epsilon}^{a+\epsilon} \delta(x - a)f(x)\, dx = f(a)$ + 3) $\delta(x) = 0$ for all $x \neq 0$ + 4) $\delta(g(x)) = \sum_i \frac{\delta(x - x_i)}{\|g'(x_i)\|}$ where $x_i$ + are the roots of $g$ + 5) $\delta(-x) = \delta(x)$ + + Derivatives of ``k``-th order of DiracDelta have the following properties: + + 6) $\delta(x, k) = 0$ for all $x \neq 0$ + 7) $\delta(-x, k) = -\delta(x, k)$ for odd $k$ + 8) $\delta(-x, k) = \delta(x, k)$ for even $k$ + + Examples + ======== + + >>> from sympy import DiracDelta, diff, pi + >>> from sympy.abc import x, y + + >>> DiracDelta(x) + DiracDelta(x) + >>> DiracDelta(1) + 0 + >>> DiracDelta(-1) + 0 + >>> DiracDelta(pi) + 0 + >>> DiracDelta(x - 4).subs(x, 4) + DiracDelta(0) + >>> diff(DiracDelta(x)) + DiracDelta(x, 1) + >>> diff(DiracDelta(x - 1), x, 2) + DiracDelta(x - 1, 2) + >>> diff(DiracDelta(x**2 - 1), x, 2) + 2*(2*x**2*DiracDelta(x**2 - 1, 2) + DiracDelta(x**2 - 1, 1)) + >>> DiracDelta(3*x).is_simple(x) + True + >>> DiracDelta(x**2).is_simple(x) + False + >>> DiracDelta((x**2 - 1)*y).expand(diracdelta=True, wrt=x) + DiracDelta(x - 1)/(2*Abs(y)) + DiracDelta(x + 1)/(2*Abs(y)) + + See Also + ======== + + Heaviside + sympy.simplify.simplify.simplify, is_simple + sympy.functions.special.tensor_functions.KroneckerDelta + + References + ========== + + .. [1] https://mathworld.wolfram.com/DeltaFunction.html + + """ + + is_real = True + + def fdiff(self, argindex=1): + """ + Returns the first derivative of a DiracDelta Function. + + Explanation + =========== + + The difference between ``diff()`` and ``fdiff()`` is: ``diff()`` is the + user-level function and ``fdiff()`` is an object method. ``fdiff()`` is + a convenience method available in the ``Function`` class. It returns + the derivative of the function without considering the chain rule. + ``diff(function, x)`` calls ``Function._eval_derivative`` which in turn + calls ``fdiff()`` internally to compute the derivative of the function. + + Examples + ======== + + >>> from sympy import DiracDelta, diff + >>> from sympy.abc import x + + >>> DiracDelta(x).fdiff() + DiracDelta(x, 1) + + >>> DiracDelta(x, 1).fdiff() + DiracDelta(x, 2) + + >>> DiracDelta(x**2 - 1).fdiff() + DiracDelta(x**2 - 1, 1) + + >>> diff(DiracDelta(x, 1)).fdiff() + DiracDelta(x, 3) + + Parameters + ========== + + argindex : integer + degree of derivative + + """ + if argindex == 1: + #I didn't know if there is a better way to handle default arguments + k = 0 + if len(self.args) > 1: + k = self.args[1] + return self.func(self.args[0], k + 1) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg, k=S.Zero): + """ + Returns a simplified form or a value of DiracDelta depending on the + argument passed by the DiracDelta object. + + Explanation + =========== + + The ``eval()`` method is automatically called when the ``DiracDelta`` + class is about to be instantiated and it returns either some simplified + instance or the unevaluated instance depending on the argument passed. + In other words, ``eval()`` method is not needed to be called explicitly, + it is being called and evaluated once the object is called. + + Examples + ======== + + >>> from sympy import DiracDelta, S + >>> from sympy.abc import x + + >>> DiracDelta(x) + DiracDelta(x) + + >>> DiracDelta(-x, 1) + -DiracDelta(x, 1) + + >>> DiracDelta(1) + 0 + + >>> DiracDelta(5, 1) + 0 + + >>> DiracDelta(0) + DiracDelta(0) + + >>> DiracDelta(-1) + 0 + + >>> DiracDelta(S.NaN) + nan + + >>> DiracDelta(x - 100).subs(x, 5) + 0 + + >>> DiracDelta(x - 100).subs(x, 100) + DiracDelta(0) + + Parameters + ========== + + k : integer + order of derivative + + arg : argument passed to DiracDelta + + """ + if not k.is_Integer or k.is_negative: + raise ValueError("Error: the second argument of DiracDelta must be \ + a non-negative integer, %s given instead." % (k,)) + if arg is S.NaN: + return S.NaN + if arg.is_nonzero: + return S.Zero + if fuzzy_not(im(arg).is_zero): + raise ValueError(filldedent(''' + Function defined only for Real Values. + Complex part: %s found in %s .''' % ( + repr(im(arg)), repr(arg)))) + c, nc = arg.args_cnc() + if c and c[0] is S.NegativeOne: + # keep this fast and simple instead of using + # could_extract_minus_sign + if k.is_odd: + return -cls(-arg, k) + elif k.is_even: + return cls(-arg, k) if k else cls(-arg) + elif k.is_zero: + return cls(arg, evaluate=False) + + def _eval_expand_diracdelta(self, **hints): + """ + Compute a simplified representation of the function using + property number 4. Pass ``wrt`` as a hint to expand the expression + with respect to a particular variable. + + Explanation + =========== + + ``wrt`` is: + + - a variable with respect to which a DiracDelta expression will + get expanded. + + Examples + ======== + + >>> from sympy import DiracDelta + >>> from sympy.abc import x, y + + >>> DiracDelta(x*y).expand(diracdelta=True, wrt=x) + DiracDelta(x)/Abs(y) + >>> DiracDelta(x*y).expand(diracdelta=True, wrt=y) + DiracDelta(y)/Abs(x) + + >>> DiracDelta(x**2 + x - 2).expand(diracdelta=True, wrt=x) + DiracDelta(x - 1)/3 + DiracDelta(x + 2)/3 + + See Also + ======== + + is_simple, Diracdelta + + """ + wrt = hints.get('wrt', None) + if wrt is None: + free = self.free_symbols + if len(free) == 1: + wrt = free.pop() + else: + raise TypeError(filldedent(''' + When there is more than 1 free symbol or variable in the expression, + the 'wrt' keyword is required as a hint to expand when using the + DiracDelta hint.''')) + + if not self.args[0].has(wrt) or (len(self.args) > 1 and self.args[1] != 0 ): + return self + try: + argroots = roots(self.args[0], wrt) + result = 0 + valid = True + darg = abs(diff(self.args[0], wrt)) + for r, m in argroots.items(): + if r.is_real is not False and m == 1: + result += self.func(wrt - r)/darg.subs(wrt, r) + else: + # don't handle non-real and if m != 1 then + # a polynomial will have a zero in the derivative (darg) + # at r + valid = False + break + if valid: + return result + except PolynomialError: + pass + return self + + def is_simple(self, x): + """ + Tells whether the argument(args[0]) of DiracDelta is a linear + expression in *x*. + + Examples + ======== + + >>> from sympy import DiracDelta, cos + >>> from sympy.abc import x, y + + >>> DiracDelta(x*y).is_simple(x) + True + >>> DiracDelta(x*y).is_simple(y) + True + + >>> DiracDelta(x**2 + x - 2).is_simple(x) + False + + >>> DiracDelta(cos(x)).is_simple(x) + False + + Parameters + ========== + + x : can be a symbol + + See Also + ======== + + sympy.simplify.simplify.simplify, DiracDelta + + """ + p = self.args[0].as_poly(x) + if p: + return p.degree() == 1 + return False + + def _eval_rewrite_as_Piecewise(self, *args, **kwargs): + """ + Represents DiracDelta in a piecewise form. + + Examples + ======== + + >>> from sympy import DiracDelta, Piecewise, Symbol + >>> x = Symbol('x') + + >>> DiracDelta(x).rewrite(Piecewise) + Piecewise((DiracDelta(0), Eq(x, 0)), (0, True)) + + >>> DiracDelta(x - 5).rewrite(Piecewise) + Piecewise((DiracDelta(0), Eq(x, 5)), (0, True)) + + >>> DiracDelta(x**2 - 5).rewrite(Piecewise) + Piecewise((DiracDelta(0), Eq(x**2, 5)), (0, True)) + + >>> DiracDelta(x - 5, 4).rewrite(Piecewise) + DiracDelta(x - 5, 4) + + """ + if len(args) == 1: + return Piecewise((DiracDelta(0), Eq(args[0], 0)), (0, True)) + + def _eval_rewrite_as_SingularityFunction(self, *args, **kwargs): + """ + Returns the DiracDelta expression written in the form of Singularity + Functions. + + """ + from sympy.solvers import solve + from sympy.functions.special.singularity_functions import SingularityFunction + if self == DiracDelta(0): + return SingularityFunction(0, 0, -1) + if self == DiracDelta(0, 1): + return SingularityFunction(0, 0, -2) + free = self.free_symbols + if len(free) == 1: + x = (free.pop()) + if len(args) == 1: + return SingularityFunction(x, solve(args[0], x)[0], -1) + return SingularityFunction(x, solve(args[0], x)[0], -args[1] - 1) + else: + # I don't know how to handle the case for DiracDelta expressions + # having arguments with more than one variable. + raise TypeError(filldedent(''' + rewrite(SingularityFunction) does not support + arguments with more that one variable.''')) + + +############################################################################### +############################## HEAVISIDE FUNCTION ############################# +############################################################################### + + +class Heaviside(DefinedFunction): + r""" + Heaviside step function. + + Explanation + =========== + + The Heaviside step function has the following properties: + + 1) $\frac{d}{d x} \theta(x) = \delta(x)$ + 2) $\theta(x) = \begin{cases} 0 & \text{for}\: x < 0 \\ \frac{1}{2} & + \text{for}\: x = 0 \\1 & \text{for}\: x > 0 \end{cases}$ + 3) $\frac{d}{d x} \max(x, 0) = \theta(x)$ + + Heaviside(x) is printed as $\theta(x)$ with the SymPy LaTeX printer. + + The value at 0 is set differently in different fields. SymPy uses 1/2, + which is a convention from electronics and signal processing, and is + consistent with solving improper integrals by Fourier transform and + convolution. + + To specify a different value of Heaviside at ``x=0``, a second argument + can be given. Using ``Heaviside(x, nan)`` gives an expression that will + evaluate to nan for x=0. + + .. versionchanged:: 1.9 ``Heaviside(0)`` now returns 1/2 (before: undefined) + + Examples + ======== + + >>> from sympy import Heaviside, nan + >>> from sympy.abc import x + >>> Heaviside(9) + 1 + >>> Heaviside(-9) + 0 + >>> Heaviside(0) + 1/2 + >>> Heaviside(0, nan) + nan + >>> (Heaviside(x) + 1).replace(Heaviside(x), Heaviside(x, 1)) + Heaviside(x, 1) + 1 + + See Also + ======== + + DiracDelta + + References + ========== + + .. [1] https://mathworld.wolfram.com/HeavisideStepFunction.html + .. [2] https://dlmf.nist.gov/1.16#iv + + """ + + is_real = True + + def fdiff(self, argindex=1): + """ + Returns the first derivative of a Heaviside Function. + + Examples + ======== + + >>> from sympy import Heaviside, diff + >>> from sympy.abc import x + + >>> Heaviside(x).fdiff() + DiracDelta(x) + + >>> Heaviside(x**2 - 1).fdiff() + DiracDelta(x**2 - 1) + + >>> diff(Heaviside(x)).fdiff() + DiracDelta(x, 1) + + Parameters + ========== + + argindex : integer + order of derivative + + """ + if argindex == 1: + return DiracDelta(self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + def __new__(cls, arg, H0=S.Half, **options): + if isinstance(H0, Heaviside) and len(H0.args) == 1: + H0 = S.Half + return super(cls, cls).__new__(cls, arg, H0, **options) + + @property + def pargs(self): + """Args without default S.Half""" + args = self.args + if args[1] is S.Half: + args = args[:1] + return args + + @classmethod + def eval(cls, arg, H0=S.Half): + """ + Returns a simplified form or a value of Heaviside depending on the + argument passed by the Heaviside object. + + Explanation + =========== + + The ``eval()`` method is automatically called when the ``Heaviside`` + class is about to be instantiated and it returns either some simplified + instance or the unevaluated instance depending on the argument passed. + In other words, ``eval()`` method is not needed to be called explicitly, + it is being called and evaluated once the object is called. + + Examples + ======== + + >>> from sympy import Heaviside, S + >>> from sympy.abc import x + + >>> Heaviside(x) + Heaviside(x) + + >>> Heaviside(19) + 1 + + >>> Heaviside(0) + 1/2 + + >>> Heaviside(0, 1) + 1 + + >>> Heaviside(-5) + 0 + + >>> Heaviside(S.NaN) + nan + + >>> Heaviside(x - 100).subs(x, 5) + 0 + + >>> Heaviside(x - 100).subs(x, 105) + 1 + + Parameters + ========== + + arg : argument passed by Heaviside object + + H0 : value of Heaviside(0) + + """ + if arg.is_extended_negative: + return S.Zero + elif arg.is_extended_positive: + return S.One + elif arg.is_zero: + return H0 + elif arg is S.NaN: + return S.NaN + elif fuzzy_not(im(arg).is_zero): + raise ValueError("Function defined only for Real Values. Complex part: %s found in %s ." % (repr(im(arg)), repr(arg)) ) + + def _eval_rewrite_as_Piecewise(self, arg, H0=None, **kwargs): + """ + Represents Heaviside in a Piecewise form. + + Examples + ======== + + >>> from sympy import Heaviside, Piecewise, Symbol, nan + >>> x = Symbol('x') + + >>> Heaviside(x).rewrite(Piecewise) + Piecewise((0, x < 0), (1/2, Eq(x, 0)), (1, True)) + + >>> Heaviside(x,nan).rewrite(Piecewise) + Piecewise((0, x < 0), (nan, Eq(x, 0)), (1, True)) + + >>> Heaviside(x - 5).rewrite(Piecewise) + Piecewise((0, x < 5), (1/2, Eq(x, 5)), (1, True)) + + >>> Heaviside(x**2 - 1).rewrite(Piecewise) + Piecewise((0, x**2 < 1), (1/2, Eq(x**2, 1)), (1, True)) + + """ + if H0 == 0: + return Piecewise((0, arg <= 0), (1, True)) + if H0 == 1: + return Piecewise((0, arg < 0), (1, True)) + return Piecewise((0, arg < 0), (H0, Eq(arg, 0)), (1, True)) + + def _eval_rewrite_as_sign(self, arg, H0=S.Half, **kwargs): + """ + Represents the Heaviside function in the form of sign function. + + Explanation + =========== + + The value of Heaviside(0) must be 1/2 for rewriting as sign to be + strictly equivalent. For easier usage, we also allow this rewriting + when Heaviside(0) is undefined. + + Examples + ======== + + >>> from sympy import Heaviside, Symbol, sign, nan + >>> x = Symbol('x', real=True) + >>> y = Symbol('y') + + >>> Heaviside(x).rewrite(sign) + sign(x)/2 + 1/2 + + >>> Heaviside(x, 0).rewrite(sign) + Piecewise((sign(x)/2 + 1/2, Ne(x, 0)), (0, True)) + + >>> Heaviside(x, nan).rewrite(sign) + Piecewise((sign(x)/2 + 1/2, Ne(x, 0)), (nan, True)) + + >>> Heaviside(x - 2).rewrite(sign) + sign(x - 2)/2 + 1/2 + + >>> Heaviside(x**2 - 2*x + 1).rewrite(sign) + sign(x**2 - 2*x + 1)/2 + 1/2 + + >>> Heaviside(y).rewrite(sign) + Heaviside(y) + + >>> Heaviside(y**2 - 2*y + 1).rewrite(sign) + Heaviside(y**2 - 2*y + 1) + + See Also + ======== + + sign + + """ + if arg.is_extended_real: + pw1 = Piecewise( + ((sign(arg) + 1)/2, Ne(arg, 0)), + (Heaviside(0, H0=H0), True)) + pw2 = Piecewise( + ((sign(arg) + 1)/2, Eq(Heaviside(0, H0=H0), S.Half)), + (pw1, True)) + return pw2 + + def _eval_rewrite_as_SingularityFunction(self, args, H0=S.Half, **kwargs): + """ + Returns the Heaviside expression written in the form of Singularity + Functions. + + """ + from sympy.solvers import solve + from sympy.functions.special.singularity_functions import SingularityFunction + if self == Heaviside(0): + return SingularityFunction(0, 0, 0) + free = self.free_symbols + if len(free) == 1: + x = (free.pop()) + return SingularityFunction(x, solve(args, x)[0], 0) + # TODO + # ((x - 5)**3*Heaviside(x - 5)).rewrite(SingularityFunction) should output + # SingularityFunction(x, 5, 0) instead of (x - 5)**3*SingularityFunction(x, 5, 0) + else: + # I don't know how to handle the case for Heaviside expressions + # having arguments with more than one variable. + raise TypeError(filldedent(''' + rewrite(SingularityFunction) does not + support arguments with more that one variable.''')) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/elliptic_integrals.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/elliptic_integrals.py new file mode 100644 index 0000000000000000000000000000000000000000..a94e343c0106891db44668ae05c33e84ecd05d0b --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/elliptic_integrals.py @@ -0,0 +1,445 @@ +""" Elliptic Integrals. """ + +from sympy.core import S, pi, I, Rational +from sympy.core.function import DefinedFunction, ArgumentIndexError +from sympy.core.symbol import Dummy,uniquely_named_symbol +from sympy.functions.elementary.complexes import sign +from sympy.functions.elementary.hyperbolic import atanh +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import sin, tan +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import hyper, meijerg + +class elliptic_k(DefinedFunction): + r""" + The complete elliptic integral of the first kind, defined by + + .. math:: K(m) = F\left(\tfrac{\pi}{2}\middle| m\right) + + where $F\left(z\middle| m\right)$ is the Legendre incomplete + elliptic integral of the first kind. + + Explanation + =========== + + The function $K(m)$ is a single-valued function on the complex + plane with branch cut along the interval $(1, \infty)$. + + Note that our notation defines the incomplete elliptic integral + in terms of the parameter $m$ instead of the elliptic modulus + (eccentricity) $k$. + In this case, the parameter $m$ is defined as $m=k^2$. + + Examples + ======== + + >>> from sympy import elliptic_k, I + >>> from sympy.abc import m + >>> elliptic_k(0) + pi/2 + >>> elliptic_k(1.0 + I) + 1.50923695405127 + 0.625146415202697*I + >>> elliptic_k(m).series(n=3) + pi/2 + pi*m/8 + 9*pi*m**2/128 + O(m**3) + + See Also + ======== + + elliptic_f + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Elliptic_integrals + .. [2] https://functions.wolfram.com/EllipticIntegrals/EllipticK + + """ + + @classmethod + def eval(cls, m): + if m.is_zero: + return pi*S.Half + elif m is S.Half: + return 8*pi**Rational(3, 2)/gamma(Rational(-1, 4))**2 + elif m is S.One: + return S.ComplexInfinity + elif m is S.NegativeOne: + return gamma(Rational(1, 4))**2/(4*sqrt(2*pi)) + elif m in (S.Infinity, S.NegativeInfinity, I*S.Infinity, + I*S.NegativeInfinity, S.ComplexInfinity): + return S.Zero + + def fdiff(self, argindex=1): + m = self.args[0] + return (elliptic_e(m) - (1 - m)*elliptic_k(m))/(2*m*(1 - m)) + + def _eval_conjugate(self): + m = self.args[0] + if (m.is_real and (m - 1).is_positive) is False: + return self.func(m.conjugate()) + + def _eval_nseries(self, x, n, logx, cdir=0): + from sympy.simplify import hyperexpand + return hyperexpand(self.rewrite(hyper)._eval_nseries(x, n=n, logx=logx)) + + def _eval_rewrite_as_hyper(self, m, **kwargs): + return pi*S.Half*hyper((S.Half, S.Half), (S.One,), m) + + def _eval_rewrite_as_meijerg(self, m, **kwargs): + return meijerg(((S.Half, S.Half), []), ((S.Zero,), (S.Zero,)), -m)/2 + + def _eval_is_zero(self): + m = self.args[0] + if m.is_infinite: + return True + + def _eval_rewrite_as_Integral(self, *args, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', args).name) + m = self.args[0] + return Integral(1/sqrt(1 - m*sin(t)**2), (t, 0, pi/2)) + + +class elliptic_f(DefinedFunction): + r""" + The Legendre incomplete elliptic integral of the first + kind, defined by + + .. math:: F\left(z\middle| m\right) = + \int_0^z \frac{dt}{\sqrt{1 - m \sin^2 t}} + + Explanation + =========== + + This function reduces to a complete elliptic integral of + the first kind, $K(m)$, when $z = \pi/2$. + + Note that our notation defines the incomplete elliptic integral + in terms of the parameter $m$ instead of the elliptic modulus + (eccentricity) $k$. + In this case, the parameter $m$ is defined as $m=k^2$. + + Examples + ======== + + >>> from sympy import elliptic_f, I + >>> from sympy.abc import z, m + >>> elliptic_f(z, m).series(z) + z + z**5*(3*m**2/40 - m/30) + m*z**3/6 + O(z**6) + >>> elliptic_f(3.0 + I/2, 1.0 + I) + 2.909449841483 + 1.74720545502474*I + + See Also + ======== + + elliptic_k + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Elliptic_integrals + .. [2] https://functions.wolfram.com/EllipticIntegrals/EllipticF + + """ + + @classmethod + def eval(cls, z, m): + if z.is_zero: + return S.Zero + if m.is_zero: + return z + k = 2*z/pi + if k.is_integer: + return k*elliptic_k(m) + elif m in (S.Infinity, S.NegativeInfinity): + return S.Zero + elif z.could_extract_minus_sign(): + return -elliptic_f(-z, m) + + def fdiff(self, argindex=1): + z, m = self.args + fm = sqrt(1 - m*sin(z)**2) + if argindex == 1: + return 1/fm + elif argindex == 2: + return (elliptic_e(z, m)/(2*m*(1 - m)) - elliptic_f(z, m)/(2*m) - + sin(2*z)/(4*(1 - m)*fm)) + raise ArgumentIndexError(self, argindex) + + def _eval_conjugate(self): + z, m = self.args + if (m.is_real and (m - 1).is_positive) is False: + return self.func(z.conjugate(), m.conjugate()) + + def _eval_rewrite_as_Integral(self, *args, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', args).name) + z, m = self.args[0], self.args[1] + return Integral(1/(sqrt(1 - m*sin(t)**2)), (t, 0, z)) + + def _eval_is_zero(self): + z, m = self.args + if z.is_zero: + return True + if m.is_extended_real and m.is_infinite: + return True + + +class elliptic_e(DefinedFunction): + r""" + Called with two arguments $z$ and $m$, evaluates the + incomplete elliptic integral of the second kind, defined by + + .. math:: E\left(z\middle| m\right) = \int_0^z \sqrt{1 - m \sin^2 t} dt + + Called with a single argument $m$, evaluates the Legendre complete + elliptic integral of the second kind + + .. math:: E(m) = E\left(\tfrac{\pi}{2}\middle| m\right) + + Explanation + =========== + + The function $E(m)$ is a single-valued function on the complex + plane with branch cut along the interval $(1, \infty)$. + + Note that our notation defines the incomplete elliptic integral + in terms of the parameter $m$ instead of the elliptic modulus + (eccentricity) $k$. + In this case, the parameter $m$ is defined as $m=k^2$. + + Examples + ======== + + >>> from sympy import elliptic_e, I + >>> from sympy.abc import z, m + >>> elliptic_e(z, m).series(z) + z + z**5*(-m**2/40 + m/30) - m*z**3/6 + O(z**6) + >>> elliptic_e(m).series(n=4) + pi/2 - pi*m/8 - 3*pi*m**2/128 - 5*pi*m**3/512 + O(m**4) + >>> elliptic_e(1 + I, 2 - I/2).n() + 1.55203744279187 + 0.290764986058437*I + >>> elliptic_e(0) + pi/2 + >>> elliptic_e(2.0 - I) + 0.991052601328069 + 0.81879421395609*I + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Elliptic_integrals + .. [2] https://functions.wolfram.com/EllipticIntegrals/EllipticE2 + .. [3] https://functions.wolfram.com/EllipticIntegrals/EllipticE + + """ + + @classmethod + def eval(cls, m, z=None): + if z is not None: + z, m = m, z + k = 2*z/pi + if m.is_zero: + return z + if z.is_zero: + return S.Zero + elif k.is_integer: + return k*elliptic_e(m) + elif m in (S.Infinity, S.NegativeInfinity): + return S.ComplexInfinity + elif z.could_extract_minus_sign(): + return -elliptic_e(-z, m) + else: + if m.is_zero: + return pi/2 + elif m is S.One: + return S.One + elif m is S.Infinity: + return I*S.Infinity + elif m is S.NegativeInfinity: + return S.Infinity + elif m is S.ComplexInfinity: + return S.ComplexInfinity + + def fdiff(self, argindex=1): + if len(self.args) == 2: + z, m = self.args + if argindex == 1: + return sqrt(1 - m*sin(z)**2) + elif argindex == 2: + return (elliptic_e(z, m) - elliptic_f(z, m))/(2*m) + else: + m = self.args[0] + if argindex == 1: + return (elliptic_e(m) - elliptic_k(m))/(2*m) + raise ArgumentIndexError(self, argindex) + + def _eval_conjugate(self): + if len(self.args) == 2: + z, m = self.args + if (m.is_real and (m - 1).is_positive) is False: + return self.func(z.conjugate(), m.conjugate()) + else: + m = self.args[0] + if (m.is_real and (m - 1).is_positive) is False: + return self.func(m.conjugate()) + + def _eval_nseries(self, x, n, logx, cdir=0): + from sympy.simplify import hyperexpand + if len(self.args) == 1: + return hyperexpand(self.rewrite(hyper)._eval_nseries(x, n=n, logx=logx)) + return super()._eval_nseries(x, n=n, logx=logx) + + def _eval_rewrite_as_hyper(self, *args, **kwargs): + if len(args) == 1: + m = args[0] + return (pi/2)*hyper((Rational(-1, 2), S.Half), (S.One,), m) + + def _eval_rewrite_as_meijerg(self, *args, **kwargs): + if len(args) == 1: + m = args[0] + return -meijerg(((S.Half, Rational(3, 2)), []), \ + ((S.Zero,), (S.Zero,)), -m)/4 + + def _eval_rewrite_as_Integral(self, *args, **kwargs): + from sympy.integrals.integrals import Integral + z, m = (pi/2, self.args[0]) if len(self.args) == 1 else self.args + t = Dummy(uniquely_named_symbol('t', args).name) + return Integral(sqrt(1 - m*sin(t)**2), (t, 0, z)) + + +class elliptic_pi(DefinedFunction): + r""" + Called with three arguments $n$, $z$ and $m$, evaluates the + Legendre incomplete elliptic integral of the third kind, defined by + + .. math:: \Pi\left(n; z\middle| m\right) = \int_0^z \frac{dt} + {\left(1 - n \sin^2 t\right) \sqrt{1 - m \sin^2 t}} + + Called with two arguments $n$ and $m$, evaluates the complete + elliptic integral of the third kind: + + .. math:: \Pi\left(n\middle| m\right) = + \Pi\left(n; \tfrac{\pi}{2}\middle| m\right) + + Explanation + =========== + + Note that our notation defines the incomplete elliptic integral + in terms of the parameter $m$ instead of the elliptic modulus + (eccentricity) $k$. + In this case, the parameter $m$ is defined as $m=k^2$. + + Examples + ======== + + >>> from sympy import elliptic_pi, I + >>> from sympy.abc import z, n, m + >>> elliptic_pi(n, z, m).series(z, n=4) + z + z**3*(m/6 + n/3) + O(z**4) + >>> elliptic_pi(0.5 + I, 1.0 - I, 1.2) + 2.50232379629182 - 0.760939574180767*I + >>> elliptic_pi(0, 0) + pi/2 + >>> elliptic_pi(1.0 - I/3, 2.0 + I) + 3.29136443417283 + 0.32555634906645*I + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Elliptic_integrals + .. [2] https://functions.wolfram.com/EllipticIntegrals/EllipticPi3 + .. [3] https://functions.wolfram.com/EllipticIntegrals/EllipticPi + + """ + + @classmethod + def eval(cls, n, m, z=None): + if z is not None: + z, m = m, z + if n.is_zero: + return elliptic_f(z, m) + elif n is S.One: + return (elliptic_f(z, m) + + (sqrt(1 - m*sin(z)**2)*tan(z) - + elliptic_e(z, m))/(1 - m)) + k = 2*z/pi + if k.is_integer: + return k*elliptic_pi(n, m) + elif m.is_zero: + return atanh(sqrt(n - 1)*tan(z))/sqrt(n - 1) + elif n == m: + return (elliptic_f(z, n) - elliptic_pi(1, z, n) + + tan(z)/sqrt(1 - n*sin(z)**2)) + elif n in (S.Infinity, S.NegativeInfinity): + return S.Zero + elif m in (S.Infinity, S.NegativeInfinity): + return S.Zero + elif z.could_extract_minus_sign(): + return -elliptic_pi(n, -z, m) + if n.is_zero: + return elliptic_f(z, m) + if m.is_extended_real and m.is_infinite or \ + n.is_extended_real and n.is_infinite: + return S.Zero + else: + if n.is_zero: + return elliptic_k(m) + elif n is S.One: + return S.ComplexInfinity + elif m.is_zero: + return pi/(2*sqrt(1 - n)) + elif m == S.One: + return S.NegativeInfinity/sign(n - 1) + elif n == m: + return elliptic_e(n)/(1 - n) + elif n in (S.Infinity, S.NegativeInfinity): + return S.Zero + elif m in (S.Infinity, S.NegativeInfinity): + return S.Zero + if n.is_zero: + return elliptic_k(m) + if m.is_extended_real and m.is_infinite or \ + n.is_extended_real and n.is_infinite: + return S.Zero + + def _eval_conjugate(self): + if len(self.args) == 3: + n, z, m = self.args + if (n.is_real and (n - 1).is_positive) is False and \ + (m.is_real and (m - 1).is_positive) is False: + return self.func(n.conjugate(), z.conjugate(), m.conjugate()) + else: + n, m = self.args + return self.func(n.conjugate(), m.conjugate()) + + def fdiff(self, argindex=1): + if len(self.args) == 3: + n, z, m = self.args + fm, fn = sqrt(1 - m*sin(z)**2), 1 - n*sin(z)**2 + if argindex == 1: + return (elliptic_e(z, m) + (m - n)*elliptic_f(z, m)/n + + (n**2 - m)*elliptic_pi(n, z, m)/n - + n*fm*sin(2*z)/(2*fn))/(2*(m - n)*(n - 1)) + elif argindex == 2: + return 1/(fm*fn) + elif argindex == 3: + return (elliptic_e(z, m)/(m - 1) + + elliptic_pi(n, z, m) - + m*sin(2*z)/(2*(m - 1)*fm))/(2*(n - m)) + else: + n, m = self.args + if argindex == 1: + return (elliptic_e(m) + (m - n)*elliptic_k(m)/n + + (n**2 - m)*elliptic_pi(n, m)/n)/(2*(m - n)*(n - 1)) + elif argindex == 2: + return (elliptic_e(m)/(m - 1) + elliptic_pi(n, m))/(2*(n - m)) + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Integral(self, *args, **kwargs): + from sympy.integrals.integrals import Integral + if len(self.args) == 2: + n, m, z = self.args[0], self.args[1], pi/2 + else: + n, z, m = self.args + t = Dummy(uniquely_named_symbol('t', args).name) + return Integral(1/((1 - n*sin(t)**2)*sqrt(1 - m*sin(t)**2)), (t, 0, z)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/error_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/error_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..a778127d8b80583a892285fadbb8230f72de39f9 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/error_functions.py @@ -0,0 +1,2801 @@ +""" This module contains various functions that are special cases + of incomplete gamma functions. It should probably be renamed. """ + +from sympy.core import EulerGamma # Must be imported from core, not core.numbers +from sympy.core.add import Add +from sympy.core.cache import cacheit +from sympy.core.function import DefinedFunction, ArgumentIndexError, expand_mul +from sympy.core.logic import fuzzy_or +from sympy.core.numbers import I, pi, Rational, Integer +from sympy.core.relational import is_eq +from sympy.core.power import Pow +from sympy.core.singleton import S +from sympy.core.symbol import Dummy, uniquely_named_symbol +from sympy.core.sympify import sympify +from sympy.functions.combinatorial.factorials import factorial, factorial2, RisingFactorial +from sympy.functions.elementary.complexes import polar_lift, re, unpolarify +from sympy.functions.elementary.integers import ceiling, floor +from sympy.functions.elementary.miscellaneous import sqrt, root +from sympy.functions.elementary.exponential import exp, log, exp_polar +from sympy.functions.elementary.hyperbolic import cosh, sinh +from sympy.functions.elementary.trigonometric import cos, sin, sinc +from sympy.functions.special.hyper import hyper, meijerg + +# TODO series expansions +# TODO see the "Note:" in Ei + +# Helper function +def real_to_real_as_real_imag(self, deep=True, **hints): + if self.args[0].is_extended_real: + if deep: + hints['complex'] = False + return (self.expand(deep, **hints), S.Zero) + else: + return (self, S.Zero) + if deep: + x, y = self.args[0].expand(deep, **hints).as_real_imag() + else: + x, y = self.args[0].as_real_imag() + re = (self.func(x + I*y) + self.func(x - I*y))/2 + im = (self.func(x + I*y) - self.func(x - I*y))/(2*I) + return (re, im) + + +############################################################################### +################################ ERROR FUNCTION ############################### +############################################################################### + + +class erf(DefinedFunction): + r""" + The Gauss error function. + + Explanation + =========== + + This function is defined as: + + .. math :: + \mathrm{erf}(x) = \frac{2}{\sqrt{\pi}} \int_0^x e^{-t^2} \mathrm{d}t. + + Examples + ======== + + >>> from sympy import I, oo, erf + >>> from sympy.abc import z + + Several special values are known: + + >>> erf(0) + 0 + >>> erf(oo) + 1 + >>> erf(-oo) + -1 + >>> erf(I*oo) + oo*I + >>> erf(-I*oo) + -oo*I + + In general one can pull out factors of -1 and $I$ from the argument: + + >>> erf(-z) + -erf(z) + + The error function obeys the mirror symmetry: + + >>> from sympy import conjugate + >>> conjugate(erf(z)) + erf(conjugate(z)) + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(erf(z), z) + 2*exp(-z**2)/sqrt(pi) + + We can numerically evaluate the error function to arbitrary precision + on the whole complex plane: + + >>> erf(4).evalf(30) + 0.999999984582742099719981147840 + + >>> erf(-4*I).evalf(30) + -1296959.73071763923152794095062*I + + See Also + ======== + + erfc: Complementary error function. + erfi: Imaginary error function. + erf2: Two-argument error function. + erfinv: Inverse error function. + erfcinv: Inverse Complementary error function. + erf2inv: Inverse two-argument error function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Error_function + .. [2] https://dlmf.nist.gov/7 + .. [3] https://mathworld.wolfram.com/Erf.html + .. [4] https://functions.wolfram.com/GammaBetaErf/Erf + + """ + + unbranched = True + + def fdiff(self, argindex=1): + if argindex == 1: + return 2*exp(-self.args[0]**2)/sqrt(pi) + else: + raise ArgumentIndexError(self, argindex) + + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + + """ + return erfinv + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.One + elif arg is S.NegativeInfinity: + return S.NegativeOne + elif arg.is_zero: + return S.Zero + + if isinstance(arg, erfinv): + return arg.args[0] + + if isinstance(arg, erfcinv): + return S.One - arg.args[0] + + if arg.is_zero: + return S.Zero + + # Only happens with unevaluated erf2inv + if isinstance(arg, erf2inv) and arg.args[0].is_zero: + return arg.args[1] + + # Try to pull out factors of I + t = arg.extract_multiplicatively(I) + if t in (S.Infinity, S.NegativeInfinity): + return arg + + # Try to pull out factors of -1 + if arg.could_extract_minus_sign(): + return -cls(-arg) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + k = floor((n - 1)/S(2)) + if len(previous_terms) > 2: + return -previous_terms[-2] * x**2 * (n - 2)/(n*k) + else: + return 2*S.NegativeOne**k * x**n/(n*factorial(k)*sqrt(pi)) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def _eval_is_real(self): + if self.args[0].is_extended_real is True: + return True + # There are cases where erf(z) becomes a real number + # even if z is a complex number + + def _eval_is_imaginary(self): + if self.args[0].is_imaginary is True: + return True + + def _eval_is_finite(self): + z = self.args[0] + return fuzzy_or([z.is_finite, z.is_extended_real]) + + def _eval_is_zero(self): + if self.args[0].is_extended_real is True: + return self.args[0].is_zero + + def _eval_is_positive(self): + if self.args[0].is_extended_real is True: + return self.args[0].is_extended_positive + + def _eval_is_negative(self): + if self.args[0].is_extended_real is True: + return self.args[0].is_extended_negative + + def _eval_rewrite_as_uppergamma(self, z, **kwargs): + from sympy.functions.special.gamma_functions import uppergamma + return sqrt(z**2)/z*(S.One - uppergamma(S.Half, z**2)/sqrt(pi)) + + def _eval_rewrite_as_fresnels(self, z, **kwargs): + arg = (S.One - I)*z/sqrt(pi) + return (S.One + I)*(fresnelc(arg) - I*fresnels(arg)) + + def _eval_rewrite_as_fresnelc(self, z, **kwargs): + arg = (S.One - I)*z/sqrt(pi) + return (S.One + I)*(fresnelc(arg) - I*fresnels(arg)) + + def _eval_rewrite_as_meijerg(self, z, **kwargs): + return z/sqrt(pi)*meijerg([S.Half], [], [0], [Rational(-1, 2)], z**2) + + def _eval_rewrite_as_hyper(self, z, **kwargs): + return 2*z/sqrt(pi)*hyper([S.Half], [3*S.Half], -z**2) + + def _eval_rewrite_as_expint(self, z, **kwargs): + return sqrt(z**2)/z - z*expint(S.Half, z**2)/sqrt(pi) + + def _eval_rewrite_as_tractable(self, z, limitvar=None, **kwargs): + from sympy.series.limits import limit + if limitvar: + lim = limit(z, limitvar, S.Infinity) + if lim is S.NegativeInfinity: + return S.NegativeOne + _erfs(-z)*exp(-z**2) + return S.One - _erfs(z)*exp(-z**2) + + def _eval_rewrite_as_erfc(self, z, **kwargs): + return S.One - erfc(z) + + def _eval_rewrite_as_erfi(self, z, **kwargs): + return -I*erfi(I*z) + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if arg0 is S.ComplexInfinity: + arg0 = arg.limit(x, 0, dir='-' if cdir == -1 else '+') + if x in arg.free_symbols and arg0.is_zero: + return 2*arg/sqrt(pi) + else: + return self.func(arg0) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + point = args0[0] + + if point in [S.Infinity, S.NegativeInfinity]: + z = self.args[0] + + try: + _, ex = z.leadterm(x) + except (ValueError, NotImplementedError): + return self + + ex = -ex # as x->1/x for aseries + if ex.is_positive: + newn = ceiling(n/ex) + s = [S.NegativeOne**k * factorial2(2*k - 1) / (z**(2*k + 1) * 2**k) + for k in range(newn)] + [Order(1/z**newn, x)] + return S.One - (exp(-z**2)/sqrt(pi)) * Add(*s) + + return super(erf, self)._eval_aseries(n, args0, x, logx) + + as_real_imag = real_to_real_as_real_imag + + +class erfc(DefinedFunction): + r""" + Complementary Error Function. + + Explanation + =========== + + The function is defined as: + + .. math :: + \mathrm{erfc}(x) = \frac{2}{\sqrt{\pi}} \int_x^\infty e^{-t^2} \mathrm{d}t + + Examples + ======== + + >>> from sympy import I, oo, erfc + >>> from sympy.abc import z + + Several special values are known: + + >>> erfc(0) + 1 + >>> erfc(oo) + 0 + >>> erfc(-oo) + 2 + >>> erfc(I*oo) + -oo*I + >>> erfc(-I*oo) + oo*I + + The error function obeys the mirror symmetry: + + >>> from sympy import conjugate + >>> conjugate(erfc(z)) + erfc(conjugate(z)) + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(erfc(z), z) + -2*exp(-z**2)/sqrt(pi) + + It also follows + + >>> erfc(-z) + 2 - erfc(z) + + We can numerically evaluate the complementary error function to arbitrary + precision on the whole complex plane: + + >>> erfc(4).evalf(30) + 0.0000000154172579002800188521596734869 + + >>> erfc(4*I).evalf(30) + 1.0 - 1296959.73071763923152794095062*I + + See Also + ======== + + erf: Gaussian error function. + erfi: Imaginary error function. + erf2: Two-argument error function. + erfinv: Inverse error function. + erfcinv: Inverse Complementary error function. + erf2inv: Inverse two-argument error function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Error_function + .. [2] https://dlmf.nist.gov/7 + .. [3] https://mathworld.wolfram.com/Erfc.html + .. [4] https://functions.wolfram.com/GammaBetaErf/Erfc + + """ + + unbranched = True + + def fdiff(self, argindex=1): + if argindex == 1: + return -2*exp(-self.args[0]**2)/sqrt(pi) + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + + """ + return erfcinv + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is S.Infinity: + return S.Zero + elif arg.is_zero: + return S.One + + if isinstance(arg, erfinv): + return S.One - arg.args[0] + + if isinstance(arg, erfcinv): + return arg.args[0] + + if arg.is_zero: + return S.One + + # Try to pull out factors of I + t = arg.extract_multiplicatively(I) + if t in (S.Infinity, S.NegativeInfinity): + return -arg + + # Try to pull out factors of -1 + if arg.could_extract_minus_sign(): + return 2 - cls(-arg) + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n == 0: + return S.One + elif n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + k = floor((n - 1)/S(2)) + if len(previous_terms) > 2: + return -previous_terms[-2] * x**2 * (n - 2)/(n*k) + else: + return -2*S.NegativeOne**k * x**n/(n*factorial(k)*sqrt(pi)) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def _eval_is_real(self): + if self.args[0].is_extended_real is True: + return True + if self.args[0].is_imaginary is True: + return False + + def _eval_rewrite_as_tractable(self, z, limitvar=None, **kwargs): + return self.rewrite(erf).rewrite("tractable", deep=True, limitvar=limitvar) + + def _eval_rewrite_as_erf(self, z, **kwargs): + return S.One - erf(z) + + def _eval_rewrite_as_erfi(self, z, **kwargs): + return S.One + I*erfi(I*z) + + def _eval_rewrite_as_fresnels(self, z, **kwargs): + arg = (S.One - I)*z/sqrt(pi) + return S.One - (S.One + I)*(fresnelc(arg) - I*fresnels(arg)) + + def _eval_rewrite_as_fresnelc(self, z, **kwargs): + arg = (S.One-I)*z/sqrt(pi) + return S.One - (S.One + I)*(fresnelc(arg) - I*fresnels(arg)) + + def _eval_rewrite_as_meijerg(self, z, **kwargs): + return S.One - z/sqrt(pi)*meijerg([S.Half], [], [0], [Rational(-1, 2)], z**2) + + def _eval_rewrite_as_hyper(self, z, **kwargs): + return S.One - 2*z/sqrt(pi)*hyper([S.Half], [3*S.Half], -z**2) + + def _eval_rewrite_as_uppergamma(self, z, **kwargs): + from sympy.functions.special.gamma_functions import uppergamma + return S.One - sqrt(z**2)/z*(S.One - uppergamma(S.Half, z**2)/sqrt(pi)) + + def _eval_rewrite_as_expint(self, z, **kwargs): + return S.One - sqrt(z**2)/z + z*expint(S.Half, z**2)/sqrt(pi) + + def _eval_expand_func(self, **hints): + return self.rewrite(erf) + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if arg0 is S.ComplexInfinity: + arg0 = arg.limit(x, 0, dir='-' if cdir == -1 else '+') + if arg0.is_zero: + return S.One + else: + return self.func(arg0) + + as_real_imag = real_to_real_as_real_imag + + def _eval_aseries(self, n, args0, x, logx): + return S.One - erf(*self.args)._eval_aseries(n, args0, x, logx) + + +class erfi(DefinedFunction): + r""" + Imaginary error function. + + Explanation + =========== + + The function erfi is defined as: + + .. math :: + \mathrm{erfi}(x) = \frac{2}{\sqrt{\pi}} \int_0^x e^{t^2} \mathrm{d}t + + Examples + ======== + + >>> from sympy import I, oo, erfi + >>> from sympy.abc import z + + Several special values are known: + + >>> erfi(0) + 0 + >>> erfi(oo) + oo + >>> erfi(-oo) + -oo + >>> erfi(I*oo) + I + >>> erfi(-I*oo) + -I + + In general one can pull out factors of -1 and $I$ from the argument: + + >>> erfi(-z) + -erfi(z) + + >>> from sympy import conjugate + >>> conjugate(erfi(z)) + erfi(conjugate(z)) + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(erfi(z), z) + 2*exp(z**2)/sqrt(pi) + + We can numerically evaluate the imaginary error function to arbitrary + precision on the whole complex plane: + + >>> erfi(2).evalf(30) + 18.5648024145755525987042919132 + + >>> erfi(-2*I).evalf(30) + -0.995322265018952734162069256367*I + + See Also + ======== + + erf: Gaussian error function. + erfc: Complementary error function. + erf2: Two-argument error function. + erfinv: Inverse error function. + erfcinv: Inverse Complementary error function. + erf2inv: Inverse two-argument error function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Error_function + .. [2] https://mathworld.wolfram.com/Erfi.html + .. [3] https://functions.wolfram.com/GammaBetaErf/Erfi + + """ + + unbranched = True + + def fdiff(self, argindex=1): + if argindex == 1: + return 2*exp(self.args[0]**2)/sqrt(pi) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, z): + if z.is_Number: + if z is S.NaN: + return S.NaN + elif z.is_zero: + return S.Zero + elif z is S.Infinity: + return S.Infinity + + if z.is_zero: + return S.Zero + + # Try to pull out factors of -1 + if z.could_extract_minus_sign(): + return -cls(-z) + + # Try to pull out factors of I + nz = z.extract_multiplicatively(I) + if nz is not None: + if nz is S.Infinity: + return I + if isinstance(nz, erfinv): + return I*nz.args[0] + if isinstance(nz, erfcinv): + return I*(S.One - nz.args[0]) + # Only happens with unevaluated erf2inv + if isinstance(nz, erf2inv) and nz.args[0].is_zero: + return I*nz.args[1] + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0 or n % 2 == 0: + return S.Zero + else: + x = sympify(x) + k = floor((n - 1)/S(2)) + if len(previous_terms) > 2: + return previous_terms[-2] * x**2 * (n - 2)/(n*k) + else: + return 2 * x**n/(n*factorial(k)*sqrt(pi)) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def _eval_is_extended_real(self): + return self.args[0].is_extended_real + + def _eval_is_zero(self): + return self.args[0].is_zero + + def _eval_rewrite_as_tractable(self, z, limitvar=None, **kwargs): + return self.rewrite(erf).rewrite("tractable", deep=True, limitvar=limitvar) + + def _eval_rewrite_as_erf(self, z, **kwargs): + return -I*erf(I*z) + + def _eval_rewrite_as_erfc(self, z, **kwargs): + return I*erfc(I*z) - I + + def _eval_rewrite_as_fresnels(self, z, **kwargs): + arg = (S.One + I)*z/sqrt(pi) + return (S.One - I)*(fresnelc(arg) - I*fresnels(arg)) + + def _eval_rewrite_as_fresnelc(self, z, **kwargs): + arg = (S.One + I)*z/sqrt(pi) + return (S.One - I)*(fresnelc(arg) - I*fresnels(arg)) + + def _eval_rewrite_as_meijerg(self, z, **kwargs): + return z/sqrt(pi)*meijerg([S.Half], [], [0], [Rational(-1, 2)], -z**2) + + def _eval_rewrite_as_hyper(self, z, **kwargs): + return 2*z/sqrt(pi)*hyper([S.Half], [3*S.Half], z**2) + + def _eval_rewrite_as_uppergamma(self, z, **kwargs): + from sympy.functions.special.gamma_functions import uppergamma + return sqrt(-z**2)/z*(uppergamma(S.Half, -z**2)/sqrt(pi) - S.One) + + def _eval_rewrite_as_expint(self, z, **kwargs): + return sqrt(-z**2)/z - z*expint(S.Half, -z**2)/sqrt(pi) + + def _eval_expand_func(self, **hints): + return self.rewrite(erf) + + as_real_imag = real_to_real_as_real_imag + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if x in arg.free_symbols and arg0.is_zero: + return 2*arg/sqrt(pi) + elif arg0.is_finite: + return self.func(arg0) + return self.func(arg) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + point = args0[0] + + if point is S.Infinity: + z = self.args[0] + s = [factorial2(2*k - 1) / (2**k * z**(2*k + 1)) + for k in range(n)] + [Order(1/z**n, x)] + return -I + (exp(z**2)/sqrt(pi)) * Add(*s) + + return super(erfi, self)._eval_aseries(n, args0, x, logx) + + +class erf2(DefinedFunction): + r""" + Two-argument error function. + + Explanation + =========== + + This function is defined as: + + .. math :: + \mathrm{erf2}(x, y) = \frac{2}{\sqrt{\pi}} \int_x^y e^{-t^2} \mathrm{d}t + + Examples + ======== + + >>> from sympy import oo, erf2 + >>> from sympy.abc import x, y + + Several special values are known: + + >>> erf2(0, 0) + 0 + >>> erf2(x, x) + 0 + >>> erf2(x, oo) + 1 - erf(x) + >>> erf2(x, -oo) + -erf(x) - 1 + >>> erf2(oo, y) + erf(y) - 1 + >>> erf2(-oo, y) + erf(y) + 1 + + In general one can pull out factors of -1: + + >>> erf2(-x, -y) + -erf2(x, y) + + The error function obeys the mirror symmetry: + + >>> from sympy import conjugate + >>> conjugate(erf2(x, y)) + erf2(conjugate(x), conjugate(y)) + + Differentiation with respect to $x$, $y$ is supported: + + >>> from sympy import diff + >>> diff(erf2(x, y), x) + -2*exp(-x**2)/sqrt(pi) + >>> diff(erf2(x, y), y) + 2*exp(-y**2)/sqrt(pi) + + See Also + ======== + + erf: Gaussian error function. + erfc: Complementary error function. + erfi: Imaginary error function. + erfinv: Inverse error function. + erfcinv: Inverse Complementary error function. + erf2inv: Inverse two-argument error function. + + References + ========== + + .. [1] https://functions.wolfram.com/GammaBetaErf/Erf2/ + + """ + + + def fdiff(self, argindex): + x, y = self.args + if argindex == 1: + return -2*exp(-x**2)/sqrt(pi) + elif argindex == 2: + return 2*exp(-y**2)/sqrt(pi) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, x, y): + chk = (S.Infinity, S.NegativeInfinity, S.Zero) + if x is S.NaN or y is S.NaN: + return S.NaN + elif x == y: + return S.Zero + elif x in chk or y in chk: + return erf(y) - erf(x) + + if isinstance(y, erf2inv) and y.args[0] == x: + return y.args[1] + + if x.is_zero or y.is_zero or x.is_extended_real and x.is_infinite or \ + y.is_extended_real and y.is_infinite: + return erf(y) - erf(x) + + #Try to pull out -1 factor + sign_x = x.could_extract_minus_sign() + sign_y = y.could_extract_minus_sign() + if (sign_x and sign_y): + return -cls(-x, -y) + elif (sign_x or sign_y): + return erf(y)-erf(x) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate(), self.args[1].conjugate()) + + def _eval_is_extended_real(self): + return self.args[0].is_extended_real and self.args[1].is_extended_real + + def _eval_rewrite_as_erf(self, x, y, **kwargs): + return erf(y) - erf(x) + + def _eval_rewrite_as_erfc(self, x, y, **kwargs): + return erfc(x) - erfc(y) + + def _eval_rewrite_as_erfi(self, x, y, **kwargs): + return I*(erfi(I*x)-erfi(I*y)) + + def _eval_rewrite_as_fresnels(self, x, y, **kwargs): + return erf(y).rewrite(fresnels) - erf(x).rewrite(fresnels) + + def _eval_rewrite_as_fresnelc(self, x, y, **kwargs): + return erf(y).rewrite(fresnelc) - erf(x).rewrite(fresnelc) + + def _eval_rewrite_as_meijerg(self, x, y, **kwargs): + return erf(y).rewrite(meijerg) - erf(x).rewrite(meijerg) + + def _eval_rewrite_as_hyper(self, x, y, **kwargs): + return erf(y).rewrite(hyper) - erf(x).rewrite(hyper) + + def _eval_rewrite_as_uppergamma(self, x, y, **kwargs): + from sympy.functions.special.gamma_functions import uppergamma + return (sqrt(y**2)/y*(S.One - uppergamma(S.Half, y**2)/sqrt(pi)) - + sqrt(x**2)/x*(S.One - uppergamma(S.Half, x**2)/sqrt(pi))) + + def _eval_rewrite_as_expint(self, x, y, **kwargs): + return erf(y).rewrite(expint) - erf(x).rewrite(expint) + + def _eval_expand_func(self, **hints): + return self.rewrite(erf) + + def _eval_is_zero(self): + return is_eq(*self.args) + +class erfinv(DefinedFunction): + r""" + Inverse Error Function. The erfinv function is defined as: + + .. math :: + \mathrm{erf}(x) = y \quad \Rightarrow \quad \mathrm{erfinv}(y) = x + + Examples + ======== + + >>> from sympy import erfinv + >>> from sympy.abc import x + + Several special values are known: + + >>> erfinv(0) + 0 + >>> erfinv(1) + oo + + Differentiation with respect to $x$ is supported: + + >>> from sympy import diff + >>> diff(erfinv(x), x) + sqrt(pi)*exp(erfinv(x)**2)/2 + + We can numerically evaluate the inverse error function to arbitrary + precision on [-1, 1]: + + >>> erfinv(0.2).evalf(30) + 0.179143454621291692285822705344 + + See Also + ======== + + erf: Gaussian error function. + erfc: Complementary error function. + erfi: Imaginary error function. + erf2: Two-argument error function. + erfcinv: Inverse Complementary error function. + erf2inv: Inverse two-argument error function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Error_function#Inverse_functions + .. [2] https://functions.wolfram.com/GammaBetaErf/InverseErf/ + + """ + + + def fdiff(self, argindex =1): + if argindex == 1: + return sqrt(pi)*exp(self.func(self.args[0])**2)*S.Half + else : + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + + """ + return erf + + @classmethod + def eval(cls, z): + if z is S.NaN: + return S.NaN + elif z is S.NegativeOne: + return S.NegativeInfinity + elif z.is_zero: + return S.Zero + elif z is S.One: + return S.Infinity + + if isinstance(z, erf) and z.args[0].is_extended_real: + return z.args[0] + + if z.is_zero: + return S.Zero + + # Try to pull out factors of -1 + nz = z.extract_multiplicatively(-1) + if nz is not None and (isinstance(nz, erf) and (nz.args[0]).is_extended_real): + return -nz.args[0] + + def _eval_rewrite_as_erfcinv(self, z, **kwargs): + return erfcinv(1-z) + + def _eval_is_zero(self): + return self.args[0].is_zero + + +class erfcinv (DefinedFunction): + r""" + Inverse Complementary Error Function. The erfcinv function is defined as: + + .. math :: + \mathrm{erfc}(x) = y \quad \Rightarrow \quad \mathrm{erfcinv}(y) = x + + Examples + ======== + + >>> from sympy import erfcinv + >>> from sympy.abc import x + + Several special values are known: + + >>> erfcinv(1) + 0 + >>> erfcinv(0) + oo + + Differentiation with respect to $x$ is supported: + + >>> from sympy import diff + >>> diff(erfcinv(x), x) + -sqrt(pi)*exp(erfcinv(x)**2)/2 + + See Also + ======== + + erf: Gaussian error function. + erfc: Complementary error function. + erfi: Imaginary error function. + erf2: Two-argument error function. + erfinv: Inverse error function. + erf2inv: Inverse two-argument error function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Error_function#Inverse_functions + .. [2] https://functions.wolfram.com/GammaBetaErf/InverseErfc/ + + """ + + + def fdiff(self, argindex =1): + if argindex == 1: + return -sqrt(pi)*exp(self.func(self.args[0])**2)*S.Half + else: + raise ArgumentIndexError(self, argindex) + + def inverse(self, argindex=1): + """ + Returns the inverse of this function. + + """ + return erfc + + @classmethod + def eval(cls, z): + if z is S.NaN: + return S.NaN + elif z.is_zero: + return S.Infinity + elif z is S.One: + return S.Zero + elif z == 2: + return S.NegativeInfinity + + if z.is_zero: + return S.Infinity + + def _eval_rewrite_as_erfinv(self, z, **kwargs): + return erfinv(1-z) + + def _eval_is_zero(self): + return (self.args[0] - 1).is_zero + + def _eval_is_infinite(self): + z = self.args[0] + return fuzzy_or([z.is_zero, is_eq(z, Integer(2))]) + + +class erf2inv(DefinedFunction): + r""" + Two-argument Inverse error function. The erf2inv function is defined as: + + .. math :: + \mathrm{erf2}(x, w) = y \quad \Rightarrow \quad \mathrm{erf2inv}(x, y) = w + + Examples + ======== + + >>> from sympy import erf2inv, oo + >>> from sympy.abc import x, y + + Several special values are known: + + >>> erf2inv(0, 0) + 0 + >>> erf2inv(1, 0) + 1 + >>> erf2inv(0, 1) + oo + >>> erf2inv(0, y) + erfinv(y) + >>> erf2inv(oo, y) + erfcinv(-y) + + Differentiation with respect to $x$ and $y$ is supported: + + >>> from sympy import diff + >>> diff(erf2inv(x, y), x) + exp(-x**2 + erf2inv(x, y)**2) + >>> diff(erf2inv(x, y), y) + sqrt(pi)*exp(erf2inv(x, y)**2)/2 + + See Also + ======== + + erf: Gaussian error function. + erfc: Complementary error function. + erfi: Imaginary error function. + erf2: Two-argument error function. + erfinv: Inverse error function. + erfcinv: Inverse complementary error function. + + References + ========== + + .. [1] https://functions.wolfram.com/GammaBetaErf/InverseErf2/ + + """ + + + def fdiff(self, argindex): + x, y = self.args + if argindex == 1: + return exp(self.func(x,y)**2-x**2) + elif argindex == 2: + return sqrt(pi)*S.Half*exp(self.func(x,y)**2) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, x, y): + if x is S.NaN or y is S.NaN: + return S.NaN + elif x.is_zero and y.is_zero: + return S.Zero + elif x.is_zero and y is S.One: + return S.Infinity + elif x is S.One and y.is_zero: + return S.One + elif x.is_zero: + return erfinv(y) + elif x is S.Infinity: + return erfcinv(-y) + elif y.is_zero: + return x + elif y is S.Infinity: + return erfinv(x) + + if x.is_zero: + if y.is_zero: + return S.Zero + else: + return erfinv(y) + if y.is_zero: + return x + + def _eval_is_zero(self): + x, y = self.args + if x.is_zero and y.is_zero: + return True + +############################################################################### +#################### EXPONENTIAL INTEGRALS #################################### +############################################################################### + +class Ei(DefinedFunction): + r""" + The classical exponential integral. + + Explanation + =========== + + For use in SymPy, this function is defined as + + .. math:: \operatorname{Ei}(x) = \sum_{n=1}^\infty \frac{x^n}{n\, n!} + + \log(x) + \gamma, + + where $\gamma$ is the Euler-Mascheroni constant. + + If $x$ is a polar number, this defines an analytic function on the + Riemann surface of the logarithm. Otherwise this defines an analytic + function in the cut plane $\mathbb{C} \setminus (-\infty, 0]$. + + **Background** + + The name exponential integral comes from the following statement: + + .. math:: \operatorname{Ei}(x) = \int_{-\infty}^x \frac{e^t}{t} \mathrm{d}t + + If the integral is interpreted as a Cauchy principal value, this statement + holds for $x > 0$ and $\operatorname{Ei}(x)$ as defined above. + + Examples + ======== + + >>> from sympy import Ei, polar_lift, exp_polar, I, pi + >>> from sympy.abc import x + + >>> Ei(-1) + Ei(-1) + + This yields a real value: + + >>> Ei(-1).n(chop=True) + -0.219383934395520 + + On the other hand the analytic continuation is not real: + + >>> Ei(polar_lift(-1)).n(chop=True) + -0.21938393439552 + 3.14159265358979*I + + The exponential integral has a logarithmic branch point at the origin: + + >>> Ei(x*exp_polar(2*I*pi)) + Ei(x) + 2*I*pi + + Differentiation is supported: + + >>> Ei(x).diff(x) + exp(x)/x + + The exponential integral is related to many other special functions. + For example: + + >>> from sympy import expint, Shi + >>> Ei(x).rewrite(expint) + -expint(1, x*exp_polar(I*pi)) - I*pi + >>> Ei(x).rewrite(Shi) + Chi(x) + Shi(x) + + See Also + ======== + + expint: Generalised exponential integral. + E1: Special case of the generalised exponential integral. + li: Logarithmic integral. + Li: Offset logarithmic integral. + Si: Sine integral. + Ci: Cosine integral. + Shi: Hyperbolic sine integral. + Chi: Hyperbolic cosine integral. + uppergamma: Upper incomplete gamma function. + + References + ========== + + .. [1] https://dlmf.nist.gov/6.6 + .. [2] https://en.wikipedia.org/wiki/Exponential_integral + .. [3] Abramowitz & Stegun, section 5: https://web.archive.org/web/20201128173312/http://people.math.sfu.ca/~cbm/aands/page_228.htm + + """ + + + @classmethod + def eval(cls, z): + if z.is_zero: + return S.NegativeInfinity + elif z is S.Infinity: + return S.Infinity + elif z is S.NegativeInfinity: + return S.Zero + + if z.is_zero: + return S.NegativeInfinity + + nz, n = z.extract_branch_factor() + if n: + return Ei(nz) + 2*I*pi*n + + def fdiff(self, argindex=1): + arg = unpolarify(self.args[0]) + if argindex == 1: + return exp(arg)/arg + else: + raise ArgumentIndexError(self, argindex) + + def _eval_evalf(self, prec): + if (self.args[0]/polar_lift(-1)).is_positive: + return super()._eval_evalf(prec) + (I*pi)._eval_evalf(prec) + return super()._eval_evalf(prec) + + def _eval_rewrite_as_uppergamma(self, z, **kwargs): + from sympy.functions.special.gamma_functions import uppergamma + # XXX this does not currently work usefully because uppergamma + # immediately turns into expint + return -uppergamma(0, polar_lift(-1)*z) - I*pi + + def _eval_rewrite_as_expint(self, z, **kwargs): + return -expint(1, polar_lift(-1)*z) - I*pi + + def _eval_rewrite_as_li(self, z, **kwargs): + if isinstance(z, log): + return li(z.args[0]) + # TODO: + # Actually it only holds that: + # Ei(z) = li(exp(z)) + # for -pi < imag(z) <= pi + return li(exp(z)) + + def _eval_rewrite_as_Si(self, z, **kwargs): + if z.is_negative: + return Shi(z) + Chi(z) - I*pi + else: + return Shi(z) + Chi(z) + _eval_rewrite_as_Ci = _eval_rewrite_as_Si + _eval_rewrite_as_Chi = _eval_rewrite_as_Si + _eval_rewrite_as_Shi = _eval_rewrite_as_Si + + def _eval_rewrite_as_tractable(self, z, limitvar=None, **kwargs): + return exp(z) * _eis(z) + + def _eval_rewrite_as_Integral(self, z, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', [z]).name) + return Integral(S.Exp1**t/t, (t, S.NegativeInfinity, z)) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy import re + x0 = self.args[0].limit(x, 0) + arg = self.args[0].as_leading_term(x, cdir=cdir) + cdir = arg.dir(x, cdir) + if x0.is_zero: + c, e = arg.as_coeff_exponent(x) + logx = log(x) if logx is None else logx + return log(c) + e*logx + EulerGamma - ( + I*pi if re(cdir).is_negative else S.Zero) + return super()._eval_as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_nseries(self, x, n, logx, cdir=0): + x0 = self.args[0].limit(x, 0) + if x0.is_zero: + f = self._eval_rewrite_as_Si(*self.args) + return f._eval_nseries(x, n, logx) + return super()._eval_nseries(x, n, logx) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + point = args0[0] + + if point in (S.Infinity, S.NegativeInfinity): + z = self.args[0] + s = [factorial(k) / (z)**k for k in range(n)] + \ + [Order(1/z**n, x)] + return (exp(z)/z) * Add(*s) + + return super(Ei, self)._eval_aseries(n, args0, x, logx) + + +class expint(DefinedFunction): + r""" + Generalized exponential integral. + + Explanation + =========== + + This function is defined as + + .. math:: \operatorname{E}_\nu(z) = z^{\nu - 1} \Gamma(1 - \nu, z), + + where $\Gamma(1 - \nu, z)$ is the upper incomplete gamma function + (``uppergamma``). + + Hence for $z$ with positive real part we have + + .. math:: \operatorname{E}_\nu(z) + = \int_1^\infty \frac{e^{-zt}}{t^\nu} \mathrm{d}t, + + which explains the name. + + The representation as an incomplete gamma function provides an analytic + continuation for $\operatorname{E}_\nu(z)$. If $\nu$ is a + non-positive integer, the exponential integral is thus an unbranched + function of $z$, otherwise there is a branch point at the origin. + Refer to the incomplete gamma function documentation for details of the + branching behavior. + + Examples + ======== + + >>> from sympy import expint, S + >>> from sympy.abc import nu, z + + Differentiation is supported. Differentiation with respect to $z$ further + explains the name: for integral orders, the exponential integral is an + iterated integral of the exponential function. + + >>> expint(nu, z).diff(z) + -expint(nu - 1, z) + + Differentiation with respect to $\nu$ has no classical expression: + + >>> expint(nu, z).diff(nu) + -z**(nu - 1)*meijerg(((), (1, 1)), ((0, 0, 1 - nu), ()), z) + + At non-postive integer orders, the exponential integral reduces to the + exponential function: + + >>> expint(0, z) + exp(-z)/z + >>> expint(-1, z) + exp(-z)/z + exp(-z)/z**2 + + At half-integers it reduces to error functions: + + >>> expint(S(1)/2, z) + sqrt(pi)*erfc(sqrt(z))/sqrt(z) + + At positive integer orders it can be rewritten in terms of exponentials + and ``expint(1, z)``. Use ``expand_func()`` to do this: + + >>> from sympy import expand_func + >>> expand_func(expint(5, z)) + z**4*expint(1, z)/24 + (-z**3 + z**2 - 2*z + 6)*exp(-z)/24 + + The generalised exponential integral is essentially equivalent to the + incomplete gamma function: + + >>> from sympy import uppergamma + >>> expint(nu, z).rewrite(uppergamma) + z**(nu - 1)*uppergamma(1 - nu, z) + + As such it is branched at the origin: + + >>> from sympy import exp_polar, pi, I + >>> expint(4, z*exp_polar(2*pi*I)) + I*pi*z**3/3 + expint(4, z) + >>> expint(nu, z*exp_polar(2*pi*I)) + z**(nu - 1)*(exp(2*I*pi*nu) - 1)*gamma(1 - nu) + expint(nu, z) + + See Also + ======== + + Ei: Another related function called exponential integral. + E1: The classical case, returns expint(1, z). + li: Logarithmic integral. + Li: Offset logarithmic integral. + Si: Sine integral. + Ci: Cosine integral. + Shi: Hyperbolic sine integral. + Chi: Hyperbolic cosine integral. + uppergamma + + References + ========== + + .. [1] https://dlmf.nist.gov/8.19 + .. [2] https://functions.wolfram.com/GammaBetaErf/ExpIntegralE/ + .. [3] https://en.wikipedia.org/wiki/Exponential_integral + + """ + + + @classmethod + def eval(cls, nu, z): + from sympy.functions.special.gamma_functions import (gamma, uppergamma) + nu2 = unpolarify(nu) + if nu != nu2: + return expint(nu2, z) + if nu.is_Integer and nu <= 0 or (not nu.is_Integer and (2*nu).is_Integer): + return unpolarify(expand_mul(z**(nu - 1)*uppergamma(1 - nu, z))) + + # Extract branching information. This can be deduced from what is + # explained in lowergamma.eval(). + z, n = z.extract_branch_factor() + if n is S.Zero: + return + if nu.is_integer: + if not nu > 0: + return + return expint(nu, z) \ + - 2*pi*I*n*S.NegativeOne**(nu - 1)/factorial(nu - 1)*unpolarify(z)**(nu - 1) + else: + return (exp(2*I*pi*nu*n) - 1)*z**(nu - 1)*gamma(1 - nu) + expint(nu, z) + + def fdiff(self, argindex): + nu, z = self.args + if argindex == 1: + return -z**(nu - 1)*meijerg([], [1, 1], [0, 0, 1 - nu], [], z) + elif argindex == 2: + return -expint(nu - 1, z) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_uppergamma(self, nu, z, **kwargs): + from sympy.functions.special.gamma_functions import uppergamma + return z**(nu - 1)*uppergamma(1 - nu, z) + + def _eval_rewrite_as_Ei(self, nu, z, **kwargs): + if nu == 1: + return -Ei(z*exp_polar(-I*pi)) - I*pi + elif nu.is_Integer and nu > 1: + # DLMF, 8.19.7 + x = -unpolarify(z) + return x**(nu - 1)/factorial(nu - 1)*E1(z).rewrite(Ei) + \ + exp(x)/factorial(nu - 1) * \ + Add(*[factorial(nu - k - 2)*x**k for k in range(nu - 1)]) + else: + return self + + def _eval_expand_func(self, **hints): + return self.rewrite(Ei).rewrite(expint, **hints) + + def _eval_rewrite_as_Si(self, nu, z, **kwargs): + if nu != 1: + return self + return Shi(z) - Chi(z) + _eval_rewrite_as_Ci = _eval_rewrite_as_Si + _eval_rewrite_as_Chi = _eval_rewrite_as_Si + _eval_rewrite_as_Shi = _eval_rewrite_as_Si + + def _eval_nseries(self, x, n, logx, cdir=0): + if not self.args[0].has(x): + nu = self.args[0] + if nu == 1: + f = self._eval_rewrite_as_Si(*self.args) + return f._eval_nseries(x, n, logx) + elif nu.is_Integer and nu > 1: + f = self._eval_rewrite_as_Ei(*self.args) + return f._eval_nseries(x, n, logx) + return super()._eval_nseries(x, n, logx) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + point = args0[1] + nu = self.args[0] + + if point is S.Infinity: + z = self.args[1] + s = [S.NegativeOne**k * RisingFactorial(nu, k) / z**k for k in range(n)] + [Order(1/z**n, x)] + return (exp(-z)/z) * Add(*s) + + return super(expint, self)._eval_aseries(n, args0, x, logx) + + def _eval_rewrite_as_Integral(self, *args, **kwargs): + from sympy.integrals.integrals import Integral + n, x = self.args + t = Dummy(uniquely_named_symbol('t', args).name) + return Integral(t**-n * exp(-t*x), (t, 1, S.Infinity)) + + +def E1(z): + """ + Classical case of the generalized exponential integral. + + Explanation + =========== + + This is equivalent to ``expint(1, z)``. + + Examples + ======== + + >>> from sympy import E1 + >>> E1(0) + expint(1, 0) + + >>> E1(5) + expint(1, 5) + + See Also + ======== + + Ei: Exponential integral. + expint: Generalised exponential integral. + li: Logarithmic integral. + Li: Offset logarithmic integral. + Si: Sine integral. + Ci: Cosine integral. + Shi: Hyperbolic sine integral. + Chi: Hyperbolic cosine integral. + + """ + return expint(1, z) + + +class li(DefinedFunction): + r""" + The classical logarithmic integral. + + Explanation + =========== + + For use in SymPy, this function is defined as + + .. math:: \operatorname{li}(x) = \int_0^x \frac{1}{\log(t)} \mathrm{d}t \,. + + Examples + ======== + + >>> from sympy import I, oo, li + >>> from sympy.abc import z + + Several special values are known: + + >>> li(0) + 0 + >>> li(1) + -oo + >>> li(oo) + oo + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(li(z), z) + 1/log(z) + + Defining the ``li`` function via an integral: + >>> from sympy import integrate + >>> integrate(li(z)) + z*li(z) - Ei(2*log(z)) + + >>> integrate(li(z),z) + z*li(z) - Ei(2*log(z)) + + + The logarithmic integral can also be defined in terms of ``Ei``: + + >>> from sympy import Ei + >>> li(z).rewrite(Ei) + Ei(log(z)) + >>> diff(li(z).rewrite(Ei), z) + 1/log(z) + + We can numerically evaluate the logarithmic integral to arbitrary precision + on the whole complex plane (except the singular points): + + >>> li(2).evalf(30) + 1.04516378011749278484458888919 + + >>> li(2*I).evalf(30) + 1.0652795784357498247001125598 + 3.08346052231061726610939702133*I + + We can even compute Soldner's constant by the help of mpmath: + + >>> from mpmath import findroot + >>> findroot(li, 2) + 1.45136923488338 + + Further transformations include rewriting ``li`` in terms of + the trigonometric integrals ``Si``, ``Ci``, ``Shi`` and ``Chi``: + + >>> from sympy import Si, Ci, Shi, Chi + >>> li(z).rewrite(Si) + -log(I*log(z)) - log(1/log(z))/2 + log(log(z))/2 + Ci(I*log(z)) + Shi(log(z)) + >>> li(z).rewrite(Ci) + -log(I*log(z)) - log(1/log(z))/2 + log(log(z))/2 + Ci(I*log(z)) + Shi(log(z)) + >>> li(z).rewrite(Shi) + -log(1/log(z))/2 + log(log(z))/2 + Chi(log(z)) - Shi(log(z)) + >>> li(z).rewrite(Chi) + -log(1/log(z))/2 + log(log(z))/2 + Chi(log(z)) - Shi(log(z)) + + See Also + ======== + + Li: Offset logarithmic integral. + Ei: Exponential integral. + expint: Generalised exponential integral. + E1: Special case of the generalised exponential integral. + Si: Sine integral. + Ci: Cosine integral. + Shi: Hyperbolic sine integral. + Chi: Hyperbolic cosine integral. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Logarithmic_integral + .. [2] https://mathworld.wolfram.com/LogarithmicIntegral.html + .. [3] https://dlmf.nist.gov/6 + .. [4] https://mathworld.wolfram.com/SoldnersConstant.html + + """ + + + @classmethod + def eval(cls, z): + if z.is_zero: + return S.Zero + elif z is S.One: + return S.NegativeInfinity + elif z is S.Infinity: + return S.Infinity + if z.is_zero: + return S.Zero + + def fdiff(self, argindex=1): + arg = self.args[0] + if argindex == 1: + return S.One / log(arg) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_conjugate(self): + z = self.args[0] + # Exclude values on the branch cut (-oo, 0) + if not z.is_extended_negative: + return self.func(z.conjugate()) + + def _eval_rewrite_as_Li(self, z, **kwargs): + return Li(z) + li(2) + + def _eval_rewrite_as_Ei(self, z, **kwargs): + return Ei(log(z)) + + def _eval_rewrite_as_uppergamma(self, z, **kwargs): + from sympy.functions.special.gamma_functions import uppergamma + return (-uppergamma(0, -log(z)) + + S.Half*(log(log(z)) - log(S.One/log(z))) - log(-log(z))) + + def _eval_rewrite_as_Si(self, z, **kwargs): + return (Ci(I*log(z)) - I*Si(I*log(z)) - + S.Half*(log(S.One/log(z)) - log(log(z))) - log(I*log(z))) + + _eval_rewrite_as_Ci = _eval_rewrite_as_Si + + def _eval_rewrite_as_Shi(self, z, **kwargs): + return (Chi(log(z)) - Shi(log(z)) - S.Half*(log(S.One/log(z)) - log(log(z)))) + + _eval_rewrite_as_Chi = _eval_rewrite_as_Shi + + def _eval_rewrite_as_hyper(self, z, **kwargs): + return (log(z)*hyper((1, 1), (2, 2), log(z)) + + S.Half*(log(log(z)) - log(S.One/log(z))) + EulerGamma) + + def _eval_rewrite_as_meijerg(self, z, **kwargs): + return (-log(-log(z)) - S.Half*(log(S.One/log(z)) - log(log(z))) + - meijerg(((), (1,)), ((0, 0), ()), -log(z))) + + def _eval_rewrite_as_tractable(self, z, limitvar=None, **kwargs): + return z * _eis(log(z)) + + def _eval_nseries(self, x, n, logx, cdir=0): + z = self.args[0] + s = [(log(z))**k / (factorial(k) * k) for k in range(1, n)] + return EulerGamma + log(log(z)) + Add(*s) + + def _eval_is_zero(self): + z = self.args[0] + if z.is_zero: + return True + +class Li(DefinedFunction): + r""" + The offset logarithmic integral. + + Explanation + =========== + + For use in SymPy, this function is defined as + + .. math:: \operatorname{Li}(x) = \operatorname{li}(x) - \operatorname{li}(2) + + Examples + ======== + + >>> from sympy import Li + >>> from sympy.abc import z + + The following special value is known: + + >>> Li(2) + 0 + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(Li(z), z) + 1/log(z) + + The shifted logarithmic integral can be written in terms of $li(z)$: + + >>> from sympy import li + >>> Li(z).rewrite(li) + li(z) - li(2) + + We can numerically evaluate the logarithmic integral to arbitrary precision + on the whole complex plane (except the singular points): + + >>> Li(2).evalf(30) + 0 + + >>> Li(4).evalf(30) + 1.92242131492155809316615998938 + + See Also + ======== + + li: Logarithmic integral. + Ei: Exponential integral. + expint: Generalised exponential integral. + E1: Special case of the generalised exponential integral. + Si: Sine integral. + Ci: Cosine integral. + Shi: Hyperbolic sine integral. + Chi: Hyperbolic cosine integral. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Logarithmic_integral + .. [2] https://mathworld.wolfram.com/LogarithmicIntegral.html + .. [3] https://dlmf.nist.gov/6 + + """ + + + @classmethod + def eval(cls, z): + if z is S.Infinity: + return S.Infinity + elif z == S(2): + return S.Zero + + def fdiff(self, argindex=1): + arg = self.args[0] + if argindex == 1: + return S.One / log(arg) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_evalf(self, prec): + return self.rewrite(li).evalf(prec) + + def _eval_rewrite_as_li(self, z, **kwargs): + return li(z) - li(2) + + def _eval_rewrite_as_tractable(self, z, limitvar=None, **kwargs): + return self.rewrite(li).rewrite("tractable", deep=True) + + def _eval_nseries(self, x, n, logx, cdir=0): + f = self._eval_rewrite_as_li(*self.args) + return f._eval_nseries(x, n, logx) + +############################################################################### +#################### TRIGONOMETRIC INTEGRALS ################################## +############################################################################### + +class TrigonometricIntegral(DefinedFunction): + """ Base class for trigonometric integrals. """ + + + @classmethod + def eval(cls, z): + if z is S.Zero: + return cls._atzero + elif z is S.Infinity: + return cls._atinf() + elif z is S.NegativeInfinity: + return cls._atneginf() + + if z.is_zero: + return cls._atzero + + nz = z.extract_multiplicatively(polar_lift(I)) + if nz is None and cls._trigfunc(0) == 0: + nz = z.extract_multiplicatively(I) + if nz is not None: + return cls._Ifactor(nz, 1) + nz = z.extract_multiplicatively(polar_lift(-I)) + if nz is not None: + return cls._Ifactor(nz, -1) + + nz = z.extract_multiplicatively(polar_lift(-1)) + if nz is None and cls._trigfunc(0) == 0: + nz = z.extract_multiplicatively(-1) + if nz is not None: + return cls._minusfactor(nz) + + nz, n = z.extract_branch_factor() + if n == 0 and nz == z: + return + return 2*pi*I*n*cls._trigfunc(0) + cls(nz) + + def fdiff(self, argindex=1): + arg = unpolarify(self.args[0]) + if argindex == 1: + return self._trigfunc(arg)/arg + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Ei(self, z, **kwargs): + return self._eval_rewrite_as_expint(z).rewrite(Ei) + + def _eval_rewrite_as_uppergamma(self, z, **kwargs): + from sympy.functions.special.gamma_functions import uppergamma + return self._eval_rewrite_as_expint(z).rewrite(uppergamma) + + def _eval_nseries(self, x, n, logx, cdir=0): + # NOTE this is fairly inefficient + if self.args[0].subs(x, 0) != 0: + return super()._eval_nseries(x, n, logx) + baseseries = self._trigfunc(x)._eval_nseries(x, n, logx) + if self._trigfunc(0) != 0: + baseseries -= 1 + baseseries = baseseries.replace(Pow, lambda t, n: t**n/n, simultaneous=False) + if self._trigfunc(0) != 0: + baseseries += EulerGamma + log(x) + return baseseries.subs(x, self.args[0])._eval_nseries(x, n, logx) + + +class Si(TrigonometricIntegral): + r""" + Sine integral. + + Explanation + =========== + + This function is defined by + + .. math:: \operatorname{Si}(z) = \int_0^z \frac{\sin{t}}{t} \mathrm{d}t. + + It is an entire function. + + Examples + ======== + + >>> from sympy import Si + >>> from sympy.abc import z + + The sine integral is an antiderivative of $sin(z)/z$: + + >>> Si(z).diff(z) + sin(z)/z + + It is unbranched: + + >>> from sympy import exp_polar, I, pi + >>> Si(z*exp_polar(2*I*pi)) + Si(z) + + Sine integral behaves much like ordinary sine under multiplication by ``I``: + + >>> Si(I*z) + I*Shi(z) + >>> Si(-z) + -Si(z) + + It can also be expressed in terms of exponential integrals, but beware + that the latter is branched: + + >>> from sympy import expint + >>> Si(z).rewrite(expint) + -I*(-expint(1, z*exp_polar(-I*pi/2))/2 + + expint(1, z*exp_polar(I*pi/2))/2) + pi/2 + + It can be rewritten in the form of sinc function (by definition): + + >>> from sympy import sinc + >>> Si(z).rewrite(sinc) + Integral(sinc(_t), (_t, 0, z)) + + See Also + ======== + + Ci: Cosine integral. + Shi: Hyperbolic sine integral. + Chi: Hyperbolic cosine integral. + Ei: Exponential integral. + expint: Generalised exponential integral. + sinc: unnormalized sinc function + E1: Special case of the generalised exponential integral. + li: Logarithmic integral. + Li: Offset logarithmic integral. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_integral + + """ + + _trigfunc = sin + _atzero = S.Zero + + @classmethod + def _atinf(cls): + return pi*S.Half + + @classmethod + def _atneginf(cls): + return -pi*S.Half + + @classmethod + def _minusfactor(cls, z): + return -Si(z) + + @classmethod + def _Ifactor(cls, z, sign): + return I*Shi(z)*sign + + def _eval_rewrite_as_expint(self, z, **kwargs): + # XXX should we polarify z? + return pi/2 + (E1(polar_lift(I)*z) - E1(polar_lift(-I)*z))/2/I + + def _eval_rewrite_as_Integral(self, z, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', [z]).name) + return Integral(sinc(t), (t, 0, z)) + + _eval_rewrite_as_sinc = _eval_rewrite_as_Integral + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if arg0 is S.NaN: + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if arg0.is_zero: + return arg + elif not arg0.is_infinite: + return self.func(arg0) + else: + return self + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + point = args0[0] + + # Expansion at oo + if point is S.Infinity: + z = self.args[0] + p = [S.NegativeOne**k * factorial(2*k) / z**(2*k + 1) + for k in range(n//2 + 1)] + [Order(1/z**n, x)] + q = [S.NegativeOne**k * factorial(2*k + 1) / z**(2*(k + 1)) + for k in range(n//2)] + [Order(1/z**n, x)] + return pi/2 - cos(z)*Add(*p) - sin(z)*Add(*q) + + # All other points are not handled + return super(Si, self)._eval_aseries(n, args0, x, logx) + + def _eval_is_zero(self): + z = self.args[0] + if z.is_zero: + return True + + +class Ci(TrigonometricIntegral): + r""" + Cosine integral. + + Explanation + =========== + + This function is defined for positive $x$ by + + .. math:: \operatorname{Ci}(x) = \gamma + \log{x} + + \int_0^x \frac{\cos{t} - 1}{t} \mathrm{d}t + = -\int_x^\infty \frac{\cos{t}}{t} \mathrm{d}t, + + where $\gamma$ is the Euler-Mascheroni constant. + + We have + + .. math:: \operatorname{Ci}(z) = + -\frac{\operatorname{E}_1\left(e^{i\pi/2} z\right) + + \operatorname{E}_1\left(e^{-i \pi/2} z\right)}{2} + + which holds for all polar $z$ and thus provides an analytic + continuation to the Riemann surface of the logarithm. + + The formula also holds as stated + for $z \in \mathbb{C}$ with $\Re(z) > 0$. + By lifting to the principal branch, we obtain an analytic function on the + cut complex plane. + + Examples + ======== + + >>> from sympy import Ci + >>> from sympy.abc import z + + The cosine integral is a primitive of $\cos(z)/z$: + + >>> Ci(z).diff(z) + cos(z)/z + + It has a logarithmic branch point at the origin: + + >>> from sympy import exp_polar, I, pi + >>> Ci(z*exp_polar(2*I*pi)) + Ci(z) + 2*I*pi + + The cosine integral behaves somewhat like ordinary $\cos$ under + multiplication by $i$: + + >>> from sympy import polar_lift + >>> Ci(polar_lift(I)*z) + Chi(z) + I*pi/2 + >>> Ci(polar_lift(-1)*z) + Ci(z) + I*pi + + It can also be expressed in terms of exponential integrals: + + >>> from sympy import expint + >>> Ci(z).rewrite(expint) + -expint(1, z*exp_polar(-I*pi/2))/2 - expint(1, z*exp_polar(I*pi/2))/2 + + See Also + ======== + + Si: Sine integral. + Shi: Hyperbolic sine integral. + Chi: Hyperbolic cosine integral. + Ei: Exponential integral. + expint: Generalised exponential integral. + E1: Special case of the generalised exponential integral. + li: Logarithmic integral. + Li: Offset logarithmic integral. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_integral + + """ + + _trigfunc = cos + _atzero = S.ComplexInfinity + + @classmethod + def _atinf(cls): + return S.Zero + + @classmethod + def _atneginf(cls): + return I*pi + + @classmethod + def _minusfactor(cls, z): + return Ci(z) + I*pi + + @classmethod + def _Ifactor(cls, z, sign): + return Chi(z) + I*pi/2*sign + + def _eval_rewrite_as_expint(self, z, **kwargs): + return -(E1(polar_lift(I)*z) + E1(polar_lift(-I)*z))/2 + + def _eval_rewrite_as_Integral(self, z, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', [z]).name) + return S.EulerGamma + log(z) - Integral((1-cos(t))/t, (t, 0, z)) + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if arg0 is S.NaN: + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if arg0.is_zero: + c, e = arg.as_coeff_exponent(x) + logx = log(x) if logx is None else logx + return log(c) + e*logx + EulerGamma + elif arg0.is_finite: + return self.func(arg0) + else: + return self + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + point = args0[0] + + if point in (S.Infinity, S.NegativeInfinity): + z = self.args[0] + p = [S.NegativeOne**k * factorial(2*k) / z**(2*k + 1) + for k in range(n//2 + 1)] + [Order(1/z**n, x)] + q = [S.NegativeOne**k * factorial(2*k + 1) / z**(2*(k + 1)) + for k in range(n//2)] + [Order(1/z**n, x)] + result = sin(z)*(Add(*p)) - cos(z)*(Add(*q)) + + if point is S.NegativeInfinity: + result += I*pi + return result + + return super(Ci, self)._eval_aseries(n, args0, x, logx) + +class Shi(TrigonometricIntegral): + r""" + Sinh integral. + + Explanation + =========== + + This function is defined by + + .. math:: \operatorname{Shi}(z) = \int_0^z \frac{\sinh{t}}{t} \mathrm{d}t. + + It is an entire function. + + Examples + ======== + + >>> from sympy import Shi + >>> from sympy.abc import z + + The Sinh integral is a primitive of $\sinh(z)/z$: + + >>> Shi(z).diff(z) + sinh(z)/z + + It is unbranched: + + >>> from sympy import exp_polar, I, pi + >>> Shi(z*exp_polar(2*I*pi)) + Shi(z) + + The $\sinh$ integral behaves much like ordinary $\sinh$ under + multiplication by $i$: + + >>> Shi(I*z) + I*Si(z) + >>> Shi(-z) + -Shi(z) + + It can also be expressed in terms of exponential integrals, but beware + that the latter is branched: + + >>> from sympy import expint + >>> Shi(z).rewrite(expint) + expint(1, z)/2 - expint(1, z*exp_polar(I*pi))/2 - I*pi/2 + + See Also + ======== + + Si: Sine integral. + Ci: Cosine integral. + Chi: Hyperbolic cosine integral. + Ei: Exponential integral. + expint: Generalised exponential integral. + E1: Special case of the generalised exponential integral. + li: Logarithmic integral. + Li: Offset logarithmic integral. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_integral + + """ + + _trigfunc = sinh + _atzero = S.Zero + + @classmethod + def _atinf(cls): + return S.Infinity + + @classmethod + def _atneginf(cls): + return S.NegativeInfinity + + @classmethod + def _minusfactor(cls, z): + return -Shi(z) + + @classmethod + def _Ifactor(cls, z, sign): + return I*Si(z)*sign + + def _eval_rewrite_as_expint(self, z, **kwargs): + # XXX should we polarify z? + return (E1(z) - E1(exp_polar(I*pi)*z))/2 - I*pi/2 + + def _eval_is_zero(self): + z = self.args[0] + if z.is_zero: + return True + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x) + arg0 = arg.subs(x, 0) + + if arg0 is S.NaN: + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if arg0.is_zero: + return arg + elif not arg0.is_infinite: + return self.func(arg0) + else: + return self + + +class Chi(TrigonometricIntegral): + r""" + Cosh integral. + + Explanation + =========== + + This function is defined for positive $x$ by + + .. math:: \operatorname{Chi}(x) = \gamma + \log{x} + + \int_0^x \frac{\cosh{t} - 1}{t} \mathrm{d}t, + + where $\gamma$ is the Euler-Mascheroni constant. + + We have + + .. math:: \operatorname{Chi}(z) = \operatorname{Ci}\left(e^{i \pi/2}z\right) + - i\frac{\pi}{2}, + + which holds for all polar $z$ and thus provides an analytic + continuation to the Riemann surface of the logarithm. + By lifting to the principal branch we obtain an analytic function on the + cut complex plane. + + Examples + ======== + + >>> from sympy import Chi + >>> from sympy.abc import z + + The $\cosh$ integral is a primitive of $\cosh(z)/z$: + + >>> Chi(z).diff(z) + cosh(z)/z + + It has a logarithmic branch point at the origin: + + >>> from sympy import exp_polar, I, pi + >>> Chi(z*exp_polar(2*I*pi)) + Chi(z) + 2*I*pi + + The $\cosh$ integral behaves somewhat like ordinary $\cosh$ under + multiplication by $i$: + + >>> from sympy import polar_lift + >>> Chi(polar_lift(I)*z) + Ci(z) + I*pi/2 + >>> Chi(polar_lift(-1)*z) + Chi(z) + I*pi + + It can also be expressed in terms of exponential integrals: + + >>> from sympy import expint + >>> Chi(z).rewrite(expint) + -expint(1, z)/2 - expint(1, z*exp_polar(I*pi))/2 - I*pi/2 + + See Also + ======== + + Si: Sine integral. + Ci: Cosine integral. + Shi: Hyperbolic sine integral. + Ei: Exponential integral. + expint: Generalised exponential integral. + E1: Special case of the generalised exponential integral. + li: Logarithmic integral. + Li: Offset logarithmic integral. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigonometric_integral + + """ + + _trigfunc = cosh + _atzero = S.ComplexInfinity + + @classmethod + def _atinf(cls): + return S.Infinity + + @classmethod + def _atneginf(cls): + return S.Infinity + + @classmethod + def _minusfactor(cls, z): + return Chi(z) + I*pi + + @classmethod + def _Ifactor(cls, z, sign): + return Ci(z) + I*pi/2*sign + + def _eval_rewrite_as_expint(self, z, **kwargs): + return -I*pi/2 - (E1(z) + E1(exp_polar(I*pi)*z))/2 + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if arg0 is S.NaN: + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if arg0.is_zero: + c, e = arg.as_coeff_exponent(x) + logx = log(x) if logx is None else logx + return log(c) + e*logx + EulerGamma + elif arg0.is_finite: + return self.func(arg0) + else: + return self + + +############################################################################### +#################### FRESNEL INTEGRALS ######################################## +############################################################################### + +class FresnelIntegral(DefinedFunction): + """ Base class for the Fresnel integrals.""" + + unbranched = True + + @classmethod + def eval(cls, z): + # Values at positive infinities signs + # if any were extracted automatically + if z is S.Infinity: + return S.Half + + # Value at zero + if z.is_zero: + return S.Zero + + # Try to pull out factors of -1 and I + prefact = S.One + newarg = z + changed = False + + nz = newarg.extract_multiplicatively(-1) + if nz is not None: + prefact = -prefact + newarg = nz + changed = True + + nz = newarg.extract_multiplicatively(I) + if nz is not None: + prefact = cls._sign*I*prefact + newarg = nz + changed = True + + if changed: + return prefact*cls(newarg) + + def fdiff(self, argindex=1): + if argindex == 1: + return self._trigfunc(S.Half*pi*self.args[0]**2) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_is_extended_real(self): + return self.args[0].is_extended_real + + _eval_is_finite = _eval_is_extended_real + + def _eval_is_zero(self): + return self.args[0].is_zero + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + as_real_imag = real_to_real_as_real_imag + + +class fresnels(FresnelIntegral): + r""" + Fresnel integral S. + + Explanation + =========== + + This function is defined by + + .. math:: \operatorname{S}(z) = \int_0^z \sin{\frac{\pi}{2} t^2} \mathrm{d}t. + + It is an entire function. + + Examples + ======== + + >>> from sympy import I, oo, fresnels + >>> from sympy.abc import z + + Several special values are known: + + >>> fresnels(0) + 0 + >>> fresnels(oo) + 1/2 + >>> fresnels(-oo) + -1/2 + >>> fresnels(I*oo) + -I/2 + >>> fresnels(-I*oo) + I/2 + + In general one can pull out factors of -1 and $i$ from the argument: + + >>> fresnels(-z) + -fresnels(z) + >>> fresnels(I*z) + -I*fresnels(z) + + The Fresnel S integral obeys the mirror symmetry + $\overline{S(z)} = S(\bar{z})$: + + >>> from sympy import conjugate + >>> conjugate(fresnels(z)) + fresnels(conjugate(z)) + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(fresnels(z), z) + sin(pi*z**2/2) + + Defining the Fresnel functions via an integral: + + >>> from sympy import integrate, pi, sin, expand_func + >>> integrate(sin(pi*z**2/2), z) + 3*fresnels(z)*gamma(3/4)/(4*gamma(7/4)) + >>> expand_func(integrate(sin(pi*z**2/2), z)) + fresnels(z) + + We can numerically evaluate the Fresnel integral to arbitrary precision + on the whole complex plane: + + >>> fresnels(2).evalf(30) + 0.343415678363698242195300815958 + + >>> fresnels(-2*I).evalf(30) + 0.343415678363698242195300815958*I + + See Also + ======== + + fresnelc: Fresnel cosine integral. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Fresnel_integral + .. [2] https://dlmf.nist.gov/7 + .. [3] https://mathworld.wolfram.com/FresnelIntegrals.html + .. [4] https://functions.wolfram.com/GammaBetaErf/FresnelS + .. [5] The converging factors for the fresnel integrals + by John W. Wrench Jr. and Vicki Alley + + """ + _trigfunc = sin + _sign = -S.One + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) > 1: + p = previous_terms[-1] + return (-pi**2*x**4*(4*n - 1)/(8*n*(2*n + 1)*(4*n + 3))) * p + else: + return x**3 * (-x**4)**n * (S(2)**(-2*n - 1)*pi**(2*n + 1)) / ((4*n + 3)*factorial(2*n + 1)) + + def _eval_rewrite_as_erf(self, z, **kwargs): + return (S.One + I)/4 * (erf((S.One + I)/2*sqrt(pi)*z) - I*erf((S.One - I)/2*sqrt(pi)*z)) + + def _eval_rewrite_as_hyper(self, z, **kwargs): + return pi*z**3/6 * hyper([Rational(3, 4)], [Rational(3, 2), Rational(7, 4)], -pi**2*z**4/16) + + def _eval_rewrite_as_meijerg(self, z, **kwargs): + return (pi*z**Rational(9, 4) / (sqrt(2)*(z**2)**Rational(3, 4)*(-z)**Rational(3, 4)) + * meijerg([], [1], [Rational(3, 4)], [Rational(1, 4), 0], -pi**2*z**4/16)) + + def _eval_rewrite_as_Integral(self, z, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', [z]).name) + return Integral(sin(pi*t**2/2), (t, 0, z)) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.series.order import Order + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if arg0 is S.ComplexInfinity: + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if arg0.is_zero: + return pi*arg**3/6 + elif arg0 in [S.Infinity, S.NegativeInfinity]: + s = 1 if arg0 is S.Infinity else -1 + return s*S.Half + Order(x, x) + else: + return self.func(arg0) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + point = args0[0] + + # Expansion at oo and -oo + if point in [S.Infinity, -S.Infinity]: + z = self.args[0] + + # expansion of S(x) = S1(x*sqrt(pi/2)), see reference[5] page 1-8 + # as only real infinities are dealt with, sin and cos are O(1) + p = [S.NegativeOne**k * factorial(4*k + 1) / + (2**(2*k + 2) * z**(4*k + 3) * 2**(2*k)*factorial(2*k)) + for k in range(0, n) if 4*k + 3 < n] + q = [1/(2*z)] + [S.NegativeOne**k * factorial(4*k - 1) / + (2**(2*k + 1) * z**(4*k + 1) * 2**(2*k - 1)*factorial(2*k - 1)) + for k in range(1, n) if 4*k + 1 < n] + + p = [-sqrt(2/pi)*t for t in p] + q = [-sqrt(2/pi)*t for t in q] + s = 1 if point is S.Infinity else -1 + # The expansion at oo is 1/2 + some odd powers of z + # To get the expansion at -oo, replace z by -z and flip the sign + # The result -1/2 + the same odd powers of z as before. + return s*S.Half + (sin(z**2)*Add(*p) + cos(z**2)*Add(*q) + ).subs(x, sqrt(2/pi)*x) + Order(1/z**n, x) + + # All other points are not handled + return super()._eval_aseries(n, args0, x, logx) + + +class fresnelc(FresnelIntegral): + r""" + Fresnel integral C. + + Explanation + =========== + + This function is defined by + + .. math:: \operatorname{C}(z) = \int_0^z \cos{\frac{\pi}{2} t^2} \mathrm{d}t. + + It is an entire function. + + Examples + ======== + + >>> from sympy import I, oo, fresnelc + >>> from sympy.abc import z + + Several special values are known: + + >>> fresnelc(0) + 0 + >>> fresnelc(oo) + 1/2 + >>> fresnelc(-oo) + -1/2 + >>> fresnelc(I*oo) + I/2 + >>> fresnelc(-I*oo) + -I/2 + + In general one can pull out factors of -1 and $i$ from the argument: + + >>> fresnelc(-z) + -fresnelc(z) + >>> fresnelc(I*z) + I*fresnelc(z) + + The Fresnel C integral obeys the mirror symmetry + $\overline{C(z)} = C(\bar{z})$: + + >>> from sympy import conjugate + >>> conjugate(fresnelc(z)) + fresnelc(conjugate(z)) + + Differentiation with respect to $z$ is supported: + + >>> from sympy import diff + >>> diff(fresnelc(z), z) + cos(pi*z**2/2) + + Defining the Fresnel functions via an integral: + + >>> from sympy import integrate, pi, cos, expand_func + >>> integrate(cos(pi*z**2/2), z) + fresnelc(z)*gamma(1/4)/(4*gamma(5/4)) + >>> expand_func(integrate(cos(pi*z**2/2), z)) + fresnelc(z) + + We can numerically evaluate the Fresnel integral to arbitrary precision + on the whole complex plane: + + >>> fresnelc(2).evalf(30) + 0.488253406075340754500223503357 + + >>> fresnelc(-2*I).evalf(30) + -0.488253406075340754500223503357*I + + See Also + ======== + + fresnels: Fresnel sine integral. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Fresnel_integral + .. [2] https://dlmf.nist.gov/7 + .. [3] https://mathworld.wolfram.com/FresnelIntegrals.html + .. [4] https://functions.wolfram.com/GammaBetaErf/FresnelC + .. [5] The converging factors for the fresnel integrals + by John W. Wrench Jr. and Vicki Alley + + """ + _trigfunc = cos + _sign = S.One + + @staticmethod + @cacheit + def taylor_term(n, x, *previous_terms): + if n < 0: + return S.Zero + else: + x = sympify(x) + if len(previous_terms) > 1: + p = previous_terms[-1] + return (-pi**2*x**4*(4*n - 3)/(8*n*(2*n - 1)*(4*n + 1))) * p + else: + return x * (-x**4)**n * (S(2)**(-2*n)*pi**(2*n)) / ((4*n + 1)*factorial(2*n)) + + def _eval_rewrite_as_erf(self, z, **kwargs): + return (S.One - I)/4 * (erf((S.One + I)/2*sqrt(pi)*z) + I*erf((S.One - I)/2*sqrt(pi)*z)) + + def _eval_rewrite_as_hyper(self, z, **kwargs): + return z * hyper([Rational(1, 4)], [S.Half, Rational(5, 4)], -pi**2*z**4/16) + + def _eval_rewrite_as_meijerg(self, z, **kwargs): + return (pi*z**Rational(3, 4) / (sqrt(2)*root(z**2, 4)*root(-z, 4)) + * meijerg([], [1], [Rational(1, 4)], [Rational(3, 4), 0], -pi**2*z**4/16)) + + def _eval_rewrite_as_Integral(self, z, **kwargs): + from sympy.integrals.integrals import Integral + t = Dummy(uniquely_named_symbol('t', [z]).name) + return Integral(cos(pi*t**2/2), (t, 0, z)) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.series.order import Order + arg = self.args[0].as_leading_term(x, logx=logx, cdir=cdir) + arg0 = arg.subs(x, 0) + + if arg0 is S.ComplexInfinity: + arg0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + if arg0.is_zero: + return arg + elif arg0 in [S.Infinity, S.NegativeInfinity]: + s = 1 if arg0 is S.Infinity else -1 + return s*S.Half + Order(x, x) + else: + return self.func(arg0) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + point = args0[0] + + # Expansion at oo + if point in [S.Infinity, -S.Infinity]: + z = self.args[0] + + # expansion of C(x) = C1(x*sqrt(pi/2)), see reference[5] page 1-8 + # as only real infinities are dealt with, sin and cos are O(1) + p = [S.NegativeOne**k * factorial(4*k + 1) / + (2**(2*k + 2) * z**(4*k + 3) * 2**(2*k)*factorial(2*k)) + for k in range(n) if 4*k + 3 < n] + q = [1/(2*z)] + [S.NegativeOne**k * factorial(4*k - 1) / + (2**(2*k + 1) * z**(4*k + 1) * 2**(2*k - 1)*factorial(2*k - 1)) + for k in range(1, n) if 4*k + 1 < n] + + p = [-sqrt(2/pi)*t for t in p] + q = [ sqrt(2/pi)*t for t in q] + s = 1 if point is S.Infinity else -1 + # The expansion at oo is 1/2 + some odd powers of z + # To get the expansion at -oo, replace z by -z and flip the sign + # The result -1/2 + the same odd powers of z as before. + return s*S.Half + (cos(z**2)*Add(*p) + sin(z**2)*Add(*q) + ).subs(x, sqrt(2/pi)*x) + Order(1/z**n, x) + + # All other points are not handled + return super()._eval_aseries(n, args0, x, logx) + + +############################################################################### +#################### HELPER FUNCTIONS ######################################### +############################################################################### + + +class _erfs(DefinedFunction): + """ + Helper function to make the $\\mathrm{erf}(z)$ function + tractable for the Gruntz algorithm. + + """ + @classmethod + def eval(cls, arg): + if arg.is_zero: + return S.One + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + point = args0[0] + + # Expansion at oo + if point is S.Infinity: + z = self.args[0] + l = [1/sqrt(pi) * factorial(2*k)*(-S( + 4))**(-k)/factorial(k) * (1/z)**(2*k + 1) for k in range(n)] + o = Order(1/z**(2*n + 1), x) + # It is very inefficient to first add the order and then do the nseries + return (Add(*l))._eval_nseries(x, n, logx) + o + + # Expansion at I*oo + t = point.extract_multiplicatively(I) + if t is S.Infinity: + z = self.args[0] + # TODO: is the series really correct? + l = [1/sqrt(pi) * factorial(2*k)*(-S( + 4))**(-k)/factorial(k) * (1/z)**(2*k + 1) for k in range(n)] + o = Order(1/z**(2*n + 1), x) + # It is very inefficient to first add the order and then do the nseries + return (Add(*l))._eval_nseries(x, n, logx) + o + + # All other points are not handled + return super()._eval_aseries(n, args0, x, logx) + + def fdiff(self, argindex=1): + if argindex == 1: + z = self.args[0] + return -2/sqrt(pi) + 2*z*_erfs(z) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_intractable(self, z, **kwargs): + return (S.One - erf(z))*exp(z**2) + + +class _eis(DefinedFunction): + """ + Helper function to make the $\\mathrm{Ei}(z)$ and $\\mathrm{li}(z)$ + functions tractable for the Gruntz algorithm. + + """ + + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + if args0[0] not in (S.Infinity, S.NegativeInfinity): + return super()._eval_aseries(n, args0, x, logx) + + z = self.args[0] + l = [factorial(k) * (1/z)**(k + 1) for k in range(n)] + o = Order(1/z**(n + 1), x) + # It is very inefficient to first add the order and then do the nseries + return (Add(*l))._eval_nseries(x, n, logx) + o + + + def fdiff(self, argindex=1): + if argindex == 1: + z = self.args[0] + return S.One / z - _eis(z) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_intractable(self, z, **kwargs): + return exp(-z)*Ei(z) + + def _eval_as_leading_term(self, x, logx, cdir): + x0 = self.args[0].limit(x, 0) + if x0.is_zero: + f = self._eval_rewrite_as_intractable(*self.args) + return f._eval_as_leading_term(x, logx=logx, cdir=cdir) + return super()._eval_as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_nseries(self, x, n, logx, cdir=0): + x0 = self.args[0].limit(x, 0) + if x0.is_zero: + f = self._eval_rewrite_as_intractable(*self.args) + return f._eval_nseries(x, n, logx) + return super()._eval_nseries(x, n, logx) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/gamma_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/gamma_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..73a5a1585154c603e9c510b3c61144039e0e5502 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/gamma_functions.py @@ -0,0 +1,1344 @@ +from math import prod + +from sympy.core import Add, S, Dummy, expand_func +from sympy.core.expr import Expr +from sympy.core.function import DefinedFunction, ArgumentIndexError, PoleError +from sympy.core.logic import fuzzy_and, fuzzy_not +from sympy.core.numbers import Rational, pi, oo, I +from sympy.core.power import Pow +from sympy.functions.special.zeta_functions import zeta +from sympy.functions.special.error_functions import erf, erfc, Ei +from sympy.functions.elementary.complexes import re, unpolarify +from sympy.functions.elementary.exponential import exp, log +from sympy.functions.elementary.integers import ceiling, floor +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import sin, cos, cot +from sympy.functions.combinatorial.numbers import bernoulli, harmonic +from sympy.functions.combinatorial.factorials import factorial, rf, RisingFactorial +from sympy.utilities.misc import as_int + +from mpmath import mp, workprec +from mpmath.libmp.libmpf import prec_to_dps + +def intlike(n): + try: + as_int(n, strict=False) + return True + except ValueError: + return False + +############################################################################### +############################ COMPLETE GAMMA FUNCTION ########################## +############################################################################### + +class gamma(DefinedFunction): + r""" + The gamma function + + .. math:: + \Gamma(x) := \int^{\infty}_{0} t^{x-1} e^{-t} \mathrm{d}t. + + Explanation + =========== + + The ``gamma`` function implements the function which passes through the + values of the factorial function (i.e., $\Gamma(n) = (n - 1)!$ when n is + an integer). More generally, $\Gamma(z)$ is defined in the whole complex + plane except at the negative integers where there are simple poles. + + Examples + ======== + + >>> from sympy import S, I, pi, gamma + >>> from sympy.abc import x + + Several special values are known: + + >>> gamma(1) + 1 + >>> gamma(4) + 6 + >>> gamma(S(3)/2) + sqrt(pi)/2 + + The ``gamma`` function obeys the mirror symmetry: + + >>> from sympy import conjugate + >>> conjugate(gamma(x)) + gamma(conjugate(x)) + + Differentiation with respect to $x$ is supported: + + >>> from sympy import diff + >>> diff(gamma(x), x) + gamma(x)*polygamma(0, x) + + Series expansion is also supported: + + >>> from sympy import series + >>> series(gamma(x), x, 0, 3) + 1/x - EulerGamma + x*(EulerGamma**2/2 + pi**2/12) + x**2*(-EulerGamma*pi**2/12 - zeta(3)/3 - EulerGamma**3/6) + O(x**3) + + We can numerically evaluate the ``gamma`` function to arbitrary precision + on the whole complex plane: + + >>> gamma(pi).evalf(40) + 2.288037795340032417959588909060233922890 + >>> gamma(1+I).evalf(20) + 0.49801566811835604271 - 0.15494982830181068512*I + + See Also + ======== + + lowergamma: Lower incomplete gamma function. + uppergamma: Upper incomplete gamma function. + polygamma: Polygamma function. + loggamma: Log Gamma function. + digamma: Digamma function. + trigamma: Trigamma function. + sympy.functions.special.beta_functions.beta: Euler Beta function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gamma_function + .. [2] https://dlmf.nist.gov/5 + .. [3] https://mathworld.wolfram.com/GammaFunction.html + .. [4] https://functions.wolfram.com/GammaBetaErf/Gamma/ + + """ + + unbranched = True + _singularities = (S.ComplexInfinity,) + + def fdiff(self, argindex=1): + if argindex == 1: + return self.func(self.args[0])*polygamma(0, self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, arg): + if arg.is_Number: + if arg is S.NaN: + return S.NaN + elif arg is oo: + return oo + elif intlike(arg): + if arg.is_positive: + return factorial(arg - 1) + else: + return S.ComplexInfinity + elif arg.is_Rational: + if arg.q == 2: + n = abs(arg.p) // arg.q + + if arg.is_positive: + k, coeff = n, S.One + else: + n = k = n + 1 + + if n & 1 == 0: + coeff = S.One + else: + coeff = S.NegativeOne + + coeff *= prod(range(3, 2*k, 2)) + + if arg.is_positive: + return coeff*sqrt(pi) / 2**n + else: + return 2**n*sqrt(pi) / coeff + + def _eval_expand_func(self, **hints): + arg = self.args[0] + if arg.is_Rational: + if abs(arg.p) > arg.q: + x = Dummy('x') + n = arg.p // arg.q + p = arg.p - n*arg.q + return self.func(x + n)._eval_expand_func().subs(x, Rational(p, arg.q)) + + if arg.is_Add: + coeff, tail = arg.as_coeff_add() + if coeff and coeff.q != 1: + intpart = floor(coeff) + tail = (coeff - intpart,) + tail + coeff = intpart + tail = arg._new_rawargs(*tail, reeval=False) + return self.func(tail)*RisingFactorial(tail, coeff) + + return self.func(*self.args) + + def _eval_conjugate(self): + return self.func(self.args[0].conjugate()) + + def _eval_is_real(self): + x = self.args[0] + if x.is_nonpositive and x.is_integer: + return False + if intlike(x) and x <= 0: + return False + if x.is_positive or x.is_noninteger: + return True + + def _eval_is_positive(self): + x = self.args[0] + if x.is_positive: + return True + elif x.is_noninteger: + return floor(x).is_even + + def _eval_rewrite_as_tractable(self, z, limitvar=None, **kwargs): + return exp(loggamma(z)) + + def _eval_rewrite_as_factorial(self, z, **kwargs): + return factorial(z - 1) + + def _eval_nseries(self, x, n, logx, cdir=0): + x0 = self.args[0].limit(x, 0) + if not (x0.is_Integer and x0 <= 0): + return super()._eval_nseries(x, n, logx) + t = self.args[0] - x0 + return (self.func(t + 1)/rf(self.args[0], -x0 + 1))._eval_nseries(x, n, logx) + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[0] + x0 = arg.subs(x, 0) + + if x0.is_integer and x0.is_nonpositive: + n = -x0 + res = S.NegativeOne**n/self.func(n + 1) + return res/(arg + n).as_leading_term(x) + elif not x0.is_infinite: + return self.func(x0) + raise PoleError() + + +############################################################################### +################## LOWER and UPPER INCOMPLETE GAMMA FUNCTIONS ################# +############################################################################### + +class lowergamma(DefinedFunction): + r""" + The lower incomplete gamma function. + + Explanation + =========== + + It can be defined as the meromorphic continuation of + + .. math:: + \gamma(s, x) := \int_0^x t^{s-1} e^{-t} \mathrm{d}t = \Gamma(s) - \Gamma(s, x). + + This can be shown to be the same as + + .. math:: + \gamma(s, x) = \frac{x^s}{s} {}_1F_1\left({s \atop s+1} \middle| -x\right), + + where ${}_1F_1$ is the (confluent) hypergeometric function. + + Examples + ======== + + >>> from sympy import lowergamma, S + >>> from sympy.abc import s, x + >>> lowergamma(s, x) + lowergamma(s, x) + >>> lowergamma(3, x) + -2*(x**2/2 + x + 1)*exp(-x) + 2 + >>> lowergamma(-S(1)/2, x) + -2*sqrt(pi)*erf(sqrt(x)) - 2*exp(-x)/sqrt(x) + + See Also + ======== + + gamma: Gamma function. + uppergamma: Upper incomplete gamma function. + polygamma: Polygamma function. + loggamma: Log Gamma function. + digamma: Digamma function. + trigamma: Trigamma function. + sympy.functions.special.beta_functions.beta: Euler Beta function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Incomplete_gamma_function#Lower_incomplete_gamma_function + .. [2] Abramowitz, Milton; Stegun, Irene A., eds. (1965), Chapter 6, + Section 5, Handbook of Mathematical Functions with Formulas, Graphs, + and Mathematical Tables + .. [3] https://dlmf.nist.gov/8 + .. [4] https://functions.wolfram.com/GammaBetaErf/Gamma2/ + .. [5] https://functions.wolfram.com/GammaBetaErf/Gamma3/ + + """ + + + def fdiff(self, argindex=2): + from sympy.functions.special.hyper import meijerg + if argindex == 2: + a, z = self.args + return exp(-unpolarify(z))*z**(a - 1) + elif argindex == 1: + a, z = self.args + return gamma(a)*digamma(a) - log(z)*uppergamma(a, z) \ + - meijerg([], [1, 1], [0, 0, a], [], z) + + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, a, x): + # For lack of a better place, we use this one to extract branching + # information. The following can be + # found in the literature (c/f references given above), albeit scattered: + # 1) For fixed x != 0, lowergamma(s, x) is an entire function of s + # 2) For fixed positive integers s, lowergamma(s, x) is an entire + # function of x. + # 3) For fixed non-positive integers s, + # lowergamma(s, exp(I*2*pi*n)*x) = + # 2*pi*I*n*(-1)**(-s)/factorial(-s) + lowergamma(s, x) + # (this follows from lowergamma(s, x).diff(x) = x**(s-1)*exp(-x)). + # 4) For fixed non-integral s, + # lowergamma(s, x) = x**s*gamma(s)*lowergamma_unbranched(s, x), + # where lowergamma_unbranched(s, x) is an entire function (in fact + # of both s and x), i.e. + # lowergamma(s, exp(2*I*pi*n)*x) = exp(2*pi*I*n*a)*lowergamma(a, x) + if x is S.Zero: + return S.Zero + nx, n = x.extract_branch_factor() + if a.is_integer and a.is_positive: + nx = unpolarify(x) + if nx != x: + return lowergamma(a, nx) + elif a.is_integer and a.is_nonpositive: + if n != 0: + return 2*pi*I*n*S.NegativeOne**(-a)/factorial(-a) + lowergamma(a, nx) + elif n != 0: + return exp(2*pi*I*n*a)*lowergamma(a, nx) + + # Special values. + if a.is_Number: + if a is S.One: + return S.One - exp(-x) + elif a is S.Half: + return sqrt(pi)*erf(sqrt(x)) + elif a.is_Integer or (2*a).is_Integer: + b = a - 1 + if b.is_positive: + if a.is_integer: + return factorial(b) - exp(-x) * factorial(b) * Add(*[x ** k / factorial(k) for k in range(a)]) + else: + return gamma(a)*(lowergamma(S.Half, x)/sqrt(pi) - exp(-x)*Add(*[x**(k - S.Half)/gamma(S.Half + k) for k in range(1, a + S.Half)])) + + if not a.is_Integer: + return S.NegativeOne**(S.Half - a)*pi*erf(sqrt(x))/gamma(1 - a) + exp(-x)*Add(*[x**(k + a - 1)*gamma(a)/gamma(a + k) for k in range(1, Rational(3, 2) - a)]) + + if x.is_zero: + return S.Zero + + def _eval_evalf(self, prec): + if all(x.is_number for x in self.args): + a = self.args[0]._to_mpmath(prec) + z = self.args[1]._to_mpmath(prec) + with workprec(prec): + res = mp.gammainc(a, 0, z) + return Expr._from_mpmath(res, prec) + else: + return self + + def _eval_conjugate(self): + x = self.args[1] + if x not in (S.Zero, S.NegativeInfinity): + return self.func(self.args[0].conjugate(), x.conjugate()) + + def _eval_is_meromorphic(self, x, a): + # By https://en.wikipedia.org/wiki/Incomplete_gamma_function#Holomorphic_extension, + # lowergamma(s, z) = z**s*gamma(s)*gammastar(s, z), + # where gammastar(s, z) is holomorphic for all s and z. + # Hence the singularities of lowergamma are z = 0 (branch + # point) and nonpositive integer values of s (poles of gamma(s)). + s, z = self.args + args_merom = fuzzy_and([z._eval_is_meromorphic(x, a), + s._eval_is_meromorphic(x, a)]) + if not args_merom: + return args_merom + z0 = z.subs(x, a) + if s.is_integer: + return fuzzy_and([s.is_positive, z0.is_finite]) + s0 = s.subs(x, a) + return fuzzy_and([s0.is_finite, z0.is_finite, fuzzy_not(z0.is_zero)]) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import O + s, z = self.args + if args0[0] is oo and not z.has(x): + coeff = z**s*exp(-z) + sum_expr = sum(z**k/rf(s, k + 1) for k in range(n - 1)) + o = O(z**s*s**(-n)) + return coeff*sum_expr + o + return super()._eval_aseries(n, args0, x, logx) + + def _eval_rewrite_as_uppergamma(self, s, x, **kwargs): + return gamma(s) - uppergamma(s, x) + + def _eval_rewrite_as_expint(self, s, x, **kwargs): + from sympy.functions.special.error_functions import expint + if s.is_integer and s.is_nonpositive: + return self + return self.rewrite(uppergamma).rewrite(expint) + + def _eval_is_zero(self): + x = self.args[1] + if x.is_zero: + return True + + +class uppergamma(DefinedFunction): + r""" + The upper incomplete gamma function. + + Explanation + =========== + + It can be defined as the meromorphic continuation of + + .. math:: + \Gamma(s, x) := \int_x^\infty t^{s-1} e^{-t} \mathrm{d}t = \Gamma(s) - \gamma(s, x). + + where $\gamma(s, x)$ is the lower incomplete gamma function, + :class:`lowergamma`. This can be shown to be the same as + + .. math:: + \Gamma(s, x) = \Gamma(s) - \frac{x^s}{s} {}_1F_1\left({s \atop s+1} \middle| -x\right), + + where ${}_1F_1$ is the (confluent) hypergeometric function. + + The upper incomplete gamma function is also essentially equivalent to the + generalized exponential integral: + + .. math:: + \operatorname{E}_{n}(x) = \int_{1}^{\infty}{\frac{e^{-xt}}{t^n} \, dt} = x^{n-1}\Gamma(1-n,x). + + Examples + ======== + + >>> from sympy import uppergamma, S + >>> from sympy.abc import s, x + >>> uppergamma(s, x) + uppergamma(s, x) + >>> uppergamma(3, x) + 2*(x**2/2 + x + 1)*exp(-x) + >>> uppergamma(-S(1)/2, x) + -2*sqrt(pi)*erfc(sqrt(x)) + 2*exp(-x)/sqrt(x) + >>> uppergamma(-2, x) + expint(3, x)/x**2 + + See Also + ======== + + gamma: Gamma function. + lowergamma: Lower incomplete gamma function. + polygamma: Polygamma function. + loggamma: Log Gamma function. + digamma: Digamma function. + trigamma: Trigamma function. + sympy.functions.special.beta_functions.beta: Euler Beta function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Incomplete_gamma_function#Upper_incomplete_gamma_function + .. [2] Abramowitz, Milton; Stegun, Irene A., eds. (1965), Chapter 6, + Section 5, Handbook of Mathematical Functions with Formulas, Graphs, + and Mathematical Tables + .. [3] https://dlmf.nist.gov/8 + .. [4] https://functions.wolfram.com/GammaBetaErf/Gamma2/ + .. [5] https://functions.wolfram.com/GammaBetaErf/Gamma3/ + .. [6] https://en.wikipedia.org/wiki/Exponential_integral#Relation_with_other_functions + + """ + + + def fdiff(self, argindex=2): + from sympy.functions.special.hyper import meijerg + if argindex == 2: + a, z = self.args + return -exp(-unpolarify(z))*z**(a - 1) + elif argindex == 1: + a, z = self.args + return uppergamma(a, z)*log(z) + meijerg([], [1, 1], [0, 0, a], [], z) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_evalf(self, prec): + if all(x.is_number for x in self.args): + a = self.args[0]._to_mpmath(prec) + z = self.args[1]._to_mpmath(prec) + with workprec(prec): + res = mp.gammainc(a, z, mp.inf) + return Expr._from_mpmath(res, prec) + return self + + @classmethod + def eval(cls, a, z): + from sympy.functions.special.error_functions import expint + if z.is_Number: + if z is S.NaN: + return S.NaN + elif z is oo: + return S.Zero + elif z.is_zero: + if re(a).is_positive: + return gamma(a) + + # We extract branching information here. C/f lowergamma. + nx, n = z.extract_branch_factor() + if a.is_integer and a.is_positive: + nx = unpolarify(z) + if z != nx: + return uppergamma(a, nx) + elif a.is_integer and a.is_nonpositive: + if n != 0: + return -2*pi*I*n*S.NegativeOne**(-a)/factorial(-a) + uppergamma(a, nx) + elif n != 0: + return gamma(a)*(1 - exp(2*pi*I*n*a)) + exp(2*pi*I*n*a)*uppergamma(a, nx) + + # Special values. + if a.is_Number: + if a is S.Zero and z.is_positive: + return -Ei(-z) + elif a is S.One: + return exp(-z) + elif a is S.Half: + return sqrt(pi)*erfc(sqrt(z)) + elif a.is_Integer or (2*a).is_Integer: + b = a - 1 + if b.is_positive: + if a.is_integer: + return exp(-z) * factorial(b) * Add(*[z**k / factorial(k) + for k in range(a)]) + else: + return (gamma(a) * erfc(sqrt(z)) + + S.NegativeOne**(a - S(3)/2) * exp(-z) * sqrt(z) + * Add(*[gamma(-S.Half - k) * (-z)**k / gamma(1-a) + for k in range(a - S.Half)])) + elif b.is_Integer: + return expint(-b, z)*unpolarify(z)**(b + 1) + + if not a.is_Integer: + return (S.NegativeOne**(S.Half - a) * pi*erfc(sqrt(z))/gamma(1-a) + - z**a * exp(-z) * Add(*[z**k * gamma(a) / gamma(a+k+1) + for k in range(S.Half - a)])) + + if a.is_zero and z.is_positive: + return -Ei(-z) + + if z.is_zero and re(a).is_positive: + return gamma(a) + + def _eval_conjugate(self): + z = self.args[1] + if z not in (S.Zero, S.NegativeInfinity): + return self.func(self.args[0].conjugate(), z.conjugate()) + + def _eval_is_meromorphic(self, x, a): + return lowergamma._eval_is_meromorphic(self, x, a) + + def _eval_rewrite_as_lowergamma(self, s, x, **kwargs): + return gamma(s) - lowergamma(s, x) + + def _eval_rewrite_as_tractable(self, s, x, **kwargs): + return exp(loggamma(s)) - lowergamma(s, x) + + def _eval_rewrite_as_expint(self, s, x, **kwargs): + from sympy.functions.special.error_functions import expint + return expint(1 - s, x)*x**s + + +############################################################################### +###################### POLYGAMMA and LOGGAMMA FUNCTIONS ####################### +############################################################################### + +class polygamma(DefinedFunction): + r""" + The function ``polygamma(n, z)`` returns ``log(gamma(z)).diff(n + 1)``. + + Explanation + =========== + + It is a meromorphic function on $\mathbb{C}$ and defined as the $(n+1)$-th + derivative of the logarithm of the gamma function: + + .. math:: + \psi^{(n)} (z) := \frac{\mathrm{d}^{n+1}}{\mathrm{d} z^{n+1}} \log\Gamma(z). + + For `n` not a nonnegative integer the generalization by Espinosa and Moll [5]_ + is used: + + .. math:: \psi(s,z) = \frac{\zeta'(s+1, z) + (\gamma + \psi(-s)) \zeta(s+1, z)} + {\Gamma(-s)} + + Examples + ======== + + Several special values are known: + + >>> from sympy import S, polygamma + >>> polygamma(0, 1) + -EulerGamma + >>> polygamma(0, 1/S(2)) + -2*log(2) - EulerGamma + >>> polygamma(0, 1/S(3)) + -log(3) - sqrt(3)*pi/6 - EulerGamma - log(sqrt(3)) + >>> polygamma(0, 1/S(4)) + -pi/2 - log(4) - log(2) - EulerGamma + >>> polygamma(0, 2) + 1 - EulerGamma + >>> polygamma(0, 23) + 19093197/5173168 - EulerGamma + + >>> from sympy import oo, I + >>> polygamma(0, oo) + oo + >>> polygamma(0, -oo) + oo + >>> polygamma(0, I*oo) + oo + >>> polygamma(0, -I*oo) + oo + + Differentiation with respect to $x$ is supported: + + >>> from sympy import Symbol, diff + >>> x = Symbol("x") + >>> diff(polygamma(0, x), x) + polygamma(1, x) + >>> diff(polygamma(0, x), x, 2) + polygamma(2, x) + >>> diff(polygamma(0, x), x, 3) + polygamma(3, x) + >>> diff(polygamma(1, x), x) + polygamma(2, x) + >>> diff(polygamma(1, x), x, 2) + polygamma(3, x) + >>> diff(polygamma(2, x), x) + polygamma(3, x) + >>> diff(polygamma(2, x), x, 2) + polygamma(4, x) + + >>> n = Symbol("n") + >>> diff(polygamma(n, x), x) + polygamma(n + 1, x) + >>> diff(polygamma(n, x), x, 2) + polygamma(n + 2, x) + + We can rewrite ``polygamma`` functions in terms of harmonic numbers: + + >>> from sympy import harmonic + >>> polygamma(0, x).rewrite(harmonic) + harmonic(x - 1) - EulerGamma + >>> polygamma(2, x).rewrite(harmonic) + 2*harmonic(x - 1, 3) - 2*zeta(3) + >>> ni = Symbol("n", integer=True) + >>> polygamma(ni, x).rewrite(harmonic) + (-1)**(n + 1)*(-harmonic(x - 1, n + 1) + zeta(n + 1))*factorial(n) + + See Also + ======== + + gamma: Gamma function. + lowergamma: Lower incomplete gamma function. + uppergamma: Upper incomplete gamma function. + loggamma: Log Gamma function. + digamma: Digamma function. + trigamma: Trigamma function. + sympy.functions.special.beta_functions.beta: Euler Beta function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Polygamma_function + .. [2] https://mathworld.wolfram.com/PolygammaFunction.html + .. [3] https://functions.wolfram.com/GammaBetaErf/PolyGamma/ + .. [4] https://functions.wolfram.com/GammaBetaErf/PolyGamma2/ + .. [5] O. Espinosa and V. Moll, "A generalized polygamma function", + *Integral Transforms and Special Functions* (2004), 101-115. + + """ + + @classmethod + def eval(cls, n, z): + if n is S.NaN or z is S.NaN: + return S.NaN + elif z is oo: + return oo if n.is_zero else S.Zero + elif z.is_Integer and z.is_nonpositive: + return S.ComplexInfinity + elif n is S.NegativeOne: + return loggamma(z) - log(2*pi) / 2 + elif n.is_zero: + if z is -oo or z.extract_multiplicatively(I) in (oo, -oo): + return oo + elif z.is_Integer: + return harmonic(z-1) - S.EulerGamma + elif z.is_Rational: + # TODO n == 1 also can do some rational z + p, q = z.as_numer_denom() + # only expand for small denominators to avoid creating long expressions + if q <= 6: + return expand_func(polygamma(S.Zero, z, evaluate=False)) + elif n.is_integer and n.is_nonnegative: + nz = unpolarify(z) + if z != nz: + return polygamma(n, nz) + if z.is_Integer: + return S.NegativeOne**(n+1) * factorial(n) * zeta(n+1, z) + elif z is S.Half: + return S.NegativeOne**(n+1) * factorial(n) * (2**(n+1)-1) * zeta(n+1) + + def _eval_is_real(self): + if self.args[0].is_positive and self.args[1].is_positive: + return True + + def _eval_is_complex(self): + z = self.args[1] + is_negative_integer = fuzzy_and([z.is_negative, z.is_integer]) + return fuzzy_and([z.is_complex, fuzzy_not(is_negative_integer)]) + + def _eval_is_positive(self): + n, z = self.args + if n.is_positive: + if n.is_odd and z.is_real: + return True + if n.is_even and z.is_positive: + return False + + def _eval_is_negative(self): + n, z = self.args + if n.is_positive: + if n.is_even and z.is_positive: + return True + if n.is_odd and z.is_real: + return False + + def _eval_expand_func(self, **hints): + n, z = self.args + + if n.is_Integer and n.is_nonnegative: + if z.is_Add: + coeff = z.args[0] + if coeff.is_Integer: + e = -(n + 1) + if coeff > 0: + tail = Add(*[Pow( + z - i, e) for i in range(1, int(coeff) + 1)]) + else: + tail = -Add(*[Pow( + z + i, e) for i in range(int(-coeff))]) + return polygamma(n, z - coeff) + S.NegativeOne**n*factorial(n)*tail + + elif z.is_Mul: + coeff, z = z.as_two_terms() + if coeff.is_Integer and coeff.is_positive: + tail = [polygamma(n, z + Rational( + i, coeff)) for i in range(int(coeff))] + if n == 0: + return Add(*tail)/coeff + log(coeff) + else: + return Add(*tail)/coeff**(n + 1) + z *= coeff + + if n == 0 and z.is_Rational: + p, q = z.as_numer_denom() + + # Reference: + # Values of the polygamma functions at rational arguments, J. Choi, 2007 + part_1 = -S.EulerGamma - pi * cot(p * pi / q) / 2 - log(q) + Add( + *[cos(2 * k * pi * p / q) * log(2 * sin(k * pi / q)) for k in range(1, q)]) + + if z > 0: + n = floor(z) + z0 = z - n + return part_1 + Add(*[1 / (z0 + k) for k in range(n)]) + elif z < 0: + n = floor(1 - z) + z0 = z + n + return part_1 - Add(*[1 / (z0 - 1 - k) for k in range(n)]) + + if n == -1: + return loggamma(z) - log(2*pi) / 2 + if n.is_integer is False or n.is_nonnegative is False: + s = Dummy("s") + dzt = zeta(s, z).diff(s).subs(s, n+1) + return (dzt + (S.EulerGamma + digamma(-n)) * zeta(n+1, z)) / gamma(-n) + + return polygamma(n, z) + + def _eval_rewrite_as_zeta(self, n, z, **kwargs): + if n.is_integer and n.is_positive: + return S.NegativeOne**(n + 1)*factorial(n)*zeta(n + 1, z) + + def _eval_rewrite_as_harmonic(self, n, z, **kwargs): + if n.is_integer: + if n.is_zero: + return harmonic(z - 1) - S.EulerGamma + else: + return S.NegativeOne**(n+1) * factorial(n) * (zeta(n+1) - harmonic(z-1, n+1)) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.series.order import Order + n, z = [a.as_leading_term(x) for a in self.args] + o = Order(z, x) + if n == 0 and o.contains(1/x): + logx = log(x) if logx is None else logx + return o.getn() * logx + else: + return self.func(n, z) + + def fdiff(self, argindex=2): + if argindex == 2: + n, z = self.args[:2] + return polygamma(n + 1, z) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + if args0[1] != oo or not \ + (self.args[0].is_Integer and self.args[0].is_nonnegative): + return super()._eval_aseries(n, args0, x, logx) + z = self.args[1] + N = self.args[0] + + if N == 0: + # digamma function series + # Abramowitz & Stegun, p. 259, 6.3.18 + r = log(z) - 1/(2*z) + o = None + if n < 2: + o = Order(1/z, x) + else: + m = ceiling((n + 1)//2) + l = [bernoulli(2*k) / (2*k*z**(2*k)) for k in range(1, m)] + r -= Add(*l) + o = Order(1/z**n, x) + return r._eval_nseries(x, n, logx) + o + else: + # proper polygamma function + # Abramowitz & Stegun, p. 260, 6.4.10 + # We return terms to order higher than O(x**n) on purpose + # -- otherwise we would not be able to return any terms for + # quite a long time! + fac = gamma(N) + e0 = fac + N*fac/(2*z) + m = ceiling((n + 1)//2) + for k in range(1, m): + fac = fac*(2*k + N - 1)*(2*k + N - 2) / ((2*k)*(2*k - 1)) + e0 += bernoulli(2*k)*fac/z**(2*k) + o = Order(1/z**(2*m), x) + if n == 0: + o = Order(1/z, x) + elif n == 1: + o = Order(1/z**2, x) + r = e0._eval_nseries(z, n, logx) + o + return (-1 * (-1/z)**N * r)._eval_nseries(x, n, logx) + + def _eval_evalf(self, prec): + if not all(i.is_number for i in self.args): + return + s = self.args[0]._to_mpmath(prec+12) + z = self.args[1]._to_mpmath(prec+12) + if mp.isint(z) and z <= 0: + return S.ComplexInfinity + with workprec(prec+12): + if mp.isint(s) and s >= 0: + res = mp.polygamma(s, z) + else: + zt = mp.zeta(s+1, z) + dzt = mp.zeta(s+1, z, 1) + res = (dzt + (mp.euler + mp.digamma(-s)) * zt) * mp.rgamma(-s) + return Expr._from_mpmath(res, prec) + + +class loggamma(DefinedFunction): + r""" + The ``loggamma`` function implements the logarithm of the + gamma function (i.e., $\log\Gamma(x)$). + + Examples + ======== + + Several special values are known. For numerical integral + arguments we have: + + >>> from sympy import loggamma + >>> loggamma(-2) + oo + >>> loggamma(0) + oo + >>> loggamma(1) + 0 + >>> loggamma(2) + 0 + >>> loggamma(3) + log(2) + + And for symbolic values: + + >>> from sympy import Symbol + >>> n = Symbol("n", integer=True, positive=True) + >>> loggamma(n) + log(gamma(n)) + >>> loggamma(-n) + oo + + For half-integral values: + + >>> from sympy import S + >>> loggamma(S(5)/2) + log(3*sqrt(pi)/4) + >>> loggamma(n/2) + log(2**(1 - n)*sqrt(pi)*gamma(n)/gamma(n/2 + 1/2)) + + And general rational arguments: + + >>> from sympy import expand_func + >>> L = loggamma(S(16)/3) + >>> expand_func(L).doit() + -5*log(3) + loggamma(1/3) + log(4) + log(7) + log(10) + log(13) + >>> L = loggamma(S(19)/4) + >>> expand_func(L).doit() + -4*log(4) + loggamma(3/4) + log(3) + log(7) + log(11) + log(15) + >>> L = loggamma(S(23)/7) + >>> expand_func(L).doit() + -3*log(7) + log(2) + loggamma(2/7) + log(9) + log(16) + + The ``loggamma`` function has the following limits towards infinity: + + >>> from sympy import oo + >>> loggamma(oo) + oo + >>> loggamma(-oo) + zoo + + The ``loggamma`` function obeys the mirror symmetry + if $x \in \mathbb{C} \setminus \{-\infty, 0\}$: + + >>> from sympy.abc import x + >>> from sympy import conjugate + >>> conjugate(loggamma(x)) + loggamma(conjugate(x)) + + Differentiation with respect to $x$ is supported: + + >>> from sympy import diff + >>> diff(loggamma(x), x) + polygamma(0, x) + + Series expansion is also supported: + + >>> from sympy import series + >>> series(loggamma(x), x, 0, 4).cancel() + -log(x) - EulerGamma*x + pi**2*x**2/12 - x**3*zeta(3)/3 + O(x**4) + + We can numerically evaluate the ``loggamma`` function + to arbitrary precision on the whole complex plane: + + >>> from sympy import I + >>> loggamma(5).evalf(30) + 3.17805383034794561964694160130 + >>> loggamma(I).evalf(20) + -0.65092319930185633889 - 1.8724366472624298171*I + + See Also + ======== + + gamma: Gamma function. + lowergamma: Lower incomplete gamma function. + uppergamma: Upper incomplete gamma function. + polygamma: Polygamma function. + digamma: Digamma function. + trigamma: Trigamma function. + sympy.functions.special.beta_functions.beta: Euler Beta function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gamma_function + .. [2] https://dlmf.nist.gov/5 + .. [3] https://mathworld.wolfram.com/LogGammaFunction.html + .. [4] https://functions.wolfram.com/GammaBetaErf/LogGamma/ + + """ + @classmethod + def eval(cls, z): + if z.is_integer: + if z.is_nonpositive: + return oo + elif z.is_positive: + return log(gamma(z)) + elif z.is_rational: + p, q = z.as_numer_denom() + # Half-integral values: + if p.is_positive and q == 2: + return log(sqrt(pi) * 2**(1 - p) * gamma(p) / gamma((p + 1)*S.Half)) + + if z is oo: + return oo + elif abs(z) is oo: + return S.ComplexInfinity + if z is S.NaN: + return S.NaN + + def _eval_expand_func(self, **hints): + from sympy.concrete.summations import Sum + z = self.args[0] + + if z.is_Rational: + p, q = z.as_numer_denom() + # General rational arguments (u + p/q) + # Split z as n + p/q with p < q + n = p // q + p = p - n*q + if p.is_positive and q.is_positive and p < q: + k = Dummy("k") + if n.is_positive: + return loggamma(p / q) - n*log(q) + Sum(log((k - 1)*q + p), (k, 1, n)) + elif n.is_negative: + return loggamma(p / q) - n*log(q) + pi*I*n - Sum(log(k*q - p), (k, 1, -n)) + elif n.is_zero: + return loggamma(p / q) + + return self + + def _eval_nseries(self, x, n, logx=None, cdir=0): + x0 = self.args[0].limit(x, 0) + if x0.is_zero: + f = self._eval_rewrite_as_intractable(*self.args) + return f._eval_nseries(x, n, logx) + return super()._eval_nseries(x, n, logx) + + def _eval_aseries(self, n, args0, x, logx): + from sympy.series.order import Order + if args0[0] != oo: + return super()._eval_aseries(n, args0, x, logx) + z = self.args[0] + r = log(z)*(z - S.Half) - z + log(2*pi)/2 + l = [bernoulli(2*k) / (2*k*(2*k - 1)*z**(2*k - 1)) for k in range(1, n)] + o = None + if n == 0: + o = Order(1, x) + else: + o = Order(1/z**n, x) + # It is very inefficient to first add the order and then do the nseries + return (r + Add(*l))._eval_nseries(x, n, logx) + o + + def _eval_rewrite_as_intractable(self, z, **kwargs): + return log(gamma(z)) + + def _eval_is_real(self): + z = self.args[0] + if z.is_positive: + return True + elif z.is_nonpositive: + return False + + def _eval_conjugate(self): + z = self.args[0] + if z not in (S.Zero, S.NegativeInfinity): + return self.func(z.conjugate()) + + def fdiff(self, argindex=1): + if argindex == 1: + return polygamma(0, self.args[0]) + else: + raise ArgumentIndexError(self, argindex) + + +class digamma(DefinedFunction): + r""" + The ``digamma`` function is the first derivative of the ``loggamma`` + function + + .. math:: + \psi(x) := \frac{\mathrm{d}}{\mathrm{d} z} \log\Gamma(z) + = \frac{\Gamma'(z)}{\Gamma(z) }. + + In this case, ``digamma(z) = polygamma(0, z)``. + + Examples + ======== + + >>> from sympy import digamma + >>> digamma(0) + zoo + >>> from sympy import Symbol + >>> z = Symbol('z') + >>> digamma(z) + polygamma(0, z) + + To retain ``digamma`` as it is: + + >>> digamma(0, evaluate=False) + digamma(0) + >>> digamma(z, evaluate=False) + digamma(z) + + See Also + ======== + + gamma: Gamma function. + lowergamma: Lower incomplete gamma function. + uppergamma: Upper incomplete gamma function. + polygamma: Polygamma function. + loggamma: Log Gamma function. + trigamma: Trigamma function. + sympy.functions.special.beta_functions.beta: Euler Beta function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Digamma_function + .. [2] https://mathworld.wolfram.com/DigammaFunction.html + .. [3] https://functions.wolfram.com/GammaBetaErf/PolyGamma2/ + + """ + def _eval_evalf(self, prec): + z = self.args[0] + nprec = prec_to_dps(prec) + return polygamma(0, z).evalf(n=nprec) + + def fdiff(self, argindex=1): + z = self.args[0] + return polygamma(0, z).fdiff() + + def _eval_is_real(self): + z = self.args[0] + return polygamma(0, z).is_real + + def _eval_is_positive(self): + z = self.args[0] + return polygamma(0, z).is_positive + + def _eval_is_negative(self): + z = self.args[0] + return polygamma(0, z).is_negative + + def _eval_aseries(self, n, args0, x, logx): + as_polygamma = self.rewrite(polygamma) + args0 = [S.Zero,] + args0 + return as_polygamma._eval_aseries(n, args0, x, logx) + + @classmethod + def eval(cls, z): + return polygamma(0, z) + + def _eval_expand_func(self, **hints): + z = self.args[0] + return polygamma(0, z).expand(func=True) + + def _eval_rewrite_as_harmonic(self, z, **kwargs): + return harmonic(z - 1) - S.EulerGamma + + def _eval_rewrite_as_polygamma(self, z, **kwargs): + return polygamma(0, z) + + def _eval_as_leading_term(self, x, logx, cdir): + z = self.args[0] + return polygamma(0, z).as_leading_term(x) + + + +class trigamma(DefinedFunction): + r""" + The ``trigamma`` function is the second derivative of the ``loggamma`` + function + + .. math:: + \psi^{(1)}(z) := \frac{\mathrm{d}^{2}}{\mathrm{d} z^{2}} \log\Gamma(z). + + In this case, ``trigamma(z) = polygamma(1, z)``. + + Examples + ======== + + >>> from sympy import trigamma + >>> trigamma(0) + zoo + >>> from sympy import Symbol + >>> z = Symbol('z') + >>> trigamma(z) + polygamma(1, z) + + To retain ``trigamma`` as it is: + + >>> trigamma(0, evaluate=False) + trigamma(0) + >>> trigamma(z, evaluate=False) + trigamma(z) + + + See Also + ======== + + gamma: Gamma function. + lowergamma: Lower incomplete gamma function. + uppergamma: Upper incomplete gamma function. + polygamma: Polygamma function. + loggamma: Log Gamma function. + digamma: Digamma function. + sympy.functions.special.beta_functions.beta: Euler Beta function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Trigamma_function + .. [2] https://mathworld.wolfram.com/TrigammaFunction.html + .. [3] https://functions.wolfram.com/GammaBetaErf/PolyGamma2/ + + """ + def _eval_evalf(self, prec): + z = self.args[0] + nprec = prec_to_dps(prec) + return polygamma(1, z).evalf(n=nprec) + + def fdiff(self, argindex=1): + z = self.args[0] + return polygamma(1, z).fdiff() + + def _eval_is_real(self): + z = self.args[0] + return polygamma(1, z).is_real + + def _eval_is_positive(self): + z = self.args[0] + return polygamma(1, z).is_positive + + def _eval_is_negative(self): + z = self.args[0] + return polygamma(1, z).is_negative + + def _eval_aseries(self, n, args0, x, logx): + as_polygamma = self.rewrite(polygamma) + args0 = [S.One,] + args0 + return as_polygamma._eval_aseries(n, args0, x, logx) + + @classmethod + def eval(cls, z): + return polygamma(1, z) + + def _eval_expand_func(self, **hints): + z = self.args[0] + return polygamma(1, z).expand(func=True) + + def _eval_rewrite_as_zeta(self, z, **kwargs): + return zeta(2, z) + + def _eval_rewrite_as_polygamma(self, z, **kwargs): + return polygamma(1, z) + + def _eval_rewrite_as_harmonic(self, z, **kwargs): + return -harmonic(z - 1, 2) + pi**2 / 6 + + def _eval_as_leading_term(self, x, logx, cdir): + z = self.args[0] + return polygamma(1, z).as_leading_term(x) + + +############################################################################### +##################### COMPLETE MULTIVARIATE GAMMA FUNCTION #################### +############################################################################### + + +class multigamma(DefinedFunction): + r""" + The multivariate gamma function is a generalization of the gamma function + + .. math:: + \Gamma_p(z) = \pi^{p(p-1)/4}\prod_{k=1}^p \Gamma[z + (1 - k)/2]. + + In a special case, ``multigamma(x, 1) = gamma(x)``. + + Examples + ======== + + >>> from sympy import S, multigamma + >>> from sympy import Symbol + >>> x = Symbol('x') + >>> p = Symbol('p', positive=True, integer=True) + + >>> multigamma(x, p) + pi**(p*(p - 1)/4)*Product(gamma(-_k/2 + x + 1/2), (_k, 1, p)) + + Several special values are known: + + >>> multigamma(1, 1) + 1 + >>> multigamma(4, 1) + 6 + >>> multigamma(S(3)/2, 1) + sqrt(pi)/2 + + Writing ``multigamma`` in terms of the ``gamma`` function: + + >>> multigamma(x, 1) + gamma(x) + + >>> multigamma(x, 2) + sqrt(pi)*gamma(x)*gamma(x - 1/2) + + >>> multigamma(x, 3) + pi**(3/2)*gamma(x)*gamma(x - 1)*gamma(x - 1/2) + + Parameters + ========== + + p : order or dimension of the multivariate gamma function + + See Also + ======== + + gamma, lowergamma, uppergamma, polygamma, loggamma, digamma, trigamma, + sympy.functions.special.beta_functions.beta + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Multivariate_gamma_function + + """ + unbranched = True + + def fdiff(self, argindex=2): + from sympy.concrete.summations import Sum + if argindex == 2: + x, p = self.args + k = Dummy("k") + return self.func(x, p)*Sum(polygamma(0, x + (1 - k)/2), (k, 1, p)) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, x, p): + from sympy.concrete.products import Product + if p.is_positive is False or p.is_integer is False: + raise ValueError('Order parameter p must be positive integer.') + k = Dummy("k") + return (pi**(p*(p - 1)/4)*Product(gamma(x + (1 - k)/2), + (k, 1, p))).doit() + + def _eval_conjugate(self): + x, p = self.args + return self.func(x.conjugate(), p) + + def _eval_is_real(self): + x, p = self.args + y = 2*x + if y.is_integer and (y <= (p - 1)) is True: + return False + if intlike(y) and (y <= (p - 1)): + return False + if y > (p - 1) or y.is_noninteger: + return True diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/hyper.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/hyper.py new file mode 100644 index 0000000000000000000000000000000000000000..3943e140821222a510c609a071b5dbbf08883745 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/hyper.py @@ -0,0 +1,1185 @@ +"""Hypergeometric and Meijer G-functions""" +from collections import Counter + +from sympy.core import S, Mod +from sympy.core.add import Add +from sympy.core.expr import Expr +from sympy.core.function import DefinedFunction, Derivative, ArgumentIndexError + +from sympy.core.containers import Tuple +from sympy.core.mul import Mul +from sympy.core.numbers import I, pi, oo, zoo +from sympy.core.parameters import global_parameters +from sympy.core.relational import Ne +from sympy.core.sorting import default_sort_key +from sympy.core.symbol import Dummy + +from sympy.external.gmpy import lcm +from sympy.functions import (sqrt, exp, log, sin, cos, asin, atan, + sinh, cosh, asinh, acosh, atanh, acoth) +from sympy.functions import factorial, RisingFactorial +from sympy.functions.elementary.complexes import Abs, re, unpolarify +from sympy.functions.elementary.exponential import exp_polar +from sympy.functions.elementary.integers import ceiling +from sympy.functions.elementary.piecewise import Piecewise +from sympy.logic.boolalg import (And, Or) +from sympy import ordered + + +class TupleArg(Tuple): + + # This method is only needed because hyper._eval_as_leading_term falls back + # (via super()) on using Function._eval_as_leading_term, which in turn + # calls as_leading_term on the args of the hyper. Ideally hyper should just + # have an _eval_as_leading_term method that handles all cases and this + # method should be removed because leading terms of tuples don't make + # sense. + def as_leading_term(self, *x, logx=None, cdir=0): + return TupleArg(*[f.as_leading_term(*x, logx=logx, cdir=cdir) for f in self.args]) + + def limit(self, x, xlim, dir='+'): + """ Compute limit x->xlim. + """ + from sympy.series.limits import limit + return TupleArg(*[limit(f, x, xlim, dir) for f in self.args]) + + +# TODO should __new__ accept **options? +# TODO should constructors should check if parameters are sensible? + + +def _prep_tuple(v): + """ + Turn an iterable argument *v* into a tuple and unpolarify, since both + hypergeometric and meijer g-functions are unbranched in their parameters. + + Examples + ======== + + >>> from sympy.functions.special.hyper import _prep_tuple + >>> _prep_tuple([1, 2, 3]) + (1, 2, 3) + >>> _prep_tuple((4, 5)) + (4, 5) + >>> _prep_tuple((7, 8, 9)) + (7, 8, 9) + + """ + return TupleArg(*[unpolarify(x) for x in v]) + + +class TupleParametersBase(DefinedFunction): + """ Base class that takes care of differentiation, when some of + the arguments are actually tuples. """ + # This is not deduced automatically since there are Tuples as arguments. + is_commutative = True + + def _eval_derivative(self, s): + try: + res = 0 + if self.args[0].has(s) or self.args[1].has(s): + for i, p in enumerate(self._diffargs): + m = self._diffargs[i].diff(s) + if m != 0: + res += self.fdiff((1, i))*m + return res + self.fdiff(3)*self.args[2].diff(s) + except (ArgumentIndexError, NotImplementedError): + return Derivative(self, s) + + +class hyper(TupleParametersBase): + r""" + The generalized hypergeometric function is defined by a series where + the ratios of successive terms are a rational function of the summation + index. When convergent, it is continued analytically to the largest + possible domain. + + Explanation + =========== + + The hypergeometric function depends on two vectors of parameters, called + the numerator parameters $a_p$, and the denominator parameters + $b_q$. It also has an argument $z$. The series definition is + + .. math :: + {}_pF_q\left(\begin{matrix} a_1, \cdots, a_p \\ b_1, \cdots, b_q \end{matrix} + \middle| z \right) + = \sum_{n=0}^\infty \frac{(a_1)_n \cdots (a_p)_n}{(b_1)_n \cdots (b_q)_n} + \frac{z^n}{n!}, + + where $(a)_n = (a)(a+1)\cdots(a+n-1)$ denotes the rising factorial. + + If one of the $b_q$ is a non-positive integer then the series is + undefined unless one of the $a_p$ is a larger (i.e., smaller in + magnitude) non-positive integer. If none of the $b_q$ is a + non-positive integer and one of the $a_p$ is a non-positive + integer, then the series reduces to a polynomial. To simplify the + following discussion, we assume that none of the $a_p$ or + $b_q$ is a non-positive integer. For more details, see the + references. + + The series converges for all $z$ if $p \le q$, and thus + defines an entire single-valued function in this case. If $p = + q+1$ the series converges for $|z| < 1$, and can be continued + analytically into a half-plane. If $p > q+1$ the series is + divergent for all $z$. + + Please note the hypergeometric function constructor currently does *not* + check if the parameters actually yield a well-defined function. + + Examples + ======== + + The parameters $a_p$ and $b_q$ can be passed as arbitrary + iterables, for example: + + >>> from sympy import hyper + >>> from sympy.abc import x, n, a + >>> h = hyper((1, 2, 3), [3, 4], x); h + hyper((1, 2), (4,), x) + >>> hyper((3, 1, 2), [3, 4], x, evaluate=False) # don't remove duplicates + hyper((1, 2, 3), (3, 4), x) + + There is also pretty printing (it looks better using Unicode): + + >>> from sympy import pprint + >>> pprint(h, use_unicode=False) + _ + |_ /1, 2 | \ + | | | x| + 2 1 \ 4 | / + + The parameters must always be iterables, even if they are vectors of + length one or zero: + + >>> hyper((1, ), [], x) + hyper((1,), (), x) + + But of course they may be variables (but if they depend on $x$ then you + should not expect much implemented functionality): + + >>> hyper((n, a), (n**2,), x) + hyper((a, n), (n**2,), x) + + The hypergeometric function generalizes many named special functions. + The function ``hyperexpand()`` tries to express a hypergeometric function + using named special functions. For example: + + >>> from sympy import hyperexpand + >>> hyperexpand(hyper([], [], x)) + exp(x) + + You can also use ``expand_func()``: + + >>> from sympy import expand_func + >>> expand_func(x*hyper([1, 1], [2], -x)) + log(x + 1) + + More examples: + + >>> from sympy import S + >>> hyperexpand(hyper([], [S(1)/2], -x**2/4)) + cos(x) + >>> hyperexpand(x*hyper([S(1)/2, S(1)/2], [S(3)/2], x**2)) + asin(x) + + We can also sometimes ``hyperexpand()`` parametric functions: + + >>> from sympy.abc import a + >>> hyperexpand(hyper([-a], [], x)) + (1 - x)**a + + See Also + ======== + + sympy.simplify.hyperexpand + gamma + meijerg + + References + ========== + + .. [1] Luke, Y. L. (1969), The Special Functions and Their Approximations, + Volume 1 + .. [2] https://en.wikipedia.org/wiki/Generalized_hypergeometric_function + + """ + + + def __new__(cls, ap, bq, z, **kwargs): + # TODO should we check convergence conditions? + if kwargs.pop('evaluate', global_parameters.evaluate): + ca = Counter(Tuple(*ap)) + cb = Counter(Tuple(*bq)) + common = ca & cb + arg = ap, bq = [], [] + for i, c in enumerate((ca, cb)): + c -= common + for k in ordered(c): + arg[i].extend([k]*c[k]) + else: + ap = list(ordered(ap)) + bq = list(ordered(bq)) + return super().__new__(cls, _prep_tuple(ap), _prep_tuple(bq), z, **kwargs) + + @classmethod + def eval(cls, ap, bq, z): + if len(ap) <= len(bq) or (len(ap) == len(bq) + 1 and (Abs(z) <= 1) == True): + nz = unpolarify(z) + if z != nz: + return hyper(ap, bq, nz) + + def fdiff(self, argindex=3): + if argindex != 3: + raise ArgumentIndexError(self, argindex) + nap = Tuple(*[a + 1 for a in self.ap]) + nbq = Tuple(*[b + 1 for b in self.bq]) + fac = Mul(*self.ap)/Mul(*self.bq) + return fac*hyper(nap, nbq, self.argument) + + def _eval_expand_func(self, **hints): + from sympy.functions.special.gamma_functions import gamma + from sympy.simplify.hyperexpand import hyperexpand + if len(self.ap) == 2 and len(self.bq) == 1 and self.argument == 1: + a, b = self.ap + c = self.bq[0] + return gamma(c)*gamma(c - a - b)/gamma(c - a)/gamma(c - b) + return hyperexpand(self) + + def _eval_rewrite_as_Sum(self, ap, bq, z, **kwargs): + from sympy.concrete.summations import Sum + n = Dummy("n", integer=True) + rfap = [RisingFactorial(a, n) for a in ap] + rfbq = [RisingFactorial(b, n) for b in bq] + coeff = Mul(*rfap) / Mul(*rfbq) + return Piecewise((Sum(coeff * z**n / factorial(n), (n, 0, oo)), + self.convergence_statement), (self, True)) + + def _eval_as_leading_term(self, x, logx, cdir): + arg = self.args[2] + x0 = arg.subs(x, 0) + if x0 is S.NaN: + x0 = arg.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + + if x0 is S.Zero: + return S.One + return super()._eval_as_leading_term(x, logx=logx, cdir=cdir) + + def _eval_nseries(self, x, n, logx, cdir=0): + + from sympy.series.order import Order + + arg = self.args[2] + x0 = arg.limit(x, 0) + ap = self.args[0] + bq = self.args[1] + + if not (arg == x and x0 == 0): + # It would be better to do something with arg.nseries here, rather + # than falling back on Function._eval_nseries. The code below + # though is not sufficient if arg is something like x/(x+1). + from sympy.simplify.hyperexpand import hyperexpand + return hyperexpand(super()._eval_nseries(x, n, logx)) + + terms = [] + + for i in range(n): + num = Mul(*[RisingFactorial(a, i) for a in ap]) + den = Mul(*[RisingFactorial(b, i) for b in bq]) + terms.append(((num/den) * (arg**i)) / factorial(i)) + + return (Add(*terms) + Order(x**n,x)) + + @property + def argument(self): + """ Argument of the hypergeometric function. """ + return self.args[2] + + @property + def ap(self): + """ Numerator parameters of the hypergeometric function. """ + return Tuple(*self.args[0]) + + @property + def bq(self): + """ Denominator parameters of the hypergeometric function. """ + return Tuple(*self.args[1]) + + @property + def _diffargs(self): + return self.ap + self.bq + + @property + def eta(self): + """ A quantity related to the convergence of the series. """ + return sum(self.ap) - sum(self.bq) + + @property + def radius_of_convergence(self): + """ + Compute the radius of convergence of the defining series. + + Explanation + =========== + + Note that even if this is not ``oo``, the function may still be + evaluated outside of the radius of convergence by analytic + continuation. But if this is zero, then the function is not actually + defined anywhere else. + + Examples + ======== + + >>> from sympy import hyper + >>> from sympy.abc import z + >>> hyper((1, 2), [3], z).radius_of_convergence + 1 + >>> hyper((1, 2, 3), [4], z).radius_of_convergence + 0 + >>> hyper((1, 2), (3, 4), z).radius_of_convergence + oo + + """ + if any(a.is_integer and (a <= 0) == True for a in self.ap + self.bq): + aints = [a for a in self.ap if a.is_Integer and (a <= 0) == True] + bints = [a for a in self.bq if a.is_Integer and (a <= 0) == True] + if len(aints) < len(bints): + return S.Zero + popped = False + for b in bints: + cancelled = False + while aints: + a = aints.pop() + if a >= b: + cancelled = True + break + popped = True + if not cancelled: + return S.Zero + if aints or popped: + # There are still non-positive numerator parameters. + # This is a polynomial. + return oo + if len(self.ap) == len(self.bq) + 1: + return S.One + elif len(self.ap) <= len(self.bq): + return oo + else: + return S.Zero + + @property + def convergence_statement(self): + """ Return a condition on z under which the series converges. """ + R = self.radius_of_convergence + if R == 0: + return False + if R == oo: + return True + # The special functions and their approximations, page 44 + e = self.eta + z = self.argument + c1 = And(re(e) < 0, abs(z) <= 1) + c2 = And(0 <= re(e), re(e) < 1, abs(z) <= 1, Ne(z, 1)) + c3 = And(re(e) >= 1, abs(z) < 1) + return Or(c1, c2, c3) + + def _eval_simplify(self, **kwargs): + from sympy.simplify.hyperexpand import hyperexpand + return hyperexpand(self) + + +class meijerg(TupleParametersBase): + r""" + The Meijer G-function is defined by a Mellin-Barnes type integral that + resembles an inverse Mellin transform. It generalizes the hypergeometric + functions. + + Explanation + =========== + + The Meijer G-function depends on four sets of parameters. There are + "*numerator parameters*" + $a_1, \ldots, a_n$ and $a_{n+1}, \ldots, a_p$, and there are + "*denominator parameters*" + $b_1, \ldots, b_m$ and $b_{m+1}, \ldots, b_q$. + Confusingly, it is traditionally denoted as follows (note the position + of $m$, $n$, $p$, $q$, and how they relate to the lengths of the four + parameter vectors): + + .. math :: + G_{p,q}^{m,n} \left(\begin{matrix}a_1, \cdots, a_n & a_{n+1}, \cdots, a_p \\ + b_1, \cdots, b_m & b_{m+1}, \cdots, b_q + \end{matrix} \middle| z \right). + + However, in SymPy the four parameter vectors are always available + separately (see examples), so that there is no need to keep track of the + decorating sub- and super-scripts on the G symbol. + + The G function is defined as the following integral: + + .. math :: + \frac{1}{2 \pi i} \int_L \frac{\prod_{j=1}^m \Gamma(b_j - s) + \prod_{j=1}^n \Gamma(1 - a_j + s)}{\prod_{j=m+1}^q \Gamma(1- b_j +s) + \prod_{j=n+1}^p \Gamma(a_j - s)} z^s \mathrm{d}s, + + where $\Gamma(z)$ is the gamma function. There are three possible + contours which we will not describe in detail here (see the references). + If the integral converges along more than one of them, the definitions + agree. The contours all separate the poles of $\Gamma(1-a_j+s)$ + from the poles of $\Gamma(b_k-s)$, so in particular the G function + is undefined if $a_j - b_k \in \mathbb{Z}_{>0}$ for some + $j \le n$ and $k \le m$. + + The conditions under which one of the contours yields a convergent integral + are complicated and we do not state them here, see the references. + + Please note currently the Meijer G-function constructor does *not* check any + convergence conditions. + + Examples + ======== + + You can pass the parameters either as four separate vectors: + + >>> from sympy import meijerg, Tuple, pprint + >>> from sympy.abc import x, a + >>> pprint(meijerg((1, 2), (a, 4), (5,), [], x), use_unicode=False) + __1, 2 /1, 2 4, a | \ + /__ | | x| + \_|4, 1 \ 5 | / + + Or as two nested vectors: + + >>> pprint(meijerg([(1, 2), (3, 4)], ([5], Tuple()), x), use_unicode=False) + __1, 2 /1, 2 3, 4 | \ + /__ | | x| + \_|4, 1 \ 5 | / + + As with the hypergeometric function, the parameters may be passed as + arbitrary iterables. Vectors of length zero and one also have to be + passed as iterables. The parameters need not be constants, but if they + depend on the argument then not much implemented functionality should be + expected. + + All the subvectors of parameters are available: + + >>> from sympy import pprint + >>> g = meijerg([1], [2], [3], [4], x) + >>> pprint(g, use_unicode=False) + __1, 1 /1 2 | \ + /__ | | x| + \_|2, 2 \3 4 | / + >>> g.an + (1,) + >>> g.ap + (1, 2) + >>> g.aother + (2,) + >>> g.bm + (3,) + >>> g.bq + (3, 4) + >>> g.bother + (4,) + + The Meijer G-function generalizes the hypergeometric functions. + In some cases it can be expressed in terms of hypergeometric functions, + using Slater's theorem. For example: + + >>> from sympy import hyperexpand + >>> from sympy.abc import a, b, c + >>> hyperexpand(meijerg([a], [], [c], [b], x), allow_hyper=True) + x**c*gamma(-a + c + 1)*hyper((-a + c + 1,), + (-b + c + 1,), -x)/gamma(-b + c + 1) + + Thus the Meijer G-function also subsumes many named functions as special + cases. You can use ``expand_func()`` or ``hyperexpand()`` to (try to) + rewrite a Meijer G-function in terms of named special functions. For + example: + + >>> from sympy import expand_func, S + >>> expand_func(meijerg([[],[]], [[0],[]], -x)) + exp(x) + >>> hyperexpand(meijerg([[],[]], [[S(1)/2],[0]], (x/2)**2)) + sin(x)/sqrt(pi) + + See Also + ======== + + hyper + sympy.simplify.hyperexpand + + References + ========== + + .. [1] Luke, Y. L. (1969), The Special Functions and Their Approximations, + Volume 1 + .. [2] https://en.wikipedia.org/wiki/Meijer_G-function + + """ + + + def __new__(cls, *args, **kwargs): + if len(args) == 5: + args = [(args[0], args[1]), (args[2], args[3]), args[4]] + if len(args) != 3: + raise TypeError("args must be either as, as', bs, bs', z or " + "as, bs, z") + + def tr(p): + if len(p) != 2: + raise TypeError("wrong argument") + p = [list(ordered(i)) for i in p] + return TupleArg(_prep_tuple(p[0]), _prep_tuple(p[1])) + + arg0, arg1 = tr(args[0]), tr(args[1]) + if Tuple(arg0, arg1).has(oo, zoo, -oo): + raise ValueError("G-function parameters must be finite") + if any((a - b).is_Integer and a - b > 0 + for a in arg0[0] for b in arg1[0]): + raise ValueError("no parameter a1, ..., an may differ from " + "any b1, ..., bm by a positive integer") + + # TODO should we check convergence conditions? + return super().__new__(cls, arg0, arg1, args[2], **kwargs) + + def fdiff(self, argindex=3): + if argindex != 3: + return self._diff_wrt_parameter(argindex[1]) + if len(self.an) >= 1: + a = list(self.an) + a[0] -= 1 + G = meijerg(a, self.aother, self.bm, self.bother, self.argument) + return 1/self.argument * ((self.an[0] - 1)*self + G) + elif len(self.bm) >= 1: + b = list(self.bm) + b[0] += 1 + G = meijerg(self.an, self.aother, b, self.bother, self.argument) + return 1/self.argument * (self.bm[0]*self - G) + else: + return S.Zero + + def _diff_wrt_parameter(self, idx): + # Differentiation wrt a parameter can only be done in very special + # cases. In particular, if we want to differentiate with respect to + # `a`, all other gamma factors have to reduce to rational functions. + # + # Let MT denote mellin transform. Suppose T(-s) is the gamma factor + # appearing in the definition of G. Then + # + # MT(log(z)G(z)) = d/ds T(s) = d/da T(s) + ... + # + # Thus d/da G(z) = log(z)G(z) - ... + # The ... can be evaluated as a G function under the above conditions, + # the formula being most easily derived by using + # + # d Gamma(s + n) Gamma(s + n) / 1 1 1 \ + # -- ------------ = ------------ | - + ---- + ... + --------- | + # ds Gamma(s) Gamma(s) \ s s + 1 s + n - 1 / + # + # which follows from the difference equation of the digamma function. + # (There is a similar equation for -n instead of +n). + + # We first figure out how to pair the parameters. + an = list(self.an) + ap = list(self.aother) + bm = list(self.bm) + bq = list(self.bother) + if idx < len(an): + an.pop(idx) + else: + idx -= len(an) + if idx < len(ap): + ap.pop(idx) + else: + idx -= len(ap) + if idx < len(bm): + bm.pop(idx) + else: + bq.pop(idx - len(bm)) + pairs1 = [] + pairs2 = [] + for l1, l2, pairs in [(an, bq, pairs1), (ap, bm, pairs2)]: + while l1: + x = l1.pop() + found = None + for i, y in enumerate(l2): + if not Mod((x - y).simplify(), 1): + found = i + break + if found is None: + raise NotImplementedError('Derivative not expressible ' + 'as G-function?') + y = l2[i] + l2.pop(i) + pairs.append((x, y)) + + # Now build the result. + res = log(self.argument)*self + + for a, b in pairs1: + sign = 1 + n = a - b + base = b + if n < 0: + sign = -1 + n = b - a + base = a + for k in range(n): + res -= sign*meijerg(self.an + (base + k + 1,), self.aother, + self.bm, self.bother + (base + k + 0,), + self.argument) + + for a, b in pairs2: + sign = 1 + n = b - a + base = a + if n < 0: + sign = -1 + n = a - b + base = b + for k in range(n): + res -= sign*meijerg(self.an, self.aother + (base + k + 1,), + self.bm + (base + k + 0,), self.bother, + self.argument) + + return res + + def get_period(self): + """ + Return a number $P$ such that $G(x*exp(I*P)) == G(x)$. + + Examples + ======== + + >>> from sympy import meijerg, pi, S + >>> from sympy.abc import z + + >>> meijerg([1], [], [], [], z).get_period() + 2*pi + >>> meijerg([pi], [], [], [], z).get_period() + oo + >>> meijerg([1, 2], [], [], [], z).get_period() + oo + >>> meijerg([1,1], [2], [1, S(1)/2, S(1)/3], [1], z).get_period() + 12*pi + + """ + # This follows from slater's theorem. + def compute(l): + # first check that no two differ by an integer + for i, b in enumerate(l): + if not b.is_Rational: + return oo + for j in range(i + 1, len(l)): + if not Mod((b - l[j]).simplify(), 1): + return oo + return lcm(*(x.q for x in l)) + beta = compute(self.bm) + alpha = compute(self.an) + p, q = len(self.ap), len(self.bq) + if p == q: + if oo in (alpha, beta): + return oo + return 2*pi*lcm(alpha, beta) + elif p < q: + return 2*pi*beta + else: + return 2*pi*alpha + + def _eval_expand_func(self, **hints): + from sympy.simplify.hyperexpand import hyperexpand + return hyperexpand(self) + + def _eval_evalf(self, prec): + # The default code is insufficient for polar arguments. + # mpmath provides an optional argument "r", which evaluates + # G(z**(1/r)). I am not sure what its intended use is, but we hijack it + # here in the following way: to evaluate at a number z of |argument| + # less than (say) n*pi, we put r=1/n, compute z' = root(z, n) + # (carefully so as not to loose the branch information), and evaluate + # G(z'**(1/r)) = G(z'**n) = G(z). + import mpmath + znum = self.argument._eval_evalf(prec) + if znum.has(exp_polar): + znum, branch = znum.as_coeff_mul(exp_polar) + if len(branch) != 1: + return + branch = branch[0].args[0]/I + else: + branch = S.Zero + n = ceiling(abs(branch/pi)) + 1 + znum = znum**(S.One/n)*exp(I*branch / n) + + # Convert all args to mpf or mpc + try: + [z, r, ap, bq] = [arg._to_mpmath(prec) + for arg in [znum, 1/n, self.args[0], self.args[1]]] + except ValueError: + return + + with mpmath.workprec(prec): + v = mpmath.meijerg(ap, bq, z, r) + + return Expr._from_mpmath(v, prec) + + def _eval_as_leading_term(self, x, logx, cdir): + from sympy.simplify.hyperexpand import hyperexpand + return hyperexpand(self).as_leading_term(x, logx=logx, cdir=cdir) + + def integrand(self, s): + """ Get the defining integrand D(s). """ + from sympy.functions.special.gamma_functions import gamma + return self.argument**s \ + * Mul(*(gamma(b - s) for b in self.bm)) \ + * Mul(*(gamma(1 - a + s) for a in self.an)) \ + / Mul(*(gamma(1 - b + s) for b in self.bother)) \ + / Mul(*(gamma(a - s) for a in self.aother)) + + @property + def argument(self): + """ Argument of the Meijer G-function. """ + return self.args[2] + + @property + def an(self): + """ First set of numerator parameters. """ + return Tuple(*self.args[0][0]) + + @property + def ap(self): + """ Combined numerator parameters. """ + return Tuple(*(self.args[0][0] + self.args[0][1])) + + @property + def aother(self): + """ Second set of numerator parameters. """ + return Tuple(*self.args[0][1]) + + @property + def bm(self): + """ First set of denominator parameters. """ + return Tuple(*self.args[1][0]) + + @property + def bq(self): + """ Combined denominator parameters. """ + return Tuple(*(self.args[1][0] + self.args[1][1])) + + @property + def bother(self): + """ Second set of denominator parameters. """ + return Tuple(*self.args[1][1]) + + @property + def _diffargs(self): + return self.ap + self.bq + + @property + def nu(self): + """ A quantity related to the convergence region of the integral, + c.f. references. """ + return sum(self.bq) - sum(self.ap) + + @property + def delta(self): + """ A quantity related to the convergence region of the integral, + c.f. references. """ + return len(self.bm) + len(self.an) - S(len(self.ap) + len(self.bq))/2 + + @property + def is_number(self): + """ Returns true if expression has numeric data only. """ + return not self.free_symbols + + +class HyperRep(DefinedFunction): + """ + A base class for "hyper representation functions". + + This is used exclusively in ``hyperexpand()``, but fits more logically here. + + pFq is branched at 1 if p == q+1. For use with slater-expansion, we want + define an "analytic continuation" to all polar numbers, which is + continuous on circles and on the ray t*exp_polar(I*pi). Moreover, we want + a "nice" expression for the various cases. + + This base class contains the core logic, concrete derived classes only + supply the actual functions. + + """ + + + @classmethod + def eval(cls, *args): + newargs = tuple(map(unpolarify, args[:-1])) + args[-1:] + if args != newargs: + return cls(*newargs) + + @classmethod + def _expr_small(cls, x): + """ An expression for F(x) which holds for |x| < 1. """ + raise NotImplementedError + + @classmethod + def _expr_small_minus(cls, x): + """ An expression for F(-x) which holds for |x| < 1. """ + raise NotImplementedError + + @classmethod + def _expr_big(cls, x, n): + """ An expression for F(exp_polar(2*I*pi*n)*x), |x| > 1. """ + raise NotImplementedError + + @classmethod + def _expr_big_minus(cls, x, n): + """ An expression for F(exp_polar(2*I*pi*n + pi*I)*x), |x| > 1. """ + raise NotImplementedError + + def _eval_rewrite_as_nonrep(self, *args, **kwargs): + x, n = self.args[-1].extract_branch_factor(allow_half=True) + minus = False + newargs = self.args[:-1] + (x,) + if not n.is_Integer: + minus = True + n -= S.Half + newerargs = newargs + (n,) + if minus: + small = self._expr_small_minus(*newargs) + big = self._expr_big_minus(*newerargs) + else: + small = self._expr_small(*newargs) + big = self._expr_big(*newerargs) + + if big == small: + return small + return Piecewise((big, abs(x) > 1), (small, True)) + + def _eval_rewrite_as_nonrepsmall(self, *args, **kwargs): + x, n = self.args[-1].extract_branch_factor(allow_half=True) + args = self.args[:-1] + (x,) + if not n.is_Integer: + return self._expr_small_minus(*args) + return self._expr_small(*args) + + +class HyperRep_power1(HyperRep): + """ Return a representative for hyper([-a], [], z) == (1 - z)**a. """ + + @classmethod + def _expr_small(cls, a, x): + return (1 - x)**a + + @classmethod + def _expr_small_minus(cls, a, x): + return (1 + x)**a + + @classmethod + def _expr_big(cls, a, x, n): + if a.is_integer: + return cls._expr_small(a, x) + return (x - 1)**a*exp((2*n - 1)*pi*I*a) + + @classmethod + def _expr_big_minus(cls, a, x, n): + if a.is_integer: + return cls._expr_small_minus(a, x) + return (1 + x)**a*exp(2*n*pi*I*a) + + +class HyperRep_power2(HyperRep): + """ Return a representative for hyper([a, a - 1/2], [2*a], z). """ + + @classmethod + def _expr_small(cls, a, x): + return 2**(2*a - 1)*(1 + sqrt(1 - x))**(1 - 2*a) + + @classmethod + def _expr_small_minus(cls, a, x): + return 2**(2*a - 1)*(1 + sqrt(1 + x))**(1 - 2*a) + + @classmethod + def _expr_big(cls, a, x, n): + sgn = -1 + if n.is_odd: + sgn = 1 + n -= 1 + return 2**(2*a - 1)*(1 + sgn*I*sqrt(x - 1))**(1 - 2*a) \ + *exp(-2*n*pi*I*a) + + @classmethod + def _expr_big_minus(cls, a, x, n): + sgn = 1 + if n.is_odd: + sgn = -1 + return sgn*2**(2*a - 1)*(sqrt(1 + x) + sgn)**(1 - 2*a)*exp(-2*pi*I*a*n) + + +class HyperRep_log1(HyperRep): + """ Represent -z*hyper([1, 1], [2], z) == log(1 - z). """ + @classmethod + def _expr_small(cls, x): + return log(1 - x) + + @classmethod + def _expr_small_minus(cls, x): + return log(1 + x) + + @classmethod + def _expr_big(cls, x, n): + return log(x - 1) + (2*n - 1)*pi*I + + @classmethod + def _expr_big_minus(cls, x, n): + return log(1 + x) + 2*n*pi*I + + +class HyperRep_atanh(HyperRep): + """ Represent hyper([1/2, 1], [3/2], z) == atanh(sqrt(z))/sqrt(z). """ + @classmethod + def _expr_small(cls, x): + return atanh(sqrt(x))/sqrt(x) + + def _expr_small_minus(cls, x): + return atan(sqrt(x))/sqrt(x) + + def _expr_big(cls, x, n): + if n.is_even: + return (acoth(sqrt(x)) + I*pi/2)/sqrt(x) + else: + return (acoth(sqrt(x)) - I*pi/2)/sqrt(x) + + def _expr_big_minus(cls, x, n): + if n.is_even: + return atan(sqrt(x))/sqrt(x) + else: + return (atan(sqrt(x)) - pi)/sqrt(x) + + +class HyperRep_asin1(HyperRep): + """ Represent hyper([1/2, 1/2], [3/2], z) == asin(sqrt(z))/sqrt(z). """ + @classmethod + def _expr_small(cls, z): + return asin(sqrt(z))/sqrt(z) + + @classmethod + def _expr_small_minus(cls, z): + return asinh(sqrt(z))/sqrt(z) + + @classmethod + def _expr_big(cls, z, n): + return S.NegativeOne**n*((S.Half - n)*pi/sqrt(z) + I*acosh(sqrt(z))/sqrt(z)) + + @classmethod + def _expr_big_minus(cls, z, n): + return S.NegativeOne**n*(asinh(sqrt(z))/sqrt(z) + n*pi*I/sqrt(z)) + + +class HyperRep_asin2(HyperRep): + """ Represent hyper([1, 1], [3/2], z) == asin(sqrt(z))/sqrt(z)/sqrt(1-z). """ + # TODO this can be nicer + @classmethod + def _expr_small(cls, z): + return HyperRep_asin1._expr_small(z) \ + /HyperRep_power1._expr_small(S.Half, z) + + @classmethod + def _expr_small_minus(cls, z): + return HyperRep_asin1._expr_small_minus(z) \ + /HyperRep_power1._expr_small_minus(S.Half, z) + + @classmethod + def _expr_big(cls, z, n): + return HyperRep_asin1._expr_big(z, n) \ + /HyperRep_power1._expr_big(S.Half, z, n) + + @classmethod + def _expr_big_minus(cls, z, n): + return HyperRep_asin1._expr_big_minus(z, n) \ + /HyperRep_power1._expr_big_minus(S.Half, z, n) + + +class HyperRep_sqrts1(HyperRep): + """ Return a representative for hyper([-a, 1/2 - a], [1/2], z). """ + + @classmethod + def _expr_small(cls, a, z): + return ((1 - sqrt(z))**(2*a) + (1 + sqrt(z))**(2*a))/2 + + @classmethod + def _expr_small_minus(cls, a, z): + return (1 + z)**a*cos(2*a*atan(sqrt(z))) + + @classmethod + def _expr_big(cls, a, z, n): + if n.is_even: + return ((sqrt(z) + 1)**(2*a)*exp(2*pi*I*n*a) + + (sqrt(z) - 1)**(2*a)*exp(2*pi*I*(n - 1)*a))/2 + else: + n -= 1 + return ((sqrt(z) - 1)**(2*a)*exp(2*pi*I*a*(n + 1)) + + (sqrt(z) + 1)**(2*a)*exp(2*pi*I*a*n))/2 + + @classmethod + def _expr_big_minus(cls, a, z, n): + if n.is_even: + return (1 + z)**a*exp(2*pi*I*n*a)*cos(2*a*atan(sqrt(z))) + else: + return (1 + z)**a*exp(2*pi*I*n*a)*cos(2*a*atan(sqrt(z)) - 2*pi*a) + + +class HyperRep_sqrts2(HyperRep): + """ Return a representative for + sqrt(z)/2*[(1-sqrt(z))**2a - (1 + sqrt(z))**2a] + == -2*z/(2*a+1) d/dz hyper([-a - 1/2, -a], [1/2], z)""" + + @classmethod + def _expr_small(cls, a, z): + return sqrt(z)*((1 - sqrt(z))**(2*a) - (1 + sqrt(z))**(2*a))/2 + + @classmethod + def _expr_small_minus(cls, a, z): + return sqrt(z)*(1 + z)**a*sin(2*a*atan(sqrt(z))) + + @classmethod + def _expr_big(cls, a, z, n): + if n.is_even: + return sqrt(z)/2*((sqrt(z) - 1)**(2*a)*exp(2*pi*I*a*(n - 1)) - + (sqrt(z) + 1)**(2*a)*exp(2*pi*I*a*n)) + else: + n -= 1 + return sqrt(z)/2*((sqrt(z) - 1)**(2*a)*exp(2*pi*I*a*(n + 1)) - + (sqrt(z) + 1)**(2*a)*exp(2*pi*I*a*n)) + + def _expr_big_minus(cls, a, z, n): + if n.is_even: + return (1 + z)**a*exp(2*pi*I*n*a)*sqrt(z)*sin(2*a*atan(sqrt(z))) + else: + return (1 + z)**a*exp(2*pi*I*n*a)*sqrt(z) \ + *sin(2*a*atan(sqrt(z)) - 2*pi*a) + + +class HyperRep_log2(HyperRep): + """ Represent log(1/2 + sqrt(1 - z)/2) == -z/4*hyper([3/2, 1, 1], [2, 2], z) """ + + @classmethod + def _expr_small(cls, z): + return log(S.Half + sqrt(1 - z)/2) + + @classmethod + def _expr_small_minus(cls, z): + return log(S.Half + sqrt(1 + z)/2) + + @classmethod + def _expr_big(cls, z, n): + if n.is_even: + return (n - S.Half)*pi*I + log(sqrt(z)/2) + I*asin(1/sqrt(z)) + else: + return (n - S.Half)*pi*I + log(sqrt(z)/2) - I*asin(1/sqrt(z)) + + def _expr_big_minus(cls, z, n): + if n.is_even: + return pi*I*n + log(S.Half + sqrt(1 + z)/2) + else: + return pi*I*n + log(sqrt(1 + z)/2 - S.Half) + + +class HyperRep_cosasin(HyperRep): + """ Represent hyper([a, -a], [1/2], z) == cos(2*a*asin(sqrt(z))). """ + # Note there are many alternative expressions, e.g. as powers of a sum of + # square roots. + + @classmethod + def _expr_small(cls, a, z): + return cos(2*a*asin(sqrt(z))) + + @classmethod + def _expr_small_minus(cls, a, z): + return cosh(2*a*asinh(sqrt(z))) + + @classmethod + def _expr_big(cls, a, z, n): + return cosh(2*a*acosh(sqrt(z)) + a*pi*I*(2*n - 1)) + + @classmethod + def _expr_big_minus(cls, a, z, n): + return cosh(2*a*asinh(sqrt(z)) + 2*a*pi*I*n) + + +class HyperRep_sinasin(HyperRep): + """ Represent 2*a*z*hyper([1 - a, 1 + a], [3/2], z) + == sqrt(z)/sqrt(1-z)*sin(2*a*asin(sqrt(z))) """ + + @classmethod + def _expr_small(cls, a, z): + return sqrt(z)/sqrt(1 - z)*sin(2*a*asin(sqrt(z))) + + @classmethod + def _expr_small_minus(cls, a, z): + return -sqrt(z)/sqrt(1 + z)*sinh(2*a*asinh(sqrt(z))) + + @classmethod + def _expr_big(cls, a, z, n): + return -1/sqrt(1 - 1/z)*sinh(2*a*acosh(sqrt(z)) + a*pi*I*(2*n - 1)) + + @classmethod + def _expr_big_minus(cls, a, z, n): + return -1/sqrt(1 + 1/z)*sinh(2*a*asinh(sqrt(z)) + 2*a*pi*I*n) + +class appellf1(DefinedFunction): + r""" + This is the Appell hypergeometric function of two variables as: + + .. math :: + F_1(a,b_1,b_2,c,x,y) = \sum_{m=0}^{\infty} \sum_{n=0}^{\infty} + \frac{(a)_{m+n} (b_1)_m (b_2)_n}{(c)_{m+n}} + \frac{x^m y^n}{m! n!}. + + Examples + ======== + + >>> from sympy import appellf1, symbols + >>> x, y, a, b1, b2, c = symbols('x y a b1 b2 c') + >>> appellf1(2., 1., 6., 4., 5., 6.) + 0.0063339426292673 + >>> appellf1(12., 12., 6., 4., 0.5, 0.12) + 172870711.659936 + >>> appellf1(40, 2, 6, 4, 15, 60) + appellf1(40, 2, 6, 4, 15, 60) + >>> appellf1(20., 12., 10., 3., 0.5, 0.12) + 15605338197184.4 + >>> appellf1(40, 2, 6, 4, x, y) + appellf1(40, 2, 6, 4, x, y) + >>> appellf1(a, b1, b2, c, x, y) + appellf1(a, b1, b2, c, x, y) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Appell_series + .. [2] https://functions.wolfram.com/HypergeometricFunctions/AppellF1/ + + """ + + @classmethod + def eval(cls, a, b1, b2, c, x, y): + if default_sort_key(b1) > default_sort_key(b2): + b1, b2 = b2, b1 + x, y = y, x + return cls(a, b1, b2, c, x, y) + elif b1 == b2 and default_sort_key(x) > default_sort_key(y): + x, y = y, x + return cls(a, b1, b2, c, x, y) + if x == 0 and y == 0: + return S.One + + def fdiff(self, argindex=5): + a, b1, b2, c, x, y = self.args + if argindex == 5: + return (a*b1/c)*appellf1(a + 1, b1 + 1, b2, c + 1, x, y) + elif argindex == 6: + return (a*b2/c)*appellf1(a + 1, b1, b2 + 1, c + 1, x, y) + elif argindex in (1, 2, 3, 4): + return Derivative(self, self.args[argindex-1]) + else: + raise ArgumentIndexError(self, argindex) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/mathieu_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/mathieu_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..66bccd8d3e6dd357e1e0b93fb5cb5ad4c5f1367f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/mathieu_functions.py @@ -0,0 +1,269 @@ +""" This module contains the Mathieu functions. +""" + +from sympy.core.function import DefinedFunction, ArgumentIndexError +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import sin, cos + + +class MathieuBase(DefinedFunction): + """ + Abstract base class for Mathieu functions. + + This class is meant to reduce code duplication. + + """ + + unbranched = True + + def _eval_conjugate(self): + a, q, z = self.args + return self.func(a.conjugate(), q.conjugate(), z.conjugate()) + + +class mathieus(MathieuBase): + r""" + The Mathieu Sine function $S(a,q,z)$. + + Explanation + =========== + + This function is one solution of the Mathieu differential equation: + + .. math :: + y(x)^{\prime\prime} + (a - 2 q \cos(2 x)) y(x) = 0 + + The other solution is the Mathieu Cosine function. + + Examples + ======== + + >>> from sympy import diff, mathieus + >>> from sympy.abc import a, q, z + + >>> mathieus(a, q, z) + mathieus(a, q, z) + + >>> mathieus(a, 0, z) + sin(sqrt(a)*z) + + >>> diff(mathieus(a, q, z), z) + mathieusprime(a, q, z) + + See Also + ======== + + mathieuc: Mathieu cosine function. + mathieusprime: Derivative of Mathieu sine function. + mathieucprime: Derivative of Mathieu cosine function. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Mathieu_function + .. [2] https://dlmf.nist.gov/28 + .. [3] https://mathworld.wolfram.com/MathieuFunction.html + .. [4] https://functions.wolfram.com/MathieuandSpheroidalFunctions/MathieuS/ + + """ + + def fdiff(self, argindex=1): + if argindex == 3: + a, q, z = self.args + return mathieusprime(a, q, z) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, a, q, z): + if q.is_Number and q.is_zero: + return sin(sqrt(a)*z) + # Try to pull out factors of -1 + if z.could_extract_minus_sign(): + return -cls(a, q, -z) + + +class mathieuc(MathieuBase): + r""" + The Mathieu Cosine function $C(a,q,z)$. + + Explanation + =========== + + This function is one solution of the Mathieu differential equation: + + .. math :: + y(x)^{\prime\prime} + (a - 2 q \cos(2 x)) y(x) = 0 + + The other solution is the Mathieu Sine function. + + Examples + ======== + + >>> from sympy import diff, mathieuc + >>> from sympy.abc import a, q, z + + >>> mathieuc(a, q, z) + mathieuc(a, q, z) + + >>> mathieuc(a, 0, z) + cos(sqrt(a)*z) + + >>> diff(mathieuc(a, q, z), z) + mathieucprime(a, q, z) + + See Also + ======== + + mathieus: Mathieu sine function + mathieusprime: Derivative of Mathieu sine function + mathieucprime: Derivative of Mathieu cosine function + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Mathieu_function + .. [2] https://dlmf.nist.gov/28 + .. [3] https://mathworld.wolfram.com/MathieuFunction.html + .. [4] https://functions.wolfram.com/MathieuandSpheroidalFunctions/MathieuC/ + + """ + + def fdiff(self, argindex=1): + if argindex == 3: + a, q, z = self.args + return mathieucprime(a, q, z) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, a, q, z): + if q.is_Number and q.is_zero: + return cos(sqrt(a)*z) + # Try to pull out factors of -1 + if z.could_extract_minus_sign(): + return cls(a, q, -z) + + +class mathieusprime(MathieuBase): + r""" + The derivative $S^{\prime}(a,q,z)$ of the Mathieu Sine function. + + Explanation + =========== + + This function is one solution of the Mathieu differential equation: + + .. math :: + y(x)^{\prime\prime} + (a - 2 q \cos(2 x)) y(x) = 0 + + The other solution is the Mathieu Cosine function. + + Examples + ======== + + >>> from sympy import diff, mathieusprime + >>> from sympy.abc import a, q, z + + >>> mathieusprime(a, q, z) + mathieusprime(a, q, z) + + >>> mathieusprime(a, 0, z) + sqrt(a)*cos(sqrt(a)*z) + + >>> diff(mathieusprime(a, q, z), z) + (-a + 2*q*cos(2*z))*mathieus(a, q, z) + + See Also + ======== + + mathieus: Mathieu sine function + mathieuc: Mathieu cosine function + mathieucprime: Derivative of Mathieu cosine function + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Mathieu_function + .. [2] https://dlmf.nist.gov/28 + .. [3] https://mathworld.wolfram.com/MathieuFunction.html + .. [4] https://functions.wolfram.com/MathieuandSpheroidalFunctions/MathieuSPrime/ + + """ + + def fdiff(self, argindex=1): + if argindex == 3: + a, q, z = self.args + return (2*q*cos(2*z) - a)*mathieus(a, q, z) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, a, q, z): + if q.is_Number and q.is_zero: + return sqrt(a)*cos(sqrt(a)*z) + # Try to pull out factors of -1 + if z.could_extract_minus_sign(): + return cls(a, q, -z) + + +class mathieucprime(MathieuBase): + r""" + The derivative $C^{\prime}(a,q,z)$ of the Mathieu Cosine function. + + Explanation + =========== + + This function is one solution of the Mathieu differential equation: + + .. math :: + y(x)^{\prime\prime} + (a - 2 q \cos(2 x)) y(x) = 0 + + The other solution is the Mathieu Sine function. + + Examples + ======== + + >>> from sympy import diff, mathieucprime + >>> from sympy.abc import a, q, z + + >>> mathieucprime(a, q, z) + mathieucprime(a, q, z) + + >>> mathieucprime(a, 0, z) + -sqrt(a)*sin(sqrt(a)*z) + + >>> diff(mathieucprime(a, q, z), z) + (-a + 2*q*cos(2*z))*mathieuc(a, q, z) + + See Also + ======== + + mathieus: Mathieu sine function + mathieuc: Mathieu cosine function + mathieusprime: Derivative of Mathieu sine function + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Mathieu_function + .. [2] https://dlmf.nist.gov/28 + .. [3] https://mathworld.wolfram.com/MathieuFunction.html + .. [4] https://functions.wolfram.com/MathieuandSpheroidalFunctions/MathieuCPrime/ + + """ + + def fdiff(self, argindex=1): + if argindex == 3: + a, q, z = self.args + return (2*q*cos(2*z) - a)*mathieuc(a, q, z) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, a, q, z): + if q.is_Number and q.is_zero: + return -sqrt(a)*sin(sqrt(a)*z) + # Try to pull out factors of -1 + if z.could_extract_minus_sign(): + return -cls(a, q, -z) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/polynomials.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/polynomials.py new file mode 100644 index 0000000000000000000000000000000000000000..5816baef600baf957c31a9dddaa5571da86d754a --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/polynomials.py @@ -0,0 +1,1447 @@ +""" +This module mainly implements special orthogonal polynomials. + +See also functions.combinatorial.numbers which contains some +combinatorial polynomials. + +""" + +from sympy.core import Rational +from sympy.core.function import DefinedFunction, ArgumentIndexError +from sympy.core.singleton import S +from sympy.core.symbol import Dummy +from sympy.functions.combinatorial.factorials import binomial, factorial, RisingFactorial +from sympy.functions.elementary.complexes import re +from sympy.functions.elementary.exponential import exp +from sympy.functions.elementary.integers import floor +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import cos, sec +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import hyper +from sympy.polys.orthopolys import (chebyshevt_poly, chebyshevu_poly, + gegenbauer_poly, hermite_poly, hermite_prob_poly, + jacobi_poly, laguerre_poly, legendre_poly) + +_x = Dummy('x') + + +class OrthogonalPolynomial(DefinedFunction): + """Base class for orthogonal polynomials. + """ + + @classmethod + def _eval_at_order(cls, n, x): + if n.is_integer and n >= 0: + return cls._ortho_poly(int(n), _x).subs(_x, x) + + def _eval_conjugate(self): + return self.func(self.args[0], self.args[1].conjugate()) + +#---------------------------------------------------------------------------- +# Jacobi polynomials +# + + +class jacobi(OrthogonalPolynomial): + r""" + Jacobi polynomial $P_n^{\left(\alpha, \beta\right)}(x)$. + + Explanation + =========== + + ``jacobi(n, alpha, beta, x)`` gives the $n$th Jacobi polynomial + in $x$, $P_n^{\left(\alpha, \beta\right)}(x)$. + + The Jacobi polynomials are orthogonal on $[-1, 1]$ with respect + to the weight $\left(1-x\right)^\alpha \left(1+x\right)^\beta$. + + Examples + ======== + + >>> from sympy import jacobi, S, conjugate, diff + >>> from sympy.abc import a, b, n, x + + >>> jacobi(0, a, b, x) + 1 + >>> jacobi(1, a, b, x) + a/2 - b/2 + x*(a/2 + b/2 + 1) + >>> jacobi(2, a, b, x) + a**2/8 - a*b/4 - a/8 + b**2/8 - b/8 + x**2*(a**2/8 + a*b/4 + 7*a/8 + b**2/8 + 7*b/8 + 3/2) + x*(a**2/4 + 3*a/4 - b**2/4 - 3*b/4) - 1/2 + + >>> jacobi(n, a, b, x) + jacobi(n, a, b, x) + + >>> jacobi(n, a, a, x) + RisingFactorial(a + 1, n)*gegenbauer(n, + a + 1/2, x)/RisingFactorial(2*a + 1, n) + + >>> jacobi(n, 0, 0, x) + legendre(n, x) + + >>> jacobi(n, S(1)/2, S(1)/2, x) + RisingFactorial(3/2, n)*chebyshevu(n, x)/factorial(n + 1) + + >>> jacobi(n, -S(1)/2, -S(1)/2, x) + RisingFactorial(1/2, n)*chebyshevt(n, x)/factorial(n) + + >>> jacobi(n, a, b, -x) + (-1)**n*jacobi(n, b, a, x) + + >>> jacobi(n, a, b, 0) + gamma(a + n + 1)*hyper((-n, -b - n), (a + 1,), -1)/(2**n*factorial(n)*gamma(a + 1)) + >>> jacobi(n, a, b, 1) + RisingFactorial(a + 1, n)/factorial(n) + + >>> conjugate(jacobi(n, a, b, x)) + jacobi(n, conjugate(a), conjugate(b), conjugate(x)) + + >>> diff(jacobi(n,a,b,x), x) + (a/2 + b/2 + n/2 + 1/2)*jacobi(n - 1, a + 1, b + 1, x) + + See Also + ======== + + gegenbauer, + chebyshevt_root, chebyshevu, chebyshevu_root, + legendre, assoc_legendre, + hermite, hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly, + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Jacobi_polynomials + .. [2] https://mathworld.wolfram.com/JacobiPolynomial.html + .. [3] https://functions.wolfram.com/Polynomials/JacobiP/ + + """ + + @classmethod + def eval(cls, n, a, b, x): + # Simplify to other polynomials + # P^{a, a}_n(x) + if a == b: + if a == Rational(-1, 2): + return RisingFactorial(S.Half, n) / factorial(n) * chebyshevt(n, x) + elif a.is_zero: + return legendre(n, x) + elif a == S.Half: + return RisingFactorial(3*S.Half, n) / factorial(n + 1) * chebyshevu(n, x) + else: + return RisingFactorial(a + 1, n) / RisingFactorial(2*a + 1, n) * gegenbauer(n, a + S.Half, x) + elif b == -a: + # P^{a, -a}_n(x) + return gamma(n + a + 1) / gamma(n + 1) * (1 + x)**(a/2) / (1 - x)**(a/2) * assoc_legendre(n, -a, x) + + if not n.is_Number: + # Symbolic result P^{a,b}_n(x) + # P^{a,b}_n(-x) ---> (-1)**n * P^{b,a}_n(-x) + if x.could_extract_minus_sign(): + return S.NegativeOne**n * jacobi(n, b, a, -x) + # We can evaluate for some special values of x + if x.is_zero: + return (2**(-n) * gamma(a + n + 1) / (gamma(a + 1) * factorial(n)) * + hyper([-b - n, -n], [a + 1], -1)) + if x == S.One: + return RisingFactorial(a + 1, n) / factorial(n) + elif x is S.Infinity: + if n.is_positive: + # Make sure a+b+2*n \notin Z + if (a + b + 2*n).is_integer: + raise ValueError("Error. a + b + 2*n should not be an integer.") + return RisingFactorial(a + b + n + 1, n) * S.Infinity + else: + # n is a given fixed integer, evaluate into polynomial + return jacobi_poly(n, a, b, x) + + def fdiff(self, argindex=4): + from sympy.concrete.summations import Sum + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt a + n, a, b, x = self.args + k = Dummy("k") + f1 = 1 / (a + b + n + k + 1) + f2 = ((a + b + 2*k + 1) * RisingFactorial(b + k + 1, n - k) / + ((n - k) * RisingFactorial(a + b + k + 1, n - k))) + return Sum(f1 * (jacobi(n, a, b, x) + f2*jacobi(k, a, b, x)), (k, 0, n - 1)) + elif argindex == 3: + # Diff wrt b + n, a, b, x = self.args + k = Dummy("k") + f1 = 1 / (a + b + n + k + 1) + f2 = (-1)**(n - k) * ((a + b + 2*k + 1) * RisingFactorial(a + k + 1, n - k) / + ((n - k) * RisingFactorial(a + b + k + 1, n - k))) + return Sum(f1 * (jacobi(n, a, b, x) + f2*jacobi(k, a, b, x)), (k, 0, n - 1)) + elif argindex == 4: + # Diff wrt x + n, a, b, x = self.args + return S.Half * (a + b + n + 1) * jacobi(n - 1, a + 1, b + 1, x) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, a, b, x, **kwargs): + from sympy.concrete.summations import Sum + # Make sure n \in N + if n.is_negative or n.is_integer is False: + raise ValueError("Error: n should be a non-negative integer.") + k = Dummy("k") + kern = (RisingFactorial(-n, k) * RisingFactorial(a + b + n + 1, k) * RisingFactorial(a + k + 1, n - k) / + factorial(k) * ((1 - x)/2)**k) + return 1 / factorial(n) * Sum(kern, (k, 0, n)) + + def _eval_rewrite_as_polynomial(self, n, a, b, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, a, b, x, **kwargs) + + def _eval_conjugate(self): + n, a, b, x = self.args + return self.func(n, a.conjugate(), b.conjugate(), x.conjugate()) + + +def jacobi_normalized(n, a, b, x): + r""" + Jacobi polynomial $P_n^{\left(\alpha, \beta\right)}(x)$. + + Explanation + =========== + + ``jacobi_normalized(n, alpha, beta, x)`` gives the $n$th + Jacobi polynomial in $x$, $P_n^{\left(\alpha, \beta\right)}(x)$. + + The Jacobi polynomials are orthogonal on $[-1, 1]$ with respect + to the weight $\left(1-x\right)^\alpha \left(1+x\right)^\beta$. + + This functions returns the polynomials normilzed: + + .. math:: + + \int_{-1}^{1} + P_m^{\left(\alpha, \beta\right)}(x) + P_n^{\left(\alpha, \beta\right)}(x) + (1-x)^{\alpha} (1+x)^{\beta} \mathrm{d}x + = \delta_{m,n} + + Examples + ======== + + >>> from sympy import jacobi_normalized + >>> from sympy.abc import n,a,b,x + + >>> jacobi_normalized(n, a, b, x) + jacobi(n, a, b, x)/sqrt(2**(a + b + 1)*gamma(a + n + 1)*gamma(b + n + 1)/((a + b + 2*n + 1)*factorial(n)*gamma(a + b + n + 1))) + + Parameters + ========== + + n : integer degree of polynomial + + a : alpha value + + b : beta value + + x : symbol + + See Also + ======== + + gegenbauer, + chebyshevt_root, chebyshevu, chebyshevu_root, + legendre, assoc_legendre, + hermite, hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly, + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Jacobi_polynomials + .. [2] https://mathworld.wolfram.com/JacobiPolynomial.html + .. [3] https://functions.wolfram.com/Polynomials/JacobiP/ + + """ + nfactor = (S(2)**(a + b + 1) * (gamma(n + a + 1) * gamma(n + b + 1)) + / (2*n + a + b + 1) / (factorial(n) * gamma(n + a + b + 1))) + + return jacobi(n, a, b, x) / sqrt(nfactor) + + +#---------------------------------------------------------------------------- +# Gegenbauer polynomials +# + + +class gegenbauer(OrthogonalPolynomial): + r""" + Gegenbauer polynomial $C_n^{\left(\alpha\right)}(x)$. + + Explanation + =========== + + ``gegenbauer(n, alpha, x)`` gives the $n$th Gegenbauer polynomial + in $x$, $C_n^{\left(\alpha\right)}(x)$. + + The Gegenbauer polynomials are orthogonal on $[-1, 1]$ with + respect to the weight $\left(1-x^2\right)^{\alpha-\frac{1}{2}}$. + + Examples + ======== + + >>> from sympy import gegenbauer, conjugate, diff + >>> from sympy.abc import n,a,x + >>> gegenbauer(0, a, x) + 1 + >>> gegenbauer(1, a, x) + 2*a*x + >>> gegenbauer(2, a, x) + -a + x**2*(2*a**2 + 2*a) + >>> gegenbauer(3, a, x) + x**3*(4*a**3/3 + 4*a**2 + 8*a/3) + x*(-2*a**2 - 2*a) + + >>> gegenbauer(n, a, x) + gegenbauer(n, a, x) + >>> gegenbauer(n, a, -x) + (-1)**n*gegenbauer(n, a, x) + + >>> gegenbauer(n, a, 0) + 2**n*sqrt(pi)*gamma(a + n/2)/(gamma(a)*gamma(1/2 - n/2)*gamma(n + 1)) + >>> gegenbauer(n, a, 1) + gamma(2*a + n)/(gamma(2*a)*gamma(n + 1)) + + >>> conjugate(gegenbauer(n, a, x)) + gegenbauer(n, conjugate(a), conjugate(x)) + + >>> diff(gegenbauer(n, a, x), x) + 2*a*gegenbauer(n - 1, a + 1, x) + + See Also + ======== + + jacobi, + chebyshevt_root, chebyshevu, chebyshevu_root, + legendre, assoc_legendre, + hermite, hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gegenbauer_polynomials + .. [2] https://mathworld.wolfram.com/GegenbauerPolynomial.html + .. [3] https://functions.wolfram.com/Polynomials/GegenbauerC3/ + + """ + + @classmethod + def eval(cls, n, a, x): + # For negative n the polynomials vanish + # See https://functions.wolfram.com/Polynomials/GegenbauerC3/03/01/03/0012/ + if n.is_negative: + return S.Zero + + # Some special values for fixed a + if a == S.Half: + return legendre(n, x) + elif a == S.One: + return chebyshevu(n, x) + elif a == S.NegativeOne: + return S.Zero + + if not n.is_Number: + # Handle this before the general sign extraction rule + if x == S.NegativeOne: + if (re(a) > S.Half) == True: + return S.ComplexInfinity + else: + return (cos(S.Pi*(a+n)) * sec(S.Pi*a) * gamma(2*a+n) / + (gamma(2*a) * gamma(n+1))) + + # Symbolic result C^a_n(x) + # C^a_n(-x) ---> (-1)**n * C^a_n(x) + if x.could_extract_minus_sign(): + return S.NegativeOne**n * gegenbauer(n, a, -x) + # We can evaluate for some special values of x + if x.is_zero: + return (2**n * sqrt(S.Pi) * gamma(a + S.Half*n) / + (gamma((1 - n)/2) * gamma(n + 1) * gamma(a)) ) + if x == S.One: + return gamma(2*a + n) / (gamma(2*a) * gamma(n + 1)) + elif x is S.Infinity: + if n.is_positive: + return RisingFactorial(a, n) * S.Infinity + else: + # n is a given fixed integer, evaluate into polynomial + return gegenbauer_poly(n, a, x) + + def fdiff(self, argindex=3): + from sympy.concrete.summations import Sum + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt a + n, a, x = self.args + k = Dummy("k") + factor1 = 2 * (1 + (-1)**(n - k)) * (k + a) / ((k + + n + 2*a) * (n - k)) + factor2 = 2*(k + 1) / ((k + 2*a) * (2*k + 2*a + 1)) + \ + 2 / (k + n + 2*a) + kern = factor1*gegenbauer(k, a, x) + factor2*gegenbauer(n, a, x) + return Sum(kern, (k, 0, n - 1)) + elif argindex == 3: + # Diff wrt x + n, a, x = self.args + return 2*a*gegenbauer(n - 1, a + 1, x) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, a, x, **kwargs): + from sympy.concrete.summations import Sum + k = Dummy("k") + kern = ((-1)**k * RisingFactorial(a, n - k) * (2*x)**(n - 2*k) / + (factorial(k) * factorial(n - 2*k))) + return Sum(kern, (k, 0, floor(n/2))) + + def _eval_rewrite_as_polynomial(self, n, a, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, a, x, **kwargs) + + def _eval_conjugate(self): + n, a, x = self.args + return self.func(n, a.conjugate(), x.conjugate()) + +#---------------------------------------------------------------------------- +# Chebyshev polynomials of first and second kind +# + + +class chebyshevt(OrthogonalPolynomial): + r""" + Chebyshev polynomial of the first kind, $T_n(x)$. + + Explanation + =========== + + ``chebyshevt(n, x)`` gives the $n$th Chebyshev polynomial (of the first + kind) in $x$, $T_n(x)$. + + The Chebyshev polynomials of the first kind are orthogonal on + $[-1, 1]$ with respect to the weight $\frac{1}{\sqrt{1-x^2}}$. + + Examples + ======== + + >>> from sympy import chebyshevt, diff + >>> from sympy.abc import n,x + >>> chebyshevt(0, x) + 1 + >>> chebyshevt(1, x) + x + >>> chebyshevt(2, x) + 2*x**2 - 1 + + >>> chebyshevt(n, x) + chebyshevt(n, x) + >>> chebyshevt(n, -x) + (-1)**n*chebyshevt(n, x) + >>> chebyshevt(-n, x) + chebyshevt(n, x) + + >>> chebyshevt(n, 0) + cos(pi*n/2) + >>> chebyshevt(n, -1) + (-1)**n + + >>> diff(chebyshevt(n, x), x) + n*chebyshevu(n - 1, x) + + See Also + ======== + + jacobi, gegenbauer, + chebyshevt_root, chebyshevu, chebyshevu_root, + legendre, assoc_legendre, + hermite, hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Chebyshev_polynomial + .. [2] https://mathworld.wolfram.com/ChebyshevPolynomialoftheFirstKind.html + .. [3] https://mathworld.wolfram.com/ChebyshevPolynomialoftheSecondKind.html + .. [4] https://functions.wolfram.com/Polynomials/ChebyshevT/ + .. [5] https://functions.wolfram.com/Polynomials/ChebyshevU/ + + """ + + _ortho_poly = staticmethod(chebyshevt_poly) + + @classmethod + def eval(cls, n, x): + if not n.is_Number: + # Symbolic result T_n(x) + # T_n(-x) ---> (-1)**n * T_n(x) + if x.could_extract_minus_sign(): + return S.NegativeOne**n * chebyshevt(n, -x) + # T_{-n}(x) ---> T_n(x) + if n.could_extract_minus_sign(): + return chebyshevt(-n, x) + # We can evaluate for some special values of x + if x.is_zero: + return cos(S.Half * S.Pi * n) + if x == S.One: + return S.One + elif x is S.Infinity: + return S.Infinity + else: + # n is a given fixed integer, evaluate into polynomial + if n.is_negative: + # T_{-n}(x) == T_n(x) + return cls._eval_at_order(-n, x) + else: + return cls._eval_at_order(n, x) + + def fdiff(self, argindex=2): + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt x + n, x = self.args + return n * chebyshevu(n - 1, x) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, x, **kwargs): + from sympy.concrete.summations import Sum + k = Dummy("k") + kern = binomial(n, 2*k) * (x**2 - 1)**k * x**(n - 2*k) + return Sum(kern, (k, 0, floor(n/2))) + + def _eval_rewrite_as_polynomial(self, n, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, x, **kwargs) + + +class chebyshevu(OrthogonalPolynomial): + r""" + Chebyshev polynomial of the second kind, $U_n(x)$. + + Explanation + =========== + + ``chebyshevu(n, x)`` gives the $n$th Chebyshev polynomial of the second + kind in x, $U_n(x)$. + + The Chebyshev polynomials of the second kind are orthogonal on + $[-1, 1]$ with respect to the weight $\sqrt{1-x^2}$. + + Examples + ======== + + >>> from sympy import chebyshevu, diff + >>> from sympy.abc import n,x + >>> chebyshevu(0, x) + 1 + >>> chebyshevu(1, x) + 2*x + >>> chebyshevu(2, x) + 4*x**2 - 1 + + >>> chebyshevu(n, x) + chebyshevu(n, x) + >>> chebyshevu(n, -x) + (-1)**n*chebyshevu(n, x) + >>> chebyshevu(-n, x) + -chebyshevu(n - 2, x) + + >>> chebyshevu(n, 0) + cos(pi*n/2) + >>> chebyshevu(n, 1) + n + 1 + + >>> diff(chebyshevu(n, x), x) + (-x*chebyshevu(n, x) + (n + 1)*chebyshevt(n + 1, x))/(x**2 - 1) + + See Also + ======== + + jacobi, gegenbauer, + chebyshevt, chebyshevt_root, chebyshevu_root, + legendre, assoc_legendre, + hermite, hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Chebyshev_polynomial + .. [2] https://mathworld.wolfram.com/ChebyshevPolynomialoftheFirstKind.html + .. [3] https://mathworld.wolfram.com/ChebyshevPolynomialoftheSecondKind.html + .. [4] https://functions.wolfram.com/Polynomials/ChebyshevT/ + .. [5] https://functions.wolfram.com/Polynomials/ChebyshevU/ + + """ + + _ortho_poly = staticmethod(chebyshevu_poly) + + @classmethod + def eval(cls, n, x): + if not n.is_Number: + # Symbolic result U_n(x) + # U_n(-x) ---> (-1)**n * U_n(x) + if x.could_extract_minus_sign(): + return S.NegativeOne**n * chebyshevu(n, -x) + # U_{-n}(x) ---> -U_{n-2}(x) + if n.could_extract_minus_sign(): + if n == S.NegativeOne: + # n can not be -1 here + return S.Zero + elif not (-n - 2).could_extract_minus_sign(): + return -chebyshevu(-n - 2, x) + # We can evaluate for some special values of x + if x.is_zero: + return cos(S.Half * S.Pi * n) + if x == S.One: + return S.One + n + elif x is S.Infinity: + return S.Infinity + else: + # n is a given fixed integer, evaluate into polynomial + if n.is_negative: + # U_{-n}(x) ---> -U_{n-2}(x) + if n == S.NegativeOne: + return S.Zero + else: + return -cls._eval_at_order(-n - 2, x) + else: + return cls._eval_at_order(n, x) + + def fdiff(self, argindex=2): + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt x + n, x = self.args + return ((n + 1) * chebyshevt(n + 1, x) - x * chebyshevu(n, x)) / (x**2 - 1) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, x, **kwargs): + from sympy.concrete.summations import Sum + k = Dummy("k") + kern = S.NegativeOne**k * factorial( + n - k) * (2*x)**(n - 2*k) / (factorial(k) * factorial(n - 2*k)) + return Sum(kern, (k, 0, floor(n/2))) + + def _eval_rewrite_as_polynomial(self, n, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, x, **kwargs) + + +class chebyshevt_root(DefinedFunction): + r""" + ``chebyshev_root(n, k)`` returns the $k$th root (indexed from zero) of + the $n$th Chebyshev polynomial of the first kind; that is, if + $0 \le k < n$, ``chebyshevt(n, chebyshevt_root(n, k)) == 0``. + + Examples + ======== + + >>> from sympy import chebyshevt, chebyshevt_root + >>> chebyshevt_root(3, 2) + -sqrt(3)/2 + >>> chebyshevt(3, chebyshevt_root(3, 2)) + 0 + + See Also + ======== + + jacobi, gegenbauer, + chebyshevt, chebyshevu, chebyshevu_root, + legendre, assoc_legendre, + hermite, hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + """ + + @classmethod + def eval(cls, n, k): + if not ((0 <= k) and (k < n)): + raise ValueError("must have 0 <= k < n, " + "got k = %s and n = %s" % (k, n)) + return cos(S.Pi*(2*k + 1)/(2*n)) + + +class chebyshevu_root(DefinedFunction): + r""" + ``chebyshevu_root(n, k)`` returns the $k$th root (indexed from zero) of the + $n$th Chebyshev polynomial of the second kind; that is, if $0 \le k < n$, + ``chebyshevu(n, chebyshevu_root(n, k)) == 0``. + + Examples + ======== + + >>> from sympy import chebyshevu, chebyshevu_root + >>> chebyshevu_root(3, 2) + -sqrt(2)/2 + >>> chebyshevu(3, chebyshevu_root(3, 2)) + 0 + + See Also + ======== + + chebyshevt, chebyshevt_root, chebyshevu, + legendre, assoc_legendre, + hermite, hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + """ + + + @classmethod + def eval(cls, n, k): + if not ((0 <= k) and (k < n)): + raise ValueError("must have 0 <= k < n, " + "got k = %s and n = %s" % (k, n)) + return cos(S.Pi*(k + 1)/(n + 1)) + +#---------------------------------------------------------------------------- +# Legendre polynomials and Associated Legendre polynomials +# + + +class legendre(OrthogonalPolynomial): + r""" + ``legendre(n, x)`` gives the $n$th Legendre polynomial of $x$, $P_n(x)$ + + Explanation + =========== + + The Legendre polynomials are orthogonal on $[-1, 1]$ with respect to + the constant weight 1. They satisfy $P_n(1) = 1$ for all $n$; further, + $P_n$ is odd for odd $n$ and even for even $n$. + + Examples + ======== + + >>> from sympy import legendre, diff + >>> from sympy.abc import x, n + >>> legendre(0, x) + 1 + >>> legendre(1, x) + x + >>> legendre(2, x) + 3*x**2/2 - 1/2 + >>> legendre(n, x) + legendre(n, x) + >>> diff(legendre(n,x), x) + n*(x*legendre(n, x) - legendre(n - 1, x))/(x**2 - 1) + + See Also + ======== + + jacobi, gegenbauer, + chebyshevt, chebyshevt_root, chebyshevu, chebyshevu_root, + assoc_legendre, + hermite, hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Legendre_polynomial + .. [2] https://mathworld.wolfram.com/LegendrePolynomial.html + .. [3] https://functions.wolfram.com/Polynomials/LegendreP/ + .. [4] https://functions.wolfram.com/Polynomials/LegendreP2/ + + """ + + _ortho_poly = staticmethod(legendre_poly) + + @classmethod + def eval(cls, n, x): + if not n.is_Number: + # Symbolic result L_n(x) + # L_n(-x) ---> (-1)**n * L_n(x) + if x.could_extract_minus_sign(): + return S.NegativeOne**n * legendre(n, -x) + # L_{-n}(x) ---> L_{n-1}(x) + if n.could_extract_minus_sign() and not(-n - 1).could_extract_minus_sign(): + return legendre(-n - S.One, x) + # We can evaluate for some special values of x + if x.is_zero: + return sqrt(S.Pi)/(gamma(S.Half - n/2)*gamma(S.One + n/2)) + elif x == S.One: + return S.One + elif x is S.Infinity: + return S.Infinity + else: + # n is a given fixed integer, evaluate into polynomial; + # L_{-n}(x) ---> L_{n-1}(x) + if n.is_negative: + n = -n - S.One + return cls._eval_at_order(n, x) + + def fdiff(self, argindex=2): + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt x + # Find better formula, this is unsuitable for x = +/-1 + # https://www.autodiff.org/ad16/Oral/Buecker_Legendre.pdf says + # at x = 1: + # n*(n + 1)/2 , m = 0 + # oo , m = 1 + # -(n-1)*n*(n+1)*(n+2)/4 , m = 2 + # 0 , m = 3, 4, ..., n + # + # at x = -1 + # (-1)**(n+1)*n*(n + 1)/2 , m = 0 + # (-1)**n*oo , m = 1 + # (-1)**n*(n-1)*n*(n+1)*(n+2)/4 , m = 2 + # 0 , m = 3, 4, ..., n + n, x = self.args + return n/(x**2 - 1)*(x*legendre(n, x) - legendre(n - 1, x)) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, x, **kwargs): + from sympy.concrete.summations import Sum + k = Dummy("k") + kern = S.NegativeOne**k*binomial(n, k)**2*((1 + x)/2)**(n - k)*((1 - x)/2)**k + return Sum(kern, (k, 0, n)) + + def _eval_rewrite_as_polynomial(self, n, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, x, **kwargs) + + +class assoc_legendre(DefinedFunction): + r""" + ``assoc_legendre(n, m, x)`` gives $P_n^m(x)$, where $n$ and $m$ are + the degree and order or an expression which is related to the nth + order Legendre polynomial, $P_n(x)$ in the following manner: + + .. math:: + P_n^m(x) = (-1)^m (1 - x^2)^{\frac{m}{2}} + \frac{\mathrm{d}^m P_n(x)}{\mathrm{d} x^m} + + Explanation + =========== + + Associated Legendre polynomials are orthogonal on $[-1, 1]$ with: + + - weight $= 1$ for the same $m$ and different $n$. + - weight $= \frac{1}{1-x^2}$ for the same $n$ and different $m$. + + Examples + ======== + + >>> from sympy import assoc_legendre + >>> from sympy.abc import x, m, n + >>> assoc_legendre(0,0, x) + 1 + >>> assoc_legendre(1,0, x) + x + >>> assoc_legendre(1,1, x) + -sqrt(1 - x**2) + >>> assoc_legendre(n,m,x) + assoc_legendre(n, m, x) + + See Also + ======== + + jacobi, gegenbauer, + chebyshevt, chebyshevt_root, chebyshevu, chebyshevu_root, + legendre, + hermite, hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Associated_Legendre_polynomials + .. [2] https://mathworld.wolfram.com/LegendrePolynomial.html + .. [3] https://functions.wolfram.com/Polynomials/LegendreP/ + .. [4] https://functions.wolfram.com/Polynomials/LegendreP2/ + + """ + + @classmethod + def _eval_at_order(cls, n, m): + P = legendre_poly(n, _x, polys=True).diff((_x, m)) + return S.NegativeOne**m * (1 - _x**2)**Rational(m, 2) * P.as_expr() + + @classmethod + def eval(cls, n, m, x): + if m.could_extract_minus_sign(): + # P^{-m}_n ---> F * P^m_n + return S.NegativeOne**(-m) * (factorial(m + n)/factorial(n - m)) * assoc_legendre(n, -m, x) + if m == 0: + # P^0_n ---> L_n + return legendre(n, x) + if x == 0: + return 2**m*sqrt(S.Pi) / (gamma((1 - m - n)/2)*gamma(1 - (m - n)/2)) + if n.is_Number and m.is_Number and n.is_integer and m.is_integer: + if n.is_negative: + raise ValueError("%s : 1st index must be nonnegative integer (got %r)" % (cls, n)) + if abs(m) > n: + raise ValueError("%s : abs('2nd index') must be <= '1st index' (got %r, %r)" % (cls, n, m)) + return cls._eval_at_order(int(n), abs(int(m))).subs(_x, x) + + def fdiff(self, argindex=3): + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt m + raise ArgumentIndexError(self, argindex) + elif argindex == 3: + # Diff wrt x + # Find better formula, this is unsuitable for x = 1 + n, m, x = self.args + return 1/(x**2 - 1)*(x*n*assoc_legendre(n, m, x) - (m + n)*assoc_legendre(n - 1, m, x)) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, m, x, **kwargs): + from sympy.concrete.summations import Sum + k = Dummy("k") + kern = factorial(2*n - 2*k)/(2**n*factorial(n - k)*factorial( + k)*factorial(n - 2*k - m))*S.NegativeOne**k*x**(n - m - 2*k) + return (1 - x**2)**(m/2) * Sum(kern, (k, 0, floor((n - m)*S.Half))) + + def _eval_rewrite_as_polynomial(self, n, m, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, m, x, **kwargs) + + def _eval_conjugate(self): + n, m, x = self.args + return self.func(n, m.conjugate(), x.conjugate()) + +#---------------------------------------------------------------------------- +# Hermite polynomials +# + + +class hermite(OrthogonalPolynomial): + r""" + ``hermite(n, x)`` gives the $n$th Hermite polynomial in $x$, $H_n(x)$. + + Explanation + =========== + + The Hermite polynomials are orthogonal on $(-\infty, \infty)$ + with respect to the weight $\exp\left(-x^2\right)$. + + Examples + ======== + + >>> from sympy import hermite, diff + >>> from sympy.abc import x, n + >>> hermite(0, x) + 1 + >>> hermite(1, x) + 2*x + >>> hermite(2, x) + 4*x**2 - 2 + >>> hermite(n, x) + hermite(n, x) + >>> diff(hermite(n,x), x) + 2*n*hermite(n - 1, x) + >>> hermite(n, -x) + (-1)**n*hermite(n, x) + + See Also + ======== + + jacobi, gegenbauer, + chebyshevt, chebyshevt_root, chebyshevu, chebyshevu_root, + legendre, assoc_legendre, + hermite_prob, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Hermite_polynomial + .. [2] https://mathworld.wolfram.com/HermitePolynomial.html + .. [3] https://functions.wolfram.com/Polynomials/HermiteH/ + + """ + + _ortho_poly = staticmethod(hermite_poly) + + @classmethod + def eval(cls, n, x): + if not n.is_Number: + # Symbolic result H_n(x) + # H_n(-x) ---> (-1)**n * H_n(x) + if x.could_extract_minus_sign(): + return S.NegativeOne**n * hermite(n, -x) + # We can evaluate for some special values of x + if x.is_zero: + return 2**n * sqrt(S.Pi) / gamma((S.One - n)/2) + elif x is S.Infinity: + return S.Infinity + else: + # n is a given fixed integer, evaluate into polynomial + if n.is_negative: + raise ValueError( + "The index n must be nonnegative integer (got %r)" % n) + else: + return cls._eval_at_order(n, x) + + def fdiff(self, argindex=2): + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt x + n, x = self.args + return 2*n*hermite(n - 1, x) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, x, **kwargs): + from sympy.concrete.summations import Sum + k = Dummy("k") + kern = S.NegativeOne**k / (factorial(k)*factorial(n - 2*k)) * (2*x)**(n - 2*k) + return factorial(n)*Sum(kern, (k, 0, floor(n/2))) + + def _eval_rewrite_as_polynomial(self, n, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, x, **kwargs) + + def _eval_rewrite_as_hermite_prob(self, n, x, **kwargs): + return sqrt(2)**n * hermite_prob(n, x*sqrt(2)) + + +class hermite_prob(OrthogonalPolynomial): + r""" + ``hermite_prob(n, x)`` gives the $n$th probabilist's Hermite polynomial + in $x$, $He_n(x)$. + + Explanation + =========== + + The probabilist's Hermite polynomials are orthogonal on $(-\infty, \infty)$ + with respect to the weight $\exp\left(-\frac{x^2}{2}\right)$. They are monic + polynomials, related to the plain Hermite polynomials (:py:class:`~.hermite`) by + + .. math :: He_n(x) = 2^{-n/2} H_n(x/\sqrt{2}) + + Examples + ======== + + >>> from sympy import hermite_prob, diff, I + >>> from sympy.abc import x, n + >>> hermite_prob(1, x) + x + >>> hermite_prob(5, x) + x**5 - 10*x**3 + 15*x + >>> diff(hermite_prob(n,x), x) + n*hermite_prob(n - 1, x) + >>> hermite_prob(n, -x) + (-1)**n*hermite_prob(n, x) + + The sum of absolute values of coefficients of $He_n(x)$ is the number of + matchings in the complete graph $K_n$ or telephone number, A000085 in the OEIS: + + >>> [hermite_prob(n,I) / I**n for n in range(11)] + [1, 1, 2, 4, 10, 26, 76, 232, 764, 2620, 9496] + + See Also + ======== + + jacobi, gegenbauer, + chebyshevt, chebyshevt_root, chebyshevu, chebyshevu_root, + legendre, assoc_legendre, + hermite, + laguerre, assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Hermite_polynomial + .. [2] https://mathworld.wolfram.com/HermitePolynomial.html + """ + + _ortho_poly = staticmethod(hermite_prob_poly) + + @classmethod + def eval(cls, n, x): + if not n.is_Number: + if x.could_extract_minus_sign(): + return S.NegativeOne**n * hermite_prob(n, -x) + if x.is_zero: + return sqrt(S.Pi) / gamma((S.One-n) / 2) + elif x is S.Infinity: + return S.Infinity + else: + if n.is_negative: + ValueError("n must be a nonnegative integer, not %r" % n) + else: + return cls._eval_at_order(n, x) + + def fdiff(self, argindex=2): + if argindex == 2: + n, x = self.args + return n*hermite_prob(n-1, x) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, x, **kwargs): + from sympy.concrete.summations import Sum + k = Dummy("k") + kern = (-S.Half)**k * x**(n-2*k) / (factorial(k) * factorial(n-2*k)) + return factorial(n)*Sum(kern, (k, 0, floor(n/2))) + + def _eval_rewrite_as_polynomial(self, n, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, x, **kwargs) + + def _eval_rewrite_as_hermite(self, n, x, **kwargs): + return sqrt(2)**(-n) * hermite(n, x/sqrt(2)) + + +#---------------------------------------------------------------------------- +# Laguerre polynomials +# + + +class laguerre(OrthogonalPolynomial): + r""" + Returns the $n$th Laguerre polynomial in $x$, $L_n(x)$. + + Examples + ======== + + >>> from sympy import laguerre, diff + >>> from sympy.abc import x, n + >>> laguerre(0, x) + 1 + >>> laguerre(1, x) + 1 - x + >>> laguerre(2, x) + x**2/2 - 2*x + 1 + >>> laguerre(3, x) + -x**3/6 + 3*x**2/2 - 3*x + 1 + + >>> laguerre(n, x) + laguerre(n, x) + + >>> diff(laguerre(n, x), x) + -assoc_laguerre(n - 1, 1, x) + + Parameters + ========== + + n : int + Degree of Laguerre polynomial. Must be `n \ge 0`. + + See Also + ======== + + jacobi, gegenbauer, + chebyshevt, chebyshevt_root, chebyshevu, chebyshevu_root, + legendre, assoc_legendre, + hermite, hermite_prob, + assoc_laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Laguerre_polynomial + .. [2] https://mathworld.wolfram.com/LaguerrePolynomial.html + .. [3] https://functions.wolfram.com/Polynomials/LaguerreL/ + .. [4] https://functions.wolfram.com/Polynomials/LaguerreL3/ + + """ + + _ortho_poly = staticmethod(laguerre_poly) + + @classmethod + def eval(cls, n, x): + if n.is_integer is False: + raise ValueError("Error: n should be an integer.") + if not n.is_Number: + # Symbolic result L_n(x) + # L_{n}(-x) ---> exp(-x) * L_{-n-1}(x) + # L_{-n}(x) ---> exp(x) * L_{n-1}(-x) + if n.could_extract_minus_sign() and not(-n - 1).could_extract_minus_sign(): + return exp(x)*laguerre(-n - 1, -x) + # We can evaluate for some special values of x + if x.is_zero: + return S.One + elif x is S.NegativeInfinity: + return S.Infinity + elif x is S.Infinity: + return S.NegativeOne**n * S.Infinity + else: + if n.is_negative: + return exp(x)*laguerre(-n - 1, -x) + else: + return cls._eval_at_order(n, x) + + def fdiff(self, argindex=2): + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt x + n, x = self.args + return -assoc_laguerre(n - 1, 1, x) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, x, **kwargs): + from sympy.concrete.summations import Sum + # Make sure n \in N_0 + if n.is_negative: + return exp(x) * self._eval_rewrite_as_Sum(-n - 1, -x, **kwargs) + if n.is_integer is False: + raise ValueError("Error: n should be an integer.") + k = Dummy("k") + kern = RisingFactorial(-n, k) / factorial(k)**2 * x**k + return Sum(kern, (k, 0, n)) + + def _eval_rewrite_as_polynomial(self, n, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, x, **kwargs) + + +class assoc_laguerre(OrthogonalPolynomial): + r""" + Returns the $n$th generalized Laguerre polynomial in $x$, $L_n(x)$. + + Examples + ======== + + >>> from sympy import assoc_laguerre, diff + >>> from sympy.abc import x, n, a + >>> assoc_laguerre(0, a, x) + 1 + >>> assoc_laguerre(1, a, x) + a - x + 1 + >>> assoc_laguerre(2, a, x) + a**2/2 + 3*a/2 + x**2/2 + x*(-a - 2) + 1 + >>> assoc_laguerre(3, a, x) + a**3/6 + a**2 + 11*a/6 - x**3/6 + x**2*(a/2 + 3/2) + + x*(-a**2/2 - 5*a/2 - 3) + 1 + + >>> assoc_laguerre(n, a, 0) + binomial(a + n, a) + + >>> assoc_laguerre(n, a, x) + assoc_laguerre(n, a, x) + + >>> assoc_laguerre(n, 0, x) + laguerre(n, x) + + >>> diff(assoc_laguerre(n, a, x), x) + -assoc_laguerre(n - 1, a + 1, x) + + >>> diff(assoc_laguerre(n, a, x), a) + Sum(assoc_laguerre(_k, a, x)/(-a + n), (_k, 0, n - 1)) + + Parameters + ========== + + n : int + Degree of Laguerre polynomial. Must be `n \ge 0`. + + alpha : Expr + Arbitrary expression. For ``alpha=0`` regular Laguerre + polynomials will be generated. + + See Also + ======== + + jacobi, gegenbauer, + chebyshevt, chebyshevt_root, chebyshevu, chebyshevu_root, + legendre, assoc_legendre, + hermite, hermite_prob, + laguerre, + sympy.polys.orthopolys.jacobi_poly + sympy.polys.orthopolys.gegenbauer_poly + sympy.polys.orthopolys.chebyshevt_poly + sympy.polys.orthopolys.chebyshevu_poly + sympy.polys.orthopolys.hermite_poly + sympy.polys.orthopolys.hermite_prob_poly + sympy.polys.orthopolys.legendre_poly + sympy.polys.orthopolys.laguerre_poly + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Laguerre_polynomial#Generalized_Laguerre_polynomials + .. [2] https://mathworld.wolfram.com/AssociatedLaguerrePolynomial.html + .. [3] https://functions.wolfram.com/Polynomials/LaguerreL/ + .. [4] https://functions.wolfram.com/Polynomials/LaguerreL3/ + + """ + + @classmethod + def eval(cls, n, alpha, x): + # L_{n}^{0}(x) ---> L_{n}(x) + if alpha.is_zero: + return laguerre(n, x) + + if not n.is_Number: + # We can evaluate for some special values of x + if x.is_zero: + return binomial(n + alpha, alpha) + elif x is S.Infinity and n > 0: + return S.NegativeOne**n * S.Infinity + elif x is S.NegativeInfinity and n > 0: + return S.Infinity + else: + # n is a given fixed integer, evaluate into polynomial + if n.is_negative: + raise ValueError( + "The index n must be nonnegative integer (got %r)" % n) + else: + return laguerre_poly(n, x, alpha) + + def fdiff(self, argindex=3): + from sympy.concrete.summations import Sum + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt alpha + n, alpha, x = self.args + k = Dummy("k") + return Sum(assoc_laguerre(k, alpha, x) / (n - alpha), (k, 0, n - 1)) + elif argindex == 3: + # Diff wrt x + n, alpha, x = self.args + return -assoc_laguerre(n - 1, alpha + 1, x) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_Sum(self, n, alpha, x, **kwargs): + from sympy.concrete.summations import Sum + # Make sure n \in N_0 + if n.is_negative or n.is_integer is False: + raise ValueError("Error: n should be a non-negative integer.") + k = Dummy("k") + kern = RisingFactorial( + -n, k) / (gamma(k + alpha + 1) * factorial(k)) * x**k + return gamma(n + alpha + 1) / factorial(n) * Sum(kern, (k, 0, n)) + + def _eval_rewrite_as_polynomial(self, n, alpha, x, **kwargs): + # This function is just kept for backwards compatibility + # but should not be used + return self._eval_rewrite_as_Sum(n, alpha, x, **kwargs) + + def _eval_conjugate(self): + n, alpha, x = self.args + return self.func(n, alpha.conjugate(), x.conjugate()) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/singularity_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/singularity_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..a69026e6e657b1131880b47cb32202b6825b7158 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/singularity_functions.py @@ -0,0 +1,235 @@ +from sympy.core import S, oo, diff +from sympy.core.function import DefinedFunction, ArgumentIndexError +from sympy.core.logic import fuzzy_not +from sympy.core.relational import Eq +from sympy.functions.elementary.complexes import im +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.special.delta_functions import Heaviside + +############################################################################### +############################# SINGULARITY FUNCTION ############################ +############################################################################### + + +class SingularityFunction(DefinedFunction): + r""" + Singularity functions are a class of discontinuous functions. + + Explanation + =========== + + Singularity functions take a variable, an offset, and an exponent as + arguments. These functions are represented using Macaulay brackets as: + + SingularityFunction(x, a, n) := ^n + + The singularity function will automatically evaluate to + ``Derivative(DiracDelta(x - a), x, -n - 1)`` if ``n < 0`` + and ``(x - a)**n*Heaviside(x - a, 1)`` if ``n >= 0``. + + Examples + ======== + + >>> from sympy import SingularityFunction, diff, Piecewise, DiracDelta, Heaviside, Symbol + >>> from sympy.abc import x, a, n + >>> SingularityFunction(x, a, n) + SingularityFunction(x, a, n) + >>> y = Symbol('y', positive=True) + >>> n = Symbol('n', nonnegative=True) + >>> SingularityFunction(y, -10, n) + (y + 10)**n + >>> y = Symbol('y', negative=True) + >>> SingularityFunction(y, 10, n) + 0 + >>> SingularityFunction(x, 4, -1).subs(x, 4) + oo + >>> SingularityFunction(x, 10, -2).subs(x, 10) + oo + >>> SingularityFunction(4, 1, 5) + 243 + >>> diff(SingularityFunction(x, 1, 5) + SingularityFunction(x, 1, 4), x) + 4*SingularityFunction(x, 1, 3) + 5*SingularityFunction(x, 1, 4) + >>> diff(SingularityFunction(x, 4, 0), x, 2) + SingularityFunction(x, 4, -2) + >>> SingularityFunction(x, 4, 5).rewrite(Piecewise) + Piecewise(((x - 4)**5, x >= 4), (0, True)) + >>> expr = SingularityFunction(x, a, n) + >>> y = Symbol('y', positive=True) + >>> n = Symbol('n', nonnegative=True) + >>> expr.subs({x: y, a: -10, n: n}) + (y + 10)**n + + The methods ``rewrite(DiracDelta)``, ``rewrite(Heaviside)``, and + ``rewrite('HeavisideDiracDelta')`` returns the same output. One can use any + of these methods according to their choice. + + >>> expr = SingularityFunction(x, 4, 5) + SingularityFunction(x, -3, -1) - SingularityFunction(x, 0, -2) + >>> expr.rewrite(Heaviside) + (x - 4)**5*Heaviside(x - 4, 1) + DiracDelta(x + 3) - DiracDelta(x, 1) + >>> expr.rewrite(DiracDelta) + (x - 4)**5*Heaviside(x - 4, 1) + DiracDelta(x + 3) - DiracDelta(x, 1) + >>> expr.rewrite('HeavisideDiracDelta') + (x - 4)**5*Heaviside(x - 4, 1) + DiracDelta(x + 3) - DiracDelta(x, 1) + + See Also + ======== + + DiracDelta, Heaviside + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Singularity_function + + """ + + is_real = True + + def fdiff(self, argindex=1): + """ + Returns the first derivative of a DiracDelta Function. + + Explanation + =========== + + The difference between ``diff()`` and ``fdiff()`` is: ``diff()`` is the + user-level function and ``fdiff()`` is an object method. ``fdiff()`` is + a convenience method available in the ``Function`` class. It returns + the derivative of the function without considering the chain rule. + ``diff(function, x)`` calls ``Function._eval_derivative`` which in turn + calls ``fdiff()`` internally to compute the derivative of the function. + + """ + + if argindex == 1: + x, a, n = self.args + if n in (S.Zero, S.NegativeOne, S(-2), S(-3)): + return self.func(x, a, n-1) + elif n.is_positive: + return n*self.func(x, a, n-1) + else: + raise ArgumentIndexError(self, argindex) + + @classmethod + def eval(cls, variable, offset, exponent): + """ + Returns a simplified form or a value of Singularity Function depending + on the argument passed by the object. + + Explanation + =========== + + The ``eval()`` method is automatically called when the + ``SingularityFunction`` class is about to be instantiated and it + returns either some simplified instance or the unevaluated instance + depending on the argument passed. In other words, ``eval()`` method is + not needed to be called explicitly, it is being called and evaluated + once the object is called. + + Examples + ======== + + >>> from sympy import SingularityFunction, Symbol, nan + >>> from sympy.abc import x, a, n + >>> SingularityFunction(x, a, n) + SingularityFunction(x, a, n) + >>> SingularityFunction(5, 3, 2) + 4 + >>> SingularityFunction(x, a, nan) + nan + >>> SingularityFunction(x, 3, 0).subs(x, 3) + 1 + >>> SingularityFunction(4, 1, 5) + 243 + >>> x = Symbol('x', positive = True) + >>> a = Symbol('a', negative = True) + >>> n = Symbol('n', nonnegative = True) + >>> SingularityFunction(x, a, n) + (-a + x)**n + >>> x = Symbol('x', negative = True) + >>> a = Symbol('a', positive = True) + >>> SingularityFunction(x, a, n) + 0 + + """ + + x = variable + a = offset + n = exponent + shift = (x - a) + + if fuzzy_not(im(shift).is_zero): + raise ValueError("Singularity Functions are defined only for Real Numbers.") + if fuzzy_not(im(n).is_zero): + raise ValueError("Singularity Functions are not defined for imaginary exponents.") + if shift is S.NaN or n is S.NaN: + return S.NaN + if (n + 4).is_negative: + raise ValueError("Singularity Functions are not defined for exponents less than -4.") + if shift.is_extended_negative: + return S.Zero + if n.is_nonnegative: + if shift.is_zero: # use literal 0 in case of Symbol('z', zero=True) + return S.Zero**n + if shift.is_extended_nonnegative: + return shift**n + if n in (S.NegativeOne, -2, -3, -4): + if shift.is_negative or shift.is_extended_positive: + return S.Zero + if shift.is_zero: + return oo + + def _eval_rewrite_as_Piecewise(self, *args, **kwargs): + ''' + Converts a Singularity Function expression into its Piecewise form. + + ''' + x, a, n = self.args + + if n in (S.NegativeOne, S(-2), S(-3), S(-4)): + return Piecewise((oo, Eq(x - a, 0)), (0, True)) + elif n.is_nonnegative: + return Piecewise(((x - a)**n, x - a >= 0), (0, True)) + + def _eval_rewrite_as_Heaviside(self, *args, **kwargs): + ''' + Rewrites a Singularity Function expression using Heavisides and DiracDeltas. + + ''' + x, a, n = self.args + + if n == -4: + return diff(Heaviside(x - a), x.free_symbols.pop(), 4) + if n == -3: + return diff(Heaviside(x - a), x.free_symbols.pop(), 3) + if n == -2: + return diff(Heaviside(x - a), x.free_symbols.pop(), 2) + if n == -1: + return diff(Heaviside(x - a), x.free_symbols.pop(), 1) + if n.is_nonnegative: + return (x - a)**n*Heaviside(x - a, 1) + + def _eval_as_leading_term(self, x, logx, cdir): + z, a, n = self.args + shift = (z - a).subs(x, 0) + if n < 0: + return S.Zero + elif n.is_zero and shift.is_zero: + return S.Zero if cdir == -1 else S.One + elif shift.is_positive: + return shift**n + return S.Zero + + def _eval_nseries(self, x, n, logx=None, cdir=0): + z, a, n = self.args + shift = (z - a).subs(x, 0) + if n < 0: + return S.Zero + elif n.is_zero and shift.is_zero: + return S.Zero if cdir == -1 else S.One + elif shift.is_positive: + return ((z - a)**n)._eval_nseries(x, n, logx=logx, cdir=cdir) + return S.Zero + + _eval_rewrite_as_DiracDelta = _eval_rewrite_as_Heaviside + _eval_rewrite_as_HeavisideDiracDelta = _eval_rewrite_as_Heaviside diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/spherical_harmonics.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/spherical_harmonics.py new file mode 100644 index 0000000000000000000000000000000000000000..541546b75e882b43c41814b5e92bb85ee41628d1 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/spherical_harmonics.py @@ -0,0 +1,334 @@ +from sympy.core.expr import Expr +from sympy.core.function import DefinedFunction, ArgumentIndexError +from sympy.core.numbers import I, pi +from sympy.core.singleton import S +from sympy.core.symbol import Dummy +from sympy.functions import assoc_legendre +from sympy.functions.combinatorial.factorials import factorial +from sympy.functions.elementary.complexes import Abs, conjugate +from sympy.functions.elementary.exponential import exp +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import sin, cos, cot + +_x = Dummy("x") + +class Ynm(DefinedFunction): + r""" + Spherical harmonics defined as + + .. math:: + Y_n^m(\theta, \varphi) := \sqrt{\frac{(2n+1)(n-m)!}{4\pi(n+m)!}} + \exp(i m \varphi) + \mathrm{P}_n^m\left(\cos(\theta)\right) + + Explanation + =========== + + ``Ynm()`` gives the spherical harmonic function of order $n$ and $m$ + in $\theta$ and $\varphi$, $Y_n^m(\theta, \varphi)$. The four + parameters are as follows: $n \geq 0$ an integer and $m$ an integer + such that $-n \leq m \leq n$ holds. The two angles are real-valued + with $\theta \in [0, \pi]$ and $\varphi \in [0, 2\pi]$. + + Examples + ======== + + >>> from sympy import Ynm, Symbol, simplify + >>> from sympy.abc import n,m + >>> theta = Symbol("theta") + >>> phi = Symbol("phi") + + >>> Ynm(n, m, theta, phi) + Ynm(n, m, theta, phi) + + Several symmetries are known, for the order: + + >>> Ynm(n, -m, theta, phi) + (-1)**m*exp(-2*I*m*phi)*Ynm(n, m, theta, phi) + + As well as for the angles: + + >>> Ynm(n, m, -theta, phi) + Ynm(n, m, theta, phi) + + >>> Ynm(n, m, theta, -phi) + exp(-2*I*m*phi)*Ynm(n, m, theta, phi) + + For specific integers $n$ and $m$ we can evaluate the harmonics + to more useful expressions: + + >>> simplify(Ynm(0, 0, theta, phi).expand(func=True)) + 1/(2*sqrt(pi)) + + >>> simplify(Ynm(1, -1, theta, phi).expand(func=True)) + sqrt(6)*exp(-I*phi)*sin(theta)/(4*sqrt(pi)) + + >>> simplify(Ynm(1, 0, theta, phi).expand(func=True)) + sqrt(3)*cos(theta)/(2*sqrt(pi)) + + >>> simplify(Ynm(1, 1, theta, phi).expand(func=True)) + -sqrt(6)*exp(I*phi)*sin(theta)/(4*sqrt(pi)) + + >>> simplify(Ynm(2, -2, theta, phi).expand(func=True)) + sqrt(30)*exp(-2*I*phi)*sin(theta)**2/(8*sqrt(pi)) + + >>> simplify(Ynm(2, -1, theta, phi).expand(func=True)) + sqrt(30)*exp(-I*phi)*sin(2*theta)/(8*sqrt(pi)) + + >>> simplify(Ynm(2, 0, theta, phi).expand(func=True)) + sqrt(5)*(3*cos(theta)**2 - 1)/(4*sqrt(pi)) + + >>> simplify(Ynm(2, 1, theta, phi).expand(func=True)) + -sqrt(30)*exp(I*phi)*sin(2*theta)/(8*sqrt(pi)) + + >>> simplify(Ynm(2, 2, theta, phi).expand(func=True)) + sqrt(30)*exp(2*I*phi)*sin(theta)**2/(8*sqrt(pi)) + + We can differentiate the functions with respect + to both angles: + + >>> from sympy import Ynm, Symbol, diff + >>> from sympy.abc import n,m + >>> theta = Symbol("theta") + >>> phi = Symbol("phi") + + >>> diff(Ynm(n, m, theta, phi), theta) + m*cot(theta)*Ynm(n, m, theta, phi) + sqrt((-m + n)*(m + n + 1))*exp(-I*phi)*Ynm(n, m + 1, theta, phi) + + >>> diff(Ynm(n, m, theta, phi), phi) + I*m*Ynm(n, m, theta, phi) + + Further we can compute the complex conjugation: + + >>> from sympy import Ynm, Symbol, conjugate + >>> from sympy.abc import n,m + >>> theta = Symbol("theta") + >>> phi = Symbol("phi") + + >>> conjugate(Ynm(n, m, theta, phi)) + (-1)**(2*m)*exp(-2*I*m*phi)*Ynm(n, m, theta, phi) + + To get back the well known expressions in spherical + coordinates, we use full expansion: + + >>> from sympy import Ynm, Symbol, expand_func + >>> from sympy.abc import n,m + >>> theta = Symbol("theta") + >>> phi = Symbol("phi") + + >>> expand_func(Ynm(n, m, theta, phi)) + sqrt((2*n + 1)*factorial(-m + n)/factorial(m + n))*exp(I*m*phi)*assoc_legendre(n, m, cos(theta))/(2*sqrt(pi)) + + See Also + ======== + + Ynm_c, Znm + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Spherical_harmonics + .. [2] https://mathworld.wolfram.com/SphericalHarmonic.html + .. [3] https://functions.wolfram.com/Polynomials/SphericalHarmonicY/ + .. [4] https://dlmf.nist.gov/14.30 + + """ + + @classmethod + def eval(cls, n, m, theta, phi): + # Handle negative index m and arguments theta, phi + if m.could_extract_minus_sign(): + m = -m + return S.NegativeOne**m * exp(-2*I*m*phi) * Ynm(n, m, theta, phi) + if theta.could_extract_minus_sign(): + theta = -theta + return Ynm(n, m, theta, phi) + if phi.could_extract_minus_sign(): + phi = -phi + return exp(-2*I*m*phi) * Ynm(n, m, theta, phi) + + # TODO Add more simplififcation here + + def _eval_expand_func(self, **hints): + n, m, theta, phi = self.args + rv = (sqrt((2*n + 1)/(4*pi) * factorial(n - m)/factorial(n + m)) * + exp(I*m*phi) * assoc_legendre(n, m, cos(theta))) + # We can do this because of the range of theta + return rv.subs(sqrt(-cos(theta)**2 + 1), sin(theta)) + + def fdiff(self, argindex=4): + if argindex == 1: + # Diff wrt n + raise ArgumentIndexError(self, argindex) + elif argindex == 2: + # Diff wrt m + raise ArgumentIndexError(self, argindex) + elif argindex == 3: + # Diff wrt theta + n, m, theta, phi = self.args + return (m * cot(theta) * Ynm(n, m, theta, phi) + + sqrt((n - m)*(n + m + 1)) * exp(-I*phi) * Ynm(n, m + 1, theta, phi)) + elif argindex == 4: + # Diff wrt phi + n, m, theta, phi = self.args + return I * m * Ynm(n, m, theta, phi) + else: + raise ArgumentIndexError(self, argindex) + + def _eval_rewrite_as_polynomial(self, n, m, theta, phi, **kwargs): + # TODO: Make sure n \in N + # TODO: Assert |m| <= n ortherwise we should return 0 + return self.expand(func=True) + + def _eval_rewrite_as_sin(self, n, m, theta, phi, **kwargs): + return self.rewrite(cos) + + def _eval_rewrite_as_cos(self, n, m, theta, phi, **kwargs): + # This method can be expensive due to extensive use of simplification! + from sympy.simplify import simplify, trigsimp + # TODO: Make sure n \in N + # TODO: Assert |m| <= n ortherwise we should return 0 + term = simplify(self.expand(func=True)) + # We can do this because of the range of theta + term = term.xreplace({Abs(sin(theta)):sin(theta)}) + return simplify(trigsimp(term)) + + def _eval_conjugate(self): + # TODO: Make sure theta \in R and phi \in R + n, m, theta, phi = self.args + return S.NegativeOne**m * self.func(n, -m, theta, phi) + + def as_real_imag(self, deep=True, **hints): + # TODO: Handle deep and hints + n, m, theta, phi = self.args + re = (sqrt((2*n + 1)/(4*pi) * factorial(n - m)/factorial(n + m)) * + cos(m*phi) * assoc_legendre(n, m, cos(theta))) + im = (sqrt((2*n + 1)/(4*pi) * factorial(n - m)/factorial(n + m)) * + sin(m*phi) * assoc_legendre(n, m, cos(theta))) + return (re, im) + + def _eval_evalf(self, prec): + # Note: works without this function by just calling + # mpmath for Legendre polynomials. But using + # the dedicated function directly is cleaner. + from mpmath import mp, workprec + n = self.args[0]._to_mpmath(prec) + m = self.args[1]._to_mpmath(prec) + theta = self.args[2]._to_mpmath(prec) + phi = self.args[3]._to_mpmath(prec) + with workprec(prec): + res = mp.spherharm(n, m, theta, phi) + return Expr._from_mpmath(res, prec) + + +def Ynm_c(n, m, theta, phi): + r""" + Conjugate spherical harmonics defined as + + .. math:: + \overline{Y_n^m(\theta, \varphi)} := (-1)^m Y_n^{-m}(\theta, \varphi). + + Examples + ======== + + >>> from sympy import Ynm_c, Symbol, simplify + >>> from sympy.abc import n,m + >>> theta = Symbol("theta") + >>> phi = Symbol("phi") + >>> Ynm_c(n, m, theta, phi) + (-1)**(2*m)*exp(-2*I*m*phi)*Ynm(n, m, theta, phi) + >>> Ynm_c(n, m, -theta, phi) + (-1)**(2*m)*exp(-2*I*m*phi)*Ynm(n, m, theta, phi) + + For specific integers $n$ and $m$ we can evaluate the harmonics + to more useful expressions: + + >>> simplify(Ynm_c(0, 0, theta, phi).expand(func=True)) + 1/(2*sqrt(pi)) + >>> simplify(Ynm_c(1, -1, theta, phi).expand(func=True)) + sqrt(6)*exp(I*(-phi + 2*conjugate(phi)))*sin(theta)/(4*sqrt(pi)) + + See Also + ======== + + Ynm, Znm + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Spherical_harmonics + .. [2] https://mathworld.wolfram.com/SphericalHarmonic.html + .. [3] https://functions.wolfram.com/Polynomials/SphericalHarmonicY/ + + """ + return conjugate(Ynm(n, m, theta, phi)) + + +class Znm(DefinedFunction): + r""" + Real spherical harmonics defined as + + .. math:: + + Z_n^m(\theta, \varphi) := + \begin{cases} + \frac{Y_n^m(\theta, \varphi) + \overline{Y_n^m(\theta, \varphi)}}{\sqrt{2}} &\quad m > 0 \\ + Y_n^m(\theta, \varphi) &\quad m = 0 \\ + \frac{Y_n^m(\theta, \varphi) - \overline{Y_n^m(\theta, \varphi)}}{i \sqrt{2}} &\quad m < 0 \\ + \end{cases} + + which gives in simplified form + + .. math:: + + Z_n^m(\theta, \varphi) = + \begin{cases} + \frac{Y_n^m(\theta, \varphi) + (-1)^m Y_n^{-m}(\theta, \varphi)}{\sqrt{2}} &\quad m > 0 \\ + Y_n^m(\theta, \varphi) &\quad m = 0 \\ + \frac{Y_n^m(\theta, \varphi) - (-1)^m Y_n^{-m}(\theta, \varphi)}{i \sqrt{2}} &\quad m < 0 \\ + \end{cases} + + Examples + ======== + + >>> from sympy import Znm, Symbol, simplify + >>> from sympy.abc import n, m + >>> theta = Symbol("theta") + >>> phi = Symbol("phi") + >>> Znm(n, m, theta, phi) + Znm(n, m, theta, phi) + + For specific integers n and m we can evaluate the harmonics + to more useful expressions: + + >>> simplify(Znm(0, 0, theta, phi).expand(func=True)) + 1/(2*sqrt(pi)) + >>> simplify(Znm(1, 1, theta, phi).expand(func=True)) + -sqrt(3)*sin(theta)*cos(phi)/(2*sqrt(pi)) + >>> simplify(Znm(2, 1, theta, phi).expand(func=True)) + -sqrt(15)*sin(2*theta)*cos(phi)/(4*sqrt(pi)) + + See Also + ======== + + Ynm, Ynm_c + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Spherical_harmonics + .. [2] https://mathworld.wolfram.com/SphericalHarmonic.html + .. [3] https://functions.wolfram.com/Polynomials/SphericalHarmonicY/ + + """ + + @classmethod + def eval(cls, n, m, theta, phi): + if m.is_positive: + zz = (Ynm(n, m, theta, phi) + Ynm_c(n, m, theta, phi)) / sqrt(2) + return zz + elif m.is_zero: + return Ynm(n, m, theta, phi) + elif m.is_negative: + zz = (Ynm(n, m, theta, phi) - Ynm_c(n, m, theta, phi)) / (sqrt(2)*I) + return zz diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tensor_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tensor_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..6d996a58cbc8320620c9a1f6e68529c3b5e99aef --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tensor_functions.py @@ -0,0 +1,474 @@ +from math import prod + +from sympy.core import S, Integer +from sympy.core.function import DefinedFunction +from sympy.core.logic import fuzzy_not +from sympy.core.relational import Ne +from sympy.core.sorting import default_sort_key +from sympy.external.gmpy import SYMPY_INTS +from sympy.functions.combinatorial.factorials import factorial +from sympy.functions.elementary.piecewise import Piecewise +from sympy.utilities.iterables import has_dups + +############################################################################### +###################### Kronecker Delta, Levi-Civita etc. ###################### +############################################################################### + + +def Eijk(*args, **kwargs): + """ + Represent the Levi-Civita symbol. + + This is a compatibility wrapper to ``LeviCivita()``. + + See Also + ======== + + LeviCivita + + """ + return LeviCivita(*args, **kwargs) + + +def eval_levicivita(*args): + """Evaluate Levi-Civita symbol.""" + n = len(args) + return prod( + prod(args[j] - args[i] for j in range(i + 1, n)) + / factorial(i) for i in range(n)) + # converting factorial(i) to int is slightly faster + + +class LeviCivita(DefinedFunction): + """ + Represent the Levi-Civita symbol. + + Explanation + =========== + + For even permutations of indices it returns 1, for odd permutations -1, and + for everything else (a repeated index) it returns 0. + + Thus it represents an alternating pseudotensor. + + Examples + ======== + + >>> from sympy import LeviCivita + >>> from sympy.abc import i, j, k + >>> LeviCivita(1, 2, 3) + 1 + >>> LeviCivita(1, 3, 2) + -1 + >>> LeviCivita(1, 2, 2) + 0 + >>> LeviCivita(i, j, k) + LeviCivita(i, j, k) + >>> LeviCivita(i, j, i) + 0 + + See Also + ======== + + Eijk + + """ + + is_integer = True + + @classmethod + def eval(cls, *args): + if all(isinstance(a, (SYMPY_INTS, Integer)) for a in args): + return eval_levicivita(*args) + if has_dups(args): + return S.Zero + + def doit(self, **hints): + return eval_levicivita(*self.args) + + +class KroneckerDelta(DefinedFunction): + """ + The discrete, or Kronecker, delta function. + + Explanation + =========== + + A function that takes in two integers $i$ and $j$. It returns $0$ if $i$ + and $j$ are not equal, or it returns $1$ if $i$ and $j$ are equal. + + Examples + ======== + + An example with integer indices: + + >>> from sympy import KroneckerDelta + >>> KroneckerDelta(1, 2) + 0 + >>> KroneckerDelta(3, 3) + 1 + + Symbolic indices: + + >>> from sympy.abc import i, j, k + >>> KroneckerDelta(i, j) + KroneckerDelta(i, j) + >>> KroneckerDelta(i, i) + 1 + >>> KroneckerDelta(i, i + 1) + 0 + >>> KroneckerDelta(i, i + 1 + k) + KroneckerDelta(i, i + k + 1) + + Parameters + ========== + + i : Number, Symbol + The first index of the delta function. + j : Number, Symbol + The second index of the delta function. + + See Also + ======== + + eval + DiracDelta + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Kronecker_delta + + """ + + is_integer = True + + @classmethod + def eval(cls, i, j, delta_range=None): + """ + Evaluates the discrete delta function. + + Examples + ======== + + >>> from sympy import KroneckerDelta + >>> from sympy.abc import i, j, k + + >>> KroneckerDelta(i, j) + KroneckerDelta(i, j) + >>> KroneckerDelta(i, i) + 1 + >>> KroneckerDelta(i, i + 1) + 0 + >>> KroneckerDelta(i, i + 1 + k) + KroneckerDelta(i, i + k + 1) + + # indirect doctest + + """ + + if delta_range is not None: + dinf, dsup = delta_range + if (dinf - i > 0) == True: + return S.Zero + if (dinf - j > 0) == True: + return S.Zero + if (dsup - i < 0) == True: + return S.Zero + if (dsup - j < 0) == True: + return S.Zero + + diff = i - j + if diff.is_zero: + return S.One + elif fuzzy_not(diff.is_zero): + return S.Zero + + if i.assumptions0.get("below_fermi") and \ + j.assumptions0.get("above_fermi"): + return S.Zero + if j.assumptions0.get("below_fermi") and \ + i.assumptions0.get("above_fermi"): + return S.Zero + # to make KroneckerDelta canonical + # following lines will check if inputs are in order + # if not, will return KroneckerDelta with correct order + if default_sort_key(j) < default_sort_key(i): + if delta_range: + return cls(j, i, delta_range) + else: + return cls(j, i) + + @property + def delta_range(self): + if len(self.args) > 2: + return self.args[2] + + def _eval_power(self, expt): + if expt.is_positive: + return self + if expt.is_negative and expt is not S.NegativeOne: + return 1/self + + @property + def is_above_fermi(self): + """ + True if Delta can be non-zero above fermi. + + Examples + ======== + + >>> from sympy import KroneckerDelta, Symbol + >>> a = Symbol('a', above_fermi=True) + >>> i = Symbol('i', below_fermi=True) + >>> p = Symbol('p') + >>> q = Symbol('q') + >>> KroneckerDelta(p, a).is_above_fermi + True + >>> KroneckerDelta(p, i).is_above_fermi + False + >>> KroneckerDelta(p, q).is_above_fermi + True + + See Also + ======== + + is_below_fermi, is_only_below_fermi, is_only_above_fermi + + """ + if self.args[0].assumptions0.get("below_fermi"): + return False + if self.args[1].assumptions0.get("below_fermi"): + return False + return True + + @property + def is_below_fermi(self): + """ + True if Delta can be non-zero below fermi. + + Examples + ======== + + >>> from sympy import KroneckerDelta, Symbol + >>> a = Symbol('a', above_fermi=True) + >>> i = Symbol('i', below_fermi=True) + >>> p = Symbol('p') + >>> q = Symbol('q') + >>> KroneckerDelta(p, a).is_below_fermi + False + >>> KroneckerDelta(p, i).is_below_fermi + True + >>> KroneckerDelta(p, q).is_below_fermi + True + + See Also + ======== + + is_above_fermi, is_only_above_fermi, is_only_below_fermi + + """ + if self.args[0].assumptions0.get("above_fermi"): + return False + if self.args[1].assumptions0.get("above_fermi"): + return False + return True + + @property + def is_only_above_fermi(self): + """ + True if Delta is restricted to above fermi. + + Examples + ======== + + >>> from sympy import KroneckerDelta, Symbol + >>> a = Symbol('a', above_fermi=True) + >>> i = Symbol('i', below_fermi=True) + >>> p = Symbol('p') + >>> q = Symbol('q') + >>> KroneckerDelta(p, a).is_only_above_fermi + True + >>> KroneckerDelta(p, q).is_only_above_fermi + False + >>> KroneckerDelta(p, i).is_only_above_fermi + False + + See Also + ======== + + is_above_fermi, is_below_fermi, is_only_below_fermi + + """ + return ( self.args[0].assumptions0.get("above_fermi") + or + self.args[1].assumptions0.get("above_fermi") + ) or False + + @property + def is_only_below_fermi(self): + """ + True if Delta is restricted to below fermi. + + Examples + ======== + + >>> from sympy import KroneckerDelta, Symbol + >>> a = Symbol('a', above_fermi=True) + >>> i = Symbol('i', below_fermi=True) + >>> p = Symbol('p') + >>> q = Symbol('q') + >>> KroneckerDelta(p, i).is_only_below_fermi + True + >>> KroneckerDelta(p, q).is_only_below_fermi + False + >>> KroneckerDelta(p, a).is_only_below_fermi + False + + See Also + ======== + + is_above_fermi, is_below_fermi, is_only_above_fermi + + """ + return ( self.args[0].assumptions0.get("below_fermi") + or + self.args[1].assumptions0.get("below_fermi") + ) or False + + @property + def indices_contain_equal_information(self): + """ + Returns True if indices are either both above or below fermi. + + Examples + ======== + + >>> from sympy import KroneckerDelta, Symbol + >>> a = Symbol('a', above_fermi=True) + >>> i = Symbol('i', below_fermi=True) + >>> p = Symbol('p') + >>> q = Symbol('q') + >>> KroneckerDelta(p, q).indices_contain_equal_information + True + >>> KroneckerDelta(p, q+1).indices_contain_equal_information + True + >>> KroneckerDelta(i, p).indices_contain_equal_information + False + + """ + if (self.args[0].assumptions0.get("below_fermi") and + self.args[1].assumptions0.get("below_fermi")): + return True + if (self.args[0].assumptions0.get("above_fermi") + and self.args[1].assumptions0.get("above_fermi")): + return True + + # if both indices are general we are True, else false + return self.is_below_fermi and self.is_above_fermi + + @property + def preferred_index(self): + """ + Returns the index which is preferred to keep in the final expression. + + Explanation + =========== + + The preferred index is the index with more information regarding fermi + level. If indices contain the same information, 'a' is preferred before + 'b'. + + Examples + ======== + + >>> from sympy import KroneckerDelta, Symbol + >>> a = Symbol('a', above_fermi=True) + >>> i = Symbol('i', below_fermi=True) + >>> j = Symbol('j', below_fermi=True) + >>> p = Symbol('p') + >>> KroneckerDelta(p, i).preferred_index + i + >>> KroneckerDelta(p, a).preferred_index + a + >>> KroneckerDelta(i, j).preferred_index + i + + See Also + ======== + + killable_index + + """ + if self._get_preferred_index(): + return self.args[1] + else: + return self.args[0] + + @property + def killable_index(self): + """ + Returns the index which is preferred to substitute in the final + expression. + + Explanation + =========== + + The index to substitute is the index with less information regarding + fermi level. If indices contain the same information, 'a' is preferred + before 'b'. + + Examples + ======== + + >>> from sympy import KroneckerDelta, Symbol + >>> a = Symbol('a', above_fermi=True) + >>> i = Symbol('i', below_fermi=True) + >>> j = Symbol('j', below_fermi=True) + >>> p = Symbol('p') + >>> KroneckerDelta(p, i).killable_index + p + >>> KroneckerDelta(p, a).killable_index + p + >>> KroneckerDelta(i, j).killable_index + j + + See Also + ======== + + preferred_index + + """ + if self._get_preferred_index(): + return self.args[0] + else: + return self.args[1] + + def _get_preferred_index(self): + """ + Returns the index which is preferred to keep in the final expression. + + The preferred index is the index with more information regarding fermi + level. If indices contain the same information, index 0 is returned. + + """ + if not self.is_above_fermi: + if self.args[0].assumptions0.get("below_fermi"): + return 0 + else: + return 1 + elif not self.is_below_fermi: + if self.args[0].assumptions0.get("above_fermi"): + return 0 + else: + return 1 + else: + return 0 + + @property + def indices(self): + return self.args[0:2] + + def _eval_rewrite_as_Piecewise(self, *args, **kwargs): + i, j = args + return Piecewise((0, Ne(i, j)), (1, True)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_bessel.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_bessel.py new file mode 100644 index 0000000000000000000000000000000000000000..ccd1ce88ca9dea15f065e7c57d488498b8f79f4e --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_bessel.py @@ -0,0 +1,807 @@ +from itertools import product + +from sympy.concrete.summations import Sum +from sympy.core.function import (diff, expand_func) +from sympy.core.numbers import (I, Rational, oo, pi) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.complexes import (conjugate, polar_lift) +from sympy.functions.elementary.exponential import (exp, exp_polar, log) +from sympy.functions.elementary.hyperbolic import (cosh, sinh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (cos, sin) +from sympy.functions.special.bessel import (besseli, besselj, besselk, bessely, hankel1, hankel2, hn1, hn2, jn, jn_zeros, yn) +from sympy.functions.special.gamma_functions import (gamma, uppergamma) +from sympy.functions.special.hyper import hyper +from sympy.integrals.integrals import Integral +from sympy.series.order import O +from sympy.series.series import series +from sympy.functions.special.bessel import (airyai, airybi, + airyaiprime, airybiprime, marcumq) +from sympy.core.random import (random_complex_number as randcplx, + verify_numerically as tn, + test_derivative_numerically as td, + _randint) +from sympy.simplify import besselsimp +from sympy.testing.pytest import raises, slow + +from sympy.abc import z, n, k, x + +randint = _randint() + + +def test_bessel_rand(): + for f in [besselj, bessely, besseli, besselk, hankel1, hankel2]: + assert td(f(randcplx(), z), z) + + for f in [jn, yn, hn1, hn2]: + assert td(f(randint(-10, 10), z), z) + + +def test_bessel_twoinputs(): + for f in [besselj, bessely, besseli, besselk, hankel1, hankel2, jn, yn]: + raises(TypeError, lambda: f(1)) + raises(TypeError, lambda: f(1, 2, 3)) + + +def test_besselj_leading_term(): + assert besselj(0, x).as_leading_term(x) == 1 + assert besselj(1, sin(x)).as_leading_term(x) == x/2 + assert besselj(1, 2*sqrt(x)).as_leading_term(x) == sqrt(x) + + # https://github.com/sympy/sympy/issues/21701 + assert (besselj(z, x)/x**z).as_leading_term(x) == 1/(2**z*gamma(z + 1)) + + +def test_bessely_leading_term(): + assert bessely(0, x).as_leading_term(x) == (2*log(x) - 2*log(2) + 2*S.EulerGamma)/pi + assert bessely(1, sin(x)).as_leading_term(x) == -2/(pi*x) + assert bessely(1, 2*sqrt(x)).as_leading_term(x) == -1/(pi*sqrt(x)) + + +def test_besseli_leading_term(): + assert besseli(0, x).as_leading_term(x) == 1 + assert besseli(1, sin(x)).as_leading_term(x) == x/2 + assert besseli(1, 2*sqrt(x)).as_leading_term(x) == sqrt(x) + + +def test_besselk_leading_term(): + assert besselk(0, x).as_leading_term(x) == -log(x) - S.EulerGamma + log(2) + assert besselk(1, sin(x)).as_leading_term(x) == 1/x + assert besselk(1, 2*sqrt(x)).as_leading_term(x) == 1/(2*sqrt(x)) + assert besselk(S(5)/3, x).as_leading_term(x) == 2**(S(2)/3)*gamma(S(5)/3)/x**(S(5)/3) + assert besselk(S(2)/3, x).as_leading_term(x) == besselk(-S(2)/3, x).as_leading_term(x) + assert besselk(1,cos(x)).as_leading_term(x) == besselk(1,1) + assert besselk(3,1/x).as_leading_term(x) == sqrt(pi)*exp(-(1/x))/sqrt(2/x) + assert besselk(3,1/sin(x)).as_leading_term(x) == sqrt(pi)*exp(-(1/x))/sqrt(2/x) + + nz = Symbol("nz", nonzero=True) + assert besselk(nz, x).as_leading_term(x).subs({nz:S(5)/7}) == besselk(S(5)/7, x).series(x).as_leading_term(x) + assert besselk(nz, x).as_leading_term(x).subs({nz:S(-15)/7}) == besselk(S(-15)/7, x).series(x).as_leading_term(x) + assert besselk(nz, x).as_leading_term(x).subs({nz:3}) == besselk(3, x).series(x).as_leading_term(x) + assert besselk(nz, x).as_leading_term(x).subs({nz:-2}) == besselk(-2, x).series(x).as_leading_term(x) + + +def test_besselj_series(): + assert besselj(0, x).series(x) == 1 - x**2/4 + x**4/64 + O(x**6) + assert besselj(0, x**(1.1)).series(x) == 1 + x**4.4/64 - x**2.2/4 + O(x**6) + assert besselj(0, x**2 + x).series(x) == 1 - x**2/4 - x**3/2\ + - 15*x**4/64 + x**5/16 + O(x**6) + assert besselj(0, sqrt(x) + x).series(x, n=4) == 1 - x/4 - 15*x**2/64\ + + 215*x**3/2304 - x**Rational(3, 2)/2 + x**Rational(5, 2)/16\ + + 23*x**Rational(7, 2)/384 + O(x**4) + assert besselj(0, x/(1 - x)).series(x) == 1 - x**2/4 - x**3/2 - 47*x**4/64\ + - 15*x**5/16 + O(x**6) + assert besselj(0, log(1 + x)).series(x) == 1 - x**2/4 + x**3/4\ + - 41*x**4/192 + 17*x**5/96 + O(x**6) + assert besselj(1, sin(x)).series(x) == x/2 - 7*x**3/48 + 73*x**5/1920 + O(x**6) + assert besselj(1, 2*sqrt(x)).series(x) == sqrt(x) - x**Rational(3, 2)/2\ + + x**Rational(5, 2)/12 - x**Rational(7, 2)/144 + x**Rational(9, 2)/2880\ + - x**Rational(11, 2)/86400 + O(x**6) + assert besselj(-2, sin(x)).series(x, n=4) == besselj(2, sin(x)).series(x, n=4) + + +def test_bessely_series(): + const = 2*S.EulerGamma/pi - 2*log(2)/pi + 2*log(x)/pi + assert bessely(0, x).series(x, n=4) == const + x**2*(-log(x)/(2*pi)\ + + (2 - 2*S.EulerGamma)/(4*pi) + log(2)/(2*pi)) + O(x**4*log(x)) + assert bessely(1, x).series(x, n=4) == -2/(pi*x) + x*(log(x)/pi - log(2)/pi - \ + (1 - 2*S.EulerGamma)/(2*pi)) + x**3*(-log(x)/(8*pi) + \ + (S(5)/2 - 2*S.EulerGamma)/(16*pi) + log(2)/(8*pi)) + O(x**4*log(x)) + assert bessely(2, x).series(x, n=4) == -4/(pi*x**2) - 1/pi + x**2*(log(x)/(4*pi) - \ + log(2)/(4*pi) - (S(3)/2 - 2*S.EulerGamma)/(8*pi)) + O(x**4*log(x)) + assert bessely(3, x).series(x, n=4) == -16/(pi*x**3) - 2/(pi*x) - \ + x/(4*pi) + x**3*(log(x)/(24*pi) - log(2)/(24*pi) - \ + (S(11)/6 - 2*S.EulerGamma)/(48*pi)) + O(x**4*log(x)) + assert bessely(0, x**(1.1)).series(x, n=4) == 2*S.EulerGamma/pi\ + - 2*log(2)/pi + 2.2*log(x)/pi + x**2.2*(-0.55*log(x)/pi\ + + (2 - 2*S.EulerGamma)/(4*pi) + log(2)/(2*pi)) + O(x**4*log(x)) + assert bessely(0, x**2 + x).series(x, n=4) == \ + const - (2 - 2*S.EulerGamma)*(-x**3/(2*pi) - x**2/(4*pi)) + 2*x/pi\ + + x**2*(-log(x)/(2*pi) - 1/pi + log(2)/(2*pi))\ + + x**3*(-log(x)/pi + 1/(6*pi) + log(2)/pi) + O(x**4*log(x)) + assert bessely(0, x/(1 - x)).series(x, n=3) == const\ + + 2*x/pi + x**2*(-log(x)/(2*pi) + (2 - 2*S.EulerGamma)/(4*pi)\ + + log(2)/(2*pi) + 1/pi) + O(x**3*log(x)) + assert bessely(0, log(1 + x)).series(x, n=3) == const\ + - x/pi + x**2*(-log(x)/(2*pi) + (2 - 2*S.EulerGamma)/(4*pi)\ + + log(2)/(2*pi) + 5/(12*pi)) + O(x**3*log(x)) + assert bessely(1, sin(x)).series(x, n=4) == -1/(pi*(-x**3/12 + x/2)) - \ + (1 - 2*S.EulerGamma)*(-x**3/12 + x/2)/pi + x*(log(x)/pi - log(2)/pi) + \ + x**3*(-7*log(x)/(24*pi) - 1/(6*pi) + (S(5)/2 - 2*S.EulerGamma)/(16*pi) + + 7*log(2)/(24*pi)) + O(x**4*log(x)) + assert bessely(1, 2*sqrt(x)).series(x, n=3) == -1/(pi*sqrt(x)) + \ + sqrt(x)*(log(x)/pi - (1 - 2*S.EulerGamma)/pi) + x**(S(3)/2)*(-log(x)/(2*pi) + \ + (S(5)/2 - 2*S.EulerGamma)/(2*pi)) + x**(S(5)/2)*(log(x)/(12*pi) - \ + (S(10)/3 - 2*S.EulerGamma)/(12*pi)) + O(x**3*log(x)) + assert bessely(-2, sin(x)).series(x, n=4) == bessely(2, sin(x)).series(x, n=4) + + +def test_besseli_series(): + assert besseli(0, x).series(x) == 1 + x**2/4 + x**4/64 + O(x**6) + assert besseli(0, x**(1.1)).series(x) == 1 + x**4.4/64 + x**2.2/4 + O(x**6) + assert besseli(0, x**2 + x).series(x) == 1 + x**2/4 + x**3/2 + 17*x**4/64 + \ + x**5/16 + O(x**6) + assert besseli(0, sqrt(x) + x).series(x, n=4) == 1 + x/4 + 17*x**2/64 + \ + 217*x**3/2304 + x**(S(3)/2)/2 + x**(S(5)/2)/16 + 25*x**(S(7)/2)/384 + O(x**4) + assert besseli(0, x/(1 - x)).series(x) == 1 + x**2/4 + x**3/2 + 49*x**4/64 + \ + 17*x**5/16 + O(x**6) + assert besseli(0, log(1 + x)).series(x) == 1 + x**2/4 - x**3/4 + 47*x**4/192 - \ + 23*x**5/96 + O(x**6) + assert besseli(1, sin(x)).series(x) == x/2 - x**3/48 - 47*x**5/1920 + O(x**6) + assert besseli(1, 2*sqrt(x)).series(x) == sqrt(x) + x**(S(3)/2)/2 + x**(S(5)/2)/12 + \ + x**(S(7)/2)/144 + x**(S(9)/2)/2880 + x**(S(11)/2)/86400 + O(x**6) + assert besseli(-2, sin(x)).series(x, n=4) == besseli(2, sin(x)).series(x, n=4) + + #test for aseries + assert besseli(0,x).series(x, oo, n=4) == sqrt(2)*(sqrt(1/x) - (1/x)**(S(3)/2)/8 - \ + 3*(1/x)**(S(5)/2)/128 - 15*(1/x)**(S(7)/2)/1024 + O((1/x)**(S(9)/2), (x, oo)))*exp(x)/(2*sqrt(pi)) + assert besseli(0,x).series(x,-oo, n=4) == sqrt(2)*(sqrt(-1/x) - (-1/x)**(S(3)/2)/8 - 3*(-1/x)**(S(5)/2)/128 - \ + 15*(-1/x)**(S(7)/2)/1024 + O((-1/x)**(S(9)/2), (x, -oo)))*exp(-x)/(2*sqrt(pi)) + + +def test_besselk_series(): + const = log(2) - S.EulerGamma - log(x) + assert besselk(0, x).series(x, n=4) == const + \ + x**2*(-log(x)/4 - S.EulerGamma/4 + log(2)/4 + S(1)/4) + O(x**4*log(x)) + assert besselk(1, x).series(x, n=4) == 1/x + x*(log(x)/2 - log(2)/2 - \ + S(1)/4 + S.EulerGamma/2) + x**3*(log(x)/16 - S(5)/64 - log(2)/16 + \ + S.EulerGamma/16) + O(x**4*log(x)) + assert besselk(2, x).series(x, n=4) == 2/x**2 - S(1)/2 + x**2*(-log(x)/8 - \ + S.EulerGamma/8 + log(2)/8 + S(3)/32) + O(x**4*log(x)) + assert besselk(2, x).series(x, n=1) == 2/x**2 - S(1)/2 + O(x) #edge case for series truncation + assert besselk(0, x**(1.1)).series(x, n=4) == log(2) - S.EulerGamma - \ + 1.1*log(x) + x**2.2*(-0.275*log(x) - S.EulerGamma/4 + \ + log(2)/4 + S(1)/4) + O(x**4*log(x)) + assert besselk(0, x**2 + x).series(x, n=4) == const + \ + (2 - 2*S.EulerGamma)*(x**3/4 + x**2/8) - x + x**2*(-log(x)/4 + \ + log(2)/4 + S(1)/2) + x**3*(-log(x)/2 - S(7)/12 + log(2)/2) + O(x**4*log(x)) + assert besselk(0, x/(1 - x)).series(x, n=3) == const - x + x**2*(-log(x)/4 - \ + S(1)/4 - S.EulerGamma/4 + log(2)/4) + O(x**3*log(x)) + assert besselk(0, log(1 + x)).series(x, n=3) == const + x/2 + \ + x**2*(-log(x)/4 - S.EulerGamma/4 + S(1)/24 + log(2)/4) + O(x**3*log(x)) + assert besselk(1, 2*sqrt(x)).series(x, n=3) == 1/(2*sqrt(x)) + \ + sqrt(x)*(log(x)/2 - S(1)/2 + S.EulerGamma) + x**(S(3)/2)*(log(x)/4 - S(5)/8 + \ + S.EulerGamma/2) + x**(S(5)/2)*(log(x)/24 - S(5)/36 + S.EulerGamma/12) + O(x**3*log(x)) + assert besselk(-2, sin(x)).series(x, n=4) == besselk(2, sin(x)).series(x, n=4) + assert besselk(2, x**2).series(x, n=2) == 2/x**4 - S(1)/2 + O(x**2) #edge case for series truncation + assert besselk(2, x**2).series(x, n=6) == 2/x**4 - S(1)/2 + x**4*(-log(x)/4 - S.EulerGamma/8 + log(2)/8 + S(3)/32) + O(x**6*log(x)) + assert (x**2*besselk(2, x)).series(x, n=2) == 2 + O(x**2) + + #test for aseries + assert besselk(0,x).series(x, oo, n=4) == sqrt(2)*sqrt(pi)*(sqrt(1/x) + (1/x)**(S(3)/2)/8 - \ + 3*(1/x)**(S(5)/2)/128 + 15*(1/x)**(S(7)/2)/1024 + O((1/x)**(S(9)/2), (x, oo)))*exp(-x)/2 + assert besselk(0,x).series(x, -oo, n=4) == sqrt(2)*sqrt(pi)*(-I*sqrt(-1/x) + I*(-1/x)**(S(3)/2)/8 + \ + 3*I*(-1/x)**(S(5)/2)/128 + 15*I*(-1/x)**(S(7)/2)/1024 + O((-1/x)**(S(9)/2), (x, -oo)))*exp(-x)/2 + + +def test_besselk_frac_order_series(): + assert besselk(S(5)/3, x).series(x, n=2) == 2**(S(2)/3)*gamma(S(5)/3)/x**(S(5)/3) - \ + 3*gamma(S(5)/3)*x**(S(1)/3)/(4*2**(S(1)/3)) + \ + gamma(-S(5)/3)*x**(S(5)/3)/(4*2**(S(2)/3)) + O(x**2) + assert besselk(S(1)/2, x).series(x, n=2) == sqrt(pi/2)/sqrt(x) - \ + sqrt(pi*x/2) + x**(S(3)/2)*sqrt(pi/2)/2 + O(x**2) + assert besselk(S(1)/2, sqrt(x)).series(x, n=2) == sqrt(pi/2)/x**(S(1)/4) - \ + sqrt(pi/2)*x**(S(1)/4) + sqrt(pi/2)*x**(S(3)/4)/2 - \ + sqrt(pi/2)*x**(S(5)/4)/6 + sqrt(pi/2)*x**(S(7)/4)/24 + O(x**2) + assert besselk(S(1)/2, x**2).series(x, n=2) == sqrt(pi/2)/x \ + - sqrt(pi/2)*x + O(x**2) + assert besselk(-S(1)/2, x).series(x) == besselk(S(1)/2, x).series(x) + assert besselk(-S(7)/6, x).series(x) == besselk(S(7)/6, x).series(x) + + +def test_diff(): + assert besselj(n, z).diff(z) == besselj(n - 1, z)/2 - besselj(n + 1, z)/2 + assert bessely(n, z).diff(z) == bessely(n - 1, z)/2 - bessely(n + 1, z)/2 + assert besseli(n, z).diff(z) == besseli(n - 1, z)/2 + besseli(n + 1, z)/2 + assert besselk(n, z).diff(z) == -besselk(n - 1, z)/2 - besselk(n + 1, z)/2 + assert hankel1(n, z).diff(z) == hankel1(n - 1, z)/2 - hankel1(n + 1, z)/2 + assert hankel2(n, z).diff(z) == hankel2(n - 1, z)/2 - hankel2(n + 1, z)/2 + + +def test_rewrite(): + assert besselj(n, z).rewrite(jn) == sqrt(2*z/pi)*jn(n - S.Half, z) + assert bessely(n, z).rewrite(yn) == sqrt(2*z/pi)*yn(n - S.Half, z) + assert besseli(n, z).rewrite(besselj) == \ + exp(-I*n*pi/2)*besselj(n, polar_lift(I)*z) + assert besselj(n, z).rewrite(besseli) == \ + exp(I*n*pi/2)*besseli(n, polar_lift(-I)*z) + + nu = randcplx() + + assert tn(besselj(nu, z), besselj(nu, z).rewrite(besseli), z) + assert tn(besselj(nu, z), besselj(nu, z).rewrite(bessely), z) + + assert tn(besseli(nu, z), besseli(nu, z).rewrite(besselj), z) + assert tn(besseli(nu, z), besseli(nu, z).rewrite(bessely), z) + + assert tn(bessely(nu, z), bessely(nu, z).rewrite(besselj), z) + assert tn(bessely(nu, z), bessely(nu, z).rewrite(besseli), z) + + assert tn(besselk(nu, z), besselk(nu, z).rewrite(besselj), z) + assert tn(besselk(nu, z), besselk(nu, z).rewrite(besseli), z) + assert tn(besselk(nu, z), besselk(nu, z).rewrite(bessely), z) + + # check that a rewrite was triggered, when the order is set to a generic + # symbol 'nu' + assert yn(nu, z) != yn(nu, z).rewrite(jn) + assert hn1(nu, z) != hn1(nu, z).rewrite(jn) + assert hn2(nu, z) != hn2(nu, z).rewrite(jn) + assert jn(nu, z) != jn(nu, z).rewrite(yn) + assert hn1(nu, z) != hn1(nu, z).rewrite(yn) + assert hn2(nu, z) != hn2(nu, z).rewrite(yn) + + # rewriting spherical bessel functions (SBFs) w.r.t. besselj, bessely is + # not allowed if a generic symbol 'nu' is used as the order of the SBFs + # to avoid inconsistencies (the order of bessel[jy] is allowed to be + # complex-valued, whereas SBFs are defined only for integer orders) + order = nu + for f in (besselj, bessely): + assert hn1(order, z) == hn1(order, z).rewrite(f) + assert hn2(order, z) == hn2(order, z).rewrite(f) + + assert jn(order, z).rewrite(besselj) == sqrt(2)*sqrt(pi)*sqrt(1/z)*besselj(order + S.Half, z)/2 + assert jn(order, z).rewrite(bessely) == (-1)**nu*sqrt(2)*sqrt(pi)*sqrt(1/z)*bessely(-order - S.Half, z)/2 + + # for integral orders rewriting SBFs w.r.t bessel[jy] is allowed + N = Symbol('n', integer=True) + ri = randint(-11, 10) + for order in (ri, N): + for f in (besselj, bessely): + assert yn(order, z) != yn(order, z).rewrite(f) + assert jn(order, z) != jn(order, z).rewrite(f) + assert hn1(order, z) != hn1(order, z).rewrite(f) + assert hn2(order, z) != hn2(order, z).rewrite(f) + + for func, refunc in product((yn, jn, hn1, hn2), + (jn, yn, besselj, bessely)): + assert tn(func(ri, z), func(ri, z).rewrite(refunc), z) + + +def test_expand(): + assert expand_func(besselj(S.Half, z).rewrite(jn)) == \ + sqrt(2)*sin(z)/(sqrt(pi)*sqrt(z)) + assert expand_func(bessely(S.Half, z).rewrite(yn)) == \ + -sqrt(2)*cos(z)/(sqrt(pi)*sqrt(z)) + + # XXX: teach sin/cos to work around arguments like + # x*exp_polar(I*pi*n/2). Then change besselsimp -> expand_func + assert besselsimp(besselj(S.Half, z)) == sqrt(2)*sin(z)/(sqrt(pi)*sqrt(z)) + assert besselsimp(besselj(Rational(-1, 2), z)) == sqrt(2)*cos(z)/(sqrt(pi)*sqrt(z)) + assert besselsimp(besselj(Rational(5, 2), z)) == \ + -sqrt(2)*(z**2*sin(z) + 3*z*cos(z) - 3*sin(z))/(sqrt(pi)*z**Rational(5, 2)) + assert besselsimp(besselj(Rational(-5, 2), z)) == \ + -sqrt(2)*(z**2*cos(z) - 3*z*sin(z) - 3*cos(z))/(sqrt(pi)*z**Rational(5, 2)) + + assert besselsimp(bessely(S.Half, z)) == \ + -(sqrt(2)*cos(z))/(sqrt(pi)*sqrt(z)) + assert besselsimp(bessely(Rational(-1, 2), z)) == sqrt(2)*sin(z)/(sqrt(pi)*sqrt(z)) + assert besselsimp(bessely(Rational(5, 2), z)) == \ + sqrt(2)*(z**2*cos(z) - 3*z*sin(z) - 3*cos(z))/(sqrt(pi)*z**Rational(5, 2)) + assert besselsimp(bessely(Rational(-5, 2), z)) == \ + -sqrt(2)*(z**2*sin(z) + 3*z*cos(z) - 3*sin(z))/(sqrt(pi)*z**Rational(5, 2)) + + assert besselsimp(besseli(S.Half, z)) == sqrt(2)*sinh(z)/(sqrt(pi)*sqrt(z)) + assert besselsimp(besseli(Rational(-1, 2), z)) == \ + sqrt(2)*cosh(z)/(sqrt(pi)*sqrt(z)) + assert besselsimp(besseli(Rational(5, 2), z)) == \ + sqrt(2)*(z**2*sinh(z) - 3*z*cosh(z) + 3*sinh(z))/(sqrt(pi)*z**Rational(5, 2)) + assert besselsimp(besseli(Rational(-5, 2), z)) == \ + sqrt(2)*(z**2*cosh(z) - 3*z*sinh(z) + 3*cosh(z))/(sqrt(pi)*z**Rational(5, 2)) + + assert besselsimp(besselk(S.Half, z)) == \ + besselsimp(besselk(Rational(-1, 2), z)) == sqrt(pi)*exp(-z)/(sqrt(2)*sqrt(z)) + assert besselsimp(besselk(Rational(5, 2), z)) == \ + besselsimp(besselk(Rational(-5, 2), z)) == \ + sqrt(2)*sqrt(pi)*(z**2 + 3*z + 3)*exp(-z)/(2*z**Rational(5, 2)) + + n = Symbol('n', integer=True, positive=True) + + assert expand_func(besseli(n + 2, z)) == \ + besseli(n, z) + (-2*n - 2)*(-2*n*besseli(n, z)/z + besseli(n - 1, z))/z + assert expand_func(besselj(n + 2, z)) == \ + -besselj(n, z) + (2*n + 2)*(2*n*besselj(n, z)/z - besselj(n - 1, z))/z + assert expand_func(besselk(n + 2, z)) == \ + besselk(n, z) + (2*n + 2)*(2*n*besselk(n, z)/z + besselk(n - 1, z))/z + assert expand_func(bessely(n + 2, z)) == \ + -bessely(n, z) + (2*n + 2)*(2*n*bessely(n, z)/z - bessely(n - 1, z))/z + + assert expand_func(besseli(n + S.Half, z).rewrite(jn)) == \ + (sqrt(2)*sqrt(z)*exp(-I*pi*(n + S.Half)/2) * + exp_polar(I*pi/4)*jn(n, z*exp_polar(I*pi/2))/sqrt(pi)) + assert expand_func(besselj(n + S.Half, z).rewrite(jn)) == \ + sqrt(2)*sqrt(z)*jn(n, z)/sqrt(pi) + + r = Symbol('r', real=True) + p = Symbol('p', positive=True) + i = Symbol('i', integer=True) + + for besselx in [besselj, bessely, besseli, besselk]: + assert besselx(i, p).is_extended_real is True + assert besselx(i, x).is_extended_real is None + assert besselx(x, z).is_extended_real is None + + for besselx in [besselj, besseli]: + assert besselx(i, r).is_extended_real is True + for besselx in [bessely, besselk]: + assert besselx(i, r).is_extended_real is None + + for besselx in [besselj, bessely, besseli, besselk]: + assert expand_func(besselx(oo, x)) == besselx(oo, x, evaluate=False) + assert expand_func(besselx(-oo, x)) == besselx(-oo, x, evaluate=False) + + +# Quite varying time, but often really slow +@slow +def test_slow_expand(): + def check(eq, ans): + return tn(eq, ans) and eq == ans + + rn = randcplx(a=1, b=0, d=0, c=2) + + for besselx in [besselj, bessely, besseli, besselk]: + ri = S(2*randint(-11, 10) + 1) / 2 # half integer in [-21/2, 21/2] + assert tn(besselsimp(besselx(ri, z)), besselx(ri, z)) + + assert check(expand_func(besseli(rn, x)), + besseli(rn - 2, x) - 2*(rn - 1)*besseli(rn - 1, x)/x) + assert check(expand_func(besseli(-rn, x)), + besseli(-rn + 2, x) + 2*(-rn + 1)*besseli(-rn + 1, x)/x) + + assert check(expand_func(besselj(rn, x)), + -besselj(rn - 2, x) + 2*(rn - 1)*besselj(rn - 1, x)/x) + assert check(expand_func(besselj(-rn, x)), + -besselj(-rn + 2, x) + 2*(-rn + 1)*besselj(-rn + 1, x)/x) + + assert check(expand_func(besselk(rn, x)), + besselk(rn - 2, x) + 2*(rn - 1)*besselk(rn - 1, x)/x) + assert check(expand_func(besselk(-rn, x)), + besselk(-rn + 2, x) - 2*(-rn + 1)*besselk(-rn + 1, x)/x) + + assert check(expand_func(bessely(rn, x)), + -bessely(rn - 2, x) + 2*(rn - 1)*bessely(rn - 1, x)/x) + assert check(expand_func(bessely(-rn, x)), + -bessely(-rn + 2, x) + 2*(-rn + 1)*bessely(-rn + 1, x)/x) + + +def mjn(n, z): + return expand_func(jn(n, z)) + + +def myn(n, z): + return expand_func(yn(n, z)) + + +def test_jn(): + z = symbols("z") + assert jn(0, 0) == 1 + assert jn(1, 0) == 0 + assert jn(-1, 0) == S.ComplexInfinity + assert jn(z, 0) == jn(z, 0, evaluate=False) + assert jn(0, oo) == 0 + assert jn(0, -oo) == 0 + + assert mjn(0, z) == sin(z)/z + assert mjn(1, z) == sin(z)/z**2 - cos(z)/z + assert mjn(2, z) == (3/z**3 - 1/z)*sin(z) - (3/z**2) * cos(z) + assert mjn(3, z) == (15/z**4 - 6/z**2)*sin(z) + (1/z - 15/z**3)*cos(z) + assert mjn(4, z) == (1/z + 105/z**5 - 45/z**3)*sin(z) + \ + (-105/z**4 + 10/z**2)*cos(z) + assert mjn(5, z) == (945/z**6 - 420/z**4 + 15/z**2)*sin(z) + \ + (-1/z - 945/z**5 + 105/z**3)*cos(z) + assert mjn(6, z) == (-1/z + 10395/z**7 - 4725/z**5 + 210/z**3)*sin(z) + \ + (-10395/z**6 + 1260/z**4 - 21/z**2)*cos(z) + + assert expand_func(jn(n, z)) == jn(n, z) + + # SBFs not defined for complex-valued orders + assert jn(2+3j, 5.2+0.3j).evalf() == jn(2+3j, 5.2+0.3j) + + assert eq([jn(2, 5.2+0.3j).evalf(10)], + [0.09941975672 - 0.05452508024*I]) + + +def test_yn(): + z = symbols("z") + assert myn(0, z) == -cos(z)/z + assert myn(1, z) == -cos(z)/z**2 - sin(z)/z + assert myn(2, z) == -((3/z**3 - 1/z)*cos(z) + (3/z**2)*sin(z)) + assert expand_func(yn(n, z)) == yn(n, z) + + # SBFs not defined for complex-valued orders + assert yn(2+3j, 5.2+0.3j).evalf() == yn(2+3j, 5.2+0.3j) + + assert eq([yn(2, 5.2+0.3j).evalf(10)], + [0.185250342 + 0.01489557397*I]) + + +def test_sympify_yn(): + assert S(15) in myn(3, pi).atoms() + assert myn(3, pi) == 15/pi**4 - 6/pi**2 + + +def eq(a, b, tol=1e-6): + for u, v in zip(a, b): + if not (abs(u - v) < tol): + return False + return True + + +def test_jn_zeros(): + assert eq(jn_zeros(0, 4), [3.141592, 6.283185, 9.424777, 12.566370]) + assert eq(jn_zeros(1, 4), [4.493409, 7.725251, 10.904121, 14.066193]) + assert eq(jn_zeros(2, 4), [5.763459, 9.095011, 12.322940, 15.514603]) + assert eq(jn_zeros(3, 4), [6.987932, 10.417118, 13.698023, 16.923621]) + assert eq(jn_zeros(4, 4), [8.182561, 11.704907, 15.039664, 18.301255]) + + +def test_bessel_eval(): + n, m, k = Symbol('n', integer=True), Symbol('m'), Symbol('k', integer=True, zero=False) + + for f in [besselj, besseli]: + assert f(0, 0) is S.One + assert f(2.1, 0) is S.Zero + assert f(-3, 0) is S.Zero + assert f(-10.2, 0) is S.ComplexInfinity + assert f(1 + 3*I, 0) is S.Zero + assert f(-3 + I, 0) is S.ComplexInfinity + assert f(-2*I, 0) is S.NaN + assert f(n, 0) != S.One and f(n, 0) != S.Zero + assert f(m, 0) != S.One and f(m, 0) != S.Zero + assert f(k, 0) is S.Zero + + assert bessely(0, 0) is S.NegativeInfinity + assert besselk(0, 0) is S.Infinity + for f in [bessely, besselk]: + assert f(1 + I, 0) is S.ComplexInfinity + assert f(I, 0) is S.NaN + + for f in [besselj, bessely]: + assert f(m, S.Infinity) is S.Zero + assert f(m, S.NegativeInfinity) is S.Zero + + for f in [besseli, besselk]: + assert f(m, I*S.Infinity) is S.Zero + assert f(m, I*S.NegativeInfinity) is S.Zero + + for f in [besseli, besselk]: + assert f(-4, z) == f(4, z) + assert f(-3, z) == f(3, z) + assert f(-n, z) == f(n, z) + assert f(-m, z) != f(m, z) + + for f in [besselj, bessely]: + assert f(-4, z) == f(4, z) + assert f(-3, z) == -f(3, z) + assert f(-n, z) == (-1)**n*f(n, z) + assert f(-m, z) != (-1)**m*f(m, z) + + for f in [besselj, besseli]: + assert f(m, -z) == (-z)**m*z**(-m)*f(m, z) + + assert besseli(2, -z) == besseli(2, z) + assert besseli(3, -z) == -besseli(3, z) + + assert besselj(0, -z) == besselj(0, z) + assert besselj(1, -z) == -besselj(1, z) + + assert besseli(0, I*z) == besselj(0, z) + assert besseli(1, I*z) == I*besselj(1, z) + assert besselj(3, I*z) == -I*besseli(3, z) + + +def test_bessel_nan(): + # FIXME: could have these return NaN; for now just fix infinite recursion + for f in [besselj, bessely, besseli, besselk, hankel1, hankel2, yn, jn]: + assert f(1, S.NaN) == f(1, S.NaN, evaluate=False) + + +def test_meromorphic(): + assert besselj(2, x).is_meromorphic(x, 1) == True + assert besselj(2, x).is_meromorphic(x, 0) == True + assert besselj(2, x).is_meromorphic(x, oo) == False + assert besselj(S(2)/3, x).is_meromorphic(x, 1) == True + assert besselj(S(2)/3, x).is_meromorphic(x, 0) == False + assert besselj(S(2)/3, x).is_meromorphic(x, oo) == False + assert besselj(x, 2*x).is_meromorphic(x, 2) == False + assert besselk(0, x).is_meromorphic(x, 1) == True + assert besselk(2, x).is_meromorphic(x, 0) == True + assert besseli(0, x).is_meromorphic(x, 1) == True + assert besseli(2, x).is_meromorphic(x, 0) == True + assert bessely(0, x).is_meromorphic(x, 1) == True + assert bessely(0, x).is_meromorphic(x, 0) == False + assert bessely(2, x).is_meromorphic(x, 0) == True + assert hankel1(3, x**2 + 2*x).is_meromorphic(x, 1) == True + assert hankel1(0, x).is_meromorphic(x, 0) == False + assert hankel2(11, 4).is_meromorphic(x, 5) == True + assert hn1(6, 7*x**3 + 4).is_meromorphic(x, 7) == True + assert hn2(3, 2*x).is_meromorphic(x, 9) == True + assert jn(5, 2*x + 7).is_meromorphic(x, 4) == True + assert yn(8, x**2 + 11).is_meromorphic(x, 6) == True + + +def test_conjugate(): + n = Symbol('n') + z = Symbol('z', extended_real=False) + x = Symbol('x', extended_real=True) + y = Symbol('y', positive=True) + t = Symbol('t', negative=True) + + for f in [besseli, besselj, besselk, bessely, hankel1, hankel2]: + assert f(n, -1).conjugate() != f(conjugate(n), -1) + assert f(n, x).conjugate() != f(conjugate(n), x) + assert f(n, t).conjugate() != f(conjugate(n), t) + + rz = randcplx(b=0.5) + + for f in [besseli, besselj, besselk, bessely]: + assert f(n, 1 + I).conjugate() == f(conjugate(n), 1 - I) + assert f(n, 0).conjugate() == f(conjugate(n), 0) + assert f(n, 1).conjugate() == f(conjugate(n), 1) + assert f(n, z).conjugate() == f(conjugate(n), conjugate(z)) + assert f(n, y).conjugate() == f(conjugate(n), y) + assert tn(f(n, rz).conjugate(), f(conjugate(n), conjugate(rz))) + + assert hankel1(n, 1 + I).conjugate() == hankel2(conjugate(n), 1 - I) + assert hankel1(n, 0).conjugate() == hankel2(conjugate(n), 0) + assert hankel1(n, 1).conjugate() == hankel2(conjugate(n), 1) + assert hankel1(n, y).conjugate() == hankel2(conjugate(n), y) + assert hankel1(n, z).conjugate() == hankel2(conjugate(n), conjugate(z)) + assert tn(hankel1(n, rz).conjugate(), hankel2(conjugate(n), conjugate(rz))) + + assert hankel2(n, 1 + I).conjugate() == hankel1(conjugate(n), 1 - I) + assert hankel2(n, 0).conjugate() == hankel1(conjugate(n), 0) + assert hankel2(n, 1).conjugate() == hankel1(conjugate(n), 1) + assert hankel2(n, y).conjugate() == hankel1(conjugate(n), y) + assert hankel2(n, z).conjugate() == hankel1(conjugate(n), conjugate(z)) + assert tn(hankel2(n, rz).conjugate(), hankel1(conjugate(n), conjugate(rz))) + + +def test_branching(): + assert besselj(polar_lift(k), x) == besselj(k, x) + assert besseli(polar_lift(k), x) == besseli(k, x) + + n = Symbol('n', integer=True) + assert besselj(n, exp_polar(2*pi*I)*x) == besselj(n, x) + assert besselj(n, polar_lift(x)) == besselj(n, x) + assert besseli(n, exp_polar(2*pi*I)*x) == besseli(n, x) + assert besseli(n, polar_lift(x)) == besseli(n, x) + + def tn(func, s): + from sympy.core.random import uniform + c = uniform(1, 5) + expr = func(s, c*exp_polar(I*pi)) - func(s, c*exp_polar(-I*pi)) + eps = 1e-15 + expr2 = func(s + eps, -c + eps*I) - func(s + eps, -c - eps*I) + return abs(expr.n() - expr2.n()).n() < 1e-10 + + nu = Symbol('nu') + assert besselj(nu, exp_polar(2*pi*I)*x) == exp(2*pi*I*nu)*besselj(nu, x) + assert besseli(nu, exp_polar(2*pi*I)*x) == exp(2*pi*I*nu)*besseli(nu, x) + assert tn(besselj, 2) + assert tn(besselj, pi) + assert tn(besselj, I) + assert tn(besseli, 2) + assert tn(besseli, pi) + assert tn(besseli, I) + + +def test_airy_base(): + z = Symbol('z') + x = Symbol('x', real=True) + y = Symbol('y', real=True) + + assert conjugate(airyai(z)) == airyai(conjugate(z)) + assert airyai(x).is_extended_real + + assert airyai(x+I*y).as_real_imag() == ( + airyai(x - I*y)/2 + airyai(x + I*y)/2, + I*(airyai(x - I*y) - airyai(x + I*y))/2) + + +def test_airyai(): + z = Symbol('z', real=False) + t = Symbol('t', negative=True) + p = Symbol('p', positive=True) + + assert isinstance(airyai(z), airyai) + + assert airyai(0) == 3**Rational(1, 3)/(3*gamma(Rational(2, 3))) + assert airyai(oo) == 0 + assert airyai(-oo) == 0 + + assert diff(airyai(z), z) == airyaiprime(z) + + assert series(airyai(z), z, 0, 3) == ( + 3**Rational(5, 6)*gamma(Rational(1, 3))/(6*pi) - 3**Rational(1, 6)*z*gamma(Rational(2, 3))/(2*pi) + O(z**3)) + + assert airyai(z).rewrite(hyper) == ( + -3**Rational(2, 3)*z*hyper((), (Rational(4, 3),), z**3/9)/(3*gamma(Rational(1, 3))) + + 3**Rational(1, 3)*hyper((), (Rational(2, 3),), z**3/9)/(3*gamma(Rational(2, 3)))) + + assert isinstance(airyai(z).rewrite(besselj), airyai) + assert airyai(t).rewrite(besselj) == ( + sqrt(-t)*(besselj(Rational(-1, 3), 2*(-t)**Rational(3, 2)/3) + + besselj(Rational(1, 3), 2*(-t)**Rational(3, 2)/3))/3) + assert airyai(z).rewrite(besseli) == ( + -z*besseli(Rational(1, 3), 2*z**Rational(3, 2)/3)/(3*(z**Rational(3, 2))**Rational(1, 3)) + + (z**Rational(3, 2))**Rational(1, 3)*besseli(Rational(-1, 3), 2*z**Rational(3, 2)/3)/3) + assert airyai(p).rewrite(besseli) == ( + sqrt(p)*(besseli(Rational(-1, 3), 2*p**Rational(3, 2)/3) - + besseli(Rational(1, 3), 2*p**Rational(3, 2)/3))/3) + + assert expand_func(airyai(2*(3*z**5)**Rational(1, 3))) == ( + -sqrt(3)*(-1 + (z**5)**Rational(1, 3)/z**Rational(5, 3))*airybi(2*3**Rational(1, 3)*z**Rational(5, 3))/6 + + (1 + (z**5)**Rational(1, 3)/z**Rational(5, 3))*airyai(2*3**Rational(1, 3)*z**Rational(5, 3))/2) + + +def test_airybi(): + z = Symbol('z', real=False) + t = Symbol('t', negative=True) + p = Symbol('p', positive=True) + + assert isinstance(airybi(z), airybi) + + assert airybi(0) == 3**Rational(5, 6)/(3*gamma(Rational(2, 3))) + assert airybi(oo) is oo + assert airybi(-oo) == 0 + + assert diff(airybi(z), z) == airybiprime(z) + + assert series(airybi(z), z, 0, 3) == ( + 3**Rational(1, 3)*gamma(Rational(1, 3))/(2*pi) + 3**Rational(2, 3)*z*gamma(Rational(2, 3))/(2*pi) + O(z**3)) + + assert airybi(z).rewrite(hyper) == ( + 3**Rational(1, 6)*z*hyper((), (Rational(4, 3),), z**3/9)/gamma(Rational(1, 3)) + + 3**Rational(5, 6)*hyper((), (Rational(2, 3),), z**3/9)/(3*gamma(Rational(2, 3)))) + + assert isinstance(airybi(z).rewrite(besselj), airybi) + assert airyai(t).rewrite(besselj) == ( + sqrt(-t)*(besselj(Rational(-1, 3), 2*(-t)**Rational(3, 2)/3) + + besselj(Rational(1, 3), 2*(-t)**Rational(3, 2)/3))/3) + assert airybi(z).rewrite(besseli) == ( + sqrt(3)*(z*besseli(Rational(1, 3), 2*z**Rational(3, 2)/3)/(z**Rational(3, 2))**Rational(1, 3) + + (z**Rational(3, 2))**Rational(1, 3)*besseli(Rational(-1, 3), 2*z**Rational(3, 2)/3))/3) + assert airybi(p).rewrite(besseli) == ( + sqrt(3)*sqrt(p)*(besseli(Rational(-1, 3), 2*p**Rational(3, 2)/3) + + besseli(Rational(1, 3), 2*p**Rational(3, 2)/3))/3) + + assert expand_func(airybi(2*(3*z**5)**Rational(1, 3))) == ( + sqrt(3)*(1 - (z**5)**Rational(1, 3)/z**Rational(5, 3))*airyai(2*3**Rational(1, 3)*z**Rational(5, 3))/2 + + (1 + (z**5)**Rational(1, 3)/z**Rational(5, 3))*airybi(2*3**Rational(1, 3)*z**Rational(5, 3))/2) + + +def test_airyaiprime(): + z = Symbol('z', real=False) + t = Symbol('t', negative=True) + p = Symbol('p', positive=True) + + assert isinstance(airyaiprime(z), airyaiprime) + + assert airyaiprime(0) == -3**Rational(2, 3)/(3*gamma(Rational(1, 3))) + assert airyaiprime(oo) == 0 + + assert diff(airyaiprime(z), z) == z*airyai(z) + + assert series(airyaiprime(z), z, 0, 3) == ( + -3**Rational(2, 3)/(3*gamma(Rational(1, 3))) + 3**Rational(1, 3)*z**2/(6*gamma(Rational(2, 3))) + O(z**3)) + + assert airyaiprime(z).rewrite(hyper) == ( + 3**Rational(1, 3)*z**2*hyper((), (Rational(5, 3),), z**3/9)/(6*gamma(Rational(2, 3))) - + 3**Rational(2, 3)*hyper((), (Rational(1, 3),), z**3/9)/(3*gamma(Rational(1, 3)))) + + assert isinstance(airyaiprime(z).rewrite(besselj), airyaiprime) + assert airyai(t).rewrite(besselj) == ( + sqrt(-t)*(besselj(Rational(-1, 3), 2*(-t)**Rational(3, 2)/3) + + besselj(Rational(1, 3), 2*(-t)**Rational(3, 2)/3))/3) + assert airyaiprime(z).rewrite(besseli) == ( + z**2*besseli(Rational(2, 3), 2*z**Rational(3, 2)/3)/(3*(z**Rational(3, 2))**Rational(2, 3)) - + (z**Rational(3, 2))**Rational(2, 3)*besseli(Rational(-1, 3), 2*z**Rational(3, 2)/3)/3) + assert airyaiprime(p).rewrite(besseli) == ( + p*(-besseli(Rational(-2, 3), 2*p**Rational(3, 2)/3) + besseli(Rational(2, 3), 2*p**Rational(3, 2)/3))/3) + + assert expand_func(airyaiprime(2*(3*z**5)**Rational(1, 3))) == ( + sqrt(3)*(z**Rational(5, 3)/(z**5)**Rational(1, 3) - 1)*airybiprime(2*3**Rational(1, 3)*z**Rational(5, 3))/6 + + (z**Rational(5, 3)/(z**5)**Rational(1, 3) + 1)*airyaiprime(2*3**Rational(1, 3)*z**Rational(5, 3))/2) + + +def test_airybiprime(): + z = Symbol('z', real=False) + t = Symbol('t', negative=True) + p = Symbol('p', positive=True) + + assert isinstance(airybiprime(z), airybiprime) + + assert airybiprime(0) == 3**Rational(1, 6)/gamma(Rational(1, 3)) + assert airybiprime(oo) is oo + assert airybiprime(-oo) == 0 + + assert diff(airybiprime(z), z) == z*airybi(z) + + assert series(airybiprime(z), z, 0, 3) == ( + 3**Rational(1, 6)/gamma(Rational(1, 3)) + 3**Rational(5, 6)*z**2/(6*gamma(Rational(2, 3))) + O(z**3)) + + assert airybiprime(z).rewrite(hyper) == ( + 3**Rational(5, 6)*z**2*hyper((), (Rational(5, 3),), z**3/9)/(6*gamma(Rational(2, 3))) + + 3**Rational(1, 6)*hyper((), (Rational(1, 3),), z**3/9)/gamma(Rational(1, 3))) + + assert isinstance(airybiprime(z).rewrite(besselj), airybiprime) + assert airyai(t).rewrite(besselj) == ( + sqrt(-t)*(besselj(Rational(-1, 3), 2*(-t)**Rational(3, 2)/3) + + besselj(Rational(1, 3), 2*(-t)**Rational(3, 2)/3))/3) + assert airybiprime(z).rewrite(besseli) == ( + sqrt(3)*(z**2*besseli(Rational(2, 3), 2*z**Rational(3, 2)/3)/(z**Rational(3, 2))**Rational(2, 3) + + (z**Rational(3, 2))**Rational(2, 3)*besseli(Rational(-2, 3), 2*z**Rational(3, 2)/3))/3) + assert airybiprime(p).rewrite(besseli) == ( + sqrt(3)*p*(besseli(Rational(-2, 3), 2*p**Rational(3, 2)/3) + besseli(Rational(2, 3), 2*p**Rational(3, 2)/3))/3) + + assert expand_func(airybiprime(2*(3*z**5)**Rational(1, 3))) == ( + sqrt(3)*(z**Rational(5, 3)/(z**5)**Rational(1, 3) - 1)*airyaiprime(2*3**Rational(1, 3)*z**Rational(5, 3))/2 + + (z**Rational(5, 3)/(z**5)**Rational(1, 3) + 1)*airybiprime(2*3**Rational(1, 3)*z**Rational(5, 3))/2) + + +def test_marcumq(): + m = Symbol('m') + a = Symbol('a') + b = Symbol('b') + + assert marcumq(0, 0, 0) == 0 + assert marcumq(m, 0, b) == uppergamma(m, b**2/2)/gamma(m) + assert marcumq(2, 0, 5) == 27*exp(Rational(-25, 2))/2 + assert marcumq(0, a, 0) == 1 - exp(-a**2/2) + assert marcumq(0, pi, 0) == 1 - exp(-pi**2/2) + assert marcumq(1, a, a) == S.Half + exp(-a**2)*besseli(0, a**2)/2 + assert marcumq(2, a, a) == S.Half + exp(-a**2)*besseli(0, a**2)/2 + exp(-a**2)*besseli(1, a**2) + + assert diff(marcumq(1, a, 3), a) == a*(-marcumq(1, a, 3) + marcumq(2, a, 3)) + assert diff(marcumq(2, 3, b), b) == -b**2*exp(-b**2/2 - Rational(9, 2))*besseli(1, 3*b)/3 + + x = Symbol('x') + assert marcumq(2, 3, 4).rewrite(Integral, x=x) == \ + Integral(x**2*exp(-x**2/2 - Rational(9, 2))*besseli(1, 3*x), (x, 4, oo))/3 + assert eq([marcumq(5, -2, 3).rewrite(Integral).evalf(10)], + [0.7905769565]) + + k = Symbol('k') + assert marcumq(-3, -5, -7).rewrite(Sum, k=k) == \ + exp(-37)*Sum((Rational(5, 7))**k*besseli(k, 35), (k, 4, oo)) + assert eq([marcumq(1, 3, 1).rewrite(Sum).evalf(10)], + [0.9891705502]) + + assert marcumq(1, a, a, evaluate=False).rewrite(besseli) == S.Half + exp(-a**2)*besseli(0, a**2)/2 + assert marcumq(2, a, a, evaluate=False).rewrite(besseli) == S.Half + exp(-a**2)*besseli(0, a**2)/2 + \ + exp(-a**2)*besseli(1, a**2) + assert marcumq(3, a, a).rewrite(besseli) == (besseli(1, a**2) + besseli(2, a**2))*exp(-a**2) + \ + S.Half + exp(-a**2)*besseli(0, a**2)/2 + assert marcumq(5, 8, 8).rewrite(besseli) == exp(-64)*besseli(0, 64)/2 + \ + (besseli(4, 64) + besseli(3, 64) + besseli(2, 64) + besseli(1, 64))*exp(-64) + S.Half + assert marcumq(m, a, a).rewrite(besseli) == marcumq(m, a, a) + + x = Symbol('x', integer=True) + assert marcumq(x, a, a).rewrite(besseli) == marcumq(x, a, a) + + +def test_issue_26134(): + x = Symbol('x') + assert marcumq(2, 3, 4).rewrite(Integral, x=x).dummy_eq( + Integral(x**2*exp(-x**2/2 - Rational(9, 2))*besseli(1, 3*x), (x, 4, oo))/3) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_beta_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_beta_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..b34cb2febf9e2746d869cd878525d2794535aea5 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_beta_functions.py @@ -0,0 +1,89 @@ +from sympy.core.function import (diff, expand_func) +from sympy.core.numbers import I, Rational, pi +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, symbols) +from sympy.functions.combinatorial.numbers import catalan +from sympy.functions.elementary.complexes import conjugate +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.special.beta_functions import (beta, betainc, betainc_regularized) +from sympy.functions.special.gamma_functions import gamma, polygamma +from sympy.functions.special.hyper import hyper +from sympy.integrals.integrals import Integral +from sympy.core.function import ArgumentIndexError +from sympy.core.expr import unchanged +from sympy.testing.pytest import raises + + +def test_beta(): + x, y = symbols('x y') + t = Dummy('t') + + assert unchanged(beta, x, y) + assert unchanged(beta, x, x) + + assert beta(5, -3).is_real == True + assert beta(3, y).is_real is None + + assert expand_func(beta(x, y)) == gamma(x)*gamma(y)/gamma(x + y) + assert expand_func(beta(x, y) - beta(y, x)) == 0 # Symmetric + assert expand_func(beta(x, y)) == expand_func(beta(x, y + 1) + beta(x + 1, y)).simplify() + + assert diff(beta(x, y), x) == beta(x, y)*(polygamma(0, x) - polygamma(0, x + y)) + assert diff(beta(x, y), y) == beta(x, y)*(polygamma(0, y) - polygamma(0, x + y)) + + assert conjugate(beta(x, y)) == beta(conjugate(x), conjugate(y)) + + raises(ArgumentIndexError, lambda: beta(x, y).fdiff(3)) + + assert beta(x, y).rewrite(gamma) == gamma(x)*gamma(y)/gamma(x + y) + assert beta(x).rewrite(gamma) == gamma(x)**2/gamma(2*x) + assert beta(x, y).rewrite(Integral).dummy_eq(Integral(t**(x - 1) * (1 - t)**(y - 1), (t, 0, 1))) + assert beta(Rational(-19, 10), Rational(-1, 10)) == S.Zero + assert beta(Rational(-19, 10), Rational(-9, 10)) == \ + 800*2**(S(4)/5)*sqrt(pi)*gamma(S.One/10)/(171*gamma(-S(7)/5)) + assert beta(Rational(19, 10), Rational(29, 10)) == 100/(551*catalan(Rational(19, 10))) + assert beta(1, 0) == S.ComplexInfinity + assert beta(0, 1) == S.ComplexInfinity + assert beta(2, 3) == S.One/12 + assert unchanged(beta, x, x + 1) + assert unchanged(beta, x, 1) + assert unchanged(beta, 1, y) + assert beta(x, x + 1).doit() == 1/(x*(x+1)*catalan(x)) + assert beta(1, y).doit() == 1/y + assert beta(x, 1).doit() == 1/x + assert beta(Rational(-19, 10), Rational(-1, 10), evaluate=False).doit() == S.Zero + assert beta(2) == beta(2, 2) + assert beta(x, evaluate=False) != beta(x, x) + assert beta(x, evaluate=False).doit() == beta(x, x) + + +def test_betainc(): + a, b, x1, x2 = symbols('a b x1 x2') + + assert unchanged(betainc, a, b, x1, x2) + assert unchanged(betainc, a, b, 0, x1) + + assert betainc(1, 2, 0, -5).is_real == True + assert betainc(1, 2, 0, x2).is_real is None + assert conjugate(betainc(I, 2, 3 - I, 1 + 4*I)) == betainc(-I, 2, 3 + I, 1 - 4*I) + + assert betainc(a, b, 0, 1).rewrite(Integral).dummy_eq(beta(a, b).rewrite(Integral)) + assert betainc(1, 2, 0, x2).rewrite(hyper) == x2*hyper((1, -1), (2,), x2) + + assert betainc(1, 2, 3, 3).evalf() == 0 + + +def test_betainc_regularized(): + a, b, x1, x2 = symbols('a b x1 x2') + + assert unchanged(betainc_regularized, a, b, x1, x2) + assert unchanged(betainc_regularized, a, b, 0, x1) + + assert betainc_regularized(3, 5, 0, -1).is_real == True + assert betainc_regularized(3, 5, 0, x2).is_real is None + assert conjugate(betainc_regularized(3*I, 1, 2 + I, 1 + 2*I)) == betainc_regularized(-3*I, 1, 2 - I, 1 - 2*I) + + assert betainc_regularized(a, b, 0, 1).rewrite(Integral) == 1 + assert betainc_regularized(1, 2, x1, x2).rewrite(hyper) == 2*x2*hyper((1, -1), (2,), x2) - 2*x1*hyper((1, -1), (2,), x1) + + assert betainc_regularized(4, 1, 5, 5).evalf() == 0 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_bsplines.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_bsplines.py new file mode 100644 index 0000000000000000000000000000000000000000..136831b96ba16c95edba12ecd47b6f1566b68427 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_bsplines.py @@ -0,0 +1,167 @@ +from sympy.functions import bspline_basis_set, interpolating_spline +from sympy.core.numbers import Rational +from sympy.core.singleton import S +from sympy.core.symbol import symbols +from sympy.functions.elementary.piecewise import Piecewise +from sympy.logic.boolalg import And +from sympy.sets.sets import Interval +from sympy.testing.pytest import slow + +x, y = symbols('x,y') + + +def test_basic_degree_0(): + d = 0 + knots = range(5) + splines = bspline_basis_set(d, knots, x) + for i in range(len(splines)): + assert splines[i] == Piecewise((1, Interval(i, i + 1).contains(x)), + (0, True)) + + +def test_basic_degree_1(): + d = 1 + knots = range(5) + splines = bspline_basis_set(d, knots, x) + assert splines[0] == Piecewise((x, Interval(0, 1).contains(x)), + (2 - x, Interval(1, 2).contains(x)), + (0, True)) + assert splines[1] == Piecewise((-1 + x, Interval(1, 2).contains(x)), + (3 - x, Interval(2, 3).contains(x)), + (0, True)) + assert splines[2] == Piecewise((-2 + x, Interval(2, 3).contains(x)), + (4 - x, Interval(3, 4).contains(x)), + (0, True)) + + +def test_basic_degree_2(): + d = 2 + knots = range(5) + splines = bspline_basis_set(d, knots, x) + b0 = Piecewise((x**2/2, Interval(0, 1).contains(x)), + (Rational(-3, 2) + 3*x - x**2, Interval(1, 2).contains(x)), + (Rational(9, 2) - 3*x + x**2/2, Interval(2, 3).contains(x)), + (0, True)) + b1 = Piecewise((S.Half - x + x**2/2, Interval(1, 2).contains(x)), + (Rational(-11, 2) + 5*x - x**2, Interval(2, 3).contains(x)), + (8 - 4*x + x**2/2, Interval(3, 4).contains(x)), + (0, True)) + assert splines[0] == b0 + assert splines[1] == b1 + + +def test_basic_degree_3(): + d = 3 + knots = range(5) + splines = bspline_basis_set(d, knots, x) + b0 = Piecewise( + (x**3/6, Interval(0, 1).contains(x)), + (Rational(2, 3) - 2*x + 2*x**2 - x**3/2, Interval(1, 2).contains(x)), + (Rational(-22, 3) + 10*x - 4*x**2 + x**3/2, Interval(2, 3).contains(x)), + (Rational(32, 3) - 8*x + 2*x**2 - x**3/6, Interval(3, 4).contains(x)), + (0, True) + ) + assert splines[0] == b0 + + +def test_repeated_degree_1(): + d = 1 + knots = [0, 0, 1, 2, 2, 3, 4, 4] + splines = bspline_basis_set(d, knots, x) + assert splines[0] == Piecewise((1 - x, Interval(0, 1).contains(x)), + (0, True)) + assert splines[1] == Piecewise((x, Interval(0, 1).contains(x)), + (2 - x, Interval(1, 2).contains(x)), + (0, True)) + assert splines[2] == Piecewise((-1 + x, Interval(1, 2).contains(x)), + (0, True)) + assert splines[3] == Piecewise((3 - x, Interval(2, 3).contains(x)), + (0, True)) + assert splines[4] == Piecewise((-2 + x, Interval(2, 3).contains(x)), + (4 - x, Interval(3, 4).contains(x)), + (0, True)) + assert splines[5] == Piecewise((-3 + x, Interval(3, 4).contains(x)), + (0, True)) + + +def test_repeated_degree_2(): + d = 2 + knots = [0, 0, 1, 2, 2, 3, 4, 4] + splines = bspline_basis_set(d, knots, x) + + assert splines[0] == Piecewise(((-3*x**2/2 + 2*x), And(x <= 1, x >= 0)), + (x**2/2 - 2*x + 2, And(x <= 2, x >= 1)), + (0, True)) + assert splines[1] == Piecewise((x**2/2, And(x <= 1, x >= 0)), + (-3*x**2/2 + 4*x - 2, And(x <= 2, x >= 1)), + (0, True)) + assert splines[2] == Piecewise((x**2 - 2*x + 1, And(x <= 2, x >= 1)), + (x**2 - 6*x + 9, And(x <= 3, x >= 2)), + (0, True)) + assert splines[3] == Piecewise((-3*x**2/2 + 8*x - 10, And(x <= 3, x >= 2)), + (x**2/2 - 4*x + 8, And(x <= 4, x >= 3)), + (0, True)) + assert splines[4] == Piecewise((x**2/2 - 2*x + 2, And(x <= 3, x >= 2)), + (-3*x**2/2 + 10*x - 16, And(x <= 4, x >= 3)), + (0, True)) + +# Tests for interpolating_spline + + +def test_10_points_degree_1(): + d = 1 + X = [-5, 2, 3, 4, 7, 9, 10, 30, 31, 34] + Y = [-10, -2, 2, 4, 7, 6, 20, 45, 19, 25] + spline = interpolating_spline(d, x, X, Y) + + assert spline == Piecewise((x*Rational(8, 7) - Rational(30, 7), (x >= -5) & (x <= 2)), (4*x - 10, (x >= 2) & (x <= 3)), + (2*x - 4, (x >= 3) & (x <= 4)), (x, (x >= 4) & (x <= 7)), + (-x/2 + Rational(21, 2), (x >= 7) & (x <= 9)), (14*x - 120, (x >= 9) & (x <= 10)), + (x*Rational(5, 4) + Rational(15, 2), (x >= 10) & (x <= 30)), (-26*x + 825, (x >= 30) & (x <= 31)), + (2*x - 43, (x >= 31) & (x <= 34))) + + +def test_3_points_degree_2(): + d = 2 + X = [-3, 10, 19] + Y = [3, -4, 30] + spline = interpolating_spline(d, x, X, Y) + + assert spline == Piecewise((505*x**2/2574 - x*Rational(4921, 2574) - Rational(1931, 429), (x >= -3) & (x <= 19))) + + +def test_5_points_degree_2(): + d = 2 + X = [-3, 2, 4, 5, 10] + Y = [-1, 2, 5, 10, 14] + spline = interpolating_spline(d, x, X, Y) + + assert spline == Piecewise((4*x**2/329 + x*Rational(1007, 1645) + Rational(1196, 1645), (x >= -3) & (x <= 3)), + (2701*x**2/1645 - x*Rational(15079, 1645) + Rational(5065, 329), (x >= 3) & (x <= Rational(9, 2))), + (-1319*x**2/1645 + x*Rational(21101, 1645) - Rational(11216, 329), (x >= Rational(9, 2)) & (x <= 10))) + + +@slow +def test_6_points_degree_3(): + d = 3 + X = [-1, 0, 2, 3, 9, 12] + Y = [-4, 3, 3, 7, 9, 20] + spline = interpolating_spline(d, x, X, Y) + + assert spline == Piecewise((6058*x**3/5301 - 18427*x**2/5301 + x*Rational(12622, 5301) + 3, (x >= -1) & (x <= 2)), + (-8327*x**3/5301 + 67883*x**2/5301 - x*Rational(159998, 5301) + Rational(43661, 1767), (x >= 2) & (x <= 3)), + (5414*x**3/47709 - 1386*x**2/589 + x*Rational(4267, 279) - Rational(12232, 589), (x >= 3) & (x <= 12))) + + +def test_issue_19262(): + Delta = symbols('Delta', positive=True) + knots = [i*Delta for i in range(4)] + basis = bspline_basis_set(1, knots, x) + y = symbols('y', nonnegative=True) + basis2 = bspline_basis_set(1, knots, y) + assert basis[0].subs(x, y) == basis2[0] + assert interpolating_spline(1, x, + [Delta*i for i in [1, 2, 4, 7]], [3, 6, 5, 7] + ) == Piecewise((3*x/Delta, (Delta <= x) & (x <= 2*Delta)), + (7 - x/(2*Delta), (x >= 2*Delta) & (x <= 4*Delta)), + (Rational(7, 3) + 2*x/(3*Delta), (x >= 4*Delta) & (x <= 7*Delta))) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_delta_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_delta_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..d5a39d9e352143cf878cf69fa42f454f58be65c9 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_delta_functions.py @@ -0,0 +1,165 @@ +from sympy.core.numbers import (I, nan, oo, pi) +from sympy.core.relational import (Eq, Ne) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.complexes import (adjoint, conjugate, sign, transpose) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.special.delta_functions import (DiracDelta, Heaviside) +from sympy.functions.special.singularity_functions import SingularityFunction +from sympy.simplify.simplify import signsimp + + +from sympy.testing.pytest import raises + +from sympy.core.expr import unchanged + +from sympy.core.function import ArgumentIndexError + + +x, y = symbols('x y') +i = symbols('t', nonzero=True) +j = symbols('j', positive=True) +k = symbols('k', negative=True) + +def test_DiracDelta(): + assert DiracDelta(1) == 0 + assert DiracDelta(5.1) == 0 + assert DiracDelta(-pi) == 0 + assert DiracDelta(5, 7) == 0 + assert DiracDelta(x, 0) == DiracDelta(x) + assert DiracDelta(i) == 0 + assert DiracDelta(j) == 0 + assert DiracDelta(k) == 0 + assert DiracDelta(nan) is nan + assert DiracDelta(0).func is DiracDelta + assert DiracDelta(x).func is DiracDelta + # FIXME: this is generally undefined @ x=0 + # But then limit(Delta(c)*Heaviside(x),x,-oo) + # need's to be implemented. + # assert 0*DiracDelta(x) == 0 + + assert adjoint(DiracDelta(x)) == DiracDelta(x) + assert adjoint(DiracDelta(x - y)) == DiracDelta(x - y) + assert conjugate(DiracDelta(x)) == DiracDelta(x) + assert conjugate(DiracDelta(x - y)) == DiracDelta(x - y) + assert transpose(DiracDelta(x)) == DiracDelta(x) + assert transpose(DiracDelta(x - y)) == DiracDelta(x - y) + + assert DiracDelta(x).diff(x) == DiracDelta(x, 1) + assert DiracDelta(x, 1).diff(x) == DiracDelta(x, 2) + + assert DiracDelta(x).is_simple(x) is True + assert DiracDelta(3*x).is_simple(x) is True + assert DiracDelta(x**2).is_simple(x) is False + assert DiracDelta(sqrt(x)).is_simple(x) is False + assert DiracDelta(x).is_simple(y) is False + + assert DiracDelta(x*y).expand(diracdelta=True, wrt=x) == DiracDelta(x)/abs(y) + assert DiracDelta(x*y).expand(diracdelta=True, wrt=y) == DiracDelta(y)/abs(x) + assert DiracDelta(x**2*y).expand(diracdelta=True, wrt=x) == DiracDelta(x**2*y) + assert DiracDelta(y).expand(diracdelta=True, wrt=x) == DiracDelta(y) + assert DiracDelta((x - 1)*(x - 2)*(x - 3)).expand(diracdelta=True, wrt=x) == ( + DiracDelta(x - 3)/2 + DiracDelta(x - 2) + DiracDelta(x - 1)/2) + + assert DiracDelta(2*x) != DiracDelta(x) # scaling property + assert DiracDelta(x) == DiracDelta(-x) # even function + assert DiracDelta(-x, 2) == DiracDelta(x, 2) + assert DiracDelta(-x, 1) == -DiracDelta(x, 1) # odd deriv is odd + assert DiracDelta(-oo*x) == DiracDelta(oo*x) + assert DiracDelta(x - y) != DiracDelta(y - x) + assert signsimp(DiracDelta(x - y) - DiracDelta(y - x)) == 0 + + assert DiracDelta(x*y).expand(diracdelta=True, wrt=x) == DiracDelta(x)/abs(y) + assert DiracDelta(x*y).expand(diracdelta=True, wrt=y) == DiracDelta(y)/abs(x) + assert DiracDelta(x**2*y).expand(diracdelta=True, wrt=x) == DiracDelta(x**2*y) + assert DiracDelta(y).expand(diracdelta=True, wrt=x) == DiracDelta(y) + assert DiracDelta((x - 1)*(x - 2)*(x - 3)).expand(diracdelta=True) == ( + DiracDelta(x - 3)/2 + DiracDelta(x - 2) + DiracDelta(x - 1)/2) + + raises(ArgumentIndexError, lambda: DiracDelta(x).fdiff(2)) + raises(ValueError, lambda: DiracDelta(x, -1)) + raises(ValueError, lambda: DiracDelta(I)) + raises(ValueError, lambda: DiracDelta(2 + 3*I)) + + +def test_heaviside(): + assert Heaviside(-5) == 0 + assert Heaviside(1) == 1 + assert Heaviside(0) == S.Half + + assert Heaviside(0, x) == x + assert unchanged(Heaviside,x, nan) + assert Heaviside(0, nan) == nan + + h0 = Heaviside(x, 0) + h12 = Heaviside(x, S.Half) + h1 = Heaviside(x, 1) + + assert h0.args == h0.pargs == (x, 0) + assert h1.args == h1.pargs == (x, 1) + assert h12.args == (x, S.Half) + assert h12.pargs == (x,) # default 1/2 suppressed + + assert adjoint(Heaviside(x)) == Heaviside(x) + assert adjoint(Heaviside(x - y)) == Heaviside(x - y) + assert conjugate(Heaviside(x)) == Heaviside(x) + assert conjugate(Heaviside(x - y)) == Heaviside(x - y) + assert transpose(Heaviside(x)) == Heaviside(x) + assert transpose(Heaviside(x - y)) == Heaviside(x - y) + + assert Heaviside(x).diff(x) == DiracDelta(x) + assert Heaviside(x + I).is_Function is True + assert Heaviside(I*x).is_Function is True + + raises(ArgumentIndexError, lambda: Heaviside(x).fdiff(2)) + raises(ValueError, lambda: Heaviside(I)) + raises(ValueError, lambda: Heaviside(2 + 3*I)) + + +def test_rewrite(): + x, y = Symbol('x', real=True), Symbol('y') + assert Heaviside(x).rewrite(Piecewise) == ( + Piecewise((0, x < 0), (Heaviside(0), Eq(x, 0)), (1, True))) + assert Heaviside(y).rewrite(Piecewise) == ( + Piecewise((0, y < 0), (Heaviside(0), Eq(y, 0)), (1, True))) + assert Heaviside(x, y).rewrite(Piecewise) == ( + Piecewise((0, x < 0), (y, Eq(x, 0)), (1, True))) + assert Heaviside(x, 0).rewrite(Piecewise) == ( + Piecewise((0, x <= 0), (1, True))) + assert Heaviside(x, 1).rewrite(Piecewise) == ( + Piecewise((0, x < 0), (1, True))) + assert Heaviside(x, nan).rewrite(Piecewise) == ( + Piecewise((0, x < 0), (nan, Eq(x, 0)), (1, True))) + + assert Heaviside(x).rewrite(sign) == \ + Heaviside(x, H0=Heaviside(0)).rewrite(sign) == \ + Piecewise( + (sign(x)/2 + S(1)/2, Eq(Heaviside(0), S(1)/2)), + (Piecewise( + (sign(x)/2 + S(1)/2, Ne(x, 0)), (Heaviside(0), True)), True) + ) + + assert Heaviside(y).rewrite(sign) == Heaviside(y) + assert Heaviside(x, S.Half).rewrite(sign) == (sign(x)+1)/2 + assert Heaviside(x, y).rewrite(sign) == \ + Piecewise( + (sign(x)/2 + S(1)/2, Eq(y, S(1)/2)), + (Piecewise( + (sign(x)/2 + S(1)/2, Ne(x, 0)), (y, True)), True) + ) + + assert DiracDelta(y).rewrite(Piecewise) == Piecewise((DiracDelta(0), Eq(y, 0)), (0, True)) + assert DiracDelta(y, 1).rewrite(Piecewise) == DiracDelta(y, 1) + assert DiracDelta(x - 5).rewrite(Piecewise) == ( + Piecewise((DiracDelta(0), Eq(x - 5, 0)), (0, True))) + + assert (x*DiracDelta(x - 10)).rewrite(SingularityFunction) == x*SingularityFunction(x, 10, -1) + assert 5*x*y*DiracDelta(y, 1).rewrite(SingularityFunction) == 5*x*y*SingularityFunction(y, 0, -2) + assert DiracDelta(0).rewrite(SingularityFunction) == SingularityFunction(0, 0, -1) + assert DiracDelta(0, 1).rewrite(SingularityFunction) == SingularityFunction(0, 0, -2) + + assert Heaviside(x).rewrite(SingularityFunction) == SingularityFunction(x, 0, 0) + assert 5*x*y*Heaviside(y + 1).rewrite(SingularityFunction) == 5*x*y*SingularityFunction(y, -1, 0) + assert ((x - 3)**3*Heaviside(x - 3)).rewrite(SingularityFunction) == (x - 3)**3*SingularityFunction(x, 3, 0) + assert Heaviside(0).rewrite(SingularityFunction) == S.Half diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_elliptic_integrals.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_elliptic_integrals.py new file mode 100644 index 0000000000000000000000000000000000000000..a11e531af32301a00b6fc864064d02f9318929e1 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_elliptic_integrals.py @@ -0,0 +1,181 @@ +from sympy.core.numbers import (I, Rational, oo, pi, zoo) +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, Symbol) +from sympy.functions.elementary.hyperbolic import atanh +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (sin, tan) +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import (hyper, meijerg) +from sympy.integrals.integrals import Integral +from sympy.series.order import O +from sympy.functions.special.elliptic_integrals import (elliptic_k as K, + elliptic_f as F, elliptic_e as E, elliptic_pi as P) +from sympy.core.random import (test_derivative_numerically as td, + random_complex_number as randcplx, + verify_numerically as tn) +from sympy.abc import z, m, n + +i = Symbol('i', integer=True) +j = Symbol('k', integer=True, positive=True) +t = Dummy('t') + +def test_K(): + assert K(0) == pi/2 + assert K(S.Half) == 8*pi**Rational(3, 2)/gamma(Rational(-1, 4))**2 + assert K(1) is zoo + assert K(-1) == gamma(Rational(1, 4))**2/(4*sqrt(2*pi)) + assert K(oo) == 0 + assert K(-oo) == 0 + assert K(I*oo) == 0 + assert K(-I*oo) == 0 + assert K(zoo) == 0 + + assert K(z).diff(z) == (E(z) - (1 - z)*K(z))/(2*z*(1 - z)) + assert td(K(z), z) + + zi = Symbol('z', real=False) + assert K(zi).conjugate() == K(zi.conjugate()) + zr = Symbol('z', negative=True) + assert K(zr).conjugate() == K(zr) + + assert K(z).rewrite(hyper) == \ + (pi/2)*hyper((S.Half, S.Half), (S.One,), z) + assert tn(K(z), (pi/2)*hyper((S.Half, S.Half), (S.One,), z)) + assert K(z).rewrite(meijerg) == \ + meijerg(((S.Half, S.Half), []), ((S.Zero,), (S.Zero,)), -z)/2 + assert tn(K(z), meijerg(((S.Half, S.Half), []), ((S.Zero,), (S.Zero,)), -z)/2) + + assert K(z).series(z) == pi/2 + pi*z/8 + 9*pi*z**2/128 + \ + 25*pi*z**3/512 + 1225*pi*z**4/32768 + 3969*pi*z**5/131072 + O(z**6) + + assert K(m).rewrite(Integral).dummy_eq( + Integral(1/sqrt(1 - m*sin(t)**2), (t, 0, pi/2))) + +def test_F(): + assert F(z, 0) == z + assert F(0, m) == 0 + assert F(pi*i/2, m) == i*K(m) + assert F(z, oo) == 0 + assert F(z, -oo) == 0 + + assert F(-z, m) == -F(z, m) + + assert F(z, m).diff(z) == 1/sqrt(1 - m*sin(z)**2) + assert F(z, m).diff(m) == E(z, m)/(2*m*(1 - m)) - F(z, m)/(2*m) - \ + sin(2*z)/(4*(1 - m)*sqrt(1 - m*sin(z)**2)) + r = randcplx() + assert td(F(z, r), z) + assert td(F(r, m), m) + + mi = Symbol('m', real=False) + assert F(z, mi).conjugate() == F(z.conjugate(), mi.conjugate()) + mr = Symbol('m', negative=True) + assert F(z, mr).conjugate() == F(z.conjugate(), mr) + + assert F(z, m).series(z) == \ + z + z**5*(3*m**2/40 - m/30) + m*z**3/6 + O(z**6) + + assert F(z, m).rewrite(Integral).dummy_eq( + Integral(1/sqrt(1 - m*sin(t)**2), (t, 0, z))) + +def test_E(): + assert E(z, 0) == z + assert E(0, m) == 0 + assert E(i*pi/2, m) == i*E(m) + assert E(z, oo) is zoo + assert E(z, -oo) is zoo + assert E(0) == pi/2 + assert E(1) == 1 + assert E(oo) == I*oo + assert E(-oo) is oo + assert E(zoo) is zoo + + assert E(-z, m) == -E(z, m) + + assert E(z, m).diff(z) == sqrt(1 - m*sin(z)**2) + assert E(z, m).diff(m) == (E(z, m) - F(z, m))/(2*m) + assert E(z).diff(z) == (E(z) - K(z))/(2*z) + r = randcplx() + assert td(E(r, m), m) + assert td(E(z, r), z) + assert td(E(z), z) + + mi = Symbol('m', real=False) + assert E(z, mi).conjugate() == E(z.conjugate(), mi.conjugate()) + assert E(mi).conjugate() == E(mi.conjugate()) + mr = Symbol('m', negative=True) + assert E(z, mr).conjugate() == E(z.conjugate(), mr) + assert E(mr).conjugate() == E(mr) + + assert E(z).rewrite(hyper) == (pi/2)*hyper((Rational(-1, 2), S.Half), (S.One,), z) + assert tn(E(z), (pi/2)*hyper((Rational(-1, 2), S.Half), (S.One,), z)) + assert E(z).rewrite(meijerg) == \ + -meijerg(((S.Half, Rational(3, 2)), []), ((S.Zero,), (S.Zero,)), -z)/4 + assert tn(E(z), -meijerg(((S.Half, Rational(3, 2)), []), ((S.Zero,), (S.Zero,)), -z)/4) + + assert E(z, m).series(z) == \ + z + z**5*(-m**2/40 + m/30) - m*z**3/6 + O(z**6) + assert E(z).series(z) == pi/2 - pi*z/8 - 3*pi*z**2/128 - \ + 5*pi*z**3/512 - 175*pi*z**4/32768 - 441*pi*z**5/131072 + O(z**6) + assert E(4*z/(z+1)).series(z) == \ + pi/2 - pi*z/2 + pi*z**2/8 - 3*pi*z**3/8 - 15*pi*z**4/128 - 93*pi*z**5/128 + O(z**6) + + assert E(z, m).rewrite(Integral).dummy_eq( + Integral(sqrt(1 - m*sin(t)**2), (t, 0, z))) + assert E(m).rewrite(Integral).dummy_eq( + Integral(sqrt(1 - m*sin(t)**2), (t, 0, pi/2))) + +def test_P(): + assert P(0, z, m) == F(z, m) + assert P(1, z, m) == F(z, m) + \ + (sqrt(1 - m*sin(z)**2)*tan(z) - E(z, m))/(1 - m) + assert P(n, i*pi/2, m) == i*P(n, m) + assert P(n, z, 0) == atanh(sqrt(n - 1)*tan(z))/sqrt(n - 1) + assert P(n, z, n) == F(z, n) - P(1, z, n) + tan(z)/sqrt(1 - n*sin(z)**2) + assert P(oo, z, m) == 0 + assert P(-oo, z, m) == 0 + assert P(n, z, oo) == 0 + assert P(n, z, -oo) == 0 + assert P(0, m) == K(m) + assert P(1, m) is zoo + assert P(n, 0) == pi/(2*sqrt(1 - n)) + assert P(2, 1) is -oo + assert P(-1, 1) is oo + assert P(n, n) == E(n)/(1 - n) + + assert P(n, -z, m) == -P(n, z, m) + + ni, mi = Symbol('n', real=False), Symbol('m', real=False) + assert P(ni, z, mi).conjugate() == \ + P(ni.conjugate(), z.conjugate(), mi.conjugate()) + nr, mr = Symbol('n', negative=True), \ + Symbol('m', negative=True) + assert P(nr, z, mr).conjugate() == P(nr, z.conjugate(), mr) + assert P(n, m).conjugate() == P(n.conjugate(), m.conjugate()) + + assert P(n, z, m).diff(n) == (E(z, m) + (m - n)*F(z, m)/n + + (n**2 - m)*P(n, z, m)/n - n*sqrt(1 - + m*sin(z)**2)*sin(2*z)/(2*(1 - n*sin(z)**2)))/(2*(m - n)*(n - 1)) + assert P(n, z, m).diff(z) == 1/(sqrt(1 - m*sin(z)**2)*(1 - n*sin(z)**2)) + assert P(n, z, m).diff(m) == (E(z, m)/(m - 1) + P(n, z, m) - + m*sin(2*z)/(2*(m - 1)*sqrt(1 - m*sin(z)**2)))/(2*(n - m)) + assert P(n, m).diff(n) == (E(m) + (m - n)*K(m)/n + + (n**2 - m)*P(n, m)/n)/(2*(m - n)*(n - 1)) + assert P(n, m).diff(m) == (E(m)/(m - 1) + P(n, m))/(2*(n - m)) + + # These tests fail due to + # https://github.com/fredrik-johansson/mpmath/issues/571#issuecomment-777201962 + # https://github.com/sympy/sympy/issues/20933#issuecomment-777080385 + # + # rx, ry = randcplx(), randcplx() + # assert td(P(n, rx, ry), n) + # assert td(P(rx, z, ry), z) + # assert td(P(rx, ry, m), m) + + assert P(n, z, m).series(z) == z + z**3*(m/6 + n/3) + \ + z**5*(3*m**2/40 + m*n/10 - m/30 + n**2/5 - n/15) + O(z**6) + + assert P(n, z, m).rewrite(Integral).dummy_eq( + Integral(1/((1 - n*sin(t)**2)*sqrt(1 - m*sin(t)**2)), (t, 0, z))) + assert P(n, m).rewrite(Integral).dummy_eq( + Integral(1/((1 - n*sin(t)**2)*sqrt(1 - m*sin(t)**2)), (t, 0, pi/2))) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_error_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_error_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..073371d3d584b97936729dc2e39c833ac347559b --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_error_functions.py @@ -0,0 +1,860 @@ +from sympy.core.function import (diff, expand, expand_func) +from sympy.core import EulerGamma +from sympy.core.numbers import (E, Float, I, Rational, nan, oo, pi) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols, Dummy) +from sympy.functions.elementary.complexes import (conjugate, im, polar_lift, re) +from sympy.functions.elementary.exponential import (exp, exp_polar, log) +from sympy.functions.elementary.hyperbolic import (cosh, sinh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (cos, sin, sinc) +from sympy.functions.special.error_functions import (Chi, Ci, E1, Ei, Li, Shi, Si, erf, erf2, erf2inv, erfc, erfcinv, erfi, erfinv, expint, fresnelc, fresnels, li) +from sympy.functions.special.gamma_functions import (gamma, uppergamma) +from sympy.functions.special.hyper import (hyper, meijerg) +from sympy.integrals.integrals import (Integral, integrate) +from sympy.series.gruntz import gruntz +from sympy.series.limits import limit +from sympy.series.order import O +from sympy.core.expr import unchanged +from sympy.core.function import ArgumentIndexError +from sympy.functions.special.error_functions import _erfs, _eis +from sympy.testing.pytest import raises + +x, y, z = symbols('x,y,z') +w = Symbol("w", real=True) +n = Symbol("n", integer=True) +t = Dummy('t') + + +def test_erf(): + assert erf(nan) is nan + + assert erf(oo) == 1 + assert erf(-oo) == -1 + + assert erf(0) is S.Zero + + assert erf(I*oo) == oo*I + assert erf(-I*oo) == -oo*I + + assert erf(-2) == -erf(2) + assert erf(-x*y) == -erf(x*y) + assert erf(-x - y) == -erf(x + y) + + assert erf(erfinv(x)) == x + assert erf(erfcinv(x)) == 1 - x + assert erf(erf2inv(0, x)) == x + assert erf(erf2inv(0, x, evaluate=False)) == x # To cover code in erf + assert erf(erf2inv(0, erf(erfcinv(1 - erf(erfinv(x)))))) == x + + alpha = symbols('alpha', extended_real=True) + assert erf(alpha).is_real is True + assert erf(alpha).is_finite is True + alpha = symbols('alpha', extended_real=False) + assert erf(alpha).is_real is None + assert erf(alpha).is_finite is None + assert erf(alpha).is_zero is None + assert erf(alpha).is_positive is None + assert erf(alpha).is_negative is None + alpha = symbols('alpha', extended_positive=True) + assert erf(alpha).is_positive is True + alpha = symbols('alpha', extended_negative=True) + assert erf(alpha).is_negative is True + assert erf(I).is_real is False + assert erf(0, evaluate=False).is_real + assert erf(0, evaluate=False).is_zero + + assert conjugate(erf(z)) == erf(conjugate(z)) + + assert erf(x).as_leading_term(x) == 2*x/sqrt(pi) + assert erf(x*y).as_leading_term(y) == 2*x*y/sqrt(pi) + assert (erf(x*y)/erf(y)).as_leading_term(y) == x + assert erf(1/x).as_leading_term(x) == S.One + + assert erf(z).rewrite('uppergamma') == sqrt(z**2)*(1 - erfc(sqrt(z**2)))/z + assert erf(z).rewrite('erfc') == S.One - erfc(z) + assert erf(z).rewrite('erfi') == -I*erfi(I*z) + assert erf(z).rewrite('fresnels') == (1 + I)*(fresnelc(z*(1 - I)/sqrt(pi)) - + I*fresnels(z*(1 - I)/sqrt(pi))) + assert erf(z).rewrite('fresnelc') == (1 + I)*(fresnelc(z*(1 - I)/sqrt(pi)) - + I*fresnels(z*(1 - I)/sqrt(pi))) + assert erf(z).rewrite('hyper') == 2*z*hyper([S.Half], [3*S.Half], -z**2)/sqrt(pi) + assert erf(z).rewrite('meijerg') == z*meijerg([S.Half], [], [0], [Rational(-1, 2)], z**2)/sqrt(pi) + assert erf(z).rewrite('expint') == sqrt(z**2)/z - z*expint(S.Half, z**2)/sqrt(S.Pi) + + assert limit(exp(x)*exp(x**2)*(erf(x + 1/exp(x)) - erf(x)), x, oo) == \ + 2/sqrt(pi) + assert limit((1 - erf(z))*exp(z**2)*z, z, oo) == 1/sqrt(pi) + assert limit((1 - erf(x))*exp(x**2)*sqrt(pi)*x, x, oo) == 1 + assert limit(((1 - erf(x))*exp(x**2)*sqrt(pi)*x - 1)*2*x**2, x, oo) == -1 + assert limit(erf(x)/x, x, 0) == 2/sqrt(pi) + assert limit(x**(-4) - sqrt(pi)*erf(x**2) / (2*x**6), x, 0) == S(1)/3 + + assert erf(x).as_real_imag() == \ + (erf(re(x) - I*im(x))/2 + erf(re(x) + I*im(x))/2, + -I*(-erf(re(x) - I*im(x)) + erf(re(x) + I*im(x)))/2) + + assert erf(x).as_real_imag(deep=False) == \ + (erf(re(x) - I*im(x))/2 + erf(re(x) + I*im(x))/2, + -I*(-erf(re(x) - I*im(x)) + erf(re(x) + I*im(x)))/2) + + assert erf(w).as_real_imag() == (erf(w), 0) + assert erf(w).as_real_imag(deep=False) == (erf(w), 0) + # issue 13575 + assert erf(I).as_real_imag() == (0, -I*erf(I)) + + raises(ArgumentIndexError, lambda: erf(x).fdiff(2)) + + assert erf(x).inverse() == erfinv + + +def test_erf_series(): + assert erf(x).series(x, 0, 7) == 2*x/sqrt(pi) - \ + 2*x**3/3/sqrt(pi) + x**5/5/sqrt(pi) + O(x**7) + + assert erf(x).series(x, oo) == \ + -exp(-x**2)*(3/(4*x**5) - 1/(2*x**3) + 1/x + O(x**(-6), (x, oo)))/sqrt(pi) + 1 + assert erf(x**2).series(x, oo, n=8) == \ + (-1/(2*x**6) + x**(-2) + O(x**(-8), (x, oo)))*exp(-x**4)/sqrt(pi)*-1 + 1 + assert erf(sqrt(x)).series(x, oo, n=3) == (sqrt(1/x) - (1/x)**(S(3)/2)/2\ + + 3*(1/x)**(S(5)/2)/4 + O(x**(-3), (x, oo)))*exp(-x)/sqrt(pi)*-1 + 1 + + +def test_erf_evalf(): + assert abs( erf(Float(2.0)) - 0.995322265 ) < 1E-8 # XXX + + +def test__erfs(): + assert _erfs(z).diff(z) == -2/sqrt(S.Pi) + 2*z*_erfs(z) + + assert _erfs(1/z).series(z) == \ + z/sqrt(pi) - z**3/(2*sqrt(pi)) + 3*z**5/(4*sqrt(pi)) + O(z**6) + + assert expand(erf(z).rewrite('tractable').diff(z).rewrite('intractable')) \ + == erf(z).diff(z) + assert _erfs(z).rewrite("intractable") == (-erf(z) + 1)*exp(z**2) + raises(ArgumentIndexError, lambda: _erfs(z).fdiff(2)) + + +def test_erfc(): + assert erfc(nan) is nan + + assert erfc(oo) is S.Zero + assert erfc(-oo) == 2 + + assert erfc(0) == 1 + + assert erfc(I*oo) == -oo*I + assert erfc(-I*oo) == oo*I + + assert erfc(-x) == S(2) - erfc(x) + assert erfc(erfcinv(x)) == x + + alpha = symbols('alpha', extended_real=True) + assert erfc(alpha).is_real is True + alpha = symbols('alpha', extended_real=False) + assert erfc(alpha).is_real is None + assert erfc(I).is_real is False + assert erfc(0, evaluate=False).is_real + assert erfc(0, evaluate=False).is_zero is False + + assert erfc(erfinv(x)) == 1 - x + + assert conjugate(erfc(z)) == erfc(conjugate(z)) + + assert erfc(x).as_leading_term(x) is S.One + assert erfc(1/x).as_leading_term(x) == S.Zero + + assert erfc(z).rewrite('erf') == 1 - erf(z) + assert erfc(z).rewrite('erfi') == 1 + I*erfi(I*z) + assert erfc(z).rewrite('fresnels') == 1 - (1 + I)*(fresnelc(z*(1 - I)/sqrt(pi)) - + I*fresnels(z*(1 - I)/sqrt(pi))) + assert erfc(z).rewrite('fresnelc') == 1 - (1 + I)*(fresnelc(z*(1 - I)/sqrt(pi)) - + I*fresnels(z*(1 - I)/sqrt(pi))) + assert erfc(z).rewrite('hyper') == 1 - 2*z*hyper([S.Half], [3*S.Half], -z**2)/sqrt(pi) + assert erfc(z).rewrite('meijerg') == 1 - z*meijerg([S.Half], [], [0], [Rational(-1, 2)], z**2)/sqrt(pi) + assert erfc(z).rewrite('uppergamma') == 1 - sqrt(z**2)*(1 - erfc(sqrt(z**2)))/z + assert erfc(z).rewrite('expint') == S.One - sqrt(z**2)/z + z*expint(S.Half, z**2)/sqrt(S.Pi) + assert erfc(z).rewrite('tractable') == _erfs(z)*exp(-z**2) + assert expand_func(erf(x) + erfc(x)) is S.One + + assert erfc(x).as_real_imag() == \ + (erfc(re(x) - I*im(x))/2 + erfc(re(x) + I*im(x))/2, + -I*(-erfc(re(x) - I*im(x)) + erfc(re(x) + I*im(x)))/2) + + assert erfc(x).as_real_imag(deep=False) == \ + (erfc(re(x) - I*im(x))/2 + erfc(re(x) + I*im(x))/2, + -I*(-erfc(re(x) - I*im(x)) + erfc(re(x) + I*im(x)))/2) + + assert erfc(w).as_real_imag() == (erfc(w), 0) + assert erfc(w).as_real_imag(deep=False) == (erfc(w), 0) + raises(ArgumentIndexError, lambda: erfc(x).fdiff(2)) + + assert erfc(x).inverse() == erfcinv + + +def test_erfc_series(): + assert erfc(x).series(x, 0, 7) == 1 - 2*x/sqrt(pi) + \ + 2*x**3/3/sqrt(pi) - x**5/5/sqrt(pi) + O(x**7) + + assert erfc(x).series(x, oo) == \ + (3/(4*x**5) - 1/(2*x**3) + 1/x + O(x**(-6), (x, oo)))*exp(-x**2)/sqrt(pi) + + +def test_erfc_evalf(): + assert abs( erfc(Float(2.0)) - 0.00467773 ) < 1E-8 # XXX + + +def test_erfi(): + assert erfi(nan) is nan + + assert erfi(oo) is S.Infinity + assert erfi(-oo) is S.NegativeInfinity + + assert erfi(0) is S.Zero + + assert erfi(I*oo) == I + assert erfi(-I*oo) == -I + + assert erfi(-x) == -erfi(x) + + assert erfi(I*erfinv(x)) == I*x + assert erfi(I*erfcinv(x)) == I*(1 - x) + assert erfi(I*erf2inv(0, x)) == I*x + assert erfi(I*erf2inv(0, x, evaluate=False)) == I*x # To cover code in erfi + + assert erfi(I).is_real is False + assert erfi(0, evaluate=False).is_real + assert erfi(0, evaluate=False).is_zero + + assert conjugate(erfi(z)) == erfi(conjugate(z)) + + assert erfi(x).as_leading_term(x) == 2*x/sqrt(pi) + assert erfi(x*y).as_leading_term(y) == 2*x*y/sqrt(pi) + assert (erfi(x*y)/erfi(y)).as_leading_term(y) == x + assert erfi(1/x).as_leading_term(x) == erfi(1/x) + + assert erfi(z).rewrite('erf') == -I*erf(I*z) + assert erfi(z).rewrite('erfc') == I*erfc(I*z) - I + assert erfi(z).rewrite('fresnels') == (1 - I)*(fresnelc(z*(1 + I)/sqrt(pi)) - + I*fresnels(z*(1 + I)/sqrt(pi))) + assert erfi(z).rewrite('fresnelc') == (1 - I)*(fresnelc(z*(1 + I)/sqrt(pi)) - + I*fresnels(z*(1 + I)/sqrt(pi))) + assert erfi(z).rewrite('hyper') == 2*z*hyper([S.Half], [3*S.Half], z**2)/sqrt(pi) + assert erfi(z).rewrite('meijerg') == z*meijerg([S.Half], [], [0], [Rational(-1, 2)], -z**2)/sqrt(pi) + assert erfi(z).rewrite('uppergamma') == (sqrt(-z**2)/z*(uppergamma(S.Half, + -z**2)/sqrt(S.Pi) - S.One)) + assert erfi(z).rewrite('expint') == sqrt(-z**2)/z - z*expint(S.Half, -z**2)/sqrt(S.Pi) + assert erfi(z).rewrite('tractable') == -I*(-_erfs(I*z)*exp(z**2) + 1) + assert expand_func(erfi(I*z)) == I*erf(z) + + assert erfi(x).as_real_imag() == \ + (erfi(re(x) - I*im(x))/2 + erfi(re(x) + I*im(x))/2, + -I*(-erfi(re(x) - I*im(x)) + erfi(re(x) + I*im(x)))/2) + assert erfi(x).as_real_imag(deep=False) == \ + (erfi(re(x) - I*im(x))/2 + erfi(re(x) + I*im(x))/2, + -I*(-erfi(re(x) - I*im(x)) + erfi(re(x) + I*im(x)))/2) + + assert erfi(w).as_real_imag() == (erfi(w), 0) + assert erfi(w).as_real_imag(deep=False) == (erfi(w), 0) + + raises(ArgumentIndexError, lambda: erfi(x).fdiff(2)) + + +def test_erfi_series(): + assert erfi(x).series(x, 0, 7) == 2*x/sqrt(pi) + \ + 2*x**3/3/sqrt(pi) + x**5/5/sqrt(pi) + O(x**7) + + assert erfi(x).series(x, oo) == \ + (3/(4*x**5) + 1/(2*x**3) + 1/x + O(x**(-6), (x, oo)))*exp(x**2)/sqrt(pi) - I + + +def test_erfi_evalf(): + assert abs( erfi(Float(2.0)) - 18.5648024145756 ) < 1E-13 # XXX + + +def test_erf2(): + + assert erf2(0, 0) is S.Zero + assert erf2(x, x) is S.Zero + assert erf2(nan, 0) is nan + + assert erf2(-oo, y) == erf(y) + 1 + assert erf2( oo, y) == erf(y) - 1 + assert erf2( x, oo) == 1 - erf(x) + assert erf2( x,-oo) == -1 - erf(x) + assert erf2(x, erf2inv(x, y)) == y + + assert erf2(-x, -y) == -erf2(x,y) + assert erf2(-x, y) == erf(y) + erf(x) + assert erf2( x, -y) == -erf(y) - erf(x) + assert erf2(x, y).rewrite('fresnels') == erf(y).rewrite(fresnels)-erf(x).rewrite(fresnels) + assert erf2(x, y).rewrite('fresnelc') == erf(y).rewrite(fresnelc)-erf(x).rewrite(fresnelc) + assert erf2(x, y).rewrite('hyper') == erf(y).rewrite(hyper)-erf(x).rewrite(hyper) + assert erf2(x, y).rewrite('meijerg') == erf(y).rewrite(meijerg)-erf(x).rewrite(meijerg) + assert erf2(x, y).rewrite('uppergamma') == erf(y).rewrite(uppergamma) - erf(x).rewrite(uppergamma) + assert erf2(x, y).rewrite('expint') == erf(y).rewrite(expint)-erf(x).rewrite(expint) + + assert erf2(I, 0).is_real is False + assert erf2(0, 0, evaluate=False).is_real + assert erf2(0, 0, evaluate=False).is_zero + assert erf2(x, x, evaluate=False).is_zero + assert erf2(x, y).is_zero is None + + assert expand_func(erf(x) + erf2(x, y)) == erf(y) + + assert conjugate(erf2(x, y)) == erf2(conjugate(x), conjugate(y)) + + assert erf2(x, y).rewrite('erf') == erf(y) - erf(x) + assert erf2(x, y).rewrite('erfc') == erfc(x) - erfc(y) + assert erf2(x, y).rewrite('erfi') == I*(erfi(I*x) - erfi(I*y)) + + assert erf2(x, y).diff(x) == erf2(x, y).fdiff(1) + assert erf2(x, y).diff(y) == erf2(x, y).fdiff(2) + assert erf2(x, y).diff(x) == -2*exp(-x**2)/sqrt(pi) + assert erf2(x, y).diff(y) == 2*exp(-y**2)/sqrt(pi) + raises(ArgumentIndexError, lambda: erf2(x, y).fdiff(3)) + + assert erf2(x, y).is_extended_real is None + xr, yr = symbols('xr yr', extended_real=True) + assert erf2(xr, yr).is_extended_real is True + + +def test_erfinv(): + assert erfinv(0) is S.Zero + assert erfinv(1) is S.Infinity + assert erfinv(nan) is S.NaN + assert erfinv(-1) is S.NegativeInfinity + + assert erfinv(erf(w)) == w + assert erfinv(erf(-w)) == -w + + assert erfinv(x).diff() == sqrt(pi)*exp(erfinv(x)**2)/2 + raises(ArgumentIndexError, lambda: erfinv(x).fdiff(2)) + + assert erfinv(z).rewrite('erfcinv') == erfcinv(1-z) + assert erfinv(z).inverse() == erf + + +def test_erfinv_evalf(): + assert abs( erfinv(Float(0.2)) - 0.179143454621292 ) < 1E-13 + + +def test_erfcinv(): + assert erfcinv(1) is S.Zero + assert erfcinv(0) is S.Infinity + assert erfcinv(0, evaluate=False).is_infinite is True + assert erfcinv(2, evaluate=False).is_infinite is True + assert erfcinv(nan) is S.NaN + + assert erfcinv(x).diff() == -sqrt(pi)*exp(erfcinv(x)**2)/2 + raises(ArgumentIndexError, lambda: erfcinv(x).fdiff(2)) + + assert erfcinv(z).rewrite('erfinv') == erfinv(1-z) + assert erfcinv(z).inverse() == erfc + + +def test_erf2inv(): + assert erf2inv(0, 0) is S.Zero + assert erf2inv(0, 1) is S.Infinity + assert erf2inv(1, 0) is S.One + assert erf2inv(0, y) == erfinv(y) + assert erf2inv(oo, y) == erfcinv(-y) + assert erf2inv(x, 0) == x + assert erf2inv(x, oo) == erfinv(x) + assert erf2inv(nan, 0) is nan + assert erf2inv(0, nan) is nan + + assert erf2inv(x, y).diff(x) == exp(-x**2 + erf2inv(x, y)**2) + assert erf2inv(x, y).diff(y) == sqrt(pi)*exp(erf2inv(x, y)**2)/2 + raises(ArgumentIndexError, lambda: erf2inv(x, y).fdiff(3)) + + +# NOTE we multiply by exp_polar(I*pi) and need this to be on the principal +# branch, hence take x in the lower half plane (d=0). + + +def mytn(expr1, expr2, expr3, x, d=0): + from sympy.core.random import verify_numerically, random_complex_number + subs = {} + for a in expr1.free_symbols: + if a != x: + subs[a] = random_complex_number() + return expr2 == expr3 and verify_numerically(expr1.subs(subs), + expr2.subs(subs), x, d=d) + + +def mytd(expr1, expr2, x): + from sympy.core.random import test_derivative_numerically, \ + random_complex_number + subs = {} + for a in expr1.free_symbols: + if a != x: + subs[a] = random_complex_number() + return expr1.diff(x) == expr2 and test_derivative_numerically(expr1.subs(subs), x) + + +def tn_branch(func, s=None): + from sympy.core.random import uniform + + def fn(x): + if s is None: + return func(x) + return func(s, x) + c = uniform(1, 5) + expr = fn(c*exp_polar(I*pi)) - fn(c*exp_polar(-I*pi)) + eps = 1e-15 + expr2 = fn(-c + eps*I) - fn(-c - eps*I) + return abs(expr.n() - expr2.n()).n() < 1e-10 + + +def test_ei(): + assert Ei(0) is S.NegativeInfinity + assert Ei(oo) is S.Infinity + assert Ei(-oo) is S.Zero + + assert tn_branch(Ei) + assert mytd(Ei(x), exp(x)/x, x) + assert mytn(Ei(x), Ei(x).rewrite(uppergamma), + -uppergamma(0, x*polar_lift(-1)) - I*pi, x) + assert mytn(Ei(x), Ei(x).rewrite(expint), + -expint(1, x*polar_lift(-1)) - I*pi, x) + assert Ei(x).rewrite(expint).rewrite(Ei) == Ei(x) + assert Ei(x*exp_polar(2*I*pi)) == Ei(x) + 2*I*pi + assert Ei(x*exp_polar(-2*I*pi)) == Ei(x) - 2*I*pi + + assert mytn(Ei(x), Ei(x).rewrite(Shi), Chi(x) + Shi(x), x) + assert mytn(Ei(x*polar_lift(I)), Ei(x*polar_lift(I)).rewrite(Si), + Ci(x) + I*Si(x) + I*pi/2, x) + + assert Ei(log(x)).rewrite(li) == li(x) + assert Ei(2*log(x)).rewrite(li) == li(x**2) + + assert gruntz(Ei(x+exp(-x))*exp(-x)*x, x, oo) == 1 + + assert Ei(x).series(x) == EulerGamma + log(x) + x + x**2/4 + \ + x**3/18 + x**4/96 + x**5/600 + O(x**6) + assert Ei(x).series(x, 1, 3) == Ei(1) + E*(x - 1) + O((x - 1)**3, (x, 1)) + assert Ei(x).series(x, oo) == \ + (120/x**5 + 24/x**4 + 6/x**3 + 2/x**2 + 1/x + 1 + O(x**(-6), (x, oo)))*exp(x)/x + assert Ei(x).series(x, -oo) == \ + (120/x**5 + 24/x**4 + 6/x**3 + 2/x**2 + 1/x + 1 + O(x**(-6), (x, -oo)))*exp(x)/x + assert Ei(-x).series(x, oo) == \ + -((-120/x**5 + 24/x**4 - 6/x**3 + 2/x**2 - 1/x + 1 + O(x**(-6), (x, oo)))*exp(-x)/x) + + assert str(Ei(cos(2)).evalf(n=10)) == '-0.6760647401' + raises(ArgumentIndexError, lambda: Ei(x).fdiff(2)) + + +def test_expint(): + assert mytn(expint(x, y), expint(x, y).rewrite(uppergamma), + y**(x - 1)*uppergamma(1 - x, y), x) + assert mytd( + expint(x, y), -y**(x - 1)*meijerg([], [1, 1], [0, 0, 1 - x], [], y), x) + assert mytd(expint(x, y), -expint(x - 1, y), y) + assert mytn(expint(1, x), expint(1, x).rewrite(Ei), + -Ei(x*polar_lift(-1)) + I*pi, x) + + assert expint(-4, x) == exp(-x)/x + 4*exp(-x)/x**2 + 12*exp(-x)/x**3 \ + + 24*exp(-x)/x**4 + 24*exp(-x)/x**5 + assert expint(Rational(-3, 2), x) == \ + exp(-x)/x + 3*exp(-x)/(2*x**2) + 3*sqrt(pi)*erfc(sqrt(x))/(4*x**S('5/2')) + + assert tn_branch(expint, 1) + assert tn_branch(expint, 2) + assert tn_branch(expint, 3) + assert tn_branch(expint, 1.7) + assert tn_branch(expint, pi) + + assert expint(y, x*exp_polar(2*I*pi)) == \ + x**(y - 1)*(exp(2*I*pi*y) - 1)*gamma(-y + 1) + expint(y, x) + assert expint(y, x*exp_polar(-2*I*pi)) == \ + x**(y - 1)*(exp(-2*I*pi*y) - 1)*gamma(-y + 1) + expint(y, x) + assert expint(2, x*exp_polar(2*I*pi)) == 2*I*pi*x + expint(2, x) + assert expint(2, x*exp_polar(-2*I*pi)) == -2*I*pi*x + expint(2, x) + assert expint(1, x).rewrite(Ei).rewrite(expint) == expint(1, x) + assert expint(x, y).rewrite(Ei) == expint(x, y) + assert expint(x, y).rewrite(Ci) == expint(x, y) + + assert mytn(E1(x), E1(x).rewrite(Shi), Shi(x) - Chi(x), x) + assert mytn(E1(polar_lift(I)*x), E1(polar_lift(I)*x).rewrite(Si), + -Ci(x) + I*Si(x) - I*pi/2, x) + + assert mytn(expint(2, x), expint(2, x).rewrite(Ei).rewrite(expint), + -x*E1(x) + exp(-x), x) + assert mytn(expint(3, x), expint(3, x).rewrite(Ei).rewrite(expint), + x**2*E1(x)/2 + (1 - x)*exp(-x)/2, x) + + assert expint(Rational(3, 2), z).nseries(z) == \ + 2 + 2*z - z**2/3 + z**3/15 - z**4/84 + z**5/540 - \ + 2*sqrt(pi)*sqrt(z) + O(z**6) + + assert E1(z).series(z) == -EulerGamma - log(z) + z - \ + z**2/4 + z**3/18 - z**4/96 + z**5/600 + O(z**6) + + assert expint(4, z).series(z) == Rational(1, 3) - z/2 + z**2/2 + \ + z**3*(log(z)/6 - Rational(11, 36) + EulerGamma/6 - I*pi/6) - z**4/24 + \ + z**5/240 + O(z**6) + + assert expint(n, x).series(x, oo, n=3) == \ + (n*(n + 1)/x**2 - n/x + 1 + O(x**(-3), (x, oo)))*exp(-x)/x + + assert expint(z, y).series(z, 0, 2) == exp(-y)/y - z*meijerg(((), (1, 1)), + ((0, 0, 1), ()), y)/y + O(z**2) + raises(ArgumentIndexError, lambda: expint(x, y).fdiff(3)) + + neg = Symbol('neg', negative=True) + assert Ei(neg).rewrite(Si) == Shi(neg) + Chi(neg) - I*pi + + +def test__eis(): + assert _eis(z).diff(z) == -_eis(z) + 1/z + + assert _eis(1/z).series(z) == \ + z + z**2 + 2*z**3 + 6*z**4 + 24*z**5 + O(z**6) + + assert Ei(z).rewrite('tractable') == exp(z)*_eis(z) + assert li(z).rewrite('tractable') == z*_eis(log(z)) + + assert _eis(z).rewrite('intractable') == exp(-z)*Ei(z) + + assert expand(li(z).rewrite('tractable').diff(z).rewrite('intractable')) \ + == li(z).diff(z) + + assert expand(Ei(z).rewrite('tractable').diff(z).rewrite('intractable')) \ + == Ei(z).diff(z) + + assert _eis(z).series(z, n=3) == EulerGamma + log(z) + z*(-log(z) - \ + EulerGamma + 1) + z**2*(log(z)/2 - Rational(3, 4) + EulerGamma/2)\ + + O(z**3*log(z)) + raises(ArgumentIndexError, lambda: _eis(z).fdiff(2)) + + +def tn_arg(func): + def test(arg, e1, e2): + from sympy.core.random import uniform + v = uniform(1, 5) + v1 = func(arg*x).subs(x, v).n() + v2 = func(e1*v + e2*1e-15).n() + return abs(v1 - v2).n() < 1e-10 + return test(exp_polar(I*pi/2), I, 1) and \ + test(exp_polar(-I*pi/2), -I, 1) and \ + test(exp_polar(I*pi), -1, I) and \ + test(exp_polar(-I*pi), -1, -I) + + +def test_li(): + z = Symbol("z") + zr = Symbol("z", real=True) + zp = Symbol("z", positive=True) + zn = Symbol("z", negative=True) + + assert li(0) is S.Zero + assert li(1) is -oo + assert li(oo) is oo + + assert isinstance(li(z), li) + assert unchanged(li, -zp) + assert unchanged(li, zn) + + assert diff(li(z), z) == 1/log(z) + + assert conjugate(li(z)) == li(conjugate(z)) + assert conjugate(li(-zr)) == li(-zr) + assert unchanged(conjugate, li(-zp)) + assert unchanged(conjugate, li(zn)) + + assert li(z).rewrite(Li) == Li(z) + li(2) + assert li(z).rewrite(Ei) == Ei(log(z)) + assert li(z).rewrite(uppergamma) == (-log(1/log(z))/2 - log(-log(z)) + + log(log(z))/2 - expint(1, -log(z))) + assert li(z).rewrite(Si) == (-log(I*log(z)) - log(1/log(z))/2 + + log(log(z))/2 + Ci(I*log(z)) + Shi(log(z))) + assert li(z).rewrite(Ci) == (-log(I*log(z)) - log(1/log(z))/2 + + log(log(z))/2 + Ci(I*log(z)) + Shi(log(z))) + assert li(z).rewrite(Shi) == (-log(1/log(z))/2 + log(log(z))/2 + + Chi(log(z)) - Shi(log(z))) + assert li(z).rewrite(Chi) == (-log(1/log(z))/2 + log(log(z))/2 + + Chi(log(z)) - Shi(log(z))) + assert li(z).rewrite(hyper) ==(log(z)*hyper((1, 1), (2, 2), log(z)) - + log(1/log(z))/2 + log(log(z))/2 + EulerGamma) + assert li(z).rewrite(meijerg) == (-log(1/log(z))/2 - log(-log(z)) + log(log(z))/2 - + meijerg(((), (1,)), ((0, 0), ()), -log(z))) + + assert gruntz(1/li(z), z, oo) is S.Zero + assert li(z).series(z) == log(z)**5/600 + log(z)**4/96 + log(z)**3/18 + log(z)**2/4 + \ + log(z) + log(log(z)) + EulerGamma + raises(ArgumentIndexError, lambda: li(z).fdiff(2)) + + +def test_Li(): + assert Li(2) is S.Zero + assert Li(oo) is oo + + assert isinstance(Li(z), Li) + + assert diff(Li(z), z) == 1/log(z) + + assert gruntz(1/Li(z), z, oo) is S.Zero + assert Li(z).rewrite(li) == li(z) - li(2) + assert Li(z).series(z) == \ + log(z)**5/600 + log(z)**4/96 + log(z)**3/18 + log(z)**2/4 + log(z) + log(log(z)) - li(2) + EulerGamma + raises(ArgumentIndexError, lambda: Li(z).fdiff(2)) + + +def test_si(): + assert Si(I*x) == I*Shi(x) + assert Shi(I*x) == I*Si(x) + assert Si(-I*x) == -I*Shi(x) + assert Shi(-I*x) == -I*Si(x) + assert Si(-x) == -Si(x) + assert Shi(-x) == -Shi(x) + assert Si(exp_polar(2*pi*I)*x) == Si(x) + assert Si(exp_polar(-2*pi*I)*x) == Si(x) + assert Shi(exp_polar(2*pi*I)*x) == Shi(x) + assert Shi(exp_polar(-2*pi*I)*x) == Shi(x) + + assert Si(oo) == pi/2 + assert Si(-oo) == -pi/2 + assert Shi(oo) is oo + assert Shi(-oo) is -oo + + assert mytd(Si(x), sin(x)/x, x) + assert mytd(Shi(x), sinh(x)/x, x) + + assert mytn(Si(x), Si(x).rewrite(Ei), + -I*(-Ei(x*exp_polar(-I*pi/2))/2 + + Ei(x*exp_polar(I*pi/2))/2 - I*pi) + pi/2, x) + assert mytn(Si(x), Si(x).rewrite(expint), + -I*(-expint(1, x*exp_polar(-I*pi/2))/2 + + expint(1, x*exp_polar(I*pi/2))/2) + pi/2, x) + assert mytn(Shi(x), Shi(x).rewrite(Ei), + Ei(x)/2 - Ei(x*exp_polar(I*pi))/2 + I*pi/2, x) + assert mytn(Shi(x), Shi(x).rewrite(expint), + expint(1, x)/2 - expint(1, x*exp_polar(I*pi))/2 - I*pi/2, x) + + assert tn_arg(Si) + assert tn_arg(Shi) + + assert Si(x)._eval_as_leading_term(x, None, 1) == x + assert Si(2*x)._eval_as_leading_term(x, None, 1) == 2*x + assert Si(sin(x))._eval_as_leading_term(x, None, 1) == x + assert Si(x + 1)._eval_as_leading_term(x, None, 1) == Si(1) + assert Si(1/x)._eval_as_leading_term(x, None, 1) == \ + Si(1/x)._eval_as_leading_term(x, None, -1) == Si(1/x) + + assert Si(x).nseries(x, n=8) == \ + x - x**3/18 + x**5/600 - x**7/35280 + O(x**8) + assert Shi(x).nseries(x, n=8) == \ + x + x**3/18 + x**5/600 + x**7/35280 + O(x**8) + assert Si(sin(x)).nseries(x, n=5) == x - 2*x**3/9 + O(x**5) + assert Si(x).nseries(x, 1, n=3) == \ + Si(1) + (x - 1)*sin(1) + (x - 1)**2*(-sin(1)/2 + cos(1)/2) + O((x - 1)**3, (x, 1)) + + assert Si(x).series(x, oo) == -sin(x)*(-6/x**4 + x**(-2) + O(x**(-6), (x, oo))) - \ + cos(x)*(24/x**5 - 2/x**3 + 1/x + O(x**(-6), (x, oo))) + pi/2 + + t = Symbol('t', Dummy=True) + assert Si(x).rewrite(sinc).dummy_eq(Integral(sinc(t), (t, 0, x))) + + assert limit(Shi(x), x, S.Infinity) == S.Infinity + assert limit(Shi(x), x, S.NegativeInfinity) == S.NegativeInfinity + + +def test_ci(): + m1 = exp_polar(I*pi) + m1_ = exp_polar(-I*pi) + pI = exp_polar(I*pi/2) + mI = exp_polar(-I*pi/2) + + assert Ci(m1*x) == Ci(x) + I*pi + assert Ci(m1_*x) == Ci(x) - I*pi + assert Ci(pI*x) == Chi(x) + I*pi/2 + assert Ci(mI*x) == Chi(x) - I*pi/2 + assert Chi(m1*x) == Chi(x) + I*pi + assert Chi(m1_*x) == Chi(x) - I*pi + assert Chi(pI*x) == Ci(x) + I*pi/2 + assert Chi(mI*x) == Ci(x) - I*pi/2 + assert Ci(exp_polar(2*I*pi)*x) == Ci(x) + 2*I*pi + assert Chi(exp_polar(-2*I*pi)*x) == Chi(x) - 2*I*pi + assert Chi(exp_polar(2*I*pi)*x) == Chi(x) + 2*I*pi + assert Ci(exp_polar(-2*I*pi)*x) == Ci(x) - 2*I*pi + + assert Ci(oo) is S.Zero + assert Ci(-oo) == I*pi + assert Chi(oo) is oo + assert Chi(-oo) is oo + + assert mytd(Ci(x), cos(x)/x, x) + assert mytd(Chi(x), cosh(x)/x, x) + + assert mytn(Ci(x), Ci(x).rewrite(Ei), + Ei(x*exp_polar(-I*pi/2))/2 + Ei(x*exp_polar(I*pi/2))/2, x) + assert mytn(Chi(x), Chi(x).rewrite(Ei), + Ei(x)/2 + Ei(x*exp_polar(I*pi))/2 - I*pi/2, x) + + assert tn_arg(Ci) + assert tn_arg(Chi) + + assert Ci(x).nseries(x, n=4) == \ + EulerGamma + log(x) - x**2/4 + O(x**4) + assert Chi(x).nseries(x, n=4) == \ + EulerGamma + log(x) + x**2/4 + O(x**4) + + assert Ci(x).series(x, oo) == -cos(x)*(-6/x**4 + x**(-2) + O(x**(-6), (x, oo))) + \ + sin(x)*(24/x**5 - 2/x**3 + 1/x + O(x**(-6), (x, oo))) + + assert Ci(x).series(x, -oo) == -cos(x)*(-6/x**4 + x**(-2) + O(x**(-6), (x, -oo))) + \ + sin(x)*(24/x**5 - 2/x**3 + 1/x + O(x**(-6), (x, -oo))) + I*pi + + assert limit(log(x) - Ci(2*x), x, 0) == -log(2) - EulerGamma + assert Ci(x).rewrite(uppergamma) == -expint(1, x*exp_polar(-I*pi/2))/2 -\ + expint(1, x*exp_polar(I*pi/2))/2 + assert Ci(x).rewrite(expint) == -expint(1, x*exp_polar(-I*pi/2))/2 -\ + expint(1, x*exp_polar(I*pi/2))/2 + raises(ArgumentIndexError, lambda: Ci(x).fdiff(2)) + + +def test_fresnel(): + assert fresnels(0) is S.Zero + assert fresnels(oo) is S.Half + assert fresnels(-oo) == Rational(-1, 2) + assert fresnels(I*oo) == -I*S.Half + + assert unchanged(fresnels, z) + assert fresnels(-z) == -fresnels(z) + assert fresnels(I*z) == -I*fresnels(z) + assert fresnels(-I*z) == I*fresnels(z) + + assert conjugate(fresnels(z)) == fresnels(conjugate(z)) + + assert fresnels(z).diff(z) == sin(pi*z**2/2) + + assert fresnels(z).rewrite(erf) == (S.One + I)/4 * ( + erf((S.One + I)/2*sqrt(pi)*z) - I*erf((S.One - I)/2*sqrt(pi)*z)) + + assert fresnels(z).rewrite(hyper) == \ + pi*z**3/6 * hyper([Rational(3, 4)], [Rational(3, 2), Rational(7, 4)], -pi**2*z**4/16) + + assert fresnels(z).series(z, n=15) == \ + pi*z**3/6 - pi**3*z**7/336 + pi**5*z**11/42240 + O(z**15) + + assert fresnels(w).is_extended_real is True + assert fresnels(w).is_finite is True + + assert fresnels(z).is_extended_real is None + assert fresnels(z).is_finite is None + + assert fresnels(z).as_real_imag() == (fresnels(re(z) - I*im(z))/2 + + fresnels(re(z) + I*im(z))/2, + -I*(-fresnels(re(z) - I*im(z)) + fresnels(re(z) + I*im(z)))/2) + + assert fresnels(z).as_real_imag(deep=False) == (fresnels(re(z) - I*im(z))/2 + + fresnels(re(z) + I*im(z))/2, + -I*(-fresnels(re(z) - I*im(z)) + fresnels(re(z) + I*im(z)))/2) + + assert fresnels(w).as_real_imag() == (fresnels(w), 0) + assert fresnels(w).as_real_imag(deep=True) == (fresnels(w), 0) + + assert fresnels(2 + 3*I).as_real_imag() == ( + fresnels(2 + 3*I)/2 + fresnels(2 - 3*I)/2, + -I*(fresnels(2 + 3*I) - fresnels(2 - 3*I))/2 + ) + + assert expand_func(integrate(fresnels(z), z)) == \ + z*fresnels(z) + cos(pi*z**2/2)/pi + + assert fresnels(z).rewrite(meijerg) == sqrt(2)*pi*z**Rational(9, 4) * \ + meijerg(((), (1,)), ((Rational(3, 4),), + (Rational(1, 4), 0)), -pi**2*z**4/16)/(2*(-z)**Rational(3, 4)*(z**2)**Rational(3, 4)) + + assert fresnelc(0) is S.Zero + assert fresnelc(oo) == S.Half + assert fresnelc(-oo) == Rational(-1, 2) + assert fresnelc(I*oo) == I*S.Half + + assert unchanged(fresnelc, z) + assert fresnelc(-z) == -fresnelc(z) + assert fresnelc(I*z) == I*fresnelc(z) + assert fresnelc(-I*z) == -I*fresnelc(z) + + assert conjugate(fresnelc(z)) == fresnelc(conjugate(z)) + + assert fresnelc(z).diff(z) == cos(pi*z**2/2) + + assert fresnelc(z).rewrite(erf) == (S.One - I)/4 * ( + erf((S.One + I)/2*sqrt(pi)*z) + I*erf((S.One - I)/2*sqrt(pi)*z)) + + assert fresnelc(z).rewrite(hyper) == \ + z * hyper([Rational(1, 4)], [S.Half, Rational(5, 4)], -pi**2*z**4/16) + + assert fresnelc(w).is_extended_real is True + + assert fresnelc(z).as_real_imag() == \ + (fresnelc(re(z) - I*im(z))/2 + fresnelc(re(z) + I*im(z))/2, + -I*(-fresnelc(re(z) - I*im(z)) + fresnelc(re(z) + I*im(z)))/2) + + assert fresnelc(z).as_real_imag(deep=False) == \ + (fresnelc(re(z) - I*im(z))/2 + fresnelc(re(z) + I*im(z))/2, + -I*(-fresnelc(re(z) - I*im(z)) + fresnelc(re(z) + I*im(z)))/2) + + assert fresnelc(2 + 3*I).as_real_imag() == ( + fresnelc(2 - 3*I)/2 + fresnelc(2 + 3*I)/2, + -I*(fresnelc(2 + 3*I) - fresnelc(2 - 3*I))/2 + ) + + assert expand_func(integrate(fresnelc(z), z)) == \ + z*fresnelc(z) - sin(pi*z**2/2)/pi + + assert fresnelc(z).rewrite(meijerg) == sqrt(2)*pi*z**Rational(3, 4) * \ + meijerg(((), (1,)), ((Rational(1, 4),), + (Rational(3, 4), 0)), -pi**2*z**4/16)/(2*(-z)**Rational(1, 4)*(z**2)**Rational(1, 4)) + + from sympy.core.random import verify_numerically + + verify_numerically(re(fresnels(z)), fresnels(z).as_real_imag()[0], z) + verify_numerically(im(fresnels(z)), fresnels(z).as_real_imag()[1], z) + verify_numerically(fresnels(z), fresnels(z).rewrite(hyper), z) + verify_numerically(fresnels(z), fresnels(z).rewrite(meijerg), z) + + verify_numerically(re(fresnelc(z)), fresnelc(z).as_real_imag()[0], z) + verify_numerically(im(fresnelc(z)), fresnelc(z).as_real_imag()[1], z) + verify_numerically(fresnelc(z), fresnelc(z).rewrite(hyper), z) + verify_numerically(fresnelc(z), fresnelc(z).rewrite(meijerg), z) + + raises(ArgumentIndexError, lambda: fresnels(z).fdiff(2)) + raises(ArgumentIndexError, lambda: fresnelc(z).fdiff(2)) + + assert fresnels(x).taylor_term(-1, x) is S.Zero + assert fresnelc(x).taylor_term(-1, x) is S.Zero + assert fresnelc(x).taylor_term(1, x) == -pi**2*x**5/40 + + +def test_fresnel_series(): + assert fresnelc(z).series(z, n=15) == \ + z - pi**2*z**5/40 + pi**4*z**9/3456 - pi**6*z**13/599040 + O(z**15) + + # issues 6510, 10102 + fs = (S.Half - sin(pi*z**2/2)/(pi**2*z**3) + + (-1/(pi*z) + 3/(pi**3*z**5))*cos(pi*z**2/2)) + fc = (S.Half - cos(pi*z**2/2)/(pi**2*z**3) + + (1/(pi*z) - 3/(pi**3*z**5))*sin(pi*z**2/2)) + assert fresnels(z).series(z, oo) == fs + O(z**(-6), (z, oo)) + assert fresnelc(z).series(z, oo) == fc + O(z**(-6), (z, oo)) + assert (fresnels(z).series(z, -oo) + fs.subs(z, -z)).expand().is_Order + assert (fresnelc(z).series(z, -oo) + fc.subs(z, -z)).expand().is_Order + assert (fresnels(1/z).series(z) - fs.subs(z, 1/z)).expand().is_Order + assert (fresnelc(1/z).series(z) - fc.subs(z, 1/z)).expand().is_Order + assert ((2*fresnels(3*z)).series(z, oo) - 2*fs.subs(z, 3*z)).expand().is_Order + assert ((3*fresnelc(2*z)).series(z, oo) - 3*fc.subs(z, 2*z)).expand().is_Order + + +def test_integral_rewrites(): #issues 26134, 26144, 26306 + assert expint(n, x).rewrite(Integral).dummy_eq(Integral(t**-n * exp(-t*x), (t, 1, oo))) + assert Si(x).rewrite(Integral).dummy_eq(Integral(sinc(t), (t, 0, x))) + assert Ci(x).rewrite(Integral).dummy_eq(log(x) - Integral((1 - cos(t))/t, (t, 0, x)) + EulerGamma) + assert fresnels(x).rewrite(Integral).dummy_eq(Integral(sin(pi*t**2/2), (t, 0, x))) + assert fresnelc(x).rewrite(Integral).dummy_eq(Integral(cos(pi*t**2/2), (t, 0, x))) + assert Ei(x).rewrite(Integral).dummy_eq(Integral(exp(t)/t, (t, -oo, x))) + assert fresnels(x).diff(x) == fresnels(x).rewrite(Integral).diff(x) + assert fresnelc(x).diff(x) == fresnelc(x).rewrite(Integral).diff(x) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_gamma_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_gamma_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..14c57a31ce2edaa60fd5efc8bcbc95668961fd41 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_gamma_functions.py @@ -0,0 +1,741 @@ +from sympy.core.function import expand_func, Subs +from sympy.core import EulerGamma +from sympy.core.numbers import (I, Rational, nan, oo, pi, zoo) +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, Symbol) +from sympy.functions.combinatorial.factorials import factorial +from sympy.functions.combinatorial.numbers import harmonic +from sympy.functions.elementary.complexes import (Abs, conjugate, im, re) +from sympy.functions.elementary.exponential import (exp, exp_polar, log) +from sympy.functions.elementary.hyperbolic import tanh +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (cos, sin, atan) +from sympy.functions.special.error_functions import (Ei, erf, erfc) +from sympy.functions.special.gamma_functions import (digamma, gamma, loggamma, lowergamma, multigamma, polygamma, trigamma, uppergamma) +from sympy.functions.special.zeta_functions import zeta +from sympy.series.order import O + +from sympy.core.expr import unchanged +from sympy.core.function import ArgumentIndexError +from sympy.testing.pytest import raises +from sympy.core.random import (test_derivative_numerically as td, + random_complex_number as randcplx, + verify_numerically as tn) + +x = Symbol('x') +y = Symbol('y') +n = Symbol('n', integer=True) +w = Symbol('w', real=True) + +def test_gamma(): + assert gamma(nan) is nan + assert gamma(oo) is oo + + assert gamma(-100) is zoo + assert gamma(0) is zoo + assert gamma(-100.0) is zoo + + assert gamma(1) == 1 + assert gamma(2) == 1 + assert gamma(3) == 2 + + assert gamma(102) == factorial(101) + + assert gamma(S.Half) == sqrt(pi) + + assert gamma(Rational(3, 2)) == sqrt(pi)*S.Half + assert gamma(Rational(5, 2)) == sqrt(pi)*Rational(3, 4) + assert gamma(Rational(7, 2)) == sqrt(pi)*Rational(15, 8) + + assert gamma(Rational(-1, 2)) == -2*sqrt(pi) + assert gamma(Rational(-3, 2)) == sqrt(pi)*Rational(4, 3) + assert gamma(Rational(-5, 2)) == sqrt(pi)*Rational(-8, 15) + + assert gamma(Rational(-15, 2)) == sqrt(pi)*Rational(256, 2027025) + + assert gamma(Rational( + -11, 8)).expand(func=True) == Rational(64, 33)*gamma(Rational(5, 8)) + assert gamma(Rational( + -10, 3)).expand(func=True) == Rational(81, 280)*gamma(Rational(2, 3)) + assert gamma(Rational( + 14, 3)).expand(func=True) == Rational(880, 81)*gamma(Rational(2, 3)) + assert gamma(Rational( + 17, 7)).expand(func=True) == Rational(30, 49)*gamma(Rational(3, 7)) + assert gamma(Rational( + 19, 8)).expand(func=True) == Rational(33, 64)*gamma(Rational(3, 8)) + + assert gamma(x).diff(x) == gamma(x)*polygamma(0, x) + + assert gamma(x - 1).expand(func=True) == gamma(x)/(x - 1) + assert gamma(x + 2).expand(func=True, mul=False) == x*(x + 1)*gamma(x) + + assert conjugate(gamma(x)) == gamma(conjugate(x)) + + assert expand_func(gamma(x + Rational(3, 2))) == \ + (x + S.Half)*gamma(x + S.Half) + + assert expand_func(gamma(x - S.Half)) == \ + gamma(S.Half + x)/(x - S.Half) + + # Test a bug: + assert expand_func(gamma(x + Rational(3, 4))) == gamma(x + Rational(3, 4)) + + # XXX: Not sure about these tests. I can fix them by defining e.g. + # exp_polar.is_integer but I'm not sure if that makes sense. + assert gamma(3*exp_polar(I*pi)/4).is_nonnegative is False + assert gamma(3*exp_polar(I*pi)/4).is_extended_nonpositive is True + + y = Symbol('y', nonpositive=True, integer=True) + assert gamma(y).is_real == False + y = Symbol('y', positive=True, noninteger=True) + assert gamma(y).is_real == True + + assert gamma(-1.0, evaluate=False).is_real == False + assert gamma(0, evaluate=False).is_real == False + assert gamma(-2, evaluate=False).is_real == False + + +def test_gamma_rewrite(): + assert gamma(n).rewrite(factorial) == factorial(n - 1) + + +def test_gamma_series(): + assert gamma(x + 1).series(x, 0, 3) == \ + 1 - EulerGamma*x + x**2*(EulerGamma**2/2 + pi**2/12) + O(x**3) + assert gamma(x).series(x, -1, 3) == \ + -1/(x + 1) + EulerGamma - 1 + (x + 1)*(-1 - pi**2/12 - EulerGamma**2/2 + \ + EulerGamma) + (x + 1)**2*(-1 - pi**2/12 - EulerGamma**2/2 + EulerGamma**3/6 - \ + polygamma(2, 1)/6 + EulerGamma*pi**2/12 + EulerGamma) + O((x + 1)**3, (x, -1)) + + +def tn_branch(s, func): + from sympy.core.random import uniform + c = uniform(1, 5) + expr = func(s, c*exp_polar(I*pi)) - func(s, c*exp_polar(-I*pi)) + eps = 1e-15 + expr2 = func(s + eps, -c + eps*I) - func(s + eps, -c - eps*I) + return abs(expr.n() - expr2.n()).n() < 1e-10 + + +def test_lowergamma(): + from sympy.functions.special.error_functions import expint + from sympy.functions.special.hyper import meijerg + assert lowergamma(x, 0) == 0 + assert lowergamma(x, y).diff(y) == y**(x - 1)*exp(-y) + assert td(lowergamma(randcplx(), y), y) + assert td(lowergamma(x, randcplx()), x) + assert lowergamma(x, y).diff(x) == \ + gamma(x)*digamma(x) - uppergamma(x, y)*log(y) \ + - meijerg([], [1, 1], [0, 0, x], [], y) + + assert lowergamma(S.Half, x) == sqrt(pi)*erf(sqrt(x)) + assert not lowergamma(S.Half - 3, x).has(lowergamma) + assert not lowergamma(S.Half + 3, x).has(lowergamma) + assert lowergamma(S.Half, x, evaluate=False).has(lowergamma) + assert tn(lowergamma(S.Half + 3, x, evaluate=False), + lowergamma(S.Half + 3, x), x) + assert tn(lowergamma(S.Half - 3, x, evaluate=False), + lowergamma(S.Half - 3, x), x) + + assert tn_branch(-3, lowergamma) + assert tn_branch(-4, lowergamma) + assert tn_branch(Rational(1, 3), lowergamma) + assert tn_branch(pi, lowergamma) + assert lowergamma(3, exp_polar(4*pi*I)*x) == lowergamma(3, x) + assert lowergamma(y, exp_polar(5*pi*I)*x) == \ + exp(4*I*pi*y)*lowergamma(y, x*exp_polar(pi*I)) + assert lowergamma(-2, exp_polar(5*pi*I)*x) == \ + lowergamma(-2, x*exp_polar(I*pi)) + 2*pi*I + + assert conjugate(lowergamma(x, y)) == lowergamma(conjugate(x), conjugate(y)) + assert conjugate(lowergamma(x, 0)) == 0 + assert unchanged(conjugate, lowergamma(x, -oo)) + + assert lowergamma(0, x)._eval_is_meromorphic(x, 0) == False + assert lowergamma(S(1)/3, x)._eval_is_meromorphic(x, 0) == False + assert lowergamma(1, x, evaluate=False)._eval_is_meromorphic(x, 0) == True + assert lowergamma(x, x)._eval_is_meromorphic(x, 0) == False + assert lowergamma(x + 1, x)._eval_is_meromorphic(x, 0) == False + assert lowergamma(1/x, x)._eval_is_meromorphic(x, 0) == False + assert lowergamma(0, x + 1)._eval_is_meromorphic(x, 0) == False + assert lowergamma(S(1)/3, x + 1)._eval_is_meromorphic(x, 0) == True + assert lowergamma(1, x + 1, evaluate=False)._eval_is_meromorphic(x, 0) == True + assert lowergamma(x, x + 1)._eval_is_meromorphic(x, 0) == True + assert lowergamma(x + 1, x + 1)._eval_is_meromorphic(x, 0) == True + assert lowergamma(1/x, x + 1)._eval_is_meromorphic(x, 0) == False + assert lowergamma(0, 1/x)._eval_is_meromorphic(x, 0) == False + assert lowergamma(S(1)/3, 1/x)._eval_is_meromorphic(x, 0) == False + assert lowergamma(1, 1/x, evaluate=False)._eval_is_meromorphic(x, 0) == False + assert lowergamma(x, 1/x)._eval_is_meromorphic(x, 0) == False + assert lowergamma(x + 1, 1/x)._eval_is_meromorphic(x, 0) == False + assert lowergamma(1/x, 1/x)._eval_is_meromorphic(x, 0) == False + + assert lowergamma(x, 2).series(x, oo, 3) == \ + 2**x*(1 + 2/(x + 1))*exp(-2)/x + O(exp(x*log(2))/x**3, (x, oo)) + + assert lowergamma( + x, y).rewrite(expint) == -y**x*expint(-x + 1, y) + gamma(x) + k = Symbol('k', integer=True) + assert lowergamma( + k, y).rewrite(expint) == -y**k*expint(-k + 1, y) + gamma(k) + k = Symbol('k', integer=True, positive=False) + assert lowergamma(k, y).rewrite(expint) == lowergamma(k, y) + assert lowergamma(x, y).rewrite(uppergamma) == gamma(x) - uppergamma(x, y) + + assert lowergamma(70, 6) == factorial(69) - 69035724522603011058660187038367026272747334489677105069435923032634389419656200387949342530805432320 * exp(-6) + assert (lowergamma(S(77) / 2, 6) - lowergamma(S(77) / 2, 6, evaluate=False)).evalf() < 1e-16 + assert (lowergamma(-S(77) / 2, 6) - lowergamma(-S(77) / 2, 6, evaluate=False)).evalf() < 1e-16 + + +def test_uppergamma(): + from sympy.functions.special.error_functions import expint + from sympy.functions.special.hyper import meijerg + assert uppergamma(4, 0) == 6 + assert uppergamma(x, y).diff(y) == -y**(x - 1)*exp(-y) + assert td(uppergamma(randcplx(), y), y) + assert uppergamma(x, y).diff(x) == \ + uppergamma(x, y)*log(y) + meijerg([], [1, 1], [0, 0, x], [], y) + assert td(uppergamma(x, randcplx()), x) + + p = Symbol('p', positive=True) + assert uppergamma(0, p) == -Ei(-p) + assert uppergamma(p, 0) == gamma(p) + assert uppergamma(S.Half, x) == sqrt(pi)*erfc(sqrt(x)) + assert not uppergamma(S.Half - 3, x).has(uppergamma) + assert not uppergamma(S.Half + 3, x).has(uppergamma) + assert uppergamma(S.Half, x, evaluate=False).has(uppergamma) + assert tn(uppergamma(S.Half + 3, x, evaluate=False), + uppergamma(S.Half + 3, x), x) + assert tn(uppergamma(S.Half - 3, x, evaluate=False), + uppergamma(S.Half - 3, x), x) + + assert unchanged(uppergamma, x, -oo) + assert unchanged(uppergamma, x, 0) + + assert tn_branch(-3, uppergamma) + assert tn_branch(-4, uppergamma) + assert tn_branch(Rational(1, 3), uppergamma) + assert tn_branch(pi, uppergamma) + assert uppergamma(3, exp_polar(4*pi*I)*x) == uppergamma(3, x) + assert uppergamma(y, exp_polar(5*pi*I)*x) == \ + exp(4*I*pi*y)*uppergamma(y, x*exp_polar(pi*I)) + \ + gamma(y)*(1 - exp(4*pi*I*y)) + assert uppergamma(-2, exp_polar(5*pi*I)*x) == \ + uppergamma(-2, x*exp_polar(I*pi)) - 2*pi*I + + assert uppergamma(-2, x) == expint(3, x)/x**2 + + assert conjugate(uppergamma(x, y)) == uppergamma(conjugate(x), conjugate(y)) + assert unchanged(conjugate, uppergamma(x, -oo)) + + assert uppergamma(x, y).rewrite(expint) == y**x*expint(-x + 1, y) + assert uppergamma(x, y).rewrite(lowergamma) == gamma(x) - lowergamma(x, y) + + assert uppergamma(70, 6) == 69035724522603011058660187038367026272747334489677105069435923032634389419656200387949342530805432320*exp(-6) + assert (uppergamma(S(77) / 2, 6) - uppergamma(S(77) / 2, 6, evaluate=False)).evalf() < 1e-16 + assert (uppergamma(-S(77) / 2, 6) - uppergamma(-S(77) / 2, 6, evaluate=False)).evalf() < 1e-16 + + +def test_polygamma(): + assert polygamma(n, nan) is nan + + assert polygamma(0, oo) is oo + assert polygamma(0, -oo) is oo + assert polygamma(0, I*oo) is oo + assert polygamma(0, -I*oo) is oo + assert polygamma(1, oo) == 0 + assert polygamma(5, oo) == 0 + + assert polygamma(0, -9) is zoo + + assert polygamma(0, -9) is zoo + assert polygamma(0, -1) is zoo + assert polygamma(Rational(3, 2), -1) is zoo + + assert polygamma(0, 0) is zoo + + assert polygamma(0, 1) == -EulerGamma + assert polygamma(0, 7) == Rational(49, 20) - EulerGamma + + assert polygamma(1, 1) == pi**2/6 + assert polygamma(1, 2) == pi**2/6 - 1 + assert polygamma(1, 3) == pi**2/6 - Rational(5, 4) + assert polygamma(3, 1) == pi**4 / 15 + assert polygamma(3, 5) == 6*(Rational(-22369, 20736) + pi**4/90) + assert polygamma(5, 1) == 8 * pi**6 / 63 + + assert polygamma(1, S.Half) == pi**2 / 2 + assert polygamma(2, S.Half) == -14*zeta(3) + assert polygamma(11, S.Half) == 176896*pi**12 + + def t(m, n): + x = S(m)/n + r = polygamma(0, x) + if r.has(polygamma): + return False + return abs(polygamma(0, x.n()).n() - r.n()).n() < 1e-10 + assert t(1, 2) + assert t(3, 2) + assert t(-1, 2) + assert t(1, 4) + assert t(-3, 4) + assert t(1, 3) + assert t(4, 3) + assert t(3, 4) + assert t(2, 3) + assert t(123, 5) + + assert polygamma(0, x).rewrite(zeta) == polygamma(0, x) + assert polygamma(1, x).rewrite(zeta) == zeta(2, x) + assert polygamma(2, x).rewrite(zeta) == -2*zeta(3, x) + assert polygamma(I, 2).rewrite(zeta) == polygamma(I, 2) + n1 = Symbol('n1') + n2 = Symbol('n2', real=True) + n3 = Symbol('n3', integer=True) + n4 = Symbol('n4', positive=True) + n5 = Symbol('n5', positive=True, integer=True) + assert polygamma(n1, x).rewrite(zeta) == polygamma(n1, x) + assert polygamma(n2, x).rewrite(zeta) == polygamma(n2, x) + assert polygamma(n3, x).rewrite(zeta) == polygamma(n3, x) + assert polygamma(n4, x).rewrite(zeta) == polygamma(n4, x) + assert polygamma(n5, x).rewrite(zeta) == (-1)**(n5 + 1) * factorial(n5) * zeta(n5 + 1, x) + + assert polygamma(3, 7*x).diff(x) == 7*polygamma(4, 7*x) + + assert polygamma(0, x).rewrite(harmonic) == harmonic(x - 1) - EulerGamma + assert polygamma(2, x).rewrite(harmonic) == 2*harmonic(x - 1, 3) - 2*zeta(3) + ni = Symbol("n", integer=True) + assert polygamma(ni, x).rewrite(harmonic) == (-1)**(ni + 1)*(-harmonic(x - 1, ni + 1) + + zeta(ni + 1))*factorial(ni) + + # Polygamma of non-negative integer order is unbranched: + k = Symbol('n', integer=True, nonnegative=True) + assert polygamma(k, exp_polar(2*I*pi)*x) == polygamma(k, x) + + # but negative integers are branched! + k = Symbol('n', integer=True) + assert polygamma(k, exp_polar(2*I*pi)*x).args == (k, exp_polar(2*I*pi)*x) + + # Polygamma of order -1 is loggamma: + assert polygamma(-1, x) == loggamma(x) - log(2*pi) / 2 + + # But smaller orders are iterated integrals and don't have a special name + assert polygamma(-2, x).func is polygamma + + # Test a bug + assert polygamma(0, -x).expand(func=True) == polygamma(0, -x) + + assert polygamma(2, 2.5).is_positive == False + assert polygamma(2, -2.5).is_positive == False + assert polygamma(3, 2.5).is_positive == True + assert polygamma(3, -2.5).is_positive is True + assert polygamma(-2, -2.5).is_positive is None + assert polygamma(-3, -2.5).is_positive is None + + assert polygamma(2, 2.5).is_negative == True + assert polygamma(3, 2.5).is_negative == False + assert polygamma(3, -2.5).is_negative == False + assert polygamma(2, -2.5).is_negative is True + assert polygamma(-2, -2.5).is_negative is None + assert polygamma(-3, -2.5).is_negative is None + + assert polygamma(I, 2).is_positive is None + assert polygamma(I, 3).is_negative is None + + # issue 17350 + assert (I*polygamma(I, pi)).as_real_imag() == \ + (-im(polygamma(I, pi)), re(polygamma(I, pi))) + assert (tanh(polygamma(I, 1))).rewrite(exp) == \ + (exp(polygamma(I, 1)) - exp(-polygamma(I, 1)))/(exp(polygamma(I, 1)) + exp(-polygamma(I, 1))) + assert (I / polygamma(I, 4)).rewrite(exp) == \ + I*exp(-I*atan(im(polygamma(I, 4))/re(polygamma(I, 4))))/Abs(polygamma(I, 4)) + + # issue 12569 + assert unchanged(im, polygamma(0, I)) + assert polygamma(Symbol('a', positive=True), Symbol('b', positive=True)).is_real is True + assert polygamma(0, I).is_real is None + + assert str(polygamma(pi, 3).evalf(n=10)) == "0.1169314564" + assert str(polygamma(2.3, 1.0).evalf(n=10)) == "-3.003302909" + assert str(polygamma(-1, 1).evalf(n=10)) == "-0.9189385332" # not zero + assert str(polygamma(I, 1).evalf(n=10)) == "-3.109856569 + 1.89089016*I" + assert str(polygamma(1, I).evalf(n=10)) == "-0.5369999034 - 0.7942335428*I" + assert str(polygamma(I, I).evalf(n=10)) == "6.332362889 + 45.92828268*I" + + +def test_polygamma_expand_func(): + assert polygamma(0, x).expand(func=True) == polygamma(0, x) + assert polygamma(0, 2*x).expand(func=True) == \ + polygamma(0, x)/2 + polygamma(0, S.Half + x)/2 + log(2) + assert polygamma(1, 2*x).expand(func=True) == \ + polygamma(1, x)/4 + polygamma(1, S.Half + x)/4 + assert polygamma(2, x).expand(func=True) == \ + polygamma(2, x) + assert polygamma(0, -1 + x).expand(func=True) == \ + polygamma(0, x) - 1/(x - 1) + assert polygamma(0, 1 + x).expand(func=True) == \ + 1/x + polygamma(0, x ) + assert polygamma(0, 2 + x).expand(func=True) == \ + 1/x + 1/(1 + x) + polygamma(0, x) + assert polygamma(0, 3 + x).expand(func=True) == \ + polygamma(0, x) + 1/x + 1/(1 + x) + 1/(2 + x) + assert polygamma(0, 4 + x).expand(func=True) == \ + polygamma(0, x) + 1/x + 1/(1 + x) + 1/(2 + x) + 1/(3 + x) + assert polygamma(1, 1 + x).expand(func=True) == \ + polygamma(1, x) - 1/x**2 + assert polygamma(1, 2 + x).expand(func=True, multinomial=False) == \ + polygamma(1, x) - 1/x**2 - 1/(1 + x)**2 + assert polygamma(1, 3 + x).expand(func=True, multinomial=False) == \ + polygamma(1, x) - 1/x**2 - 1/(1 + x)**2 - 1/(2 + x)**2 + assert polygamma(1, 4 + x).expand(func=True, multinomial=False) == \ + polygamma(1, x) - 1/x**2 - 1/(1 + x)**2 - \ + 1/(2 + x)**2 - 1/(3 + x)**2 + assert polygamma(0, x + y).expand(func=True) == \ + polygamma(0, x + y) + assert polygamma(1, x + y).expand(func=True) == \ + polygamma(1, x + y) + assert polygamma(1, 3 + 4*x + y).expand(func=True, multinomial=False) == \ + polygamma(1, y + 4*x) - 1/(y + 4*x)**2 - \ + 1/(1 + y + 4*x)**2 - 1/(2 + y + 4*x)**2 + assert polygamma(3, 3 + 4*x + y).expand(func=True, multinomial=False) == \ + polygamma(3, y + 4*x) - 6/(y + 4*x)**4 - \ + 6/(1 + y + 4*x)**4 - 6/(2 + y + 4*x)**4 + assert polygamma(3, 4*x + y + 1).expand(func=True, multinomial=False) == \ + polygamma(3, y + 4*x) - 6/(y + 4*x)**4 + e = polygamma(3, 4*x + y + Rational(3, 2)) + assert e.expand(func=True) == e + e = polygamma(3, x + y + Rational(3, 4)) + assert e.expand(func=True, basic=False) == e + + assert polygamma(-1, x, evaluate=False).expand(func=True) == \ + loggamma(x) - log(pi)/2 - log(2)/2 + p2 = polygamma(-2, x).expand(func=True) + x**2/2 - x/2 + S(1)/12 + assert isinstance(p2, Subs) + assert p2.point == (-1,) + + +def test_digamma(): + assert digamma(nan) == nan + + assert digamma(oo) == oo + assert digamma(-oo) == oo + assert digamma(I*oo) == oo + assert digamma(-I*oo) == oo + + assert digamma(-9) == zoo + + assert digamma(-9) == zoo + assert digamma(-1) == zoo + + assert digamma(0) == zoo + + assert digamma(1) == -EulerGamma + assert digamma(7) == Rational(49, 20) - EulerGamma + + def t(m, n): + x = S(m)/n + r = digamma(x) + if r.has(digamma): + return False + return abs(digamma(x.n()).n() - r.n()).n() < 1e-10 + assert t(1, 2) + assert t(3, 2) + assert t(-1, 2) + assert t(1, 4) + assert t(-3, 4) + assert t(1, 3) + assert t(4, 3) + assert t(3, 4) + assert t(2, 3) + assert t(123, 5) + + assert digamma(x).rewrite(zeta) == polygamma(0, x) + + assert digamma(x).rewrite(harmonic) == harmonic(x - 1) - EulerGamma + + assert digamma(I).is_real is None + + assert digamma(x,evaluate=False).fdiff() == polygamma(1, x) + + assert digamma(x,evaluate=False).is_real is None + + assert digamma(x,evaluate=False).is_positive is None + + assert digamma(x,evaluate=False).is_negative is None + + assert digamma(x,evaluate=False).rewrite(polygamma) == polygamma(0, x) + + +def test_digamma_expand_func(): + assert digamma(x).expand(func=True) == polygamma(0, x) + assert digamma(2*x).expand(func=True) == \ + polygamma(0, x)/2 + polygamma(0, Rational(1, 2) + x)/2 + log(2) + assert digamma(-1 + x).expand(func=True) == \ + polygamma(0, x) - 1/(x - 1) + assert digamma(1 + x).expand(func=True) == \ + 1/x + polygamma(0, x ) + assert digamma(2 + x).expand(func=True) == \ + 1/x + 1/(1 + x) + polygamma(0, x) + assert digamma(3 + x).expand(func=True) == \ + polygamma(0, x) + 1/x + 1/(1 + x) + 1/(2 + x) + assert digamma(4 + x).expand(func=True) == \ + polygamma(0, x) + 1/x + 1/(1 + x) + 1/(2 + x) + 1/(3 + x) + assert digamma(x + y).expand(func=True) == \ + polygamma(0, x + y) + +def test_trigamma(): + assert trigamma(nan) == nan + + assert trigamma(oo) == 0 + + assert trigamma(1) == pi**2/6 + assert trigamma(2) == pi**2/6 - 1 + assert trigamma(3) == pi**2/6 - Rational(5, 4) + + assert trigamma(x, evaluate=False).rewrite(zeta) == zeta(2, x) + assert trigamma(x, evaluate=False).rewrite(harmonic) == \ + trigamma(x).rewrite(polygamma).rewrite(harmonic) + + assert trigamma(x,evaluate=False).fdiff() == polygamma(2, x) + + assert trigamma(x,evaluate=False).is_real is None + + assert trigamma(x,evaluate=False).is_positive is None + + assert trigamma(x,evaluate=False).is_negative is None + + assert trigamma(x,evaluate=False).rewrite(polygamma) == polygamma(1, x) + +def test_trigamma_expand_func(): + assert trigamma(2*x).expand(func=True) == \ + polygamma(1, x)/4 + polygamma(1, Rational(1, 2) + x)/4 + assert trigamma(1 + x).expand(func=True) == \ + polygamma(1, x) - 1/x**2 + assert trigamma(2 + x).expand(func=True, multinomial=False) == \ + polygamma(1, x) - 1/x**2 - 1/(1 + x)**2 + assert trigamma(3 + x).expand(func=True, multinomial=False) == \ + polygamma(1, x) - 1/x**2 - 1/(1 + x)**2 - 1/(2 + x)**2 + assert trigamma(4 + x).expand(func=True, multinomial=False) == \ + polygamma(1, x) - 1/x**2 - 1/(1 + x)**2 - \ + 1/(2 + x)**2 - 1/(3 + x)**2 + assert trigamma(x + y).expand(func=True) == \ + polygamma(1, x + y) + assert trigamma(3 + 4*x + y).expand(func=True, multinomial=False) == \ + polygamma(1, y + 4*x) - 1/(y + 4*x)**2 - \ + 1/(1 + y + 4*x)**2 - 1/(2 + y + 4*x)**2 + +def test_loggamma(): + raises(TypeError, lambda: loggamma(2, 3)) + raises(ArgumentIndexError, lambda: loggamma(x).fdiff(2)) + + assert loggamma(-1) is oo + assert loggamma(-2) is oo + assert loggamma(0) is oo + assert loggamma(1) == 0 + assert loggamma(2) == 0 + assert loggamma(3) == log(2) + assert loggamma(4) == log(6) + + n = Symbol("n", integer=True, positive=True) + assert loggamma(n) == log(gamma(n)) + assert loggamma(-n) is oo + assert loggamma(n/2) == log(2**(-n + 1)*sqrt(pi)*gamma(n)/gamma(n/2 + S.Half)) + + assert loggamma(oo) is oo + assert loggamma(-oo) is zoo + assert loggamma(I*oo) is zoo + assert loggamma(-I*oo) is zoo + assert loggamma(zoo) is zoo + assert loggamma(nan) is nan + + L = loggamma(Rational(16, 3)) + E = -5*log(3) + loggamma(Rational(1, 3)) + log(4) + log(7) + log(10) + log(13) + assert expand_func(L).doit() == E + assert L.n() == E.n() + + L = loggamma(Rational(19, 4)) + E = -4*log(4) + loggamma(Rational(3, 4)) + log(3) + log(7) + log(11) + log(15) + assert expand_func(L).doit() == E + assert L.n() == E.n() + + L = loggamma(Rational(23, 7)) + E = -3*log(7) + log(2) + loggamma(Rational(2, 7)) + log(9) + log(16) + assert expand_func(L).doit() == E + assert L.n() == E.n() + + L = loggamma(Rational(19, 4) - 7) + E = -log(9) - log(5) + loggamma(Rational(3, 4)) + 3*log(4) - 3*I*pi + assert expand_func(L).doit() == E + assert L.n() == E.n() + + L = loggamma(Rational(23, 7) - 6) + E = -log(19) - log(12) - log(5) + loggamma(Rational(2, 7)) + 3*log(7) - 3*I*pi + assert expand_func(L).doit() == E + assert L.n() == E.n() + + assert loggamma(x).diff(x) == polygamma(0, x) + s1 = loggamma(1/(x + sin(x)) + cos(x)).nseries(x, n=4) + s2 = (-log(2*x) - 1)/(2*x) - log(x/pi)/2 + (4 - log(2*x))*x/24 + O(x**2) + \ + log(x)*x**2/2 + assert (s1 - s2).expand(force=True).removeO() == 0 + s1 = loggamma(1/x).series(x) + s2 = (1/x - S.Half)*log(1/x) - 1/x + log(2*pi)/2 + \ + x/12 - x**3/360 + x**5/1260 + O(x**7) + assert ((s1 - s2).expand(force=True)).removeO() == 0 + + assert loggamma(x).rewrite('intractable') == log(gamma(x)) + + s1 = loggamma(x).series(x).cancel() + assert s1 == -log(x) - EulerGamma*x + pi**2*x**2/12 + x**3*polygamma(2, 1)/6 + \ + pi**4*x**4/360 + x**5*polygamma(4, 1)/120 + O(x**6) + assert s1 == loggamma(x).rewrite('intractable').series(x).cancel() + + assert conjugate(loggamma(x)) == loggamma(conjugate(x)) + assert conjugate(loggamma(0)) is oo + assert conjugate(loggamma(1)) == loggamma(conjugate(1)) + assert conjugate(loggamma(-oo)) == conjugate(zoo) + + assert loggamma(Symbol('v', positive=True)).is_real is True + assert loggamma(Symbol('v', zero=True)).is_real is False + assert loggamma(Symbol('v', negative=True)).is_real is False + assert loggamma(Symbol('v', nonpositive=True)).is_real is False + assert loggamma(Symbol('v', nonnegative=True)).is_real is None + assert loggamma(Symbol('v', imaginary=True)).is_real is None + assert loggamma(Symbol('v', real=True)).is_real is None + assert loggamma(Symbol('v')).is_real is None + + assert loggamma(S.Half).is_real is True + assert loggamma(0).is_real is False + assert loggamma(Rational(-1, 2)).is_real is False + assert loggamma(I).is_real is None + assert loggamma(2 + 3*I).is_real is None + + def tN(N, M): + assert loggamma(1/x)._eval_nseries(x, n=N).getn() == M + tN(0, 0) + tN(1, 1) + tN(2, 2) + tN(3, 3) + tN(4, 4) + tN(5, 5) + + +def test_polygamma_expansion(): + # A. & S., pa. 259 and 260 + assert polygamma(0, 1/x).nseries(x, n=3) == \ + -log(x) - x/2 - x**2/12 + O(x**3) + assert polygamma(1, 1/x).series(x, n=5) == \ + x + x**2/2 + x**3/6 + O(x**5) + assert polygamma(3, 1/x).nseries(x, n=11) == \ + 2*x**3 + 3*x**4 + 2*x**5 - x**7 + 4*x**9/3 + O(x**11) + + +def test_polygamma_leading_term(): + expr = -log(1/x) + polygamma(0, 1 + 1/x) + S.EulerGamma + assert expr.as_leading_term(x, logx=-y) == S.EulerGamma + + +def test_issue_8657(): + n = Symbol('n', negative=True, integer=True) + m = Symbol('m', integer=True) + o = Symbol('o', positive=True) + p = Symbol('p', negative=True, integer=False) + assert gamma(n).is_real is False + assert gamma(m).is_real is None + assert gamma(o).is_real is True + assert gamma(p).is_real is True + assert gamma(w).is_real is None + + +def test_issue_8524(): + x = Symbol('x', positive=True) + y = Symbol('y', negative=True) + z = Symbol('z', positive=False) + p = Symbol('p', negative=False) + q = Symbol('q', integer=True) + r = Symbol('r', integer=False) + e = Symbol('e', even=True, negative=True) + assert gamma(x).is_positive is True + assert gamma(y).is_positive is None + assert gamma(z).is_positive is None + assert gamma(p).is_positive is None + assert gamma(q).is_positive is None + assert gamma(r).is_positive is None + assert gamma(e + S.Half).is_positive is True + assert gamma(e - S.Half).is_positive is False + +def test_issue_14450(): + assert uppergamma(Rational(3, 8), x).evalf() == uppergamma(Rational(3, 8), x) + assert lowergamma(x, Rational(3, 8)).evalf() == lowergamma(x, Rational(3, 8)) + # some values from Wolfram Alpha for comparison + assert abs(uppergamma(Rational(3, 8), 2).evalf() - 0.07105675881) < 1e-9 + assert abs(lowergamma(Rational(3, 8), 2).evalf() - 2.2993794256) < 1e-9 + +def test_issue_14528(): + k = Symbol('k', integer=True, nonpositive=True) + assert isinstance(gamma(k), gamma) + +def test_multigamma(): + from sympy.concrete.products import Product + p = Symbol('p') + _k = Dummy('_k') + + assert multigamma(x, p).dummy_eq(pi**(p*(p - 1)/4)*\ + Product(gamma(x + (1 - _k)/2), (_k, 1, p))) + + assert conjugate(multigamma(x, p)).dummy_eq(pi**((conjugate(p) - 1)*\ + conjugate(p)/4)*Product(gamma(conjugate(x) + (1-conjugate(_k))/2), (_k, 1, p))) + assert conjugate(multigamma(x, 1)) == gamma(conjugate(x)) + + p = Symbol('p', positive=True) + assert conjugate(multigamma(x, p)).dummy_eq(pi**((p - 1)*p/4)*\ + Product(gamma(conjugate(x) + (1-conjugate(_k))/2), (_k, 1, p))) + + assert multigamma(nan, 1) is nan + assert multigamma(oo, 1).doit() is oo + + assert multigamma(1, 1) == 1 + assert multigamma(2, 1) == 1 + assert multigamma(3, 1) == 2 + + assert multigamma(102, 1) == factorial(101) + assert multigamma(S.Half, 1) == sqrt(pi) + + assert multigamma(1, 2) == pi + assert multigamma(2, 2) == pi/2 + + assert multigamma(1, 3) is zoo + assert multigamma(2, 3) == pi**2/2 + assert multigamma(3, 3) == 3*pi**2/2 + + assert multigamma(x, 1).diff(x) == gamma(x)*polygamma(0, x) + assert multigamma(x, 2).diff(x) == sqrt(pi)*gamma(x)*gamma(x - S.Half)*\ + polygamma(0, x) + sqrt(pi)*gamma(x)*gamma(x - S.Half)*polygamma(0, x - S.Half) + + assert multigamma(x - 1, 1).expand(func=True) == gamma(x)/(x - 1) + assert multigamma(x + 2, 1).expand(func=True, mul=False) == x*(x + 1)*\ + gamma(x) + assert multigamma(x - 1, 2).expand(func=True) == sqrt(pi)*gamma(x)*\ + gamma(x + S.Half)/(x**3 - 3*x**2 + x*Rational(11, 4) - Rational(3, 4)) + assert multigamma(x - 1, 3).expand(func=True) == pi**Rational(3, 2)*gamma(x)**2*\ + gamma(x + S.Half)/(x**5 - 6*x**4 + 55*x**3/4 - 15*x**2 + x*Rational(31, 4) - Rational(3, 2)) + + assert multigamma(n, 1).rewrite(factorial) == factorial(n - 1) + assert multigamma(n, 2).rewrite(factorial) == sqrt(pi)*\ + factorial(n - Rational(3, 2))*factorial(n - 1) + assert multigamma(n, 3).rewrite(factorial) == pi**Rational(3, 2)*\ + factorial(n - 2)*factorial(n - Rational(3, 2))*factorial(n - 1) + + assert multigamma(Rational(-1, 2), 3, evaluate=False).is_real == False + assert multigamma(S.Half, 3, evaluate=False).is_real == False + assert multigamma(0, 1, evaluate=False).is_real == False + assert multigamma(1, 3, evaluate=False).is_real == False + assert multigamma(-1.0, 3, evaluate=False).is_real == False + assert multigamma(0.7, 3, evaluate=False).is_real == True + assert multigamma(3, 3, evaluate=False).is_real == True + +def test_gamma_as_leading_term(): + assert gamma(x).as_leading_term(x) == 1/x + assert gamma(2 + x).as_leading_term(x) == S(1) + assert gamma(cos(x)).as_leading_term(x) == S(1) + assert gamma(sin(x)).as_leading_term(x) == 1/x diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_hyper.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_hyper.py new file mode 100644 index 0000000000000000000000000000000000000000..f1be5b5f0db158ff76173e180ed8d88bd59461b9 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_hyper.py @@ -0,0 +1,403 @@ +from sympy.core.containers import Tuple +from sympy.core.function import Derivative +from sympy.core.numbers import (I, Rational, oo, pi) +from sympy.core.singleton import S +from sympy.core.symbol import symbols +from sympy.functions.elementary.exponential import (exp, log) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import cos +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import (appellf1, hyper, meijerg) +from sympy.series.order import O +from sympy.abc import x, z, k +from sympy.series.limits import limit +from sympy.testing.pytest import raises, slow +from sympy.core.random import ( + random_complex_number as randcplx, + verify_numerically as tn, + test_derivative_numerically as td) + + +def test_TupleParametersBase(): + # test that our implementation of the chain rule works + p = hyper((), (), z**2) + assert p.diff(z) == p*2*z + + +def test_hyper(): + raises(TypeError, lambda: hyper(1, 2, z)) + + assert hyper((2, 1), (1,), z) == hyper(Tuple(1, 2), Tuple(1), z) + assert hyper((2, 1, 2), (1, 2, 1, 3), z) == hyper((2,), (1, 3), z) + u = hyper((2, 1, 2), (1, 2, 1, 3), z, evaluate=False) + assert u.ap == Tuple(1, 2, 2) + assert u.bq == Tuple(1, 1, 2, 3) + + h = hyper((1, 2), (3, 4, 5), z) + assert h.ap == Tuple(1, 2) + assert h.bq == Tuple(3, 4, 5) + assert h.argument == z + assert h.is_commutative is True + h = hyper((2, 1), (4, 3, 5), z) + assert h.ap == Tuple(1, 2) + assert h.bq == Tuple(3, 4, 5) + assert h.argument == z + assert h.is_commutative is True + + # just a few checks to make sure that all arguments go where they should + assert tn(hyper(Tuple(), Tuple(), z), exp(z), z) + assert tn(z*hyper((1, 1), Tuple(2), -z), log(1 + z), z) + + # differentiation + h = hyper( + (randcplx(), randcplx(), randcplx()), (randcplx(), randcplx()), z) + assert td(h, z) + + a1, a2, b1, b2, b3 = symbols('a1:3, b1:4') + assert hyper((a1, a2), (b1, b2, b3), z).diff(z) == \ + a1*a2/(b1*b2*b3) * hyper((a1 + 1, a2 + 1), (b1 + 1, b2 + 1, b3 + 1), z) + + # differentiation wrt parameters is not supported + assert hyper([z], [], z).diff(z) == Derivative(hyper([z], [], z), z) + + # hyper is unbranched wrt parameters + from sympy.functions.elementary.complexes import polar_lift + assert hyper([polar_lift(z)], [polar_lift(k)], polar_lift(x)) == \ + hyper([z], [k], polar_lift(x)) + + # hyper does not automatically evaluate anyway, but the test is to make + # sure that the evaluate keyword is accepted + assert hyper((1, 2), (1,), z, evaluate=False).func is hyper + + +def test_expand_func(): + # evaluation at 1 of Gauss' hypergeometric function: + from sympy.abc import a, b, c + from sympy.core.function import expand_func + a1, b1, c1 = randcplx(), randcplx(), randcplx() + 5 + assert expand_func(hyper([a, b], [c], 1)) == \ + gamma(c)*gamma(-a - b + c)/(gamma(-a + c)*gamma(-b + c)) + assert abs(expand_func(hyper([a1, b1], [c1], 1)).n() + - hyper([a1, b1], [c1], 1).n()) < 1e-10 + + # hyperexpand wrapper for hyper: + assert expand_func(hyper([], [], z)) == exp(z) + assert expand_func(hyper([1, 2, 3], [], z)) == hyper([1, 2, 3], [], z) + assert expand_func(meijerg([[1, 1], []], [[1], [0]], z)) == log(z + 1) + assert expand_func(meijerg([[1, 1], []], [[], []], z)) == \ + meijerg([[1, 1], []], [[], []], z) + + +def replace_dummy(expr, sym): + from sympy.core.symbol import Dummy + dum = expr.atoms(Dummy) + if not dum: + return expr + assert len(dum) == 1 + return expr.xreplace({dum.pop(): sym}) + + +def test_hyper_rewrite_sum(): + from sympy.concrete.summations import Sum + from sympy.core.symbol import Dummy + from sympy.functions.combinatorial.factorials import (RisingFactorial, factorial) + _k = Dummy("k") + assert replace_dummy(hyper((1, 2), (1, 3), x).rewrite(Sum), _k) == \ + Sum(x**_k / factorial(_k) * RisingFactorial(2, _k) / + RisingFactorial(3, _k), (_k, 0, oo)) + + assert hyper((1, 2, 3), (-1, 3), z).rewrite(Sum) == \ + hyper((1, 2, 3), (-1, 3), z) + + +def test_radius_of_convergence(): + assert hyper((1, 2), [3], z).radius_of_convergence == 1 + assert hyper((1, 2), [3, 4], z).radius_of_convergence is oo + assert hyper((1, 2, 3), [4], z).radius_of_convergence == 0 + assert hyper((0, 1, 2), [4], z).radius_of_convergence is oo + assert hyper((-1, 1, 2), [-4], z).radius_of_convergence == 0 + assert hyper((-1, -2, 2), [-1], z).radius_of_convergence is oo + assert hyper((-1, 2), [-1, -2], z).radius_of_convergence == 0 + assert hyper([-1, 1, 3], [-2, 2], z).radius_of_convergence == 1 + assert hyper([-1, 1], [-2, 2], z).radius_of_convergence is oo + assert hyper([-1, 1, 3], [-2], z).radius_of_convergence == 0 + assert hyper((-1, 2, 3, 4), [], z).radius_of_convergence is oo + + assert hyper([1, 1], [3], 1).convergence_statement == True + assert hyper([1, 1], [2], 1).convergence_statement == False + assert hyper([1, 1], [2], -1).convergence_statement == True + assert hyper([1, 1], [1], -1).convergence_statement == False + + +def test_meijer(): + raises(TypeError, lambda: meijerg(1, z)) + raises(TypeError, lambda: meijerg(((1,), (2,)), (3,), (4,), z)) + + assert meijerg(((1, 2), (3,)), ((4,), (5,)), z) == \ + meijerg(Tuple(1, 2), Tuple(3), Tuple(4), Tuple(5), z) + + g = meijerg((1, 2), (3, 4, 5), (6, 7, 8, 9), (10, 11, 12, 13, 14), z) + assert g.an == Tuple(1, 2) + assert g.ap == Tuple(1, 2, 3, 4, 5) + assert g.aother == Tuple(3, 4, 5) + assert g.bm == Tuple(6, 7, 8, 9) + assert g.bq == Tuple(6, 7, 8, 9, 10, 11, 12, 13, 14) + assert g.bother == Tuple(10, 11, 12, 13, 14) + assert g.argument == z + assert g.nu == 75 + assert g.delta == -1 + assert g.is_commutative is True + assert g.is_number is False + #issue 13071 + assert meijerg([[],[]], [[S.Half],[0]], 1).is_number is True + + assert meijerg([1, 2], [3], [4], [5], z).delta == S.Half + + # just a few checks to make sure that all arguments go where they should + assert tn(meijerg(Tuple(), Tuple(), Tuple(0), Tuple(), -z), exp(z), z) + assert tn(sqrt(pi)*meijerg(Tuple(), Tuple(), + Tuple(0), Tuple(S.Half), z**2/4), cos(z), z) + assert tn(meijerg(Tuple(1, 1), Tuple(), Tuple(1), Tuple(0), z), + log(1 + z), z) + + # test exceptions + raises(ValueError, lambda: meijerg(((3, 1), (2,)), ((oo,), (2, 0)), x)) + raises(ValueError, lambda: meijerg(((3, 1), (2,)), ((1,), (2, 0)), x)) + + # differentiation + g = meijerg((randcplx(),), (randcplx() + 2*I,), Tuple(), + (randcplx(), randcplx()), z) + assert td(g, z) + + g = meijerg(Tuple(), (randcplx(),), Tuple(), + (randcplx(), randcplx()), z) + assert td(g, z) + + g = meijerg(Tuple(), Tuple(), Tuple(randcplx()), + Tuple(randcplx(), randcplx()), z) + assert td(g, z) + + a1, a2, b1, b2, c1, c2, d1, d2 = symbols('a1:3, b1:3, c1:3, d1:3') + assert meijerg((a1, a2), (b1, b2), (c1, c2), (d1, d2), z).diff(z) == \ + (meijerg((a1 - 1, a2), (b1, b2), (c1, c2), (d1, d2), z) + + (a1 - 1)*meijerg((a1, a2), (b1, b2), (c1, c2), (d1, d2), z))/z + + assert meijerg([z, z], [], [], [], z).diff(z) == \ + Derivative(meijerg([z, z], [], [], [], z), z) + + # meijerg is unbranched wrt parameters + from sympy.functions.elementary.complexes import polar_lift as pl + assert meijerg([pl(a1)], [pl(a2)], [pl(b1)], [pl(b2)], pl(z)) == \ + meijerg([a1], [a2], [b1], [b2], pl(z)) + + # integrand + from sympy.abc import a, b, c, d, s + assert meijerg([a], [b], [c], [d], z).integrand(s) == \ + z**s*gamma(c - s)*gamma(-a + s + 1)/(gamma(b - s)*gamma(-d + s + 1)) + + +def test_meijerg_derivative(): + assert meijerg([], [1, 1], [0, 0, x], [], z).diff(x) == \ + log(z)*meijerg([], [1, 1], [0, 0, x], [], z) \ + + 2*meijerg([], [1, 1, 1], [0, 0, x, 0], [], z) + + y = randcplx() + a = 5 # mpmath chokes with non-real numbers, and Mod1 with floats + assert td(meijerg([x], [], [], [], y), x) + assert td(meijerg([x**2], [], [], [], y), x) + assert td(meijerg([], [x], [], [], y), x) + assert td(meijerg([], [], [x], [], y), x) + assert td(meijerg([], [], [], [x], y), x) + assert td(meijerg([x], [a], [a + 1], [], y), x) + assert td(meijerg([x], [a + 1], [a], [], y), x) + assert td(meijerg([x, a], [], [], [a + 1], y), x) + assert td(meijerg([x, a + 1], [], [], [a], y), x) + b = Rational(3, 2) + assert td(meijerg([a + 2], [b], [b - 3, x], [a], y), x) + + +def test_meijerg_period(): + assert meijerg([], [1], [0], [], x).get_period() == 2*pi + assert meijerg([1], [], [], [0], x).get_period() == 2*pi + assert meijerg([], [], [0], [], x).get_period() == 2*pi # exp(x) + assert meijerg( + [], [], [0], [S.Half], x).get_period() == 2*pi # cos(sqrt(x)) + assert meijerg( + [], [], [S.Half], [0], x).get_period() == 4*pi # sin(sqrt(x)) + assert meijerg([1, 1], [], [1], [0], x).get_period() is oo # log(1 + x) + + +def test_hyper_unpolarify(): + from sympy.functions.elementary.exponential import exp_polar + a = exp_polar(2*pi*I)*x + b = x + assert hyper([], [], a).argument == b + assert hyper([0], [], a).argument == a + assert hyper([0], [0], a).argument == b + assert hyper([0, 1], [0], a).argument == a + assert hyper([0, 1], [0], exp_polar(2*pi*I)).argument == 1 + + +@slow +def test_hyperrep(): + from sympy.functions.special.hyper import (HyperRep, HyperRep_atanh, + HyperRep_power1, HyperRep_power2, HyperRep_log1, HyperRep_asin1, + HyperRep_asin2, HyperRep_sqrts1, HyperRep_sqrts2, HyperRep_log2, + HyperRep_cosasin, HyperRep_sinasin) + # First test the base class works. + from sympy.functions.elementary.exponential import exp_polar + from sympy.functions.elementary.piecewise import Piecewise + a, b, c, d, z = symbols('a b c d z') + + class myrep(HyperRep): + @classmethod + def _expr_small(cls, x): + return a + + @classmethod + def _expr_small_minus(cls, x): + return b + + @classmethod + def _expr_big(cls, x, n): + return c*n + + @classmethod + def _expr_big_minus(cls, x, n): + return d*n + assert myrep(z).rewrite('nonrep') == Piecewise((0, abs(z) > 1), (a, True)) + assert myrep(exp_polar(I*pi)*z).rewrite('nonrep') == \ + Piecewise((0, abs(z) > 1), (b, True)) + assert myrep(exp_polar(2*I*pi)*z).rewrite('nonrep') == \ + Piecewise((c, abs(z) > 1), (a, True)) + assert myrep(exp_polar(3*I*pi)*z).rewrite('nonrep') == \ + Piecewise((d, abs(z) > 1), (b, True)) + assert myrep(exp_polar(4*I*pi)*z).rewrite('nonrep') == \ + Piecewise((2*c, abs(z) > 1), (a, True)) + assert myrep(exp_polar(5*I*pi)*z).rewrite('nonrep') == \ + Piecewise((2*d, abs(z) > 1), (b, True)) + assert myrep(z).rewrite('nonrepsmall') == a + assert myrep(exp_polar(I*pi)*z).rewrite('nonrepsmall') == b + + def t(func, hyp, z): + """ Test that func is a valid representation of hyp. """ + # First test that func agrees with hyp for small z + if not tn(func.rewrite('nonrepsmall'), hyp, z, + a=Rational(-1, 2), b=Rational(-1, 2), c=S.Half, d=S.Half): + return False + # Next check that the two small representations agree. + if not tn( + func.rewrite('nonrepsmall').subs( + z, exp_polar(I*pi)*z).replace(exp_polar, exp), + func.subs(z, exp_polar(I*pi)*z).rewrite('nonrepsmall'), + z, a=Rational(-1, 2), b=Rational(-1, 2), c=S.Half, d=S.Half): + return False + # Next check continuity along exp_polar(I*pi)*t + expr = func.subs(z, exp_polar(I*pi)*z).rewrite('nonrep') + if abs(expr.subs(z, 1 + 1e-15).n() - expr.subs(z, 1 - 1e-15).n()) > 1e-10: + return False + # Finally check continuity of the big reps. + + def dosubs(func, a, b): + rv = func.subs(z, exp_polar(a)*z).rewrite('nonrep') + return rv.subs(z, exp_polar(b)*z).replace(exp_polar, exp) + for n in [0, 1, 2, 3, 4, -1, -2, -3, -4]: + expr1 = dosubs(func, 2*I*pi*n, I*pi/2) + expr2 = dosubs(func, 2*I*pi*n + I*pi, -I*pi/2) + if not tn(expr1, expr2, z): + return False + expr1 = dosubs(func, 2*I*pi*(n + 1), -I*pi/2) + expr2 = dosubs(func, 2*I*pi*n + I*pi, I*pi/2) + if not tn(expr1, expr2, z): + return False + return True + + # Now test the various representatives. + a = Rational(1, 3) + assert t(HyperRep_atanh(z), hyper([S.Half, 1], [Rational(3, 2)], z), z) + assert t(HyperRep_power1(a, z), hyper([-a], [], z), z) + assert t(HyperRep_power2(a, z), hyper([a, a - S.Half], [2*a], z), z) + assert t(HyperRep_log1(z), -z*hyper([1, 1], [2], z), z) + assert t(HyperRep_asin1(z), hyper([S.Half, S.Half], [Rational(3, 2)], z), z) + assert t(HyperRep_asin2(z), hyper([1, 1], [Rational(3, 2)], z), z) + assert t(HyperRep_sqrts1(a, z), hyper([-a, S.Half - a], [S.Half], z), z) + assert t(HyperRep_sqrts2(a, z), + -2*z/(2*a + 1)*hyper([-a - S.Half, -a], [S.Half], z).diff(z), z) + assert t(HyperRep_log2(z), -z/4*hyper([Rational(3, 2), 1, 1], [2, 2], z), z) + assert t(HyperRep_cosasin(a, z), hyper([-a, a], [S.Half], z), z) + assert t(HyperRep_sinasin(a, z), 2*a*z*hyper([1 - a, 1 + a], [Rational(3, 2)], z), z) + + +@slow +def test_meijerg_eval(): + from sympy.functions.elementary.exponential import exp_polar + from sympy.functions.special.bessel import besseli + from sympy.abc import l + a = randcplx() + arg = x*exp_polar(k*pi*I) + expr1 = pi*meijerg([[], [(a + 1)/2]], [[a/2], [-a/2, (a + 1)/2]], arg**2/4) + expr2 = besseli(a, arg) + + # Test that the two expressions agree for all arguments. + for x_ in [0.5, 1.5]: + for k_ in [0.0, 0.1, 0.3, 0.5, 0.8, 1, 5.751, 15.3]: + assert abs((expr1 - expr2).n(subs={x: x_, k: k_})) < 1e-10 + assert abs((expr1 - expr2).n(subs={x: x_, k: -k_})) < 1e-10 + + # Test continuity independently + eps = 1e-13 + expr2 = expr1.subs(k, l) + for x_ in [0.5, 1.5]: + for k_ in [0.5, Rational(1, 3), 0.25, 0.75, Rational(2, 3), 1.0, 1.5]: + assert abs((expr1 - expr2).n( + subs={x: x_, k: k_ + eps, l: k_ - eps})) < 1e-10 + assert abs((expr1 - expr2).n( + subs={x: x_, k: -k_ + eps, l: -k_ - eps})) < 1e-10 + + expr = (meijerg(((0.5,), ()), ((0.5, 0, 0.5), ()), exp_polar(-I*pi)/4) + + meijerg(((0.5,), ()), ((0.5, 0, 0.5), ()), exp_polar(I*pi)/4)) \ + /(2*sqrt(pi)) + assert (expr - pi/exp(1)).n(chop=True) == 0 + + +def test_limits(): + k, x = symbols('k, x') + assert hyper((1,), (Rational(4, 3), Rational(5, 3)), k**2).series(k) == \ + 1 + 9*k**2/20 + 81*k**4/1120 + O(k**6) # issue 6350 + + # https://github.com/sympy/sympy/issues/11465 + assert limit(1/hyper((1, ), (1, ), x), x, 0) == 1 + + +def test_appellf1(): + a, b1, b2, c, x, y = symbols('a b1 b2 c x y') + assert appellf1(a, b2, b1, c, y, x) == appellf1(a, b1, b2, c, x, y) + assert appellf1(a, b1, b1, c, y, x) == appellf1(a, b1, b1, c, x, y) + assert appellf1(a, b1, b2, c, S.Zero, S.Zero) is S.One + + f = appellf1(a, b1, b2, c, S.Zero, S.Zero, evaluate=False) + assert f.func is appellf1 + assert f.doit() is S.One + + +def test_derivative_appellf1(): + from sympy.core.function import diff + a, b1, b2, c, x, y, z = symbols('a b1 b2 c x y z') + assert diff(appellf1(a, b1, b2, c, x, y), x) == a*b1*appellf1(a + 1, b2, b1 + 1, c + 1, y, x)/c + assert diff(appellf1(a, b1, b2, c, x, y), y) == a*b2*appellf1(a + 1, b1, b2 + 1, c + 1, x, y)/c + assert diff(appellf1(a, b1, b2, c, x, y), z) == 0 + assert diff(appellf1(a, b1, b2, c, x, y), a) == Derivative(appellf1(a, b1, b2, c, x, y), a) + + +def test_eval_nseries(): + a1, b1, a2, b2 = symbols('a1 b1 a2 b2') + assert hyper((1,2), (1,2,3), x**2)._eval_nseries(x, 7, None) == \ + 1 + x**2/3 + x**4/24 + x**6/360 + O(x**7) + assert exp(x)._eval_nseries(x,7,None) == \ + hyper((a1, b1), (a1, b1), x)._eval_nseries(x, 7, None) + assert hyper((a1, a2), (b1, b2), x)._eval_nseries(z, 7, None) ==\ + hyper((a1, a2), (b1, b2), x) + O(z**7) + assert hyper((-S(1)/2, S(1)/2), (1,), 4*x/(x + 1)).nseries(x) == \ + 1 - x + x**2/4 - 3*x**3/4 - 15*x**4/64 - 93*x**5/64 + O(x**6) + assert (pi/2*hyper((-S(1)/2, S(1)/2), (1,), 4*x/(x + 1))).nseries(x) == \ + pi/2 - pi*x/2 + pi*x**2/8 - 3*pi*x**3/8 - 15*pi*x**4/128 - 93*pi*x**5/128 + O(x**6) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_mathieu.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_mathieu.py new file mode 100644 index 0000000000000000000000000000000000000000..b9296f0657d920c8d297f820fb3ab8b6a53129ab --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_mathieu.py @@ -0,0 +1,29 @@ +from sympy.core.function import diff +from sympy.functions.elementary.complexes import conjugate +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (cos, sin) +from sympy.functions.special.mathieu_functions import (mathieuc, mathieucprime, mathieus, mathieusprime) + +from sympy.abc import a, q, z + + +def test_mathieus(): + assert isinstance(mathieus(a, q, z), mathieus) + assert mathieus(a, 0, z) == sin(sqrt(a)*z) + assert conjugate(mathieus(a, q, z)) == mathieus(conjugate(a), conjugate(q), conjugate(z)) + assert diff(mathieus(a, q, z), z) == mathieusprime(a, q, z) + +def test_mathieuc(): + assert isinstance(mathieuc(a, q, z), mathieuc) + assert mathieuc(a, 0, z) == cos(sqrt(a)*z) + assert diff(mathieuc(a, q, z), z) == mathieucprime(a, q, z) + +def test_mathieusprime(): + assert isinstance(mathieusprime(a, q, z), mathieusprime) + assert mathieusprime(a, 0, z) == sqrt(a)*cos(sqrt(a)*z) + assert diff(mathieusprime(a, q, z), z) == (-a + 2*q*cos(2*z))*mathieus(a, q, z) + +def test_mathieucprime(): + assert isinstance(mathieucprime(a, q, z), mathieucprime) + assert mathieucprime(a, 0, z) == -sqrt(a)*sin(sqrt(a)*z) + assert diff(mathieucprime(a, q, z), z) == (-a + 2*q*cos(2*z))*mathieuc(a, q, z) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_singularity_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_singularity_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..dbd85cb0c7e5524d4fe1441615879b9776ad1693 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_singularity_functions.py @@ -0,0 +1,129 @@ +from sympy.core.function import (Derivative, diff) +from sympy.core.numbers import (Float, I, nan, oo, pi) +from sympy.core.relational import Eq +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.special.delta_functions import (DiracDelta, Heaviside) +from sympy.functions.special.singularity_functions import SingularityFunction +from sympy.series.order import O + + +from sympy.core.expr import unchanged +from sympy.core.function import ArgumentIndexError +from sympy.testing.pytest import raises + +x, y, a, n = symbols('x y a n') + + +def test_fdiff(): + assert SingularityFunction(x, 4, 5).fdiff() == 5*SingularityFunction(x, 4, 4) + assert SingularityFunction(x, 4, -1).fdiff() == SingularityFunction(x, 4, -2) + assert SingularityFunction(x, 4, -2).fdiff() == SingularityFunction(x, 4, -3) + assert SingularityFunction(x, 4, -3).fdiff() == SingularityFunction(x, 4, -4) + assert SingularityFunction(x, 4, 0).fdiff() == SingularityFunction(x, 4, -1) + + assert SingularityFunction(y, 6, 2).diff(y) == 2*SingularityFunction(y, 6, 1) + assert SingularityFunction(y, -4, -1).diff(y) == SingularityFunction(y, -4, -2) + assert SingularityFunction(y, 4, 0).diff(y) == SingularityFunction(y, 4, -1) + assert SingularityFunction(y, 4, 0).diff(y, 2) == SingularityFunction(y, 4, -2) + + n = Symbol('n', positive=True) + assert SingularityFunction(x, a, n).fdiff() == n*SingularityFunction(x, a, n - 1) + assert SingularityFunction(y, a, n).diff(y) == n*SingularityFunction(y, a, n - 1) + + expr_in = 4*SingularityFunction(x, a, n) + 3*SingularityFunction(x, a, -1) + -10*SingularityFunction(x, a, 0) + expr_out = n*4*SingularityFunction(x, a, n - 1) + 3*SingularityFunction(x, a, -2) - 10*SingularityFunction(x, a, -1) + assert diff(expr_in, x) == expr_out + + assert SingularityFunction(x, -10, 5).diff(evaluate=False) == ( + Derivative(SingularityFunction(x, -10, 5), x)) + + raises(ArgumentIndexError, lambda: SingularityFunction(x, 4, 5).fdiff(2)) + + +def test_eval(): + assert SingularityFunction(x, a, n).func == SingularityFunction + assert unchanged(SingularityFunction, x, 5, n) + assert SingularityFunction(5, 3, 2) == 4 + assert SingularityFunction(3, 5, 1) == 0 + assert SingularityFunction(3, 3, 0) == 1 + assert SingularityFunction(3, 3, 1) == 0 + assert SingularityFunction(Symbol('z', zero=True), 0, 1) == 0 # like sin(z) == 0 + assert SingularityFunction(4, 4, -1) is oo + assert SingularityFunction(4, 2, -1) == 0 + assert SingularityFunction(4, 7, -1) == 0 + assert SingularityFunction(5, 6, -2) == 0 + assert SingularityFunction(4, 2, -2) == 0 + assert SingularityFunction(4, 4, -2) is oo + assert SingularityFunction(4, 2, -3) == 0 + assert SingularityFunction(8, 8, -3) is oo + assert SingularityFunction(4, 2, -4) == 0 + assert SingularityFunction(8, 8, -4) is oo + assert (SingularityFunction(6.1, 4, 5)).evalf(5) == Float('40.841', '5') + assert SingularityFunction(6.1, pi, 2) == (-pi + 6.1)**2 + assert SingularityFunction(x, a, nan) is nan + assert SingularityFunction(x, nan, 1) is nan + assert SingularityFunction(nan, a, n) is nan + + raises(ValueError, lambda: SingularityFunction(x, a, I)) + raises(ValueError, lambda: SingularityFunction(2*I, I, n)) + raises(ValueError, lambda: SingularityFunction(x, a, -5)) + + +def test_leading_term(): + l = Symbol('l', positive=True) + assert SingularityFunction(x, 3, 2).as_leading_term(x) == 0 + assert SingularityFunction(x, -2, 1).as_leading_term(x) == 2 + assert SingularityFunction(x, 0, 0).as_leading_term(x) == 1 + assert SingularityFunction(x, 0, 0).as_leading_term(x, cdir=-1) == 0 + assert SingularityFunction(x, 0, -1).as_leading_term(x) == 0 + assert SingularityFunction(x, 0, -2).as_leading_term(x) == 0 + assert SingularityFunction(x, 0, -3).as_leading_term(x) == 0 + assert SingularityFunction(x, 0, -4).as_leading_term(x) == 0 + assert (SingularityFunction(x + l, 0, 1)/2\ + - SingularityFunction(x + l, l/2, 1)\ + + SingularityFunction(x + l, l, 1)/2).as_leading_term(x) == -x/2 + + +def test_series(): + l = Symbol('l', positive=True) + assert SingularityFunction(x, -3, 2).series(x) == x**2 + 6*x + 9 + assert SingularityFunction(x, -2, 1).series(x) == x + 2 + assert SingularityFunction(x, 0, 0).series(x) == 1 + assert SingularityFunction(x, 0, 0).series(x, dir='-') == 0 + assert SingularityFunction(x, 0, -1).series(x) == 0 + assert SingularityFunction(x, 0, -2).series(x) == 0 + assert SingularityFunction(x, 0, -3).series(x) == 0 + assert SingularityFunction(x, 0, -4).series(x) == 0 + assert (SingularityFunction(x + l, 0, 1)/2\ + - SingularityFunction(x + l, l/2, 1)\ + + SingularityFunction(x + l, l, 1)/2).nseries(x) == -x/2 + O(x**6) + + +def test_rewrite(): + assert SingularityFunction(x, 4, 5).rewrite(Piecewise) == ( + Piecewise(((x - 4)**5, x - 4 >= 0), (0, True))) + assert SingularityFunction(x, -10, 0).rewrite(Piecewise) == ( + Piecewise((1, x + 10 >= 0), (0, True))) + assert SingularityFunction(x, 2, -1).rewrite(Piecewise) == ( + Piecewise((oo, Eq(x - 2, 0)), (0, True))) + assert SingularityFunction(x, 0, -2).rewrite(Piecewise) == ( + Piecewise((oo, Eq(x, 0)), (0, True))) + + n = Symbol('n', nonnegative=True) + p = SingularityFunction(x, a, n).rewrite(Piecewise) + assert p == ( + Piecewise(((x - a)**n, x - a >= 0), (0, True))) + assert p.subs(x, a).subs(n, 0) == 1 + + expr_in = SingularityFunction(x, 4, 5) + SingularityFunction(x, -3, -1) - SingularityFunction(x, 0, -2) + expr_out = (x - 4)**5*Heaviside(x - 4, 1) + DiracDelta(x + 3) - DiracDelta(x, 1) + assert expr_in.rewrite(Heaviside) == expr_out + assert expr_in.rewrite(DiracDelta) == expr_out + assert expr_in.rewrite('HeavisideDiracDelta') == expr_out + + expr_in = SingularityFunction(x, a, n) + SingularityFunction(x, a, -1) - SingularityFunction(x, a, -2) + expr_out = (x - a)**n*Heaviside(x - a, 1) + DiracDelta(x - a) + DiracDelta(a - x, 1) + assert expr_in.rewrite(Heaviside) == expr_out + assert expr_in.rewrite(DiracDelta) == expr_out + assert expr_in.rewrite('HeavisideDiracDelta') == expr_out diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_spec_polynomials.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_spec_polynomials.py new file mode 100644 index 0000000000000000000000000000000000000000..584ad3cf97df8b9d92da9fc7805ab4296f40671c --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_spec_polynomials.py @@ -0,0 +1,475 @@ +from sympy.concrete.summations import Sum +from sympy.core.function import (Derivative, diff) +from sympy.core.numbers import (Rational, oo, pi, zoo) +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, Symbol) +from sympy.functions.combinatorial.factorials import (RisingFactorial, binomial, factorial) +from sympy.functions.elementary.complexes import conjugate +from sympy.functions.elementary.exponential import exp +from sympy.functions.elementary.integers import floor +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import cos +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import hyper +from sympy.functions.special.polynomials import (assoc_laguerre, assoc_legendre, chebyshevt, chebyshevt_root, chebyshevu, chebyshevu_root, gegenbauer, hermite, hermite_prob, jacobi, jacobi_normalized, laguerre, legendre) +from sympy.polys.orthopolys import laguerre_poly +from sympy.polys.polyroots import roots + +from sympy.core.expr import unchanged +from sympy.core.function import ArgumentIndexError +from sympy.testing.pytest import raises + + +x = Symbol('x') + + +def test_jacobi(): + n = Symbol("n") + a = Symbol("a") + b = Symbol("b") + + assert jacobi(0, a, b, x) == 1 + assert jacobi(1, a, b, x) == a/2 - b/2 + x*(a/2 + b/2 + 1) + + assert jacobi(n, a, a, x) == RisingFactorial( + a + 1, n)*gegenbauer(n, a + S.Half, x)/RisingFactorial(2*a + 1, n) + assert jacobi(n, a, -a, x) == ((-1)**a*(-x + 1)**(-a/2)*(x + 1)**(a/2)*assoc_legendre(n, a, x)* + factorial(-a + n)*gamma(a + n + 1)/(factorial(a + n)*gamma(n + 1))) + assert jacobi(n, -b, b, x) == ((-x + 1)**(b/2)*(x + 1)**(-b/2)*assoc_legendre(n, b, x)* + gamma(-b + n + 1)/gamma(n + 1)) + assert jacobi(n, 0, 0, x) == legendre(n, x) + assert jacobi(n, S.Half, S.Half, x) == RisingFactorial( + Rational(3, 2), n)*chebyshevu(n, x)/factorial(n + 1) + assert jacobi(n, Rational(-1, 2), Rational(-1, 2), x) == RisingFactorial( + S.Half, n)*chebyshevt(n, x)/factorial(n) + + X = jacobi(n, a, b, x) + assert isinstance(X, jacobi) + + assert jacobi(n, a, b, -x) == (-1)**n*jacobi(n, b, a, x) + assert jacobi(n, a, b, 0) == 2**(-n)*gamma(a + n + 1)*hyper( + (-b - n, -n), (a + 1,), -1)/(factorial(n)*gamma(a + 1)) + assert jacobi(n, a, b, 1) == RisingFactorial(a + 1, n)/factorial(n) + + m = Symbol("m", positive=True) + assert jacobi(m, a, b, oo) == oo*RisingFactorial(a + b + m + 1, m) + assert unchanged(jacobi, n, a, b, oo) + + assert conjugate(jacobi(m, a, b, x)) == \ + jacobi(m, conjugate(a), conjugate(b), conjugate(x)) + + _k = Dummy('k') + assert diff(jacobi(n, a, b, x), n) == Derivative(jacobi(n, a, b, x), n) + assert diff(jacobi(n, a, b, x), a).dummy_eq(Sum((jacobi(n, a, b, x) + + (2*_k + a + b + 1)*RisingFactorial(_k + b + 1, -_k + n)*jacobi(_k, a, + b, x)/((-_k + n)*RisingFactorial(_k + a + b + 1, -_k + n)))/(_k + a + + b + n + 1), (_k, 0, n - 1))) + assert diff(jacobi(n, a, b, x), b).dummy_eq(Sum(((-1)**(-_k + n)*(2*_k + + a + b + 1)*RisingFactorial(_k + a + 1, -_k + n)*jacobi(_k, a, b, x)/ + ((-_k + n)*RisingFactorial(_k + a + b + 1, -_k + n)) + jacobi(n, a, + b, x))/(_k + a + b + n + 1), (_k, 0, n - 1))) + assert diff(jacobi(n, a, b, x), x) == \ + (a/2 + b/2 + n/2 + S.Half)*jacobi(n - 1, a + 1, b + 1, x) + + assert jacobi_normalized(n, a, b, x) == \ + (jacobi(n, a, b, x)/sqrt(2**(a + b + 1)*gamma(a + n + 1)*gamma(b + n + 1) + /((a + b + 2*n + 1)*factorial(n)*gamma(a + b + n + 1)))) + + raises(ValueError, lambda: jacobi(-2.1, a, b, x)) + raises(ValueError, lambda: jacobi(Dummy(positive=True, integer=True), 1, 2, oo)) + + assert jacobi(n, a, b, x).rewrite(Sum).dummy_eq(Sum((S.Half - x/2) + **_k*RisingFactorial(-n, _k)*RisingFactorial(_k + a + 1, -_k + n)* + RisingFactorial(a + b + n + 1, _k)/factorial(_k), (_k, 0, n))/factorial(n)) + assert jacobi(n, a, b, x).rewrite("polynomial").dummy_eq(Sum((S.Half - x/2) + **_k*RisingFactorial(-n, _k)*RisingFactorial(_k + a + 1, -_k + n)* + RisingFactorial(a + b + n + 1, _k)/factorial(_k), (_k, 0, n))/factorial(n)) + raises(ArgumentIndexError, lambda: jacobi(n, a, b, x).fdiff(5)) + + +def test_gegenbauer(): + n = Symbol("n") + a = Symbol("a") + + assert gegenbauer(0, a, x) == 1 + assert gegenbauer(1, a, x) == 2*a*x + assert gegenbauer(2, a, x) == -a + x**2*(2*a**2 + 2*a) + assert gegenbauer(3, a, x) == \ + x**3*(4*a**3/3 + 4*a**2 + a*Rational(8, 3)) + x*(-2*a**2 - 2*a) + + assert gegenbauer(-1, a, x) == 0 + assert gegenbauer(n, S.Half, x) == legendre(n, x) + assert gegenbauer(n, 1, x) == chebyshevu(n, x) + assert gegenbauer(n, -1, x) == 0 + + X = gegenbauer(n, a, x) + assert isinstance(X, gegenbauer) + + assert gegenbauer(n, a, -x) == (-1)**n*gegenbauer(n, a, x) + assert gegenbauer(n, a, 0) == 2**n*sqrt(pi) * \ + gamma(a + n/2)/(gamma(a)*gamma(-n/2 + S.Half)*gamma(n + 1)) + assert gegenbauer(n, a, 1) == gamma(2*a + n)/(gamma(2*a)*gamma(n + 1)) + + assert gegenbauer(n, Rational(3, 4), -1) is zoo + assert gegenbauer(n, Rational(1, 4), -1) == (sqrt(2)*cos(pi*(n + S.One/4))* + gamma(n + S.Half)/(sqrt(pi)*gamma(n + 1))) + + m = Symbol("m", positive=True) + assert gegenbauer(m, a, oo) == oo*RisingFactorial(a, m) + assert unchanged(gegenbauer, n, a, oo) + + assert conjugate(gegenbauer(n, a, x)) == gegenbauer(n, conjugate(a), conjugate(x)) + + _k = Dummy('k') + + assert diff(gegenbauer(n, a, x), n) == Derivative(gegenbauer(n, a, x), n) + assert diff(gegenbauer(n, a, x), a).dummy_eq(Sum((2*(-1)**(-_k + n) + 2)* + (_k + a)*gegenbauer(_k, a, x)/((-_k + n)*(_k + 2*a + n)) + ((2*_k + + 2)/((_k + 2*a)*(2*_k + 2*a + 1)) + 2/(_k + 2*a + n))*gegenbauer(n, a + , x), (_k, 0, n - 1))) + assert diff(gegenbauer(n, a, x), x) == 2*a*gegenbauer(n - 1, a + 1, x) + + assert gegenbauer(n, a, x).rewrite(Sum).dummy_eq( + Sum((-1)**_k*(2*x)**(-2*_k + n)*RisingFactorial(a, -_k + n) + /(factorial(_k)*factorial(-2*_k + n)), (_k, 0, floor(n/2)))) + assert gegenbauer(n, a, x).rewrite("polynomial").dummy_eq( + Sum((-1)**_k*(2*x)**(-2*_k + n)*RisingFactorial(a, -_k + n) + /(factorial(_k)*factorial(-2*_k + n)), (_k, 0, floor(n/2)))) + + raises(ArgumentIndexError, lambda: gegenbauer(n, a, x).fdiff(4)) + + +def test_legendre(): + assert legendre(0, x) == 1 + assert legendre(1, x) == x + assert legendre(2, x) == ((3*x**2 - 1)/2).expand() + assert legendre(3, x) == ((5*x**3 - 3*x)/2).expand() + assert legendre(4, x) == ((35*x**4 - 30*x**2 + 3)/8).expand() + assert legendre(5, x) == ((63*x**5 - 70*x**3 + 15*x)/8).expand() + assert legendre(6, x) == ((231*x**6 - 315*x**4 + 105*x**2 - 5)/16).expand() + + assert legendre(10, -1) == 1 + assert legendre(11, -1) == -1 + assert legendre(10, 1) == 1 + assert legendre(11, 1) == 1 + assert legendre(10, 0) != 0 + assert legendre(11, 0) == 0 + + assert legendre(-1, x) == 1 + k = Symbol('k') + assert legendre(5 - k, x).subs(k, 2) == ((5*x**3 - 3*x)/2).expand() + + assert roots(legendre(4, x), x) == { + sqrt(Rational(3, 7) - Rational(2, 35)*sqrt(30)): 1, + -sqrt(Rational(3, 7) - Rational(2, 35)*sqrt(30)): 1, + sqrt(Rational(3, 7) + Rational(2, 35)*sqrt(30)): 1, + -sqrt(Rational(3, 7) + Rational(2, 35)*sqrt(30)): 1, + } + + n = Symbol("n") + + X = legendre(n, x) + assert isinstance(X, legendre) + assert unchanged(legendre, n, x) + + assert legendre(n, 0) == sqrt(pi)/(gamma(S.Half - n/2)*gamma(n/2 + 1)) + assert legendre(n, 1) == 1 + assert legendre(n, oo) is oo + assert legendre(-n, x) == legendre(n - 1, x) + assert legendre(n, -x) == (-1)**n*legendre(n, x) + assert unchanged(legendre, -n + k, x) + + assert conjugate(legendre(n, x)) == legendre(n, conjugate(x)) + + assert diff(legendre(n, x), x) == \ + n*(x*legendre(n, x) - legendre(n - 1, x))/(x**2 - 1) + assert diff(legendre(n, x), n) == Derivative(legendre(n, x), n) + + _k = Dummy('k') + assert legendre(n, x).rewrite(Sum).dummy_eq(Sum((-1)**_k*(S.Half - + x/2)**_k*(x/2 + S.Half)**(-_k + n)*binomial(n, _k)**2, (_k, 0, n))) + assert legendre(n, x).rewrite("polynomial").dummy_eq(Sum((-1)**_k*(S.Half - + x/2)**_k*(x/2 + S.Half)**(-_k + n)*binomial(n, _k)**2, (_k, 0, n))) + raises(ArgumentIndexError, lambda: legendre(n, x).fdiff(1)) + raises(ArgumentIndexError, lambda: legendre(n, x).fdiff(3)) + + +def test_assoc_legendre(): + Plm = assoc_legendre + Q = sqrt(1 - x**2) + + assert Plm(0, 0, x) == 1 + assert Plm(1, 0, x) == x + assert Plm(1, 1, x) == -Q + assert Plm(2, 0, x) == (3*x**2 - 1)/2 + assert Plm(2, 1, x) == -3*x*Q + assert Plm(2, 2, x) == 3*Q**2 + assert Plm(3, 0, x) == (5*x**3 - 3*x)/2 + assert Plm(3, 1, x).expand() == (( 3*(1 - 5*x**2)/2 ).expand() * Q).expand() + assert Plm(3, 2, x) == 15*x * Q**2 + assert Plm(3, 3, x) == -15 * Q**3 + + # negative m + assert Plm(1, -1, x) == -Plm(1, 1, x)/2 + assert Plm(2, -2, x) == Plm(2, 2, x)/24 + assert Plm(2, -1, x) == -Plm(2, 1, x)/6 + assert Plm(3, -3, x) == -Plm(3, 3, x)/720 + assert Plm(3, -2, x) == Plm(3, 2, x)/120 + assert Plm(3, -1, x) == -Plm(3, 1, x)/12 + + n = Symbol("n") + m = Symbol("m") + X = Plm(n, m, x) + assert isinstance(X, assoc_legendre) + + assert Plm(n, 0, x) == legendre(n, x) + assert Plm(n, m, 0) == 2**m*sqrt(pi)/(gamma(-m/2 - n/2 + + S.Half)*gamma(-m/2 + n/2 + 1)) + + assert diff(Plm(m, n, x), x) == (m*x*assoc_legendre(m, n, x) - + (m + n)*assoc_legendre(m - 1, n, x))/(x**2 - 1) + + _k = Dummy('k') + assert Plm(m, n, x).rewrite(Sum).dummy_eq( + (1 - x**2)**(n/2)*Sum((-1)**_k*2**(-m)*x**(-2*_k + m - n)*factorial + (-2*_k + 2*m)/(factorial(_k)*factorial(-_k + m)*factorial(-2*_k + m + - n)), (_k, 0, floor(m/2 - n/2)))) + assert Plm(m, n, x).rewrite("polynomial").dummy_eq( + (1 - x**2)**(n/2)*Sum((-1)**_k*2**(-m)*x**(-2*_k + m - n)*factorial + (-2*_k + 2*m)/(factorial(_k)*factorial(-_k + m)*factorial(-2*_k + m + - n)), (_k, 0, floor(m/2 - n/2)))) + assert conjugate(assoc_legendre(n, m, x)) == \ + assoc_legendre(n, conjugate(m), conjugate(x)) + raises(ValueError, lambda: Plm(0, 1, x)) + raises(ValueError, lambda: Plm(-1, 1, x)) + raises(ArgumentIndexError, lambda: Plm(n, m, x).fdiff(1)) + raises(ArgumentIndexError, lambda: Plm(n, m, x).fdiff(2)) + raises(ArgumentIndexError, lambda: Plm(n, m, x).fdiff(4)) + + +def test_chebyshev(): + assert chebyshevt(0, x) == 1 + assert chebyshevt(1, x) == x + assert chebyshevt(2, x) == 2*x**2 - 1 + assert chebyshevt(3, x) == 4*x**3 - 3*x + + for n in range(1, 4): + for k in range(n): + z = chebyshevt_root(n, k) + assert chebyshevt(n, z) == 0 + raises(ValueError, lambda: chebyshevt_root(n, n)) + + for n in range(1, 4): + for k in range(n): + z = chebyshevu_root(n, k) + assert chebyshevu(n, z) == 0 + raises(ValueError, lambda: chebyshevu_root(n, n)) + + n = Symbol("n") + X = chebyshevt(n, x) + assert isinstance(X, chebyshevt) + assert unchanged(chebyshevt, n, x) + assert chebyshevt(n, -x) == (-1)**n*chebyshevt(n, x) + assert chebyshevt(-n, x) == chebyshevt(n, x) + + assert chebyshevt(n, 0) == cos(pi*n/2) + assert chebyshevt(n, 1) == 1 + assert chebyshevt(n, oo) is oo + + assert conjugate(chebyshevt(n, x)) == chebyshevt(n, conjugate(x)) + + assert diff(chebyshevt(n, x), x) == n*chebyshevu(n - 1, x) + + X = chebyshevu(n, x) + assert isinstance(X, chebyshevu) + + y = Symbol('y') + assert chebyshevu(n, -x) == (-1)**n*chebyshevu(n, x) + assert chebyshevu(-n, x) == -chebyshevu(n - 2, x) + assert unchanged(chebyshevu, -n + y, x) + + assert chebyshevu(n, 0) == cos(pi*n/2) + assert chebyshevu(n, 1) == n + 1 + assert chebyshevu(n, oo) is oo + + assert conjugate(chebyshevu(n, x)) == chebyshevu(n, conjugate(x)) + + assert diff(chebyshevu(n, x), x) == \ + (-x*chebyshevu(n, x) + (n + 1)*chebyshevt(n + 1, x))/(x**2 - 1) + + _k = Dummy('k') + assert chebyshevt(n, x).rewrite(Sum).dummy_eq(Sum(x**(-2*_k + n) + *(x**2 - 1)**_k*binomial(n, 2*_k), (_k, 0, floor(n/2)))) + assert chebyshevt(n, x).rewrite("polynomial").dummy_eq(Sum(x**(-2*_k + n) + *(x**2 - 1)**_k*binomial(n, 2*_k), (_k, 0, floor(n/2)))) + assert chebyshevu(n, x).rewrite(Sum).dummy_eq(Sum((-1)**_k*(2*x) + **(-2*_k + n)*factorial(-_k + n)/(factorial(_k)* + factorial(-2*_k + n)), (_k, 0, floor(n/2)))) + assert chebyshevu(n, x).rewrite("polynomial").dummy_eq(Sum((-1)**_k*(2*x) + **(-2*_k + n)*factorial(-_k + n)/(factorial(_k)* + factorial(-2*_k + n)), (_k, 0, floor(n/2)))) + raises(ArgumentIndexError, lambda: chebyshevt(n, x).fdiff(1)) + raises(ArgumentIndexError, lambda: chebyshevt(n, x).fdiff(3)) + raises(ArgumentIndexError, lambda: chebyshevu(n, x).fdiff(1)) + raises(ArgumentIndexError, lambda: chebyshevu(n, x).fdiff(3)) + + +def test_hermite(): + assert hermite(0, x) == 1 + assert hermite(1, x) == 2*x + assert hermite(2, x) == 4*x**2 - 2 + assert hermite(3, x) == 8*x**3 - 12*x + assert hermite(4, x) == 16*x**4 - 48*x**2 + 12 + assert hermite(6, x) == 64*x**6 - 480*x**4 + 720*x**2 - 120 + + n = Symbol("n") + assert unchanged(hermite, n, x) + assert hermite(n, -x) == (-1)**n*hermite(n, x) + assert unchanged(hermite, -n, x) + + assert hermite(n, 0) == 2**n*sqrt(pi)/gamma(S.Half - n/2) + assert hermite(n, oo) is oo + + assert conjugate(hermite(n, x)) == hermite(n, conjugate(x)) + + _k = Dummy('k') + assert hermite(n, x).rewrite(Sum).dummy_eq(factorial(n)*Sum((-1) + **_k*(2*x)**(-2*_k + n)/(factorial(_k)*factorial(-2*_k + n)), (_k, + 0, floor(n/2)))) + assert hermite(n, x).rewrite("polynomial").dummy_eq(factorial(n)*Sum((-1) + **_k*(2*x)**(-2*_k + n)/(factorial(_k)*factorial(-2*_k + n)), (_k, + 0, floor(n/2)))) + + assert diff(hermite(n, x), x) == 2*n*hermite(n - 1, x) + assert diff(hermite(n, x), n) == Derivative(hermite(n, x), n) + raises(ArgumentIndexError, lambda: hermite(n, x).fdiff(3)) + + assert hermite(n, x).rewrite(hermite_prob) == \ + sqrt(2)**n * hermite_prob(n, x*sqrt(2)) + + +def test_hermite_prob(): + assert hermite_prob(0, x) == 1 + assert hermite_prob(1, x) == x + assert hermite_prob(2, x) == x**2 - 1 + assert hermite_prob(3, x) == x**3 - 3*x + assert hermite_prob(4, x) == x**4 - 6*x**2 + 3 + assert hermite_prob(6, x) == x**6 - 15*x**4 + 45*x**2 - 15 + + n = Symbol("n") + assert unchanged(hermite_prob, n, x) + assert hermite_prob(n, -x) == (-1)**n*hermite_prob(n, x) + assert unchanged(hermite_prob, -n, x) + + assert hermite_prob(n, 0) == sqrt(pi)/gamma(S.Half - n/2) + assert hermite_prob(n, oo) is oo + + assert conjugate(hermite_prob(n, x)) == hermite_prob(n, conjugate(x)) + + _k = Dummy('k') + assert hermite_prob(n, x).rewrite(Sum).dummy_eq(factorial(n) * + Sum((-S.Half)**_k * x**(n-2*_k) / (factorial(_k) * factorial(n-2*_k)), + (_k, 0, floor(n/2)))) + assert hermite_prob(n, x).rewrite("polynomial").dummy_eq(factorial(n) * + Sum((-S.Half)**_k * x**(n-2*_k) / (factorial(_k) * factorial(n-2*_k)), + (_k, 0, floor(n/2)))) + + assert diff(hermite_prob(n, x), x) == n*hermite_prob(n-1, x) + assert diff(hermite_prob(n, x), n) == Derivative(hermite_prob(n, x), n) + raises(ArgumentIndexError, lambda: hermite_prob(n, x).fdiff(3)) + + assert hermite_prob(n, x).rewrite(hermite) == \ + sqrt(2)**(-n) * hermite(n, x/sqrt(2)) + + +def test_laguerre(): + n = Symbol("n") + m = Symbol("m", negative=True) + + # Laguerre polynomials: + assert laguerre(0, x) == 1 + assert laguerre(1, x) == -x + 1 + assert laguerre(2, x) == x**2/2 - 2*x + 1 + assert laguerre(3, x) == -x**3/6 + 3*x**2/2 - 3*x + 1 + assert laguerre(-2, x) == (x + 1)*exp(x) + + X = laguerre(n, x) + assert isinstance(X, laguerre) + + assert laguerre(n, 0) == 1 + assert laguerre(n, oo) == (-1)**n*oo + assert laguerre(n, -oo) is oo + + assert conjugate(laguerre(n, x)) == laguerre(n, conjugate(x)) + + _k = Dummy('k') + + assert laguerre(n, x).rewrite(Sum).dummy_eq( + Sum(x**_k*RisingFactorial(-n, _k)/factorial(_k)**2, (_k, 0, n))) + assert laguerre(n, x).rewrite("polynomial").dummy_eq( + Sum(x**_k*RisingFactorial(-n, _k)/factorial(_k)**2, (_k, 0, n))) + assert laguerre(m, x).rewrite(Sum).dummy_eq( + exp(x)*Sum((-x)**_k*RisingFactorial(m + 1, _k)/factorial(_k)**2, + (_k, 0, -m - 1))) + assert laguerre(m, x).rewrite("polynomial").dummy_eq( + exp(x)*Sum((-x)**_k*RisingFactorial(m + 1, _k)/factorial(_k)**2, + (_k, 0, -m - 1))) + + assert diff(laguerre(n, x), x) == -assoc_laguerre(n - 1, 1, x) + + k = Symbol('k') + assert laguerre(-n, x) == exp(x)*laguerre(n - 1, -x) + assert laguerre(-3, x) == exp(x)*laguerre(2, -x) + assert unchanged(laguerre, -n + k, x) + + raises(ValueError, lambda: laguerre(-2.1, x)) + raises(ValueError, lambda: laguerre(Rational(5, 2), x)) + raises(ArgumentIndexError, lambda: laguerre(n, x).fdiff(1)) + raises(ArgumentIndexError, lambda: laguerre(n, x).fdiff(3)) + + +def test_assoc_laguerre(): + n = Symbol("n") + m = Symbol("m") + alpha = Symbol("alpha") + + # generalized Laguerre polynomials: + assert assoc_laguerre(0, alpha, x) == 1 + assert assoc_laguerre(1, alpha, x) == -x + alpha + 1 + assert assoc_laguerre(2, alpha, x).expand() == \ + (x**2/2 - (alpha + 2)*x + (alpha + 2)*(alpha + 1)/2).expand() + assert assoc_laguerre(3, alpha, x).expand() == \ + (-x**3/6 + (alpha + 3)*x**2/2 - (alpha + 2)*(alpha + 3)*x/2 + + (alpha + 1)*(alpha + 2)*(alpha + 3)/6).expand() + + # Test the lowest 10 polynomials with laguerre_poly, to make sure it works: + for i in range(10): + assert assoc_laguerre(i, 0, x).expand() == laguerre_poly(i, x) + + X = assoc_laguerre(n, m, x) + assert isinstance(X, assoc_laguerre) + + assert assoc_laguerre(n, 0, x) == laguerre(n, x) + assert assoc_laguerre(n, alpha, 0) == binomial(alpha + n, alpha) + p = Symbol("p", positive=True) + assert assoc_laguerre(p, alpha, oo) == (-1)**p*oo + assert assoc_laguerre(p, alpha, -oo) is oo + + assert diff(assoc_laguerre(n, alpha, x), x) == \ + -assoc_laguerre(n - 1, alpha + 1, x) + _k = Dummy('k') + assert diff(assoc_laguerre(n, alpha, x), alpha).dummy_eq( + Sum(assoc_laguerre(_k, alpha, x)/(-alpha + n), (_k, 0, n - 1))) + + assert conjugate(assoc_laguerre(n, alpha, x)) == \ + assoc_laguerre(n, conjugate(alpha), conjugate(x)) + + assert assoc_laguerre(n, alpha, x).rewrite(Sum).dummy_eq( + gamma(alpha + n + 1)*Sum(x**_k*RisingFactorial(-n, _k)/ + (factorial(_k)*gamma(_k + alpha + 1)), (_k, 0, n))/factorial(n)) + assert assoc_laguerre(n, alpha, x).rewrite("polynomial").dummy_eq( + gamma(alpha + n + 1)*Sum(x**_k*RisingFactorial(-n, _k)/ + (factorial(_k)*gamma(_k + alpha + 1)), (_k, 0, n))/factorial(n)) + raises(ValueError, lambda: assoc_laguerre(-2.1, alpha, x)) + raises(ArgumentIndexError, lambda: assoc_laguerre(n, alpha, x).fdiff(1)) + raises(ArgumentIndexError, lambda: assoc_laguerre(n, alpha, x).fdiff(4)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_spherical_harmonics.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_spherical_harmonics.py new file mode 100644 index 0000000000000000000000000000000000000000..2e0d4ffebabb62c13d3fc2996e8ba23866467720 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_spherical_harmonics.py @@ -0,0 +1,66 @@ +from sympy.core.function import diff +from sympy.core.numbers import (I, pi) +from sympy.core.symbol import Symbol +from sympy.functions.elementary.complexes import conjugate +from sympy.functions.elementary.exponential import exp +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (cos, cot, sin) +from sympy.functions.special.spherical_harmonics import Ynm, Znm, Ynm_c + + +def test_Ynm(): + # https://en.wikipedia.org/wiki/Spherical_harmonics + th, ph = Symbol("theta", real=True), Symbol("phi", real=True) + from sympy.abc import n,m + + assert Ynm(0, 0, th, ph).expand(func=True) == 1/(2*sqrt(pi)) + assert Ynm(1, -1, th, ph) == -exp(-2*I*ph)*Ynm(1, 1, th, ph) + assert Ynm(1, -1, th, ph).expand(func=True) == sqrt(6)*sin(th)*exp(-I*ph)/(4*sqrt(pi)) + assert Ynm(1, 0, th, ph).expand(func=True) == sqrt(3)*cos(th)/(2*sqrt(pi)) + assert Ynm(1, 1, th, ph).expand(func=True) == -sqrt(6)*sin(th)*exp(I*ph)/(4*sqrt(pi)) + assert Ynm(2, 0, th, ph).expand(func=True) == 3*sqrt(5)*cos(th)**2/(4*sqrt(pi)) - sqrt(5)/(4*sqrt(pi)) + assert Ynm(2, 1, th, ph).expand(func=True) == -sqrt(30)*sin(th)*exp(I*ph)*cos(th)/(4*sqrt(pi)) + assert Ynm(2, -2, th, ph).expand(func=True) == (-sqrt(30)*exp(-2*I*ph)*cos(th)**2/(8*sqrt(pi)) + + sqrt(30)*exp(-2*I*ph)/(8*sqrt(pi))) + assert Ynm(2, 2, th, ph).expand(func=True) == (-sqrt(30)*exp(2*I*ph)*cos(th)**2/(8*sqrt(pi)) + + sqrt(30)*exp(2*I*ph)/(8*sqrt(pi))) + + assert diff(Ynm(n, m, th, ph), th) == (m*cot(th)*Ynm(n, m, th, ph) + + sqrt((-m + n)*(m + n + 1))*exp(-I*ph)*Ynm(n, m + 1, th, ph)) + assert diff(Ynm(n, m, th, ph), ph) == I*m*Ynm(n, m, th, ph) + + assert conjugate(Ynm(n, m, th, ph)) == (-1)**(2*m)*exp(-2*I*m*ph)*Ynm(n, m, th, ph) + + assert Ynm(n, m, -th, ph) == Ynm(n, m, th, ph) + assert Ynm(n, m, th, -ph) == exp(-2*I*m*ph)*Ynm(n, m, th, ph) + assert Ynm(n, -m, th, ph) == (-1)**m*exp(-2*I*m*ph)*Ynm(n, m, th, ph) + + +def test_Ynm_c(): + th, ph = Symbol("theta", real=True), Symbol("phi", real=True) + from sympy.abc import n,m + + assert Ynm_c(n, m, th, ph) == (-1)**(2*m)*exp(-2*I*m*ph)*Ynm(n, m, th, ph) + + +def test_Znm(): + # https://en.wikipedia.org/wiki/Solid_harmonics#List_of_lowest_functions + th, ph = Symbol("theta", real=True), Symbol("phi", real=True) + + assert Znm(0, 0, th, ph) == Ynm(0, 0, th, ph) + assert Znm(1, -1, th, ph) == (-sqrt(2)*I*(Ynm(1, 1, th, ph) + - exp(-2*I*ph)*Ynm(1, 1, th, ph))/2) + assert Znm(1, 0, th, ph) == Ynm(1, 0, th, ph) + assert Znm(1, 1, th, ph) == (sqrt(2)*(Ynm(1, 1, th, ph) + + exp(-2*I*ph)*Ynm(1, 1, th, ph))/2) + assert Znm(0, 0, th, ph).expand(func=True) == 1/(2*sqrt(pi)) + assert Znm(1, -1, th, ph).expand(func=True) == (sqrt(3)*I*sin(th)*exp(I*ph)/(4*sqrt(pi)) + - sqrt(3)*I*sin(th)*exp(-I*ph)/(4*sqrt(pi))) + assert Znm(1, 0, th, ph).expand(func=True) == sqrt(3)*cos(th)/(2*sqrt(pi)) + assert Znm(1, 1, th, ph).expand(func=True) == (-sqrt(3)*sin(th)*exp(I*ph)/(4*sqrt(pi)) + - sqrt(3)*sin(th)*exp(-I*ph)/(4*sqrt(pi))) + assert Znm(2, -1, th, ph).expand(func=True) == (sqrt(15)*I*sin(th)*exp(I*ph)*cos(th)/(4*sqrt(pi)) + - sqrt(15)*I*sin(th)*exp(-I*ph)*cos(th)/(4*sqrt(pi))) + assert Znm(2, 0, th, ph).expand(func=True) == 3*sqrt(5)*cos(th)**2/(4*sqrt(pi)) - sqrt(5)/(4*sqrt(pi)) + assert Znm(2, 1, th, ph).expand(func=True) == (-sqrt(15)*sin(th)*exp(I*ph)*cos(th)/(4*sqrt(pi)) + - sqrt(15)*sin(th)*exp(-I*ph)*cos(th)/(4*sqrt(pi))) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_tensor_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_tensor_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..7d4f31c45ae0a60a6f72dc5551794b2110f5ab99 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_tensor_functions.py @@ -0,0 +1,145 @@ +from sympy.core.relational import Ne +from sympy.core.symbol import (Dummy, Symbol, symbols) +from sympy.functions.elementary.complexes import (adjoint, conjugate, transpose) +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.special.tensor_functions import (Eijk, KroneckerDelta, LeviCivita) + +from sympy.physics.secondquant import evaluate_deltas, F + +x, y = symbols('x y') + + +def test_levicivita(): + assert Eijk(1, 2, 3) == LeviCivita(1, 2, 3) + assert LeviCivita(1, 2, 3) == 1 + assert LeviCivita(int(1), int(2), int(3)) == 1 + assert LeviCivita(1, 3, 2) == -1 + assert LeviCivita(1, 2, 2) == 0 + i, j, k = symbols('i j k') + assert LeviCivita(i, j, k) == LeviCivita(i, j, k, evaluate=False) + assert LeviCivita(i, j, i) == 0 + assert LeviCivita(1, i, i) == 0 + assert LeviCivita(i, j, k).doit() == (j - i)*(k - i)*(k - j)/2 + assert LeviCivita(1, 2, 3, 1) == 0 + assert LeviCivita(4, 5, 1, 2, 3) == 1 + assert LeviCivita(4, 5, 2, 1, 3) == -1 + + assert LeviCivita(i, j, k).is_integer is True + + assert adjoint(LeviCivita(i, j, k)) == LeviCivita(i, j, k) + assert conjugate(LeviCivita(i, j, k)) == LeviCivita(i, j, k) + assert transpose(LeviCivita(i, j, k)) == LeviCivita(i, j, k) + + +def test_kronecker_delta(): + i, j = symbols('i j') + k = Symbol('k', nonzero=True) + assert KroneckerDelta(1, 1) == 1 + assert KroneckerDelta(1, 2) == 0 + assert KroneckerDelta(k, 0) == 0 + assert KroneckerDelta(x, x) == 1 + assert KroneckerDelta(x**2 - y**2, x**2 - y**2) == 1 + assert KroneckerDelta(i, i) == 1 + assert KroneckerDelta(i, i + 1) == 0 + assert KroneckerDelta(0, 0) == 1 + assert KroneckerDelta(0, 1) == 0 + assert KroneckerDelta(i + k, i) == 0 + assert KroneckerDelta(i + k, i + k) == 1 + assert KroneckerDelta(i + k, i + 1 + k) == 0 + assert KroneckerDelta(i, j).subs({"i": 1, "j": 0}) == 0 + assert KroneckerDelta(i, j).subs({"i": 3, "j": 3}) == 1 + + assert KroneckerDelta(i, j)**0 == 1 + for n in range(1, 10): + assert KroneckerDelta(i, j)**n == KroneckerDelta(i, j) + assert KroneckerDelta(i, j)**-n == 1/KroneckerDelta(i, j) + + assert KroneckerDelta(i, j).is_integer is True + + assert adjoint(KroneckerDelta(i, j)) == KroneckerDelta(i, j) + assert conjugate(KroneckerDelta(i, j)) == KroneckerDelta(i, j) + assert transpose(KroneckerDelta(i, j)) == KroneckerDelta(i, j) + # to test if canonical + assert (KroneckerDelta(i, j) == KroneckerDelta(j, i)) == True + + assert KroneckerDelta(i, j).rewrite(Piecewise) == Piecewise((0, Ne(i, j)), (1, True)) + + # Tests with range: + assert KroneckerDelta(i, j, (0, i)).args == (i, j, (0, i)) + assert KroneckerDelta(i, j, (-j, i)).delta_range == (-j, i) + + # If index is out of range, return zero: + assert KroneckerDelta(i, j, (0, i-1)) == 0 + assert KroneckerDelta(-1, j, (0, i-1)) == 0 + assert KroneckerDelta(j, -1, (0, i-1)) == 0 + assert KroneckerDelta(j, i, (0, i-1)) == 0 + + +def test_kronecker_delta_secondquant(): + """secondquant-specific methods""" + D = KroneckerDelta + i, j, v, w = symbols('i j v w', below_fermi=True, cls=Dummy) + a, b, t, u = symbols('a b t u', above_fermi=True, cls=Dummy) + p, q, r, s = symbols('p q r s', cls=Dummy) + + assert D(i, a) == 0 + assert D(i, t) == 0 + + assert D(i, j).is_above_fermi is False + assert D(a, b).is_above_fermi is True + assert D(p, q).is_above_fermi is True + assert D(i, q).is_above_fermi is False + assert D(q, i).is_above_fermi is False + assert D(q, v).is_above_fermi is False + assert D(a, q).is_above_fermi is True + + assert D(i, j).is_below_fermi is True + assert D(a, b).is_below_fermi is False + assert D(p, q).is_below_fermi is True + assert D(p, j).is_below_fermi is True + assert D(q, b).is_below_fermi is False + + assert D(i, j).is_only_above_fermi is False + assert D(a, b).is_only_above_fermi is True + assert D(p, q).is_only_above_fermi is False + assert D(i, q).is_only_above_fermi is False + assert D(q, i).is_only_above_fermi is False + assert D(a, q).is_only_above_fermi is True + + assert D(i, j).is_only_below_fermi is True + assert D(a, b).is_only_below_fermi is False + assert D(p, q).is_only_below_fermi is False + assert D(p, j).is_only_below_fermi is True + assert D(q, b).is_only_below_fermi is False + + assert not D(i, q).indices_contain_equal_information + assert not D(a, q).indices_contain_equal_information + assert D(p, q).indices_contain_equal_information + assert D(a, b).indices_contain_equal_information + assert D(i, j).indices_contain_equal_information + + assert D(q, b).preferred_index == b + assert D(q, b).killable_index == q + assert D(q, t).preferred_index == t + assert D(q, t).killable_index == q + assert D(q, i).preferred_index == i + assert D(q, i).killable_index == q + assert D(q, v).preferred_index == v + assert D(q, v).killable_index == q + assert D(q, p).preferred_index == p + assert D(q, p).killable_index == q + + EV = evaluate_deltas + assert EV(D(a, q)*F(q)) == F(a) + assert EV(D(i, q)*F(q)) == F(i) + assert EV(D(a, q)*F(a)) == D(a, q)*F(a) + assert EV(D(i, q)*F(i)) == D(i, q)*F(i) + assert EV(D(a, b)*F(a)) == F(b) + assert EV(D(a, b)*F(b)) == F(a) + assert EV(D(i, j)*F(i)) == F(j) + assert EV(D(i, j)*F(j)) == F(i) + assert EV(D(p, q)*F(q)) == F(p) + assert EV(D(p, q)*F(p)) == F(q) + assert EV(D(p, j)*D(p, i)*F(i)) == F(j) + assert EV(D(p, j)*D(p, i)*F(j)) == F(i) + assert EV(D(p, q)*D(p, i))*F(i) == D(q, i)*F(i) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_zeta_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_zeta_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..c2083b0b6e8cb38fde17fb1ede2a34be6338b1dc --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/tests/test_zeta_functions.py @@ -0,0 +1,286 @@ +from sympy.concrete.summations import Sum +from sympy.core.function import expand_func +from sympy.core.numbers import (Float, I, Rational, nan, oo, pi, zoo) +from sympy.core.singleton import S +from sympy.core.symbol import Symbol +from sympy.functions.elementary.complexes import (Abs, polar_lift) +from sympy.functions.elementary.exponential import (exp, exp_polar, log) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.special.zeta_functions import (dirichlet_eta, lerchphi, polylog, riemann_xi, stieltjes, zeta) +from sympy.series.order import O +from sympy.core.function import ArgumentIndexError +from sympy.functions.combinatorial.numbers import bernoulli, factorial, genocchi, harmonic +from sympy.testing.pytest import raises +from sympy.core.random import (test_derivative_numerically as td, + random_complex_number as randcplx, verify_numerically) + +x = Symbol('x') +a = Symbol('a') +b = Symbol('b', negative=True) +z = Symbol('z') +s = Symbol('s') + + +def test_zeta_eval(): + + assert zeta(nan) is nan + assert zeta(x, nan) is nan + + assert zeta(0) == Rational(-1, 2) + assert zeta(0, x) == S.Half - x + assert zeta(0, b) == S.Half - b + + assert zeta(1) is zoo + assert zeta(1, 2) is zoo + assert zeta(1, -7) is zoo + assert zeta(1, x) is zoo + + assert zeta(2, 1) == pi**2/6 + assert zeta(3, 1) == zeta(3) + + assert zeta(2) == pi**2/6 + assert zeta(4) == pi**4/90 + assert zeta(6) == pi**6/945 + + assert zeta(4, 3) == pi**4/90 - Rational(17, 16) + assert zeta(7, 4) == zeta(7) - Rational(282251, 279936) + assert zeta(S.Half, 2).func == zeta + assert expand_func(zeta(S.Half, 2)) == zeta(S.Half) - 1 + assert zeta(x, 3).func == zeta + assert expand_func(zeta(x, 3)) == zeta(x) - 1 - 1/2**x + + assert zeta(2, 0) is nan + assert zeta(3, -1) is nan + assert zeta(4, -2) is nan + + assert zeta(oo) == 1 + + assert zeta(-1) == Rational(-1, 12) + assert zeta(-2) == 0 + assert zeta(-3) == Rational(1, 120) + assert zeta(-4) == 0 + assert zeta(-5) == Rational(-1, 252) + + assert zeta(-1, 3) == Rational(-37, 12) + assert zeta(-1, 7) == Rational(-253, 12) + assert zeta(-1, -4) == Rational(-121, 12) + assert zeta(-1, -9) == Rational(-541, 12) + + assert zeta(-4, 3) == -17 + assert zeta(-4, -8) == 8772 + + assert zeta(0, 1) == Rational(-1, 2) + assert zeta(0, -1) == Rational(3, 2) + + assert zeta(0, 2) == Rational(-3, 2) + assert zeta(0, -2) == Rational(5, 2) + + assert zeta( + 3).evalf(20).epsilon_eq(Float("1.2020569031595942854", 20), 1e-19) + + +def test_zeta_series(): + assert zeta(x, a).series(a, z, 2) == \ + zeta(x, z) - x*(a-z)*zeta(x+1, z) + O((a-z)**2, (a, z)) + + +def test_dirichlet_eta_eval(): + assert dirichlet_eta(0) == S.Half + assert dirichlet_eta(-1) == Rational(1, 4) + assert dirichlet_eta(1) == log(2) + assert dirichlet_eta(1, S.Half).simplify() == pi/2 + assert dirichlet_eta(1, 2) == 1 - log(2) + assert dirichlet_eta(2) == pi**2/12 + assert dirichlet_eta(4) == pi**4*Rational(7, 720) + assert str(dirichlet_eta(I).evalf(n=10)) == '0.5325931818 + 0.2293848577*I' + assert str(dirichlet_eta(I, I).evalf(n=10)) == '3.462349253 + 0.220285771*I' + + +def test_riemann_xi_eval(): + assert riemann_xi(2) == pi/6 + assert riemann_xi(0) == Rational(1, 2) + assert riemann_xi(1) == Rational(1, 2) + assert riemann_xi(3).rewrite(zeta) == 3*zeta(3)/(2*pi) + assert riemann_xi(4) == pi**2/15 + + +def test_rewriting(): + from sympy.functions.elementary.piecewise import Piecewise + assert isinstance(dirichlet_eta(x).rewrite(zeta), Piecewise) + assert isinstance(dirichlet_eta(x).rewrite(genocchi), Piecewise) + assert zeta(x).rewrite(dirichlet_eta) == dirichlet_eta(x)/(1 - 2**(1 - x)) + assert zeta(x).rewrite(dirichlet_eta, a=2) == zeta(x) + assert verify_numerically(dirichlet_eta(x), dirichlet_eta(x).rewrite(zeta), x) + assert verify_numerically(dirichlet_eta(x), dirichlet_eta(x).rewrite(genocchi), x) + assert verify_numerically(zeta(x), zeta(x).rewrite(dirichlet_eta), x) + + assert zeta(x, a).rewrite(lerchphi) == lerchphi(1, x, a) + assert polylog(s, z).rewrite(lerchphi) == lerchphi(z, s, 1)*z + + assert lerchphi(1, x, a).rewrite(zeta) == zeta(x, a) + assert z*lerchphi(z, s, 1).rewrite(polylog) == polylog(s, z) + + +def test_derivatives(): + from sympy.core.function import Derivative + assert zeta(x, a).diff(x) == Derivative(zeta(x, a), x) + assert zeta(x, a).diff(a) == -x*zeta(x + 1, a) + assert lerchphi( + z, s, a).diff(z) == (lerchphi(z, s - 1, a) - a*lerchphi(z, s, a))/z + assert lerchphi(z, s, a).diff(a) == -s*lerchphi(z, s + 1, a) + assert polylog(s, z).diff(z) == polylog(s - 1, z)/z + + b = randcplx() + c = randcplx() + assert td(zeta(b, x), x) + assert td(polylog(b, z), z) + assert td(lerchphi(c, b, x), x) + assert td(lerchphi(x, b, c), x) + raises(ArgumentIndexError, lambda: lerchphi(c, b, x).fdiff(2)) + raises(ArgumentIndexError, lambda: lerchphi(c, b, x).fdiff(4)) + raises(ArgumentIndexError, lambda: polylog(b, z).fdiff(1)) + raises(ArgumentIndexError, lambda: polylog(b, z).fdiff(3)) + + +def myexpand(func, target): + expanded = expand_func(func) + if target is not None: + return expanded == target + if expanded == func: # it didn't expand + return False + + # check to see that the expanded and original evaluate to the same value + subs = {} + for a in func.free_symbols: + subs[a] = randcplx() + return abs(func.subs(subs).n() + - expanded.replace(exp_polar, exp).subs(subs).n()) < 1e-10 + + +def test_polylog_expansion(): + assert polylog(s, 0) == 0 + assert polylog(s, 1) == zeta(s) + assert polylog(s, -1) == -dirichlet_eta(s) + assert polylog(s, exp_polar(I*pi*Rational(4, 3))) == polylog(s, exp(I*pi*Rational(4, 3))) + assert polylog(s, exp_polar(I*pi)/3) == polylog(s, exp(I*pi)/3) + + assert myexpand(polylog(1, z), -log(1 - z)) + assert myexpand(polylog(0, z), z/(1 - z)) + assert myexpand(polylog(-1, z), z/(1 - z)**2) + assert ((1-z)**3 * expand_func(polylog(-2, z))).simplify() == z*(1 + z) + assert myexpand(polylog(-5, z), None) + + +def test_polylog_series(): + assert polylog(1, z).series(z, n=5) == z + z**2/2 + z**3/3 + z**4/4 + O(z**5) + assert polylog(1, sqrt(z)).series(z, n=3) == z/2 + z**2/4 + sqrt(z)\ + + z**(S(3)/2)/3 + z**(S(5)/2)/5 + O(z**3) + + # https://github.com/sympy/sympy/issues/9497 + assert polylog(S(3)/2, -z).series(z, 0, 5) == -z + sqrt(2)*z**2/4\ + - sqrt(3)*z**3/9 + z**4/8 + O(z**5) + + +def test_issue_8404(): + i = Symbol('i', integer=True) + assert Abs(Sum(1/(3*i + 1)**2, (i, 0, S.Infinity)).doit().n(4) + - 1.122) < 0.001 + + +def test_polylog_values(): + assert polylog(2, 2) == pi**2/4 - I*pi*log(2) + assert polylog(2, S.Half) == pi**2/12 - log(2)**2/2 + for z in [S.Half, 2, (sqrt(5)-1)/2, -(sqrt(5)-1)/2, -(sqrt(5)+1)/2, (3-sqrt(5))/2]: + assert Abs(polylog(2, z).evalf() - polylog(2, z, evaluate=False).evalf()) < 1e-15 + z = Symbol("z") + for s in [-1, 0]: + for _ in range(10): + assert verify_numerically(polylog(s, z), polylog(s, z, evaluate=False), + z, a=-3, b=-2, c=S.Half, d=2) + assert verify_numerically(polylog(s, z), polylog(s, z, evaluate=False), + z, a=2, b=-2, c=5, d=2) + + from sympy.integrals.integrals import Integral + assert polylog(0, Integral(1, (x, 0, 1))) == -S.Half + + +def test_lerchphi_expansion(): + assert myexpand(lerchphi(1, s, a), zeta(s, a)) + assert myexpand(lerchphi(z, s, 1), polylog(s, z)/z) + + # direct summation + assert myexpand(lerchphi(z, -1, a), a/(1 - z) + z/(1 - z)**2) + assert myexpand(lerchphi(z, -3, a), None) + # polylog reduction + assert myexpand(lerchphi(z, s, S.Half), + 2**(s - 1)*(polylog(s, sqrt(z))/sqrt(z) + - polylog(s, polar_lift(-1)*sqrt(z))/sqrt(z))) + assert myexpand(lerchphi(z, s, 2), -1/z + polylog(s, z)/z**2) + assert myexpand(lerchphi(z, s, Rational(3, 2)), None) + assert myexpand(lerchphi(z, s, Rational(7, 3)), None) + assert myexpand(lerchphi(z, s, Rational(-1, 3)), None) + assert myexpand(lerchphi(z, s, Rational(-5, 2)), None) + + # hurwitz zeta reduction + assert myexpand(lerchphi(-1, s, a), + 2**(-s)*zeta(s, a/2) - 2**(-s)*zeta(s, (a + 1)/2)) + assert myexpand(lerchphi(I, s, a), None) + assert myexpand(lerchphi(-I, s, a), None) + assert myexpand(lerchphi(exp(I*pi*Rational(2, 5)), s, a), None) + + +def test_stieltjes(): + assert isinstance(stieltjes(x), stieltjes) + assert isinstance(stieltjes(x, a), stieltjes) + + # Zero'th constant EulerGamma + assert stieltjes(0) == S.EulerGamma + assert stieltjes(0, 1) == S.EulerGamma + + # Not defined + assert stieltjes(nan) is nan + assert stieltjes(0, nan) is nan + assert stieltjes(-1) is S.ComplexInfinity + assert stieltjes(1.5) is S.ComplexInfinity + assert stieltjes(z, 0) is S.ComplexInfinity + assert stieltjes(z, -1) is S.ComplexInfinity + + +def test_stieltjes_evalf(): + assert abs(stieltjes(0).evalf() - 0.577215664) < 1E-9 + assert abs(stieltjes(0, 0.5).evalf() - 1.963510026) < 1E-9 + assert abs(stieltjes(1, 2).evalf() + 0.072815845) < 1E-9 + + +def test_issue_10475(): + a = Symbol('a', extended_real=True) + b = Symbol('b', extended_positive=True) + s = Symbol('s', zero=False) + + assert zeta(2 + I).is_finite + assert zeta(1).is_finite is False + assert zeta(x).is_finite is None + assert zeta(x + I).is_finite is None + assert zeta(a).is_finite is None + assert zeta(b).is_finite is None + assert zeta(-b).is_finite is True + assert zeta(b**2 - 2*b + 1).is_finite is None + assert zeta(a + I).is_finite is True + assert zeta(b + 1).is_finite is True + assert zeta(s + 1).is_finite is True + + +def test_issue_14177(): + n = Symbol('n', nonnegative=True, integer=True) + + assert zeta(-n).rewrite(bernoulli) == bernoulli(n+1) / (-n-1) + assert zeta(-n, a).rewrite(bernoulli) == bernoulli(n+1, a) / (-n-1) + z2n = -(2*I*pi)**(2*n)*bernoulli(2*n) / (2*factorial(2*n)) + assert zeta(2*n).rewrite(bernoulli) == z2n + assert expand_func(zeta(s, n+1)) == zeta(s) - harmonic(n, s) + assert expand_func(zeta(-b, -n)) is nan + assert expand_func(zeta(-b, n)) == zeta(-b, n) + + n = Symbol('n') + + assert zeta(2*n) == zeta(2*n) # As sign of z (= 2*n) is not determined diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/zeta_functions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/zeta_functions.py new file mode 100644 index 0000000000000000000000000000000000000000..8f410f0f1086de91490c714cd3becf11df9ab189 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/functions/special/zeta_functions.py @@ -0,0 +1,786 @@ +""" Riemann zeta and related function. """ + +from sympy.core.add import Add +from sympy.core.cache import cacheit +from sympy.core.function import ArgumentIndexError, expand_mul, DefinedFunction +from sympy.core.logic import fuzzy_not +from sympy.core.numbers import pi, I, Integer +from sympy.core.relational import Eq +from sympy.core.singleton import S +from sympy.core.symbol import Dummy +from sympy.core.sympify import sympify +from sympy.functions.combinatorial.numbers import bernoulli, factorial, genocchi, harmonic +from sympy.functions.elementary.complexes import re, unpolarify, Abs, polar_lift +from sympy.functions.elementary.exponential import log, exp_polar, exp +from sympy.functions.elementary.integers import ceiling, floor +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise +from sympy.polys.polytools import Poly + +############################################################################### +###################### LERCH TRANSCENDENT ##################################### +############################################################################### + + +class lerchphi(DefinedFunction): + r""" + Lerch transcendent (Lerch phi function). + + Explanation + =========== + + For $\operatorname{Re}(a) > 0$, $|z| < 1$ and $s \in \mathbb{C}$, the + Lerch transcendent is defined as + + .. math :: \Phi(z, s, a) = \sum_{n=0}^\infty \frac{z^n}{(n + a)^s}, + + where the standard branch of the argument is used for $n + a$, + and by analytic continuation for other values of the parameters. + + A commonly used related function is the Lerch zeta function, defined by + + .. math:: L(q, s, a) = \Phi(e^{2\pi i q}, s, a). + + **Analytic Continuation and Branching Behavior** + + It can be shown that + + .. math:: \Phi(z, s, a) = z\Phi(z, s, a+1) + a^{-s}. + + This provides the analytic continuation to $\operatorname{Re}(a) \le 0$. + + Assume now $\operatorname{Re}(a) > 0$. The integral representation + + .. math:: \Phi_0(z, s, a) = \int_0^\infty \frac{t^{s-1} e^{-at}}{1 - ze^{-t}} + \frac{\mathrm{d}t}{\Gamma(s)} + + provides an analytic continuation to $\mathbb{C} - [1, \infty)$. + Finally, for $x \in (1, \infty)$ we find + + .. math:: \lim_{\epsilon \to 0^+} \Phi_0(x + i\epsilon, s, a) + -\lim_{\epsilon \to 0^+} \Phi_0(x - i\epsilon, s, a) + = \frac{2\pi i \log^{s-1}{x}}{x^a \Gamma(s)}, + + using the standard branch for both $\log{x}$ and + $\log{\log{x}}$ (a branch of $\log{\log{x}}$ is needed to + evaluate $\log{x}^{s-1}$). + This concludes the analytic continuation. The Lerch transcendent is thus + branched at $z \in \{0, 1, \infty\}$ and + $a \in \mathbb{Z}_{\le 0}$. For fixed $z, a$ outside these + branch points, it is an entire function of $s$. + + Examples + ======== + + The Lerch transcendent is a fairly general function, for this reason it does + not automatically evaluate to simpler functions. Use ``expand_func()`` to + achieve this. + + If $z=1$, the Lerch transcendent reduces to the Hurwitz zeta function: + + >>> from sympy import lerchphi, expand_func + >>> from sympy.abc import z, s, a + >>> expand_func(lerchphi(1, s, a)) + zeta(s, a) + + More generally, if $z$ is a root of unity, the Lerch transcendent + reduces to a sum of Hurwitz zeta functions: + + >>> expand_func(lerchphi(-1, s, a)) + zeta(s, a/2)/2**s - zeta(s, a/2 + 1/2)/2**s + + If $a=1$, the Lerch transcendent reduces to the polylogarithm: + + >>> expand_func(lerchphi(z, s, 1)) + polylog(s, z)/z + + More generally, if $a$ is rational, the Lerch transcendent reduces + to a sum of polylogarithms: + + >>> from sympy import S + >>> expand_func(lerchphi(z, s, S(1)/2)) + 2**(s - 1)*(polylog(s, sqrt(z))/sqrt(z) - + polylog(s, sqrt(z)*exp_polar(I*pi))/sqrt(z)) + >>> expand_func(lerchphi(z, s, S(3)/2)) + -2**s/z + 2**(s - 1)*(polylog(s, sqrt(z))/sqrt(z) - + polylog(s, sqrt(z)*exp_polar(I*pi))/sqrt(z))/z + + The derivatives with respect to $z$ and $a$ can be computed in + closed form: + + >>> lerchphi(z, s, a).diff(z) + (-a*lerchphi(z, s, a) + lerchphi(z, s - 1, a))/z + >>> lerchphi(z, s, a).diff(a) + -s*lerchphi(z, s + 1, a) + + See Also + ======== + + polylog, zeta + + References + ========== + + .. [1] Bateman, H.; Erdelyi, A. (1953), Higher Transcendental Functions, + Vol. I, New York: McGraw-Hill. Section 1.11. + .. [2] https://dlmf.nist.gov/25.14 + .. [3] https://en.wikipedia.org/wiki/Lerch_transcendent + + """ + + def _eval_expand_func(self, **hints): + z, s, a = self.args + if z == 1: + return zeta(s, a) + if s.is_Integer and s <= 0: + t = Dummy('t') + p = Poly((t + a)**(-s), t) + start = 1/(1 - t) + res = S.Zero + for c in reversed(p.all_coeffs()): + res += c*start + start = t*start.diff(t) + return res.subs(t, z) + + if a.is_Rational: + # See section 18 of + # Kelly B. Roach. Hypergeometric Function Representations. + # In: Proceedings of the 1997 International Symposium on Symbolic and + # Algebraic Computation, pages 205-211, New York, 1997. ACM. + # TODO should something be polarified here? + add = S.Zero + mul = S.One + # First reduce a to the interaval (0, 1] + if a > 1: + n = floor(a) + if n == a: + n -= 1 + a -= n + mul = z**(-n) + add = Add(*[-z**(k - n)/(a + k)**s for k in range(n)]) + elif a <= 0: + n = floor(-a) + 1 + a += n + mul = z**n + add = Add(*[z**(n - 1 - k)/(a - k - 1)**s for k in range(n)]) + + m, n = S([a.p, a.q]) + zet = exp_polar(2*pi*I/n) + root = z**(1/n) + up_zet = unpolarify(zet) + addargs = [] + for k in range(n): + p = polylog(s, zet**k*root) + if isinstance(p, polylog): + p = p._eval_expand_func(**hints) + addargs.append(p/(up_zet**k*root)**m) + return add + mul*n**(s - 1)*Add(*addargs) + + # TODO use minpoly instead of ad-hoc methods when issue 5888 is fixed + if isinstance(z, exp) and (z.args[0]/(pi*I)).is_Rational or z in [-1, I, -I]: + # TODO reference? + if z == -1: + p, q = S([1, 2]) + elif z == I: + p, q = S([1, 4]) + elif z == -I: + p, q = S([-1, 4]) + else: + arg = z.args[0]/(2*pi*I) + p, q = S([arg.p, arg.q]) + return Add(*[exp(2*pi*I*k*p/q)/q**s*zeta(s, (k + a)/q) + for k in range(q)]) + + return lerchphi(z, s, a) + + def fdiff(self, argindex=1): + z, s, a = self.args + if argindex == 3: + return -s*lerchphi(z, s + 1, a) + elif argindex == 1: + return (lerchphi(z, s - 1, a) - a*lerchphi(z, s, a))/z + else: + raise ArgumentIndexError + + def _eval_rewrite_helper(self, target): + res = self._eval_expand_func() + if res.has(target): + return res + else: + return self + + def _eval_rewrite_as_zeta(self, z, s, a, **kwargs): + return self._eval_rewrite_helper(zeta) + + def _eval_rewrite_as_polylog(self, z, s, a, **kwargs): + return self._eval_rewrite_helper(polylog) + +############################################################################### +###################### POLYLOGARITHM ########################################## +############################################################################### + + +class polylog(DefinedFunction): + r""" + Polylogarithm function. + + Explanation + =========== + + For $|z| < 1$ and $s \in \mathbb{C}$, the polylogarithm is + defined by + + .. math:: \operatorname{Li}_s(z) = \sum_{n=1}^\infty \frac{z^n}{n^s}, + + where the standard branch of the argument is used for $n$. It admits + an analytic continuation which is branched at $z=1$ (notably not on the + sheet of initial definition), $z=0$ and $z=\infty$. + + The name polylogarithm comes from the fact that for $s=1$, the + polylogarithm is related to the ordinary logarithm (see examples), and that + + .. math:: \operatorname{Li}_{s+1}(z) = + \int_0^z \frac{\operatorname{Li}_s(t)}{t} \mathrm{d}t. + + The polylogarithm is a special case of the Lerch transcendent: + + .. math:: \operatorname{Li}_{s}(z) = z \Phi(z, s, 1). + + Examples + ======== + + For $z \in \{0, 1, -1\}$, the polylogarithm is automatically expressed + using other functions: + + >>> from sympy import polylog + >>> from sympy.abc import s + >>> polylog(s, 0) + 0 + >>> polylog(s, 1) + zeta(s) + >>> polylog(s, -1) + -dirichlet_eta(s) + + If $s$ is a negative integer, $0$ or $1$, the polylogarithm can be + expressed using elementary functions. This can be done using + ``expand_func()``: + + >>> from sympy import expand_func + >>> from sympy.abc import z + >>> expand_func(polylog(1, z)) + -log(1 - z) + >>> expand_func(polylog(0, z)) + z/(1 - z) + + The derivative with respect to $z$ can be computed in closed form: + + >>> polylog(s, z).diff(z) + polylog(s - 1, z)/z + + The polylogarithm can be expressed in terms of the lerch transcendent: + + >>> from sympy import lerchphi + >>> polylog(s, z).rewrite(lerchphi) + z*lerchphi(z, s, 1) + + See Also + ======== + + zeta, lerchphi + + """ + + @classmethod + def eval(cls, s, z): + if z.is_number: + if z is S.One: + return zeta(s) + elif z is S.NegativeOne: + return -dirichlet_eta(s) + elif z is S.Zero: + return S.Zero + elif s == 2: + dilogtable = _dilogtable() + if z in dilogtable: + return dilogtable[z] + + if z.is_zero: + return S.Zero + + # Make an effort to determine if z is 1 to avoid replacing into + # expression with singularity + zone = z.equals(S.One) + + if zone: + return zeta(s) + elif zone is False: + # For s = 0 or -1 use explicit formulas to evaluate, but + # automatically expanding polylog(1, z) to -log(1-z) seems + # undesirable for summation methods based on hypergeometric + # functions + if s is S.Zero: + return z/(1 - z) + elif s is S.NegativeOne: + return z/(1 - z)**2 + if s.is_zero: + return z/(1 - z) + + # polylog is branched, but not over the unit disk + if z.has(exp_polar, polar_lift) and (zone or (Abs(z) <= S.One) == True): + return cls(s, unpolarify(z)) + + def fdiff(self, argindex=1): + s, z = self.args + if argindex == 2: + return polylog(s - 1, z)/z + raise ArgumentIndexError + + def _eval_rewrite_as_lerchphi(self, s, z, **kwargs): + return z*lerchphi(z, s, 1) + + def _eval_expand_func(self, **hints): + s, z = self.args + if s == 1: + return -log(1 - z) + if s.is_Integer and s <= 0: + u = Dummy('u') + start = u/(1 - u) + for _ in range(-s): + start = u*start.diff(u) + return expand_mul(start).subs(u, z) + return polylog(s, z) + + def _eval_is_zero(self): + z = self.args[1] + if z.is_zero: + return True + + def _eval_nseries(self, x, n, logx, cdir=0): + from sympy.series.order import Order + nu, z = self.args + + z0 = z.subs(x, 0) + if z0 is S.NaN: + z0 = z.limit(x, 0, dir='-' if re(cdir).is_negative else '+') + + if z0.is_zero: + # In case of powers less than 1, number of terms need to be computed + # separately to avoid repeated callings of _eval_nseries with wrong n + try: + _, exp = z.leadterm(x) + except (ValueError, NotImplementedError): + return self + + if exp.is_positive: + newn = ceiling(n/exp) + o = Order(x**n, x) + r = z._eval_nseries(x, n, logx, cdir).removeO() + if r is S.Zero: + return o + + term = r + s = [term] + for k in range(2, newn): + term *= r + s.append(term/k**nu) + return Add(*s) + o + + return super(polylog, self)._eval_nseries(x, n, logx, cdir) + +############################################################################### +###################### HURWITZ GENERALIZED ZETA FUNCTION ###################### +############################################################################### + + +class zeta(DefinedFunction): + r""" + Hurwitz zeta function (or Riemann zeta function). + + Explanation + =========== + + For $\operatorname{Re}(a) > 0$ and $\operatorname{Re}(s) > 1$, this + function is defined as + + .. math:: \zeta(s, a) = \sum_{n=0}^\infty \frac{1}{(n + a)^s}, + + where the standard choice of argument for $n + a$ is used. For fixed + $a$ not a nonpositive integer the Hurwitz zeta function admits a + meromorphic continuation to all of $\mathbb{C}$; it is an unbranched + function with a simple pole at $s = 1$. + + The Hurwitz zeta function is a special case of the Lerch transcendent: + + .. math:: \zeta(s, a) = \Phi(1, s, a). + + This formula defines an analytic continuation for all possible values of + $s$ and $a$ (also $\operatorname{Re}(a) < 0$), see the documentation of + :class:`lerchphi` for a description of the branching behavior. + + If no value is passed for $a$ a default value of $a = 1$ is assumed, + yielding the Riemann zeta function. + + Examples + ======== + + For $a = 1$ the Hurwitz zeta function reduces to the famous Riemann + zeta function: + + .. math:: \zeta(s, 1) = \zeta(s) = \sum_{n=1}^\infty \frac{1}{n^s}. + + >>> from sympy import zeta + >>> from sympy.abc import s + >>> zeta(s, 1) + zeta(s) + >>> zeta(s) + zeta(s) + + The Riemann zeta function can also be expressed using the Dirichlet eta + function: + + >>> from sympy import dirichlet_eta + >>> zeta(s).rewrite(dirichlet_eta) + dirichlet_eta(s)/(1 - 2**(1 - s)) + + The Riemann zeta function at nonnegative even and negative integer + values is related to the Bernoulli numbers and polynomials: + + >>> zeta(2) + pi**2/6 + >>> zeta(4) + pi**4/90 + >>> zeta(0) + -1/2 + >>> zeta(-1) + -1/12 + >>> zeta(-4) + 0 + + The specific formulae are: + + .. math:: \zeta(2n) = -\frac{(2\pi i)^{2n} B_{2n}}{2(2n)!} + .. math:: \zeta(-n,a) = -\frac{B_{n+1}(a)}{n+1} + + No closed-form expressions are known at positive odd integers, but + numerical evaluation is possible: + + >>> zeta(3).n() + 1.20205690315959 + + The derivative of $\zeta(s, a)$ with respect to $a$ can be computed: + + >>> from sympy.abc import a + >>> zeta(s, a).diff(a) + -s*zeta(s + 1, a) + + However the derivative with respect to $s$ has no useful closed form + expression: + + >>> zeta(s, a).diff(s) + Derivative(zeta(s, a), s) + + The Hurwitz zeta function can be expressed in terms of the Lerch + transcendent, :class:`~.lerchphi`: + + >>> from sympy import lerchphi + >>> zeta(s, a).rewrite(lerchphi) + lerchphi(1, s, a) + + See Also + ======== + + dirichlet_eta, lerchphi, polylog + + References + ========== + + .. [1] https://dlmf.nist.gov/25.11 + .. [2] https://en.wikipedia.org/wiki/Hurwitz_zeta_function + + """ + + @classmethod + def eval(cls, s, a=None): + if a is S.One: + return cls(s) + elif s is S.NaN or a is S.NaN: + return S.NaN + elif s is S.One: + return S.ComplexInfinity + elif s is S.Infinity: + return S.One + elif a is S.Infinity: + return S.Zero + + sint = s.is_Integer + if a is None: + a = S.One + if sint and s.is_nonpositive: + return bernoulli(1-s, a) / (s-1) + elif a is S.One: + if sint and s.is_even: + return -(2*pi*I)**s * bernoulli(s) / (2*factorial(s)) + elif sint and a.is_Integer and a.is_positive: + return cls(s) - harmonic(a-1, s) + elif a.is_Integer and a.is_nonpositive and \ + (s.is_integer is False or s.is_nonpositive is False): + return S.NaN + + def _eval_rewrite_as_bernoulli(self, s, a=1, **kwargs): + if a == 1 and s.is_integer and s.is_nonnegative and s.is_even: + return -(2*pi*I)**s * bernoulli(s) / (2*factorial(s)) + return bernoulli(1-s, a) / (s-1) + + def _eval_rewrite_as_dirichlet_eta(self, s, a=1, **kwargs): + if a != 1: + return self + s = self.args[0] + return dirichlet_eta(s)/(1 - 2**(1 - s)) + + def _eval_rewrite_as_lerchphi(self, s, a=1, **kwargs): + return lerchphi(1, s, a) + + def _eval_is_finite(self): + return fuzzy_not((self.args[0] - 1).is_zero) + + def _eval_expand_func(self, **hints): + s = self.args[0] + a = self.args[1] if len(self.args) > 1 else S.One + if a.is_integer: + if a.is_positive: + return zeta(s) - harmonic(a-1, s) + if a.is_nonpositive and (s.is_integer is False or + s.is_nonpositive is False): + return S.NaN + return self + + def fdiff(self, argindex=1): + if len(self.args) == 2: + s, a = self.args + else: + s, a = self.args + (1,) + if argindex == 2: + return -s*zeta(s + 1, a) + else: + raise ArgumentIndexError + + def _eval_as_leading_term(self, x, logx, cdir): + if len(self.args) == 2: + s, a = self.args + else: + s, a = self.args + (S.One,) + + try: + c, e = a.leadterm(x) + except NotImplementedError: + return self + + if e.is_negative and not s.is_positive: + raise NotImplementedError + + return super(zeta, self)._eval_as_leading_term(x, logx=logx, cdir=cdir) + + +class dirichlet_eta(DefinedFunction): + r""" + Dirichlet eta function. + + Explanation + =========== + + For $\operatorname{Re}(s) > 0$ and $0 < x \le 1$, this function is defined as + + .. math:: \eta(s, a) = \sum_{n=0}^\infty \frac{(-1)^n}{(n+a)^s}. + + It admits a unique analytic continuation to all of $\mathbb{C}$ for any + fixed $a$ not a nonpositive integer. It is an entire, unbranched function. + + It can be expressed using the Hurwitz zeta function as + + .. math:: \eta(s, a) = \zeta(s,a) - 2^{1-s} \zeta\left(s, \frac{a+1}{2}\right) + + and using the generalized Genocchi function as + + .. math:: \eta(s, a) = \frac{G(1-s, a)}{2(s-1)}. + + In both cases the limiting value of $\log2 - \psi(a) + \psi\left(\frac{a+1}{2}\right)$ + is used when $s = 1$. + + Examples + ======== + + >>> from sympy import dirichlet_eta, zeta + >>> from sympy.abc import s + >>> dirichlet_eta(s).rewrite(zeta) + Piecewise((log(2), Eq(s, 1)), ((1 - 2**(1 - s))*zeta(s), True)) + + See Also + ======== + + zeta + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Dirichlet_eta_function + .. [2] Peter Luschny, "An introduction to the Bernoulli function", + https://arxiv.org/abs/2009.06743 + + """ + + @classmethod + def eval(cls, s, a=None): + if a is S.One: + return cls(s) + if a is None: + if s == 1: + return log(2) + z = zeta(s) + if not z.has(zeta): + return (1 - 2**(1-s)) * z + return + elif s == 1: + from sympy.functions.special.gamma_functions import digamma + return log(2) - digamma(a) + digamma((a+1)/2) + z1 = zeta(s, a) + z2 = zeta(s, (a+1)/2) + if not z1.has(zeta) and not z2.has(zeta): + return z1 - 2**(1-s) * z2 + + def _eval_rewrite_as_zeta(self, s, a=1, **kwargs): + from sympy.functions.special.gamma_functions import digamma + if a == 1: + return Piecewise((log(2), Eq(s, 1)), ((1 - 2**(1-s)) * zeta(s), True)) + return Piecewise((log(2) - digamma(a) + digamma((a+1)/2), Eq(s, 1)), + (zeta(s, a) - 2**(1-s) * zeta(s, (a+1)/2), True)) + + def _eval_rewrite_as_genocchi(self, s, a=S.One, **kwargs): + from sympy.functions.special.gamma_functions import digamma + return Piecewise((log(2) - digamma(a) + digamma((a+1)/2), Eq(s, 1)), + (genocchi(1-s, a) / (2 * (s-1)), True)) + + def _eval_evalf(self, prec): + if all(i.is_number for i in self.args): + return self.rewrite(zeta)._eval_evalf(prec) + + +class riemann_xi(DefinedFunction): + r""" + Riemann Xi function. + + Examples + ======== + + The Riemann Xi function is closely related to the Riemann zeta function. + The zeros of Riemann Xi function are precisely the non-trivial zeros + of the zeta function. + + >>> from sympy import riemann_xi, zeta + >>> from sympy.abc import s + >>> riemann_xi(s).rewrite(zeta) + s*(s - 1)*gamma(s/2)*zeta(s)/(2*pi**(s/2)) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Riemann_Xi_function + + """ + + + @classmethod + def eval(cls, s): + from sympy.functions.special.gamma_functions import gamma + z = zeta(s) + if s in (S.Zero, S.One): + return S.Half + + if not isinstance(z, zeta): + return s*(s - 1)*gamma(s/2)*z/(2*pi**(s/2)) + + def _eval_rewrite_as_zeta(self, s, **kwargs): + from sympy.functions.special.gamma_functions import gamma + return s*(s - 1)*gamma(s/2)*zeta(s)/(2*pi**(s/2)) + + +class stieltjes(DefinedFunction): + r""" + Represents Stieltjes constants, $\gamma_{k}$ that occur in + Laurent Series expansion of the Riemann zeta function. + + Examples + ======== + + >>> from sympy import stieltjes + >>> from sympy.abc import n, m + >>> stieltjes(n) + stieltjes(n) + + The zero'th stieltjes constant: + + >>> stieltjes(0) + EulerGamma + >>> stieltjes(0, 1) + EulerGamma + + For generalized stieltjes constants: + + >>> stieltjes(n, m) + stieltjes(n, m) + + Constants are only defined for integers >= 0: + + >>> stieltjes(-1) + zoo + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Stieltjes_constants + + """ + + @classmethod + def eval(cls, n, a=None): + if a is not None: + a = sympify(a) + if a is S.NaN: + return S.NaN + if a.is_Integer and a.is_nonpositive: + return S.ComplexInfinity + + if n.is_Number: + if n is S.NaN: + return S.NaN + elif n < 0: + return S.ComplexInfinity + elif not n.is_Integer: + return S.ComplexInfinity + elif n is S.Zero and a in [None, 1]: + return S.EulerGamma + + if n.is_extended_negative: + return S.ComplexInfinity + + if n.is_zero and a in [None, 1]: + return S.EulerGamma + + if n.is_integer == False: + return S.ComplexInfinity + + +@cacheit +def _dilogtable(): + return { + S.Half: pi**2/12 - log(2)**2/2, + Integer(2) : pi**2/4 - I*pi*log(2), + -(sqrt(5) - 1)/2 : -pi**2/15 + log((sqrt(5)-1)/2)**2/2, + -(sqrt(5) + 1)/2 : -pi**2/10 - log((sqrt(5)+1)/2)**2, + (3 - sqrt(5))/2 : pi**2/15 - log((sqrt(5)-1)/2)**2, + (sqrt(5) - 1)/2 : pi**2/10 - log((sqrt(5)-1)/2)**2, + I : I*S.Catalan - pi**2/48, + -I : -I*S.Catalan - pi**2/48, + 1 - I : pi**2/16 - I*S.Catalan - pi*I/4*log(2), + 1 + I : pi**2/16 + I*S.Catalan + pi*I/4*log(2), + (1 - I)/2 : -log(2)**2/8 + pi*I*log(2)/8 + 5*pi**2/96 - I*S.Catalan + } diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..bb85d4ff5d53eb44a039a95cfc2fff687322cc76 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/__init__.py @@ -0,0 +1,45 @@ +""" +A geometry module for the SymPy library. This module contains all of the +entities and functions needed to construct basic geometrical data and to +perform simple informational queries. + +Usage: +====== + +Examples +======== + +""" +from sympy.geometry.point import Point, Point2D, Point3D +from sympy.geometry.line import Line, Ray, Segment, Line2D, Segment2D, Ray2D, \ + Line3D, Segment3D, Ray3D +from sympy.geometry.plane import Plane +from sympy.geometry.ellipse import Ellipse, Circle +from sympy.geometry.polygon import Polygon, RegularPolygon, Triangle, rad, deg +from sympy.geometry.util import are_similar, centroid, convex_hull, idiff, \ + intersection, closest_points, farthest_points +from sympy.geometry.exceptions import GeometryError +from sympy.geometry.curve import Curve +from sympy.geometry.parabola import Parabola + +__all__ = [ + 'Point', 'Point2D', 'Point3D', + + 'Line', 'Ray', 'Segment', 'Line2D', 'Segment2D', 'Ray2D', 'Line3D', + 'Segment3D', 'Ray3D', + + 'Plane', + + 'Ellipse', 'Circle', + + 'Polygon', 'RegularPolygon', 'Triangle', 'rad', 'deg', + + 'are_similar', 'centroid', 'convex_hull', 'idiff', 'intersection', + 'closest_points', 'farthest_points', + + 'GeometryError', + + 'Curve', + + 'Parabola', +] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/curve.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/curve.py new file mode 100644 index 0000000000000000000000000000000000000000..c074f22cad79b1261ad44be4ccface972cdd3b82 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/curve.py @@ -0,0 +1,424 @@ +"""Curves in 2-dimensional Euclidean space. + +Contains +======== +Curve + +""" + +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.core import diff +from sympy.core.containers import Tuple +from sympy.core.symbol import _symbol +from sympy.geometry.entity import GeometryEntity, GeometrySet +from sympy.geometry.point import Point +from sympy.integrals import integrate +from sympy.matrices import Matrix, rot_axis3 +from sympy.utilities.iterables import is_sequence + +from mpmath.libmp.libmpf import prec_to_dps + + +class Curve(GeometrySet): + """A curve in space. + + A curve is defined by parametric functions for the coordinates, a + parameter and the lower and upper bounds for the parameter value. + + Parameters + ========== + + function : list of functions + limits : 3-tuple + Function parameter and lower and upper bounds. + + Attributes + ========== + + functions + parameter + limits + + Raises + ====== + + ValueError + When `functions` are specified incorrectly. + When `limits` are specified incorrectly. + + Examples + ======== + + >>> from sympy import Curve, sin, cos, interpolate + >>> from sympy.abc import t, a + >>> C = Curve((sin(t), cos(t)), (t, 0, 2)) + >>> C.functions + (sin(t), cos(t)) + >>> C.limits + (t, 0, 2) + >>> C.parameter + t + >>> C = Curve((t, interpolate([1, 4, 9, 16], t)), (t, 0, 1)); C + Curve((t, t**2), (t, 0, 1)) + >>> C.subs(t, 4) + Point2D(4, 16) + >>> C.arbitrary_point(a) + Point2D(a, a**2) + + See Also + ======== + + sympy.core.function.Function + sympy.polys.polyfuncs.interpolate + + """ + + def __new__(cls, function, limits): + if not is_sequence(function) or len(function) != 2: + raise ValueError("Function argument should be (x(t), y(t)) " + "but got %s" % str(function)) + if not is_sequence(limits) or len(limits) != 3: + raise ValueError("Limit argument should be (t, tmin, tmax) " + "but got %s" % str(limits)) + + return GeometryEntity.__new__(cls, Tuple(*function), Tuple(*limits)) + + def __call__(self, f): + return self.subs(self.parameter, f) + + def _eval_subs(self, old, new): + if old == self.parameter: + return Point(*[f.subs(old, new) for f in self.functions]) + + def _eval_evalf(self, prec=15, **options): + f, (t, a, b) = self.args + dps = prec_to_dps(prec) + f = tuple([i.evalf(n=dps, **options) for i in f]) + a, b = [i.evalf(n=dps, **options) for i in (a, b)] + return self.func(f, (t, a, b)) + + def arbitrary_point(self, parameter='t'): + """A parameterized point on the curve. + + Parameters + ========== + + parameter : str or Symbol, optional + Default value is 't'. + The Curve's parameter is selected with None or self.parameter + otherwise the provided symbol is used. + + Returns + ======= + + Point : + Returns a point in parametric form. + + Raises + ====== + + ValueError + When `parameter` already appears in the functions. + + Examples + ======== + + >>> from sympy import Curve, Symbol + >>> from sympy.abc import s + >>> C = Curve([2*s, s**2], (s, 0, 2)) + >>> C.arbitrary_point() + Point2D(2*t, t**2) + >>> C.arbitrary_point(C.parameter) + Point2D(2*s, s**2) + >>> C.arbitrary_point(None) + Point2D(2*s, s**2) + >>> C.arbitrary_point(Symbol('a')) + Point2D(2*a, a**2) + + See Also + ======== + + sympy.geometry.point.Point + + """ + if parameter is None: + return Point(*self.functions) + + tnew = _symbol(parameter, self.parameter, real=True) + t = self.parameter + if (tnew.name != t.name and + tnew.name in (f.name for f in self.free_symbols)): + raise ValueError('Symbol %s already appears in object ' + 'and cannot be used as a parameter.' % tnew.name) + return Point(*[w.subs(t, tnew) for w in self.functions]) + + @property + def free_symbols(self): + """Return a set of symbols other than the bound symbols used to + parametrically define the Curve. + + Returns + ======= + + set : + Set of all non-parameterized symbols. + + Examples + ======== + + >>> from sympy.abc import t, a + >>> from sympy import Curve + >>> Curve((t, t**2), (t, 0, 2)).free_symbols + set() + >>> Curve((t, t**2), (t, a, 2)).free_symbols + {a} + + """ + free = set() + for a in self.functions + self.limits[1:]: + free |= a.free_symbols + free = free.difference({self.parameter}) + return free + + @property + def ambient_dimension(self): + """The dimension of the curve. + + Returns + ======= + + int : + the dimension of curve. + + Examples + ======== + + >>> from sympy.abc import t + >>> from sympy import Curve + >>> C = Curve((t, t**2), (t, 0, 2)) + >>> C.ambient_dimension + 2 + + """ + + return len(self.args[0]) + + @property + def functions(self): + """The functions specifying the curve. + + Returns + ======= + + functions : + list of parameterized coordinate functions. + + Examples + ======== + + >>> from sympy.abc import t + >>> from sympy import Curve + >>> C = Curve((t, t**2), (t, 0, 2)) + >>> C.functions + (t, t**2) + + See Also + ======== + + parameter + + """ + return self.args[0] + + @property + def limits(self): + """The limits for the curve. + + Returns + ======= + + limits : tuple + Contains parameter and lower and upper limits. + + Examples + ======== + + >>> from sympy.abc import t + >>> from sympy import Curve + >>> C = Curve([t, t**3], (t, -2, 2)) + >>> C.limits + (t, -2, 2) + + See Also + ======== + + plot_interval + + """ + return self.args[1] + + @property + def parameter(self): + """The curve function variable. + + Returns + ======= + + Symbol : + returns a bound symbol. + + Examples + ======== + + >>> from sympy.abc import t + >>> from sympy import Curve + >>> C = Curve([t, t**2], (t, 0, 2)) + >>> C.parameter + t + + See Also + ======== + + functions + + """ + return self.args[1][0] + + @property + def length(self): + """The curve length. + + Examples + ======== + + >>> from sympy import Curve + >>> from sympy.abc import t + >>> Curve((t, t), (t, 0, 1)).length + sqrt(2) + + """ + integrand = sqrt(sum(diff(func, self.limits[0])**2 for func in self.functions)) + return integrate(integrand, self.limits) + + def plot_interval(self, parameter='t'): + """The plot interval for the default geometric plot of the curve. + + Parameters + ========== + + parameter : str or Symbol, optional + Default value is 't'; + otherwise the provided symbol is used. + + Returns + ======= + + List : + the plot interval as below: + [parameter, lower_bound, upper_bound] + + Examples + ======== + + >>> from sympy import Curve, sin + >>> from sympy.abc import x, s + >>> Curve((x, sin(x)), (x, 1, 2)).plot_interval() + [t, 1, 2] + >>> Curve((x, sin(x)), (x, 1, 2)).plot_interval(s) + [s, 1, 2] + + See Also + ======== + + limits : Returns limits of the parameter interval + + """ + t = _symbol(parameter, self.parameter, real=True) + return [t] + list(self.limits[1:]) + + def rotate(self, angle=0, pt=None): + """This function is used to rotate a curve along given point ``pt`` at given angle(in radian). + + Parameters + ========== + + angle : + the angle at which the curve will be rotated(in radian) in counterclockwise direction. + default value of angle is 0. + + pt : Point + the point along which the curve will be rotated. + If no point given, the curve will be rotated around origin. + + Returns + ======= + + Curve : + returns a curve rotated at given angle along given point. + + Examples + ======== + + >>> from sympy import Curve, pi + >>> from sympy.abc import x + >>> Curve((x, x), (x, 0, 1)).rotate(pi/2) + Curve((-x, x), (x, 0, 1)) + + """ + if pt: + pt = -Point(pt, dim=2) + else: + pt = Point(0,0) + rv = self.translate(*pt.args) + f = list(rv.functions) + f.append(0) + f = Matrix(1, 3, f) + f *= rot_axis3(angle) + rv = self.func(f[0, :2].tolist()[0], self.limits) + pt = -pt + return rv.translate(*pt.args) + + def scale(self, x=1, y=1, pt=None): + """Override GeometryEntity.scale since Curve is not made up of Points. + + Returns + ======= + + Curve : + returns scaled curve. + + Examples + ======== + + >>> from sympy import Curve + >>> from sympy.abc import x + >>> Curve((x, x), (x, 0, 1)).scale(2) + Curve((2*x, x), (x, 0, 1)) + + """ + if pt: + pt = Point(pt, dim=2) + return self.translate(*(-pt).args).scale(x, y).translate(*pt.args) + fx, fy = self.functions + return self.func((fx*x, fy*y), self.limits) + + def translate(self, x=0, y=0): + """Translate the Curve by (x, y). + + Returns + ======= + + Curve : + returns a translated curve. + + Examples + ======== + + >>> from sympy import Curve + >>> from sympy.abc import x + >>> Curve((x, x), (x, 0, 1)).translate(1, 2) + Curve((x + 1, x + 2), (x, 0, 1)) + + """ + fx, fy = self.functions + return self.func((fx + x, fy + y), self.limits) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/ellipse.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/ellipse.py new file mode 100644 index 0000000000000000000000000000000000000000..199db25fde9b019893a275d69959154990e8a4a7 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/ellipse.py @@ -0,0 +1,1768 @@ +"""Elliptical geometrical entities. + +Contains +* Ellipse +* Circle + +""" + +from sympy.core.expr import Expr +from sympy.core.relational import Eq +from sympy.core import S, pi, sympify +from sympy.core.evalf import N +from sympy.core.parameters import global_parameters +from sympy.core.logic import fuzzy_bool +from sympy.core.numbers import Rational, oo +from sympy.core.sorting import ordered +from sympy.core.symbol import Dummy, uniquely_named_symbol, _symbol +from sympy.simplify.simplify import simplify +from sympy.simplify.trigsimp import trigsimp +from sympy.functions.elementary.miscellaneous import sqrt, Max +from sympy.functions.elementary.trigonometric import cos, sin +from sympy.functions.special.elliptic_integrals import elliptic_e +from .entity import GeometryEntity, GeometrySet +from .exceptions import GeometryError +from .line import Line, Segment, Ray2D, Segment2D, Line2D, LinearEntity3D +from .point import Point, Point2D, Point3D +from .util import idiff, find +from sympy.polys import DomainError, Poly, PolynomialError +from sympy.polys.polyutils import _not_a_coeff, _nsort +from sympy.solvers import solve +from sympy.solvers.solveset import linear_coeffs +from sympy.utilities.misc import filldedent, func_name + +from mpmath.libmp.libmpf import prec_to_dps + +import random + +x, y = [Dummy('ellipse_dummy', real=True) for i in range(2)] + + +class Ellipse(GeometrySet): + """An elliptical GeometryEntity. + + Parameters + ========== + + center : Point, optional + Default value is Point(0, 0) + hradius : number or SymPy expression, optional + vradius : number or SymPy expression, optional + eccentricity : number or SymPy expression, optional + Two of `hradius`, `vradius` and `eccentricity` must be supplied to + create an Ellipse. The third is derived from the two supplied. + + Attributes + ========== + + center + hradius + vradius + area + circumference + eccentricity + periapsis + apoapsis + focus_distance + foci + + Raises + ====== + + GeometryError + When `hradius`, `vradius` and `eccentricity` are incorrectly supplied + as parameters. + TypeError + When `center` is not a Point. + + See Also + ======== + + Circle + + Notes + ----- + Constructed from a center and two radii, the first being the horizontal + radius (along the x-axis) and the second being the vertical radius (along + the y-axis). + + When symbolic value for hradius and vradius are used, any calculation that + refers to the foci or the major or minor axis will assume that the ellipse + has its major radius on the x-axis. If this is not true then a manual + rotation is necessary. + + Examples + ======== + + >>> from sympy import Ellipse, Point, Rational + >>> e1 = Ellipse(Point(0, 0), 5, 1) + >>> e1.hradius, e1.vradius + (5, 1) + >>> e2 = Ellipse(Point(3, 1), hradius=3, eccentricity=Rational(4, 5)) + >>> e2 + Ellipse(Point2D(3, 1), 3, 9/5) + + """ + + def __contains__(self, o): + if isinstance(o, Point): + res = self.equation(x, y).subs({x: o.x, y: o.y}) + return trigsimp(simplify(res)) is S.Zero + elif isinstance(o, Ellipse): + return self == o + return False + + def __eq__(self, o): + """Is the other GeometryEntity the same as this ellipse?""" + return isinstance(o, Ellipse) and (self.center == o.center and + self.hradius == o.hradius and + self.vradius == o.vradius) + + def __hash__(self): + return super().__hash__() + + def __new__( + cls, center=None, hradius=None, vradius=None, eccentricity=None, **kwargs): + + hradius = sympify(hradius) + vradius = sympify(vradius) + + if center is None: + center = Point(0, 0) + else: + if len(center) != 2: + raise ValueError('The center of "{}" must be a two dimensional point'.format(cls)) + center = Point(center, dim=2) + + if len(list(filter(lambda x: x is not None, (hradius, vradius, eccentricity)))) != 2: + raise ValueError(filldedent(''' + Exactly two arguments of "hradius", "vradius", and + "eccentricity" must not be None.''')) + + if eccentricity is not None: + eccentricity = sympify(eccentricity) + if eccentricity.is_negative: + raise GeometryError("Eccentricity of ellipse/circle should lie between [0, 1)") + elif hradius is None: + hradius = vradius / sqrt(1 - eccentricity**2) + elif vradius is None: + vradius = hradius * sqrt(1 - eccentricity**2) + + if hradius == vradius: + return Circle(center, hradius, **kwargs) + + if S.Zero in (hradius, vradius): + return Segment(Point(center[0] - hradius, center[1] - vradius), Point(center[0] + hradius, center[1] + vradius)) + + if hradius.is_real is False or vradius.is_real is False: + raise GeometryError("Invalid value encountered when computing hradius / vradius.") + + return GeometryEntity.__new__(cls, center, hradius, vradius, **kwargs) + + def _svg(self, scale_factor=1., fill_color="#66cc99"): + """Returns SVG ellipse element for the Ellipse. + + Parameters + ========== + + scale_factor : float + Multiplication factor for the SVG stroke-width. Default is 1. + fill_color : str, optional + Hex string for fill color. Default is "#66cc99". + """ + + c = N(self.center) + h, v = N(self.hradius), N(self.vradius) + return ( + '' + ).format(2. * scale_factor, fill_color, c.x, c.y, h, v) + + @property + def ambient_dimension(self): + return 2 + + @property + def apoapsis(self): + """The apoapsis of the ellipse. + + The greatest distance between the focus and the contour. + + Returns + ======= + + apoapsis : number + + See Also + ======== + + periapsis : Returns shortest distance between foci and contour + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.apoapsis + 2*sqrt(2) + 3 + + """ + return self.major * (1 + self.eccentricity) + + def arbitrary_point(self, parameter='t'): + """A parameterized point on the ellipse. + + Parameters + ========== + + parameter : str, optional + Default value is 't'. + + Returns + ======= + + arbitrary_point : Point + + Raises + ====== + + ValueError + When `parameter` already appears in the functions. + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> e1 = Ellipse(Point(0, 0), 3, 2) + >>> e1.arbitrary_point() + Point2D(3*cos(t), 2*sin(t)) + + """ + t = _symbol(parameter, real=True) + if t.name in (f.name for f in self.free_symbols): + raise ValueError(filldedent('Symbol %s already appears in object ' + 'and cannot be used as a parameter.' % t.name)) + return Point(self.center.x + self.hradius*cos(t), + self.center.y + self.vradius*sin(t)) + + @property + def area(self): + """The area of the ellipse. + + Returns + ======= + + area : number + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.area + 3*pi + + """ + return simplify(S.Pi * self.hradius * self.vradius) + + @property + def bounds(self): + """Return a tuple (xmin, ymin, xmax, ymax) representing the bounding + rectangle for the geometric figure. + + """ + + h, v = self.hradius, self.vradius + return (self.center.x - h, self.center.y - v, self.center.x + h, self.center.y + v) + + @property + def center(self): + """The center of the ellipse. + + Returns + ======= + + center : number + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.center + Point2D(0, 0) + + """ + return self.args[0] + + @property + def circumference(self): + """The circumference of the ellipse. + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.circumference + 12*elliptic_e(8/9) + + """ + if self.eccentricity == 1: + # degenerate + return 4*self.major + elif self.eccentricity == 0: + # circle + return 2*pi*self.hradius + else: + return 4*self.major*elliptic_e(self.eccentricity**2) + + @property + def eccentricity(self): + """The eccentricity of the ellipse. + + Returns + ======= + + eccentricity : number + + Examples + ======== + + >>> from sympy import Point, Ellipse, sqrt + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, sqrt(2)) + >>> e1.eccentricity + sqrt(7)/3 + + """ + return self.focus_distance / self.major + + def encloses_point(self, p): + """ + Return True if p is enclosed by (is inside of) self. + + Notes + ----- + Being on the border of self is considered False. + + Parameters + ========== + + p : Point + + Returns + ======= + + encloses_point : True, False or None + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Ellipse, S + >>> from sympy.abc import t + >>> e = Ellipse((0, 0), 3, 2) + >>> e.encloses_point((0, 0)) + True + >>> e.encloses_point(e.arbitrary_point(t).subs(t, S.Half)) + False + >>> e.encloses_point((4, 0)) + False + + """ + p = Point(p, dim=2) + if p in self: + return False + + if len(self.foci) == 2: + # if the combined distance from the foci to p (h1 + h2) is less + # than the combined distance from the foci to the minor axis + # (which is the same as the major axis length) then p is inside + # the ellipse + h1, h2 = [f.distance(p) for f in self.foci] + test = 2*self.major - (h1 + h2) + else: + test = self.radius - self.center.distance(p) + + return fuzzy_bool(test.is_positive) + + def equation(self, x='x', y='y', _slope=None): + """ + Returns the equation of an ellipse aligned with the x and y axes; + when slope is given, the equation returned corresponds to an ellipse + with a major axis having that slope. + + Parameters + ========== + + x : str, optional + Label for the x-axis. Default value is 'x'. + y : str, optional + Label for the y-axis. Default value is 'y'. + _slope : Expr, optional + The slope of the major axis. Ignored when 'None'. + + Returns + ======= + + equation : SymPy expression + + See Also + ======== + + arbitrary_point : Returns parameterized point on ellipse + + Examples + ======== + + >>> from sympy import Point, Ellipse, pi + >>> from sympy.abc import x, y + >>> e1 = Ellipse(Point(1, 0), 3, 2) + >>> eq1 = e1.equation(x, y); eq1 + y**2/4 + (x/3 - 1/3)**2 - 1 + >>> eq2 = e1.equation(x, y, _slope=1); eq2 + (-x + y + 1)**2/8 + (x + y - 1)**2/18 - 1 + + A point on e1 satisfies eq1. Let's use one on the x-axis: + + >>> p1 = e1.center + Point(e1.major, 0) + >>> assert eq1.subs(x, p1.x).subs(y, p1.y) == 0 + + When rotated the same as the rotated ellipse, about the center + point of the ellipse, it will satisfy the rotated ellipse's + equation, too: + + >>> r1 = p1.rotate(pi/4, e1.center) + >>> assert eq2.subs(x, r1.x).subs(y, r1.y) == 0 + + References + ========== + + .. [1] https://math.stackexchange.com/questions/108270/what-is-the-equation-of-an-ellipse-that-is-not-aligned-with-the-axis + .. [2] https://en.wikipedia.org/wiki/Ellipse#Shifted_ellipse + + """ + + x = _symbol(x, real=True) + y = _symbol(y, real=True) + + dx = x - self.center.x + dy = y - self.center.y + + if _slope is not None: + L = (dy - _slope*dx)**2 + l = (_slope*dy + dx)**2 + h = 1 + _slope**2 + b = h*self.major**2 + a = h*self.minor**2 + return l/b + L/a - 1 + + else: + t1 = (dx/self.hradius)**2 + t2 = (dy/self.vradius)**2 + return t1 + t2 - 1 + + def evolute(self, x='x', y='y'): + """The equation of evolute of the ellipse. + + Parameters + ========== + + x : str, optional + Label for the x-axis. Default value is 'x'. + y : str, optional + Label for the y-axis. Default value is 'y'. + + Returns + ======= + + equation : SymPy expression + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> e1 = Ellipse(Point(1, 0), 3, 2) + >>> e1.evolute() + 2**(2/3)*y**(2/3) + (3*x - 3)**(2/3) - 5**(2/3) + """ + if len(self.args) != 3: + raise NotImplementedError('Evolute of arbitrary Ellipse is not supported.') + x = _symbol(x, real=True) + y = _symbol(y, real=True) + t1 = (self.hradius*(x - self.center.x))**Rational(2, 3) + t2 = (self.vradius*(y - self.center.y))**Rational(2, 3) + return t1 + t2 - (self.hradius**2 - self.vradius**2)**Rational(2, 3) + + @property + def foci(self): + """The foci of the ellipse. + + Notes + ----- + The foci can only be calculated if the major/minor axes are known. + + Raises + ====== + + ValueError + When the major and minor axis cannot be determined. + + See Also + ======== + + sympy.geometry.point.Point + focus_distance : Returns the distance between focus and center + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.foci + (Point2D(-2*sqrt(2), 0), Point2D(2*sqrt(2), 0)) + + """ + c = self.center + hr, vr = self.hradius, self.vradius + if hr == vr: + return (c, c) + + # calculate focus distance manually, since focus_distance calls this + # routine + fd = sqrt(self.major**2 - self.minor**2) + if hr == self.minor: + # foci on the y-axis + return (c + Point(0, -fd), c + Point(0, fd)) + elif hr == self.major: + # foci on the x-axis + return (c + Point(-fd, 0), c + Point(fd, 0)) + + @property + def focus_distance(self): + """The focal distance of the ellipse. + + The distance between the center and one focus. + + Returns + ======= + + focus_distance : number + + See Also + ======== + + foci + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.focus_distance + 2*sqrt(2) + + """ + return Point.distance(self.center, self.foci[0]) + + @property + def hradius(self): + """The horizontal radius of the ellipse. + + Returns + ======= + + hradius : number + + See Also + ======== + + vradius, major, minor + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.hradius + 3 + + """ + return self.args[1] + + def intersection(self, o): + """The intersection of this ellipse and another geometrical entity + `o`. + + Parameters + ========== + + o : GeometryEntity + + Returns + ======= + + intersection : list of GeometryEntity objects + + Notes + ----- + Currently supports intersections with Point, Line, Segment, Ray, + Circle and Ellipse types. + + See Also + ======== + + sympy.geometry.entity.GeometryEntity + + Examples + ======== + + >>> from sympy import Ellipse, Point, Line + >>> e = Ellipse(Point(0, 0), 5, 7) + >>> e.intersection(Point(0, 0)) + [] + >>> e.intersection(Point(5, 0)) + [Point2D(5, 0)] + >>> e.intersection(Line(Point(0,0), Point(0, 1))) + [Point2D(0, -7), Point2D(0, 7)] + >>> e.intersection(Line(Point(5,0), Point(5, 1))) + [Point2D(5, 0)] + >>> e.intersection(Line(Point(6,0), Point(6, 1))) + [] + >>> e = Ellipse(Point(-1, 0), 4, 3) + >>> e.intersection(Ellipse(Point(1, 0), 4, 3)) + [Point2D(0, -3*sqrt(15)/4), Point2D(0, 3*sqrt(15)/4)] + >>> e.intersection(Ellipse(Point(5, 0), 4, 3)) + [Point2D(2, -3*sqrt(7)/4), Point2D(2, 3*sqrt(7)/4)] + >>> e.intersection(Ellipse(Point(100500, 0), 4, 3)) + [] + >>> e.intersection(Ellipse(Point(0, 0), 3, 4)) + [Point2D(3, 0), Point2D(-363/175, -48*sqrt(111)/175), Point2D(-363/175, 48*sqrt(111)/175)] + >>> e.intersection(Ellipse(Point(-1, 0), 3, 4)) + [Point2D(-17/5, -12/5), Point2D(-17/5, 12/5), Point2D(7/5, -12/5), Point2D(7/5, 12/5)] + """ + # TODO: Replace solve with nonlinsolve, when nonlinsolve will be able to solve in real domain + + if isinstance(o, Point): + if o in self: + return [o] + else: + return [] + + elif isinstance(o, (Segment2D, Ray2D)): + ellipse_equation = self.equation(x, y) + result = solve([ellipse_equation, Line( + o.points[0], o.points[1]).equation(x, y)], [x, y], + set=True)[1] + return list(ordered([Point(i) for i in result if i in o])) + + elif isinstance(o, Polygon): + return o.intersection(self) + + elif isinstance(o, (Ellipse, Line2D)): + if o == self: + return self + else: + ellipse_equation = self.equation(x, y) + return list(ordered([Point(i) for i in solve( + [ellipse_equation, o.equation(x, y)], [x, y], + set=True)[1]])) + elif isinstance(o, LinearEntity3D): + raise TypeError('Entity must be two dimensional, not three dimensional') + else: + raise TypeError('Intersection not handled for %s' % func_name(o)) + + def is_tangent(self, o): + """Is `o` tangent to the ellipse? + + Parameters + ========== + + o : GeometryEntity + An Ellipse, LinearEntity or Polygon + + Raises + ====== + + NotImplementedError + When the wrong type of argument is supplied. + + Returns + ======= + + is_tangent: boolean + True if o is tangent to the ellipse, False otherwise. + + See Also + ======== + + tangent_lines + + Examples + ======== + + >>> from sympy import Point, Ellipse, Line + >>> p0, p1, p2 = Point(0, 0), Point(3, 0), Point(3, 3) + >>> e1 = Ellipse(p0, 3, 2) + >>> l1 = Line(p1, p2) + >>> e1.is_tangent(l1) + True + + """ + if isinstance(o, Point2D): + return False + elif isinstance(o, Ellipse): + intersect = self.intersection(o) + if isinstance(intersect, Ellipse): + return True + elif intersect: + return all((self.tangent_lines(i)[0]).equals(o.tangent_lines(i)[0]) for i in intersect) + else: + return False + elif isinstance(o, Line2D): + hit = self.intersection(o) + if not hit: + return False + if len(hit) == 1: + return True + # might return None if it can't decide + return hit[0].equals(hit[1]) + elif isinstance(o, (Segment2D, Ray2D)): + intersect = self.intersection(o) + if len(intersect) == 1: + return o in self.tangent_lines(intersect[0])[0] + else: + return False + elif isinstance(o, Polygon): + return all(self.is_tangent(s) for s in o.sides) + elif isinstance(o, (LinearEntity3D, Point3D)): + raise TypeError('Entity must be two dimensional, not three dimensional') + else: + raise TypeError('Is_tangent not handled for %s' % func_name(o)) + + @property + def major(self): + """Longer axis of the ellipse (if it can be determined) else hradius. + + Returns + ======= + + major : number or expression + + See Also + ======== + + hradius, vradius, minor + + Examples + ======== + + >>> from sympy import Point, Ellipse, Symbol + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.major + 3 + + >>> a = Symbol('a') + >>> b = Symbol('b') + >>> Ellipse(p1, a, b).major + a + >>> Ellipse(p1, b, a).major + b + + >>> m = Symbol('m') + >>> M = m + 1 + >>> Ellipse(p1, m, M).major + m + 1 + + """ + ab = self.args[1:3] + if len(ab) == 1: + return ab[0] + a, b = ab + o = b - a < 0 + if o == True: + return a + elif o == False: + return b + return self.hradius + + @property + def minor(self): + """Shorter axis of the ellipse (if it can be determined) else vradius. + + Returns + ======= + + minor : number or expression + + See Also + ======== + + hradius, vradius, major + + Examples + ======== + + >>> from sympy import Point, Ellipse, Symbol + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.minor + 1 + + >>> a = Symbol('a') + >>> b = Symbol('b') + >>> Ellipse(p1, a, b).minor + b + >>> Ellipse(p1, b, a).minor + a + + >>> m = Symbol('m') + >>> M = m + 1 + >>> Ellipse(p1, m, M).minor + m + + """ + ab = self.args[1:3] + if len(ab) == 1: + return ab[0] + a, b = ab + o = a - b < 0 + if o == True: + return a + elif o == False: + return b + return self.vradius + + def normal_lines(self, p, prec=None): + """Normal lines between `p` and the ellipse. + + Parameters + ========== + + p : Point + + Returns + ======= + + normal_lines : list with 1, 2 or 4 Lines + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> e = Ellipse((0, 0), 2, 3) + >>> c = e.center + >>> e.normal_lines(c + Point(1, 0)) + [Line2D(Point2D(0, 0), Point2D(1, 0))] + >>> e.normal_lines(c) + [Line2D(Point2D(0, 0), Point2D(0, 1)), Line2D(Point2D(0, 0), Point2D(1, 0))] + + Off-axis points require the solution of a quartic equation. This + often leads to very large expressions that may be of little practical + use. An approximate solution of `prec` digits can be obtained by + passing in the desired value: + + >>> e.normal_lines((3, 3), prec=2) + [Line2D(Point2D(-0.81, -2.7), Point2D(0.19, -1.2)), + Line2D(Point2D(1.5, -2.0), Point2D(2.5, -2.7))] + + Whereas the above solution has an operation count of 12, the exact + solution has an operation count of 2020. + """ + p = Point(p, dim=2) + + # XXX change True to something like self.angle == 0 if the arbitrarily + # rotated ellipse is introduced. + # https://github.com/sympy/sympy/issues/2815) + if True: + rv = [] + if p.x == self.center.x: + rv.append(Line(self.center, slope=oo)) + if p.y == self.center.y: + rv.append(Line(self.center, slope=0)) + if rv: + # at these special orientations of p either 1 or 2 normals + # exist and we are done + return rv + + # find the 4 normal points and construct lines through them with + # the corresponding slope + eq = self.equation(x, y) + dydx = idiff(eq, y, x) + norm = -1/dydx + slope = Line(p, (x, y)).slope + seq = slope - norm + + # TODO: Replace solve with solveset, when this line is tested + yis = solve(seq, y)[0] + xeq = eq.subs(y, yis).as_numer_denom()[0].expand() + if len(xeq.free_symbols) == 1: + try: + # this is so much faster, it's worth a try + xsol = Poly(xeq, x).real_roots() + except (DomainError, PolynomialError, NotImplementedError): + # TODO: Replace solve with solveset, when these lines are tested + xsol = _nsort(solve(xeq, x), separated=True)[0] + points = [Point(i, solve(eq.subs(x, i), y)[0]) for i in xsol] + else: + raise NotImplementedError( + 'intersections for the general ellipse are not supported') + slopes = [norm.subs(zip((x, y), pt.args)) for pt in points] + if prec is not None: + points = [pt.n(prec) for pt in points] + slopes = [i if _not_a_coeff(i) else i.n(prec) for i in slopes] + return [Line(pt, slope=s) for pt, s in zip(points, slopes)] + + @property + def periapsis(self): + """The periapsis of the ellipse. + + The shortest distance between the focus and the contour. + + Returns + ======= + + periapsis : number + + See Also + ======== + + apoapsis : Returns greatest distance between focus and contour + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.periapsis + 3 - 2*sqrt(2) + + """ + return self.major * (1 - self.eccentricity) + + @property + def semilatus_rectum(self): + """ + Calculates the semi-latus rectum of the Ellipse. + + Semi-latus rectum is defined as one half of the chord through a + focus parallel to the conic section directrix of a conic section. + + Returns + ======= + + semilatus_rectum : number + + See Also + ======== + + apoapsis : Returns greatest distance between focus and contour + + periapsis : The shortest distance between the focus and the contour + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.semilatus_rectum + 1/3 + + References + ========== + + .. [1] https://mathworld.wolfram.com/SemilatusRectum.html + .. [2] https://en.wikipedia.org/wiki/Ellipse#Semi-latus_rectum + + """ + return self.major * (1 - self.eccentricity ** 2) + + def auxiliary_circle(self): + """Returns a Circle whose diameter is the major axis of the ellipse. + + Examples + ======== + + >>> from sympy import Ellipse, Point, symbols + >>> c = Point(1, 2) + >>> Ellipse(c, 8, 7).auxiliary_circle() + Circle(Point2D(1, 2), 8) + >>> a, b = symbols('a b') + >>> Ellipse(c, a, b).auxiliary_circle() + Circle(Point2D(1, 2), Max(a, b)) + """ + return Circle(self.center, Max(self.hradius, self.vradius)) + + def director_circle(self): + """ + Returns a Circle consisting of all points where two perpendicular + tangent lines to the ellipse cross each other. + + Returns + ======= + + Circle + A director circle returned as a geometric object. + + Examples + ======== + + >>> from sympy import Ellipse, Point, symbols + >>> c = Point(3,8) + >>> Ellipse(c, 7, 9).director_circle() + Circle(Point2D(3, 8), sqrt(130)) + >>> a, b = symbols('a b') + >>> Ellipse(c, a, b).director_circle() + Circle(Point2D(3, 8), sqrt(a**2 + b**2)) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Director_circle + + """ + return Circle(self.center, sqrt(self.hradius**2 + self.vradius**2)) + + def plot_interval(self, parameter='t'): + """The plot interval for the default geometric plot of the Ellipse. + + Parameters + ========== + + parameter : str, optional + Default value is 't'. + + Returns + ======= + + plot_interval : list + [parameter, lower_bound, upper_bound] + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> e1 = Ellipse(Point(0, 0), 3, 2) + >>> e1.plot_interval() + [t, -pi, pi] + + """ + t = _symbol(parameter, real=True) + return [t, -S.Pi, S.Pi] + + def random_point(self, seed=None): + """A random point on the ellipse. + + Returns + ======= + + point : Point + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> e1 = Ellipse(Point(0, 0), 3, 2) + >>> e1.random_point() # gives some random point + Point2D(...) + >>> p1 = e1.random_point(seed=0); p1.n(2) + Point2D(2.1, 1.4) + + Notes + ===== + + When creating a random point, one may simply replace the + parameter with a random number. When doing so, however, the + random number should be made a Rational or else the point + may not test as being in the ellipse: + + >>> from sympy.abc import t + >>> from sympy import Rational + >>> arb = e1.arbitrary_point(t); arb + Point2D(3*cos(t), 2*sin(t)) + >>> arb.subs(t, .1) in e1 + False + >>> arb.subs(t, Rational(.1)) in e1 + True + >>> arb.subs(t, Rational('.1')) in e1 + True + + See Also + ======== + sympy.geometry.point.Point + arbitrary_point : Returns parameterized point on ellipse + """ + t = _symbol('t', real=True) + x, y = self.arbitrary_point(t).args + # get a random value in [-1, 1) corresponding to cos(t) + # and confirm that it will test as being in the ellipse + if seed is not None: + rng = random.Random(seed) + else: + rng = random + # simplify this now or else the Float will turn s into a Float + r = Rational(rng.random()) + c = 2*r - 1 + s = sqrt(1 - c**2) + return Point(x.subs(cos(t), c), y.subs(sin(t), s)) + + def reflect(self, line): + """Override GeometryEntity.reflect since the radius + is not a GeometryEntity. + + Examples + ======== + + >>> from sympy import Circle, Line + >>> Circle((0, 1), 1).reflect(Line((0, 0), (1, 1))) + Circle(Point2D(1, 0), -1) + >>> from sympy import Ellipse, Line, Point + >>> Ellipse(Point(3, 4), 1, 3).reflect(Line(Point(0, -4), Point(5, 0))) + Traceback (most recent call last): + ... + NotImplementedError: + General Ellipse is not supported but the equation of the reflected + Ellipse is given by the zeros of: f(x, y) = (9*x/41 + 40*y/41 + + 37/41)**2 + (40*x/123 - 3*y/41 - 364/123)**2 - 1 + + Notes + ===== + + Until the general ellipse (with no axis parallel to the x-axis) is + supported a NotImplemented error is raised and the equation whose + zeros define the rotated ellipse is given. + + """ + + if line.slope in (0, oo): + c = self.center + c = c.reflect(line) + return self.func(c, -self.hradius, self.vradius) + else: + x, y = [uniquely_named_symbol( + name, (self, line), modify=lambda s: '_' + s, real=True) + for name in 'xy'] + expr = self.equation(x, y) + p = Point(x, y).reflect(line) + result = expr.subs(zip((x, y), p.args + ), simultaneous=True) + raise NotImplementedError(filldedent( + 'General Ellipse is not supported but the equation ' + 'of the reflected Ellipse is given by the zeros of: ' + + "f(%s, %s) = %s" % (str(x), str(y), str(result)))) + + def rotate(self, angle=0, pt=None): + """Rotate ``angle`` radians counterclockwise about Point ``pt``. + + Note: since the general ellipse is not supported, only rotations that + are integer multiples of pi/2 are allowed. + + Examples + ======== + + >>> from sympy import Ellipse, pi + >>> Ellipse((1, 0), 2, 1).rotate(pi/2) + Ellipse(Point2D(0, 1), 1, 2) + >>> Ellipse((1, 0), 2, 1).rotate(pi) + Ellipse(Point2D(-1, 0), 2, 1) + """ + if self.hradius == self.vradius: + return self.func(self.center.rotate(angle, pt), self.hradius) + if (angle/S.Pi).is_integer: + return super().rotate(angle, pt) + if (2*angle/S.Pi).is_integer: + return self.func(self.center.rotate(angle, pt), self.vradius, self.hradius) + # XXX see https://github.com/sympy/sympy/issues/2815 for general ellipes + raise NotImplementedError('Only rotations of pi/2 are currently supported for Ellipse.') + + def scale(self, x=1, y=1, pt=None): + """Override GeometryEntity.scale since it is the major and minor + axes which must be scaled and they are not GeometryEntities. + + Examples + ======== + + >>> from sympy import Ellipse + >>> Ellipse((0, 0), 2, 1).scale(2, 4) + Circle(Point2D(0, 0), 4) + >>> Ellipse((0, 0), 2, 1).scale(2) + Ellipse(Point2D(0, 0), 4, 1) + """ + c = self.center + if pt: + pt = Point(pt, dim=2) + return self.translate(*(-pt).args).scale(x, y).translate(*pt.args) + h = self.hradius + v = self.vradius + return self.func(c.scale(x, y), hradius=h*x, vradius=v*y) + + def tangent_lines(self, p): + """Tangent lines between `p` and the ellipse. + + If `p` is on the ellipse, returns the tangent line through point `p`. + Otherwise, returns the tangent line(s) from `p` to the ellipse, or + None if no tangent line is possible (e.g., `p` inside ellipse). + + Parameters + ========== + + p : Point + + Returns + ======= + + tangent_lines : list with 1 or 2 Lines + + Raises + ====== + + NotImplementedError + Can only find tangent lines for a point, `p`, on the ellipse. + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.line.Line + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> e1 = Ellipse(Point(0, 0), 3, 2) + >>> e1.tangent_lines(Point(3, 0)) + [Line2D(Point2D(3, 0), Point2D(3, -12))] + + """ + p = Point(p, dim=2) + if self.encloses_point(p): + return [] + + if p in self: + delta = self.center - p + rise = (self.vradius**2)*delta.x + run = -(self.hradius**2)*delta.y + p2 = Point(simplify(p.x + run), + simplify(p.y + rise)) + return [Line(p, p2)] + else: + if len(self.foci) == 2: + f1, f2 = self.foci + maj = self.hradius + test = (2*maj - + Point.distance(f1, p) - + Point.distance(f2, p)) + else: + test = self.radius - Point.distance(self.center, p) + if test.is_number and test.is_positive: + return [] + # else p is outside the ellipse or we can't tell. In case of the + # latter, the solutions returned will only be valid if + # the point is not inside the ellipse; if it is, nan will result. + eq = self.equation(x, y) + dydx = idiff(eq, y, x) + slope = Line(p, Point(x, y)).slope + + # TODO: Replace solve with solveset, when this line is tested + tangent_points = solve([slope - dydx, eq], [x, y]) + + # handle horizontal and vertical tangent lines + if len(tangent_points) == 1: + if tangent_points[0][ + 0] == p.x or tangent_points[0][1] == p.y: + return [Line(p, p + Point(1, 0)), Line(p, p + Point(0, 1))] + else: + return [Line(p, p + Point(0, 1)), Line(p, tangent_points[0])] + + # others + return [Line(p, tangent_points[0]), Line(p, tangent_points[1])] + + @property + def vradius(self): + """The vertical radius of the ellipse. + + Returns + ======= + + vradius : number + + See Also + ======== + + hradius, major, minor + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.vradius + 1 + + """ + return self.args[2] + + + def second_moment_of_area(self, point=None): + """Returns the second moment and product moment area of an ellipse. + + Parameters + ========== + + point : Point, two-tuple of sympifiable objects, or None(default=None) + point is the point about which second moment of area is to be found. + If "point=None" it will be calculated about the axis passing through the + centroid of the ellipse. + + Returns + ======= + + I_xx, I_yy, I_xy : number or SymPy expression + I_xx, I_yy are second moment of area of an ellise. + I_xy is product moment of area of an ellipse. + + Examples + ======== + + >>> from sympy import Point, Ellipse + >>> p1 = Point(0, 0) + >>> e1 = Ellipse(p1, 3, 1) + >>> e1.second_moment_of_area() + (3*pi/4, 27*pi/4, 0) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/List_of_second_moments_of_area + + """ + + I_xx = (S.Pi*(self.hradius)*(self.vradius**3))/4 + I_yy = (S.Pi*(self.hradius**3)*(self.vradius))/4 + I_xy = 0 + + if point is None: + return I_xx, I_yy, I_xy + + # parallel axis theorem + I_xx = I_xx + self.area*((point[1] - self.center.y)**2) + I_yy = I_yy + self.area*((point[0] - self.center.x)**2) + I_xy = I_xy + self.area*(point[0] - self.center.x)*(point[1] - self.center.y) + + return I_xx, I_yy, I_xy + + + def polar_second_moment_of_area(self): + """Returns the polar second moment of area of an Ellipse + + It is a constituent of the second moment of area, linked through + the perpendicular axis theorem. While the planar second moment of + area describes an object's resistance to deflection (bending) when + subjected to a force applied to a plane parallel to the central + axis, the polar second moment of area describes an object's + resistance to deflection when subjected to a moment applied in a + plane perpendicular to the object's central axis (i.e. parallel to + the cross-section) + + Examples + ======== + + >>> from sympy import symbols, Circle, Ellipse + >>> c = Circle((5, 5), 4) + >>> c.polar_second_moment_of_area() + 128*pi + >>> a, b = symbols('a, b') + >>> e = Ellipse((0, 0), a, b) + >>> e.polar_second_moment_of_area() + pi*a**3*b/4 + pi*a*b**3/4 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Polar_moment_of_inertia + + """ + second_moment = self.second_moment_of_area() + return second_moment[0] + second_moment[1] + + + def section_modulus(self, point=None): + """Returns a tuple with the section modulus of an ellipse + + Section modulus is a geometric property of an ellipse defined as the + ratio of second moment of area to the distance of the extreme end of + the ellipse from the centroidal axis. + + Parameters + ========== + + point : Point, two-tuple of sympifyable objects, or None(default=None) + point is the point at which section modulus is to be found. + If "point=None" section modulus will be calculated for the + point farthest from the centroidal axis of the ellipse. + + Returns + ======= + + S_x, S_y: numbers or SymPy expressions + S_x is the section modulus with respect to the x-axis + S_y is the section modulus with respect to the y-axis + A negative sign indicates that the section modulus is + determined for a point below the centroidal axis. + + Examples + ======== + + >>> from sympy import Symbol, Ellipse, Circle, Point2D + >>> d = Symbol('d', positive=True) + >>> c = Circle((0, 0), d/2) + >>> c.section_modulus() + (pi*d**3/32, pi*d**3/32) + >>> e = Ellipse(Point2D(0, 0), 2, 4) + >>> e.section_modulus() + (8*pi, 4*pi) + >>> e.section_modulus((2, 2)) + (16*pi, 4*pi) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Section_modulus + + """ + x_c, y_c = self.center + if point is None: + # taking x and y as maximum distances from centroid + x_min, y_min, x_max, y_max = self.bounds + y = max(y_c - y_min, y_max - y_c) + x = max(x_c - x_min, x_max - x_c) + else: + # taking x and y as distances of the given point from the center + point = Point2D(point) + y = point.y - y_c + x = point.x - x_c + + second_moment = self.second_moment_of_area() + S_x = second_moment[0]/y + S_y = second_moment[1]/x + + return S_x, S_y + + +class Circle(Ellipse): + r"""A circle in space. + + Constructed simply from a center and a radius, from three + non-collinear points, or the equation of a circle. + + Parameters + ========== + + center : Point + radius : number or SymPy expression + points : sequence of three Points + equation : equation of a circle + + Attributes + ========== + + radius (synonymous with hradius, vradius, major and minor) + circumference + equation + + Raises + ====== + + GeometryError + When the given equation is not that of a circle. + When trying to construct circle from incorrect parameters. + + See Also + ======== + + Ellipse, sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Circle, Eq + >>> from sympy.abc import x, y, a, b + + A circle constructed from a center and radius: + + >>> c1 = Circle(Point(0, 0), 5) + >>> c1.hradius, c1.vradius, c1.radius + (5, 5, 5) + + A circle constructed from three points: + + >>> c2 = Circle(Point(0, 0), Point(1, 1), Point(1, 0)) + >>> c2.hradius, c2.vradius, c2.radius, c2.center + (sqrt(2)/2, sqrt(2)/2, sqrt(2)/2, Point2D(1/2, 1/2)) + + A circle can be constructed from an equation in the form + `ax^2 + by^2 + gx + hy + c = 0`, too: + + >>> Circle(x**2 + y**2 - 25) + Circle(Point2D(0, 0), 5) + + If the variables corresponding to x and y are named something + else, their name or symbol can be supplied: + + >>> Circle(Eq(a**2 + b**2, 25), x='a', y=b) + Circle(Point2D(0, 0), 5) + """ + + def __new__(cls, *args, **kwargs): + evaluate = kwargs.get('evaluate', global_parameters.evaluate) + if len(args) == 1 and isinstance(args[0], (Expr, Eq)): + x = kwargs.get('x', 'x') + y = kwargs.get('y', 'y') + equation = args[0].expand() + if isinstance(equation, Eq): + equation = equation.lhs - equation.rhs + x = find(x, equation) + y = find(y, equation) + + try: + a, b, c, d, e = linear_coeffs(equation, x**2, y**2, x, y) + except ValueError: + raise GeometryError("The given equation is not that of a circle.") + + if S.Zero in (a, b) or a != b: + raise GeometryError("The given equation is not that of a circle.") + + center_x = -c/a/2 + center_y = -d/b/2 + r2 = (center_x**2) + (center_y**2) - e/a + + return Circle((center_x, center_y), sqrt(r2), evaluate=evaluate) + + else: + c, r = None, None + if len(args) == 3: + args = [Point(a, dim=2, evaluate=evaluate) for a in args] + t = Triangle(*args) + if not isinstance(t, Triangle): + return t + c = t.circumcenter + r = t.circumradius + elif len(args) == 2: + # Assume (center, radius) pair + c = Point(args[0], dim=2, evaluate=evaluate) + r = args[1] + # this will prohibit imaginary radius + try: + r = Point(r, 0, evaluate=evaluate).x + except ValueError: + raise GeometryError("Circle with imaginary radius is not permitted") + + if not (c is None or r is None): + if r == 0: + return c + return GeometryEntity.__new__(cls, c, r, **kwargs) + + raise GeometryError("Circle.__new__ received unknown arguments") + + def _eval_evalf(self, prec=15, **options): + pt, r = self.args + dps = prec_to_dps(prec) + pt = pt.evalf(n=dps, **options) + r = r.evalf(n=dps, **options) + return self.func(pt, r, evaluate=False) + + @property + def circumference(self): + """The circumference of the circle. + + Returns + ======= + + circumference : number or SymPy expression + + Examples + ======== + + >>> from sympy import Point, Circle + >>> c1 = Circle(Point(3, 4), 6) + >>> c1.circumference + 12*pi + + """ + return 2 * S.Pi * self.radius + + def equation(self, x='x', y='y'): + """The equation of the circle. + + Parameters + ========== + + x : str or Symbol, optional + Default value is 'x'. + y : str or Symbol, optional + Default value is 'y'. + + Returns + ======= + + equation : SymPy expression + + Examples + ======== + + >>> from sympy import Point, Circle + >>> c1 = Circle(Point(0, 0), 5) + >>> c1.equation() + x**2 + y**2 - 25 + + """ + x = _symbol(x, real=True) + y = _symbol(y, real=True) + t1 = (x - self.center.x)**2 + t2 = (y - self.center.y)**2 + return t1 + t2 - self.major**2 + + def intersection(self, o): + """The intersection of this circle with another geometrical entity. + + Parameters + ========== + + o : GeometryEntity + + Returns + ======= + + intersection : list of GeometryEntities + + Examples + ======== + + >>> from sympy import Point, Circle, Line, Ray + >>> p1, p2, p3 = Point(0, 0), Point(5, 5), Point(6, 0) + >>> p4 = Point(5, 0) + >>> c1 = Circle(p1, 5) + >>> c1.intersection(p2) + [] + >>> c1.intersection(p4) + [Point2D(5, 0)] + >>> c1.intersection(Ray(p1, p2)) + [Point2D(5*sqrt(2)/2, 5*sqrt(2)/2)] + >>> c1.intersection(Line(p2, p3)) + [] + + """ + return Ellipse.intersection(self, o) + + @property + def radius(self): + """The radius of the circle. + + Returns + ======= + + radius : number or SymPy expression + + See Also + ======== + + Ellipse.major, Ellipse.minor, Ellipse.hradius, Ellipse.vradius + + Examples + ======== + + >>> from sympy import Point, Circle + >>> c1 = Circle(Point(3, 4), 6) + >>> c1.radius + 6 + + """ + return self.args[1] + + def reflect(self, line): + """Override GeometryEntity.reflect since the radius + is not a GeometryEntity. + + Examples + ======== + + >>> from sympy import Circle, Line + >>> Circle((0, 1), 1).reflect(Line((0, 0), (1, 1))) + Circle(Point2D(1, 0), -1) + """ + c = self.center + c = c.reflect(line) + return self.func(c, -self.radius) + + def scale(self, x=1, y=1, pt=None): + """Override GeometryEntity.scale since the radius + is not a GeometryEntity. + + Examples + ======== + + >>> from sympy import Circle + >>> Circle((0, 0), 1).scale(2, 2) + Circle(Point2D(0, 0), 2) + >>> Circle((0, 0), 1).scale(2, 4) + Ellipse(Point2D(0, 0), 2, 4) + """ + c = self.center + if pt: + pt = Point(pt, dim=2) + return self.translate(*(-pt).args).scale(x, y).translate(*pt.args) + c = c.scale(x, y) + x, y = [abs(i) for i in (x, y)] + if x == y: + return self.func(c, x*self.radius) + h = v = self.radius + return Ellipse(c, hradius=h*x, vradius=v*y) + + @property + def vradius(self): + """ + This Ellipse property is an alias for the Circle's radius. + + Whereas hradius, major and minor can use Ellipse's conventions, + the vradius does not exist for a circle. It is always a positive + value in order that the Circle, like Polygons, will have an + area that can be positive or negative as determined by the sign + of the hradius. + + Examples + ======== + + >>> from sympy import Point, Circle + >>> c1 = Circle(Point(3, 4), 6) + >>> c1.vradius + 6 + """ + return abs(self.radius) + + +from .polygon import Polygon, Triangle diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/entity.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/entity.py new file mode 100644 index 0000000000000000000000000000000000000000..5ea1e807542c43eb955c2d778cec0f101d78bdce --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/entity.py @@ -0,0 +1,641 @@ +"""The definition of the base geometrical entity with attributes common to +all derived geometrical entities. + +Contains +======== + +GeometryEntity +GeometricSet + +Notes +===== + +A GeometryEntity is any object that has special geometric properties. +A GeometrySet is a superclass of any GeometryEntity that can also +be viewed as a sympy.sets.Set. In particular, points are the only +GeometryEntity not considered a Set. + +Rn is a GeometrySet representing n-dimensional Euclidean space. R2 and +R3 are currently the only ambient spaces implemented. + +""" +from __future__ import annotations + +from sympy.core.basic import Basic +from sympy.core.containers import Tuple +from sympy.core.evalf import EvalfMixin, N +from sympy.core.numbers import oo +from sympy.core.symbol import Dummy +from sympy.core.sympify import sympify +from sympy.functions.elementary.trigonometric import cos, sin, atan +from sympy.matrices import eye +from sympy.multipledispatch import dispatch +from sympy.printing import sstr +from sympy.sets import Set, Union, FiniteSet +from sympy.sets.handlers.intersection import intersection_sets +from sympy.sets.handlers.union import union_sets +from sympy.solvers.solvers import solve +from sympy.utilities.misc import func_name +from sympy.utilities.iterables import is_sequence + + +# How entities are ordered; used by __cmp__ in GeometryEntity +ordering_of_classes = [ + "Point2D", + "Point3D", + "Point", + "Segment2D", + "Ray2D", + "Line2D", + "Segment3D", + "Line3D", + "Ray3D", + "Segment", + "Ray", + "Line", + "Plane", + "Triangle", + "RegularPolygon", + "Polygon", + "Circle", + "Ellipse", + "Curve", + "Parabola" +] + + +x, y = [Dummy('entity_dummy') for i in range(2)] +T = Dummy('entity_dummy', real=True) + + +class GeometryEntity(Basic, EvalfMixin): + """The base class for all geometrical entities. + + This class does not represent any particular geometric entity, it only + provides the implementation of some methods common to all subclasses. + + """ + + __slots__: tuple[str, ...] = () + + def __cmp__(self, other): + """Comparison of two GeometryEntities.""" + n1 = self.__class__.__name__ + n2 = other.__class__.__name__ + c = (n1 > n2) - (n1 < n2) + if not c: + return 0 + + i1 = -1 + for cls in self.__class__.__mro__: + try: + i1 = ordering_of_classes.index(cls.__name__) + break + except ValueError: + i1 = -1 + if i1 == -1: + return c + + i2 = -1 + for cls in other.__class__.__mro__: + try: + i2 = ordering_of_classes.index(cls.__name__) + break + except ValueError: + i2 = -1 + if i2 == -1: + return c + + return (i1 > i2) - (i1 < i2) + + def __contains__(self, other): + """Subclasses should implement this method for anything more complex than equality.""" + if type(self) is type(other): + return self == other + raise NotImplementedError() + + def __getnewargs__(self): + """Returns a tuple that will be passed to __new__ on unpickling.""" + return tuple(self.args) + + def __ne__(self, o): + """Test inequality of two geometrical entities.""" + return not self == o + + def __new__(cls, *args, **kwargs): + # Points are sequences, but they should not + # be converted to Tuples, so use this detection function instead. + def is_seq_and_not_point(a): + # we cannot use isinstance(a, Point) since we cannot import Point + if hasattr(a, 'is_Point') and a.is_Point: + return False + return is_sequence(a) + + args = [Tuple(*a) if is_seq_and_not_point(a) else sympify(a) for a in args] + return Basic.__new__(cls, *args) + + def __radd__(self, a): + """Implementation of reverse add method.""" + return a.__add__(self) + + def __rtruediv__(self, a): + """Implementation of reverse division method.""" + return a.__truediv__(self) + + def __repr__(self): + """String representation of a GeometryEntity that can be evaluated + by sympy.""" + return type(self).__name__ + repr(self.args) + + def __rmul__(self, a): + """Implementation of reverse multiplication method.""" + return a.__mul__(self) + + def __rsub__(self, a): + """Implementation of reverse subtraction method.""" + return a.__sub__(self) + + def __str__(self): + """String representation of a GeometryEntity.""" + return type(self).__name__ + sstr(self.args) + + def _eval_subs(self, old, new): + from sympy.geometry.point import Point, Point3D + if is_sequence(old) or is_sequence(new): + if isinstance(self, Point3D): + old = Point3D(old) + new = Point3D(new) + else: + old = Point(old) + new = Point(new) + return self._subs(old, new) + + def _repr_svg_(self): + """SVG representation of a GeometryEntity suitable for IPython""" + + try: + bounds = self.bounds + except (NotImplementedError, TypeError): + # if we have no SVG representation, return None so IPython + # will fall back to the next representation + return None + + if not all(x.is_number and x.is_finite for x in bounds): + return None + + svg_top = ''' + + + + + + + + + + + ''' + + # Establish SVG canvas that will fit all the data + small space + xmin, ymin, xmax, ymax = map(N, bounds) + if xmin == xmax and ymin == ymax: + # This is a point; buffer using an arbitrary size + xmin, ymin, xmax, ymax = xmin - .5, ymin -.5, xmax + .5, ymax + .5 + else: + # Expand bounds by a fraction of the data ranges + expand = 0.1 # or 10%; this keeps arrowheads in view (R plots use 4%) + widest_part = max([xmax - xmin, ymax - ymin]) + expand_amount = widest_part * expand + xmin -= expand_amount + ymin -= expand_amount + xmax += expand_amount + ymax += expand_amount + dx = xmax - xmin + dy = ymax - ymin + width = min([max([100., dx]), 300]) + height = min([max([100., dy]), 300]) + + scale_factor = 1. if max(width, height) == 0 else max(dx, dy) / max(width, height) + try: + svg = self._svg(scale_factor) + except (NotImplementedError, TypeError): + # if we have no SVG representation, return None so IPython + # will fall back to the next representation + return None + + view_box = "{} {} {} {}".format(xmin, ymin, dx, dy) + transform = "matrix(1,0,0,-1,0,{})".format(ymax + ymin) + svg_top = svg_top.format(view_box, width, height) + + return svg_top + ( + '{}' + ).format(transform, svg) + + def _svg(self, scale_factor=1., fill_color="#66cc99"): + """Returns SVG path element for the GeometryEntity. + + Parameters + ========== + + scale_factor : float + Multiplication factor for the SVG stroke-width. Default is 1. + fill_color : str, optional + Hex string for fill color. Default is "#66cc99". + """ + raise NotImplementedError() + + def _sympy_(self): + return self + + @property + def ambient_dimension(self): + """What is the dimension of the space that the object is contained in?""" + raise NotImplementedError() + + @property + def bounds(self): + """Return a tuple (xmin, ymin, xmax, ymax) representing the bounding + rectangle for the geometric figure. + + """ + + raise NotImplementedError() + + def encloses(self, o): + """ + Return True if o is inside (not on or outside) the boundaries of self. + + The object will be decomposed into Points and individual Entities need + only define an encloses_point method for their class. + + See Also + ======== + + sympy.geometry.ellipse.Ellipse.encloses_point + sympy.geometry.polygon.Polygon.encloses_point + + Examples + ======== + + >>> from sympy import RegularPolygon, Point, Polygon + >>> t = Polygon(*RegularPolygon(Point(0, 0), 1, 3).vertices) + >>> t2 = Polygon(*RegularPolygon(Point(0, 0), 2, 3).vertices) + >>> t2.encloses(t) + True + >>> t.encloses(t2) + False + + """ + + from sympy.geometry.point import Point + from sympy.geometry.line import Segment, Ray, Line + from sympy.geometry.ellipse import Ellipse + from sympy.geometry.polygon import Polygon, RegularPolygon + + if isinstance(o, Point): + return self.encloses_point(o) + elif isinstance(o, Segment): + return all(self.encloses_point(x) for x in o.points) + elif isinstance(o, (Ray, Line)): + return False + elif isinstance(o, Ellipse): + return self.encloses_point(o.center) and \ + self.encloses_point( + Point(o.center.x + o.hradius, o.center.y)) and \ + not self.intersection(o) + elif isinstance(o, Polygon): + if isinstance(o, RegularPolygon): + if not self.encloses_point(o.center): + return False + return all(self.encloses_point(v) for v in o.vertices) + raise NotImplementedError() + + def equals(self, o): + return self == o + + def intersection(self, o): + """ + Returns a list of all of the intersections of self with o. + + Notes + ===== + + An entity is not required to implement this method. + + If two different types of entities can intersect, the item with + higher index in ordering_of_classes should implement + intersections with anything having a lower index. + + See Also + ======== + + sympy.geometry.util.intersection + + """ + raise NotImplementedError() + + def is_similar(self, other): + """Is this geometrical entity similar to another geometrical entity? + + Two entities are similar if a uniform scaling (enlarging or + shrinking) of one of the entities will allow one to obtain the other. + + Notes + ===== + + This method is not intended to be used directly but rather + through the `are_similar` function found in util.py. + An entity is not required to implement this method. + If two different types of entities can be similar, it is only + required that one of them be able to determine this. + + See Also + ======== + + scale + + """ + raise NotImplementedError() + + def reflect(self, line): + """ + Reflects an object across a line. + + Parameters + ========== + + line: Line + + Examples + ======== + + >>> from sympy import pi, sqrt, Line, RegularPolygon + >>> l = Line((0, pi), slope=sqrt(2)) + >>> pent = RegularPolygon((1, 2), 1, 5) + >>> rpent = pent.reflect(l) + >>> rpent + RegularPolygon(Point2D(-2*sqrt(2)*pi/3 - 1/3 + 4*sqrt(2)/3, 2/3 + 2*sqrt(2)/3 + 2*pi/3), -1, 5, -atan(2*sqrt(2)) + 3*pi/5) + + >>> from sympy import pi, Line, Circle, Point + >>> l = Line((0, pi), slope=1) + >>> circ = Circle(Point(0, 0), 5) + >>> rcirc = circ.reflect(l) + >>> rcirc + Circle(Point2D(-pi, pi), -5) + + """ + from sympy.geometry.point import Point + + g = self + l = line + o = Point(0, 0) + if l.slope.is_zero: + v = l.args[0].y + if not v: # x-axis + return g.scale(y=-1) + reps = [(p, p.translate(y=2*(v - p.y))) for p in g.atoms(Point)] + elif l.slope is oo: + v = l.args[0].x + if not v: # y-axis + return g.scale(x=-1) + reps = [(p, p.translate(x=2*(v - p.x))) for p in g.atoms(Point)] + else: + if not hasattr(g, 'reflect') and not all( + isinstance(arg, Point) for arg in g.args): + raise NotImplementedError( + 'reflect undefined or non-Point args in %s' % g) + a = atan(l.slope) + c = l.coefficients + d = -c[-1]/c[1] # y-intercept + # apply the transform to a single point + xf = Point(x, y) + xf = xf.translate(y=-d).rotate(-a, o).scale(y=-1 + ).rotate(a, o).translate(y=d) + # replace every point using that transform + reps = [(p, xf.xreplace({x: p.x, y: p.y})) for p in g.atoms(Point)] + return g.xreplace(dict(reps)) + + def rotate(self, angle, pt=None): + """Rotate ``angle`` radians counterclockwise about Point ``pt``. + + The default pt is the origin, Point(0, 0) + + See Also + ======== + + scale, translate + + Examples + ======== + + >>> from sympy import Point, RegularPolygon, Polygon, pi + >>> t = Polygon(*RegularPolygon(Point(0, 0), 1, 3).vertices) + >>> t # vertex on x axis + Triangle(Point2D(1, 0), Point2D(-1/2, sqrt(3)/2), Point2D(-1/2, -sqrt(3)/2)) + >>> t.rotate(pi/2) # vertex on y axis now + Triangle(Point2D(0, 1), Point2D(-sqrt(3)/2, -1/2), Point2D(sqrt(3)/2, -1/2)) + + """ + newargs = [] + for a in self.args: + if isinstance(a, GeometryEntity): + newargs.append(a.rotate(angle, pt)) + else: + newargs.append(a) + return type(self)(*newargs) + + def scale(self, x=1, y=1, pt=None): + """Scale the object by multiplying the x,y-coordinates by x and y. + + If pt is given, the scaling is done relative to that point; the + object is shifted by -pt, scaled, and shifted by pt. + + See Also + ======== + + rotate, translate + + Examples + ======== + + >>> from sympy import RegularPolygon, Point, Polygon + >>> t = Polygon(*RegularPolygon(Point(0, 0), 1, 3).vertices) + >>> t + Triangle(Point2D(1, 0), Point2D(-1/2, sqrt(3)/2), Point2D(-1/2, -sqrt(3)/2)) + >>> t.scale(2) + Triangle(Point2D(2, 0), Point2D(-1, sqrt(3)/2), Point2D(-1, -sqrt(3)/2)) + >>> t.scale(2, 2) + Triangle(Point2D(2, 0), Point2D(-1, sqrt(3)), Point2D(-1, -sqrt(3))) + + """ + from sympy.geometry.point import Point + if pt: + pt = Point(pt, dim=2) + return self.translate(*(-pt).args).scale(x, y).translate(*pt.args) + return type(self)(*[a.scale(x, y) for a in self.args]) # if this fails, override this class + + def translate(self, x=0, y=0): + """Shift the object by adding to the x,y-coordinates the values x and y. + + See Also + ======== + + rotate, scale + + Examples + ======== + + >>> from sympy import RegularPolygon, Point, Polygon + >>> t = Polygon(*RegularPolygon(Point(0, 0), 1, 3).vertices) + >>> t + Triangle(Point2D(1, 0), Point2D(-1/2, sqrt(3)/2), Point2D(-1/2, -sqrt(3)/2)) + >>> t.translate(2) + Triangle(Point2D(3, 0), Point2D(3/2, sqrt(3)/2), Point2D(3/2, -sqrt(3)/2)) + >>> t.translate(2, 2) + Triangle(Point2D(3, 2), Point2D(3/2, sqrt(3)/2 + 2), Point2D(3/2, 2 - sqrt(3)/2)) + + """ + newargs = [] + for a in self.args: + if isinstance(a, GeometryEntity): + newargs.append(a.translate(x, y)) + else: + newargs.append(a) + return self.func(*newargs) + + def parameter_value(self, other, t): + """Return the parameter corresponding to the given point. + Evaluating an arbitrary point of the entity at this parameter + value will return the given point. + + Examples + ======== + + >>> from sympy import Line, Point + >>> from sympy.abc import t + >>> a = Point(0, 0) + >>> b = Point(2, 2) + >>> Line(a, b).parameter_value((1, 1), t) + {t: 1/2} + >>> Line(a, b).arbitrary_point(t).subs(_) + Point2D(1, 1) + """ + from sympy.geometry.point import Point + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if not isinstance(other, Point): + raise ValueError("other must be a point") + sol = solve(self.arbitrary_point(T) - other, T, dict=True) + if not sol: + raise ValueError("Given point is not on %s" % func_name(self)) + return {t: sol[0][T]} + + +class GeometrySet(GeometryEntity, Set): + """Parent class of all GeometryEntity that are also Sets + (compatible with sympy.sets) + """ + __slots__ = () + + def _contains(self, other): + """sympy.sets uses the _contains method, so include it for compatibility.""" + + if isinstance(other, Set) and other.is_FiniteSet: + return all(self.__contains__(i) for i in other) + + return self.__contains__(other) + +@dispatch(GeometrySet, Set) # type:ignore # noqa:F811 +def union_sets(self, o): # noqa:F811 + """ Returns the union of self and o + for use with sympy.sets.Set, if possible. """ + + + # if its a FiniteSet, merge any points + # we contain and return a union with the rest + if o.is_FiniteSet: + other_points = [p for p in o if not self._contains(p)] + if len(other_points) == len(o): + return None + return Union(self, FiniteSet(*other_points)) + if self._contains(o): + return self + return None + + +@dispatch(GeometrySet, Set) # type: ignore # noqa:F811 +def intersection_sets(self, o): # noqa:F811 + """ Returns a sympy.sets.Set of intersection objects, + if possible. """ + + from sympy.geometry.point import Point + + try: + # if o is a FiniteSet, find the intersection directly + # to avoid infinite recursion + if o.is_FiniteSet: + inter = FiniteSet(*(p for p in o if self.contains(p))) + else: + inter = self.intersection(o) + except NotImplementedError: + # sympy.sets.Set.reduce expects None if an object + # doesn't know how to simplify + return None + + # put the points in a FiniteSet + points = FiniteSet(*[p for p in inter if isinstance(p, Point)]) + non_points = [p for p in inter if not isinstance(p, Point)] + + return Union(*(non_points + [points])) + +def translate(x, y): + """Return the matrix to translate a 2-D point by x and y.""" + rv = eye(3) + rv[2, 0] = x + rv[2, 1] = y + return rv + + +def scale(x, y, pt=None): + """Return the matrix to multiply a 2-D point's coordinates by x and y. + + If pt is given, the scaling is done relative to that point.""" + rv = eye(3) + rv[0, 0] = x + rv[1, 1] = y + if pt: + from sympy.geometry.point import Point + pt = Point(pt, dim=2) + tr1 = translate(*(-pt).args) + tr2 = translate(*pt.args) + return tr1*rv*tr2 + return rv + + +def rotate(th): + """Return the matrix to rotate a 2-D point about the origin by ``angle``. + + The angle is measured in radians. To Point a point about a point other + then the origin, translate the Point, do the rotation, and + translate it back: + + >>> from sympy.geometry.entity import rotate, translate + >>> from sympy import Point, pi + >>> rot_about_11 = translate(-1, -1)*rotate(pi/2)*translate(1, 1) + >>> Point(1, 1).transform(rot_about_11) + Point2D(1, 1) + >>> Point(0, 0).transform(rot_about_11) + Point2D(2, 0) + """ + s = sin(th) + rv = eye(3)*cos(th) + rv[0, 1] = s + rv[1, 0] = -s + rv[2, 2] = 1 + return rv diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/exceptions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/exceptions.py new file mode 100644 index 0000000000000000000000000000000000000000..41d97af718de2cebad3accefcd60e43ccf74a3f6 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/exceptions.py @@ -0,0 +1,5 @@ +"""Geometry Errors.""" + +class GeometryError(ValueError): + """An exception raised by classes in the geometry module.""" + pass diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/line.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/line.py new file mode 100644 index 0000000000000000000000000000000000000000..ed73d43d0c9581f9d51f299cf4425acb11958e57 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/line.py @@ -0,0 +1,2877 @@ +"""Line-like geometrical entities. + +Contains +======== +LinearEntity +Line +Ray +Segment +LinearEntity2D +Line2D +Ray2D +Segment2D +LinearEntity3D +Line3D +Ray3D +Segment3D + +""" + +from sympy.core.containers import Tuple +from sympy.core.evalf import N +from sympy.core.expr import Expr +from sympy.core.numbers import Rational, oo, Float +from sympy.core.relational import Eq +from sympy.core.singleton import S +from sympy.core.sorting import ordered +from sympy.core.symbol import _symbol, Dummy, uniquely_named_symbol +from sympy.core.sympify import sympify +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import (_pi_coeff, acos, tan, atan2) +from .entity import GeometryEntity, GeometrySet +from .exceptions import GeometryError +from .point import Point, Point3D +from .util import find, intersection +from sympy.logic.boolalg import And +from sympy.matrices import Matrix +from sympy.sets.sets import Intersection +from sympy.simplify.simplify import simplify +from sympy.solvers.solvers import solve +from sympy.solvers.solveset import linear_coeffs +from sympy.utilities.misc import Undecidable, filldedent + + +import random + + +t, u = [Dummy('line_dummy') for i in range(2)] + + +class LinearEntity(GeometrySet): + """A base class for all linear entities (Line, Ray and Segment) + in n-dimensional Euclidean space. + + Attributes + ========== + + ambient_dimension + direction + length + p1 + p2 + points + + Notes + ===== + + This is an abstract class and is not meant to be instantiated. + + See Also + ======== + + sympy.geometry.entity.GeometryEntity + + """ + def __new__(cls, p1, p2=None, **kwargs): + p1, p2 = Point._normalize_dimension(p1, p2) + if p1 == p2: + # sometimes we return a single point if we are not given two unique + # points. This is done in the specific subclass + raise ValueError( + "%s.__new__ requires two unique Points." % cls.__name__) + if len(p1) != len(p2): + raise ValueError( + "%s.__new__ requires two Points of equal dimension." % cls.__name__) + + return GeometryEntity.__new__(cls, p1, p2, **kwargs) + + def __contains__(self, other): + """Return a definitive answer or else raise an error if it cannot + be determined that other is on the boundaries of self.""" + result = self.contains(other) + + if result is not None: + return result + else: + raise Undecidable( + "Cannot decide whether '%s' contains '%s'" % (self, other)) + + def _span_test(self, other): + """Test whether the point `other` lies in the positive span of `self`. + A point x is 'in front' of a point y if x.dot(y) >= 0. Return + -1 if `other` is behind `self.p1`, 0 if `other` is `self.p1` and + and 1 if `other` is in front of `self.p1`.""" + if self.p1 == other: + return 0 + + rel_pos = other - self.p1 + d = self.direction + if d.dot(rel_pos) > 0: + return 1 + return -1 + + @property + def ambient_dimension(self): + """A property method that returns the dimension of LinearEntity + object. + + Parameters + ========== + + p1 : LinearEntity + + Returns + ======= + + dimension : integer + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(1, 1) + >>> l1 = Line(p1, p2) + >>> l1.ambient_dimension + 2 + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0, 0), Point(1, 1, 1) + >>> l1 = Line(p1, p2) + >>> l1.ambient_dimension + 3 + + """ + return len(self.p1) + + def angle_between(l1, l2): + """Return the non-reflex angle formed by rays emanating from + the origin with directions the same as the direction vectors + of the linear entities. + + Parameters + ========== + + l1 : LinearEntity + l2 : LinearEntity + + Returns + ======= + + angle : angle in radians + + Notes + ===== + + From the dot product of vectors v1 and v2 it is known that: + + ``dot(v1, v2) = |v1|*|v2|*cos(A)`` + + where A is the angle formed between the two vectors. We can + get the directional vectors of the two lines and readily + find the angle between the two using the above formula. + + See Also + ======== + + is_perpendicular, Ray2D.closing_angle + + Examples + ======== + + >>> from sympy import Line + >>> e = Line((0, 0), (1, 0)) + >>> ne = Line((0, 0), (1, 1)) + >>> sw = Line((1, 1), (0, 0)) + >>> ne.angle_between(e) + pi/4 + >>> sw.angle_between(e) + 3*pi/4 + + To obtain the non-obtuse angle at the intersection of lines, use + the ``smallest_angle_between`` method: + + >>> sw.smallest_angle_between(e) + pi/4 + + >>> from sympy import Point3D, Line3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(1, 1, 1), Point3D(-1, 2, 0) + >>> l1, l2 = Line3D(p1, p2), Line3D(p2, p3) + >>> l1.angle_between(l2) + acos(-sqrt(2)/3) + >>> l1.smallest_angle_between(l2) + acos(sqrt(2)/3) + """ + if not isinstance(l1, LinearEntity) and not isinstance(l2, LinearEntity): + raise TypeError('Must pass only LinearEntity objects') + + v1, v2 = l1.direction, l2.direction + return acos(v1.dot(v2)/(abs(v1)*abs(v2))) + + def smallest_angle_between(l1, l2): + """Return the smallest angle formed at the intersection of the + lines containing the linear entities. + + Parameters + ========== + + l1 : LinearEntity + l2 : LinearEntity + + Returns + ======= + + angle : angle in radians + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2, p3 = Point(0, 0), Point(0, 4), Point(2, -2) + >>> l1, l2 = Line(p1, p2), Line(p1, p3) + >>> l1.smallest_angle_between(l2) + pi/4 + + See Also + ======== + + angle_between, is_perpendicular, Ray2D.closing_angle + """ + if not isinstance(l1, LinearEntity) and not isinstance(l2, LinearEntity): + raise TypeError('Must pass only LinearEntity objects') + + v1, v2 = l1.direction, l2.direction + return acos(abs(v1.dot(v2))/(abs(v1)*abs(v2))) + + def arbitrary_point(self, parameter='t'): + """A parameterized point on the Line. + + Parameters + ========== + + parameter : str, optional + The name of the parameter which will be used for the parametric + point. The default value is 't'. When this parameter is 0, the + first point used to define the line will be returned, and when + it is 1 the second point will be returned. + + Returns + ======= + + point : Point + + Raises + ====== + + ValueError + When ``parameter`` already appears in the Line's definition. + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(1, 0), Point(5, 3) + >>> l1 = Line(p1, p2) + >>> l1.arbitrary_point() + Point2D(4*t + 1, 3*t) + >>> from sympy import Point3D, Line3D + >>> p1, p2 = Point3D(1, 0, 0), Point3D(5, 3, 1) + >>> l1 = Line3D(p1, p2) + >>> l1.arbitrary_point() + Point3D(4*t + 1, 3*t, t) + + """ + t = _symbol(parameter, real=True) + if t.name in (f.name for f in self.free_symbols): + raise ValueError(filldedent(''' + Symbol %s already appears in object + and cannot be used as a parameter. + ''' % t.name)) + # multiply on the right so the variable gets + # combined with the coordinates of the point + return self.p1 + (self.p2 - self.p1)*t + + @staticmethod + def are_concurrent(*lines): + """Is a sequence of linear entities concurrent? + + Two or more linear entities are concurrent if they all + intersect at a single point. + + Parameters + ========== + + lines + A sequence of linear entities. + + Returns + ======= + + True : if the set of linear entities intersect in one point + False : otherwise. + + See Also + ======== + + sympy.geometry.util.intersection + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(3, 5) + >>> p3, p4 = Point(-2, -2), Point(0, 2) + >>> l1, l2, l3 = Line(p1, p2), Line(p1, p3), Line(p1, p4) + >>> Line.are_concurrent(l1, l2, l3) + True + >>> l4 = Line(p2, p3) + >>> Line.are_concurrent(l2, l3, l4) + False + >>> from sympy import Point3D, Line3D + >>> p1, p2 = Point3D(0, 0, 0), Point3D(3, 5, 2) + >>> p3, p4 = Point3D(-2, -2, -2), Point3D(0, 2, 1) + >>> l1, l2, l3 = Line3D(p1, p2), Line3D(p1, p3), Line3D(p1, p4) + >>> Line3D.are_concurrent(l1, l2, l3) + True + >>> l4 = Line3D(p2, p3) + >>> Line3D.are_concurrent(l2, l3, l4) + False + + """ + common_points = Intersection(*lines) + if common_points.is_FiniteSet and len(common_points) == 1: + return True + return False + + def contains(self, other): + """Subclasses should implement this method and should return + True if other is on the boundaries of self; + False if not on the boundaries of self; + None if a determination cannot be made.""" + raise NotImplementedError() + + @property + def direction(self): + """The direction vector of the LinearEntity. + + Returns + ======= + + p : a Point; the ray from the origin to this point is the + direction of `self` + + Examples + ======== + + >>> from sympy import Line + >>> a, b = (1, 1), (1, 3) + >>> Line(a, b).direction + Point2D(0, 2) + >>> Line(b, a).direction + Point2D(0, -2) + + This can be reported so the distance from the origin is 1: + + >>> Line(b, a).direction.unit + Point2D(0, -1) + + See Also + ======== + + sympy.geometry.point.Point.unit + + """ + return self.p2 - self.p1 + + def intersection(self, other): + """The intersection with another geometrical entity. + + Parameters + ========== + + o : Point or LinearEntity + + Returns + ======= + + intersection : list of geometrical entities + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Line, Segment + >>> p1, p2, p3 = Point(0, 0), Point(1, 1), Point(7, 7) + >>> l1 = Line(p1, p2) + >>> l1.intersection(p3) + [Point2D(7, 7)] + >>> p4, p5 = Point(5, 0), Point(0, 3) + >>> l2 = Line(p4, p5) + >>> l1.intersection(l2) + [Point2D(15/8, 15/8)] + >>> p6, p7 = Point(0, 5), Point(2, 6) + >>> s1 = Segment(p6, p7) + >>> l1.intersection(s1) + [] + >>> from sympy import Point3D, Line3D, Segment3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(1, 1, 1), Point3D(7, 7, 7) + >>> l1 = Line3D(p1, p2) + >>> l1.intersection(p3) + [Point3D(7, 7, 7)] + >>> l1 = Line3D(Point3D(4,19,12), Point3D(5,25,17)) + >>> l2 = Line3D(Point3D(-3, -15, -19), direction_ratio=[2,8,8]) + >>> l1.intersection(l2) + [Point3D(1, 1, -3)] + >>> p6, p7 = Point3D(0, 5, 2), Point3D(2, 6, 3) + >>> s1 = Segment3D(p6, p7) + >>> l1.intersection(s1) + [] + + """ + def intersect_parallel_rays(ray1, ray2): + if ray1.direction.dot(ray2.direction) > 0: + # rays point in the same direction + # so return the one that is "in front" + return [ray2] if ray1._span_test(ray2.p1) >= 0 else [ray1] + else: + # rays point in opposite directions + st = ray1._span_test(ray2.p1) + if st < 0: + return [] + elif st == 0: + return [ray2.p1] + return [Segment(ray1.p1, ray2.p1)] + + def intersect_parallel_ray_and_segment(ray, seg): + st1, st2 = ray._span_test(seg.p1), ray._span_test(seg.p2) + if st1 < 0 and st2 < 0: + return [] + elif st1 >= 0 and st2 >= 0: + return [seg] + elif st1 >= 0: # st2 < 0: + return [Segment(ray.p1, seg.p1)] + else: # st1 < 0 and st2 >= 0: + return [Segment(ray.p1, seg.p2)] + + def intersect_parallel_segments(seg1, seg2): + if seg1.contains(seg2): + return [seg2] + if seg2.contains(seg1): + return [seg1] + + # direct the segments so they're oriented the same way + if seg1.direction.dot(seg2.direction) < 0: + seg2 = Segment(seg2.p2, seg2.p1) + # order the segments so seg1 is "behind" seg2 + if seg1._span_test(seg2.p1) < 0: + seg1, seg2 = seg2, seg1 + if seg2._span_test(seg1.p2) < 0: + return [] + return [Segment(seg2.p1, seg1.p2)] + + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if other.is_Point: + if self.contains(other): + return [other] + else: + return [] + elif isinstance(other, LinearEntity): + # break into cases based on whether + # the lines are parallel, non-parallel intersecting, or skew + pts = Point._normalize_dimension(self.p1, self.p2, other.p1, other.p2) + rank = Point.affine_rank(*pts) + + if rank == 1: + # we're collinear + if isinstance(self, Line): + return [other] + if isinstance(other, Line): + return [self] + + if isinstance(self, Ray) and isinstance(other, Ray): + return intersect_parallel_rays(self, other) + if isinstance(self, Ray) and isinstance(other, Segment): + return intersect_parallel_ray_and_segment(self, other) + if isinstance(self, Segment) and isinstance(other, Ray): + return intersect_parallel_ray_and_segment(other, self) + if isinstance(self, Segment) and isinstance(other, Segment): + return intersect_parallel_segments(self, other) + elif rank == 2: + # we're in the same plane + l1 = Line(*pts[:2]) + l2 = Line(*pts[2:]) + + # check to see if we're parallel. If we are, we can't + # be intersecting, since the collinear case was already + # handled + if l1.direction.is_scalar_multiple(l2.direction): + return [] + + # find the intersection as if everything were lines + # by solving the equation t*d + p1 == s*d' + p1' + m = Matrix([l1.direction, -l2.direction]).transpose() + v = Matrix([l2.p1 - l1.p1]).transpose() + + # we cannot use m.solve(v) because that only works for square matrices + m_rref, pivots = m.col_insert(2, v).rref(simplify=True) + # rank == 2 ensures we have 2 pivots, but let's check anyway + if len(pivots) != 2: + raise GeometryError("Failed when solving Mx=b when M={} and b={}".format(m, v)) + coeff = m_rref[0, 2] + line_intersection = l1.direction*coeff + self.p1 + + # if both are lines, skip a containment check + if isinstance(self, Line) and isinstance(other, Line): + return [line_intersection] + + if ((isinstance(self, Line) or + self.contains(line_intersection)) and + other.contains(line_intersection)): + return [line_intersection] + if not self.atoms(Float) and not other.atoms(Float): + # if it can fail when there are no Floats then + # maybe the following parametric check should be + # done + return [] + # floats may fail exact containment so check that the + # arbitrary points, when equal, both give a + # non-negative parameter when the arbitrary point + # coordinates are equated + tu = solve(self.arbitrary_point(t) - other.arbitrary_point(u), + t, u, dict=True)[0] + def ok(p, l): + if isinstance(l, Line): + # p > -oo + return True + if isinstance(l, Ray): + # p >= 0 + return p.is_nonnegative + if isinstance(l, Segment): + # 0 <= p <= 1 + return p.is_nonnegative and (1 - p).is_nonnegative + raise ValueError("unexpected line type") + if ok(tu[t], self) and ok(tu[u], other): + return [line_intersection] + return [] + else: + # we're skew + return [] + + return other.intersection(self) + + def is_parallel(l1, l2): + """Are two linear entities parallel? + + Parameters + ========== + + l1 : LinearEntity + l2 : LinearEntity + + Returns + ======= + + True : if l1 and l2 are parallel, + False : otherwise. + + See Also + ======== + + coefficients + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(1, 1) + >>> p3, p4 = Point(3, 4), Point(6, 7) + >>> l1, l2 = Line(p1, p2), Line(p3, p4) + >>> Line.is_parallel(l1, l2) + True + >>> p5 = Point(6, 6) + >>> l3 = Line(p3, p5) + >>> Line.is_parallel(l1, l3) + False + >>> from sympy import Point3D, Line3D + >>> p1, p2 = Point3D(0, 0, 0), Point3D(3, 4, 5) + >>> p3, p4 = Point3D(2, 1, 1), Point3D(8, 9, 11) + >>> l1, l2 = Line3D(p1, p2), Line3D(p3, p4) + >>> Line3D.is_parallel(l1, l2) + True + >>> p5 = Point3D(6, 6, 6) + >>> l3 = Line3D(p3, p5) + >>> Line3D.is_parallel(l1, l3) + False + + """ + if not isinstance(l1, LinearEntity) and not isinstance(l2, LinearEntity): + raise TypeError('Must pass only LinearEntity objects') + + return l1.direction.is_scalar_multiple(l2.direction) + + def is_perpendicular(l1, l2): + """Are two linear entities perpendicular? + + Parameters + ========== + + l1 : LinearEntity + l2 : LinearEntity + + Returns + ======= + + True : if l1 and l2 are perpendicular, + False : otherwise. + + See Also + ======== + + coefficients + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2, p3 = Point(0, 0), Point(1, 1), Point(-1, 1) + >>> l1, l2 = Line(p1, p2), Line(p1, p3) + >>> l1.is_perpendicular(l2) + True + >>> p4 = Point(5, 3) + >>> l3 = Line(p1, p4) + >>> l1.is_perpendicular(l3) + False + >>> from sympy import Point3D, Line3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(1, 1, 1), Point3D(-1, 2, 0) + >>> l1, l2 = Line3D(p1, p2), Line3D(p2, p3) + >>> l1.is_perpendicular(l2) + False + >>> p4 = Point3D(5, 3, 7) + >>> l3 = Line3D(p1, p4) + >>> l1.is_perpendicular(l3) + False + + """ + if not isinstance(l1, LinearEntity) and not isinstance(l2, LinearEntity): + raise TypeError('Must pass only LinearEntity objects') + + return S.Zero.equals(l1.direction.dot(l2.direction)) + + def is_similar(self, other): + """ + Return True if self and other are contained in the same line. + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2, p3 = Point(0, 1), Point(3, 4), Point(2, 3) + >>> l1 = Line(p1, p2) + >>> l2 = Line(p1, p3) + >>> l1.is_similar(l2) + True + """ + l = Line(self.p1, self.p2) + return l.contains(other) + + @property + def length(self): + """ + The length of the line. + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(3, 5) + >>> l1 = Line(p1, p2) + >>> l1.length + oo + """ + return S.Infinity + + @property + def p1(self): + """The first defining point of a linear entity. + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(5, 3) + >>> l = Line(p1, p2) + >>> l.p1 + Point2D(0, 0) + + """ + return self.args[0] + + @property + def p2(self): + """The second defining point of a linear entity. + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(5, 3) + >>> l = Line(p1, p2) + >>> l.p2 + Point2D(5, 3) + + """ + return self.args[1] + + def parallel_line(self, p): + """Create a new Line parallel to this linear entity which passes + through the point `p`. + + Parameters + ========== + + p : Point + + Returns + ======= + + line : Line + + See Also + ======== + + is_parallel + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2, p3 = Point(0, 0), Point(2, 3), Point(-2, 2) + >>> l1 = Line(p1, p2) + >>> l2 = l1.parallel_line(p3) + >>> p3 in l2 + True + >>> l1.is_parallel(l2) + True + >>> from sympy import Point3D, Line3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(2, 3, 4), Point3D(-2, 2, 0) + >>> l1 = Line3D(p1, p2) + >>> l2 = l1.parallel_line(p3) + >>> p3 in l2 + True + >>> l1.is_parallel(l2) + True + + """ + p = Point(p, dim=self.ambient_dimension) + return Line(p, p + self.direction) + + def perpendicular_line(self, p): + """Create a new Line perpendicular to this linear entity which passes + through the point `p`. + + Parameters + ========== + + p : Point + + Returns + ======= + + line : Line + + See Also + ======== + + sympy.geometry.line.LinearEntity.is_perpendicular, perpendicular_segment + + Examples + ======== + + >>> from sympy import Point3D, Line3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(2, 3, 4), Point3D(-2, 2, 0) + >>> L = Line3D(p1, p2) + >>> P = L.perpendicular_line(p3); P + Line3D(Point3D(-2, 2, 0), Point3D(4/29, 6/29, 8/29)) + >>> L.is_perpendicular(P) + True + + In 3D the, the first point used to define the line is the point + through which the perpendicular was required to pass; the + second point is (arbitrarily) contained in the given line: + + >>> P.p2 in L + True + """ + p = Point(p, dim=self.ambient_dimension) + if p in self: + p = p + self.direction.orthogonal_direction + return Line(p, self.projection(p)) + + def perpendicular_segment(self, p): + """Create a perpendicular line segment from `p` to this line. + + The endpoints of the segment are ``p`` and the closest point in + the line containing self. (If self is not a line, the point might + not be in self.) + + Parameters + ========== + + p : Point + + Returns + ======= + + segment : Segment + + Notes + ===== + + Returns `p` itself if `p` is on this linear entity. + + See Also + ======== + + perpendicular_line + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2, p3 = Point(0, 0), Point(1, 1), Point(0, 2) + >>> l1 = Line(p1, p2) + >>> s1 = l1.perpendicular_segment(p3) + >>> l1.is_perpendicular(s1) + True + >>> p3 in s1 + True + >>> l1.perpendicular_segment(Point(4, 0)) + Segment2D(Point2D(4, 0), Point2D(2, 2)) + >>> from sympy import Point3D, Line3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(1, 1, 1), Point3D(0, 2, 0) + >>> l1 = Line3D(p1, p2) + >>> s1 = l1.perpendicular_segment(p3) + >>> l1.is_perpendicular(s1) + True + >>> p3 in s1 + True + >>> l1.perpendicular_segment(Point3D(4, 0, 0)) + Segment3D(Point3D(4, 0, 0), Point3D(4/3, 4/3, 4/3)) + + """ + p = Point(p, dim=self.ambient_dimension) + if p in self: + return p + l = self.perpendicular_line(p) + # The intersection should be unique, so unpack the singleton + p2, = Intersection(Line(self.p1, self.p2), l) + + return Segment(p, p2) + + @property + def points(self): + """The two points used to define this linear entity. + + Returns + ======= + + points : tuple of Points + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(5, 11) + >>> l1 = Line(p1, p2) + >>> l1.points + (Point2D(0, 0), Point2D(5, 11)) + + """ + return (self.p1, self.p2) + + def projection(self, other): + """Project a point, line, ray, or segment onto this linear entity. + + Parameters + ========== + + other : Point or LinearEntity (Line, Ray, Segment) + + Returns + ======= + + projection : Point or LinearEntity (Line, Ray, Segment) + The return type matches the type of the parameter ``other``. + + Raises + ====== + + GeometryError + When method is unable to perform projection. + + Notes + ===== + + A projection involves taking the two points that define + the linear entity and projecting those points onto a + Line and then reforming the linear entity using these + projections. + A point P is projected onto a line L by finding the point + on L that is closest to P. This point is the intersection + of L and the line perpendicular to L that passes through P. + + See Also + ======== + + sympy.geometry.point.Point, perpendicular_line + + Examples + ======== + + >>> from sympy import Point, Line, Segment, Rational + >>> p1, p2, p3 = Point(0, 0), Point(1, 1), Point(Rational(1, 2), 0) + >>> l1 = Line(p1, p2) + >>> l1.projection(p3) + Point2D(1/4, 1/4) + >>> p4, p5 = Point(10, 0), Point(12, 1) + >>> s1 = Segment(p4, p5) + >>> l1.projection(s1) + Segment2D(Point2D(5, 5), Point2D(13/2, 13/2)) + >>> p1, p2, p3 = Point(0, 0, 1), Point(1, 1, 2), Point(2, 0, 1) + >>> l1 = Line(p1, p2) + >>> l1.projection(p3) + Point3D(2/3, 2/3, 5/3) + >>> p4, p5 = Point(10, 0, 1), Point(12, 1, 3) + >>> s1 = Segment(p4, p5) + >>> l1.projection(s1) + Segment3D(Point3D(10/3, 10/3, 13/3), Point3D(5, 5, 6)) + + """ + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + + def proj_point(p): + return Point.project(p - self.p1, self.direction) + self.p1 + + if isinstance(other, Point): + return proj_point(other) + elif isinstance(other, LinearEntity): + p1, p2 = proj_point(other.p1), proj_point(other.p2) + # test to see if we're degenerate + if p1 == p2: + return p1 + projected = other.__class__(p1, p2) + projected = Intersection(self, projected) + if projected.is_empty: + return projected + # if we happen to have intersected in only a point, return that + if projected.is_FiniteSet and len(projected) == 1: + # projected is a set of size 1, so unpack it in `a` + a, = projected + return a + # order args so projection is in the same direction as self + if self.direction.dot(projected.direction) < 0: + p1, p2 = projected.args + projected = projected.func(p2, p1) + return projected + + raise GeometryError( + "Do not know how to project %s onto %s" % (other, self)) + + def random_point(self, seed=None): + """A random point on a LinearEntity. + + Returns + ======= + + point : Point + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Line, Ray, Segment + >>> p1, p2 = Point(0, 0), Point(5, 3) + >>> line = Line(p1, p2) + >>> r = line.random_point(seed=42) # seed value is optional + >>> r.n(3) + Point2D(-0.72, -0.432) + >>> r in line + True + >>> Ray(p1, p2).random_point(seed=42).n(3) + Point2D(0.72, 0.432) + >>> Segment(p1, p2).random_point(seed=42).n(3) + Point2D(3.2, 1.92) + + """ + if seed is not None: + rng = random.Random(seed) + else: + rng = random + pt = self.arbitrary_point(t) + if isinstance(self, Ray): + v = abs(rng.gauss(0, 1)) + elif isinstance(self, Segment): + v = rng.random() + elif isinstance(self, Line): + v = rng.gauss(0, 1) + else: + raise NotImplementedError('unhandled line type') + return pt.subs(t, Rational(v)) + + def bisectors(self, other): + """Returns the perpendicular lines which pass through the intersections + of self and other that are in the same plane. + + Parameters + ========== + + line : Line3D + + Returns + ======= + + list: two Line instances + + Examples + ======== + + >>> from sympy import Point3D, Line3D + >>> r1 = Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0)) + >>> r2 = Line3D(Point3D(0, 0, 0), Point3D(0, 1, 0)) + >>> r1.bisectors(r2) + [Line3D(Point3D(0, 0, 0), Point3D(1, 1, 0)), Line3D(Point3D(0, 0, 0), Point3D(1, -1, 0))] + + """ + if not isinstance(other, LinearEntity): + raise GeometryError("Expecting LinearEntity, not %s" % other) + + l1, l2 = self, other + + # make sure dimensions match or else a warning will rise from + # intersection calculation + if l1.p1.ambient_dimension != l2.p1.ambient_dimension: + if isinstance(l1, Line2D): + l1, l2 = l2, l1 + _, p1 = Point._normalize_dimension(l1.p1, l2.p1, on_morph='ignore') + _, p2 = Point._normalize_dimension(l1.p2, l2.p2, on_morph='ignore') + l2 = Line(p1, p2) + + point = intersection(l1, l2) + + # Three cases: Lines may intersect in a point, may be equal or may not intersect. + if not point: + raise GeometryError("The lines do not intersect") + else: + pt = point[0] + if isinstance(pt, Line): + # Intersection is a line because both lines are coincident + return [self] + + + d1 = l1.direction.unit + d2 = l2.direction.unit + + bis1 = Line(pt, pt + d1 + d2) + bis2 = Line(pt, pt + d1 - d2) + + return [bis1, bis2] + + +class Line(LinearEntity): + """An infinite line in space. + + A 2D line is declared with two distinct points, point and slope, or + an equation. A 3D line may be defined with a point and a direction ratio. + + Parameters + ========== + + p1 : Point + p2 : Point + slope : SymPy expression + direction_ratio : list + equation : equation of a line + + Notes + ===== + + `Line` will automatically subclass to `Line2D` or `Line3D` based + on the dimension of `p1`. The `slope` argument is only relevant + for `Line2D` and the `direction_ratio` argument is only relevant + for `Line3D`. + + The order of the points will define the direction of the line + which is used when calculating the angle between lines. + + See Also + ======== + + sympy.geometry.point.Point + sympy.geometry.line.Line2D + sympy.geometry.line.Line3D + + Examples + ======== + + >>> from sympy import Line, Segment, Point, Eq + >>> from sympy.abc import x, y, a, b + + >>> L = Line(Point(2,3), Point(3,5)) + >>> L + Line2D(Point2D(2, 3), Point2D(3, 5)) + >>> L.points + (Point2D(2, 3), Point2D(3, 5)) + >>> L.equation() + -2*x + y + 1 + >>> L.coefficients + (-2, 1, 1) + + Instantiate with keyword ``slope``: + + >>> Line(Point(0, 0), slope=0) + Line2D(Point2D(0, 0), Point2D(1, 0)) + + Instantiate with another linear object + + >>> s = Segment((0, 0), (0, 1)) + >>> Line(s).equation() + x + + The line corresponding to an equation in the for `ax + by + c = 0`, + can be entered: + + >>> Line(3*x + y + 18) + Line2D(Point2D(0, -18), Point2D(1, -21)) + + If `x` or `y` has a different name, then they can be specified, too, + as a string (to match the name) or symbol: + + >>> Line(Eq(3*a + b, -18), x='a', y=b) + Line2D(Point2D(0, -18), Point2D(1, -21)) + """ + def __new__(cls, *args, **kwargs): + if len(args) == 1 and isinstance(args[0], (Expr, Eq)): + missing = uniquely_named_symbol('?', args) + if not kwargs: + x = 'x' + y = 'y' + else: + x = kwargs.pop('x', missing) + y = kwargs.pop('y', missing) + if kwargs: + raise ValueError('expecting only x and y as keywords') + + equation = args[0] + if isinstance(equation, Eq): + equation = equation.lhs - equation.rhs + + def find_or_missing(x): + try: + return find(x, equation) + except ValueError: + return missing + x = find_or_missing(x) + y = find_or_missing(y) + + a, b, c = linear_coeffs(equation, x, y) + + if b: + return Line((0, -c/b), slope=-a/b) + if a: + return Line((-c/a, 0), slope=oo) + + raise ValueError('not found in equation: %s' % (set('xy') - {x, y})) + + else: + if len(args) > 0: + p1 = args[0] + if len(args) > 1: + p2 = args[1] + else: + p2 = None + + if isinstance(p1, LinearEntity): + if p2: + raise ValueError('If p1 is a LinearEntity, p2 must be None.') + dim = len(p1.p1) + else: + p1 = Point(p1) + dim = len(p1) + if p2 is not None or isinstance(p2, Point) and p2.ambient_dimension != dim: + p2 = Point(p2) + + if dim == 2: + return Line2D(p1, p2, **kwargs) + elif dim == 3: + return Line3D(p1, p2, **kwargs) + return LinearEntity.__new__(cls, p1, p2, **kwargs) + + def contains(self, other): + """ + Return True if `other` is on this Line, or False otherwise. + + Examples + ======== + + >>> from sympy import Line,Point + >>> p1, p2 = Point(0, 1), Point(3, 4) + >>> l = Line(p1, p2) + >>> l.contains(p1) + True + >>> l.contains((0, 1)) + True + >>> l.contains((0, 0)) + False + >>> a = (0, 0, 0) + >>> b = (1, 1, 1) + >>> c = (2, 2, 2) + >>> l1 = Line(a, b) + >>> l2 = Line(b, a) + >>> l1 == l2 + False + >>> l1 in l2 + True + + """ + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if isinstance(other, Point): + return Point.is_collinear(other, self.p1, self.p2) + if isinstance(other, LinearEntity): + return Point.is_collinear(self.p1, self.p2, other.p1, other.p2) + return False + + def distance(self, other): + """ + Finds the shortest distance between a line and a point. + + Raises + ====== + + NotImplementedError is raised if `other` is not a Point + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(1, 1) + >>> s = Line(p1, p2) + >>> s.distance(Point(-1, 1)) + sqrt(2) + >>> s.distance((-1, 2)) + 3*sqrt(2)/2 + >>> p1, p2 = Point(0, 0, 0), Point(1, 1, 1) + >>> s = Line(p1, p2) + >>> s.distance(Point(-1, 1, 1)) + 2*sqrt(6)/3 + >>> s.distance((-1, 1, 1)) + 2*sqrt(6)/3 + + """ + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if self.contains(other): + return S.Zero + return self.perpendicular_segment(other).length + + def equals(self, other): + """Returns True if self and other are the same mathematical entities""" + if not isinstance(other, Line): + return False + return Point.is_collinear(self.p1, other.p1, self.p2, other.p2) + + def plot_interval(self, parameter='t'): + """The plot interval for the default geometric plot of line. Gives + values that will produce a line that is +/- 5 units long (where a + unit is the distance between the two points that define the line). + + Parameters + ========== + + parameter : str, optional + Default value is 't'. + + Returns + ======= + + plot_interval : list (plot interval) + [parameter, lower_bound, upper_bound] + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(5, 3) + >>> l1 = Line(p1, p2) + >>> l1.plot_interval() + [t, -5, 5] + + """ + t = _symbol(parameter, real=True) + return [t, -5, 5] + + +class Ray(LinearEntity): + """A Ray is a semi-line in the space with a source point and a direction. + + Parameters + ========== + + p1 : Point + The source of the Ray + p2 : Point or radian value + This point determines the direction in which the Ray propagates. + If given as an angle it is interpreted in radians with the positive + direction being ccw. + + Attributes + ========== + + source + + See Also + ======== + + sympy.geometry.line.Ray2D + sympy.geometry.line.Ray3D + sympy.geometry.point.Point + sympy.geometry.line.Line + + Notes + ===== + + `Ray` will automatically subclass to `Ray2D` or `Ray3D` based on the + dimension of `p1`. + + Examples + ======== + + >>> from sympy import Ray, Point, pi + >>> r = Ray(Point(2, 3), Point(3, 5)) + >>> r + Ray2D(Point2D(2, 3), Point2D(3, 5)) + >>> r.points + (Point2D(2, 3), Point2D(3, 5)) + >>> r.source + Point2D(2, 3) + >>> r.xdirection + oo + >>> r.ydirection + oo + >>> r.slope + 2 + >>> Ray(Point(0, 0), angle=pi/4).slope + 1 + + """ + def __new__(cls, p1, p2=None, **kwargs): + p1 = Point(p1) + if p2 is not None: + p1, p2 = Point._normalize_dimension(p1, Point(p2)) + dim = len(p1) + + if dim == 2: + return Ray2D(p1, p2, **kwargs) + elif dim == 3: + return Ray3D(p1, p2, **kwargs) + return LinearEntity.__new__(cls, p1, p2, **kwargs) + + def _svg(self, scale_factor=1., fill_color="#66cc99"): + """Returns SVG path element for the LinearEntity. + + Parameters + ========== + + scale_factor : float + Multiplication factor for the SVG stroke-width. Default is 1. + fill_color : str, optional + Hex string for fill color. Default is "#66cc99". + """ + verts = (N(self.p1), N(self.p2)) + coords = ["{},{}".format(p.x, p.y) for p in verts] + path = "M {} L {}".format(coords[0], " L ".join(coords[1:])) + + return ( + '' + ).format(2.*scale_factor, path, fill_color) + + def contains(self, other): + """ + Is other GeometryEntity contained in this Ray? + + Examples + ======== + + >>> from sympy import Ray,Point,Segment + >>> p1, p2 = Point(0, 0), Point(4, 4) + >>> r = Ray(p1, p2) + >>> r.contains(p1) + True + >>> r.contains((1, 1)) + True + >>> r.contains((1, 3)) + False + >>> s = Segment((1, 1), (2, 2)) + >>> r.contains(s) + True + >>> s = Segment((1, 2), (2, 5)) + >>> r.contains(s) + False + >>> r1 = Ray((2, 2), (3, 3)) + >>> r.contains(r1) + True + >>> r1 = Ray((2, 2), (3, 5)) + >>> r.contains(r1) + False + """ + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if isinstance(other, Point): + if Point.is_collinear(self.p1, self.p2, other): + # if we're in the direction of the ray, our + # direction vector dot the ray's direction vector + # should be non-negative + return bool((self.p2 - self.p1).dot(other - self.p1) >= S.Zero) + return False + elif isinstance(other, Ray): + if Point.is_collinear(self.p1, self.p2, other.p1, other.p2): + return bool((self.p2 - self.p1).dot(other.p2 - other.p1) > S.Zero) + return False + elif isinstance(other, Segment): + return other.p1 in self and other.p2 in self + + # No other known entity can be contained in a Ray + return False + + def distance(self, other): + """ + Finds the shortest distance between the ray and a point. + + Raises + ====== + + NotImplementedError is raised if `other` is not a Point + + Examples + ======== + + >>> from sympy import Point, Ray + >>> p1, p2 = Point(0, 0), Point(1, 1) + >>> s = Ray(p1, p2) + >>> s.distance(Point(-1, -1)) + sqrt(2) + >>> s.distance((-1, 2)) + 3*sqrt(2)/2 + >>> p1, p2 = Point(0, 0, 0), Point(1, 1, 2) + >>> s = Ray(p1, p2) + >>> s + Ray3D(Point3D(0, 0, 0), Point3D(1, 1, 2)) + >>> s.distance(Point(-1, -1, 2)) + 4*sqrt(3)/3 + >>> s.distance((-1, -1, 2)) + 4*sqrt(3)/3 + + """ + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if self.contains(other): + return S.Zero + + proj = Line(self.p1, self.p2).projection(other) + if self.contains(proj): + return abs(other - proj) + else: + return abs(other - self.source) + + def equals(self, other): + """Returns True if self and other are the same mathematical entities""" + if not isinstance(other, Ray): + return False + return self.source == other.source and other.p2 in self + + def plot_interval(self, parameter='t'): + """The plot interval for the default geometric plot of the Ray. Gives + values that will produce a ray that is 10 units long (where a unit is + the distance between the two points that define the ray). + + Parameters + ========== + + parameter : str, optional + Default value is 't'. + + Returns + ======= + + plot_interval : list + [parameter, lower_bound, upper_bound] + + Examples + ======== + + >>> from sympy import Ray, pi + >>> r = Ray((0, 0), angle=pi/4) + >>> r.plot_interval() + [t, 0, 10] + + """ + t = _symbol(parameter, real=True) + return [t, 0, 10] + + @property + def source(self): + """The point from which the ray emanates. + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Ray + >>> p1, p2 = Point(0, 0), Point(4, 1) + >>> r1 = Ray(p1, p2) + >>> r1.source + Point2D(0, 0) + >>> p1, p2 = Point(0, 0, 0), Point(4, 1, 5) + >>> r1 = Ray(p2, p1) + >>> r1.source + Point3D(4, 1, 5) + + """ + return self.p1 + + +class Segment(LinearEntity): + """A line segment in space. + + Parameters + ========== + + p1 : Point + p2 : Point + + Attributes + ========== + + length : number or SymPy expression + midpoint : Point + + See Also + ======== + + sympy.geometry.line.Segment2D + sympy.geometry.line.Segment3D + sympy.geometry.point.Point + sympy.geometry.line.Line + + Notes + ===== + + If 2D or 3D points are used to define `Segment`, it will + be automatically subclassed to `Segment2D` or `Segment3D`. + + Examples + ======== + + >>> from sympy import Point, Segment + >>> Segment((1, 0), (1, 1)) # tuples are interpreted as pts + Segment2D(Point2D(1, 0), Point2D(1, 1)) + >>> s = Segment(Point(4, 3), Point(1, 1)) + >>> s.points + (Point2D(4, 3), Point2D(1, 1)) + >>> s.slope + 2/3 + >>> s.length + sqrt(13) + >>> s.midpoint + Point2D(5/2, 2) + >>> Segment((1, 0, 0), (1, 1, 1)) # tuples are interpreted as pts + Segment3D(Point3D(1, 0, 0), Point3D(1, 1, 1)) + >>> s = Segment(Point(4, 3, 9), Point(1, 1, 7)); s + Segment3D(Point3D(4, 3, 9), Point3D(1, 1, 7)) + >>> s.points + (Point3D(4, 3, 9), Point3D(1, 1, 7)) + >>> s.length + sqrt(17) + >>> s.midpoint + Point3D(5/2, 2, 8) + + """ + def __new__(cls, p1, p2, **kwargs): + p1, p2 = Point._normalize_dimension(Point(p1), Point(p2)) + dim = len(p1) + + if dim == 2: + return Segment2D(p1, p2, **kwargs) + elif dim == 3: + return Segment3D(p1, p2, **kwargs) + return LinearEntity.__new__(cls, p1, p2, **kwargs) + + def contains(self, other): + """ + Is the other GeometryEntity contained within this Segment? + + Examples + ======== + + >>> from sympy import Point, Segment + >>> p1, p2 = Point(0, 1), Point(3, 4) + >>> s = Segment(p1, p2) + >>> s2 = Segment(p2, p1) + >>> s.contains(s2) + True + >>> from sympy import Point3D, Segment3D + >>> p1, p2 = Point3D(0, 1, 1), Point3D(3, 4, 5) + >>> s = Segment3D(p1, p2) + >>> s2 = Segment3D(p2, p1) + >>> s.contains(s2) + True + >>> s.contains((p1 + p2)/2) + True + """ + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if isinstance(other, Point): + if Point.is_collinear(other, self.p1, self.p2): + if isinstance(self, Segment2D): + # if it is collinear and is in the bounding box of the + # segment then it must be on the segment + vert = (1/self.slope).equals(0) + if vert is False: + isin = (self.p1.x - other.x)*(self.p2.x - other.x) <= 0 + if isin in (True, False): + return isin + if vert is True: + isin = (self.p1.y - other.y)*(self.p2.y - other.y) <= 0 + if isin in (True, False): + return isin + # use the triangle inequality + d1, d2 = other - self.p1, other - self.p2 + d = self.p2 - self.p1 + # without the call to simplify, SymPy cannot tell that an expression + # like (a+b)*(a/2+b/2) is always non-negative. If it cannot be + # determined, raise an Undecidable error + try: + # the triangle inequality says that |d1|+|d2| >= |d| and is strict + # only if other lies in the line segment + return bool(simplify(Eq(abs(d1) + abs(d2) - abs(d), 0))) + except TypeError: + raise Undecidable("Cannot determine if {} is in {}".format(other, self)) + if isinstance(other, Segment): + return other.p1 in self and other.p2 in self + + return False + + def equals(self, other): + """Returns True if self and other are the same mathematical entities""" + return isinstance(other, self.func) and list( + ordered(self.args)) == list(ordered(other.args)) + + def distance(self, other): + """ + Finds the shortest distance between a line segment and a point. + + Raises + ====== + + NotImplementedError is raised if `other` is not a Point + + Examples + ======== + + >>> from sympy import Point, Segment + >>> p1, p2 = Point(0, 1), Point(3, 4) + >>> s = Segment(p1, p2) + >>> s.distance(Point(10, 15)) + sqrt(170) + >>> s.distance((0, 12)) + sqrt(73) + >>> from sympy import Point3D, Segment3D + >>> p1, p2 = Point3D(0, 0, 3), Point3D(1, 1, 4) + >>> s = Segment3D(p1, p2) + >>> s.distance(Point3D(10, 15, 12)) + sqrt(341) + >>> s.distance((10, 15, 12)) + sqrt(341) + """ + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if isinstance(other, Point): + vp1 = other - self.p1 + vp2 = other - self.p2 + + dot_prod_sign_1 = self.direction.dot(vp1) >= 0 + dot_prod_sign_2 = self.direction.dot(vp2) <= 0 + if dot_prod_sign_1 and dot_prod_sign_2: + return Line(self.p1, self.p2).distance(other) + if dot_prod_sign_1 and not dot_prod_sign_2: + return abs(vp2) + if not dot_prod_sign_1 and dot_prod_sign_2: + return abs(vp1) + raise NotImplementedError() + + @property + def length(self): + """The length of the line segment. + + See Also + ======== + + sympy.geometry.point.Point.distance + + Examples + ======== + + >>> from sympy import Point, Segment + >>> p1, p2 = Point(0, 0), Point(4, 3) + >>> s1 = Segment(p1, p2) + >>> s1.length + 5 + >>> from sympy import Point3D, Segment3D + >>> p1, p2 = Point3D(0, 0, 0), Point3D(4, 3, 3) + >>> s1 = Segment3D(p1, p2) + >>> s1.length + sqrt(34) + + """ + return Point.distance(self.p1, self.p2) + + @property + def midpoint(self): + """The midpoint of the line segment. + + See Also + ======== + + sympy.geometry.point.Point.midpoint + + Examples + ======== + + >>> from sympy import Point, Segment + >>> p1, p2 = Point(0, 0), Point(4, 3) + >>> s1 = Segment(p1, p2) + >>> s1.midpoint + Point2D(2, 3/2) + >>> from sympy import Point3D, Segment3D + >>> p1, p2 = Point3D(0, 0, 0), Point3D(4, 3, 3) + >>> s1 = Segment3D(p1, p2) + >>> s1.midpoint + Point3D(2, 3/2, 3/2) + + """ + return Point.midpoint(self.p1, self.p2) + + def perpendicular_bisector(self, p=None): + """The perpendicular bisector of this segment. + + If no point is specified or the point specified is not on the + bisector then the bisector is returned as a Line. Otherwise a + Segment is returned that joins the point specified and the + intersection of the bisector and the segment. + + Parameters + ========== + + p : Point + + Returns + ======= + + bisector : Line or Segment + + See Also + ======== + + LinearEntity.perpendicular_segment + + Examples + ======== + + >>> from sympy import Point, Segment + >>> p1, p2, p3 = Point(0, 0), Point(6, 6), Point(5, 1) + >>> s1 = Segment(p1, p2) + >>> s1.perpendicular_bisector() + Line2D(Point2D(3, 3), Point2D(-3, 9)) + + >>> s1.perpendicular_bisector(p3) + Segment2D(Point2D(5, 1), Point2D(3, 3)) + + """ + l = self.perpendicular_line(self.midpoint) + if p is not None: + p2 = Point(p, dim=self.ambient_dimension) + if p2 in l: + return Segment(p2, self.midpoint) + return l + + def plot_interval(self, parameter='t'): + """The plot interval for the default geometric plot of the Segment gives + values that will produce the full segment in a plot. + + Parameters + ========== + + parameter : str, optional + Default value is 't'. + + Returns + ======= + + plot_interval : list + [parameter, lower_bound, upper_bound] + + Examples + ======== + + >>> from sympy import Point, Segment + >>> p1, p2 = Point(0, 0), Point(5, 3) + >>> s1 = Segment(p1, p2) + >>> s1.plot_interval() + [t, 0, 1] + + """ + t = _symbol(parameter, real=True) + return [t, 0, 1] + + +class LinearEntity2D(LinearEntity): + """A base class for all linear entities (line, ray and segment) + in a 2-dimensional Euclidean space. + + Attributes + ========== + + p1 + p2 + coefficients + slope + points + + Notes + ===== + + This is an abstract class and is not meant to be instantiated. + + See Also + ======== + + sympy.geometry.entity.GeometryEntity + + """ + @property + def bounds(self): + """Return a tuple (xmin, ymin, xmax, ymax) representing the bounding + rectangle for the geometric figure. + + """ + verts = self.points + xs = [p.x for p in verts] + ys = [p.y for p in verts] + return (min(xs), min(ys), max(xs), max(ys)) + + def perpendicular_line(self, p): + """Create a new Line perpendicular to this linear entity which passes + through the point `p`. + + Parameters + ========== + + p : Point + + Returns + ======= + + line : Line + + See Also + ======== + + sympy.geometry.line.LinearEntity.is_perpendicular, perpendicular_segment + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2, p3 = Point(0, 0), Point(2, 3), Point(-2, 2) + >>> L = Line(p1, p2) + >>> P = L.perpendicular_line(p3); P + Line2D(Point2D(-2, 2), Point2D(-5, 4)) + >>> L.is_perpendicular(P) + True + + In 2D, the first point of the perpendicular line is the + point through which was required to pass; the second + point is arbitrarily chosen. To get a line that explicitly + uses a point in the line, create a line from the perpendicular + segment from the line to the point: + + >>> Line(L.perpendicular_segment(p3)) + Line2D(Point2D(-2, 2), Point2D(4/13, 6/13)) + """ + p = Point(p, dim=self.ambient_dimension) + # any two lines in R^2 intersect, so blindly making + # a line through p in an orthogonal direction will work + # and is faster than finding the projection point as in 3D + return Line(p, p + self.direction.orthogonal_direction) + + @property + def slope(self): + """The slope of this linear entity, or infinity if vertical. + + Returns + ======= + + slope : number or SymPy expression + + See Also + ======== + + coefficients + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(0, 0), Point(3, 5) + >>> l1 = Line(p1, p2) + >>> l1.slope + 5/3 + + >>> p3 = Point(0, 4) + >>> l2 = Line(p1, p3) + >>> l2.slope + oo + + """ + d1, d2 = (self.p1 - self.p2).args + if d1 == 0: + return S.Infinity + return simplify(d2/d1) + + +class Line2D(LinearEntity2D, Line): + """An infinite line in space 2D. + + A line is declared with two distinct points or a point and slope + as defined using keyword `slope`. + + Parameters + ========== + + p1 : Point + pt : Point + slope : SymPy expression + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Line, Segment, Point + >>> L = Line(Point(2,3), Point(3,5)) + >>> L + Line2D(Point2D(2, 3), Point2D(3, 5)) + >>> L.points + (Point2D(2, 3), Point2D(3, 5)) + >>> L.equation() + -2*x + y + 1 + >>> L.coefficients + (-2, 1, 1) + + Instantiate with keyword ``slope``: + + >>> Line(Point(0, 0), slope=0) + Line2D(Point2D(0, 0), Point2D(1, 0)) + + Instantiate with another linear object + + >>> s = Segment((0, 0), (0, 1)) + >>> Line(s).equation() + x + """ + def __new__(cls, p1, pt=None, slope=None, **kwargs): + if isinstance(p1, LinearEntity): + if pt is not None: + raise ValueError('When p1 is a LinearEntity, pt should be None') + p1, pt = Point._normalize_dimension(*p1.args, dim=2) + else: + p1 = Point(p1, dim=2) + if pt is not None and slope is None: + try: + p2 = Point(pt, dim=2) + except (NotImplementedError, TypeError, ValueError): + raise ValueError(filldedent(''' + The 2nd argument was not a valid Point. + If it was a slope, enter it with keyword "slope". + ''')) + elif slope is not None and pt is None: + slope = sympify(slope) + if slope.is_finite is False: + # when infinite slope, don't change x + dx = 0 + dy = 1 + else: + # go over 1 up slope + dx = 1 + dy = slope + # XXX avoiding simplification by adding to coords directly + p2 = Point(p1.x + dx, p1.y + dy, evaluate=False) + else: + raise ValueError('A 2nd Point or keyword "slope" must be used.') + return LinearEntity2D.__new__(cls, p1, p2, **kwargs) + + def _svg(self, scale_factor=1., fill_color="#66cc99"): + """Returns SVG path element for the LinearEntity. + + Parameters + ========== + + scale_factor : float + Multiplication factor for the SVG stroke-width. Default is 1. + fill_color : str, optional + Hex string for fill color. Default is "#66cc99". + """ + verts = (N(self.p1), N(self.p2)) + coords = ["{},{}".format(p.x, p.y) for p in verts] + path = "M {} L {}".format(coords[0], " L ".join(coords[1:])) + + return ( + '' + ).format(2.*scale_factor, path, fill_color) + + @property + def coefficients(self): + """The coefficients (`a`, `b`, `c`) for `ax + by + c = 0`. + + See Also + ======== + + sympy.geometry.line.Line2D.equation + + Examples + ======== + + >>> from sympy import Point, Line + >>> from sympy.abc import x, y + >>> p1, p2 = Point(0, 0), Point(5, 3) + >>> l = Line(p1, p2) + >>> l.coefficients + (-3, 5, 0) + + >>> p3 = Point(x, y) + >>> l2 = Line(p1, p3) + >>> l2.coefficients + (-y, x, 0) + + """ + p1, p2 = self.points + if p1.x == p2.x: + return (S.One, S.Zero, -p1.x) + elif p1.y == p2.y: + return (S.Zero, S.One, -p1.y) + return tuple([simplify(i) for i in + (self.p1.y - self.p2.y, + self.p2.x - self.p1.x, + self.p1.x*self.p2.y - self.p1.y*self.p2.x)]) + + def equation(self, x='x', y='y'): + """The equation of the line: ax + by + c. + + Parameters + ========== + + x : str, optional + The name to use for the x-axis, default value is 'x'. + y : str, optional + The name to use for the y-axis, default value is 'y'. + + Returns + ======= + + equation : SymPy expression + + See Also + ======== + + sympy.geometry.line.Line2D.coefficients + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(1, 0), Point(5, 3) + >>> l1 = Line(p1, p2) + >>> l1.equation() + -3*x + 4*y + 3 + + """ + x = _symbol(x, real=True) + y = _symbol(y, real=True) + p1, p2 = self.points + if p1.x == p2.x: + return x - p1.x + elif p1.y == p2.y: + return y - p1.y + + a, b, c = self.coefficients + return a*x + b*y + c + + +class Ray2D(LinearEntity2D, Ray): + """ + A Ray is a semi-line in the space with a source point and a direction. + + Parameters + ========== + + p1 : Point + The source of the Ray + p2 : Point or radian value + This point determines the direction in which the Ray propagates. + If given as an angle it is interpreted in radians with the positive + direction being ccw. + + Attributes + ========== + + source + xdirection + ydirection + + See Also + ======== + + sympy.geometry.point.Point, Line + + Examples + ======== + + >>> from sympy import Point, pi, Ray + >>> r = Ray(Point(2, 3), Point(3, 5)) + >>> r + Ray2D(Point2D(2, 3), Point2D(3, 5)) + >>> r.points + (Point2D(2, 3), Point2D(3, 5)) + >>> r.source + Point2D(2, 3) + >>> r.xdirection + oo + >>> r.ydirection + oo + >>> r.slope + 2 + >>> Ray(Point(0, 0), angle=pi/4).slope + 1 + + """ + def __new__(cls, p1, pt=None, angle=None, **kwargs): + p1 = Point(p1, dim=2) + if pt is not None and angle is None: + try: + p2 = Point(pt, dim=2) + except (NotImplementedError, TypeError, ValueError): + raise ValueError(filldedent(''' + The 2nd argument was not a valid Point; if + it was meant to be an angle it should be + given with keyword "angle".''')) + if p1 == p2: + raise ValueError('A Ray requires two distinct points.') + elif angle is not None and pt is None: + # we need to know if the angle is an odd multiple of pi/2 + angle = sympify(angle) + c = _pi_coeff(angle) + p2 = None + if c is not None: + if c.is_Rational: + if c.q == 2: + if c.p == 1: + p2 = p1 + Point(0, 1) + elif c.p == 3: + p2 = p1 + Point(0, -1) + elif c.q == 1: + if c.p == 0: + p2 = p1 + Point(1, 0) + elif c.p == 1: + p2 = p1 + Point(-1, 0) + if p2 is None: + c *= S.Pi + else: + c = angle % (2*S.Pi) + if not p2: + m = 2*c/S.Pi + left = And(1 < m, m < 3) # is it in quadrant 2 or 3? + x = Piecewise((-1, left), (Piecewise((0, Eq(m % 1, 0)), (1, True)), True)) + y = Piecewise((-tan(c), left), (Piecewise((1, Eq(m, 1)), (-1, Eq(m, 3)), (tan(c), True)), True)) + p2 = p1 + Point(x, y) + else: + raise ValueError('A 2nd point or keyword "angle" must be used.') + + return LinearEntity2D.__new__(cls, p1, p2, **kwargs) + + @property + def xdirection(self): + """The x direction of the ray. + + Positive infinity if the ray points in the positive x direction, + negative infinity if the ray points in the negative x direction, + or 0 if the ray is vertical. + + See Also + ======== + + ydirection + + Examples + ======== + + >>> from sympy import Point, Ray + >>> p1, p2, p3 = Point(0, 0), Point(1, 1), Point(0, -1) + >>> r1, r2 = Ray(p1, p2), Ray(p1, p3) + >>> r1.xdirection + oo + >>> r2.xdirection + 0 + + """ + if self.p1.x < self.p2.x: + return S.Infinity + elif self.p1.x == self.p2.x: + return S.Zero + else: + return S.NegativeInfinity + + @property + def ydirection(self): + """The y direction of the ray. + + Positive infinity if the ray points in the positive y direction, + negative infinity if the ray points in the negative y direction, + or 0 if the ray is horizontal. + + See Also + ======== + + xdirection + + Examples + ======== + + >>> from sympy import Point, Ray + >>> p1, p2, p3 = Point(0, 0), Point(-1, -1), Point(-1, 0) + >>> r1, r2 = Ray(p1, p2), Ray(p1, p3) + >>> r1.ydirection + -oo + >>> r2.ydirection + 0 + + """ + if self.p1.y < self.p2.y: + return S.Infinity + elif self.p1.y == self.p2.y: + return S.Zero + else: + return S.NegativeInfinity + + def closing_angle(r1, r2): + """Return the angle by which r2 must be rotated so it faces the same + direction as r1. + + Parameters + ========== + + r1 : Ray2D + r2 : Ray2D + + Returns + ======= + + angle : angle in radians (ccw angle is positive) + + See Also + ======== + + LinearEntity.angle_between + + Examples + ======== + + >>> from sympy import Ray, pi + >>> r1 = Ray((0, 0), (1, 0)) + >>> r2 = r1.rotate(-pi/2) + >>> angle = r1.closing_angle(r2); angle + pi/2 + >>> r2.rotate(angle).direction.unit == r1.direction.unit + True + >>> r2.closing_angle(r1) + -pi/2 + """ + if not all(isinstance(r, Ray2D) for r in (r1, r2)): + # although the direction property is defined for + # all linear entities, only the Ray is truly a + # directed object + raise TypeError('Both arguments must be Ray2D objects.') + + a1 = atan2(*list(reversed(r1.direction.args))) + a2 = atan2(*list(reversed(r2.direction.args))) + if a1*a2 < 0: + a1 = 2*S.Pi + a1 if a1 < 0 else a1 + a2 = 2*S.Pi + a2 if a2 < 0 else a2 + return a1 - a2 + + +class Segment2D(LinearEntity2D, Segment): + """A line segment in 2D space. + + Parameters + ========== + + p1 : Point + p2 : Point + + Attributes + ========== + + length : number or SymPy expression + midpoint : Point + + See Also + ======== + + sympy.geometry.point.Point, Line + + Examples + ======== + + >>> from sympy import Point, Segment + >>> Segment((1, 0), (1, 1)) # tuples are interpreted as pts + Segment2D(Point2D(1, 0), Point2D(1, 1)) + >>> s = Segment(Point(4, 3), Point(1, 1)); s + Segment2D(Point2D(4, 3), Point2D(1, 1)) + >>> s.points + (Point2D(4, 3), Point2D(1, 1)) + >>> s.slope + 2/3 + >>> s.length + sqrt(13) + >>> s.midpoint + Point2D(5/2, 2) + + """ + def __new__(cls, p1, p2, **kwargs): + p1 = Point(p1, dim=2) + p2 = Point(p2, dim=2) + + if p1 == p2: + return p1 + + return LinearEntity2D.__new__(cls, p1, p2, **kwargs) + + def _svg(self, scale_factor=1., fill_color="#66cc99"): + """Returns SVG path element for the LinearEntity. + + Parameters + ========== + + scale_factor : float + Multiplication factor for the SVG stroke-width. Default is 1. + fill_color : str, optional + Hex string for fill color. Default is "#66cc99". + """ + verts = (N(self.p1), N(self.p2)) + coords = ["{},{}".format(p.x, p.y) for p in verts] + path = "M {} L {}".format(coords[0], " L ".join(coords[1:])) + return ( + '' + ).format(2.*scale_factor, path, fill_color) + + +class LinearEntity3D(LinearEntity): + """An base class for all linear entities (line, ray and segment) + in a 3-dimensional Euclidean space. + + Attributes + ========== + + p1 + p2 + direction_ratio + direction_cosine + points + + Notes + ===== + + This is a base class and is not meant to be instantiated. + """ + def __new__(cls, p1, p2, **kwargs): + p1 = Point3D(p1, dim=3) + p2 = Point3D(p2, dim=3) + if p1 == p2: + # if it makes sense to return a Point, handle in subclass + raise ValueError( + "%s.__new__ requires two unique Points." % cls.__name__) + + return GeometryEntity.__new__(cls, p1, p2, **kwargs) + + ambient_dimension = 3 + + @property + def direction_ratio(self): + """The direction ratio of a given line in 3D. + + See Also + ======== + + sympy.geometry.line.Line3D.equation + + Examples + ======== + + >>> from sympy import Point3D, Line3D + >>> p1, p2 = Point3D(0, 0, 0), Point3D(5, 3, 1) + >>> l = Line3D(p1, p2) + >>> l.direction_ratio + [5, 3, 1] + """ + p1, p2 = self.points + return p1.direction_ratio(p2) + + @property + def direction_cosine(self): + """The normalized direction ratio of a given line in 3D. + + See Also + ======== + + sympy.geometry.line.Line3D.equation + + Examples + ======== + + >>> from sympy import Point3D, Line3D + >>> p1, p2 = Point3D(0, 0, 0), Point3D(5, 3, 1) + >>> l = Line3D(p1, p2) + >>> l.direction_cosine + [sqrt(35)/7, 3*sqrt(35)/35, sqrt(35)/35] + >>> sum(i**2 for i in _) + 1 + """ + p1, p2 = self.points + return p1.direction_cosine(p2) + + +class Line3D(LinearEntity3D, Line): + """An infinite 3D line in space. + + A line is declared with two distinct points or a point and direction_ratio + as defined using keyword `direction_ratio`. + + Parameters + ========== + + p1 : Point3D + pt : Point3D + direction_ratio : list + + See Also + ======== + + sympy.geometry.point.Point3D + sympy.geometry.line.Line + sympy.geometry.line.Line2D + + Examples + ======== + + >>> from sympy import Line3D, Point3D + >>> L = Line3D(Point3D(2, 3, 4), Point3D(3, 5, 1)) + >>> L + Line3D(Point3D(2, 3, 4), Point3D(3, 5, 1)) + >>> L.points + (Point3D(2, 3, 4), Point3D(3, 5, 1)) + """ + def __new__(cls, p1, pt=None, direction_ratio=(), **kwargs): + if isinstance(p1, LinearEntity3D): + if pt is not None: + raise ValueError('if p1 is a LinearEntity, pt must be None.') + p1, pt = p1.args + else: + p1 = Point(p1, dim=3) + if pt is not None and len(direction_ratio) == 0: + pt = Point(pt, dim=3) + elif len(direction_ratio) == 3 and pt is None: + pt = Point3D(p1.x + direction_ratio[0], p1.y + direction_ratio[1], + p1.z + direction_ratio[2]) + else: + raise ValueError('A 2nd Point or keyword "direction_ratio" must ' + 'be used.') + + return LinearEntity3D.__new__(cls, p1, pt, **kwargs) + + def equation(self, x='x', y='y', z='z'): + """Return the equations that define the line in 3D. + + Parameters + ========== + + x : str, optional + The name to use for the x-axis, default value is 'x'. + y : str, optional + The name to use for the y-axis, default value is 'y'. + z : str, optional + The name to use for the z-axis, default value is 'z'. + + Returns + ======= + + equation : Tuple of simultaneous equations + + Examples + ======== + + >>> from sympy import Point3D, Line3D, solve + >>> from sympy.abc import x, y, z + >>> p1, p2 = Point3D(1, 0, 0), Point3D(5, 3, 0) + >>> l1 = Line3D(p1, p2) + >>> eq = l1.equation(x, y, z); eq + (-3*x + 4*y + 3, z) + >>> solve(eq.subs(z, 0), (x, y, z)) + {x: 4*y/3 + 1} + """ + x, y, z, k = [_symbol(i, real=True) for i in (x, y, z, 'k')] + p1, p2 = self.points + d1, d2, d3 = p1.direction_ratio(p2) + x1, y1, z1 = p1 + eqs = [-d1*k + x - x1, -d2*k + y - y1, -d3*k + z - z1] + # eliminate k from equations by solving first eq with k for k + for i, e in enumerate(eqs): + if e.has(k): + kk = solve(e, k)[0] + eqs.pop(i) + break + return Tuple(*[i.subs(k, kk).as_numer_denom()[0] for i in eqs]) + + def distance(self, other): + """ + Finds the shortest distance between a line and another object. + + Parameters + ========== + + Point3D, Line3D, Plane, tuple, list + + Returns + ======= + + distance + + Notes + ===== + + This method accepts only 3D entities as it's parameter + + Tuples and lists are converted to Point3D and therefore must be of + length 3, 2 or 1. + + NotImplementedError is raised if `other` is not an instance of one + of the specified classes: Point3D, Line3D, or Plane. + + Examples + ======== + + >>> from sympy.geometry import Line3D + >>> l1 = Line3D((0, 0, 0), (0, 0, 1)) + >>> l2 = Line3D((0, 1, 0), (1, 1, 1)) + >>> l1.distance(l2) + 1 + + The computed distance may be symbolic, too: + + >>> from sympy.abc import x, y + >>> l1 = Line3D((0, 0, 0), (0, 0, 1)) + >>> l2 = Line3D((0, x, 0), (y, x, 1)) + >>> l1.distance(l2) + Abs(x*y)/Abs(sqrt(y**2)) + + """ + + from .plane import Plane # Avoid circular import + + if isinstance(other, (tuple, list)): + try: + other = Point3D(other) + except ValueError: + pass + + if isinstance(other, Point3D): + return super().distance(other) + + if isinstance(other, Line3D): + if self == other: + return S.Zero + if self.is_parallel(other): + return super().distance(other.p1) + + # Skew lines + self_direction = Matrix(self.direction_ratio) + other_direction = Matrix(other.direction_ratio) + normal = self_direction.cross(other_direction) + plane_through_self = Plane(p1=self.p1, normal_vector=normal) + return other.p1.distance(plane_through_self) + + if isinstance(other, Plane): + return other.distance(self) + + msg = f"{other} has type {type(other)}, which is unsupported" + raise NotImplementedError(msg) + + +class Ray3D(LinearEntity3D, Ray): + """ + A Ray is a semi-line in the space with a source point and a direction. + + Parameters + ========== + + p1 : Point3D + The source of the Ray + p2 : Point or a direction vector + direction_ratio: Determines the direction in which the Ray propagates. + + + Attributes + ========== + + source + xdirection + ydirection + zdirection + + See Also + ======== + + sympy.geometry.point.Point3D, Line3D + + + Examples + ======== + + >>> from sympy import Point3D, Ray3D + >>> r = Ray3D(Point3D(2, 3, 4), Point3D(3, 5, 0)) + >>> r + Ray3D(Point3D(2, 3, 4), Point3D(3, 5, 0)) + >>> r.points + (Point3D(2, 3, 4), Point3D(3, 5, 0)) + >>> r.source + Point3D(2, 3, 4) + >>> r.xdirection + oo + >>> r.ydirection + oo + >>> r.direction_ratio + [1, 2, -4] + + """ + def __new__(cls, p1, pt=None, direction_ratio=(), **kwargs): + if isinstance(p1, LinearEntity3D): + if pt is not None: + raise ValueError('If p1 is a LinearEntity, pt must be None') + p1, pt = p1.args + else: + p1 = Point(p1, dim=3) + if pt is not None and len(direction_ratio) == 0: + pt = Point(pt, dim=3) + elif len(direction_ratio) == 3 and pt is None: + pt = Point3D(p1.x + direction_ratio[0], p1.y + direction_ratio[1], + p1.z + direction_ratio[2]) + else: + raise ValueError(filldedent(''' + A 2nd Point or keyword "direction_ratio" must be used. + ''')) + + return LinearEntity3D.__new__(cls, p1, pt, **kwargs) + + @property + def xdirection(self): + """The x direction of the ray. + + Positive infinity if the ray points in the positive x direction, + negative infinity if the ray points in the negative x direction, + or 0 if the ray is vertical. + + See Also + ======== + + ydirection + + Examples + ======== + + >>> from sympy import Point3D, Ray3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(1, 1, 1), Point3D(0, -1, 0) + >>> r1, r2 = Ray3D(p1, p2), Ray3D(p1, p3) + >>> r1.xdirection + oo + >>> r2.xdirection + 0 + + """ + if self.p1.x < self.p2.x: + return S.Infinity + elif self.p1.x == self.p2.x: + return S.Zero + else: + return S.NegativeInfinity + + @property + def ydirection(self): + """The y direction of the ray. + + Positive infinity if the ray points in the positive y direction, + negative infinity if the ray points in the negative y direction, + or 0 if the ray is horizontal. + + See Also + ======== + + xdirection + + Examples + ======== + + >>> from sympy import Point3D, Ray3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(-1, -1, -1), Point3D(-1, 0, 0) + >>> r1, r2 = Ray3D(p1, p2), Ray3D(p1, p3) + >>> r1.ydirection + -oo + >>> r2.ydirection + 0 + + """ + if self.p1.y < self.p2.y: + return S.Infinity + elif self.p1.y == self.p2.y: + return S.Zero + else: + return S.NegativeInfinity + + @property + def zdirection(self): + """The z direction of the ray. + + Positive infinity if the ray points in the positive z direction, + negative infinity if the ray points in the negative z direction, + or 0 if the ray is horizontal. + + See Also + ======== + + xdirection + + Examples + ======== + + >>> from sympy import Point3D, Ray3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(-1, -1, -1), Point3D(-1, 0, 0) + >>> r1, r2 = Ray3D(p1, p2), Ray3D(p1, p3) + >>> r1.ydirection + -oo + >>> r2.ydirection + 0 + >>> r2.zdirection + 0 + + """ + if self.p1.z < self.p2.z: + return S.Infinity + elif self.p1.z == self.p2.z: + return S.Zero + else: + return S.NegativeInfinity + + +class Segment3D(LinearEntity3D, Segment): + """A line segment in a 3D space. + + Parameters + ========== + + p1 : Point3D + p2 : Point3D + + Attributes + ========== + + length : number or SymPy expression + midpoint : Point3D + + See Also + ======== + + sympy.geometry.point.Point3D, Line3D + + Examples + ======== + + >>> from sympy import Point3D, Segment3D + >>> Segment3D((1, 0, 0), (1, 1, 1)) # tuples are interpreted as pts + Segment3D(Point3D(1, 0, 0), Point3D(1, 1, 1)) + >>> s = Segment3D(Point3D(4, 3, 9), Point3D(1, 1, 7)); s + Segment3D(Point3D(4, 3, 9), Point3D(1, 1, 7)) + >>> s.points + (Point3D(4, 3, 9), Point3D(1, 1, 7)) + >>> s.length + sqrt(17) + >>> s.midpoint + Point3D(5/2, 2, 8) + + """ + def __new__(cls, p1, p2, **kwargs): + p1 = Point(p1, dim=3) + p2 = Point(p2, dim=3) + + if p1 == p2: + return p1 + + return LinearEntity3D.__new__(cls, p1, p2, **kwargs) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/parabola.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/parabola.py new file mode 100644 index 0000000000000000000000000000000000000000..183c593785bb610e6f451a0c87abb2aa34d22494 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/parabola.py @@ -0,0 +1,422 @@ +"""Parabolic geometrical entity. + +Contains +* Parabola + +""" + +from sympy.core import S +from sympy.core.sorting import ordered +from sympy.core.symbol import _symbol, symbols +from sympy.geometry.entity import GeometryEntity, GeometrySet +from sympy.geometry.point import Point, Point2D +from sympy.geometry.line import Line, Line2D, Ray2D, Segment2D, LinearEntity3D +from sympy.geometry.ellipse import Ellipse +from sympy.functions import sign +from sympy.simplify.simplify import simplify +from sympy.solvers.solvers import solve + + +class Parabola(GeometrySet): + """A parabolic GeometryEntity. + + A parabola is declared with a point, that is called 'focus', and + a line, that is called 'directrix'. + Only vertical or horizontal parabolas are currently supported. + + Parameters + ========== + + focus : Point + Default value is Point(0, 0) + directrix : Line + + Attributes + ========== + + focus + directrix + axis of symmetry + focal length + p parameter + vertex + eccentricity + + Raises + ====== + ValueError + When `focus` is not a two dimensional point. + When `focus` is a point of directrix. + NotImplementedError + When `directrix` is neither horizontal nor vertical. + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> p1 = Parabola(Point(0, 0), Line(Point(5, 8), Point(7,8))) + >>> p1.focus + Point2D(0, 0) + >>> p1.directrix + Line2D(Point2D(5, 8), Point2D(7, 8)) + + """ + + def __new__(cls, focus=None, directrix=None, **kwargs): + + if focus: + focus = Point(focus, dim=2) + else: + focus = Point(0, 0) + + directrix = Line(directrix) + + if directrix.contains(focus): + raise ValueError('The focus must not be a point of directrix') + + return GeometryEntity.__new__(cls, focus, directrix, **kwargs) + + @property + def ambient_dimension(self): + """Returns the ambient dimension of parabola. + + Returns + ======= + + ambient_dimension : integer + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> f1 = Point(0, 0) + >>> p1 = Parabola(f1, Line(Point(5, 8), Point(7, 8))) + >>> p1.ambient_dimension + 2 + + """ + return 2 + + @property + def axis_of_symmetry(self): + """Return the axis of symmetry of the parabola: a line + perpendicular to the directrix passing through the focus. + + Returns + ======= + + axis_of_symmetry : Line + + See Also + ======== + + sympy.geometry.line.Line + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> p1 = Parabola(Point(0, 0), Line(Point(5, 8), Point(7, 8))) + >>> p1.axis_of_symmetry + Line2D(Point2D(0, 0), Point2D(0, 1)) + + """ + return self.directrix.perpendicular_line(self.focus) + + @property + def directrix(self): + """The directrix of the parabola. + + Returns + ======= + + directrix : Line + + See Also + ======== + + sympy.geometry.line.Line + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> l1 = Line(Point(5, 8), Point(7, 8)) + >>> p1 = Parabola(Point(0, 0), l1) + >>> p1.directrix + Line2D(Point2D(5, 8), Point2D(7, 8)) + + """ + return self.args[1] + + @property + def eccentricity(self): + """The eccentricity of the parabola. + + Returns + ======= + + eccentricity : number + + A parabola may also be characterized as a conic section with an + eccentricity of 1. As a consequence of this, all parabolas are + similar, meaning that while they can be different sizes, + they are all the same shape. + + See Also + ======== + + https://en.wikipedia.org/wiki/Parabola + + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> p1 = Parabola(Point(0, 0), Line(Point(5, 8), Point(7, 8))) + >>> p1.eccentricity + 1 + + Notes + ----- + The eccentricity for every Parabola is 1 by definition. + + """ + return S.One + + def equation(self, x='x', y='y'): + """The equation of the parabola. + + Parameters + ========== + x : str, optional + Label for the x-axis. Default value is 'x'. + y : str, optional + Label for the y-axis. Default value is 'y'. + + Returns + ======= + equation : SymPy expression + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> p1 = Parabola(Point(0, 0), Line(Point(5, 8), Point(7, 8))) + >>> p1.equation() + -x**2 - 16*y + 64 + >>> p1.equation('f') + -f**2 - 16*y + 64 + >>> p1.equation(y='z') + -x**2 - 16*z + 64 + + """ + x = _symbol(x, real=True) + y = _symbol(y, real=True) + + m = self.directrix.slope + if m is S.Infinity: + t1 = 4 * (self.p_parameter) * (x - self.vertex.x) + t2 = (y - self.vertex.y)**2 + elif m == 0: + t1 = 4 * (self.p_parameter) * (y - self.vertex.y) + t2 = (x - self.vertex.x)**2 + else: + a, b = self.focus + c, d = self.directrix.coefficients[:2] + t1 = (x - a)**2 + (y - b)**2 + t2 = self.directrix.equation(x, y)**2/(c**2 + d**2) + return t1 - t2 + + @property + def focal_length(self): + """The focal length of the parabola. + + Returns + ======= + + focal_lenght : number or symbolic expression + + Notes + ===== + + The distance between the vertex and the focus + (or the vertex and directrix), measured along the axis + of symmetry, is the "focal length". + + See Also + ======== + + https://en.wikipedia.org/wiki/Parabola + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> p1 = Parabola(Point(0, 0), Line(Point(5, 8), Point(7, 8))) + >>> p1.focal_length + 4 + + """ + distance = self.directrix.distance(self.focus) + focal_length = distance/2 + + return focal_length + + @property + def focus(self): + """The focus of the parabola. + + Returns + ======= + + focus : Point + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> f1 = Point(0, 0) + >>> p1 = Parabola(f1, Line(Point(5, 8), Point(7, 8))) + >>> p1.focus + Point2D(0, 0) + + """ + return self.args[0] + + def intersection(self, o): + """The intersection of the parabola and another geometrical entity `o`. + + Parameters + ========== + + o : GeometryEntity, LinearEntity + + Returns + ======= + + intersection : list of GeometryEntity objects + + Examples + ======== + + >>> from sympy import Parabola, Point, Ellipse, Line, Segment + >>> p1 = Point(0,0) + >>> l1 = Line(Point(1, -2), Point(-1,-2)) + >>> parabola1 = Parabola(p1, l1) + >>> parabola1.intersection(Ellipse(Point(0, 0), 2, 5)) + [Point2D(-2, 0), Point2D(2, 0)] + >>> parabola1.intersection(Line(Point(-7, 3), Point(12, 3))) + [Point2D(-4, 3), Point2D(4, 3)] + >>> parabola1.intersection(Segment((-12, -65), (14, -68))) + [] + + """ + x, y = symbols('x y', real=True) + parabola_eq = self.equation() + if isinstance(o, Parabola): + if o in self: + return [o] + else: + return list(ordered([Point(i) for i in solve( + [parabola_eq, o.equation()], [x, y], set=True)[1]])) + elif isinstance(o, Point2D): + if simplify(parabola_eq.subs([(x, o._args[0]), (y, o._args[1])])) == 0: + return [o] + else: + return [] + elif isinstance(o, (Segment2D, Ray2D)): + result = solve([parabola_eq, + Line2D(o.points[0], o.points[1]).equation()], + [x, y], set=True)[1] + return list(ordered([Point2D(i) for i in result if i in o])) + elif isinstance(o, (Line2D, Ellipse)): + return list(ordered([Point2D(i) for i in solve( + [parabola_eq, o.equation()], [x, y], set=True)[1]])) + elif isinstance(o, LinearEntity3D): + raise TypeError('Entity must be two dimensional, not three dimensional') + else: + raise TypeError('Wrong type of argument were put') + + @property + def p_parameter(self): + """P is a parameter of parabola. + + Returns + ======= + + p : number or symbolic expression + + Notes + ===== + + The absolute value of p is the focal length. The sign on p tells + which way the parabola faces. Vertical parabolas that open up + and horizontal that open right, give a positive value for p. + Vertical parabolas that open down and horizontal that open left, + give a negative value for p. + + + See Also + ======== + + https://www.sparknotes.com/math/precalc/conicsections/section2/ + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> p1 = Parabola(Point(0, 0), Line(Point(5, 8), Point(7, 8))) + >>> p1.p_parameter + -4 + + """ + m = self.directrix.slope + if m is S.Infinity: + x = self.directrix.coefficients[2] + p = sign(self.focus.args[0] + x) + elif m == 0: + y = self.directrix.coefficients[2] + p = sign(self.focus.args[1] + y) + else: + d = self.directrix.projection(self.focus) + p = sign(self.focus.x - d.x) + return p * self.focal_length + + @property + def vertex(self): + """The vertex of the parabola. + + Returns + ======= + + vertex : Point + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Parabola, Point, Line + >>> p1 = Parabola(Point(0, 0), Line(Point(5, 8), Point(7, 8))) + >>> p1.vertex + Point2D(0, 4) + + """ + focus = self.focus + m = self.directrix.slope + if m is S.Infinity: + vertex = Point(focus.args[0] - self.p_parameter, focus.args[1]) + elif m == 0: + vertex = Point(focus.args[0], focus.args[1] - self.p_parameter) + else: + vertex = self.axis_of_symmetry.intersection(self)[0] + return vertex diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/plane.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/plane.py new file mode 100644 index 0000000000000000000000000000000000000000..509dc4be5dc41c5df7c33561fdbe5bb0b6620352 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/plane.py @@ -0,0 +1,878 @@ +"""Geometrical Planes. + +Contains +======== +Plane + +""" + +from sympy.core import Dummy, Rational, S, Symbol +from sympy.core.symbol import _symbol +from sympy.functions.elementary.trigonometric import cos, sin, acos, asin, sqrt +from .entity import GeometryEntity +from .line import (Line, Ray, Segment, Line3D, LinearEntity, LinearEntity3D, + Ray3D, Segment3D) +from .point import Point, Point3D +from sympy.matrices import Matrix +from sympy.polys.polytools import cancel +from sympy.solvers import solve, linsolve +from sympy.utilities.iterables import uniq, is_sequence +from sympy.utilities.misc import filldedent, func_name, Undecidable + +from mpmath.libmp.libmpf import prec_to_dps + +import random + + +x, y, z, t = [Dummy('plane_dummy') for i in range(4)] + + +class Plane(GeometryEntity): + """ + A plane is a flat, two-dimensional surface. A plane is the two-dimensional + analogue of a point (zero-dimensions), a line (one-dimension) and a solid + (three-dimensions). A plane can generally be constructed by two types of + inputs. They are: + - three non-collinear points + - a point and the plane's normal vector + + Attributes + ========== + + p1 + normal_vector + + Examples + ======== + + >>> from sympy import Plane, Point3D + >>> Plane(Point3D(1, 1, 1), Point3D(2, 3, 4), Point3D(2, 2, 2)) + Plane(Point3D(1, 1, 1), (-1, 2, -1)) + >>> Plane((1, 1, 1), (2, 3, 4), (2, 2, 2)) + Plane(Point3D(1, 1, 1), (-1, 2, -1)) + >>> Plane(Point3D(1, 1, 1), normal_vector=(1,4,7)) + Plane(Point3D(1, 1, 1), (1, 4, 7)) + + """ + def __new__(cls, p1, a=None, b=None, **kwargs): + p1 = Point3D(p1, dim=3) + if a and b: + p2 = Point(a, dim=3) + p3 = Point(b, dim=3) + if Point3D.are_collinear(p1, p2, p3): + raise ValueError('Enter three non-collinear points') + a = p1.direction_ratio(p2) + b = p1.direction_ratio(p3) + normal_vector = tuple(Matrix(a).cross(Matrix(b))) + else: + a = kwargs.pop('normal_vector', a) + evaluate = kwargs.get('evaluate', True) + if is_sequence(a) and len(a) == 3: + normal_vector = Point3D(a).args if evaluate else a + else: + raise ValueError(filldedent(''' + Either provide 3 3D points or a point with a + normal vector expressed as a sequence of length 3''')) + if all(coord.is_zero for coord in normal_vector): + raise ValueError('Normal vector cannot be zero vector') + return GeometryEntity.__new__(cls, p1, normal_vector, **kwargs) + + def __contains__(self, o): + k = self.equation(x, y, z) + if isinstance(o, (LinearEntity, LinearEntity3D)): + d = Point3D(o.arbitrary_point(t)) + e = k.subs([(x, d.x), (y, d.y), (z, d.z)]) + return e.equals(0) + try: + o = Point(o, dim=3, strict=True) + d = k.xreplace(dict(zip((x, y, z), o.args))) + return d.equals(0) + except TypeError: + return False + + def _eval_evalf(self, prec=15, **options): + pt, tup = self.args + dps = prec_to_dps(prec) + pt = pt.evalf(n=dps, **options) + tup = tuple([i.evalf(n=dps, **options) for i in tup]) + return self.func(pt, normal_vector=tup, evaluate=False) + + def angle_between(self, o): + """Angle between the plane and other geometric entity. + + Parameters + ========== + + LinearEntity3D, Plane. + + Returns + ======= + + angle : angle in radians + + Notes + ===== + + This method accepts only 3D entities as it's parameter, but if you want + to calculate the angle between a 2D entity and a plane you should + first convert to a 3D entity by projecting onto a desired plane and + then proceed to calculate the angle. + + Examples + ======== + + >>> from sympy import Point3D, Line3D, Plane + >>> a = Plane(Point3D(1, 2, 2), normal_vector=(1, 2, 3)) + >>> b = Line3D(Point3D(1, 3, 4), Point3D(2, 2, 2)) + >>> a.angle_between(b) + -asin(sqrt(21)/6) + + """ + if isinstance(o, LinearEntity3D): + a = Matrix(self.normal_vector) + b = Matrix(o.direction_ratio) + c = a.dot(b) + d = sqrt(sum(i**2 for i in self.normal_vector)) + e = sqrt(sum(i**2 for i in o.direction_ratio)) + return asin(c/(d*e)) + if isinstance(o, Plane): + a = Matrix(self.normal_vector) + b = Matrix(o.normal_vector) + c = a.dot(b) + d = sqrt(sum(i**2 for i in self.normal_vector)) + e = sqrt(sum(i**2 for i in o.normal_vector)) + return acos(c/(d*e)) + + + def arbitrary_point(self, u=None, v=None): + """ Returns an arbitrary point on the Plane. If given two + parameters, the point ranges over the entire plane. If given 1 + or no parameters, returns a point with one parameter which, + when varying from 0 to 2*pi, moves the point in a circle of + radius 1 about p1 of the Plane. + + Examples + ======== + + >>> from sympy import Plane, Ray + >>> from sympy.abc import u, v, t, r + >>> p = Plane((1, 1, 1), normal_vector=(1, 0, 0)) + >>> p.arbitrary_point(u, v) + Point3D(1, u + 1, v + 1) + >>> p.arbitrary_point(t) + Point3D(1, cos(t) + 1, sin(t) + 1) + + While arbitrary values of u and v can move the point anywhere in + the plane, the single-parameter point can be used to construct a + ray whose arbitrary point can be located at angle t and radius + r from p.p1: + + >>> Ray(p.p1, _).arbitrary_point(r) + Point3D(1, r*cos(t) + 1, r*sin(t) + 1) + + Returns + ======= + + Point3D + + """ + circle = v is None + if circle: + u = _symbol(u or 't', real=True) + else: + u = _symbol(u or 'u', real=True) + v = _symbol(v or 'v', real=True) + x, y, z = self.normal_vector + a, b, c = self.p1.args + # x1, y1, z1 is a nonzero vector parallel to the plane + if x.is_zero and y.is_zero: + x1, y1, z1 = S.One, S.Zero, S.Zero + else: + x1, y1, z1 = -y, x, S.Zero + # x2, y2, z2 is also parallel to the plane, and orthogonal to x1, y1, z1 + x2, y2, z2 = tuple(Matrix((x, y, z)).cross(Matrix((x1, y1, z1)))) + if circle: + x1, y1, z1 = (w/sqrt(x1**2 + y1**2 + z1**2) for w in (x1, y1, z1)) + x2, y2, z2 = (w/sqrt(x2**2 + y2**2 + z2**2) for w in (x2, y2, z2)) + p = Point3D(a + x1*cos(u) + x2*sin(u), \ + b + y1*cos(u) + y2*sin(u), \ + c + z1*cos(u) + z2*sin(u)) + else: + p = Point3D(a + x1*u + x2*v, b + y1*u + y2*v, c + z1*u + z2*v) + return p + + + @staticmethod + def are_concurrent(*planes): + """Is a sequence of Planes concurrent? + + Two or more Planes are concurrent if their intersections + are a common line. + + Parameters + ========== + + planes: list + + Returns + ======= + + Boolean + + Examples + ======== + + >>> from sympy import Plane, Point3D + >>> a = Plane(Point3D(5, 0, 0), normal_vector=(1, -1, 1)) + >>> b = Plane(Point3D(0, -2, 0), normal_vector=(3, 1, 1)) + >>> c = Plane(Point3D(0, -1, 0), normal_vector=(5, -1, 9)) + >>> Plane.are_concurrent(a, b) + True + >>> Plane.are_concurrent(a, b, c) + False + + """ + planes = list(uniq(planes)) + for i in planes: + if not isinstance(i, Plane): + raise ValueError('All objects should be Planes but got %s' % i.func) + if len(planes) < 2: + return False + planes = list(planes) + first = planes.pop(0) + sol = first.intersection(planes[0]) + if sol == []: + return False + else: + line = sol[0] + for i in planes[1:]: + l = first.intersection(i) + if not l or l[0] not in line: + return False + return True + + + def distance(self, o): + """Distance between the plane and another geometric entity. + + Parameters + ========== + + Point3D, LinearEntity3D, Plane. + + Returns + ======= + + distance + + Notes + ===== + + This method accepts only 3D entities as it's parameter, but if you want + to calculate the distance between a 2D entity and a plane you should + first convert to a 3D entity by projecting onto a desired plane and + then proceed to calculate the distance. + + Examples + ======== + + >>> from sympy import Point3D, Line3D, Plane + >>> a = Plane(Point3D(1, 1, 1), normal_vector=(1, 1, 1)) + >>> b = Point3D(1, 2, 3) + >>> a.distance(b) + sqrt(3) + >>> c = Line3D(Point3D(2, 3, 1), Point3D(1, 2, 2)) + >>> a.distance(c) + 0 + + """ + if self.intersection(o) != []: + return S.Zero + + if isinstance(o, (Segment3D, Ray3D)): + a, b = o.p1, o.p2 + pi, = self.intersection(Line3D(a, b)) + if pi in o: + return self.distance(pi) + elif a in Segment3D(pi, b): + return self.distance(a) + else: + assert isinstance(o, Segment3D) is True + return self.distance(b) + + # following code handles `Point3D`, `LinearEntity3D`, `Plane` + a = o if isinstance(o, Point3D) else o.p1 + n = Point3D(self.normal_vector).unit + d = (a - self.p1).dot(n) + return abs(d) + + + def equals(self, o): + """ + Returns True if self and o are the same mathematical entities. + + Examples + ======== + + >>> from sympy import Plane, Point3D + >>> a = Plane(Point3D(1, 2, 3), normal_vector=(1, 1, 1)) + >>> b = Plane(Point3D(1, 2, 3), normal_vector=(2, 2, 2)) + >>> c = Plane(Point3D(1, 2, 3), normal_vector=(-1, 4, 6)) + >>> a.equals(a) + True + >>> a.equals(b) + True + >>> a.equals(c) + False + """ + if isinstance(o, Plane): + a = self.equation() + b = o.equation() + return cancel(a/b).is_constant() + else: + return False + + + def equation(self, x=None, y=None, z=None): + """The equation of the Plane. + + Examples + ======== + + >>> from sympy import Point3D, Plane + >>> a = Plane(Point3D(1, 1, 2), Point3D(2, 4, 7), Point3D(3, 5, 1)) + >>> a.equation() + -23*x + 11*y - 2*z + 16 + >>> a = Plane(Point3D(1, 4, 2), normal_vector=(6, 6, 6)) + >>> a.equation() + 6*x + 6*y + 6*z - 42 + + """ + x, y, z = [i if i else Symbol(j, real=True) for i, j in zip((x, y, z), 'xyz')] + a = Point3D(x, y, z) + b = self.p1.direction_ratio(a) + c = self.normal_vector + return (sum(i*j for i, j in zip(b, c))) + + + def intersection(self, o): + """ The intersection with other geometrical entity. + + Parameters + ========== + + Point, Point3D, LinearEntity, LinearEntity3D, Plane + + Returns + ======= + + List + + Examples + ======== + + >>> from sympy import Point3D, Line3D, Plane + >>> a = Plane(Point3D(1, 2, 3), normal_vector=(1, 1, 1)) + >>> b = Point3D(1, 2, 3) + >>> a.intersection(b) + [Point3D(1, 2, 3)] + >>> c = Line3D(Point3D(1, 4, 7), Point3D(2, 2, 2)) + >>> a.intersection(c) + [Point3D(2, 2, 2)] + >>> d = Plane(Point3D(6, 0, 0), normal_vector=(2, -5, 3)) + >>> e = Plane(Point3D(2, 0, 0), normal_vector=(3, 4, -3)) + >>> d.intersection(e) + [Line3D(Point3D(78/23, -24/23, 0), Point3D(147/23, 321/23, 23))] + + """ + if not isinstance(o, GeometryEntity): + o = Point(o, dim=3) + if isinstance(o, Point): + if o in self: + return [o] + else: + return [] + if isinstance(o, (LinearEntity, LinearEntity3D)): + # recast to 3D + p1, p2 = o.p1, o.p2 + if isinstance(o, Segment): + o = Segment3D(p1, p2) + elif isinstance(o, Ray): + o = Ray3D(p1, p2) + elif isinstance(o, Line): + o = Line3D(p1, p2) + else: + raise ValueError('unhandled linear entity: %s' % o.func) + if o in self: + return [o] + else: + a = Point3D(o.arbitrary_point(t)) + p1, n = self.p1, Point3D(self.normal_vector) + + # TODO: Replace solve with solveset, when this line is tested + c = solve((a - p1).dot(n), t) + if not c: + return [] + else: + c = [i for i in c if i.is_real is not False] + if len(c) > 1: + c = [i for i in c if i.is_real] + if len(c) != 1: + raise Undecidable("not sure which point is real") + p = a.subs(t, c[0]) + if p not in o: + return [] # e.g. a segment might not intersect a plane + return [p] + if isinstance(o, Plane): + if self.equals(o): + return [self] + if self.is_parallel(o): + return [] + else: + x, y, z = map(Dummy, 'xyz') + a, b = Matrix([self.normal_vector]), Matrix([o.normal_vector]) + c = list(a.cross(b)) + d = self.equation(x, y, z) + e = o.equation(x, y, z) + result = list(linsolve([d, e], x, y, z))[0] + for i in (x, y, z): result = result.subs(i, 0) + return [Line3D(Point3D(result), direction_ratio=c)] + + + def is_coplanar(self, o): + """ Returns True if `o` is coplanar with self, else False. + + Examples + ======== + + >>> from sympy import Plane + >>> o = (0, 0, 0) + >>> p = Plane(o, (1, 1, 1)) + >>> p2 = Plane(o, (2, 2, 2)) + >>> p == p2 + False + >>> p.is_coplanar(p2) + True + """ + if isinstance(o, Plane): + return not cancel(self.equation(x, y, z)/o.equation(x, y, z)).has(x, y, z) + if isinstance(o, Point3D): + return o in self + elif isinstance(o, LinearEntity3D): + return all(i in self for i in self) + elif isinstance(o, GeometryEntity): # XXX should only be handling 2D objects now + return all(i == 0 for i in self.normal_vector[:2]) + + + def is_parallel(self, l): + """Is the given geometric entity parallel to the plane? + + Parameters + ========== + + LinearEntity3D or Plane + + Returns + ======= + + Boolean + + Examples + ======== + + >>> from sympy import Plane, Point3D + >>> a = Plane(Point3D(1,4,6), normal_vector=(2, 4, 6)) + >>> b = Plane(Point3D(3,1,3), normal_vector=(4, 8, 12)) + >>> a.is_parallel(b) + True + + """ + if isinstance(l, LinearEntity3D): + a = l.direction_ratio + b = self.normal_vector + return sum(i*j for i, j in zip(a, b)) == 0 + if isinstance(l, Plane): + a = Matrix(l.normal_vector) + b = Matrix(self.normal_vector) + return bool(a.cross(b).is_zero_matrix) + + + def is_perpendicular(self, l): + """Is the given geometric entity perpendicualar to the given plane? + + Parameters + ========== + + LinearEntity3D or Plane + + Returns + ======= + + Boolean + + Examples + ======== + + >>> from sympy import Plane, Point3D + >>> a = Plane(Point3D(1,4,6), normal_vector=(2, 4, 6)) + >>> b = Plane(Point3D(2, 2, 2), normal_vector=(-1, 2, -1)) + >>> a.is_perpendicular(b) + True + + """ + if isinstance(l, LinearEntity3D): + a = Matrix(l.direction_ratio) + b = Matrix(self.normal_vector) + if a.cross(b).is_zero_matrix: + return True + else: + return False + elif isinstance(l, Plane): + a = Matrix(l.normal_vector) + b = Matrix(self.normal_vector) + if a.dot(b) == 0: + return True + else: + return False + else: + return False + + @property + def normal_vector(self): + """Normal vector of the given plane. + + Examples + ======== + + >>> from sympy import Point3D, Plane + >>> a = Plane(Point3D(1, 1, 1), Point3D(2, 3, 4), Point3D(2, 2, 2)) + >>> a.normal_vector + (-1, 2, -1) + >>> a = Plane(Point3D(1, 1, 1), normal_vector=(1, 4, 7)) + >>> a.normal_vector + (1, 4, 7) + + """ + return self.args[1] + + @property + def p1(self): + """The only defining point of the plane. Others can be obtained from the + arbitrary_point method. + + See Also + ======== + + sympy.geometry.point.Point3D + + Examples + ======== + + >>> from sympy import Point3D, Plane + >>> a = Plane(Point3D(1, 1, 1), Point3D(2, 3, 4), Point3D(2, 2, 2)) + >>> a.p1 + Point3D(1, 1, 1) + + """ + return self.args[0] + + def parallel_plane(self, pt): + """ + Plane parallel to the given plane and passing through the point pt. + + Parameters + ========== + + pt: Point3D + + Returns + ======= + + Plane + + Examples + ======== + + >>> from sympy import Plane, Point3D + >>> a = Plane(Point3D(1, 4, 6), normal_vector=(2, 4, 6)) + >>> a.parallel_plane(Point3D(2, 3, 5)) + Plane(Point3D(2, 3, 5), (2, 4, 6)) + + """ + a = self.normal_vector + return Plane(pt, normal_vector=a) + + def perpendicular_line(self, pt): + """A line perpendicular to the given plane. + + Parameters + ========== + + pt: Point3D + + Returns + ======= + + Line3D + + Examples + ======== + + >>> from sympy import Plane, Point3D + >>> a = Plane(Point3D(1,4,6), normal_vector=(2, 4, 6)) + >>> a.perpendicular_line(Point3D(9, 8, 7)) + Line3D(Point3D(9, 8, 7), Point3D(11, 12, 13)) + + """ + a = self.normal_vector + return Line3D(pt, direction_ratio=a) + + def perpendicular_plane(self, *pts): + """ + Return a perpendicular passing through the given points. If the + direction ratio between the points is the same as the Plane's normal + vector then, to select from the infinite number of possible planes, + a third point will be chosen on the z-axis (or the y-axis + if the normal vector is already parallel to the z-axis). If less than + two points are given they will be supplied as follows: if no point is + given then pt1 will be self.p1; if a second point is not given it will + be a point through pt1 on a line parallel to the z-axis (if the normal + is not already the z-axis, otherwise on the line parallel to the + y-axis). + + Parameters + ========== + + pts: 0, 1 or 2 Point3D + + Returns + ======= + + Plane + + Examples + ======== + + >>> from sympy import Plane, Point3D + >>> a, b = Point3D(0, 0, 0), Point3D(0, 1, 0) + >>> Z = (0, 0, 1) + >>> p = Plane(a, normal_vector=Z) + >>> p.perpendicular_plane(a, b) + Plane(Point3D(0, 0, 0), (1, 0, 0)) + """ + if len(pts) > 2: + raise ValueError('No more than 2 pts should be provided.') + + pts = list(pts) + if len(pts) == 0: + pts.append(self.p1) + if len(pts) == 1: + x, y, z = self.normal_vector + if x == y == 0: + dir = (0, 1, 0) + else: + dir = (0, 0, 1) + pts.append(pts[0] + Point3D(*dir)) + + p1, p2 = [Point(i, dim=3) for i in pts] + l = Line3D(p1, p2) + n = Line3D(p1, direction_ratio=self.normal_vector) + if l in n: # XXX should an error be raised instead? + # there are infinitely many perpendicular planes; + x, y, z = self.normal_vector + if x == y == 0: + # the z axis is the normal so pick a pt on the y-axis + p3 = Point3D(0, 1, 0) # case 1 + else: + # else pick a pt on the z axis + p3 = Point3D(0, 0, 1) # case 2 + # in case that point is already given, move it a bit + if p3 in l: + p3 *= 2 # case 3 + else: + p3 = p1 + Point3D(*self.normal_vector) # case 4 + return Plane(p1, p2, p3) + + def projection_line(self, line): + """Project the given line onto the plane through the normal plane + containing the line. + + Parameters + ========== + + LinearEntity or LinearEntity3D + + Returns + ======= + + Point3D, Line3D, Ray3D or Segment3D + + Notes + ===== + + For the interaction between 2D and 3D lines(segments, rays), you should + convert the line to 3D by using this method. For example for finding the + intersection between a 2D and a 3D line, convert the 2D line to a 3D line + by projecting it on a required plane and then proceed to find the + intersection between those lines. + + Examples + ======== + + >>> from sympy import Plane, Line, Line3D, Point3D + >>> a = Plane(Point3D(1, 1, 1), normal_vector=(1, 1, 1)) + >>> b = Line(Point3D(1, 1), Point3D(2, 2)) + >>> a.projection_line(b) + Line3D(Point3D(4/3, 4/3, 1/3), Point3D(5/3, 5/3, -1/3)) + >>> c = Line3D(Point3D(1, 1, 1), Point3D(2, 2, 2)) + >>> a.projection_line(c) + Point3D(1, 1, 1) + + """ + if not isinstance(line, (LinearEntity, LinearEntity3D)): + raise NotImplementedError('Enter a linear entity only') + a, b = self.projection(line.p1), self.projection(line.p2) + if a == b: + # projection does not imply intersection so for + # this case (line parallel to plane's normal) we + # return the projection point + return a + if isinstance(line, (Line, Line3D)): + return Line3D(a, b) + if isinstance(line, (Ray, Ray3D)): + return Ray3D(a, b) + if isinstance(line, (Segment, Segment3D)): + return Segment3D(a, b) + + def projection(self, pt): + """Project the given point onto the plane along the plane normal. + + Parameters + ========== + + Point or Point3D + + Returns + ======= + + Point3D + + Examples + ======== + + >>> from sympy import Plane, Point3D + >>> A = Plane(Point3D(1, 1, 2), normal_vector=(1, 1, 1)) + + The projection is along the normal vector direction, not the z + axis, so (1, 1) does not project to (1, 1, 2) on the plane A: + + >>> b = Point3D(1, 1) + >>> A.projection(b) + Point3D(5/3, 5/3, 2/3) + >>> _ in A + True + + But the point (1, 1, 2) projects to (1, 1) on the XY-plane: + + >>> XY = Plane((0, 0, 0), (0, 0, 1)) + >>> XY.projection((1, 1, 2)) + Point3D(1, 1, 0) + """ + rv = Point(pt, dim=3) + if rv in self: + return rv + return self.intersection(Line3D(rv, rv + Point3D(self.normal_vector)))[0] + + def random_point(self, seed=None): + """ Returns a random point on the Plane. + + Returns + ======= + + Point3D + + Examples + ======== + + >>> from sympy import Plane + >>> p = Plane((1, 0, 0), normal_vector=(0, 1, 0)) + >>> r = p.random_point(seed=42) # seed value is optional + >>> r.n(3) + Point3D(2.29, 0, -1.35) + + The random point can be moved to lie on the circle of radius + 1 centered on p1: + + >>> c = p.p1 + (r - p.p1).unit + >>> c.distance(p.p1).equals(1) + True + """ + if seed is not None: + rng = random.Random(seed) + else: + rng = random + params = { + x: 2*Rational(rng.gauss(0, 1)) - 1, + y: 2*Rational(rng.gauss(0, 1)) - 1} + return self.arbitrary_point(x, y).subs(params) + + def parameter_value(self, other, u, v=None): + """Return the parameter(s) corresponding to the given point. + + Examples + ======== + + >>> from sympy import pi, Plane + >>> from sympy.abc import t, u, v + >>> p = Plane((2, 0, 0), (0, 0, 1), (0, 1, 0)) + + By default, the parameter value returned defines a point + that is a distance of 1 from the Plane's p1 value and + in line with the given point: + + >>> on_circle = p.arbitrary_point(t).subs(t, pi/4) + >>> on_circle.distance(p.p1) + 1 + >>> p.parameter_value(on_circle, t) + {t: pi/4} + + Moving the point twice as far from p1 does not change + the parameter value: + + >>> off_circle = p.p1 + (on_circle - p.p1)*2 + >>> off_circle.distance(p.p1) + 2 + >>> p.parameter_value(off_circle, t) + {t: pi/4} + + If the 2-value parameter is desired, supply the two + parameter symbols and a replacement dictionary will + be returned: + + >>> p.parameter_value(on_circle, u, v) + {u: sqrt(10)/10, v: sqrt(10)/30} + >>> p.parameter_value(off_circle, u, v) + {u: sqrt(10)/5, v: sqrt(10)/15} + """ + if not isinstance(other, GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if not isinstance(other, Point): + raise ValueError("other must be a point") + if other == self.p1: + return other + if isinstance(u, Symbol) and v is None: + delta = self.arbitrary_point(u) - self.p1 + eq = delta - (other - self.p1).unit + sol = solve(eq, u, dict=True) + elif isinstance(u, Symbol) and isinstance(v, Symbol): + pt = self.arbitrary_point(u, v) + sol = solve(pt - other, (u, v), dict=True) + else: + raise ValueError('expecting 1 or 2 symbols') + if not sol: + raise ValueError("Given point is not on %s" % func_name(self)) + return sol[0] # {t: tval} or {u: uval, v: vval} + + @property + def ambient_dimension(self): + return self.p1.ambient_dimension diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/point.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/point.py new file mode 100644 index 0000000000000000000000000000000000000000..19e6c566f06de4df086912470dc35d0f4af3bd38 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/point.py @@ -0,0 +1,1378 @@ +"""Geometrical Points. + +Contains +======== +Point +Point2D +Point3D + +When methods of Point require 1 or more points as arguments, they +can be passed as a sequence of coordinates or Points: + +>>> from sympy import Point +>>> Point(1, 1).is_collinear((2, 2), (3, 4)) +False +>>> Point(1, 1).is_collinear(Point(2, 2), Point(3, 4)) +False + +""" + +import warnings + +from sympy.core import S, sympify, Expr +from sympy.core.add import Add +from sympy.core.containers import Tuple +from sympy.core.numbers import Float +from sympy.core.parameters import global_parameters +from sympy.simplify.simplify import nsimplify, simplify +from sympy.geometry.exceptions import GeometryError +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.complexes import im +from sympy.functions.elementary.trigonometric import cos, sin +from sympy.matrices import Matrix +from sympy.matrices.expressions import Transpose +from sympy.utilities.iterables import uniq, is_sequence +from sympy.utilities.misc import filldedent, func_name, Undecidable + +from .entity import GeometryEntity + +from mpmath.libmp.libmpf import prec_to_dps + + +class Point(GeometryEntity): + """A point in a n-dimensional Euclidean space. + + Parameters + ========== + + coords : sequence of n-coordinate values. In the special + case where n=2 or 3, a Point2D or Point3D will be created + as appropriate. + evaluate : if `True` (default), all floats are turn into + exact types. + dim : number of coordinates the point should have. If coordinates + are unspecified, they are padded with zeros. + on_morph : indicates what should happen when the number of + coordinates of a point need to be changed by adding or + removing zeros. Possible values are `'warn'`, `'error'`, or + `ignore` (default). No warning or error is given when `*args` + is empty and `dim` is given. An error is always raised when + trying to remove nonzero coordinates. + + + Attributes + ========== + + length + origin: A `Point` representing the origin of the + appropriately-dimensioned space. + + Raises + ====== + + TypeError : When instantiating with anything but a Point or sequence + ValueError : when instantiating with a sequence with length < 2 or + when trying to reduce dimensions if keyword `on_morph='error'` is + set. + + See Also + ======== + + sympy.geometry.line.Segment : Connects two Points + + Examples + ======== + + >>> from sympy import Point + >>> from sympy.abc import x + >>> Point(1, 2, 3) + Point3D(1, 2, 3) + >>> Point([1, 2]) + Point2D(1, 2) + >>> Point(0, x) + Point2D(0, x) + >>> Point(dim=4) + Point(0, 0, 0, 0) + + Floats are automatically converted to Rational unless the + evaluate flag is False: + + >>> Point(0.5, 0.25) + Point2D(1/2, 1/4) + >>> Point(0.5, 0.25, evaluate=False) + Point2D(0.5, 0.25) + + """ + + is_Point = True + + def __new__(cls, *args, **kwargs): + evaluate = kwargs.get('evaluate', global_parameters.evaluate) + on_morph = kwargs.get('on_morph', 'ignore') + + # unpack into coords + coords = args[0] if len(args) == 1 else args + + # check args and handle quickly handle Point instances + if isinstance(coords, Point): + # even if we're mutating the dimension of a point, we + # don't reevaluate its coordinates + evaluate = False + if len(coords) == kwargs.get('dim', len(coords)): + return coords + + if not is_sequence(coords): + raise TypeError(filldedent(''' + Expecting sequence of coordinates, not `{}`''' + .format(func_name(coords)))) + # A point where only `dim` is specified is initialized + # to zeros. + if len(coords) == 0 and kwargs.get('dim', None): + coords = (S.Zero,)*kwargs.get('dim') + + coords = Tuple(*coords) + dim = kwargs.get('dim', len(coords)) + + if len(coords) < 2: + raise ValueError(filldedent(''' + Point requires 2 or more coordinates or + keyword `dim` > 1.''')) + if len(coords) != dim: + message = ("Dimension of {} needs to be changed " + "from {} to {}.").format(coords, len(coords), dim) + if on_morph == 'ignore': + pass + elif on_morph == "error": + raise ValueError(message) + elif on_morph == 'warn': + warnings.warn(message, stacklevel=2) + else: + raise ValueError(filldedent(''' + on_morph value should be 'error', + 'warn' or 'ignore'.''')) + if any(coords[dim:]): + raise ValueError('Nonzero coordinates cannot be removed.') + if any(a.is_number and im(a).is_zero is False for a in coords): + raise ValueError('Imaginary coordinates are not permitted.') + if not all(isinstance(a, Expr) for a in coords): + raise TypeError('Coordinates must be valid SymPy expressions.') + + # pad with zeros appropriately + coords = coords[:dim] + (S.Zero,)*(dim - len(coords)) + + # Turn any Floats into rationals and simplify + # any expressions before we instantiate + if evaluate: + coords = coords.xreplace({ + f: simplify(nsimplify(f, rational=True)) + for f in coords.atoms(Float)}) + + # return 2D or 3D instances + if len(coords) == 2: + kwargs['_nocheck'] = True + return Point2D(*coords, **kwargs) + elif len(coords) == 3: + kwargs['_nocheck'] = True + return Point3D(*coords, **kwargs) + + # the general Point + return GeometryEntity.__new__(cls, *coords) + + def __abs__(self): + """Returns the distance between this point and the origin.""" + origin = Point([0]*len(self)) + return Point.distance(origin, self) + + def __add__(self, other): + """Add other to self by incrementing self's coordinates by + those of other. + + Notes + ===== + + >>> from sympy import Point + + When sequences of coordinates are passed to Point methods, they + are converted to a Point internally. This __add__ method does + not do that so if floating point values are used, a floating + point result (in terms of SymPy Floats) will be returned. + + >>> Point(1, 2) + (.1, .2) + Point2D(1.1, 2.2) + + If this is not desired, the `translate` method can be used or + another Point can be added: + + >>> Point(1, 2).translate(.1, .2) + Point2D(11/10, 11/5) + >>> Point(1, 2) + Point(.1, .2) + Point2D(11/10, 11/5) + + See Also + ======== + + sympy.geometry.point.Point.translate + + """ + try: + s, o = Point._normalize_dimension(self, Point(other, evaluate=False)) + except TypeError: + raise GeometryError("Don't know how to add {} and a Point object".format(other)) + + coords = [simplify(a + b) for a, b in zip(s, o)] + return Point(coords, evaluate=False) + + def __contains__(self, item): + return item in self.args + + def __truediv__(self, divisor): + """Divide point's coordinates by a factor.""" + divisor = sympify(divisor) + coords = [simplify(x/divisor) for x in self.args] + return Point(coords, evaluate=False) + + def __eq__(self, other): + if not isinstance(other, Point) or len(self.args) != len(other.args): + return False + return self.args == other.args + + def __getitem__(self, key): + return self.args[key] + + def __hash__(self): + return hash(self.args) + + def __iter__(self): + return self.args.__iter__() + + def __len__(self): + return len(self.args) + + def __mul__(self, factor): + """Multiply point's coordinates by a factor. + + Notes + ===== + + >>> from sympy import Point + + When multiplying a Point by a floating point number, + the coordinates of the Point will be changed to Floats: + + >>> Point(1, 2)*0.1 + Point2D(0.1, 0.2) + + If this is not desired, the `scale` method can be used or + else only multiply or divide by integers: + + >>> Point(1, 2).scale(1.1, 1.1) + Point2D(11/10, 11/5) + >>> Point(1, 2)*11/10 + Point2D(11/10, 11/5) + + See Also + ======== + + sympy.geometry.point.Point.scale + """ + factor = sympify(factor) + coords = [simplify(x*factor) for x in self.args] + return Point(coords, evaluate=False) + + def __rmul__(self, factor): + """Multiply a factor by point's coordinates.""" + return self.__mul__(factor) + + def __neg__(self): + """Negate the point.""" + coords = [-x for x in self.args] + return Point(coords, evaluate=False) + + def __sub__(self, other): + """Subtract two points, or subtract a factor from this point's + coordinates.""" + return self + [-x for x in other] + + @classmethod + def _normalize_dimension(cls, *points, **kwargs): + """Ensure that points have the same dimension. + By default `on_morph='warn'` is passed to the + `Point` constructor.""" + # if we have a built-in ambient dimension, use it + dim = getattr(cls, '_ambient_dimension', None) + # override if we specified it + dim = kwargs.get('dim', dim) + # if no dim was given, use the highest dimensional point + if dim is None: + dim = max(i.ambient_dimension for i in points) + if all(i.ambient_dimension == dim for i in points): + return list(points) + kwargs['dim'] = dim + kwargs['on_morph'] = kwargs.get('on_morph', 'warn') + return [Point(i, **kwargs) for i in points] + + @staticmethod + def affine_rank(*args): + """The affine rank of a set of points is the dimension + of the smallest affine space containing all the points. + For example, if the points lie on a line (and are not all + the same) their affine rank is 1. If the points lie on a plane + but not a line, their affine rank is 2. By convention, the empty + set has affine rank -1.""" + + if len(args) == 0: + return -1 + # make sure we're genuinely points + # and translate every point to the origin + points = Point._normalize_dimension(*[Point(i) for i in args]) + origin = points[0] + points = [i - origin for i in points[1:]] + + m = Matrix([i.args for i in points]) + # XXX fragile -- what is a better way? + return m.rank(iszerofunc = lambda x: + abs(x.n(2)) < 1e-12 if x.is_number else x.is_zero) + + @property + def ambient_dimension(self): + """Number of components this point has.""" + return getattr(self, '_ambient_dimension', len(self)) + + @classmethod + def are_coplanar(cls, *points): + """Return True if there exists a plane in which all the points + lie. A trivial True value is returned if `len(points) < 3` or + all Points are 2-dimensional. + + Parameters + ========== + + A set of points + + Raises + ====== + + ValueError : if less than 3 unique points are given + + Returns + ======= + + boolean + + Examples + ======== + + >>> from sympy import Point3D + >>> p1 = Point3D(1, 2, 2) + >>> p2 = Point3D(2, 7, 2) + >>> p3 = Point3D(0, 0, 2) + >>> p4 = Point3D(1, 1, 2) + >>> Point3D.are_coplanar(p1, p2, p3, p4) + True + >>> p5 = Point3D(0, 1, 3) + >>> Point3D.are_coplanar(p1, p2, p3, p5) + False + + """ + if len(points) <= 1: + return True + + points = cls._normalize_dimension(*[Point(i) for i in points]) + # quick exit if we are in 2D + if points[0].ambient_dimension == 2: + return True + points = list(uniq(points)) + return Point.affine_rank(*points) <= 2 + + def distance(self, other): + """The Euclidean distance between self and another GeometricEntity. + + Returns + ======= + + distance : number or symbolic expression. + + Raises + ====== + + TypeError : if other is not recognized as a GeometricEntity or is a + GeometricEntity for which distance is not defined. + + See Also + ======== + + sympy.geometry.line.Segment.length + sympy.geometry.point.Point.taxicab_distance + + Examples + ======== + + >>> from sympy import Point, Line + >>> p1, p2 = Point(1, 1), Point(4, 5) + >>> l = Line((3, 1), (2, 2)) + >>> p1.distance(p2) + 5 + >>> p1.distance(l) + sqrt(2) + + The computed distance may be symbolic, too: + + >>> from sympy.abc import x, y + >>> p3 = Point(x, y) + >>> p3.distance((0, 0)) + sqrt(x**2 + y**2) + + """ + if not isinstance(other, GeometryEntity): + try: + other = Point(other, dim=self.ambient_dimension) + except TypeError: + raise TypeError("not recognized as a GeometricEntity: %s" % type(other)) + if isinstance(other, Point): + s, p = Point._normalize_dimension(self, Point(other)) + return sqrt(Add(*((a - b)**2 for a, b in zip(s, p)))) + distance = getattr(other, 'distance', None) + if distance is None: + raise TypeError("distance between Point and %s is not defined" % type(other)) + return distance(self) + + def dot(self, p): + """Return dot product of self with another Point.""" + if not is_sequence(p): + p = Point(p) # raise the error via Point + return Add(*(a*b for a, b in zip(self, p))) + + def equals(self, other): + """Returns whether the coordinates of self and other agree.""" + # a point is equal to another point if all its components are equal + if not isinstance(other, Point) or len(self) != len(other): + return False + return all(a.equals(b) for a, b in zip(self, other)) + + def _eval_evalf(self, prec=15, **options): + """Evaluate the coordinates of the point. + + This method will, where possible, create and return a new Point + where the coordinates are evaluated as floating point numbers to + the precision indicated (default=15). + + Parameters + ========== + + prec : int + + Returns + ======= + + point : Point + + Examples + ======== + + >>> from sympy import Point, Rational + >>> p1 = Point(Rational(1, 2), Rational(3, 2)) + >>> p1 + Point2D(1/2, 3/2) + >>> p1.evalf() + Point2D(0.5, 1.5) + + """ + dps = prec_to_dps(prec) + coords = [x.evalf(n=dps, **options) for x in self.args] + return Point(*coords, evaluate=False) + + def intersection(self, other): + """The intersection between this point and another GeometryEntity. + + Parameters + ========== + + other : GeometryEntity or sequence of coordinates + + Returns + ======= + + intersection : list of Points + + Notes + ===== + + The return value will either be an empty list if there is no + intersection, otherwise it will contain this point. + + Examples + ======== + + >>> from sympy import Point + >>> p1, p2, p3 = Point(0, 0), Point(1, 1), Point(0, 0) + >>> p1.intersection(p2) + [] + >>> p1.intersection(p3) + [Point2D(0, 0)] + + """ + if not isinstance(other, GeometryEntity): + other = Point(other) + if isinstance(other, Point): + if self == other: + return [self] + p1, p2 = Point._normalize_dimension(self, other) + if p1 == self and p1 == p2: + return [self] + return [] + return other.intersection(self) + + def is_collinear(self, *args): + """Returns `True` if there exists a line + that contains `self` and `points`. Returns `False` otherwise. + A trivially True value is returned if no points are given. + + Parameters + ========== + + args : sequence of Points + + Returns + ======= + + is_collinear : boolean + + See Also + ======== + + sympy.geometry.line.Line + + Examples + ======== + + >>> from sympy import Point + >>> from sympy.abc import x + >>> p1, p2 = Point(0, 0), Point(1, 1) + >>> p3, p4, p5 = Point(2, 2), Point(x, x), Point(1, 2) + >>> Point.is_collinear(p1, p2, p3, p4) + True + >>> Point.is_collinear(p1, p2, p3, p5) + False + + """ + points = (self,) + args + points = Point._normalize_dimension(*[Point(i) for i in points]) + points = list(uniq(points)) + return Point.affine_rank(*points) <= 1 + + def is_concyclic(self, *args): + """Do `self` and the given sequence of points lie in a circle? + + Returns True if the set of points are concyclic and + False otherwise. A trivial value of True is returned + if there are fewer than 2 other points. + + Parameters + ========== + + args : sequence of Points + + Returns + ======= + + is_concyclic : boolean + + + Examples + ======== + + >>> from sympy import Point + + Define 4 points that are on the unit circle: + + >>> p1, p2, p3, p4 = Point(1, 0), (0, 1), (-1, 0), (0, -1) + + >>> p1.is_concyclic() == p1.is_concyclic(p2, p3, p4) == True + True + + Define a point not on that circle: + + >>> p = Point(1, 1) + + >>> p.is_concyclic(p1, p2, p3) + False + + """ + points = (self,) + args + points = Point._normalize_dimension(*[Point(i) for i in points]) + points = list(uniq(points)) + if not Point.affine_rank(*points) <= 2: + return False + origin = points[0] + points = [p - origin for p in points] + # points are concyclic if they are coplanar and + # there is a point c so that ||p_i-c|| == ||p_j-c|| for all + # i and j. Rearranging this equation gives us the following + # condition: the matrix `mat` must not a pivot in the last + # column. + mat = Matrix([list(i) + [i.dot(i)] for i in points]) + rref, pivots = mat.rref() + if len(origin) not in pivots: + return True + return False + + @property + def is_nonzero(self): + """True if any coordinate is nonzero, False if every coordinate is zero, + and None if it cannot be determined.""" + is_zero = self.is_zero + if is_zero is None: + return None + return not is_zero + + def is_scalar_multiple(self, p): + """Returns whether each coordinate of `self` is a scalar + multiple of the corresponding coordinate in point p. + """ + s, o = Point._normalize_dimension(self, Point(p)) + # 2d points happen a lot, so optimize this function call + if s.ambient_dimension == 2: + (x1, y1), (x2, y2) = s.args, o.args + rv = (x1*y2 - x2*y1).equals(0) + if rv is None: + raise Undecidable(filldedent( + '''Cannot determine if %s is a scalar multiple of + %s''' % (s, o))) + + # if the vectors p1 and p2 are linearly dependent, then they must + # be scalar multiples of each other + m = Matrix([s.args, o.args]) + return m.rank() < 2 + + @property + def is_zero(self): + """True if every coordinate is zero, False if any coordinate is not zero, + and None if it cannot be determined.""" + nonzero = [x.is_nonzero for x in self.args] + if any(nonzero): + return False + if any(x is None for x in nonzero): + return None + return True + + @property + def length(self): + """ + Treating a Point as a Line, this returns 0 for the length of a Point. + + Examples + ======== + + >>> from sympy import Point + >>> p = Point(0, 1) + >>> p.length + 0 + """ + return S.Zero + + def midpoint(self, p): + """The midpoint between self and point p. + + Parameters + ========== + + p : Point + + Returns + ======= + + midpoint : Point + + See Also + ======== + + sympy.geometry.line.Segment.midpoint + + Examples + ======== + + >>> from sympy import Point + >>> p1, p2 = Point(1, 1), Point(13, 5) + >>> p1.midpoint(p2) + Point2D(7, 3) + + """ + s, p = Point._normalize_dimension(self, Point(p)) + return Point([simplify((a + b)*S.Half) for a, b in zip(s, p)]) + + @property + def origin(self): + """A point of all zeros of the same ambient dimension + as the current point""" + return Point([0]*len(self), evaluate=False) + + @property + def orthogonal_direction(self): + """Returns a non-zero point that is orthogonal to the + line containing `self` and the origin. + + Examples + ======== + + >>> from sympy import Line, Point + >>> a = Point(1, 2, 3) + >>> a.orthogonal_direction + Point3D(-2, 1, 0) + >>> b = _ + >>> Line(b, b.origin).is_perpendicular(Line(a, a.origin)) + True + """ + dim = self.ambient_dimension + # if a coordinate is zero, we can put a 1 there and zeros elsewhere + if self[0].is_zero: + return Point([1] + (dim - 1)*[0]) + if self[1].is_zero: + return Point([0,1] + (dim - 2)*[0]) + # if the first two coordinates aren't zero, we can create a non-zero + # orthogonal vector by swapping them, negating one, and padding with zeros + return Point([-self[1], self[0]] + (dim - 2)*[0]) + + @staticmethod + def project(a, b): + """Project the point `a` onto the line between the origin + and point `b` along the normal direction. + + Parameters + ========== + + a : Point + b : Point + + Returns + ======= + + p : Point + + See Also + ======== + + sympy.geometry.line.LinearEntity.projection + + Examples + ======== + + >>> from sympy import Line, Point + >>> a = Point(1, 2) + >>> b = Point(2, 5) + >>> z = a.origin + >>> p = Point.project(a, b) + >>> Line(p, a).is_perpendicular(Line(p, b)) + True + >>> Point.is_collinear(z, p, b) + True + """ + a, b = Point._normalize_dimension(Point(a), Point(b)) + if b.is_zero: + raise ValueError("Cannot project to the zero vector.") + return b*(a.dot(b) / b.dot(b)) + + def taxicab_distance(self, p): + """The Taxicab Distance from self to point p. + + Returns the sum of the horizontal and vertical distances to point p. + + Parameters + ========== + + p : Point + + Returns + ======= + + taxicab_distance : The sum of the horizontal + and vertical distances to point p. + + See Also + ======== + + sympy.geometry.point.Point.distance + + Examples + ======== + + >>> from sympy import Point + >>> p1, p2 = Point(1, 1), Point(4, 5) + >>> p1.taxicab_distance(p2) + 7 + + """ + s, p = Point._normalize_dimension(self, Point(p)) + return Add(*(abs(a - b) for a, b in zip(s, p))) + + def canberra_distance(self, p): + """The Canberra Distance from self to point p. + + Returns the weighted sum of horizontal and vertical distances to + point p. + + Parameters + ========== + + p : Point + + Returns + ======= + + canberra_distance : The weighted sum of horizontal and vertical + distances to point p. The weight used is the sum of absolute values + of the coordinates. + + Examples + ======== + + >>> from sympy import Point + >>> p1, p2 = Point(1, 1), Point(3, 3) + >>> p1.canberra_distance(p2) + 1 + >>> p1, p2 = Point(0, 0), Point(3, 3) + >>> p1.canberra_distance(p2) + 2 + + Raises + ====== + + ValueError when both vectors are zero. + + See Also + ======== + + sympy.geometry.point.Point.distance + + """ + + s, p = Point._normalize_dimension(self, Point(p)) + if self.is_zero and p.is_zero: + raise ValueError("Cannot project to the zero vector.") + return Add(*((abs(a - b)/(abs(a) + abs(b))) for a, b in zip(s, p))) + + @property + def unit(self): + """Return the Point that is in the same direction as `self` + and a distance of 1 from the origin""" + return self / abs(self) + + +class Point2D(Point): + """A point in a 2-dimensional Euclidean space. + + Parameters + ========== + + coords + A sequence of 2 coordinate values. + + Attributes + ========== + + x + y + length + + Raises + ====== + + TypeError + When trying to add or subtract points with different dimensions. + When trying to create a point with more than two dimensions. + When `intersection` is called with object other than a Point. + + See Also + ======== + + sympy.geometry.line.Segment : Connects two Points + + Examples + ======== + + >>> from sympy import Point2D + >>> from sympy.abc import x + >>> Point2D(1, 2) + Point2D(1, 2) + >>> Point2D([1, 2]) + Point2D(1, 2) + >>> Point2D(0, x) + Point2D(0, x) + + Floats are automatically converted to Rational unless the + evaluate flag is False: + + >>> Point2D(0.5, 0.25) + Point2D(1/2, 1/4) + >>> Point2D(0.5, 0.25, evaluate=False) + Point2D(0.5, 0.25) + + """ + + _ambient_dimension = 2 + + def __new__(cls, *args, _nocheck=False, **kwargs): + if not _nocheck: + kwargs['dim'] = 2 + args = Point(*args, **kwargs) + return GeometryEntity.__new__(cls, *args) + + def __contains__(self, item): + return item == self + + @property + def bounds(self): + """Return a tuple (xmin, ymin, xmax, ymax) representing the bounding + rectangle for the geometric figure. + + """ + + return (self.x, self.y, self.x, self.y) + + def rotate(self, angle, pt=None): + """Rotate ``angle`` radians counterclockwise about Point ``pt``. + + See Also + ======== + + translate, scale + + Examples + ======== + + >>> from sympy import Point2D, pi + >>> t = Point2D(1, 0) + >>> t.rotate(pi/2) + Point2D(0, 1) + >>> t.rotate(pi/2, (2, 0)) + Point2D(2, -1) + + """ + c = cos(angle) + s = sin(angle) + + rv = self + if pt is not None: + pt = Point(pt, dim=2) + rv -= pt + x, y = rv.args + rv = Point(c*x - s*y, s*x + c*y) + if pt is not None: + rv += pt + return rv + + def scale(self, x=1, y=1, pt=None): + """Scale the coordinates of the Point by multiplying by + ``x`` and ``y`` after subtracting ``pt`` -- default is (0, 0) -- + and then adding ``pt`` back again (i.e. ``pt`` is the point of + reference for the scaling). + + See Also + ======== + + rotate, translate + + Examples + ======== + + >>> from sympy import Point2D + >>> t = Point2D(1, 1) + >>> t.scale(2) + Point2D(2, 1) + >>> t.scale(2, 2) + Point2D(2, 2) + + """ + if pt: + pt = Point(pt, dim=2) + return self.translate(*(-pt).args).scale(x, y).translate(*pt.args) + return Point(self.x*x, self.y*y) + + def transform(self, matrix): + """Return the point after applying the transformation described + by the 3x3 Matrix, ``matrix``. + + See Also + ======== + sympy.geometry.point.Point2D.rotate + sympy.geometry.point.Point2D.scale + sympy.geometry.point.Point2D.translate + """ + if not (matrix.is_Matrix and matrix.shape == (3, 3)): + raise ValueError("matrix must be a 3x3 matrix") + x, y = self.args + return Point(*(Matrix(1, 3, [x, y, 1])*matrix).tolist()[0][:2]) + + def translate(self, x=0, y=0): + """Shift the Point by adding x and y to the coordinates of the Point. + + See Also + ======== + + sympy.geometry.point.Point2D.rotate, scale + + Examples + ======== + + >>> from sympy import Point2D + >>> t = Point2D(0, 1) + >>> t.translate(2) + Point2D(2, 1) + >>> t.translate(2, 2) + Point2D(2, 3) + >>> t + Point2D(2, 2) + Point2D(2, 3) + + """ + return Point(self.x + x, self.y + y) + + @property + def coordinates(self): + """ + Returns the two coordinates of the Point. + + Examples + ======== + + >>> from sympy import Point2D + >>> p = Point2D(0, 1) + >>> p.coordinates + (0, 1) + """ + return self.args + + @property + def x(self): + """ + Returns the X coordinate of the Point. + + Examples + ======== + + >>> from sympy import Point2D + >>> p = Point2D(0, 1) + >>> p.x + 0 + """ + return self.args[0] + + @property + def y(self): + """ + Returns the Y coordinate of the Point. + + Examples + ======== + + >>> from sympy import Point2D + >>> p = Point2D(0, 1) + >>> p.y + 1 + """ + return self.args[1] + +class Point3D(Point): + """A point in a 3-dimensional Euclidean space. + + Parameters + ========== + + coords + A sequence of 3 coordinate values. + + Attributes + ========== + + x + y + z + length + + Raises + ====== + + TypeError + When trying to add or subtract points with different dimensions. + When `intersection` is called with object other than a Point. + + Examples + ======== + + >>> from sympy import Point3D + >>> from sympy.abc import x + >>> Point3D(1, 2, 3) + Point3D(1, 2, 3) + >>> Point3D([1, 2, 3]) + Point3D(1, 2, 3) + >>> Point3D(0, x, 3) + Point3D(0, x, 3) + + Floats are automatically converted to Rational unless the + evaluate flag is False: + + >>> Point3D(0.5, 0.25, 2) + Point3D(1/2, 1/4, 2) + >>> Point3D(0.5, 0.25, 3, evaluate=False) + Point3D(0.5, 0.25, 3) + + """ + + _ambient_dimension = 3 + + def __new__(cls, *args, _nocheck=False, **kwargs): + if not _nocheck: + kwargs['dim'] = 3 + args = Point(*args, **kwargs) + return GeometryEntity.__new__(cls, *args) + + def __contains__(self, item): + return item == self + + @staticmethod + def are_collinear(*points): + """Is a sequence of points collinear? + + Test whether or not a set of points are collinear. Returns True if + the set of points are collinear, or False otherwise. + + Parameters + ========== + + points : sequence of Point + + Returns + ======= + + are_collinear : boolean + + See Also + ======== + + sympy.geometry.line.Line3D + + Examples + ======== + + >>> from sympy import Point3D + >>> from sympy.abc import x + >>> p1, p2 = Point3D(0, 0, 0), Point3D(1, 1, 1) + >>> p3, p4, p5 = Point3D(2, 2, 2), Point3D(x, x, x), Point3D(1, 2, 6) + >>> Point3D.are_collinear(p1, p2, p3, p4) + True + >>> Point3D.are_collinear(p1, p2, p3, p5) + False + """ + return Point.is_collinear(*points) + + def direction_cosine(self, point): + """ + Gives the direction cosine between 2 points + + Parameters + ========== + + p : Point3D + + Returns + ======= + + list + + Examples + ======== + + >>> from sympy import Point3D + >>> p1 = Point3D(1, 2, 3) + >>> p1.direction_cosine(Point3D(2, 3, 5)) + [sqrt(6)/6, sqrt(6)/6, sqrt(6)/3] + """ + a = self.direction_ratio(point) + b = sqrt(Add(*(i**2 for i in a))) + return [(point.x - self.x) / b,(point.y - self.y) / b, + (point.z - self.z) / b] + + def direction_ratio(self, point): + """ + Gives the direction ratio between 2 points + + Parameters + ========== + + p : Point3D + + Returns + ======= + + list + + Examples + ======== + + >>> from sympy import Point3D + >>> p1 = Point3D(1, 2, 3) + >>> p1.direction_ratio(Point3D(2, 3, 5)) + [1, 1, 2] + """ + return [(point.x - self.x),(point.y - self.y),(point.z - self.z)] + + def intersection(self, other): + """The intersection between this point and another GeometryEntity. + + Parameters + ========== + + other : GeometryEntity or sequence of coordinates + + Returns + ======= + + intersection : list of Points + + Notes + ===== + + The return value will either be an empty list if there is no + intersection, otherwise it will contain this point. + + Examples + ======== + + >>> from sympy import Point3D + >>> p1, p2, p3 = Point3D(0, 0, 0), Point3D(1, 1, 1), Point3D(0, 0, 0) + >>> p1.intersection(p2) + [] + >>> p1.intersection(p3) + [Point3D(0, 0, 0)] + + """ + if not isinstance(other, GeometryEntity): + other = Point(other, dim=3) + if isinstance(other, Point3D): + if self == other: + return [self] + return [] + return other.intersection(self) + + def scale(self, x=1, y=1, z=1, pt=None): + """Scale the coordinates of the Point by multiplying by + ``x`` and ``y`` after subtracting ``pt`` -- default is (0, 0) -- + and then adding ``pt`` back again (i.e. ``pt`` is the point of + reference for the scaling). + + See Also + ======== + + translate + + Examples + ======== + + >>> from sympy import Point3D + >>> t = Point3D(1, 1, 1) + >>> t.scale(2) + Point3D(2, 1, 1) + >>> t.scale(2, 2) + Point3D(2, 2, 1) + + """ + if pt: + pt = Point3D(pt) + return self.translate(*(-pt).args).scale(x, y, z).translate(*pt.args) + return Point3D(self.x*x, self.y*y, self.z*z) + + def transform(self, matrix): + """Return the point after applying the transformation described + by the 4x4 Matrix, ``matrix``. + + See Also + ======== + sympy.geometry.point.Point3D.scale + sympy.geometry.point.Point3D.translate + """ + if not (matrix.is_Matrix and matrix.shape == (4, 4)): + raise ValueError("matrix must be a 4x4 matrix") + x, y, z = self.args + m = Transpose(matrix) + return Point3D(*(Matrix(1, 4, [x, y, z, 1])*m).tolist()[0][:3]) + + def translate(self, x=0, y=0, z=0): + """Shift the Point by adding x and y to the coordinates of the Point. + + See Also + ======== + + scale + + Examples + ======== + + >>> from sympy import Point3D + >>> t = Point3D(0, 1, 1) + >>> t.translate(2) + Point3D(2, 1, 1) + >>> t.translate(2, 2) + Point3D(2, 3, 1) + >>> t + Point3D(2, 2, 2) + Point3D(2, 3, 3) + + """ + return Point3D(self.x + x, self.y + y, self.z + z) + + @property + def coordinates(self): + """ + Returns the three coordinates of the Point. + + Examples + ======== + + >>> from sympy import Point3D + >>> p = Point3D(0, 1, 2) + >>> p.coordinates + (0, 1, 2) + """ + return self.args + + @property + def x(self): + """ + Returns the X coordinate of the Point. + + Examples + ======== + + >>> from sympy import Point3D + >>> p = Point3D(0, 1, 3) + >>> p.x + 0 + """ + return self.args[0] + + @property + def y(self): + """ + Returns the Y coordinate of the Point. + + Examples + ======== + + >>> from sympy import Point3D + >>> p = Point3D(0, 1, 2) + >>> p.y + 1 + """ + return self.args[1] + + @property + def z(self): + """ + Returns the Z coordinate of the Point. + + Examples + ======== + + >>> from sympy import Point3D + >>> p = Point3D(0, 1, 1) + >>> p.z + 1 + """ + return self.args[2] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/polygon.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/polygon.py new file mode 100644 index 0000000000000000000000000000000000000000..63031183438e2d228f881fd82e1b0ecca04ec534 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/polygon.py @@ -0,0 +1,2891 @@ +from sympy.core import Expr, S, oo, pi, sympify +from sympy.core.evalf import N +from sympy.core.sorting import default_sort_key, ordered +from sympy.core.symbol import _symbol, Dummy, Symbol +from sympy.functions.elementary.complexes import sign +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import cos, sin, tan +from .ellipse import Circle +from .entity import GeometryEntity, GeometrySet +from .exceptions import GeometryError +from .line import Line, Segment, Ray +from .point import Point +from sympy.logic import And +from sympy.matrices import Matrix +from sympy.simplify.simplify import simplify +from sympy.solvers.solvers import solve +from sympy.utilities.iterables import has_dups, has_variety, uniq, rotate_left, least_rotation +from sympy.utilities.misc import as_int, func_name + +from mpmath.libmp.libmpf import prec_to_dps + +import warnings + + +x, y, T = [Dummy('polygon_dummy', real=True) for i in range(3)] + + +class Polygon(GeometrySet): + """A two-dimensional polygon. + + A simple polygon in space. Can be constructed from a sequence of points + or from a center, radius, number of sides and rotation angle. + + Parameters + ========== + + vertices + A sequence of points. + + n : int, optional + If $> 0$, an n-sided RegularPolygon is created. + Default value is $0$. + + Attributes + ========== + + area + angles + perimeter + vertices + centroid + sides + + Raises + ====== + + GeometryError + If all parameters are not Points. + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.line.Segment, Triangle + + Notes + ===== + + Polygons are treated as closed paths rather than 2D areas so + some calculations can be be negative or positive (e.g., area) + based on the orientation of the points. + + Any consecutive identical points are reduced to a single point + and any points collinear and between two points will be removed + unless they are needed to define an explicit intersection (see examples). + + A Triangle, Segment or Point will be returned when there are 3 or + fewer points provided. + + Examples + ======== + + >>> from sympy import Polygon, pi + >>> p1, p2, p3, p4, p5 = [(0, 0), (1, 0), (5, 1), (0, 1), (3, 0)] + >>> Polygon(p1, p2, p3, p4) + Polygon(Point2D(0, 0), Point2D(1, 0), Point2D(5, 1), Point2D(0, 1)) + >>> Polygon(p1, p2) + Segment2D(Point2D(0, 0), Point2D(1, 0)) + >>> Polygon(p1, p2, p5) + Segment2D(Point2D(0, 0), Point2D(3, 0)) + + The area of a polygon is calculated as positive when vertices are + traversed in a ccw direction. When the sides of a polygon cross the + area will have positive and negative contributions. The following + defines a Z shape where the bottom right connects back to the top + left. + + >>> Polygon((0, 2), (2, 2), (0, 0), (2, 0)).area + 0 + + When the keyword `n` is used to define the number of sides of the + Polygon then a RegularPolygon is created and the other arguments are + interpreted as center, radius and rotation. The unrotated RegularPolygon + will always have a vertex at Point(r, 0) where `r` is the radius of the + circle that circumscribes the RegularPolygon. Its method `spin` can be + used to increment that angle. + + >>> p = Polygon((0,0), 1, n=3) + >>> p + RegularPolygon(Point2D(0, 0), 1, 3, 0) + >>> p.vertices[0] + Point2D(1, 0) + >>> p.args[0] + Point2D(0, 0) + >>> p.spin(pi/2) + >>> p.vertices[0] + Point2D(0, 1) + + """ + + __slots__ = () + + def __new__(cls, *args, n = 0, **kwargs): + if n: + args = list(args) + # return a virtual polygon with n sides + if len(args) == 2: # center, radius + args.append(n) + elif len(args) == 3: # center, radius, rotation + args.insert(2, n) + return RegularPolygon(*args, **kwargs) + + vertices = [Point(a, dim=2, **kwargs) for a in args] + + # remove consecutive duplicates + nodup = [] + for p in vertices: + if nodup and p == nodup[-1]: + continue + nodup.append(p) + if len(nodup) > 1 and nodup[-1] == nodup[0]: + nodup.pop() # last point was same as first + + # remove collinear points + i = -3 + while i < len(nodup) - 3 and len(nodup) > 2: + a, b, c = nodup[i], nodup[i + 1], nodup[i + 2] + if Point.is_collinear(a, b, c): + nodup.pop(i + 1) + if a == c: + nodup.pop(i) + else: + i += 1 + + vertices = list(nodup) + + if len(vertices) > 3: + return GeometryEntity.__new__(cls, *vertices, **kwargs) + elif len(vertices) == 3: + return Triangle(*vertices, **kwargs) + elif len(vertices) == 2: + return Segment(*vertices, **kwargs) + else: + return Point(*vertices, **kwargs) + + @property + def area(self): + """ + The area of the polygon. + + Notes + ===== + + The area calculation can be positive or negative based on the + orientation of the points. If any side of the polygon crosses + any other side, there will be areas having opposite signs. + + See Also + ======== + + sympy.geometry.ellipse.Ellipse.area + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)]) + >>> poly = Polygon(p1, p2, p3, p4) + >>> poly.area + 3 + + In the Z shaped polygon (with the lower right connecting back + to the upper left) the areas cancel out: + + >>> Z = Polygon((0, 1), (1, 1), (0, 0), (1, 0)) + >>> Z.area + 0 + + In the M shaped polygon, areas do not cancel because no side + crosses any other (though there is a point of contact). + + >>> M = Polygon((0, 0), (0, 1), (2, 0), (3, 1), (3, 0)) + >>> M.area + -3/2 + + """ + area = 0 + args = self.args + for i in range(len(args)): + x1, y1 = args[i - 1].args + x2, y2 = args[i].args + area += x1*y2 - x2*y1 + return simplify(area) / 2 + + @staticmethod + def _is_clockwise(a, b, c): + """Return True/False for cw/ccw orientation. + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> a, b, c = [Point(i) for i in [(0, 0), (1, 1), (1, 0)]] + >>> Polygon._is_clockwise(a, b, c) + True + >>> Polygon._is_clockwise(a, c, b) + False + """ + ba = b - a + ca = c - a + t_area = simplify(ba.x*ca.y - ca.x*ba.y) + res = t_area.is_nonpositive + if res is None: + raise ValueError("Can't determine orientation") + return res + + @property + def angles(self): + """The internal angle at each vertex. + + Returns + ======= + + angles : dict + A dictionary where each key is a vertex and each value is the + internal angle at that vertex. The vertices are represented as + Points. + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.line.LinearEntity.angle_between + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)]) + >>> poly = Polygon(p1, p2, p3, p4) + >>> poly.angles[p1] + pi/2 + >>> poly.angles[p2] + acos(-4*sqrt(17)/17) + + """ + + args = self.vertices + n = len(args) + ret = {} + for i in range(n): + a, b, c = args[i - 2], args[i - 1], args[i] + reflex_ang = Ray(b, a).angle_between(Ray(b, c)) + if self._is_clockwise(a, b, c): + ret[b] = 2*S.Pi - reflex_ang + else: + ret[b] = reflex_ang + + # internal sum should be pi*(n - 2), not pi*(n+2) + # so if ratio is (n+2)/(n-2) > 1 it is wrong + wrong = ((sum(ret.values())/S.Pi-1)/(n - 2) - 1).is_positive + if wrong: + two_pi = 2*S.Pi + for b in ret: + ret[b] = two_pi - ret[b] + elif wrong is None: + raise ValueError("could not determine Polygon orientation.") + return ret + + @property + def ambient_dimension(self): + return self.vertices[0].ambient_dimension + + @property + def perimeter(self): + """The perimeter of the polygon. + + Returns + ======= + + perimeter : number or Basic instance + + See Also + ======== + + sympy.geometry.line.Segment.length + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)]) + >>> poly = Polygon(p1, p2, p3, p4) + >>> poly.perimeter + sqrt(17) + 7 + """ + p = 0 + args = self.vertices + for i in range(len(args)): + p += args[i - 1].distance(args[i]) + return simplify(p) + + @property + def vertices(self): + """The vertices of the polygon. + + Returns + ======= + + vertices : list of Points + + Notes + ===== + + When iterating over the vertices, it is more efficient to index self + rather than to request the vertices and index them. Only use the + vertices when you want to process all of them at once. This is even + more important with RegularPolygons that calculate each vertex. + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)]) + >>> poly = Polygon(p1, p2, p3, p4) + >>> poly.vertices + [Point2D(0, 0), Point2D(1, 0), Point2D(5, 1), Point2D(0, 1)] + >>> poly.vertices[0] + Point2D(0, 0) + + """ + return list(self.args) + + @property + def centroid(self): + """The centroid of the polygon. + + Returns + ======= + + centroid : Point + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.util.centroid + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)]) + >>> poly = Polygon(p1, p2, p3, p4) + >>> poly.centroid + Point2D(31/18, 11/18) + + """ + A = 1/(6*self.area) + cx, cy = 0, 0 + args = self.args + for i in range(len(args)): + x1, y1 = args[i - 1].args + x2, y2 = args[i].args + v = x1*y2 - x2*y1 + cx += v*(x1 + x2) + cy += v*(y1 + y2) + return Point(simplify(A*cx), simplify(A*cy)) + + + def second_moment_of_area(self, point=None): + """Returns the second moment and product moment of area of a two dimensional polygon. + + Parameters + ========== + + point : Point, two-tuple of sympifyable objects, or None(default=None) + point is the point about which second moment of area is to be found. + If "point=None" it will be calculated about the axis passing through the + centroid of the polygon. + + Returns + ======= + + I_xx, I_yy, I_xy : number or SymPy expression + I_xx, I_yy are second moment of area of a two dimensional polygon. + I_xy is product moment of area of a two dimensional polygon. + + Examples + ======== + + >>> from sympy import Polygon, symbols + >>> a, b = symbols('a, b') + >>> p1, p2, p3, p4, p5 = [(0, 0), (a, 0), (a, b), (0, b), (a/3, b/3)] + >>> rectangle = Polygon(p1, p2, p3, p4) + >>> rectangle.second_moment_of_area() + (a*b**3/12, a**3*b/12, 0) + >>> rectangle.second_moment_of_area(p5) + (a*b**3/9, a**3*b/9, a**2*b**2/36) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Second_moment_of_area + + """ + + I_xx, I_yy, I_xy = 0, 0, 0 + args = self.vertices + for i in range(len(args)): + x1, y1 = args[i-1].args + x2, y2 = args[i].args + v = x1*y2 - x2*y1 + I_xx += (y1**2 + y1*y2 + y2**2)*v + I_yy += (x1**2 + x1*x2 + x2**2)*v + I_xy += (x1*y2 + 2*x1*y1 + 2*x2*y2 + x2*y1)*v + A = self.area + c_x = self.centroid[0] + c_y = self.centroid[1] + # parallel axis theorem + I_xx_c = (I_xx/12) - (A*(c_y**2)) + I_yy_c = (I_yy/12) - (A*(c_x**2)) + I_xy_c = (I_xy/24) - (A*(c_x*c_y)) + if point is None: + return I_xx_c, I_yy_c, I_xy_c + + I_xx = (I_xx_c + A*((point[1]-c_y)**2)) + I_yy = (I_yy_c + A*((point[0]-c_x)**2)) + I_xy = (I_xy_c + A*((point[0]-c_x)*(point[1]-c_y))) + + return I_xx, I_yy, I_xy + + + def first_moment_of_area(self, point=None): + """ + Returns the first moment of area of a two-dimensional polygon with + respect to a certain point of interest. + + First moment of area is a measure of the distribution of the area + of a polygon in relation to an axis. The first moment of area of + the entire polygon about its own centroid is always zero. Therefore, + here it is calculated for an area, above or below a certain point + of interest, that makes up a smaller portion of the polygon. This + area is bounded by the point of interest and the extreme end + (top or bottom) of the polygon. The first moment for this area is + is then determined about the centroidal axis of the initial polygon. + + References + ========== + + .. [1] https://skyciv.com/docs/tutorials/section-tutorials/calculating-the-statical-or-first-moment-of-area-of-beam-sections/?cc=BMD + .. [2] https://mechanicalc.com/reference/cross-sections + + Parameters + ========== + + point: Point, two-tuple of sympifyable objects, or None (default=None) + point is the point above or below which the area of interest lies + If ``point=None`` then the centroid acts as the point of interest. + + Returns + ======= + + Q_x, Q_y: number or SymPy expressions + Q_x is the first moment of area about the x-axis + Q_y is the first moment of area about the y-axis + A negative sign indicates that the section modulus is + determined for a section below (or left of) the centroidal axis + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> a, b = 50, 10 + >>> p1, p2, p3, p4 = [(0, b), (0, 0), (a, 0), (a, b)] + >>> p = Polygon(p1, p2, p3, p4) + >>> p.first_moment_of_area() + (625, 3125) + >>> p.first_moment_of_area(point=Point(30, 7)) + (525, 3000) + """ + if point: + xc, yc = self.centroid + else: + point = self.centroid + xc, yc = point + + h_line = Line(point, slope=0) + v_line = Line(point, slope=S.Infinity) + + h_poly = self.cut_section(h_line) + v_poly = self.cut_section(v_line) + + poly_1 = h_poly[0] if h_poly[0].area <= h_poly[1].area else h_poly[1] + poly_2 = v_poly[0] if v_poly[0].area <= v_poly[1].area else v_poly[1] + + Q_x = (poly_1.centroid.y - yc)*poly_1.area + Q_y = (poly_2.centroid.x - xc)*poly_2.area + + return Q_x, Q_y + + + def polar_second_moment_of_area(self): + """Returns the polar modulus of a two-dimensional polygon + + It is a constituent of the second moment of area, linked through + the perpendicular axis theorem. While the planar second moment of + area describes an object's resistance to deflection (bending) when + subjected to a force applied to a plane parallel to the central + axis, the polar second moment of area describes an object's + resistance to deflection when subjected to a moment applied in a + plane perpendicular to the object's central axis (i.e. parallel to + the cross-section) + + Examples + ======== + + >>> from sympy import Polygon, symbols + >>> a, b = symbols('a, b') + >>> rectangle = Polygon((0, 0), (a, 0), (a, b), (0, b)) + >>> rectangle.polar_second_moment_of_area() + a**3*b/12 + a*b**3/12 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Polar_moment_of_inertia + + """ + second_moment = self.second_moment_of_area() + return second_moment[0] + second_moment[1] + + + def section_modulus(self, point=None): + """Returns a tuple with the section modulus of a two-dimensional + polygon. + + Section modulus is a geometric property of a polygon defined as the + ratio of second moment of area to the distance of the extreme end of + the polygon from the centroidal axis. + + Parameters + ========== + + point : Point, two-tuple of sympifyable objects, or None(default=None) + point is the point at which section modulus is to be found. + If "point=None" it will be calculated for the point farthest from the + centroidal axis of the polygon. + + Returns + ======= + + S_x, S_y: numbers or SymPy expressions + S_x is the section modulus with respect to the x-axis + S_y is the section modulus with respect to the y-axis + A negative sign indicates that the section modulus is + determined for a point below the centroidal axis + + Examples + ======== + + >>> from sympy import symbols, Polygon, Point + >>> a, b = symbols('a, b', positive=True) + >>> rectangle = Polygon((0, 0), (a, 0), (a, b), (0, b)) + >>> rectangle.section_modulus() + (a*b**2/6, a**2*b/6) + >>> rectangle.section_modulus(Point(a/4, b/4)) + (-a*b**2/3, -a**2*b/3) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Section_modulus + + """ + x_c, y_c = self.centroid + if point is None: + # taking x and y as maximum distances from centroid + x_min, y_min, x_max, y_max = self.bounds + y = max(y_c - y_min, y_max - y_c) + x = max(x_c - x_min, x_max - x_c) + else: + # taking x and y as distances of the given point from the centroid + y = point.y - y_c + x = point.x - x_c + + second_moment= self.second_moment_of_area() + S_x = second_moment[0]/y + S_y = second_moment[1]/x + + return S_x, S_y + + + @property + def sides(self): + """The directed line segments that form the sides of the polygon. + + Returns + ======= + + sides : list of sides + Each side is a directed Segment. + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.line.Segment + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)]) + >>> poly = Polygon(p1, p2, p3, p4) + >>> poly.sides + [Segment2D(Point2D(0, 0), Point2D(1, 0)), + Segment2D(Point2D(1, 0), Point2D(5, 1)), + Segment2D(Point2D(5, 1), Point2D(0, 1)), Segment2D(Point2D(0, 1), Point2D(0, 0))] + + """ + res = [] + args = self.vertices + for i in range(-len(args), 0): + res.append(Segment(args[i], args[i + 1])) + return res + + @property + def bounds(self): + """Return a tuple (xmin, ymin, xmax, ymax) representing the bounding + rectangle for the geometric figure. + + """ + + verts = self.vertices + xs = [p.x for p in verts] + ys = [p.y for p in verts] + return (min(xs), min(ys), max(xs), max(ys)) + + def is_convex(self): + """Is the polygon convex? + + A polygon is convex if all its interior angles are less than 180 + degrees and there are no intersections between sides. + + Returns + ======= + + is_convex : boolean + True if this polygon is convex, False otherwise. + + See Also + ======== + + sympy.geometry.util.convex_hull + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)]) + >>> poly = Polygon(p1, p2, p3, p4) + >>> poly.is_convex() + True + + """ + # Determine orientation of points + args = self.vertices + cw = self._is_clockwise(args[-2], args[-1], args[0]) + for i in range(1, len(args)): + if cw ^ self._is_clockwise(args[i - 2], args[i - 1], args[i]): + return False + # check for intersecting sides + sides = self.sides + for i, si in enumerate(sides): + pts = si.args + # exclude the sides connected to si + for j in range(1 if i == len(sides) - 1 else 0, i - 1): + sj = sides[j] + if sj.p1 not in pts and sj.p2 not in pts: + hit = si.intersection(sj) + if hit: + return False + return True + + def encloses_point(self, p): + """ + Return True if p is enclosed by (is inside of) self. + + Notes + ===== + + Being on the border of self is considered False. + + Parameters + ========== + + p : Point + + Returns + ======= + + encloses_point : True, False or None + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.ellipse.Ellipse.encloses_point + + Examples + ======== + + >>> from sympy import Polygon, Point + >>> p = Polygon((0, 0), (4, 0), (4, 4)) + >>> p.encloses_point(Point(2, 1)) + True + >>> p.encloses_point(Point(2, 2)) + False + >>> p.encloses_point(Point(5, 5)) + False + + References + ========== + + .. [1] https://paulbourke.net/geometry/polygonmesh/#insidepoly + + """ + p = Point(p, dim=2) + if p in self.vertices or any(p in s for s in self.sides): + return False + + # move to p, checking that the result is numeric + lit = [] + for v in self.vertices: + lit.append(v - p) # the difference is simplified + if lit[-1].free_symbols: + return None + + poly = Polygon(*lit) + + # polygon closure is assumed in the following test but Polygon removes duplicate pts so + # the last point has to be added so all sides are computed. Using Polygon.sides is + # not good since Segments are unordered. + args = poly.args + indices = list(range(-len(args), 1)) + + if poly.is_convex(): + orientation = None + for i in indices: + a = args[i] + b = args[i + 1] + test = ((-a.y)*(b.x - a.x) - (-a.x)*(b.y - a.y)).is_negative + if orientation is None: + orientation = test + elif test is not orientation: + return False + return True + + hit_odd = False + p1x, p1y = args[0].args + for i in indices[1:]: + p2x, p2y = args[i].args + if 0 > min(p1y, p2y): + if 0 <= max(p1y, p2y): + if 0 <= max(p1x, p2x): + if p1y != p2y: + xinters = (-p1y)*(p2x - p1x)/(p2y - p1y) + p1x + if p1x == p2x or 0 <= xinters: + hit_odd = not hit_odd + p1x, p1y = p2x, p2y + return hit_odd + + def arbitrary_point(self, parameter='t'): + """A parameterized point on the polygon. + + The parameter, varying from 0 to 1, assigns points to the position on + the perimeter that is that fraction of the total perimeter. So the + point evaluated at t=1/2 would return the point from the first vertex + that is 1/2 way around the polygon. + + Parameters + ========== + + parameter : str, optional + Default value is 't'. + + Returns + ======= + + arbitrary_point : Point + + Raises + ====== + + ValueError + When `parameter` already appears in the Polygon's definition. + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Polygon, Symbol + >>> t = Symbol('t', real=True) + >>> tri = Polygon((0, 0), (1, 0), (1, 1)) + >>> p = tri.arbitrary_point('t') + >>> perimeter = tri.perimeter + >>> s1, s2 = [s.length for s in tri.sides[:2]] + >>> p.subs(t, (s1 + s2/2)/perimeter) + Point2D(1, 1/2) + + """ + t = _symbol(parameter, real=True) + if t.name in (f.name for f in self.free_symbols): + raise ValueError('Symbol %s already appears in object and cannot be used as a parameter.' % t.name) + sides = [] + perimeter = self.perimeter + perim_fraction_start = 0 + for s in self.sides: + side_perim_fraction = s.length/perimeter + perim_fraction_end = perim_fraction_start + side_perim_fraction + pt = s.arbitrary_point(parameter).subs( + t, (t - perim_fraction_start)/side_perim_fraction) + sides.append( + (pt, (And(perim_fraction_start <= t, t < perim_fraction_end)))) + perim_fraction_start = perim_fraction_end + return Piecewise(*sides) + + def parameter_value(self, other, t): + if not isinstance(other,GeometryEntity): + other = Point(other, dim=self.ambient_dimension) + if not isinstance(other,Point): + raise ValueError("other must be a point") + if other.free_symbols: + raise NotImplementedError('non-numeric coordinates') + unknown = False + p = self.arbitrary_point(T) + for pt, cond in p.args: + sol = solve(pt - other, T, dict=True) + if not sol: + continue + value = sol[0][T] + if simplify(cond.subs(T, value)) == True: + return {t: value} + unknown = True + if unknown: + raise ValueError("Given point may not be on %s" % func_name(self)) + raise ValueError("Given point is not on %s" % func_name(self)) + + def plot_interval(self, parameter='t'): + """The plot interval for the default geometric plot of the polygon. + + Parameters + ========== + + parameter : str, optional + Default value is 't'. + + Returns + ======= + + plot_interval : list (plot interval) + [parameter, lower_bound, upper_bound] + + Examples + ======== + + >>> from sympy import Polygon + >>> p = Polygon((0, 0), (1, 0), (1, 1)) + >>> p.plot_interval() + [t, 0, 1] + + """ + t = Symbol(parameter, real=True) + return [t, 0, 1] + + def intersection(self, o): + """The intersection of polygon and geometry entity. + + The intersection may be empty and can contain individual Points and + complete Line Segments. + + Parameters + ========== + + other: GeometryEntity + + Returns + ======= + + intersection : list + The list of Segments and Points + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.line.Segment + + Examples + ======== + + >>> from sympy import Point, Polygon, Line + >>> p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)]) + >>> poly1 = Polygon(p1, p2, p3, p4) + >>> p5, p6, p7 = map(Point, [(3, 2), (1, -1), (0, 2)]) + >>> poly2 = Polygon(p5, p6, p7) + >>> poly1.intersection(poly2) + [Point2D(1/3, 1), Point2D(2/3, 0), Point2D(9/5, 1/5), Point2D(7/3, 1)] + >>> poly1.intersection(Line(p1, p2)) + [Segment2D(Point2D(0, 0), Point2D(1, 0))] + >>> poly1.intersection(p1) + [Point2D(0, 0)] + """ + intersection_result = [] + k = o.sides if isinstance(o, Polygon) else [o] + for side in self.sides: + for side1 in k: + intersection_result.extend(side.intersection(side1)) + + intersection_result = list(uniq(intersection_result)) + points = [entity for entity in intersection_result if isinstance(entity, Point)] + segments = [entity for entity in intersection_result if isinstance(entity, Segment)] + + if points and segments: + points_in_segments = list(uniq([point for point in points for segment in segments if point in segment])) + if points_in_segments: + for i in points_in_segments: + points.remove(i) + return list(ordered(segments + points)) + else: + return list(ordered(intersection_result)) + + + def cut_section(self, line): + """ + Returns a tuple of two polygon segments that lie above and below + the intersecting line respectively. + + Parameters + ========== + + line: Line object of geometry module + line which cuts the Polygon. The part of the Polygon that lies + above and below this line is returned. + + Returns + ======= + + upper_polygon, lower_polygon: Polygon objects or None + upper_polygon is the polygon that lies above the given line. + lower_polygon is the polygon that lies below the given line. + upper_polygon and lower polygon are ``None`` when no polygon + exists above the line or below the line. + + Raises + ====== + + ValueError: When the line does not intersect the polygon + + Examples + ======== + + >>> from sympy import Polygon, Line + >>> a, b = 20, 10 + >>> p1, p2, p3, p4 = [(0, b), (0, 0), (a, 0), (a, b)] + >>> rectangle = Polygon(p1, p2, p3, p4) + >>> t = rectangle.cut_section(Line((0, 5), slope=0)) + >>> t + (Polygon(Point2D(0, 10), Point2D(0, 5), Point2D(20, 5), Point2D(20, 10)), + Polygon(Point2D(0, 5), Point2D(0, 0), Point2D(20, 0), Point2D(20, 5))) + >>> upper_segment, lower_segment = t + >>> upper_segment.area + 100 + >>> upper_segment.centroid + Point2D(10, 15/2) + >>> lower_segment.centroid + Point2D(10, 5/2) + + References + ========== + + .. [1] https://github.com/sympy/sympy/wiki/A-method-to-return-a-cut-section-of-any-polygon-geometry + + """ + intersection_points = self.intersection(line) + if not intersection_points: + raise ValueError("This line does not intersect the polygon") + + points = list(self.vertices) + points.append(points[0]) + + eq = line.equation(x, y) + + # considering equation of line to be `ax +by + c` + a = eq.coeff(x) + b = eq.coeff(y) + + upper_vertices = [] + lower_vertices = [] + # prev is true when previous point is above the line + prev = True + prev_point = None + for point in points: + # when coefficient of y is 0, right side of the line is + # considered + compare = eq.subs({x: point.x, y: point.y})/b if b \ + else eq.subs(x, point.x)/a + + # if point lies above line + if compare > 0: + if not prev: + # if previous point lies below the line, the intersection + # point of the polygon edge and the line has to be included + edge = Line(point, prev_point) + new_point = edge.intersection(line) + upper_vertices.append(new_point[0]) + lower_vertices.append(new_point[0]) + + upper_vertices.append(point) + prev = True + else: + if prev and prev_point: + edge = Line(point, prev_point) + new_point = edge.intersection(line) + upper_vertices.append(new_point[0]) + lower_vertices.append(new_point[0]) + lower_vertices.append(point) + prev = False + prev_point = point + + upper_polygon, lower_polygon = None, None + if upper_vertices and isinstance(Polygon(*upper_vertices), Polygon): + upper_polygon = Polygon(*upper_vertices) + if lower_vertices and isinstance(Polygon(*lower_vertices), Polygon): + lower_polygon = Polygon(*lower_vertices) + + return upper_polygon, lower_polygon + + + def distance(self, o): + """ + Returns the shortest distance between self and o. + + If o is a point, then self does not need to be convex. + If o is another polygon self and o must be convex. + + Examples + ======== + + >>> from sympy import Point, Polygon, RegularPolygon + >>> p1, p2 = map(Point, [(0, 0), (7, 5)]) + >>> poly = Polygon(*RegularPolygon(p1, 1, 3).vertices) + >>> poly.distance(p2) + sqrt(61) + """ + if isinstance(o, Point): + dist = oo + for side in self.sides: + current = side.distance(o) + if current == 0: + return S.Zero + elif current < dist: + dist = current + return dist + elif isinstance(o, Polygon) and self.is_convex() and o.is_convex(): + return self._do_poly_distance(o) + raise NotImplementedError() + + def _do_poly_distance(self, e2): + """ + Calculates the least distance between the exteriors of two + convex polygons e1 and e2. Does not check for the convexity + of the polygons as this is checked by Polygon.distance. + + Notes + ===== + + - Prints a warning if the two polygons possibly intersect as the return + value will not be valid in such a case. For a more through test of + intersection use intersection(). + + See Also + ======== + + sympy.geometry.point.Point.distance + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> square = Polygon(Point(0, 0), Point(0, 1), Point(1, 1), Point(1, 0)) + >>> triangle = Polygon(Point(1, 2), Point(2, 2), Point(2, 1)) + >>> square._do_poly_distance(triangle) + sqrt(2)/2 + + Description of method used + ========================== + + Method: + [1] https://web.archive.org/web/20150509035744/http://cgm.cs.mcgill.ca/~orm/mind2p.html + Uses rotating calipers: + [2] https://en.wikipedia.org/wiki/Rotating_calipers + and antipodal points: + [3] https://en.wikipedia.org/wiki/Antipodal_point + """ + e1 = self + + '''Tests for a possible intersection between the polygons and outputs a warning''' + e1_center = e1.centroid + e2_center = e2.centroid + e1_max_radius = S.Zero + e2_max_radius = S.Zero + for vertex in e1.vertices: + r = Point.distance(e1_center, vertex) + if e1_max_radius < r: + e1_max_radius = r + for vertex in e2.vertices: + r = Point.distance(e2_center, vertex) + if e2_max_radius < r: + e2_max_radius = r + center_dist = Point.distance(e1_center, e2_center) + if center_dist <= e1_max_radius + e2_max_radius: + warnings.warn("Polygons may intersect producing erroneous output", + stacklevel=3) + + ''' + Find the upper rightmost vertex of e1 and the lowest leftmost vertex of e2 + ''' + e1_ymax = Point(0, -oo) + e2_ymin = Point(0, oo) + + for vertex in e1.vertices: + if vertex.y > e1_ymax.y or (vertex.y == e1_ymax.y and vertex.x > e1_ymax.x): + e1_ymax = vertex + for vertex in e2.vertices: + if vertex.y < e2_ymin.y or (vertex.y == e2_ymin.y and vertex.x < e2_ymin.x): + e2_ymin = vertex + min_dist = Point.distance(e1_ymax, e2_ymin) + + ''' + Produce a dictionary with vertices of e1 as the keys and, for each vertex, the points + to which the vertex is connected as its value. The same is then done for e2. + ''' + e1_connections = {} + e2_connections = {} + + for side in e1.sides: + if side.p1 in e1_connections: + e1_connections[side.p1].append(side.p2) + else: + e1_connections[side.p1] = [side.p2] + + if side.p2 in e1_connections: + e1_connections[side.p2].append(side.p1) + else: + e1_connections[side.p2] = [side.p1] + + for side in e2.sides: + if side.p1 in e2_connections: + e2_connections[side.p1].append(side.p2) + else: + e2_connections[side.p1] = [side.p2] + + if side.p2 in e2_connections: + e2_connections[side.p2].append(side.p1) + else: + e2_connections[side.p2] = [side.p1] + + e1_current = e1_ymax + e2_current = e2_ymin + support_line = Line(Point(S.Zero, S.Zero), Point(S.One, S.Zero)) + + ''' + Determine which point in e1 and e2 will be selected after e2_ymin and e1_ymax, + this information combined with the above produced dictionaries determines the + path that will be taken around the polygons + ''' + point1 = e1_connections[e1_ymax][0] + point2 = e1_connections[e1_ymax][1] + angle1 = support_line.angle_between(Line(e1_ymax, point1)) + angle2 = support_line.angle_between(Line(e1_ymax, point2)) + if angle1 < angle2: + e1_next = point1 + elif angle2 < angle1: + e1_next = point2 + elif Point.distance(e1_ymax, point1) > Point.distance(e1_ymax, point2): + e1_next = point2 + else: + e1_next = point1 + + point1 = e2_connections[e2_ymin][0] + point2 = e2_connections[e2_ymin][1] + angle1 = support_line.angle_between(Line(e2_ymin, point1)) + angle2 = support_line.angle_between(Line(e2_ymin, point2)) + if angle1 > angle2: + e2_next = point1 + elif angle2 > angle1: + e2_next = point2 + elif Point.distance(e2_ymin, point1) > Point.distance(e2_ymin, point2): + e2_next = point2 + else: + e2_next = point1 + + ''' + Loop which determines the distance between anti-podal pairs and updates the + minimum distance accordingly. It repeats until it reaches the starting position. + ''' + while True: + e1_angle = support_line.angle_between(Line(e1_current, e1_next)) + e2_angle = pi - support_line.angle_between(Line( + e2_current, e2_next)) + + if (e1_angle < e2_angle) is True: + support_line = Line(e1_current, e1_next) + e1_segment = Segment(e1_current, e1_next) + min_dist_current = e1_segment.distance(e2_current) + + if min_dist_current.evalf() < min_dist.evalf(): + min_dist = min_dist_current + + if e1_connections[e1_next][0] != e1_current: + e1_current = e1_next + e1_next = e1_connections[e1_next][0] + else: + e1_current = e1_next + e1_next = e1_connections[e1_next][1] + elif (e1_angle > e2_angle) is True: + support_line = Line(e2_next, e2_current) + e2_segment = Segment(e2_current, e2_next) + min_dist_current = e2_segment.distance(e1_current) + + if min_dist_current.evalf() < min_dist.evalf(): + min_dist = min_dist_current + + if e2_connections[e2_next][0] != e2_current: + e2_current = e2_next + e2_next = e2_connections[e2_next][0] + else: + e2_current = e2_next + e2_next = e2_connections[e2_next][1] + else: + support_line = Line(e1_current, e1_next) + e1_segment = Segment(e1_current, e1_next) + e2_segment = Segment(e2_current, e2_next) + min1 = e1_segment.distance(e2_next) + min2 = e2_segment.distance(e1_next) + + min_dist_current = min(min1, min2) + if min_dist_current.evalf() < min_dist.evalf(): + min_dist = min_dist_current + + if e1_connections[e1_next][0] != e1_current: + e1_current = e1_next + e1_next = e1_connections[e1_next][0] + else: + e1_current = e1_next + e1_next = e1_connections[e1_next][1] + + if e2_connections[e2_next][0] != e2_current: + e2_current = e2_next + e2_next = e2_connections[e2_next][0] + else: + e2_current = e2_next + e2_next = e2_connections[e2_next][1] + if e1_current == e1_ymax and e2_current == e2_ymin: + break + return min_dist + + def _svg(self, scale_factor=1., fill_color="#66cc99"): + """Returns SVG path element for the Polygon. + + Parameters + ========== + + scale_factor : float + Multiplication factor for the SVG stroke-width. Default is 1. + fill_color : str, optional + Hex string for fill color. Default is "#66cc99". + """ + verts = map(N, self.vertices) + coords = ["{},{}".format(p.x, p.y) for p in verts] + path = "M {} L {} z".format(coords[0], " L ".join(coords[1:])) + return ( + '' + ).format(2. * scale_factor, path, fill_color) + + def _hashable_content(self): + + D = {} + def ref_list(point_list): + kee = {} + for i, p in enumerate(ordered(set(point_list))): + kee[p] = i + D[i] = p + return [kee[p] for p in point_list] + + S1 = ref_list(self.args) + r_nor = rotate_left(S1, least_rotation(S1)) + S2 = ref_list(list(reversed(self.args))) + r_rev = rotate_left(S2, least_rotation(S2)) + if r_nor < r_rev: + r = r_nor + else: + r = r_rev + canonical_args = [ D[order] for order in r ] + return tuple(canonical_args) + + def __contains__(self, o): + """ + Return True if o is contained within the boundary lines of self.altitudes + + Parameters + ========== + + other : GeometryEntity + + Returns + ======= + + contained in : bool + The points (and sides, if applicable) are contained in self. + + See Also + ======== + + sympy.geometry.entity.GeometryEntity.encloses + + Examples + ======== + + >>> from sympy import Line, Segment, Point + >>> p = Point(0, 0) + >>> q = Point(1, 1) + >>> s = Segment(p, q*2) + >>> l = Line(p, q) + >>> p in q + False + >>> p in s + True + >>> q*3 in s + False + >>> s in l + True + + """ + + if isinstance(o, Polygon): + return self == o + elif isinstance(o, Segment): + return any(o in s for s in self.sides) + elif isinstance(o, Point): + if o in self.vertices: + return True + for side in self.sides: + if o in side: + return True + + return False + + def bisectors(p, prec=None): + """Returns angle bisectors of a polygon. If prec is given + then approximate the point defining the ray to that precision. + + The distance between the points defining the bisector ray is 1. + + Examples + ======== + + >>> from sympy import Polygon, Point + >>> p = Polygon(Point(0, 0), Point(2, 0), Point(1, 1), Point(0, 3)) + >>> p.bisectors(2) + {Point2D(0, 0): Ray2D(Point2D(0, 0), Point2D(0.71, 0.71)), + Point2D(0, 3): Ray2D(Point2D(0, 3), Point2D(0.23, 2.0)), + Point2D(1, 1): Ray2D(Point2D(1, 1), Point2D(0.19, 0.42)), + Point2D(2, 0): Ray2D(Point2D(2, 0), Point2D(1.1, 0.38))} + """ + b = {} + pts = list(p.args) + pts.append(pts[0]) # close it + cw = Polygon._is_clockwise(*pts[:3]) + if cw: + pts = list(reversed(pts)) + for v, a in p.angles.items(): + i = pts.index(v) + p1, p2 = Point._normalize_dimension(pts[i], pts[i + 1]) + ray = Ray(p1, p2).rotate(a/2, v) + dir = ray.direction + ray = Ray(ray.p1, ray.p1 + dir/dir.distance((0, 0))) + if prec is not None: + ray = Ray(ray.p1, ray.p2.n(prec)) + b[v] = ray + return b + + +class RegularPolygon(Polygon): + """ + A regular polygon. + + Such a polygon has all internal angles equal and all sides the same length. + + Parameters + ========== + + center : Point + radius : number or Basic instance + The distance from the center to a vertex + n : int + The number of sides + + Attributes + ========== + + vertices + center + radius + rotation + apothem + interior_angle + exterior_angle + circumcircle + incircle + angles + + Raises + ====== + + GeometryError + If the `center` is not a Point, or the `radius` is not a number or Basic + instance, or the number of sides, `n`, is less than three. + + Notes + ===== + + A RegularPolygon can be instantiated with Polygon with the kwarg n. + + Regular polygons are instantiated with a center, radius, number of sides + and a rotation angle. Whereas the arguments of a Polygon are vertices, the + vertices of the RegularPolygon must be obtained with the vertices method. + + See Also + ======== + + sympy.geometry.point.Point, Polygon + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> r = RegularPolygon(Point(0, 0), 5, 3) + >>> r + RegularPolygon(Point2D(0, 0), 5, 3, 0) + >>> r.vertices[0] + Point2D(5, 0) + + """ + + __slots__ = ('_n', '_center', '_radius', '_rot') + + def __new__(self, c, r, n, rot=0, **kwargs): + r, n, rot = map(sympify, (r, n, rot)) + c = Point(c, dim=2, **kwargs) + if not isinstance(r, Expr): + raise GeometryError("r must be an Expr object, not %s" % r) + if n.is_Number: + as_int(n) # let an error raise if necessary + if n < 3: + raise GeometryError("n must be a >= 3, not %s" % n) + + obj = GeometryEntity.__new__(self, c, r, n, **kwargs) + obj._n = n + obj._center = c + obj._radius = r + obj._rot = rot % (2*S.Pi/n) if rot.is_number else rot + return obj + + def _eval_evalf(self, prec=15, **options): + c, r, n, a = self.args + dps = prec_to_dps(prec) + c, r, a = [i.evalf(n=dps, **options) for i in (c, r, a)] + return self.func(c, r, n, a) + + @property + def args(self): + """ + Returns the center point, the radius, + the number of sides, and the orientation angle. + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> r = RegularPolygon(Point(0, 0), 5, 3) + >>> r.args + (Point2D(0, 0), 5, 3, 0) + """ + return self._center, self._radius, self._n, self._rot + + def __str__(self): + return 'RegularPolygon(%s, %s, %s, %s)' % tuple(self.args) + + def __repr__(self): + return 'RegularPolygon(%s, %s, %s, %s)' % tuple(self.args) + + @property + def area(self): + """Returns the area. + + Examples + ======== + + >>> from sympy import RegularPolygon + >>> square = RegularPolygon((0, 0), 1, 4) + >>> square.area + 2 + >>> _ == square.length**2 + True + """ + c, r, n, rot = self.args + return sign(r)*n*self.length**2/(4*tan(pi/n)) + + @property + def length(self): + """Returns the length of the sides. + + The half-length of the side and the apothem form two legs + of a right triangle whose hypotenuse is the radius of the + regular polygon. + + Examples + ======== + + >>> from sympy import RegularPolygon + >>> from sympy import sqrt + >>> s = square_in_unit_circle = RegularPolygon((0, 0), 1, 4) + >>> s.length + sqrt(2) + >>> sqrt((_/2)**2 + s.apothem**2) == s.radius + True + + """ + return self.radius*2*sin(pi/self._n) + + @property + def center(self): + """The center of the RegularPolygon + + This is also the center of the circumscribing circle. + + Returns + ======= + + center : Point + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.ellipse.Ellipse.center + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> rp = RegularPolygon(Point(0, 0), 5, 4) + >>> rp.center + Point2D(0, 0) + """ + return self._center + + centroid = center + + @property + def circumcenter(self): + """ + Alias for center. + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> rp = RegularPolygon(Point(0, 0), 5, 4) + >>> rp.circumcenter + Point2D(0, 0) + """ + return self.center + + @property + def radius(self): + """Radius of the RegularPolygon + + This is also the radius of the circumscribing circle. + + Returns + ======= + + radius : number or instance of Basic + + See Also + ======== + + sympy.geometry.line.Segment.length, sympy.geometry.ellipse.Circle.radius + + Examples + ======== + + >>> from sympy import Symbol + >>> from sympy import RegularPolygon, Point + >>> radius = Symbol('r') + >>> rp = RegularPolygon(Point(0, 0), radius, 4) + >>> rp.radius + r + + """ + return self._radius + + @property + def circumradius(self): + """ + Alias for radius. + + Examples + ======== + + >>> from sympy import Symbol + >>> from sympy import RegularPolygon, Point + >>> radius = Symbol('r') + >>> rp = RegularPolygon(Point(0, 0), radius, 4) + >>> rp.circumradius + r + """ + return self.radius + + @property + def rotation(self): + """CCW angle by which the RegularPolygon is rotated + + Returns + ======= + + rotation : number or instance of Basic + + Examples + ======== + + >>> from sympy import pi + >>> from sympy.abc import a + >>> from sympy import RegularPolygon, Point + >>> RegularPolygon(Point(0, 0), 3, 4, pi/4).rotation + pi/4 + + Numerical rotation angles are made canonical: + + >>> RegularPolygon(Point(0, 0), 3, 4, a).rotation + a + >>> RegularPolygon(Point(0, 0), 3, 4, pi).rotation + 0 + + """ + return self._rot + + @property + def apothem(self): + """The inradius of the RegularPolygon. + + The apothem/inradius is the radius of the inscribed circle. + + Returns + ======= + + apothem : number or instance of Basic + + See Also + ======== + + sympy.geometry.line.Segment.length, sympy.geometry.ellipse.Circle.radius + + Examples + ======== + + >>> from sympy import Symbol + >>> from sympy import RegularPolygon, Point + >>> radius = Symbol('r') + >>> rp = RegularPolygon(Point(0, 0), radius, 4) + >>> rp.apothem + sqrt(2)*r/2 + + """ + return self.radius * cos(S.Pi/self._n) + + @property + def inradius(self): + """ + Alias for apothem. + + Examples + ======== + + >>> from sympy import Symbol + >>> from sympy import RegularPolygon, Point + >>> radius = Symbol('r') + >>> rp = RegularPolygon(Point(0, 0), radius, 4) + >>> rp.inradius + sqrt(2)*r/2 + """ + return self.apothem + + @property + def interior_angle(self): + """Measure of the interior angles. + + Returns + ======= + + interior_angle : number + + See Also + ======== + + sympy.geometry.line.LinearEntity.angle_between + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> rp = RegularPolygon(Point(0, 0), 4, 8) + >>> rp.interior_angle + 3*pi/4 + + """ + return (self._n - 2)*S.Pi/self._n + + @property + def exterior_angle(self): + """Measure of the exterior angles. + + Returns + ======= + + exterior_angle : number + + See Also + ======== + + sympy.geometry.line.LinearEntity.angle_between + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> rp = RegularPolygon(Point(0, 0), 4, 8) + >>> rp.exterior_angle + pi/4 + + """ + return 2*S.Pi/self._n + + @property + def circumcircle(self): + """The circumcircle of the RegularPolygon. + + Returns + ======= + + circumcircle : Circle + + See Also + ======== + + circumcenter, sympy.geometry.ellipse.Circle + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> rp = RegularPolygon(Point(0, 0), 4, 8) + >>> rp.circumcircle + Circle(Point2D(0, 0), 4) + + """ + return Circle(self.center, self.radius) + + @property + def incircle(self): + """The incircle of the RegularPolygon. + + Returns + ======= + + incircle : Circle + + See Also + ======== + + inradius, sympy.geometry.ellipse.Circle + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> rp = RegularPolygon(Point(0, 0), 4, 7) + >>> rp.incircle + Circle(Point2D(0, 0), 4*cos(pi/7)) + + """ + return Circle(self.center, self.apothem) + + @property + def angles(self): + """ + Returns a dictionary with keys, the vertices of the Polygon, + and values, the interior angle at each vertex. + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> r = RegularPolygon(Point(0, 0), 5, 3) + >>> r.angles + {Point2D(-5/2, -5*sqrt(3)/2): pi/3, + Point2D(-5/2, 5*sqrt(3)/2): pi/3, + Point2D(5, 0): pi/3} + """ + ret = {} + ang = self.interior_angle + for v in self.vertices: + ret[v] = ang + return ret + + def encloses_point(self, p): + """ + Return True if p is enclosed by (is inside of) self. + + Notes + ===== + + Being on the border of self is considered False. + + The general Polygon.encloses_point method is called only if + a point is not within or beyond the incircle or circumcircle, + respectively. + + Parameters + ========== + + p : Point + + Returns + ======= + + encloses_point : True, False or None + + See Also + ======== + + sympy.geometry.ellipse.Ellipse.encloses_point + + Examples + ======== + + >>> from sympy import RegularPolygon, S, Point, Symbol + >>> p = RegularPolygon((0, 0), 3, 4) + >>> p.encloses_point(Point(0, 0)) + True + >>> r, R = p.inradius, p.circumradius + >>> p.encloses_point(Point((r + R)/2, 0)) + True + >>> p.encloses_point(Point(R/2, R/2 + (R - r)/10)) + False + >>> t = Symbol('t', real=True) + >>> p.encloses_point(p.arbitrary_point().subs(t, S.Half)) + False + >>> p.encloses_point(Point(5, 5)) + False + + """ + + c = self.center + d = Segment(c, p).length + if d >= self.radius: + return False + elif d < self.inradius: + return True + else: + # now enumerate the RegularPolygon like a general polygon. + return Polygon.encloses_point(self, p) + + def spin(self, angle): + """Increment *in place* the virtual Polygon's rotation by ccw angle. + + See also: rotate method which moves the center. + + >>> from sympy import Polygon, Point, pi + >>> r = Polygon(Point(0,0), 1, n=3) + >>> r.vertices[0] + Point2D(1, 0) + >>> r.spin(pi/6) + >>> r.vertices[0] + Point2D(sqrt(3)/2, 1/2) + + See Also + ======== + + rotation + rotate : Creates a copy of the RegularPolygon rotated about a Point + + """ + self._rot += angle + + def rotate(self, angle, pt=None): + """Override GeometryEntity.rotate to first rotate the RegularPolygon + about its center. + + >>> from sympy import Point, RegularPolygon, pi + >>> t = RegularPolygon(Point(1, 0), 1, 3) + >>> t.vertices[0] # vertex on x-axis + Point2D(2, 0) + >>> t.rotate(pi/2).vertices[0] # vertex on y axis now + Point2D(0, 2) + + See Also + ======== + + rotation + spin : Rotates a RegularPolygon in place + + """ + + r = type(self)(*self.args) # need a copy or else changes are in-place + r._rot += angle + return GeometryEntity.rotate(r, angle, pt) + + def scale(self, x=1, y=1, pt=None): + """Override GeometryEntity.scale since it is the radius that must be + scaled (if x == y) or else a new Polygon must be returned. + + >>> from sympy import RegularPolygon + + Symmetric scaling returns a RegularPolygon: + + >>> RegularPolygon((0, 0), 1, 4).scale(2, 2) + RegularPolygon(Point2D(0, 0), 2, 4, 0) + + Asymmetric scaling returns a kite as a Polygon: + + >>> RegularPolygon((0, 0), 1, 4).scale(2, 1) + Polygon(Point2D(2, 0), Point2D(0, 1), Point2D(-2, 0), Point2D(0, -1)) + + """ + if pt: + pt = Point(pt, dim=2) + return self.translate(*(-pt).args).scale(x, y).translate(*pt.args) + if x != y: + return Polygon(*self.vertices).scale(x, y) + c, r, n, rot = self.args + r *= x + return self.func(c, r, n, rot) + + def reflect(self, line): + """Override GeometryEntity.reflect since this is not made of only + points. + + Examples + ======== + + >>> from sympy import RegularPolygon, Line + + >>> RegularPolygon((0, 0), 1, 4).reflect(Line((0, 1), slope=-2)) + RegularPolygon(Point2D(4/5, 2/5), -1, 4, atan(4/3)) + + """ + c, r, n, rot = self.args + v = self.vertices[0] + d = v - c + cc = c.reflect(line) + vv = v.reflect(line) + dd = vv - cc + # calculate rotation about the new center + # which will align the vertices + l1 = Ray((0, 0), dd) + l2 = Ray((0, 0), d) + ang = l1.closing_angle(l2) + rot += ang + # change sign of radius as point traversal is reversed + return self.func(cc, -r, n, rot) + + @property + def vertices(self): + """The vertices of the RegularPolygon. + + Returns + ======= + + vertices : list + Each vertex is a Point. + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import RegularPolygon, Point + >>> rp = RegularPolygon(Point(0, 0), 5, 4) + >>> rp.vertices + [Point2D(5, 0), Point2D(0, 5), Point2D(-5, 0), Point2D(0, -5)] + + """ + c = self._center + r = abs(self._radius) + rot = self._rot + v = 2*S.Pi/self._n + + return [Point(c.x + r*cos(k*v + rot), c.y + r*sin(k*v + rot)) + for k in range(self._n)] + + def __eq__(self, o): + if not isinstance(o, Polygon): + return False + elif not isinstance(o, RegularPolygon): + return Polygon.__eq__(o, self) + return self.args == o.args + + def __hash__(self): + return super().__hash__() + + +class Triangle(Polygon): + """ + A polygon with three vertices and three sides. + + Parameters + ========== + + points : sequence of Points + keyword: asa, sas, or sss to specify sides/angles of the triangle + + Attributes + ========== + + vertices + altitudes + orthocenter + circumcenter + circumradius + circumcircle + inradius + incircle + exradii + medians + medial + nine_point_circle + + Raises + ====== + + GeometryError + If the number of vertices is not equal to three, or one of the vertices + is not a Point, or a valid keyword is not given. + + See Also + ======== + + sympy.geometry.point.Point, Polygon + + Examples + ======== + + >>> from sympy import Triangle, Point + >>> Triangle(Point(0, 0), Point(4, 0), Point(4, 3)) + Triangle(Point2D(0, 0), Point2D(4, 0), Point2D(4, 3)) + + Keywords sss, sas, or asa can be used to give the desired + side lengths (in order) and interior angles (in degrees) that + define the triangle: + + >>> Triangle(sss=(3, 4, 5)) + Triangle(Point2D(0, 0), Point2D(3, 0), Point2D(3, 4)) + >>> Triangle(asa=(30, 1, 30)) + Triangle(Point2D(0, 0), Point2D(1, 0), Point2D(1/2, sqrt(3)/6)) + >>> Triangle(sas=(1, 45, 2)) + Triangle(Point2D(0, 0), Point2D(2, 0), Point2D(sqrt(2)/2, sqrt(2)/2)) + + """ + + def __new__(cls, *args, **kwargs): + if len(args) != 3: + if 'sss' in kwargs: + return _sss(*[simplify(a) for a in kwargs['sss']]) + if 'asa' in kwargs: + return _asa(*[simplify(a) for a in kwargs['asa']]) + if 'sas' in kwargs: + return _sas(*[simplify(a) for a in kwargs['sas']]) + msg = "Triangle instantiates with three points or a valid keyword." + raise GeometryError(msg) + + vertices = [Point(a, dim=2, **kwargs) for a in args] + + # remove consecutive duplicates + nodup = [] + for p in vertices: + if nodup and p == nodup[-1]: + continue + nodup.append(p) + if len(nodup) > 1 and nodup[-1] == nodup[0]: + nodup.pop() # last point was same as first + + # remove collinear points + i = -3 + while i < len(nodup) - 3 and len(nodup) > 2: + a, b, c = sorted( + [nodup[i], nodup[i + 1], nodup[i + 2]], key=default_sort_key) + if Point.is_collinear(a, b, c): + nodup[i] = a + nodup[i + 1] = None + nodup.pop(i + 1) + i += 1 + + vertices = list(filter(lambda x: x is not None, nodup)) + + if len(vertices) == 3: + return GeometryEntity.__new__(cls, *vertices, **kwargs) + elif len(vertices) == 2: + return Segment(*vertices, **kwargs) + else: + return Point(*vertices, **kwargs) + + @property + def vertices(self): + """The triangle's vertices + + Returns + ======= + + vertices : tuple + Each element in the tuple is a Point + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Triangle, Point + >>> t = Triangle(Point(0, 0), Point(4, 0), Point(4, 3)) + >>> t.vertices + (Point2D(0, 0), Point2D(4, 0), Point2D(4, 3)) + + """ + return self.args + + def is_similar(t1, t2): + """Is another triangle similar to this one. + + Two triangles are similar if one can be uniformly scaled to the other. + + Parameters + ========== + + other: Triangle + + Returns + ======= + + is_similar : boolean + + See Also + ======== + + sympy.geometry.entity.GeometryEntity.is_similar + + Examples + ======== + + >>> from sympy import Triangle, Point + >>> t1 = Triangle(Point(0, 0), Point(4, 0), Point(4, 3)) + >>> t2 = Triangle(Point(0, 0), Point(-4, 0), Point(-4, -3)) + >>> t1.is_similar(t2) + True + + >>> t2 = Triangle(Point(0, 0), Point(-4, 0), Point(-4, -4)) + >>> t1.is_similar(t2) + False + + """ + if not isinstance(t2, Polygon): + return False + + s1_1, s1_2, s1_3 = [side.length for side in t1.sides] + s2 = [side.length for side in t2.sides] + + def _are_similar(u1, u2, u3, v1, v2, v3): + e1 = simplify(u1/v1) + e2 = simplify(u2/v2) + e3 = simplify(u3/v3) + return bool(e1 == e2) and bool(e2 == e3) + + # There's only 6 permutations, so write them out + return _are_similar(s1_1, s1_2, s1_3, *s2) or \ + _are_similar(s1_1, s1_3, s1_2, *s2) or \ + _are_similar(s1_2, s1_1, s1_3, *s2) or \ + _are_similar(s1_2, s1_3, s1_1, *s2) or \ + _are_similar(s1_3, s1_1, s1_2, *s2) or \ + _are_similar(s1_3, s1_2, s1_1, *s2) + + def is_equilateral(self): + """Are all the sides the same length? + + Returns + ======= + + is_equilateral : boolean + + See Also + ======== + + sympy.geometry.entity.GeometryEntity.is_similar, RegularPolygon + is_isosceles, is_right, is_scalene + + Examples + ======== + + >>> from sympy import Triangle, Point + >>> t1 = Triangle(Point(0, 0), Point(4, 0), Point(4, 3)) + >>> t1.is_equilateral() + False + + >>> from sympy import sqrt + >>> t2 = Triangle(Point(0, 0), Point(10, 0), Point(5, 5*sqrt(3))) + >>> t2.is_equilateral() + True + + """ + return not has_variety(s.length for s in self.sides) + + def is_isosceles(self): + """Are two or more of the sides the same length? + + Returns + ======= + + is_isosceles : boolean + + See Also + ======== + + is_equilateral, is_right, is_scalene + + Examples + ======== + + >>> from sympy import Triangle, Point + >>> t1 = Triangle(Point(0, 0), Point(4, 0), Point(2, 4)) + >>> t1.is_isosceles() + True + + """ + return has_dups(s.length for s in self.sides) + + def is_scalene(self): + """Are all the sides of the triangle of different lengths? + + Returns + ======= + + is_scalene : boolean + + See Also + ======== + + is_equilateral, is_isosceles, is_right + + Examples + ======== + + >>> from sympy import Triangle, Point + >>> t1 = Triangle(Point(0, 0), Point(4, 0), Point(1, 4)) + >>> t1.is_scalene() + True + + """ + return not has_dups(s.length for s in self.sides) + + def is_right(self): + """Is the triangle right-angled. + + Returns + ======= + + is_right : boolean + + See Also + ======== + + sympy.geometry.line.LinearEntity.is_perpendicular + is_equilateral, is_isosceles, is_scalene + + Examples + ======== + + >>> from sympy import Triangle, Point + >>> t1 = Triangle(Point(0, 0), Point(4, 0), Point(4, 3)) + >>> t1.is_right() + True + + """ + s = self.sides + return Segment.is_perpendicular(s[0], s[1]) or \ + Segment.is_perpendicular(s[1], s[2]) or \ + Segment.is_perpendicular(s[0], s[2]) + + @property + def altitudes(self): + """The altitudes of the triangle. + + An altitude of a triangle is a segment through a vertex, + perpendicular to the opposite side, with length being the + height of the vertex measured from the line containing the side. + + Returns + ======= + + altitudes : dict + The dictionary consists of keys which are vertices and values + which are Segments. + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.line.Segment.length + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> t.altitudes[p1] + Segment2D(Point2D(0, 0), Point2D(1/2, 1/2)) + + """ + s = self.sides + v = self.vertices + return {v[0]: s[1].perpendicular_segment(v[0]), + v[1]: s[2].perpendicular_segment(v[1]), + v[2]: s[0].perpendicular_segment(v[2])} + + @property + def orthocenter(self): + """The orthocenter of the triangle. + + The orthocenter is the intersection of the altitudes of a triangle. + It may lie inside, outside or on the triangle. + + Returns + ======= + + orthocenter : Point + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> t.orthocenter + Point2D(0, 0) + + """ + a = self.altitudes + v = self.vertices + return Line(a[v[0]]).intersection(Line(a[v[1]]))[0] + + @property + def circumcenter(self): + """The circumcenter of the triangle + + The circumcenter is the center of the circumcircle. + + Returns + ======= + + circumcenter : Point + + See Also + ======== + + sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> t.circumcenter + Point2D(1/2, 1/2) + """ + a, b, c = [x.perpendicular_bisector() for x in self.sides] + return a.intersection(b)[0] + + @property + def circumradius(self): + """The radius of the circumcircle of the triangle. + + Returns + ======= + + circumradius : number of Basic instance + + See Also + ======== + + sympy.geometry.ellipse.Circle.radius + + Examples + ======== + + >>> from sympy import Symbol + >>> from sympy import Point, Triangle + >>> a = Symbol('a') + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, a) + >>> t = Triangle(p1, p2, p3) + >>> t.circumradius + sqrt(a**2/4 + 1/4) + """ + return Point.distance(self.circumcenter, self.vertices[0]) + + @property + def circumcircle(self): + """The circle which passes through the three vertices of the triangle. + + Returns + ======= + + circumcircle : Circle + + See Also + ======== + + sympy.geometry.ellipse.Circle + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> t.circumcircle + Circle(Point2D(1/2, 1/2), sqrt(2)/2) + + """ + return Circle(self.circumcenter, self.circumradius) + + def bisectors(self): + """The angle bisectors of the triangle. + + An angle bisector of a triangle is a straight line through a vertex + which cuts the corresponding angle in half. + + Returns + ======= + + bisectors : dict + Each key is a vertex (Point) and each value is the corresponding + bisector (Segment). + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.line.Segment + + Examples + ======== + + >>> from sympy import Point, Triangle, Segment + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> from sympy import sqrt + >>> t.bisectors()[p2] == Segment(Point(1, 0), Point(0, sqrt(2) - 1)) + True + + """ + # use lines containing sides so containment check during + # intersection calculation can be avoided, thus reducing + # the processing time for calculating the bisectors + s = [Line(l) for l in self.sides] + v = self.vertices + c = self.incenter + l1 = Segment(v[0], Line(v[0], c).intersection(s[1])[0]) + l2 = Segment(v[1], Line(v[1], c).intersection(s[2])[0]) + l3 = Segment(v[2], Line(v[2], c).intersection(s[0])[0]) + return {v[0]: l1, v[1]: l2, v[2]: l3} + + @property + def incenter(self): + """The center of the incircle. + + The incircle is the circle which lies inside the triangle and touches + all three sides. + + Returns + ======= + + incenter : Point + + See Also + ======== + + incircle, sympy.geometry.point.Point + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> t.incenter + Point2D(1 - sqrt(2)/2, 1 - sqrt(2)/2) + + """ + s = self.sides + l = Matrix([s[i].length for i in [1, 2, 0]]) + p = sum(l) + v = self.vertices + x = simplify(l.dot(Matrix([vi.x for vi in v]))/p) + y = simplify(l.dot(Matrix([vi.y for vi in v]))/p) + return Point(x, y) + + @property + def inradius(self): + """The radius of the incircle. + + Returns + ======= + + inradius : number of Basic instance + + See Also + ======== + + incircle, sympy.geometry.ellipse.Circle.radius + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(4, 0), Point(0, 3) + >>> t = Triangle(p1, p2, p3) + >>> t.inradius + 1 + + """ + return simplify(2 * self.area / self.perimeter) + + @property + def incircle(self): + """The incircle of the triangle. + + The incircle is the circle which lies inside the triangle and touches + all three sides. + + Returns + ======= + + incircle : Circle + + See Also + ======== + + sympy.geometry.ellipse.Circle + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(2, 0), Point(0, 2) + >>> t = Triangle(p1, p2, p3) + >>> t.incircle + Circle(Point2D(2 - sqrt(2), 2 - sqrt(2)), 2 - sqrt(2)) + + """ + return Circle(self.incenter, self.inradius) + + @property + def exradii(self): + """The radius of excircles of a triangle. + + An excircle of the triangle is a circle lying outside the triangle, + tangent to one of its sides and tangent to the extensions of the + other two. + + Returns + ======= + + exradii : dict + + See Also + ======== + + sympy.geometry.polygon.Triangle.inradius + + Examples + ======== + + The exradius touches the side of the triangle to which it is keyed, e.g. + the exradius touching side 2 is: + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(6, 0), Point(0, 2) + >>> t = Triangle(p1, p2, p3) + >>> t.exradii[t.sides[2]] + -2 + sqrt(10) + + References + ========== + + .. [1] https://mathworld.wolfram.com/Exradius.html + .. [2] https://mathworld.wolfram.com/Excircles.html + + """ + + side = self.sides + a = side[0].length + b = side[1].length + c = side[2].length + s = (a+b+c)/2 + area = self.area + exradii = {self.sides[0]: simplify(area/(s-a)), + self.sides[1]: simplify(area/(s-b)), + self.sides[2]: simplify(area/(s-c))} + + return exradii + + @property + def excenters(self): + """Excenters of the triangle. + + An excenter is the center of a circle that is tangent to a side of the + triangle and the extensions of the other two sides. + + Returns + ======= + + excenters : dict + + + Examples + ======== + + The excenters are keyed to the side of the triangle to which their corresponding + excircle is tangent: The center is keyed, e.g. the excenter of a circle touching + side 0 is: + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(6, 0), Point(0, 2) + >>> t = Triangle(p1, p2, p3) + >>> t.excenters[t.sides[0]] + Point2D(12*sqrt(10), 2/3 + sqrt(10)/3) + + See Also + ======== + + sympy.geometry.polygon.Triangle.exradii + + References + ========== + + .. [1] https://mathworld.wolfram.com/Excircles.html + + """ + + s = self.sides + v = self.vertices + a = s[0].length + b = s[1].length + c = s[2].length + x = [v[0].x, v[1].x, v[2].x] + y = [v[0].y, v[1].y, v[2].y] + + exc_coords = { + "x1": simplify(-a*x[0]+b*x[1]+c*x[2]/(-a+b+c)), + "x2": simplify(a*x[0]-b*x[1]+c*x[2]/(a-b+c)), + "x3": simplify(a*x[0]+b*x[1]-c*x[2]/(a+b-c)), + "y1": simplify(-a*y[0]+b*y[1]+c*y[2]/(-a+b+c)), + "y2": simplify(a*y[0]-b*y[1]+c*y[2]/(a-b+c)), + "y3": simplify(a*y[0]+b*y[1]-c*y[2]/(a+b-c)) + } + + excenters = { + s[0]: Point(exc_coords["x1"], exc_coords["y1"]), + s[1]: Point(exc_coords["x2"], exc_coords["y2"]), + s[2]: Point(exc_coords["x3"], exc_coords["y3"]) + } + + return excenters + + @property + def medians(self): + """The medians of the triangle. + + A median of a triangle is a straight line through a vertex and the + midpoint of the opposite side, and divides the triangle into two + equal areas. + + Returns + ======= + + medians : dict + Each key is a vertex (Point) and each value is the median (Segment) + at that point. + + See Also + ======== + + sympy.geometry.point.Point.midpoint, sympy.geometry.line.Segment.midpoint + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> t.medians[p1] + Segment2D(Point2D(0, 0), Point2D(1/2, 1/2)) + + """ + s = self.sides + v = self.vertices + return {v[0]: Segment(v[0], s[1].midpoint), + v[1]: Segment(v[1], s[2].midpoint), + v[2]: Segment(v[2], s[0].midpoint)} + + @property + def medial(self): + """The medial triangle of the triangle. + + The triangle which is formed from the midpoints of the three sides. + + Returns + ======= + + medial : Triangle + + See Also + ======== + + sympy.geometry.line.Segment.midpoint + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> t.medial + Triangle(Point2D(1/2, 0), Point2D(1/2, 1/2), Point2D(0, 1/2)) + + """ + s = self.sides + return Triangle(s[0].midpoint, s[1].midpoint, s[2].midpoint) + + @property + def nine_point_circle(self): + """The nine-point circle of the triangle. + + Nine-point circle is the circumcircle of the medial triangle, which + passes through the feet of altitudes and the middle points of segments + connecting the vertices and the orthocenter. + + Returns + ======= + + nine_point_circle : Circle + + See also + ======== + + sympy.geometry.line.Segment.midpoint + sympy.geometry.polygon.Triangle.medial + sympy.geometry.polygon.Triangle.orthocenter + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> t.nine_point_circle + Circle(Point2D(1/4, 1/4), sqrt(2)/4) + + """ + return Circle(*self.medial.vertices) + + @property + def eulerline(self): + """The Euler line of the triangle. + + The line which passes through circumcenter, centroid and orthocenter. + + Returns + ======= + + eulerline : Line (or Point for equilateral triangles in which case all + centers coincide) + + Examples + ======== + + >>> from sympy import Point, Triangle + >>> p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + >>> t = Triangle(p1, p2, p3) + >>> t.eulerline + Line2D(Point2D(0, 0), Point2D(1/2, 1/2)) + + """ + if self.is_equilateral(): + return self.orthocenter + return Line(self.orthocenter, self.circumcenter) + +def rad(d): + """Return the radian value for the given degrees (pi = 180 degrees).""" + return d*pi/180 + + +def deg(r): + """Return the degree value for the given radians (pi = 180 degrees).""" + return r/pi*180 + + +def _slope(d): + rv = tan(rad(d)) + return rv + + +def _asa(d1, l, d2): + """Return triangle having side with length l on the x-axis.""" + xy = Line((0, 0), slope=_slope(d1)).intersection( + Line((l, 0), slope=_slope(180 - d2)))[0] + return Triangle((0, 0), (l, 0), xy) + + +def _sss(l1, l2, l3): + """Return triangle having side of length l1 on the x-axis.""" + c1 = Circle((0, 0), l3) + c2 = Circle((l1, 0), l2) + inter = [a for a in c1.intersection(c2) if a.y.is_nonnegative] + if not inter: + return None + pt = inter[0] + return Triangle((0, 0), (l1, 0), pt) + + +def _sas(l1, d, l2): + """Return triangle having side with length l2 on the x-axis.""" + p1 = Point(0, 0) + p2 = Point(l2, 0) + p3 = Point(cos(rad(d))*l1, sin(rad(d))*l1) + return Triangle(p1, p2, p3) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_curve.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_curve.py new file mode 100644 index 0000000000000000000000000000000000000000..50aa80273a1d8eb9e414a8d591571f3127352dad --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_curve.py @@ -0,0 +1,120 @@ +from sympy.core.containers import Tuple +from sympy.core.numbers import (Rational, pi) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.hyperbolic import asinh +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.geometry import Curve, Line, Point, Ellipse, Ray, Segment, Circle, Polygon, RegularPolygon +from sympy.testing.pytest import raises, slow + + +def test_curve(): + x = Symbol('x', real=True) + s = Symbol('s') + z = Symbol('z') + + # this curve is independent of the indicated parameter + c = Curve([2*s, s**2], (z, 0, 2)) + + assert c.parameter == z + assert c.functions == (2*s, s**2) + assert c.arbitrary_point() == Point(2*s, s**2) + assert c.arbitrary_point(z) == Point(2*s, s**2) + + # this is how it is normally used + c = Curve([2*s, s**2], (s, 0, 2)) + + assert c.parameter == s + assert c.functions == (2*s, s**2) + t = Symbol('t') + # the t returned as assumptions + assert c.arbitrary_point() != Point(2*t, t**2) + t = Symbol('t', real=True) + # now t has the same assumptions so the test passes + assert c.arbitrary_point() == Point(2*t, t**2) + assert c.arbitrary_point(z) == Point(2*z, z**2) + assert c.arbitrary_point(c.parameter) == Point(2*s, s**2) + assert c.arbitrary_point(None) == Point(2*s, s**2) + assert c.plot_interval() == [t, 0, 2] + assert c.plot_interval(z) == [z, 0, 2] + + assert Curve([x, x], (x, 0, 1)).rotate(pi/2) == Curve([-x, x], (x, 0, 1)) + assert Curve([x, x], (x, 0, 1)).rotate(pi/2, (1, 2)).scale(2, 3).translate( + 1, 3).arbitrary_point(s) == \ + Line((0, 0), (1, 1)).rotate(pi/2, (1, 2)).scale(2, 3).translate( + 1, 3).arbitrary_point(s) == \ + Point(-2*s + 7, 3*s + 6) + + raises(ValueError, lambda: Curve((s), (s, 1, 2))) + raises(ValueError, lambda: Curve((x, x * 2), (1, x))) + + raises(ValueError, lambda: Curve((s, s + t), (s, 1, 2)).arbitrary_point()) + raises(ValueError, lambda: Curve((s, s + t), (t, 1, 2)).arbitrary_point(s)) + + +@slow +def test_free_symbols(): + a, b, c, d, e, f, s = symbols('a:f,s') + assert Point(a, b).free_symbols == {a, b} + assert Line((a, b), (c, d)).free_symbols == {a, b, c, d} + assert Ray((a, b), (c, d)).free_symbols == {a, b, c, d} + assert Ray((a, b), angle=c).free_symbols == {a, b, c} + assert Segment((a, b), (c, d)).free_symbols == {a, b, c, d} + assert Line((a, b), slope=c).free_symbols == {a, b, c} + assert Curve((a*s, b*s), (s, c, d)).free_symbols == {a, b, c, d} + assert Ellipse((a, b), c, d).free_symbols == {a, b, c, d} + assert Ellipse((a, b), c, eccentricity=d).free_symbols == \ + {a, b, c, d} + assert Ellipse((a, b), vradius=c, eccentricity=d).free_symbols == \ + {a, b, c, d} + assert Circle((a, b), c).free_symbols == {a, b, c} + assert Circle((a, b), (c, d), (e, f)).free_symbols == \ + {e, d, c, b, f, a} + assert Polygon((a, b), (c, d), (e, f)).free_symbols == \ + {e, b, d, f, a, c} + assert RegularPolygon((a, b), c, d, e).free_symbols == {e, a, b, c, d} + + +def test_transform(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + c = Curve((x, x**2), (x, 0, 1)) + cout = Curve((2*x - 4, 3*x**2 - 10), (x, 0, 1)) + pts = [Point(0, 0), Point(S.Half, Rational(1, 4)), Point(1, 1)] + pts_out = [Point(-4, -10), Point(-3, Rational(-37, 4)), Point(-2, -7)] + + assert c.scale(2, 3, (4, 5)) == cout + assert [c.subs(x, xi/2) for xi in Tuple(0, 1, 2)] == pts + assert [cout.subs(x, xi/2) for xi in Tuple(0, 1, 2)] == pts_out + assert Curve((x + y, 3*x), (x, 0, 1)).subs(y, S.Half) == \ + Curve((x + S.Half, 3*x), (x, 0, 1)) + assert Curve((x, 3*x), (x, 0, 1)).translate(4, 5) == \ + Curve((x + 4, 3*x + 5), (x, 0, 1)) + + +def test_length(): + t = Symbol('t', real=True) + + c1 = Curve((t, 0), (t, 0, 1)) + assert c1.length == 1 + + c2 = Curve((t, t), (t, 0, 1)) + assert c2.length == sqrt(2) + + c3 = Curve((t ** 2, t), (t, 2, 5)) + assert c3.length == -sqrt(17) - asinh(4) / 4 + asinh(10) / 4 + 5 * sqrt(101) / 2 + + +def test_parameter_value(): + t = Symbol('t') + C = Curve([2*t, t**2], (t, 0, 2)) + assert C.parameter_value((2, 1), t) == {t: 1} + raises(ValueError, lambda: C.parameter_value((2, 0), t)) + + +def test_issue_17997(): + t, s = symbols('t s') + c = Curve((t, t**2), (t, 0, 10)) + p = Curve([2*s, s**2], (s, 0, 2)) + assert c(2) == Point(2, 4) + assert p(1) == Point(2, 1) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_ellipse.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_ellipse.py new file mode 100644 index 0000000000000000000000000000000000000000..a79eba8c35771bda9f0980aca68d937f8e625c0a --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_ellipse.py @@ -0,0 +1,613 @@ +from sympy.core import expand +from sympy.core.numbers import (Rational, oo, pi) +from sympy.core.relational import Eq +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.complexes import Abs +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import sec +from sympy.geometry.line import Segment2D +from sympy.geometry.point import Point2D +from sympy.geometry import (Circle, Ellipse, GeometryError, Line, Point, + Polygon, Ray, RegularPolygon, Segment, + Triangle, intersection) +from sympy.testing.pytest import raises, slow +from sympy.integrals.integrals import integrate +from sympy.functions.special.elliptic_integrals import elliptic_e +from sympy.functions.elementary.miscellaneous import Max + + +def test_ellipse_equation_using_slope(): + from sympy.abc import x, y + + e1 = Ellipse(Point(1, 0), 3, 2) + assert str(e1.equation(_slope=1)) == str((-x + y + 1)**2/8 + (x + y - 1)**2/18 - 1) + + e2 = Ellipse(Point(0, 0), 4, 1) + assert str(e2.equation(_slope=1)) == str((-x + y)**2/2 + (x + y)**2/32 - 1) + + e3 = Ellipse(Point(1, 5), 6, 2) + assert str(e3.equation(_slope=2)) == str((-2*x + y - 3)**2/20 + (x + 2*y - 11)**2/180 - 1) + + +def test_object_from_equation(): + from sympy.abc import x, y, a, b, c, d, e + assert Circle(x**2 + y**2 + 3*x + 4*y - 8) == Circle(Point2D(S(-3) / 2, -2), sqrt(57) / 2) + assert Circle(x**2 + y**2 + 6*x + 8*y + 25) == Circle(Point2D(-3, -4), 0) + assert Circle(a**2 + b**2 + 6*a + 8*b + 25, x='a', y='b') == Circle(Point2D(-3, -4), 0) + assert Circle(x**2 + y**2 - 25) == Circle(Point2D(0, 0), 5) + assert Circle(x**2 + y**2) == Circle(Point2D(0, 0), 0) + assert Circle(a**2 + b**2, x='a', y='b') == Circle(Point2D(0, 0), 0) + assert Circle(x**2 + y**2 + 6*x + 8) == Circle(Point2D(-3, 0), 1) + assert Circle(x**2 + y**2 + 6*y + 8) == Circle(Point2D(0, -3), 1) + assert Circle((x - 1)**2 + y**2 - 9) == Circle(Point2D(1, 0), 3) + assert Circle(6*(x**2) + 6*(y**2) + 6*x + 8*y - 25) == Circle(Point2D(Rational(-1, 2), Rational(-2, 3)), 5*sqrt(7)/6) + assert Circle(Eq(a**2 + b**2, 25), x='a', y=b) == Circle(Point2D(0, 0), 5) + raises(GeometryError, lambda: Circle(x**2 + y**2 + 3*x + 4*y + 26)) + raises(GeometryError, lambda: Circle(x**2 + y**2 + 25)) + raises(GeometryError, lambda: Circle(a**2 + b**2 + 25, x='a', y='b')) + raises(GeometryError, lambda: Circle(x**2 + 6*y + 8)) + raises(GeometryError, lambda: Circle(6*(x ** 2) + 4*(y**2) + 6*x + 8*y + 25)) + raises(ValueError, lambda: Circle(a**2 + b**2 + 3*a + 4*b - 8)) + # .equation() adds 'real=True' assumption; '==' would fail if assumptions differed + x, y = symbols('x y', real=True) + eq = a*x**2 + a*y**2 + c*x + d*y + e + assert expand(Circle(eq).equation()*a) == eq + + +@slow +def test_ellipse_geom(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + t = Symbol('t', real=True) + y1 = Symbol('y1', real=True) + half = S.Half + p1 = Point(0, 0) + p2 = Point(1, 1) + p4 = Point(0, 1) + + e1 = Ellipse(p1, 1, 1) + e2 = Ellipse(p2, half, 1) + e3 = Ellipse(p1, y1, y1) + c1 = Circle(p1, 1) + c2 = Circle(p2, 1) + c3 = Circle(Point(sqrt(2), sqrt(2)), 1) + l1 = Line(p1, p2) + + # Test creation with three points + cen, rad = Point(3*half, 2), 5*half + assert Circle(Point(0, 0), Point(3, 0), Point(0, 4)) == Circle(cen, rad) + assert Circle(Point(0, 0), Point(1, 1), Point(2, 2)) == Segment2D(Point2D(0, 0), Point2D(2, 2)) + + raises(ValueError, lambda: Ellipse(None, None, None, 1)) + raises(ValueError, lambda: Ellipse()) + raises(GeometryError, lambda: Circle(Point(0, 0))) + raises(GeometryError, lambda: Circle(Symbol('x')*Symbol('y'))) + + # Basic Stuff + assert Ellipse(None, 1, 1).center == Point(0, 0) + assert e1 == c1 + assert e1 != e2 + assert e1 != l1 + assert p4 in e1 + assert e1 in e1 + assert e2 in e2 + assert 1 not in e2 + assert p2 not in e2 + assert e1.area == pi + assert e2.area == pi/2 + assert e3.area == pi*y1*abs(y1) + assert c1.area == e1.area + assert c1.circumference == e1.circumference + assert e3.circumference == 2*pi*y1 + assert e1.plot_interval() == e2.plot_interval() == [t, -pi, pi] + assert e1.plot_interval(x) == e2.plot_interval(x) == [x, -pi, pi] + + assert c1.minor == 1 + assert c1.major == 1 + assert c1.hradius == 1 + assert c1.vradius == 1 + + assert Ellipse((1, 1), 0, 0) == Point(1, 1) + assert Ellipse((1, 1), 1, 0) == Segment(Point(0, 1), Point(2, 1)) + assert Ellipse((1, 1), 0, 1) == Segment(Point(1, 0), Point(1, 2)) + + # Private Functions + assert hash(c1) == hash(Circle(Point(1, 0), Point(0, 1), Point(0, -1))) + assert c1 in e1 + assert (Line(p1, p2) in e1) is False + assert e1.__cmp__(e1) == 0 + assert e1.__cmp__(Point(0, 0)) > 0 + + # Encloses + assert e1.encloses(Segment(Point(-0.5, -0.5), Point(0.5, 0.5))) is True + assert e1.encloses(Line(p1, p2)) is False + assert e1.encloses(Ray(p1, p2)) is False + assert e1.encloses(e1) is False + assert e1.encloses( + Polygon(Point(-0.5, -0.5), Point(-0.5, 0.5), Point(0.5, 0.5))) is True + assert e1.encloses(RegularPolygon(p1, 0.5, 3)) is True + assert e1.encloses(RegularPolygon(p1, 5, 3)) is False + assert e1.encloses(RegularPolygon(p2, 5, 3)) is False + + assert e2.arbitrary_point() in e2 + raises(ValueError, lambda: Ellipse(Point(x, y), 1, 1).arbitrary_point(parameter='x')) + + # Foci + f1, f2 = Point(sqrt(12), 0), Point(-sqrt(12), 0) + ef = Ellipse(Point(0, 0), 4, 2) + assert ef.foci in [(f1, f2), (f2, f1)] + + # Tangents + v = sqrt(2) / 2 + p1_1 = Point(v, v) + p1_2 = p2 + Point(half, 0) + p1_3 = p2 + Point(0, 1) + assert e1.tangent_lines(p4) == c1.tangent_lines(p4) + assert e2.tangent_lines(p1_2) == [Line(Point(Rational(3, 2), 1), Point(Rational(3, 2), S.Half))] + assert e2.tangent_lines(p1_3) == [Line(Point(1, 2), Point(Rational(5, 4), 2))] + assert c1.tangent_lines(p1_1) != [Line(p1_1, Point(0, sqrt(2)))] + assert c1.tangent_lines(p1) == [] + assert e2.is_tangent(Line(p1_2, p2 + Point(half, 1))) + assert e2.is_tangent(Line(p1_3, p2 + Point(half, 1))) + assert c1.is_tangent(Line(p1_1, Point(0, sqrt(2)))) + assert e1.is_tangent(Line(Point(0, 0), Point(1, 1))) is False + assert c1.is_tangent(e1) is True + assert c1.is_tangent(Ellipse(Point(2, 0), 1, 1)) is True + assert c1.is_tangent( + Polygon(Point(1, 1), Point(1, -1), Point(2, 0))) is False + assert c1.is_tangent( + Polygon(Point(1, 1), Point(1, 0), Point(2, 0))) is False + assert Circle(Point(5, 5), 3).is_tangent(Circle(Point(0, 5), 1)) is False + + assert Ellipse(Point(5, 5), 2, 1).tangent_lines(Point(0, 0)) == \ + [Line(Point(0, 0), Point(Rational(77, 25), Rational(132, 25))), + Line(Point(0, 0), Point(Rational(33, 5), Rational(22, 5)))] + assert Ellipse(Point(5, 5), 2, 1).tangent_lines(Point(3, 4)) == \ + [Line(Point(3, 4), Point(4, 4)), Line(Point(3, 4), Point(3, 5))] + assert Circle(Point(5, 5), 2).tangent_lines(Point(3, 3)) == \ + [Line(Point(3, 3), Point(4, 3)), Line(Point(3, 3), Point(3, 4))] + assert Circle(Point(5, 5), 2).tangent_lines(Point(5 - 2*sqrt(2), 5)) == \ + [Line(Point(5 - 2*sqrt(2), 5), Point(5 - sqrt(2), 5 - sqrt(2))), + Line(Point(5 - 2*sqrt(2), 5), Point(5 - sqrt(2), 5 + sqrt(2))), ] + assert Circle(Point(5, 5), 5).tangent_lines(Point(4, 0)) == \ + [Line(Point(4, 0), Point(Rational(40, 13), Rational(5, 13))), + Line(Point(4, 0), Point(5, 0))] + assert Circle(Point(5, 5), 5).tangent_lines(Point(0, 6)) == \ + [Line(Point(0, 6), Point(0, 7)), + Line(Point(0, 6), Point(Rational(5, 13), Rational(90, 13)))] + + # for numerical calculations, we shouldn't demand exact equality, + # so only test up to the desired precision + def lines_close(l1, l2, prec): + """ tests whether l1 and 12 are within 10**(-prec) + of each other """ + return abs(l1.p1 - l2.p1) < 10**(-prec) and abs(l1.p2 - l2.p2) < 10**(-prec) + def line_list_close(ll1, ll2, prec): + return all(lines_close(l1, l2, prec) for l1, l2 in zip(ll1, ll2)) + + e = Ellipse(Point(0, 0), 2, 1) + assert e.normal_lines(Point(0, 0)) == \ + [Line(Point(0, 0), Point(0, 1)), Line(Point(0, 0), Point(1, 0))] + assert e.normal_lines(Point(1, 0)) == \ + [Line(Point(0, 0), Point(1, 0))] + assert e.normal_lines((0, 1)) == \ + [Line(Point(0, 0), Point(0, 1))] + assert line_list_close(e.normal_lines(Point(1, 1), 2), [ + Line(Point(Rational(-51, 26), Rational(-1, 5)), Point(Rational(-25, 26), Rational(17, 83))), + Line(Point(Rational(28, 29), Rational(-7, 8)), Point(Rational(57, 29), Rational(-9, 2)))], 2) + # test the failure of Poly.intervals and checks a point on the boundary + p = Point(sqrt(3), S.Half) + assert p in e + assert line_list_close(e.normal_lines(p, 2), [ + Line(Point(Rational(-341, 171), Rational(-1, 13)), Point(Rational(-170, 171), Rational(5, 64))), + Line(Point(Rational(26, 15), Rational(-1, 2)), Point(Rational(41, 15), Rational(-43, 26)))], 2) + # be sure to use the slope that isn't undefined on boundary + e = Ellipse((0, 0), 2, 2*sqrt(3)/3) + assert line_list_close(e.normal_lines((1, 1), 2), [ + Line(Point(Rational(-64, 33), Rational(-20, 71)), Point(Rational(-31, 33), Rational(2, 13))), + Line(Point(1, -1), Point(2, -4))], 2) + # general ellipse fails except under certain conditions + e = Ellipse((0, 0), x, 1) + assert e.normal_lines((x + 1, 0)) == [Line(Point(0, 0), Point(1, 0))] + raises(NotImplementedError, lambda: e.normal_lines((x + 1, 1))) + # Properties + major = 3 + minor = 1 + e4 = Ellipse(p2, minor, major) + assert e4.focus_distance == sqrt(major**2 - minor**2) + ecc = e4.focus_distance / major + assert e4.eccentricity == ecc + assert e4.periapsis == major*(1 - ecc) + assert e4.apoapsis == major*(1 + ecc) + assert e4.semilatus_rectum == major*(1 - ecc ** 2) + # independent of orientation + e4 = Ellipse(p2, major, minor) + assert e4.focus_distance == sqrt(major**2 - minor**2) + ecc = e4.focus_distance / major + assert e4.eccentricity == ecc + assert e4.periapsis == major*(1 - ecc) + assert e4.apoapsis == major*(1 + ecc) + + # Intersection + l1 = Line(Point(1, -5), Point(1, 5)) + l2 = Line(Point(-5, -1), Point(5, -1)) + l3 = Line(Point(-1, -1), Point(1, 1)) + l4 = Line(Point(-10, 0), Point(0, 10)) + pts_c1_l3 = [Point(sqrt(2)/2, sqrt(2)/2), Point(-sqrt(2)/2, -sqrt(2)/2)] + + assert intersection(e2, l4) == [] + assert intersection(c1, Point(1, 0)) == [Point(1, 0)] + assert intersection(c1, l1) == [Point(1, 0)] + assert intersection(c1, l2) == [Point(0, -1)] + assert intersection(c1, l3) in [pts_c1_l3, [pts_c1_l3[1], pts_c1_l3[0]]] + assert intersection(c1, c2) == [Point(0, 1), Point(1, 0)] + assert intersection(c1, c3) == [Point(sqrt(2)/2, sqrt(2)/2)] + assert e1.intersection(l1) == [Point(1, 0)] + assert e2.intersection(l4) == [] + assert e1.intersection(Circle(Point(0, 2), 1)) == [Point(0, 1)] + assert e1.intersection(Circle(Point(5, 0), 1)) == [] + assert e1.intersection(Ellipse(Point(2, 0), 1, 1)) == [Point(1, 0)] + assert e1.intersection(Ellipse(Point(5, 0), 1, 1)) == [] + assert e1.intersection(Point(2, 0)) == [] + assert e1.intersection(e1) == e1 + assert intersection(Ellipse(Point(0, 0), 2, 1), Ellipse(Point(3, 0), 1, 2)) == [Point(2, 0)] + assert intersection(Circle(Point(0, 0), 2), Circle(Point(3, 0), 1)) == [Point(2, 0)] + assert intersection(Circle(Point(0, 0), 2), Circle(Point(7, 0), 1)) == [] + assert intersection(Ellipse(Point(0, 0), 5, 17), Ellipse(Point(4, 0), 1, 0.2) + ) == [Point(5.0, 0, evaluate=False)] + assert intersection(Ellipse(Point(0, 0), 5, 17), Ellipse(Point(4, 0), 0.999, 0.2)) == [] + assert Circle((0, 0), S.Half).intersection( + Triangle((-1, 0), (1, 0), (0, 1))) == [ + Point(Rational(-1, 2), 0), Point(S.Half, 0)] + raises(TypeError, lambda: intersection(e2, Line((0, 0, 0), (0, 0, 1)))) + raises(TypeError, lambda: intersection(e2, Rational(12))) + raises(TypeError, lambda: Ellipse.intersection(e2, 1)) + # some special case intersections + csmall = Circle(p1, 3) + cbig = Circle(p1, 5) + cout = Circle(Point(5, 5), 1) + # one circle inside of another + assert csmall.intersection(cbig) == [] + # separate circles + assert csmall.intersection(cout) == [] + # coincident circles + assert csmall.intersection(csmall) == csmall + + v = sqrt(2) + t1 = Triangle(Point(0, v), Point(0, -v), Point(v, 0)) + points = intersection(t1, c1) + assert len(points) == 4 + assert Point(0, 1) in points + assert Point(0, -1) in points + assert Point(v/2, v/2) in points + assert Point(v/2, -v/2) in points + + circ = Circle(Point(0, 0), 5) + elip = Ellipse(Point(0, 0), 5, 20) + assert intersection(circ, elip) in \ + [[Point(5, 0), Point(-5, 0)], [Point(-5, 0), Point(5, 0)]] + assert elip.tangent_lines(Point(0, 0)) == [] + elip = Ellipse(Point(0, 0), 3, 2) + assert elip.tangent_lines(Point(3, 0)) == \ + [Line(Point(3, 0), Point(3, -12))] + + e1 = Ellipse(Point(0, 0), 5, 10) + e2 = Ellipse(Point(2, 1), 4, 8) + a = Rational(53, 17) + c = 2*sqrt(3991)/17 + ans = [Point(a - c/8, a/2 + c), Point(a + c/8, a/2 - c)] + assert e1.intersection(e2) == ans + e2 = Ellipse(Point(x, y), 4, 8) + c = sqrt(3991) + ans = [Point(-c/68 + a, c*Rational(2, 17) + a/2), Point(c/68 + a, c*Rational(-2, 17) + a/2)] + assert [p.subs({x: 2, y:1}) for p in e1.intersection(e2)] == ans + + # Combinations of above + assert e3.is_tangent(e3.tangent_lines(p1 + Point(y1, 0))[0]) + + e = Ellipse((1, 2), 3, 2) + assert e.tangent_lines(Point(10, 0)) == \ + [Line(Point(10, 0), Point(1, 0)), + Line(Point(10, 0), Point(Rational(14, 5), Rational(18, 5)))] + + # encloses_point + e = Ellipse((0, 0), 1, 2) + assert e.encloses_point(e.center) + assert e.encloses_point(e.center + Point(0, e.vradius - Rational(1, 10))) + assert e.encloses_point(e.center + Point(e.hradius - Rational(1, 10), 0)) + assert e.encloses_point(e.center + Point(e.hradius, 0)) is False + assert e.encloses_point( + e.center + Point(e.hradius + Rational(1, 10), 0)) is False + e = Ellipse((0, 0), 2, 1) + assert e.encloses_point(e.center) + assert e.encloses_point(e.center + Point(0, e.vradius - Rational(1, 10))) + assert e.encloses_point(e.center + Point(e.hradius - Rational(1, 10), 0)) + assert e.encloses_point(e.center + Point(e.hradius, 0)) is False + assert e.encloses_point( + e.center + Point(e.hradius + Rational(1, 10), 0)) is False + assert c1.encloses_point(Point(1, 0)) is False + assert c1.encloses_point(Point(0.3, 0.4)) is True + + assert e.scale(2, 3) == Ellipse((0, 0), 4, 3) + assert e.scale(3, 6) == Ellipse((0, 0), 6, 6) + assert e.rotate(pi) == e + assert e.rotate(pi, (1, 2)) == Ellipse(Point(2, 4), 2, 1) + raises(NotImplementedError, lambda: e.rotate(pi/3)) + + # Circle rotation tests (Issue #11743) + # Link - https://github.com/sympy/sympy/issues/11743 + cir = Circle(Point(1, 0), 1) + assert cir.rotate(pi/2) == Circle(Point(0, 1), 1) + assert cir.rotate(pi/3) == Circle(Point(S.Half, sqrt(3)/2), 1) + assert cir.rotate(pi/3, Point(1, 0)) == Circle(Point(1, 0), 1) + assert cir.rotate(pi/3, Point(0, 1)) == Circle(Point(S.Half + sqrt(3)/2, S.Half + sqrt(3)/2), 1) + + +def test_construction(): + e1 = Ellipse(hradius=2, vradius=1, eccentricity=None) + assert e1.eccentricity == sqrt(3)/2 + + e2 = Ellipse(hradius=2, vradius=None, eccentricity=sqrt(3)/2) + assert e2.vradius == 1 + + e3 = Ellipse(hradius=None, vradius=1, eccentricity=sqrt(3)/2) + assert e3.hradius == 2 + + # filter(None, iterator) filters out anything falsey, including 0 + # eccentricity would be filtered out in this case and the constructor would throw an error + e4 = Ellipse(Point(0, 0), hradius=1, eccentricity=0) + assert e4.vradius == 1 + + #tests for eccentricity > 1 + raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity = S(3)/2)) + raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity=sec(5))) + raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity=S.Pi-S(2))) + + #tests for eccentricity = 1 + #if vradius is not defined + assert Ellipse(None, 1, None, 1).length == 2 + #if hradius is not defined + raises(GeometryError, lambda: Ellipse(None, None, 1, eccentricity = 1)) + + #tests for eccentricity < 0 + raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity = -3)) + raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity = -0.5)) + +def test_ellipse_random_point(): + y1 = Symbol('y1', real=True) + e3 = Ellipse(Point(0, 0), y1, y1) + rx, ry = Symbol('rx'), Symbol('ry') + for ind in range(0, 5): + r = e3.random_point() + # substitution should give zero*y1**2 + assert e3.equation(rx, ry).subs(zip((rx, ry), r.args)).equals(0) + # test for the case with seed + r = e3.random_point(seed=1) + assert e3.equation(rx, ry).subs(zip((rx, ry), r.args)).equals(0) + + +def test_repr(): + assert repr(Circle((0, 1), 2)) == 'Circle(Point2D(0, 1), 2)' + + +def test_transform(): + c = Circle((1, 1), 2) + assert c.scale(-1) == Circle((-1, 1), 2) + assert c.scale(y=-1) == Circle((1, -1), 2) + assert c.scale(2) == Ellipse((2, 1), 4, 2) + + assert Ellipse((0, 0), 2, 3).scale(2, 3, (4, 5)) == \ + Ellipse(Point(-4, -10), 4, 9) + assert Circle((0, 0), 2).scale(2, 3, (4, 5)) == \ + Ellipse(Point(-4, -10), 4, 6) + assert Ellipse((0, 0), 2, 3).scale(3, 3, (4, 5)) == \ + Ellipse(Point(-8, -10), 6, 9) + assert Circle((0, 0), 2).scale(3, 3, (4, 5)) == \ + Circle(Point(-8, -10), 6) + assert Circle(Point(-8, -10), 6).scale(Rational(1, 3), Rational(1, 3), (4, 5)) == \ + Circle((0, 0), 2) + assert Circle((0, 0), 2).translate(4, 5) == \ + Circle((4, 5), 2) + assert Circle((0, 0), 2).scale(3, 3) == \ + Circle((0, 0), 6) + + +def test_bounds(): + e1 = Ellipse(Point(0, 0), 3, 5) + e2 = Ellipse(Point(2, -2), 7, 7) + c1 = Circle(Point(2, -2), 7) + c2 = Circle(Point(-2, 0), Point(0, 2), Point(2, 0)) + assert e1.bounds == (-3, -5, 3, 5) + assert e2.bounds == (-5, -9, 9, 5) + assert c1.bounds == (-5, -9, 9, 5) + assert c2.bounds == (-2, -2, 2, 2) + + +def test_reflect(): + b = Symbol('b') + m = Symbol('m') + l = Line((0, b), slope=m) + t1 = Triangle((0, 0), (1, 0), (2, 3)) + assert t1.area == -t1.reflect(l).area + e = Ellipse((1, 0), 1, 2) + assert e.area == -e.reflect(Line((1, 0), slope=0)).area + assert e.area == -e.reflect(Line((1, 0), slope=oo)).area + raises(NotImplementedError, lambda: e.reflect(Line((1, 0), slope=m))) + assert Circle((0, 1), 1).reflect(Line((0, 0), (1, 1))) == Circle(Point2D(1, 0), -1) + + +def test_is_tangent(): + e1 = Ellipse(Point(0, 0), 3, 5) + c1 = Circle(Point(2, -2), 7) + assert e1.is_tangent(Point(0, 0)) is False + assert e1.is_tangent(Point(3, 0)) is False + assert e1.is_tangent(e1) is True + assert e1.is_tangent(Ellipse((0, 0), 1, 2)) is False + assert e1.is_tangent(Ellipse((0, 0), 3, 2)) is True + assert c1.is_tangent(Ellipse((2, -2), 7, 1)) is True + assert c1.is_tangent(Circle((11, -2), 2)) is True + assert c1.is_tangent(Circle((7, -2), 2)) is True + assert c1.is_tangent(Ray((-5, -2), (-15, -20))) is False + assert c1.is_tangent(Ray((-3, -2), (-15, -20))) is False + assert c1.is_tangent(Ray((-3, -22), (15, 20))) is False + assert c1.is_tangent(Ray((9, 20), (9, -20))) is True + assert c1.is_tangent(Ray((2, 5), (9, 5))) is True + assert c1.is_tangent(Segment((2, 5), (9, 5))) is True + assert e1.is_tangent(Segment((2, 2), (-7, 7))) is False + assert e1.is_tangent(Segment((0, 0), (1, 2))) is False + assert c1.is_tangent(Segment((0, 0), (-5, -2))) is False + assert e1.is_tangent(Segment((3, 0), (12, 12))) is False + assert e1.is_tangent(Segment((12, 12), (3, 0))) is False + assert e1.is_tangent(Segment((-3, 0), (3, 0))) is False + assert e1.is_tangent(Segment((-3, 5), (3, 5))) is True + assert e1.is_tangent(Line((10, 0), (10, 10))) is False + assert e1.is_tangent(Line((0, 0), (1, 1))) is False + assert e1.is_tangent(Line((-3, 0), (-2.99, -0.001))) is False + assert e1.is_tangent(Line((-3, 0), (-3, 1))) is True + assert e1.is_tangent(Polygon((0, 0), (5, 5), (5, -5))) is False + assert e1.is_tangent(Polygon((-100, -50), (-40, -334), (-70, -52))) is False + assert e1.is_tangent(Polygon((-3, 0), (3, 0), (0, 1))) is False + assert e1.is_tangent(Polygon((-3, 0), (3, 0), (0, 5))) is False + assert e1.is_tangent(Polygon((-3, 0), (0, -5), (3, 0), (0, 5))) is False + assert e1.is_tangent(Polygon((-3, -5), (-3, 5), (3, 5), (3, -5))) is True + assert c1.is_tangent(Polygon((-3, -5), (-3, 5), (3, 5), (3, -5))) is False + assert e1.is_tangent(Polygon((0, 0), (3, 0), (7, 7), (0, 5))) is False + assert e1.is_tangent(Polygon((3, 12), (3, -12), (6, 5))) is False + assert e1.is_tangent(Polygon((3, 12), (3, -12), (0, -5), (0, 5))) is False + assert e1.is_tangent(Polygon((3, 0), (5, 7), (6, -5))) is False + assert c1.is_tangent(Segment((0, 0), (-5, -2))) is False + assert e1.is_tangent(Segment((-3, 0), (3, 0))) is False + assert e1.is_tangent(Segment((-3, 5), (3, 5))) is True + assert e1.is_tangent(Polygon((0, 0), (5, 5), (5, -5))) is False + assert e1.is_tangent(Polygon((-100, -50), (-40, -334), (-70, -52))) is False + assert e1.is_tangent(Polygon((-3, -5), (-3, 5), (3, 5), (3, -5))) is True + assert c1.is_tangent(Polygon((-3, -5), (-3, 5), (3, 5), (3, -5))) is False + assert e1.is_tangent(Polygon((3, 12), (3, -12), (0, -5), (0, 5))) is False + assert e1.is_tangent(Polygon((3, 0), (5, 7), (6, -5))) is False + raises(TypeError, lambda: e1.is_tangent(Point(0, 0, 0))) + raises(TypeError, lambda: e1.is_tangent(Rational(5))) + + +def test_parameter_value(): + t = Symbol('t') + e = Ellipse(Point(0, 0), 3, 5) + assert e.parameter_value((3, 0), t) == {t: 0} + raises(ValueError, lambda: e.parameter_value((4, 0), t)) + + +@slow +def test_second_moment_of_area(): + x, y = symbols('x, y') + e = Ellipse(Point(0, 0), 5, 4) + I_yy = 2*4*integrate(sqrt(25 - x**2)*x**2, (x, -5, 5))/5 + I_xx = 2*5*integrate(sqrt(16 - y**2)*y**2, (y, -4, 4))/4 + Y = 3*sqrt(1 - x**2/5**2) + I_xy = integrate(integrate(y, (y, -Y, Y))*x, (x, -5, 5)) + assert I_yy == e.second_moment_of_area()[1] + assert I_xx == e.second_moment_of_area()[0] + assert I_xy == e.second_moment_of_area()[2] + #checking for other point + t1 = e.second_moment_of_area(Point(6,5)) + t2 = (580*pi, 845*pi, 600*pi) + assert t1==t2 + + +def test_section_modulus_and_polar_second_moment_of_area(): + d = Symbol('d', positive=True) + c = Circle((3, 7), 8) + assert c.polar_second_moment_of_area() == 2048*pi + assert c.section_modulus() == (128*pi, 128*pi) + c = Circle((2, 9), d/2) + assert c.polar_second_moment_of_area() == pi*d**3*Abs(d)/64 + pi*d*Abs(d)**3/64 + assert c.section_modulus() == (pi*d**3/S(32), pi*d**3/S(32)) + + a, b = symbols('a, b', positive=True) + e = Ellipse((4, 6), a, b) + assert e.section_modulus() == (pi*a*b**2/S(4), pi*a**2*b/S(4)) + assert e.polar_second_moment_of_area() == pi*a**3*b/S(4) + pi*a*b**3/S(4) + e = e.rotate(pi/2) # no change in polar and section modulus + assert e.section_modulus() == (pi*a**2*b/S(4), pi*a*b**2/S(4)) + assert e.polar_second_moment_of_area() == pi*a**3*b/S(4) + pi*a*b**3/S(4) + + e = Ellipse((a, b), 2, 6) + assert e.section_modulus() == (18*pi, 6*pi) + assert e.polar_second_moment_of_area() == 120*pi + + e = Ellipse(Point(0, 0), 2, 2) + assert e.section_modulus() == (2*pi, 2*pi) + assert e.section_modulus(Point(2, 2)) == (2*pi, 2*pi) + assert e.section_modulus((2, 2)) == (2*pi, 2*pi) + + +def test_circumference(): + M = Symbol('M') + m = Symbol('m') + assert Ellipse(Point(0, 0), M, m).circumference == 4 * M * elliptic_e((M ** 2 - m ** 2) / M**2) + + assert Ellipse(Point(0, 0), 5, 4).circumference == 20 * elliptic_e(S(9) / 25) + + # circle + assert Ellipse(None, 1, None, 0).circumference == 2*pi + + # test numerically + assert abs(Ellipse(None, hradius=5, vradius=3).circumference.evalf(16) - 25.52699886339813) < 1e-10 + + +def test_issue_15259(): + assert Circle((1, 2), 0) == Point(1, 2) + + +def test_issue_15797_equals(): + Ri = 0.024127189424130748 + Ci = (0.0864931002830291, 0.0819863295239654) + A = Point(0, 0.0578591400998346) + c = Circle(Ci, Ri) # evaluated + assert c.is_tangent(c.tangent_lines(A)[0]) == True + assert c.center.x.is_Rational + assert c.center.y.is_Rational + assert c.radius.is_Rational + u = Circle(Ci, Ri, evaluate=False) # unevaluated + assert u.center.x.is_Float + assert u.center.y.is_Float + assert u.radius.is_Float + + +def test_auxiliary_circle(): + x, y, a, b = symbols('x y a b') + e = Ellipse((x, y), a, b) + # the general result + assert e.auxiliary_circle() == Circle((x, y), Max(a, b)) + # a special case where Ellipse is a Circle + assert Circle((3, 4), 8).auxiliary_circle() == Circle((3, 4), 8) + + +def test_director_circle(): + x, y, a, b = symbols('x y a b') + e = Ellipse((x, y), a, b) + # the general result + assert e.director_circle() == Circle((x, y), sqrt(a**2 + b**2)) + # a special case where Ellipse is a Circle + assert Circle((3, 4), 8).director_circle() == Circle((3, 4), 8*sqrt(2)) + + +def test_evolute(): + #ellipse centered at h,k + x, y, h, k = symbols('x y h k',real = True) + a, b = symbols('a b') + e = Ellipse(Point(h, k), a, b) + t1 = (e.hradius*(x - e.center.x))**Rational(2, 3) + t2 = (e.vradius*(y - e.center.y))**Rational(2, 3) + E = t1 + t2 - (e.hradius**2 - e.vradius**2)**Rational(2, 3) + assert e.evolute() == E + #Numerical Example + e = Ellipse(Point(1, 1), 6, 3) + t1 = (6*(x - 1))**Rational(2, 3) + t2 = (3*(y - 1))**Rational(2, 3) + E = t1 + t2 - (27)**Rational(2, 3) + assert e.evolute() == E + + +def test_svg(): + e1 = Ellipse(Point(1, 0), 3, 2) + assert e1._svg(2, "#FFAAFF") == '' diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_entity.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_entity.py new file mode 100644 index 0000000000000000000000000000000000000000..0d440fd5dbd193c7c490b45a706fab2703e247ec --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_entity.py @@ -0,0 +1,120 @@ +from sympy.core.numbers import (Rational, pi) +from sympy.core.singleton import S +from sympy.core.symbol import Symbol +from sympy.geometry import (Circle, Ellipse, Point, Line, Parabola, + Polygon, Ray, RegularPolygon, Segment, Triangle, Plane, Curve) +from sympy.geometry.entity import scale, GeometryEntity +from sympy.testing.pytest import raises + + +def test_entity(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + + assert GeometryEntity(x, y) in GeometryEntity(x, y) + raises(NotImplementedError, lambda: Point(0, 0) in GeometryEntity(x, y)) + + assert GeometryEntity(x, y) == GeometryEntity(x, y) + assert GeometryEntity(x, y).equals(GeometryEntity(x, y)) + + c = Circle((0, 0), 5) + assert GeometryEntity.encloses(c, Point(0, 0)) + assert GeometryEntity.encloses(c, Segment((0, 0), (1, 1))) + assert GeometryEntity.encloses(c, Line((0, 0), (1, 1))) is False + assert GeometryEntity.encloses(c, Circle((0, 0), 4)) + assert GeometryEntity.encloses(c, Polygon(Point(0, 0), Point(1, 0), Point(0, 1))) + assert GeometryEntity.encloses(c, RegularPolygon(Point(8, 8), 1, 3)) is False + + +def test_svg(): + a = Symbol('a') + b = Symbol('b') + d = Symbol('d') + + entity = Circle(Point(a, b), d) + assert entity._repr_svg_() is None + + entity = Circle(Point(0, 0), S.Infinity) + assert entity._repr_svg_() is None + + +def test_subs(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + p = Point(x, 2) + q = Point(1, 1) + r = Point(3, 4) + for o in [p, + Segment(p, q), + Ray(p, q), + Line(p, q), + Triangle(p, q, r), + RegularPolygon(p, 3, 6), + Polygon(p, q, r, Point(5, 4)), + Circle(p, 3), + Ellipse(p, 3, 4)]: + assert 'y' in str(o.subs(x, y)) + assert p.subs({x: 1}) == Point(1, 2) + assert Point(1, 2).subs(Point(1, 2), Point(3, 4)) == Point(3, 4) + assert Point(1, 2).subs((1, 2), Point(3, 4)) == Point(3, 4) + assert Point(1, 2).subs(Point(1, 2), Point(3, 4)) == Point(3, 4) + assert Point(1, 2).subs({(1, 2)}) == Point(2, 2) + raises(ValueError, lambda: Point(1, 2).subs(1)) + raises(TypeError, lambda: Point(1, 1).subs((Point(1, 1), Point(1, + 2)), 1, 2)) + + +def test_transform(): + assert scale(1, 2, (3, 4)).tolist() == \ + [[1, 0, 0], [0, 2, 0], [0, -4, 1]] + + +def test_reflect_entity_overrides(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + b = Symbol('b') + m = Symbol('m') + l = Line((0, b), slope=m) + p = Point(x, y) + r = p.reflect(l) + c = Circle((x, y), 3) + cr = c.reflect(l) + assert cr == Circle(r, -3) + assert c.area == -cr.area + + pent = RegularPolygon((1, 2), 1, 5) + slope = S.ComplexInfinity + while slope is S.ComplexInfinity: + slope = Rational(*(x._random()/2).as_real_imag()) + l = Line(pent.vertices[1], slope=slope) + rpent = pent.reflect(l) + assert rpent.center == pent.center.reflect(l) + rvert = [i.reflect(l) for i in pent.vertices] + for v in rpent.vertices: + for i in range(len(rvert)): + ri = rvert[i] + if ri.equals(v): + rvert.remove(ri) + break + assert not rvert + assert pent.area.equals(-rpent.area) + + +def test_geometry_EvalfMixin(): + x = pi + t = Symbol('t') + for g in [ + Point(x, x), + Plane(Point(0, x, 0), (0, 0, x)), + Curve((x*t, x), (t, 0, x)), + Ellipse((x, x), x, -x), + Circle((x, x), x), + Line((0, x), (x, 0)), + Segment((0, x), (x, 0)), + Ray((0, x), (x, 0)), + Parabola((0, x), Line((-x, 0), (x, 0))), + Polygon((0, 0), (0, x), (x, 0), (x, x)), + RegularPolygon((0, x), x, 4, x), + Triangle((0, 0), (x, 0), (x, x)), + ]: + assert str(g).replace('pi', '3.1') == str(g.n(2)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_geometrysets.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_geometrysets.py new file mode 100644 index 0000000000000000000000000000000000000000..c52898b3c9ba4e9db80c244db3aebf88db2cc8b4 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_geometrysets.py @@ -0,0 +1,38 @@ +from sympy.core.numbers import Rational +from sympy.core.singleton import S +from sympy.geometry import Circle, Line, Point, Polygon, Segment +from sympy.sets import FiniteSet, Union, Intersection, EmptySet + + +def test_booleans(): + """ test basic unions and intersections """ + half = S.Half + + p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)]) + p5, p6, p7 = map(Point, [(3, 2), (1, -1), (0, 2)]) + l1 = Line(Point(0,0), Point(1,1)) + l2 = Line(Point(half, half), Point(5,5)) + l3 = Line(p2, p3) + l4 = Line(p3, p4) + poly1 = Polygon(p1, p2, p3, p4) + poly2 = Polygon(p5, p6, p7) + poly3 = Polygon(p1, p2, p5) + assert Union(l1, l2).equals(l1) + assert Intersection(l1, l2).equals(l1) + assert Intersection(l1, l4) == FiniteSet(Point(1,1)) + assert Intersection(Union(l1, l4), l3) == FiniteSet(Point(Rational(-1, 3), Rational(-1, 3)), Point(5, 1)) + assert Intersection(l1, FiniteSet(Point(7,-7))) == EmptySet + assert Intersection(Circle(Point(0,0), 3), Line(p1,p2)) == FiniteSet(Point(-3,0), Point(3,0)) + assert Intersection(l1, FiniteSet(p1)) == FiniteSet(p1) + assert Union(l1, FiniteSet(p1)) == l1 + + fs = FiniteSet(Point(Rational(1, 3), 1), Point(Rational(2, 3), 0), Point(Rational(9, 5), Rational(1, 5)), Point(Rational(7, 3), 1)) + # test the intersection of polygons + assert Intersection(poly1, poly2) == fs + # make sure if we union polygons with subsets, the subsets go away + assert Union(poly1, poly2, fs) == Union(poly1, poly2) + # make sure that if we union with a FiniteSet that isn't a subset, + # that the points in the intersection stop being listed + assert Union(poly1, FiniteSet(Point(0,0), Point(3,5))) == Union(poly1, FiniteSet(Point(3,5))) + # intersect two polygons that share an edge + assert Intersection(poly1, poly3) == Union(FiniteSet(Point(Rational(3, 2), 1), Point(2, 1)), Segment(Point(0, 0), Point(1, 0))) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_line.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_line.py new file mode 100644 index 0000000000000000000000000000000000000000..5158ec05ab414020fbbe2681a2658454dd15b6eb --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_line.py @@ -0,0 +1,861 @@ +from sympy.core.numbers import (Float, Rational, oo, pi) +from sympy.core.relational import Eq +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (acos, cos, sin) +from sympy.sets import EmptySet +from sympy.simplify.simplify import simplify +from sympy.functions.elementary.trigonometric import tan +from sympy.geometry import (Circle, GeometryError, Line, Point, Ray, + Segment, Triangle, intersection, Point3D, Line3D, Ray3D, Segment3D, + Point2D, Line2D, Plane) +from sympy.geometry.line import Undecidable +from sympy.geometry.polygon import _asa as asa +from sympy.utilities.iterables import cartes +from sympy.testing.pytest import raises, warns + + +x = Symbol('x', real=True) +y = Symbol('y', real=True) +z = Symbol('z', real=True) +k = Symbol('k', real=True) +x1 = Symbol('x1', real=True) +y1 = Symbol('y1', real=True) +t = Symbol('t', real=True) +a, b = symbols('a,b', real=True) +m = symbols('m', real=True) + + +def test_object_from_equation(): + from sympy.abc import x, y, a, b + assert Line(3*x + y + 18) == Line2D(Point2D(0, -18), Point2D(1, -21)) + assert Line(3*x + 5 * y + 1) == Line2D( + Point2D(0, Rational(-1, 5)), Point2D(1, Rational(-4, 5))) + assert Line(3*a + b + 18, x="a", y="b") == Line2D( + Point2D(0, -18), Point2D(1, -21)) + assert Line(3*x + y) == Line2D(Point2D(0, 0), Point2D(1, -3)) + assert Line(x + y) == Line2D(Point2D(0, 0), Point2D(1, -1)) + assert Line(Eq(3*a + b, -18), x="a", y=b) == Line2D( + Point2D(0, -18), Point2D(1, -21)) + # issue 22361 + assert Line(x - 1) == Line2D(Point2D(1, 0), Point2D(1, 1)) + assert Line(2*x - 2, y=x) == Line2D(Point2D(0, 1), Point2D(1, 1)) + assert Line(y) == Line2D(Point2D(0, 0), Point2D(1, 0)) + assert Line(2*y, x=y) == Line2D(Point2D(0, 0), Point2D(0, 1)) + assert Line(y, x=y) == Line2D(Point2D(0, 0), Point2D(0, 1)) + raises(ValueError, lambda: Line(x / y)) + raises(ValueError, lambda: Line(a / b, x='a', y='b')) + raises(ValueError, lambda: Line(y / x)) + raises(ValueError, lambda: Line(b / a, x='a', y='b')) + raises(ValueError, lambda: Line((x + 1)**2 + y)) + + +def feq(a, b): + """Test if two floating point values are 'equal'.""" + t_float = Float("1.0E-10") + return -t_float < a - b < t_float + + +def test_angle_between(): + a = Point(1, 2, 3, 4) + b = a.orthogonal_direction + o = a.origin + assert feq(Line.angle_between(Line(Point(0, 0), Point(1, 1)), + Line(Point(0, 0), Point(5, 0))).evalf(), pi.evalf() / 4) + assert Line(a, o).angle_between(Line(b, o)) == pi / 2 + z = Point3D(0, 0, 0) + assert Line3D.angle_between(Line3D(z, Point3D(1, 1, 1)), + Line3D(z, Point3D(5, 0, 0))) == acos(sqrt(3) / 3) + # direction of points is used to determine angle + assert Line3D.angle_between(Line3D(z, Point3D(1, 1, 1)), + Line3D(Point3D(5, 0, 0), z)) == acos(-sqrt(3) / 3) + + +def test_closing_angle(): + a = Ray((0, 0), angle=0) + b = Ray((1, 2), angle=pi/2) + assert a.closing_angle(b) == -pi/2 + assert b.closing_angle(a) == pi/2 + assert a.closing_angle(a) == 0 + + +def test_smallest_angle(): + a = Line(Point(1, 1), Point(1, 2)) + b = Line(Point(1, 1),Point(2, 3)) + assert a.smallest_angle_between(b) == acos(2*sqrt(5)/5) + + +def test_svg(): + a = Line(Point(1, 1),Point(1, 2)) + assert a._svg() == '' + a = Segment(Point(1, 0),Point(1, 1)) + assert a._svg() == '' + a = Ray(Point(2, 3), Point(3, 5)) + assert a._svg() == '' + + +def test_arbitrary_point(): + l1 = Line3D(Point3D(0, 0, 0), Point3D(1, 1, 1)) + l2 = Line(Point(x1, x1), Point(y1, y1)) + assert l2.arbitrary_point() in l2 + assert Ray((1, 1), angle=pi / 4).arbitrary_point() == \ + Point(t + 1, t + 1) + assert Segment((1, 1), (2, 3)).arbitrary_point() == Point(1 + t, 1 + 2 * t) + assert l1.perpendicular_segment(l1.arbitrary_point()) == l1.arbitrary_point() + assert Ray3D((1, 1, 1), direction_ratio=[1, 2, 3]).arbitrary_point() == \ + Point3D(t + 1, 2 * t + 1, 3 * t + 1) + assert Segment3D(Point3D(0, 0, 0), Point3D(1, 1, 1)).midpoint == \ + Point3D(S.Half, S.Half, S.Half) + assert Segment3D(Point3D(x1, x1, x1), Point3D(y1, y1, y1)).length == sqrt(3) * sqrt((x1 - y1) ** 2) + assert Segment3D((1, 1, 1), (2, 3, 4)).arbitrary_point() == \ + Point3D(t + 1, 2 * t + 1, 3 * t + 1) + raises(ValueError, (lambda: Line((x, 1), (2, 3)).arbitrary_point(x))) + + +def test_are_concurrent_2d(): + l1 = Line(Point(0, 0), Point(1, 1)) + l2 = Line(Point(x1, x1), Point(x1, 1 + x1)) + assert Line.are_concurrent(l1) is False + assert Line.are_concurrent(l1, l2) + assert Line.are_concurrent(l1, l1, l1, l2) + assert Line.are_concurrent(l1, l2, Line(Point(5, x1), Point(Rational(-3, 5), x1))) + assert Line.are_concurrent(l1, Line(Point(0, 0), Point(-x1, x1)), l2) is False + + +def test_are_concurrent_3d(): + p1 = Point3D(0, 0, 0) + l1 = Line(p1, Point3D(1, 1, 1)) + parallel_1 = Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0)) + parallel_2 = Line3D(Point3D(0, 1, 0), Point3D(1, 1, 0)) + assert Line3D.are_concurrent(l1) is False + assert Line3D.are_concurrent(l1, Line(Point3D(x1, x1, x1), Point3D(y1, y1, y1))) is False + assert Line3D.are_concurrent(l1, Line3D(p1, Point3D(x1, x1, x1)), + Line(Point3D(x1, x1, x1), Point3D(x1, 1 + x1, 1))) is True + assert Line3D.are_concurrent(parallel_1, parallel_2) is False + + +def test_arguments(): + """Functions accepting `Point` objects in `geometry` + should also accept tuples, lists, and generators and + automatically convert them to points.""" + from sympy.utilities.iterables import subsets + + singles2d = ((1, 2), [1, 3], Point(1, 5)) + doubles2d = subsets(singles2d, 2) + l2d = Line(Point2D(1, 2), Point2D(2, 3)) + singles3d = ((1, 2, 3), [1, 2, 4], Point(1, 2, 6)) + doubles3d = subsets(singles3d, 2) + l3d = Line(Point3D(1, 2, 3), Point3D(1, 1, 2)) + singles4d = ((1, 2, 3, 4), [1, 2, 3, 5], Point(1, 2, 3, 7)) + doubles4d = subsets(singles4d, 2) + l4d = Line(Point(1, 2, 3, 4), Point(2, 2, 2, 2)) + # test 2D + test_single = ['contains', 'distance', 'equals', 'parallel_line', 'perpendicular_line', 'perpendicular_segment', + 'projection', 'intersection'] + for p in doubles2d: + Line2D(*p) + for func in test_single: + for p in singles2d: + getattr(l2d, func)(p) + # test 3D + for p in doubles3d: + Line3D(*p) + for func in test_single: + for p in singles3d: + getattr(l3d, func)(p) + # test 4D + for p in doubles4d: + Line(*p) + for func in test_single: + for p in singles4d: + getattr(l4d, func)(p) + + +def test_basic_properties_2d(): + p1 = Point(0, 0) + p2 = Point(1, 1) + p10 = Point(2000, 2000) + p_r3 = Ray(p1, p2).random_point() + p_r4 = Ray(p2, p1).random_point() + + l1 = Line(p1, p2) + l3 = Line(Point(x1, x1), Point(x1, 1 + x1)) + l4 = Line(p1, Point(1, 0)) + + r1 = Ray(p1, Point(0, 1)) + r2 = Ray(Point(0, 1), p1) + + s1 = Segment(p1, p10) + p_s1 = s1.random_point() + + assert Line((1, 1), slope=1) == Line((1, 1), (2, 2)) + assert Line((1, 1), slope=oo) == Line((1, 1), (1, 2)) + assert Line((1, 1), slope=oo).bounds == (1, 1, 1, 2) + assert Line((1, 1), slope=-oo) == Line((1, 1), (1, 2)) + assert Line(p1, p2).scale(2, 1) == Line(p1, Point(2, 1)) + assert Line(p1, p2) == Line(p1, p2) + assert Line(p1, p2) != Line(p2, p1) + assert l1 != Line(Point(x1, x1), Point(y1, y1)) + assert l1 != l3 + assert Line(p1, p10) != Line(p10, p1) + assert Line(p1, p10) != p1 + assert p1 in l1 # is p1 on the line l1? + assert p1 not in l3 + assert s1 in Line(p1, p10) + assert Ray(Point(0, 0), Point(0, 1)) in Ray(Point(0, 0), Point(0, 2)) + assert Ray(Point(0, 0), Point(0, 2)) in Ray(Point(0, 0), Point(0, 1)) + assert Ray(Point(0, 0), Point(0, 2)).xdirection == S.Zero + assert Ray(Point(0, 0), Point(1, 2)).xdirection == S.Infinity + assert Ray(Point(0, 0), Point(-1, 2)).xdirection == S.NegativeInfinity + assert Ray(Point(0, 0), Point(2, 0)).ydirection == S.Zero + assert Ray(Point(0, 0), Point(2, 2)).ydirection == S.Infinity + assert Ray(Point(0, 0), Point(2, -2)).ydirection == S.NegativeInfinity + assert (r1 in s1) is False + assert Segment(p1, p2) in s1 + assert Ray(Point(x1, x1), Point(x1, 1 + x1)) != Ray(p1, Point(-1, 5)) + assert Segment(p1, p2).midpoint == Point(S.Half, S.Half) + assert Segment(p1, Point(-x1, x1)).length == sqrt(2 * (x1 ** 2)) + + assert l1.slope == 1 + assert l3.slope is oo + assert l4.slope == 0 + assert Line(p1, Point(0, 1)).slope is oo + assert Line(r1.source, r1.random_point()).slope == r1.slope + assert Line(r2.source, r2.random_point()).slope == r2.slope + assert Segment(Point(0, -1), Segment(p1, Point(0, 1)).random_point()).slope == Segment(p1, Point(0, 1)).slope + + assert l4.coefficients == (0, 1, 0) + assert Line((-x, x), (-x + 1, x - 1)).coefficients == (1, 1, 0) + assert Line(p1, Point(0, 1)).coefficients == (1, 0, 0) + # issue 7963 + r = Ray((0, 0), angle=x) + assert r.subs(x, 3 * pi / 4) == Ray((0, 0), (-1, 1)) + assert r.subs(x, 5 * pi / 4) == Ray((0, 0), (-1, -1)) + assert r.subs(x, -pi / 4) == Ray((0, 0), (1, -1)) + assert r.subs(x, pi / 2) == Ray((0, 0), (0, 1)) + assert r.subs(x, -pi / 2) == Ray((0, 0), (0, -1)) + + for ind in range(0, 5): + assert l3.random_point() in l3 + + assert p_r3.x >= p1.x and p_r3.y >= p1.y + assert p_r4.x <= p2.x and p_r4.y <= p2.y + assert p1.x <= p_s1.x <= p10.x and p1.y <= p_s1.y <= p10.y + assert hash(s1) != hash(Segment(p10, p1)) + + assert s1.plot_interval() == [t, 0, 1] + assert Line(p1, p10).plot_interval() == [t, -5, 5] + assert Ray((0, 0), angle=pi / 4).plot_interval() == [t, 0, 10] + + +def test_basic_properties_3d(): + p1 = Point3D(0, 0, 0) + p2 = Point3D(1, 1, 1) + p3 = Point3D(x1, x1, x1) + p5 = Point3D(x1, 1 + x1, 1) + + l1 = Line3D(p1, p2) + l3 = Line3D(p3, p5) + + r1 = Ray3D(p1, Point3D(-1, 5, 0)) + r3 = Ray3D(p1, p2) + + s1 = Segment3D(p1, p2) + + assert Line3D((1, 1, 1), direction_ratio=[2, 3, 4]) == Line3D(Point3D(1, 1, 1), Point3D(3, 4, 5)) + assert Line3D((1, 1, 1), direction_ratio=[1, 5, 7]) == Line3D(Point3D(1, 1, 1), Point3D(2, 6, 8)) + assert Line3D((1, 1, 1), direction_ratio=[1, 2, 3]) == Line3D(Point3D(1, 1, 1), Point3D(2, 3, 4)) + assert Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0)).direction_cosine == [1, 0, 0] + assert Line3D(Line3D(p1, Point3D(0, 1, 0))) == Line3D(p1, Point3D(0, 1, 0)) + assert Ray3D(Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0))) == Ray3D(p1, Point3D(1, 0, 0)) + assert Line3D(p1, p2) != Line3D(p2, p1) + assert l1 != l3 + assert l1 != Line3D(p3, Point3D(y1, y1, y1)) + assert r3 != r1 + assert Ray3D(Point3D(0, 0, 0), Point3D(1, 1, 1)) in Ray3D(Point3D(0, 0, 0), Point3D(2, 2, 2)) + assert Ray3D(Point3D(0, 0, 0), Point3D(2, 2, 2)) in Ray3D(Point3D(0, 0, 0), Point3D(1, 1, 1)) + assert Ray3D(Point3D(0, 0, 0), Point3D(2, 2, 2)).xdirection == S.Infinity + assert Ray3D(Point3D(0, 0, 0), Point3D(2, 2, 2)).ydirection == S.Infinity + assert Ray3D(Point3D(0, 0, 0), Point3D(2, 2, 2)).zdirection == S.Infinity + assert Ray3D(Point3D(0, 0, 0), Point3D(-2, 2, 2)).xdirection == S.NegativeInfinity + assert Ray3D(Point3D(0, 0, 0), Point3D(2, -2, 2)).ydirection == S.NegativeInfinity + assert Ray3D(Point3D(0, 0, 0), Point3D(2, 2, -2)).zdirection == S.NegativeInfinity + assert Ray3D(Point3D(0, 0, 0), Point3D(0, 2, 2)).xdirection == S.Zero + assert Ray3D(Point3D(0, 0, 0), Point3D(2, 0, 2)).ydirection == S.Zero + assert Ray3D(Point3D(0, 0, 0), Point3D(2, 2, 0)).zdirection == S.Zero + assert p1 in l1 + assert p1 not in l3 + + assert l1.direction_ratio == [1, 1, 1] + + assert s1.midpoint == Point3D(S.Half, S.Half, S.Half) + # Test zdirection + assert Ray3D(p1, Point3D(0, 0, -1)).zdirection is S.NegativeInfinity + + +def test_contains(): + p1 = Point(0, 0) + + r = Ray(p1, Point(4, 4)) + r1 = Ray3D(p1, Point3D(0, 0, -1)) + r2 = Ray3D(p1, Point3D(0, 1, 0)) + r3 = Ray3D(p1, Point3D(0, 0, 1)) + + l = Line(Point(0, 1), Point(3, 4)) + # Segment contains + assert Point(0, (a + b) / 2) in Segment((0, a), (0, b)) + assert Point((a + b) / 2, 0) in Segment((a, 0), (b, 0)) + assert Point3D(0, 1, 0) in Segment3D((0, 1, 0), (0, 1, 0)) + assert Point3D(1, 0, 0) in Segment3D((1, 0, 0), (1, 0, 0)) + assert Segment3D(Point3D(0, 0, 0), Point3D(1, 0, 0)).contains([]) is True + assert Segment3D(Point3D(0, 0, 0), Point3D(1, 0, 0)).contains( + Segment3D(Point3D(2, 2, 2), Point3D(3, 2, 2))) is False + # Line contains + assert l.contains(Point(0, 1)) is True + assert l.contains((0, 1)) is True + assert l.contains((0, 0)) is False + # Ray contains + assert r.contains(p1) is True + assert r.contains((1, 1)) is True + assert r.contains((1, 3)) is False + assert r.contains(Segment((1, 1), (2, 2))) is True + assert r.contains(Segment((1, 2), (2, 5))) is False + assert r.contains(Ray((2, 2), (3, 3))) is True + assert r.contains(Ray((2, 2), (3, 5))) is False + assert r1.contains(Segment3D(p1, Point3D(0, 0, -10))) is True + assert r1.contains(Segment3D(Point3D(1, 1, 1), Point3D(2, 2, 2))) is False + assert r2.contains(Point3D(0, 0, 0)) is True + assert r3.contains(Point3D(0, 0, 0)) is True + assert Ray3D(Point3D(1, 1, 1), Point3D(1, 0, 0)).contains([]) is False + assert Line3D((0, 0, 0), (x, y, z)).contains((2 * x, 2 * y, 2 * z)) + with warns(UserWarning, test_stacklevel=False): + assert Line3D(p1, Point3D(0, 1, 0)).contains(Point(1.0, 1.0)) is False + + with warns(UserWarning, test_stacklevel=False): + assert r3.contains(Point(1.0, 1.0)) is False + + +def test_contains_nonreal_symbols(): + u, v, w, z = symbols('u, v, w, z') + l = Segment(Point(u, w), Point(v, z)) + p = Point(u*Rational(2, 3) + v/3, w*Rational(2, 3) + z/3) + assert l.contains(p) + + +def test_distance_2d(): + p1 = Point(0, 0) + p2 = Point(1, 1) + half = S.Half + + s1 = Segment(Point(0, 0), Point(1, 1)) + s2 = Segment(Point(half, half), Point(1, 0)) + + r = Ray(p1, p2) + + assert s1.distance(Point(0, 0)) == 0 + assert s1.distance((0, 0)) == 0 + assert s2.distance(Point(0, 0)) == 2 ** half / 2 + assert s2.distance(Point(Rational(3) / 2, Rational(3) / 2)) == 2 ** half + assert Line(p1, p2).distance(Point(-1, 1)) == sqrt(2) + assert Line(p1, p2).distance(Point(1, -1)) == sqrt(2) + assert Line(p1, p2).distance(Point(2, 2)) == 0 + assert Line(p1, p2).distance((-1, 1)) == sqrt(2) + assert Line((0, 0), (0, 1)).distance(p1) == 0 + assert Line((0, 0), (0, 1)).distance(p2) == 1 + assert Line((0, 0), (1, 0)).distance(p1) == 0 + assert Line((0, 0), (1, 0)).distance(p2) == 1 + assert r.distance(Point(-1, -1)) == sqrt(2) + assert r.distance(Point(1, 1)) == 0 + assert r.distance(Point(-1, 1)) == sqrt(2) + assert Ray((1, 1), (2, 2)).distance(Point(1.5, 3)) == 3 * sqrt(2) / 4 + assert r.distance((1, 1)) == 0 + + +def test_dimension_normalization(): + with warns(UserWarning, test_stacklevel=False): + assert Ray((1, 1), (2, 1, 2)) == Ray((1, 1, 0), (2, 1, 2)) + + +def test_distance_3d(): + p1, p2 = Point3D(0, 0, 0), Point3D(1, 1, 1) + p3 = Point3D(Rational(3) / 2, Rational(3) / 2, Rational(3) / 2) + + s1 = Segment3D(Point3D(0, 0, 0), Point3D(1, 1, 1)) + s2 = Segment3D(Point3D(S.Half, S.Half, S.Half), Point3D(1, 0, 1)) + + r = Ray3D(p1, p2) + + assert s1.distance(p1) == 0 + assert s2.distance(p1) == sqrt(3) / 2 + assert s2.distance(p3) == 2 * sqrt(6) / 3 + assert s1.distance((0, 0, 0)) == 0 + assert s2.distance((0, 0, 0)) == sqrt(3) / 2 + assert s1.distance(p1) == 0 + assert s2.distance(p1) == sqrt(3) / 2 + assert s2.distance(p3) == 2 * sqrt(6) / 3 + assert s1.distance((0, 0, 0)) == 0 + assert s2.distance((0, 0, 0)) == sqrt(3) / 2 + # Line to point + assert Line3D(p1, p2).distance(Point3D(-1, 1, 1)) == 2 * sqrt(6) / 3 + assert Line3D(p1, p2).distance(Point3D(1, -1, 1)) == 2 * sqrt(6) / 3 + assert Line3D(p1, p2).distance(Point3D(2, 2, 2)) == 0 + assert Line3D(p1, p2).distance((2, 2, 2)) == 0 + assert Line3D(p1, p2).distance((1, -1, 1)) == 2 * sqrt(6) / 3 + assert Line3D((0, 0, 0), (0, 1, 0)).distance(p1) == 0 + assert Line3D((0, 0, 0), (0, 1, 0)).distance(p2) == sqrt(2) + assert Line3D((0, 0, 0), (1, 0, 0)).distance(p1) == 0 + assert Line3D((0, 0, 0), (1, 0, 0)).distance(p2) == sqrt(2) + # Line to line + assert Line3D((0, 0, 0), (1, 0, 0)).distance(Line3D((0, 0, 0), (0, 1, 2))) == 0 + assert Line3D((0, 0, 0), (1, 0, 0)).distance(Line3D((0, 0, 0), (1, 0, 0))) == 0 + assert Line3D((0, 0, 0), (1, 0, 0)).distance(Line3D((10, 0, 0), (10, 1, 2))) == 0 + assert Line3D((0, 0, 0), (1, 0, 0)).distance(Line3D((0, 1, 0), (0, 1, 1))) == 1 + # Line to plane + assert Line3D((0, 0, 0), (1, 0, 0)).distance(Plane((2, 0, 0), (0, 0, 1))) == 0 + assert Line3D((0, 0, 0), (1, 0, 0)).distance(Plane((0, 1, 0), (0, 1, 0))) == 1 + assert Line3D((0, 0, 0), (1, 0, 0)).distance(Plane((1, 1, 3), (1, 0, 0))) == 0 + # Ray to point + assert r.distance(Point3D(-1, -1, -1)) == sqrt(3) + assert r.distance(Point3D(1, 1, 1)) == 0 + assert r.distance((-1, -1, -1)) == sqrt(3) + assert r.distance((1, 1, 1)) == 0 + assert Ray3D((0, 0, 0), (1, 1, 2)).distance((-1, -1, 2)) == 4 * sqrt(3) / 3 + assert Ray3D((1, 1, 1), (2, 2, 2)).distance(Point3D(1.5, -3, -1)) == Rational(9) / 2 + assert Ray3D((1, 1, 1), (2, 2, 2)).distance(Point3D(1.5, 3, 1)) == sqrt(78) / 6 + + +def test_equals(): + p1 = Point(0, 0) + p2 = Point(1, 1) + + l1 = Line(p1, p2) + l2 = Line((0, 5), slope=m) + l3 = Line(Point(x1, x1), Point(x1, 1 + x1)) + + assert l1.perpendicular_line(p1.args).equals(Line(Point(0, 0), Point(1, -1))) + assert l1.perpendicular_line(p1).equals(Line(Point(0, 0), Point(1, -1))) + assert Line(Point(x1, x1), Point(y1, y1)).parallel_line(Point(-x1, x1)). \ + equals(Line(Point(-x1, x1), Point(-y1, 2 * x1 - y1))) + assert l3.parallel_line(p1.args).equals(Line(Point(0, 0), Point(0, -1))) + assert l3.parallel_line(p1).equals(Line(Point(0, 0), Point(0, -1))) + assert (l2.distance(Point(2, 3)) - 2 * abs(m + 1) / sqrt(m ** 2 + 1)).equals(0) + assert Line3D(p1, Point3D(0, 1, 0)).equals(Point(1.0, 1.0)) is False + assert Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0)).equals(Line3D(Point3D(-5, 0, 0), Point3D(-1, 0, 0))) is True + assert Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0)).equals(Line3D(p1, Point3D(0, 1, 0))) is False + assert Ray3D(p1, Point3D(0, 0, -1)).equals(Point(1.0, 1.0)) is False + assert Ray3D(p1, Point3D(0, 0, -1)).equals(Ray3D(p1, Point3D(0, 0, -1))) is True + assert Line3D((0, 0), (t, t)).perpendicular_line(Point(0, 1, 0)).equals( + Line3D(Point3D(0, 1, 0), Point3D(S.Half, S.Half, 0))) + assert Line3D((0, 0), (t, t)).perpendicular_segment(Point(0, 1, 0)).equals(Segment3D((0, 1), (S.Half, S.Half))) + assert Line3D(p1, Point3D(0, 1, 0)).equals(Point(1.0, 1.0)) is False + + +def test_equation(): + p1 = Point(0, 0) + p2 = Point(1, 1) + l1 = Line(p1, p2) + l3 = Line(Point(x1, x1), Point(x1, 1 + x1)) + + assert simplify(l1.equation()) in (x - y, y - x) + assert simplify(l3.equation()) in (x - x1, x1 - x) + assert simplify(l1.equation()) in (x - y, y - x) + assert simplify(l3.equation()) in (x - x1, x1 - x) + + assert Line(p1, Point(1, 0)).equation(x=x, y=y) == y + assert Line(p1, Point(0, 1)).equation() == x + assert Line(Point(2, 0), Point(2, 1)).equation() == x - 2 + assert Line(p2, Point(2, 1)).equation() == y - 1 + + assert Line3D(Point(x1, x1, x1), Point(y1, y1, y1) + ).equation() == (-x + y, -x + z) + assert Line3D(Point(1, 2, 3), Point(2, 3, 4) + ).equation() == (-x + y - 1, -x + z - 2) + assert Line3D(Point(1, 2, 3), Point(1, 3, 4) + ).equation() == (x - 1, -y + z - 1) + assert Line3D(Point(1, 2, 3), Point(2, 2, 4) + ).equation() == (y - 2, -x + z - 2) + assert Line3D(Point(1, 2, 3), Point(2, 3, 3) + ).equation() == (-x + y - 1, z - 3) + assert Line3D(Point(1, 2, 3), Point(1, 2, 4) + ).equation() == (x - 1, y - 2) + assert Line3D(Point(1, 2, 3), Point(1, 3, 3) + ).equation() == (x - 1, z - 3) + assert Line3D(Point(1, 2, 3), Point(2, 2, 3) + ).equation() == (y - 2, z - 3) + + +def test_intersection_2d(): + p1 = Point(0, 0) + p2 = Point(1, 1) + p3 = Point(x1, x1) + p4 = Point(y1, y1) + + l1 = Line(p1, p2) + l3 = Line(Point(0, 0), Point(3, 4)) + + r1 = Ray(Point(1, 1), Point(2, 2)) + r2 = Ray(Point(0, 0), Point(3, 4)) + r4 = Ray(p1, p2) + r6 = Ray(Point(0, 1), Point(1, 2)) + r7 = Ray(Point(0.5, 0.5), Point(1, 1)) + + s1 = Segment(p1, p2) + s2 = Segment(Point(0.25, 0.25), Point(0.5, 0.5)) + s3 = Segment(Point(0, 0), Point(3, 4)) + + assert intersection(l1, p1) == [p1] + assert intersection(l1, Point(x1, 1 + x1)) == [] + assert intersection(l1, Line(p3, p4)) in [[l1], [Line(p3, p4)]] + assert intersection(l1, l1.parallel_line(Point(x1, 1 + x1))) == [] + assert intersection(l3, l3) == [l3] + assert intersection(l3, r2) == [r2] + assert intersection(l3, s3) == [s3] + assert intersection(s3, l3) == [s3] + assert intersection(Segment(Point(-10, 10), Point(10, 10)), Segment(Point(-5, -5), Point(-5, 5))) == [] + assert intersection(r2, l3) == [r2] + assert intersection(r1, Ray(Point(2, 2), Point(0, 0))) == [Segment(Point(1, 1), Point(2, 2))] + assert intersection(r1, Ray(Point(1, 1), Point(-1, -1))) == [Point(1, 1)] + assert intersection(r1, Segment(Point(0, 0), Point(2, 2))) == [Segment(Point(1, 1), Point(2, 2))] + + assert r4.intersection(s2) == [s2] + assert r4.intersection(Segment(Point(2, 3), Point(3, 4))) == [] + assert r4.intersection(Segment(Point(-1, -1), Point(0.5, 0.5))) == [Segment(p1, Point(0.5, 0.5))] + assert r4.intersection(Ray(p2, p1)) == [s1] + assert Ray(p2, p1).intersection(r6) == [] + assert r4.intersection(r7) == r7.intersection(r4) == [r7] + assert Ray3D((0, 0), (3, 0)).intersection(Ray3D((1, 0), (3, 0))) == [Ray3D((1, 0), (3, 0))] + assert Ray3D((1, 0), (3, 0)).intersection(Ray3D((0, 0), (3, 0))) == [Ray3D((1, 0), (3, 0))] + assert Ray(Point(0, 0), Point(0, 4)).intersection(Ray(Point(0, 1), Point(0, -1))) == \ + [Segment(Point(0, 0), Point(0, 1))] + + assert Segment3D((0, 0), (3, 0)).intersection( + Segment3D((1, 0), (2, 0))) == [Segment3D((1, 0), (2, 0))] + assert Segment3D((1, 0), (2, 0)).intersection( + Segment3D((0, 0), (3, 0))) == [Segment3D((1, 0), (2, 0))] + assert Segment3D((0, 0), (3, 0)).intersection( + Segment3D((3, 0), (4, 0))) == [Point3D((3, 0))] + assert Segment3D((0, 0), (3, 0)).intersection( + Segment3D((2, 0), (5, 0))) == [Segment3D((2, 0), (3, 0))] + assert Segment3D((0, 0), (3, 0)).intersection( + Segment3D((-2, 0), (1, 0))) == [Segment3D((0, 0), (1, 0))] + assert Segment3D((0, 0), (3, 0)).intersection( + Segment3D((-2, 0), (0, 0))) == [Point3D(0, 0)] + assert s1.intersection(Segment(Point(1, 1), Point(2, 2))) == [Point(1, 1)] + assert s1.intersection(Segment(Point(0.5, 0.5), Point(1.5, 1.5))) == [Segment(Point(0.5, 0.5), p2)] + assert s1.intersection(Segment(Point(4, 4), Point(5, 5))) == [] + assert s1.intersection(Segment(Point(-1, -1), p1)) == [p1] + assert s1.intersection(Segment(Point(-1, -1), Point(0.5, 0.5))) == [Segment(p1, Point(0.5, 0.5))] + assert s1.intersection(Line(Point(1, 0), Point(2, 1))) == [] + assert s1.intersection(s2) == [s2] + assert s2.intersection(s1) == [s2] + + assert asa(120, 8, 52) == \ + Triangle( + Point(0, 0), + Point(8, 0), + Point(-4 * cos(19 * pi / 90) / sin(2 * pi / 45), + 4 * sqrt(3) * cos(19 * pi / 90) / sin(2 * pi / 45))) + assert Line((0, 0), (1, 1)).intersection(Ray((1, 0), (1, 2))) == [Point(1, 1)] + assert Line((0, 0), (1, 1)).intersection(Segment((1, 0), (1, 2))) == [Point(1, 1)] + assert Ray((0, 0), (1, 1)).intersection(Ray((1, 0), (1, 2))) == [Point(1, 1)] + assert Ray((0, 0), (1, 1)).intersection(Segment((1, 0), (1, 2))) == [Point(1, 1)] + assert Ray((0, 0), (10, 10)).contains(Segment((1, 1), (2, 2))) is True + assert Segment((1, 1), (2, 2)) in Line((0, 0), (10, 10)) + assert s1.intersection(Ray((1, 1), (4, 4))) == [Point(1, 1)] + + # This test is disabled because it hangs after rref changes which simplify + # intermediate results and return a different representation from when the + # test was written. + # # 16628 - this should be fast + # p0 = Point2D(Rational(249, 5), Rational(497999, 10000)) + # p1 = Point2D((-58977084786*sqrt(405639795226) + 2030690077184193 + + # 20112207807*sqrt(630547164901) + 99600*sqrt(255775022850776494562626)) + # /(2000*sqrt(255775022850776494562626) + 1991998000*sqrt(405639795226) + # + 1991998000*sqrt(630547164901) + 1622561172902000), + # (-498000*sqrt(255775022850776494562626) - 995999*sqrt(630547164901) + + # 90004251917891999 + + # 496005510002*sqrt(405639795226))/(10000*sqrt(255775022850776494562626) + # + 9959990000*sqrt(405639795226) + 9959990000*sqrt(630547164901) + + # 8112805864510000)) + # p2 = Point2D(Rational(497, 10), Rational(-497, 10)) + # p3 = Point2D(Rational(-497, 10), Rational(-497, 10)) + # l = Line(p0, p1) + # s = Segment(p2, p3) + # n = (-52673223862*sqrt(405639795226) - 15764156209307469 - + # 9803028531*sqrt(630547164901) + + # 33200*sqrt(255775022850776494562626)) + # d = sqrt(405639795226) + 315274080450 + 498000*sqrt( + # 630547164901) + sqrt(255775022850776494562626) + # assert intersection(l, s) == [ + # Point2D(n/d*Rational(3, 2000), Rational(-497, 10))] + + +def test_line_intersection(): + # see also test_issue_11238 in test_matrices.py + x0 = tan(pi*Rational(13, 45)) + x1 = sqrt(3) + x2 = x0**2 + x, y = [8*x0/(x0 + x1), (24*x0 - 8*x1*x2)/(x2 - 3)] + assert Line(Point(0, 0), Point(1, -sqrt(3))).contains(Point(x, y)) is True + + +def test_intersection_3d(): + p1 = Point3D(0, 0, 0) + p2 = Point3D(1, 1, 1) + + l1 = Line3D(p1, p2) + l2 = Line3D(Point3D(0, 0, 0), Point3D(3, 4, 0)) + + r1 = Ray3D(Point3D(1, 1, 1), Point3D(2, 2, 2)) + r2 = Ray3D(Point3D(0, 0, 0), Point3D(3, 4, 0)) + + s1 = Segment3D(Point3D(0, 0, 0), Point3D(3, 4, 0)) + + assert intersection(l1, p1) == [p1] + assert intersection(l1, Point3D(x1, 1 + x1, 1)) == [] + assert intersection(l1, l1.parallel_line(p1)) == [Line3D(Point3D(0, 0, 0), Point3D(1, 1, 1))] + assert intersection(l2, r2) == [r2] + assert intersection(l2, s1) == [s1] + assert intersection(r2, l2) == [r2] + assert intersection(r1, Ray3D(Point3D(1, 1, 1), Point3D(-1, -1, -1))) == [Point3D(1, 1, 1)] + assert intersection(r1, Segment3D(Point3D(0, 0, 0), Point3D(2, 2, 2))) == [ + Segment3D(Point3D(1, 1, 1), Point3D(2, 2, 2))] + assert intersection(Ray3D(Point3D(1, 0, 0), Point3D(-1, 0, 0)), Ray3D(Point3D(0, 1, 0), Point3D(0, -1, 0))) \ + == [Point3D(0, 0, 0)] + assert intersection(r1, Ray3D(Point3D(2, 2, 2), Point3D(0, 0, 0))) == \ + [Segment3D(Point3D(1, 1, 1), Point3D(2, 2, 2))] + assert intersection(s1, r2) == [s1] + + assert Line3D(Point3D(4, 0, 1), Point3D(0, 4, 1)).intersection(Line3D(Point3D(0, 0, 1), Point3D(4, 4, 1))) == \ + [Point3D(2, 2, 1)] + assert Line3D((0, 1, 2), (0, 2, 3)).intersection(Line3D((0, 1, 2), (0, 1, 1))) == [Point3D(0, 1, 2)] + assert Line3D((0, 0), (t, t)).intersection(Line3D((0, 1), (t, t))) == \ + [Point3D(t, t)] + + assert Ray3D(Point3D(0, 0, 0), Point3D(0, 4, 0)).intersection(Ray3D(Point3D(0, 1, 1), Point3D(0, -1, 1))) == [] + + +def test_is_parallel(): + p1 = Point3D(0, 0, 0) + p2 = Point3D(1, 1, 1) + p3 = Point3D(x1, x1, x1) + + l2 = Line(Point(x1, x1), Point(y1, y1)) + l2_1 = Line(Point(x1, x1), Point(x1, 1 + x1)) + + assert Line.is_parallel(Line(Point(0, 0), Point(1, 1)), l2) + assert Line.is_parallel(l2, Line(Point(x1, x1), Point(x1, 1 + x1))) is False + assert Line.is_parallel(l2, l2.parallel_line(Point(-x1, x1))) + assert Line.is_parallel(l2_1, l2_1.parallel_line(Point(0, 0))) + assert Line3D(p1, p2).is_parallel(Line3D(p1, p2)) # same as in 2D + assert Line3D(Point3D(4, 0, 1), Point3D(0, 4, 1)).is_parallel(Line3D(Point3D(0, 0, 1), Point3D(4, 4, 1))) is False + assert Line3D(p1, p2).parallel_line(p3) == Line3D(Point3D(x1, x1, x1), + Point3D(x1 + 1, x1 + 1, x1 + 1)) + assert Line3D(p1, p2).parallel_line(p3.args) == \ + Line3D(Point3D(x1, x1, x1), Point3D(x1 + 1, x1 + 1, x1 + 1)) + assert Line3D(Point3D(4, 0, 1), Point3D(0, 4, 1)).is_parallel(Line3D(Point3D(0, 0, 1), Point3D(4, 4, 1))) is False + + +def test_is_perpendicular(): + p1 = Point(0, 0) + p2 = Point(1, 1) + + l1 = Line(p1, p2) + l2 = Line(Point(x1, x1), Point(y1, y1)) + l1_1 = Line(p1, Point(-x1, x1)) + # 2D + assert Line.is_perpendicular(l1, l1_1) + assert Line.is_perpendicular(l1, l2) is False + p = l1.random_point() + assert l1.perpendicular_segment(p) == p + # 3D + assert Line3D.is_perpendicular(Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0)), + Line3D(Point3D(0, 0, 0), Point3D(0, 1, 0))) is True + assert Line3D.is_perpendicular(Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0)), + Line3D(Point3D(0, 1, 0), Point3D(1, 1, 0))) is False + assert Line3D.is_perpendicular(Line3D(Point3D(0, 0, 0), Point3D(1, 1, 1)), + Line3D(Point3D(x1, x1, x1), Point3D(y1, y1, y1))) is False + + +def test_is_similar(): + p1 = Point(2000, 2000) + p2 = p1.scale(2, 2) + + r1 = Ray3D(Point3D(1, 1, 1), Point3D(1, 0, 0)) + r2 = Ray(Point(0, 0), Point(0, 1)) + + s1 = Segment(Point(0, 0), p1) + + assert s1.is_similar(Segment(p1, p2)) + assert s1.is_similar(r2) is False + assert r1.is_similar(Line3D(Point3D(1, 1, 1), Point3D(1, 0, 0))) is True + assert r1.is_similar(Line3D(Point3D(0, 0, 0), Point3D(0, 1, 0))) is False + + +def test_length(): + s2 = Segment3D(Point3D(x1, x1, x1), Point3D(y1, y1, y1)) + assert Line(Point(0, 0), Point(1, 1)).length is oo + assert s2.length == sqrt(3) * sqrt((x1 - y1) ** 2) + assert Line3D(Point3D(0, 0, 0), Point3D(1, 1, 1)).length is oo + + +def test_projection(): + p1 = Point(0, 0) + p2 = Point3D(0, 0, 0) + p3 = Point(-x1, x1) + + l1 = Line(p1, Point(1, 1)) + l2 = Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0)) + l3 = Line3D(p2, Point3D(1, 1, 1)) + + r1 = Ray(Point(1, 1), Point(2, 2)) + + s1 = Segment(Point2D(0, 0), Point2D(0, 1)) + s2 = Segment(Point2D(1, 0), Point2D(2, 1/2)) + + assert Line(Point(x1, x1), Point(y1, y1)).projection(Point(y1, y1)) == Point(y1, y1) + assert Line(Point(x1, x1), Point(x1, 1 + x1)).projection(Point(1, 1)) == Point(x1, 1) + assert Segment(Point(-2, 2), Point(0, 4)).projection(r1) == Segment(Point(-1, 3), Point(0, 4)) + assert Segment(Point(0, 4), Point(-2, 2)).projection(r1) == Segment(Point(0, 4), Point(-1, 3)) + assert s2.projection(s1) == EmptySet + assert l1.projection(p3) == p1 + assert l1.projection(Ray(p1, Point(-1, 5))) == Ray(Point(0, 0), Point(2, 2)) + assert l1.projection(Ray(p1, Point(-1, 1))) == p1 + assert r1.projection(Ray(Point(1, 1), Point(-1, -1))) == Point(1, 1) + assert r1.projection(Ray(Point(0, 4), Point(-1, -5))) == Segment(Point(1, 1), Point(2, 2)) + assert r1.projection(Segment(Point(-1, 5), Point(-5, -10))) == Segment(Point(1, 1), Point(2, 2)) + assert r1.projection(Ray(Point(1, 1), Point(-1, -1))) == Point(1, 1) + assert r1.projection(Ray(Point(0, 4), Point(-1, -5))) == Segment(Point(1, 1), Point(2, 2)) + assert r1.projection(Segment(Point(-1, 5), Point(-5, -10))) == Segment(Point(1, 1), Point(2, 2)) + + assert l3.projection(Ray3D(p2, Point3D(-1, 5, 0))) == Ray3D(Point3D(0, 0, 0), Point3D(Rational(4, 3), Rational(4, 3), Rational(4, 3))) + assert l3.projection(Ray3D(p2, Point3D(-1, 1, 1))) == Ray3D(Point3D(0, 0, 0), Point3D(Rational(1, 3), Rational(1, 3), Rational(1, 3))) + assert l2.projection(Point3D(5, 5, 0)) == Point3D(5, 0) + assert l2.projection(Line3D(Point3D(0, 1, 0), Point3D(1, 1, 0))).equals(l2) + + +def test_perpendicular_line(): + # 3d - requires a particular orthogonal to be selected + p1, p2, p3 = Point(0, 0, 0), Point(2, 3, 4), Point(-2, 2, 0) + l = Line(p1, p2) + p = l.perpendicular_line(p3) + assert p.p1 == p3 + assert p.p2 in l + # 2d - does not require special selection + p1, p2, p3 = Point(0, 0), Point(2, 3), Point(-2, 2) + l = Line(p1, p2) + p = l.perpendicular_line(p3) + assert p.p1 == p3 + # p is directed from l to p3 + assert p.direction.unit == (p3 - l.projection(p3)).unit + + +def test_perpendicular_bisector(): + s1 = Segment(Point(0, 0), Point(1, 1)) + aline = Line(Point(S.Half, S.Half), Point(Rational(3, 2), Rational(-1, 2))) + on_line = Segment(Point(S.Half, S.Half), Point(Rational(3, 2), Rational(-1, 2))).midpoint + + assert s1.perpendicular_bisector().equals(aline) + assert s1.perpendicular_bisector(on_line).equals(Segment(s1.midpoint, on_line)) + assert s1.perpendicular_bisector(on_line + (1, 0)).equals(aline) + + +def test_raises(): + d, e = symbols('a,b', real=True) + s = Segment((d, 0), (e, 0)) + + raises(TypeError, lambda: Line((1, 1), 1)) + raises(ValueError, lambda: Line(Point(0, 0), Point(0, 0))) + raises(Undecidable, lambda: Point(2 * d, 0) in s) + raises(ValueError, lambda: Ray3D(Point(1.0, 1.0))) + raises(ValueError, lambda: Line3D(Point3D(0, 0, 0), Point3D(0, 0, 0))) + raises(TypeError, lambda: Line3D((1, 1), 1)) + raises(ValueError, lambda: Line3D(Point3D(0, 0, 0))) + raises(TypeError, lambda: Ray((1, 1), 1)) + raises(GeometryError, lambda: Line(Point(0, 0), Point(1, 0)) + .projection(Circle(Point(0, 0), 1))) + + +def test_ray_generation(): + assert Ray((1, 1), angle=pi / 4) == Ray((1, 1), (2, 2)) + assert Ray((1, 1), angle=pi / 2) == Ray((1, 1), (1, 2)) + assert Ray((1, 1), angle=-pi / 2) == Ray((1, 1), (1, 0)) + assert Ray((1, 1), angle=-3 * pi / 2) == Ray((1, 1), (1, 2)) + assert Ray((1, 1), angle=5 * pi / 2) == Ray((1, 1), (1, 2)) + assert Ray((1, 1), angle=5.0 * pi / 2) == Ray((1, 1), (1, 2)) + assert Ray((1, 1), angle=pi) == Ray((1, 1), (0, 1)) + assert Ray((1, 1), angle=3.0 * pi) == Ray((1, 1), (0, 1)) + assert Ray((1, 1), angle=4.0 * pi) == Ray((1, 1), (2, 1)) + assert Ray((1, 1), angle=0) == Ray((1, 1), (2, 1)) + assert Ray((1, 1), angle=4.05 * pi) == Ray(Point(1, 1), + Point(2, -sqrt(5) * sqrt(2 * sqrt(5) + 10) / 4 - sqrt( + 2 * sqrt(5) + 10) / 4 + 2 + sqrt(5))) + assert Ray((1, 1), angle=4.02 * pi) == Ray(Point(1, 1), + Point(2, 1 + tan(4.02 * pi))) + assert Ray((1, 1), angle=5) == Ray((1, 1), (2, 1 + tan(5))) + + assert Ray3D((1, 1, 1), direction_ratio=[4, 4, 4]) == Ray3D(Point3D(1, 1, 1), Point3D(5, 5, 5)) + assert Ray3D((1, 1, 1), direction_ratio=[1, 2, 3]) == Ray3D(Point3D(1, 1, 1), Point3D(2, 3, 4)) + assert Ray3D((1, 1, 1), direction_ratio=[1, 1, 1]) == Ray3D(Point3D(1, 1, 1), Point3D(2, 2, 2)) + + +def test_issue_7814(): + circle = Circle(Point(x, 0), y) + line = Line(Point(k, z), slope=0) + _s = sqrt((y - z)*(y + z)) + assert line.intersection(circle) == [Point2D(x + _s, z), Point2D(x - _s, z)] + + +def test_issue_2941(): + def _check(): + for f, g in cartes(*[(Line, Ray, Segment)] * 2): + l1 = f(a, b) + l2 = g(c, d) + assert l1.intersection(l2) == l2.intersection(l1) + # intersect at end point + c, d = (-2, -2), (-2, 0) + a, b = (0, 0), (1, 1) + _check() + # midline intersection + c, d = (-2, -3), (-2, 0) + _check() + + +def test_parameter_value(): + t = Symbol('t') + p1, p2 = Point(0, 1), Point(5, 6) + l = Line(p1, p2) + assert l.parameter_value((5, 6), t) == {t: 1} + raises(ValueError, lambda: l.parameter_value((0, 0), t)) + + +def test_bisectors(): + r1 = Line3D(Point3D(0, 0, 0), Point3D(1, 0, 0)) + r2 = Line3D(Point3D(0, 0, 0), Point3D(0, 1, 0)) + bisections = r1.bisectors(r2) + assert bisections == [Line3D(Point3D(0, 0, 0), Point3D(1, 1, 0)), + Line3D(Point3D(0, 0, 0), Point3D(1, -1, 0))] + ans = [Line3D(Point3D(0, 0, 0), Point3D(1, 0, 1)), + Line3D(Point3D(0, 0, 0), Point3D(-1, 0, 1))] + l1 = (0, 0, 0), (0, 0, 1) + l2 = (0, 0), (1, 0) + for a, b in cartes((Line, Segment, Ray), repeat=2): + assert a(*l1).bisectors(b(*l2)) == ans + + +def test_issue_8615(): + a = Line3D(Point3D(6, 5, 0), Point3D(6, -6, 0)) + b = Line3D(Point3D(6, -1, 19/10), Point3D(6, -1, 0)) + assert a.intersection(b) == [Point3D(6, -1, 0)] + + +def test_issue_12598(): + r1 = Ray(Point(0, 1), Point(0.98, 0.79).n(2)) + r2 = Ray(Point(0, 0), Point(0.71, 0.71).n(2)) + assert str(r1.intersection(r2)[0]) == 'Point2D(0.82, 0.82)' + l1 = Line((0, 0), (1, 1)) + l2 = Segment((-1, 1), (0, -1)).n(2) + assert str(l1.intersection(l2)[0]) == 'Point2D(-0.33, -0.33)' + l2 = Segment((-1, 1), (-1/2, 1/2)).n(2) + assert not l1.intersection(l2) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_parabola.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_parabola.py new file mode 100644 index 0000000000000000000000000000000000000000..2a683f26619952d93475aca9ebd3d47cfb3657a6 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_parabola.py @@ -0,0 +1,143 @@ +from sympy.core.numbers import (Rational, oo) +from sympy.core.singleton import S +from sympy.core.symbol import symbols +from sympy.functions.elementary.complexes import sign +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.geometry.ellipse import (Circle, Ellipse) +from sympy.geometry.line import (Line, Ray2D, Segment2D) +from sympy.geometry.parabola import Parabola +from sympy.geometry.point import (Point, Point2D) +from sympy.testing.pytest import raises + +from sympy.abc import x, y + +def test_parabola_geom(): + a, b = symbols('a b') + p1 = Point(0, 0) + p2 = Point(3, 7) + p3 = Point(0, 4) + p4 = Point(6, 0) + p5 = Point(a, a) + d1 = Line(Point(4, 0), Point(4, 9)) + d2 = Line(Point(7, 6), Point(3, 6)) + d3 = Line(Point(4, 0), slope=oo) + d4 = Line(Point(7, 6), slope=0) + d5 = Line(Point(b, a), slope=oo) + d6 = Line(Point(a, b), slope=0) + + half = S.Half + + pa1 = Parabola(None, d2) + pa2 = Parabola(directrix=d1) + pa3 = Parabola(p1, d1) + pa4 = Parabola(p2, d2) + pa5 = Parabola(p2, d4) + pa6 = Parabola(p3, d2) + pa7 = Parabola(p2, d1) + pa8 = Parabola(p4, d1) + pa9 = Parabola(p4, d3) + pa10 = Parabola(p5, d5) + pa11 = Parabola(p5, d6) + d = Line(Point(3, 7), Point(2, 9)) + pa12 = Parabola(Point(7, 8), d) + pa12r = Parabola(Point(7, 8).reflect(d), d) + + raises(ValueError, lambda: + Parabola(Point(7, 8, 9), Line(Point(6, 7), Point(7, 7)))) + raises(ValueError, lambda: + Parabola(Point(0, 2), Line(Point(7, 2), Point(6, 2)))) + raises(ValueError, lambda: Parabola(Point(7, 8), Point(3, 8))) + + # Basic Stuff + assert pa1.focus == Point(0, 0) + assert pa1.ambient_dimension == S(2) + assert pa2 == pa3 + assert pa4 != pa7 + assert pa6 != pa7 + assert pa6.focus == Point2D(0, 4) + assert pa6.focal_length == 1 + assert pa6.p_parameter == -1 + assert pa6.vertex == Point2D(0, 5) + assert pa6.eccentricity == 1 + assert pa7.focus == Point2D(3, 7) + assert pa7.focal_length == half + assert pa7.p_parameter == -half + assert pa7.vertex == Point2D(7*half, 7) + assert pa4.focal_length == half + assert pa4.p_parameter == half + assert pa4.vertex == Point2D(3, 13*half) + assert pa8.focal_length == 1 + assert pa8.p_parameter == 1 + assert pa8.vertex == Point2D(5, 0) + assert pa4.focal_length == pa5.focal_length + assert pa4.p_parameter == pa5.p_parameter + assert pa4.vertex == pa5.vertex + assert pa4.equation() == pa5.equation() + assert pa8.focal_length == pa9.focal_length + assert pa8.p_parameter == pa9.p_parameter + assert pa8.vertex == pa9.vertex + assert pa8.equation() == pa9.equation() + assert pa10.focal_length == pa11.focal_length == sqrt((a - b) ** 2) / 2 # if a, b real == abs(a - b)/2 + assert pa11.vertex == Point(*pa10.vertex[::-1]) == Point(a, + a - sqrt((a - b)**2)*sign(a - b)/2) # change axis x->y, y->x on pa10 + aos = pa12.axis_of_symmetry + assert aos == Line(Point(7, 8), Point(5, 7)) + assert pa12.directrix == Line(Point(3, 7), Point(2, 9)) + assert pa12.directrix.angle_between(aos) == S.Pi/2 + assert pa12.eccentricity == 1 + assert pa12.equation(x, y) == (x - 7)**2 + (y - 8)**2 - (-2*x - y + 13)**2/5 + assert pa12.focal_length == 9*sqrt(5)/10 + assert pa12.focus == Point(7, 8) + assert pa12.p_parameter == 9*sqrt(5)/10 + assert pa12.vertex == Point2D(S(26)/5, S(71)/10) + assert pa12r.focal_length == 9*sqrt(5)/10 + assert pa12r.focus == Point(-S(1)/5, S(22)/5) + assert pa12r.p_parameter == -9*sqrt(5)/10 + assert pa12r.vertex == Point(S(8)/5, S(53)/10) + + +def test_parabola_intersection(): + l1 = Line(Point(1, -2), Point(-1,-2)) + l2 = Line(Point(1, 2), Point(-1,2)) + l3 = Line(Point(1, 0), Point(-1,0)) + + p1 = Point(0,0) + p2 = Point(0, -2) + p3 = Point(120, -12) + parabola1 = Parabola(p1, l1) + + # parabola with parabola + assert parabola1.intersection(parabola1) == [parabola1] + assert parabola1.intersection(Parabola(p1, l2)) == [Point2D(-2, 0), Point2D(2, 0)] + assert parabola1.intersection(Parabola(p2, l3)) == [Point2D(0, -1)] + assert parabola1.intersection(Parabola(Point(16, 0), l1)) == [Point2D(8, 15)] + assert parabola1.intersection(Parabola(Point(0, 16), l1)) == [Point2D(-6, 8), Point2D(6, 8)] + assert parabola1.intersection(Parabola(p3, l3)) == [] + # parabola with point + assert parabola1.intersection(p1) == [] + assert parabola1.intersection(Point2D(0, -1)) == [Point2D(0, -1)] + assert parabola1.intersection(Point2D(4, 3)) == [Point2D(4, 3)] + # parabola with line + assert parabola1.intersection(Line(Point2D(-7, 3), Point(12, 3))) == [Point2D(-4, 3), Point2D(4, 3)] + assert parabola1.intersection(Line(Point(-4, -1), Point(4, -1))) == [Point(0, -1)] + assert parabola1.intersection(Line(Point(2, 0), Point(0, -2))) == [Point2D(2, 0)] + raises(TypeError, lambda: parabola1.intersection(Line(Point(0, 0, 0), Point(1, 1, 1)))) + # parabola with segment + assert parabola1.intersection(Segment2D((-4, -5), (4, 3))) == [Point2D(0, -1), Point2D(4, 3)] + assert parabola1.intersection(Segment2D((0, -5), (0, 6))) == [Point2D(0, -1)] + assert parabola1.intersection(Segment2D((-12, -65), (14, -68))) == [] + # parabola with ray + assert parabola1.intersection(Ray2D((-4, -5), (4, 3))) == [Point2D(0, -1), Point2D(4, 3)] + assert parabola1.intersection(Ray2D((0, 7), (1, 14))) == [Point2D(14 + 2*sqrt(57), 105 + 14*sqrt(57))] + assert parabola1.intersection(Ray2D((0, 7), (0, 14))) == [] + # parabola with ellipse/circle + assert parabola1.intersection(Circle(p1, 2)) == [Point2D(-2, 0), Point2D(2, 0)] + assert parabola1.intersection(Circle(p2, 1)) == [Point2D(0, -1)] + assert parabola1.intersection(Ellipse(p2, 2, 1)) == [Point2D(0, -1)] + assert parabola1.intersection(Ellipse(Point(0, 19), 5, 7)) == [] + assert parabola1.intersection(Ellipse((0, 3), 12, 4)) == [ + Point2D(0, -1), + Point2D(-4*sqrt(17)/3, Rational(59, 9)), + Point2D(4*sqrt(17)/3, Rational(59, 9))] + # parabola with unsupported type + raises(TypeError, lambda: parabola1.intersection(2)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_plane.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_plane.py new file mode 100644 index 0000000000000000000000000000000000000000..1010fce5c3bc68348eacee13f29c1d7588f17e39 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_plane.py @@ -0,0 +1,268 @@ +from sympy.core.numbers import (Rational, pi) +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, symbols) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (asin, cos, sin) +from sympy.geometry import Line, Point, Ray, Segment, Point3D, Line3D, Ray3D, Segment3D, Plane, Circle +from sympy.geometry.util import are_coplanar +from sympy.testing.pytest import raises + + +def test_plane(): + x, y, z, u, v = symbols('x y z u v', real=True) + p1 = Point3D(0, 0, 0) + p2 = Point3D(1, 1, 1) + p3 = Point3D(1, 2, 3) + pl3 = Plane(p1, p2, p3) + pl4 = Plane(p1, normal_vector=(1, 1, 1)) + pl4b = Plane(p1, p2) + pl5 = Plane(p3, normal_vector=(1, 2, 3)) + pl6 = Plane(Point3D(2, 3, 7), normal_vector=(2, 2, 2)) + pl7 = Plane(Point3D(1, -5, -6), normal_vector=(1, -2, 1)) + pl8 = Plane(p1, normal_vector=(0, 0, 1)) + pl9 = Plane(p1, normal_vector=(0, 12, 0)) + pl10 = Plane(p1, normal_vector=(-2, 0, 0)) + pl11 = Plane(p2, normal_vector=(0, 0, 1)) + l1 = Line3D(Point3D(5, 0, 0), Point3D(1, -1, 1)) + l2 = Line3D(Point3D(0, -2, 0), Point3D(3, 1, 1)) + l3 = Line3D(Point3D(0, -1, 0), Point3D(5, -1, 9)) + + raises(ValueError, lambda: Plane(p1, p1, p1)) + + assert Plane(p1, p2, p3) != Plane(p1, p3, p2) + assert Plane(p1, p2, p3).is_coplanar(Plane(p1, p3, p2)) + assert Plane(p1, p2, p3).is_coplanar(p1) + assert Plane(p1, p2, p3).is_coplanar(Circle(p1, 1)) is False + assert Plane(p1, normal_vector=(0, 0, 1)).is_coplanar(Circle(p1, 1)) + + assert pl3 == Plane(Point3D(0, 0, 0), normal_vector=(1, -2, 1)) + assert pl3 != pl4 + assert pl4 == pl4b + assert pl5 == Plane(Point3D(1, 2, 3), normal_vector=(1, 2, 3)) + + assert pl5.equation(x, y, z) == x + 2*y + 3*z - 14 + assert pl3.equation(x, y, z) == x - 2*y + z + + assert pl3.p1 == p1 + assert pl4.p1 == p1 + assert pl5.p1 == p3 + + assert pl4.normal_vector == (1, 1, 1) + assert pl5.normal_vector == (1, 2, 3) + + assert p1 in pl3 + assert p1 in pl4 + assert p3 in pl5 + + assert pl3.projection(Point(0, 0)) == p1 + p = pl3.projection(Point3D(1, 1, 0)) + assert p == Point3D(Rational(7, 6), Rational(2, 3), Rational(1, 6)) + assert p in pl3 + + l = pl3.projection_line(Line(Point(0, 0), Point(1, 1))) + assert l == Line3D(Point3D(0, 0, 0), Point3D(Rational(7, 6), Rational(2, 3), Rational(1, 6))) + assert l in pl3 + # get a segment that does not intersect the plane which is also + # parallel to pl3's normal veector + t = Dummy() + r = pl3.random_point() + a = pl3.perpendicular_line(r).arbitrary_point(t) + s = Segment3D(a.subs(t, 1), a.subs(t, 2)) + assert s.p1 not in pl3 and s.p2 not in pl3 + assert pl3.projection_line(s).equals(r) + assert pl3.projection_line(Segment(Point(1, 0), Point(1, 1))) == \ + Segment3D(Point3D(Rational(5, 6), Rational(1, 3), Rational(-1, 6)), Point3D(Rational(7, 6), Rational(2, 3), Rational(1, 6))) + assert pl6.projection_line(Ray(Point(1, 0), Point(1, 1))) == \ + Ray3D(Point3D(Rational(14, 3), Rational(11, 3), Rational(11, 3)), Point3D(Rational(13, 3), Rational(13, 3), Rational(10, 3))) + assert pl3.perpendicular_line(r.args) == pl3.perpendicular_line(r) + + assert pl3.is_parallel(pl6) is False + assert pl4.is_parallel(pl6) + assert pl3.is_parallel(Line(p1, p2)) + assert pl6.is_parallel(l1) is False + + assert pl3.is_perpendicular(pl6) + assert pl4.is_perpendicular(pl7) + assert pl6.is_perpendicular(pl7) + assert pl6.is_perpendicular(pl4) is False + assert pl6.is_perpendicular(l1) is False + assert pl6.is_perpendicular(Line((0, 0, 0), (1, 1, 1))) + assert pl6.is_perpendicular((1, 1)) is False + + assert pl6.distance(pl6.arbitrary_point(u, v)) == 0 + assert pl7.distance(pl7.arbitrary_point(u, v)) == 0 + assert pl6.distance(pl6.arbitrary_point(t)) == 0 + assert pl7.distance(pl7.arbitrary_point(t)) == 0 + assert pl6.p1.distance(pl6.arbitrary_point(t)).simplify() == 1 + assert pl7.p1.distance(pl7.arbitrary_point(t)).simplify() == 1 + assert pl3.arbitrary_point(t) == Point3D(-sqrt(30)*sin(t)/30 + \ + 2*sqrt(5)*cos(t)/5, sqrt(30)*sin(t)/15 + sqrt(5)*cos(t)/5, sqrt(30)*sin(t)/6) + assert pl3.arbitrary_point(u, v) == Point3D(2*u - v, u + 2*v, 5*v) + + assert pl7.distance(Point3D(1, 3, 5)) == 5*sqrt(6)/6 + assert pl6.distance(Point3D(0, 0, 0)) == 4*sqrt(3) + assert pl6.distance(pl6.p1) == 0 + assert pl7.distance(pl6) == 0 + assert pl7.distance(l1) == 0 + assert pl6.distance(Segment3D(Point3D(2, 3, 1), Point3D(1, 3, 4))) == \ + pl6.distance(Point3D(1, 3, 4)) == 4*sqrt(3)/3 + assert pl6.distance(Segment3D(Point3D(1, 3, 4), Point3D(0, 3, 7))) == \ + pl6.distance(Point3D(0, 3, 7)) == 2*sqrt(3)/3 + assert pl6.distance(Segment3D(Point3D(0, 3, 7), Point3D(-1, 3, 10))) == 0 + assert pl6.distance(Segment3D(Point3D(-1, 3, 10), Point3D(-2, 3, 13))) == 0 + assert pl6.distance(Segment3D(Point3D(-2, 3, 13), Point3D(-3, 3, 16))) == \ + pl6.distance(Point3D(-2, 3, 13)) == 2*sqrt(3)/3 + assert pl6.distance(Plane(Point3D(5, 5, 5), normal_vector=(8, 8, 8))) == sqrt(3) + assert pl6.distance(Ray3D(Point3D(1, 3, 4), direction_ratio=[1, 0, -3])) == 4*sqrt(3)/3 + assert pl6.distance(Ray3D(Point3D(2, 3, 1), direction_ratio=[-1, 0, 3])) == 0 + + + assert pl6.angle_between(pl3) == pi/2 + assert pl6.angle_between(pl6) == 0 + assert pl6.angle_between(pl4) == 0 + assert pl7.angle_between(Line3D(Point3D(2, 3, 5), Point3D(2, 4, 6))) == \ + -asin(sqrt(3)/6) + assert pl6.angle_between(Ray3D(Point3D(2, 4, 1), Point3D(6, 5, 3))) == \ + asin(sqrt(7)/3) + assert pl7.angle_between(Segment3D(Point3D(5, 6, 1), Point3D(1, 2, 4))) == \ + asin(7*sqrt(246)/246) + + assert are_coplanar(l1, l2, l3) is False + assert are_coplanar(l1) is False + assert are_coplanar(Point3D(2, 7, 2), Point3D(0, 0, 2), + Point3D(1, 1, 2), Point3D(1, 2, 2)) + assert are_coplanar(Plane(p1, p2, p3), Plane(p1, p3, p2)) + assert Plane.are_concurrent(pl3, pl4, pl5) is False + assert Plane.are_concurrent(pl6) is False + raises(ValueError, lambda: Plane.are_concurrent(Point3D(0, 0, 0))) + raises(ValueError, lambda: Plane((1, 2, 3), normal_vector=(0, 0, 0))) + + assert pl3.parallel_plane(Point3D(1, 2, 5)) == Plane(Point3D(1, 2, 5), \ + normal_vector=(1, -2, 1)) + + # perpendicular_plane + p = Plane((0, 0, 0), (1, 0, 0)) + # default + assert p.perpendicular_plane() == Plane(Point3D(0, 0, 0), (0, 1, 0)) + # 1 pt + assert p.perpendicular_plane(Point3D(1, 0, 1)) == \ + Plane(Point3D(1, 0, 1), (0, 1, 0)) + # pts as tuples + assert p.perpendicular_plane((1, 0, 1), (1, 1, 1)) == \ + Plane(Point3D(1, 0, 1), (0, 0, -1)) + # more than two planes + raises(ValueError, lambda: p.perpendicular_plane((1, 0, 1), (1, 1, 1), (1, 1, 0))) + + a, b = Point3D(0, 0, 0), Point3D(0, 1, 0) + Z = (0, 0, 1) + p = Plane(a, normal_vector=Z) + # case 4 + assert p.perpendicular_plane(a, b) == Plane(a, (1, 0, 0)) + n = Point3D(*Z) + # case 1 + assert p.perpendicular_plane(a, n) == Plane(a, (-1, 0, 0)) + # case 2 + assert Plane(a, normal_vector=b.args).perpendicular_plane(a, a + b) == \ + Plane(Point3D(0, 0, 0), (1, 0, 0)) + # case 1&3 + assert Plane(b, normal_vector=Z).perpendicular_plane(b, b + n) == \ + Plane(Point3D(0, 1, 0), (-1, 0, 0)) + # case 2&3 + assert Plane(b, normal_vector=b.args).perpendicular_plane(n, n + b) == \ + Plane(Point3D(0, 0, 1), (1, 0, 0)) + + p = Plane(a, normal_vector=(0, 0, 1)) + assert p.perpendicular_plane() == Plane(a, normal_vector=(1, 0, 0)) + + assert pl6.intersection(pl6) == [pl6] + assert pl4.intersection(pl4.p1) == [pl4.p1] + assert pl3.intersection(pl6) == [ + Line3D(Point3D(8, 4, 0), Point3D(2, 4, 6))] + assert pl3.intersection(Line3D(Point3D(1,2,4), Point3D(4,4,2))) == [ + Point3D(2, Rational(8, 3), Rational(10, 3))] + assert pl3.intersection(Plane(Point3D(6, 0, 0), normal_vector=(2, -5, 3)) + ) == [Line3D(Point3D(-24, -12, 0), Point3D(-25, -13, -1))] + assert pl6.intersection(Ray3D(Point3D(2, 3, 1), Point3D(1, 3, 4))) == [ + Point3D(-1, 3, 10)] + assert pl6.intersection(Segment3D(Point3D(2, 3, 1), Point3D(1, 3, 4))) == [] + assert pl7.intersection(Line(Point(2, 3), Point(4, 2))) == [ + Point3D(Rational(13, 2), Rational(3, 4), 0)] + r = Ray(Point(2, 3), Point(4, 2)) + assert Plane((1,2,0), normal_vector=(0,0,1)).intersection(r) == [ + Ray3D(Point(2, 3), Point(4, 2))] + assert pl9.intersection(pl8) == [Line3D(Point3D(0, 0, 0), Point3D(12, 0, 0))] + assert pl10.intersection(pl11) == [Line3D(Point3D(0, 0, 1), Point3D(0, 2, 1))] + assert pl4.intersection(pl8) == [Line3D(Point3D(0, 0, 0), Point3D(1, -1, 0))] + assert pl11.intersection(pl8) == [] + assert pl9.intersection(pl11) == [Line3D(Point3D(0, 0, 1), Point3D(12, 0, 1))] + assert pl9.intersection(pl4) == [Line3D(Point3D(0, 0, 0), Point3D(12, 0, -12))] + assert pl3.random_point() in pl3 + assert pl3.random_point(seed=1) in pl3 + + # test geometrical entity using equals + assert pl4.intersection(pl4.p1)[0].equals(pl4.p1) + assert pl3.intersection(pl6)[0].equals(Line3D(Point3D(8, 4, 0), Point3D(2, 4, 6))) + pl8 = Plane((1, 2, 0), normal_vector=(0, 0, 1)) + assert pl8.intersection(Line3D(p1, (1, 12, 0)))[0].equals(Line((0, 0, 0), (0.1, 1.2, 0))) + assert pl8.intersection(Ray3D(p1, (1, 12, 0)))[0].equals(Ray((0, 0, 0), (1, 12, 0))) + assert pl8.intersection(Segment3D(p1, (21, 1, 0)))[0].equals(Segment3D(p1, (21, 1, 0))) + assert pl8.intersection(Plane(p1, normal_vector=(0, 0, 112)))[0].equals(pl8) + assert pl8.intersection(Plane(p1, normal_vector=(0, 12, 0)))[0].equals( + Line3D(p1, direction_ratio=(112 * pi, 0, 0))) + assert pl8.intersection(Plane(p1, normal_vector=(11, 0, 1)))[0].equals( + Line3D(p1, direction_ratio=(0, -11, 0))) + assert pl8.intersection(Plane(p1, normal_vector=(1, 0, 11)))[0].equals( + Line3D(p1, direction_ratio=(0, 11, 0))) + assert pl8.intersection(Plane(p1, normal_vector=(-1, -1, -11)))[0].equals( + Line3D(p1, direction_ratio=(1, -1, 0))) + assert pl3.random_point() in pl3 + assert len(pl8.intersection(Ray3D(Point3D(0, 2, 3), Point3D(1, 0, 3)))) == 0 + # check if two plane are equals + assert pl6.intersection(pl6)[0].equals(pl6) + assert pl8.equals(Plane(p1, normal_vector=(0, 12, 0))) is False + assert pl8.equals(pl8) + assert pl8.equals(Plane(p1, normal_vector=(0, 0, -12))) + assert pl8.equals(Plane(p1, normal_vector=(0, 0, -12*sqrt(3)))) + assert pl8.equals(p1) is False + + # issue 8570 + l2 = Line3D(Point3D(Rational(50000004459633, 5000000000000), + Rational(-891926590718643, 1000000000000000), + Rational(231800966893633, 100000000000000)), + Point3D(Rational(50000004459633, 50000000000000), + Rational(-222981647679771, 250000000000000), + Rational(231800966893633, 100000000000000))) + + p2 = Plane(Point3D(Rational(402775636372767, 100000000000000), + Rational(-97224357654973, 100000000000000), + Rational(216793600814789, 100000000000000)), + (-S('9.00000087501922'), -S('4.81170658872543e-13'), + S('0.0'))) + + assert str([i.n(2) for i in p2.intersection(l2)]) == \ + '[Point3D(4.0, -0.89, 2.3)]' + + +def test_dimension_normalization(): + A = Plane(Point3D(1, 1, 2), normal_vector=(1, 1, 1)) + b = Point(1, 1) + assert A.projection(b) == Point(Rational(5, 3), Rational(5, 3), Rational(2, 3)) + + a, b = Point(0, 0), Point3D(0, 1) + Z = (0, 0, 1) + p = Plane(a, normal_vector=Z) + assert p.perpendicular_plane(a, b) == Plane(Point3D(0, 0, 0), (1, 0, 0)) + assert Plane((1, 2, 1), (2, 1, 0), (3, 1, 2) + ).intersection((2, 1)) == [Point(2, 1, 0)] + + +def test_parameter_value(): + t, u, v = symbols("t, u v") + p1, p2, p3 = Point(0, 0, 0), Point(0, 0, 1), Point(0, 1, 0) + p = Plane(p1, p2, p3) + assert p.parameter_value((0, -3, 2), t) == {t: asin(2*sqrt(13)/13)} + assert p.parameter_value((0, -3, 2), u, v) == {u: 3, v: 2} + assert p.parameter_value(p1, t) == p1 + raises(ValueError, lambda: p.parameter_value((1, 0, 0), t)) + raises(ValueError, lambda: p.parameter_value(Line(Point(0, 0), Point(1, 1)), t)) + raises(ValueError, lambda: p.parameter_value((0, -3, 2), t, 1)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_point.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_point.py new file mode 100644 index 0000000000000000000000000000000000000000..1f2b2768eb3fba2009f702351de1aac3ed6e71d4 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_point.py @@ -0,0 +1,481 @@ +from sympy.core.basic import Basic +from sympy.core.numbers import (I, Rational, pi) +from sympy.core.parameters import evaluate +from sympy.core.singleton import S +from sympy.core.symbol import Symbol +from sympy.core.sympify import sympify +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.geometry import Line, Point, Point2D, Point3D, Line3D, Plane +from sympy.geometry.entity import rotate, scale, translate, GeometryEntity +from sympy.matrices import Matrix +from sympy.utilities.iterables import subsets, permutations, cartes +from sympy.utilities.misc import Undecidable +from sympy.testing.pytest import raises, warns + + +def test_point(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + x1 = Symbol('x1', real=True) + x2 = Symbol('x2', real=True) + y1 = Symbol('y1', real=True) + y2 = Symbol('y2', real=True) + half = S.Half + p1 = Point(x1, x2) + p2 = Point(y1, y2) + p3 = Point(0, 0) + p4 = Point(1, 1) + p5 = Point(0, 1) + line = Line(Point(1, 0), slope=1) + + assert p1 in p1 + assert p1 not in p2 + assert p2.y == y2 + assert (p3 + p4) == p4 + assert (p2 - p1) == Point(y1 - x1, y2 - x2) + assert -p2 == Point(-y1, -y2) + raises(TypeError, lambda: Point(1)) + raises(ValueError, lambda: Point([1])) + raises(ValueError, lambda: Point(3, I)) + raises(ValueError, lambda: Point(2*I, I)) + raises(ValueError, lambda: Point(3 + I, I)) + + assert Point(34.05, sqrt(3)) == Point(Rational(681, 20), sqrt(3)) + assert Point.midpoint(p3, p4) == Point(half, half) + assert Point.midpoint(p1, p4) == Point(half + half*x1, half + half*x2) + assert Point.midpoint(p2, p2) == p2 + assert p2.midpoint(p2) == p2 + assert p1.origin == Point(0, 0) + + assert Point.distance(p3, p4) == sqrt(2) + assert Point.distance(p1, p1) == 0 + assert Point.distance(p3, p2) == sqrt(p2.x**2 + p2.y**2) + raises(TypeError, lambda: Point.distance(p1, 0)) + raises(TypeError, lambda: Point.distance(p1, GeometryEntity())) + + # distance should be symmetric + assert p1.distance(line) == line.distance(p1) + assert p4.distance(line) == line.distance(p4) + + assert Point.taxicab_distance(p4, p3) == 2 + + assert Point.canberra_distance(p4, p5) == 1 + raises(ValueError, lambda: Point.canberra_distance(p3, p3)) + + p1_1 = Point(x1, x1) + p1_2 = Point(y2, y2) + p1_3 = Point(x1 + 1, x1) + assert Point.is_collinear(p3) + + with warns(UserWarning, test_stacklevel=False): + assert Point.is_collinear(p3, Point(p3, dim=4)) + assert p3.is_collinear() + assert Point.is_collinear(p3, p4) + assert Point.is_collinear(p3, p4, p1_1, p1_2) + assert Point.is_collinear(p3, p4, p1_1, p1_3) is False + assert Point.is_collinear(p3, p3, p4, p5) is False + + raises(TypeError, lambda: Point.is_collinear(line)) + raises(TypeError, lambda: p1_1.is_collinear(line)) + + assert p3.intersection(Point(0, 0)) == [p3] + assert p3.intersection(p4) == [] + assert p3.intersection(line) == [] + with warns(UserWarning, test_stacklevel=False): + assert Point.intersection(Point(0, 0, 0), Point(0, 0)) == [Point(0, 0, 0)] + + x_pos = Symbol('x', positive=True) + p2_1 = Point(x_pos, 0) + p2_2 = Point(0, x_pos) + p2_3 = Point(-x_pos, 0) + p2_4 = Point(0, -x_pos) + p2_5 = Point(x_pos, 5) + assert Point.is_concyclic(p2_1) + assert Point.is_concyclic(p2_1, p2_2) + assert Point.is_concyclic(p2_1, p2_2, p2_3, p2_4) + for pts in permutations((p2_1, p2_2, p2_3, p2_5)): + assert Point.is_concyclic(*pts) is False + assert Point.is_concyclic(p4, p4 * 2, p4 * 3) is False + assert Point(0, 0).is_concyclic((1, 1), (2, 2), (2, 1)) is False + assert Point.is_concyclic(Point(0, 0, 0, 0), Point(1, 0, 0, 0), Point(1, 1, 0, 0), Point(1, 1, 1, 0)) is False + + assert p1.is_scalar_multiple(p1) + assert p1.is_scalar_multiple(2*p1) + assert not p1.is_scalar_multiple(p2) + assert Point.is_scalar_multiple(Point(1, 1), (-1, -1)) + assert Point.is_scalar_multiple(Point(0, 0), (0, -1)) + # test when is_scalar_multiple can't be determined + raises(Undecidable, lambda: Point.is_scalar_multiple(Point(sympify("x1%y1"), sympify("x2%y2")), Point(0, 1))) + + assert Point(0, 1).orthogonal_direction == Point(1, 0) + assert Point(1, 0).orthogonal_direction == Point(0, 1) + + assert p1.is_zero is None + assert p3.is_zero + assert p4.is_zero is False + assert p1.is_nonzero is None + assert p3.is_nonzero is False + assert p4.is_nonzero + + assert p4.scale(2, 3) == Point(2, 3) + assert p3.scale(2, 3) == p3 + + assert p4.rotate(pi, Point(0.5, 0.5)) == p3 + assert p1.__radd__(p2) == p1.midpoint(p2).scale(2, 2) + assert (-p3).__rsub__(p4) == p3.midpoint(p4).scale(2, 2) + + assert p4 * 5 == Point(5, 5) + assert p4 / 5 == Point(0.2, 0.2) + assert 5 * p4 == Point(5, 5) + + raises(ValueError, lambda: Point(0, 0) + 10) + + # Point differences should be simplified + assert Point(x*(x - 1), y) - Point(x**2 - x, y + 1) == Point(0, -1) + + a, b = S.Half, Rational(1, 3) + assert Point(a, b).evalf(2) == \ + Point(a.n(2), b.n(2), evaluate=False) + raises(ValueError, lambda: Point(1, 2) + 1) + + # test project + assert Point.project((0, 1), (1, 0)) == Point(0, 0) + assert Point.project((1, 1), (1, 0)) == Point(1, 0) + raises(ValueError, lambda: Point.project(p1, Point(0, 0))) + + # test transformations + p = Point(1, 0) + assert p.rotate(pi/2) == Point(0, 1) + assert p.rotate(pi/2, p) == p + p = Point(1, 1) + assert p.scale(2, 3) == Point(2, 3) + assert p.translate(1, 2) == Point(2, 3) + assert p.translate(1) == Point(2, 1) + assert p.translate(y=1) == Point(1, 2) + assert p.translate(*p.args) == Point(2, 2) + + # Check invalid input for transform + raises(ValueError, lambda: p3.transform(p3)) + raises(ValueError, lambda: p.transform(Matrix([[1, 0], [0, 1]]))) + + # test __contains__ + assert 0 in Point(0, 0, 0, 0) + assert 1 not in Point(0, 0, 0, 0) + + # test affine_rank + assert Point.affine_rank() == -1 + + +def test_point3D(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + x1 = Symbol('x1', real=True) + x2 = Symbol('x2', real=True) + x3 = Symbol('x3', real=True) + y1 = Symbol('y1', real=True) + y2 = Symbol('y2', real=True) + y3 = Symbol('y3', real=True) + half = S.Half + p1 = Point3D(x1, x2, x3) + p2 = Point3D(y1, y2, y3) + p3 = Point3D(0, 0, 0) + p4 = Point3D(1, 1, 1) + p5 = Point3D(0, 1, 2) + + assert p1 in p1 + assert p1 not in p2 + assert p2.y == y2 + assert (p3 + p4) == p4 + assert (p2 - p1) == Point3D(y1 - x1, y2 - x2, y3 - x3) + assert -p2 == Point3D(-y1, -y2, -y3) + + assert Point(34.05, sqrt(3)) == Point(Rational(681, 20), sqrt(3)) + assert Point3D.midpoint(p3, p4) == Point3D(half, half, half) + assert Point3D.midpoint(p1, p4) == Point3D(half + half*x1, half + half*x2, + half + half*x3) + assert Point3D.midpoint(p2, p2) == p2 + assert p2.midpoint(p2) == p2 + + assert Point3D.distance(p3, p4) == sqrt(3) + assert Point3D.distance(p1, p1) == 0 + assert Point3D.distance(p3, p2) == sqrt(p2.x**2 + p2.y**2 + p2.z**2) + + p1_1 = Point3D(x1, x1, x1) + p1_2 = Point3D(y2, y2, y2) + p1_3 = Point3D(x1 + 1, x1, x1) + Point3D.are_collinear(p3) + assert Point3D.are_collinear(p3, p4) + assert Point3D.are_collinear(p3, p4, p1_1, p1_2) + assert Point3D.are_collinear(p3, p4, p1_1, p1_3) is False + assert Point3D.are_collinear(p3, p3, p4, p5) is False + + assert p3.intersection(Point3D(0, 0, 0)) == [p3] + assert p3.intersection(p4) == [] + + + assert p4 * 5 == Point3D(5, 5, 5) + assert p4 / 5 == Point3D(0.2, 0.2, 0.2) + assert 5 * p4 == Point3D(5, 5, 5) + + raises(ValueError, lambda: Point3D(0, 0, 0) + 10) + + # Test coordinate properties + assert p1.coordinates == (x1, x2, x3) + assert p2.coordinates == (y1, y2, y3) + assert p3.coordinates == (0, 0, 0) + assert p4.coordinates == (1, 1, 1) + assert p5.coordinates == (0, 1, 2) + assert p5.x == 0 + assert p5.y == 1 + assert p5.z == 2 + + # Point differences should be simplified + assert Point3D(x*(x - 1), y, 2) - Point3D(x**2 - x, y + 1, 1) == \ + Point3D(0, -1, 1) + + a, b, c = S.Half, Rational(1, 3), Rational(1, 4) + assert Point3D(a, b, c).evalf(2) == \ + Point(a.n(2), b.n(2), c.n(2), evaluate=False) + raises(ValueError, lambda: Point3D(1, 2, 3) + 1) + + # test transformations + p = Point3D(1, 1, 1) + assert p.scale(2, 3) == Point3D(2, 3, 1) + assert p.translate(1, 2) == Point3D(2, 3, 1) + assert p.translate(1) == Point3D(2, 1, 1) + assert p.translate(z=1) == Point3D(1, 1, 2) + assert p.translate(*p.args) == Point3D(2, 2, 2) + + # Test __new__ + assert Point3D(0.1, 0.2, evaluate=False, on_morph='ignore').args[0].is_Float + + # Test length property returns correctly + assert p.length == 0 + assert p1_1.length == 0 + assert p1_2.length == 0 + + # Test are_colinear type error + raises(TypeError, lambda: Point3D.are_collinear(p, x)) + + # Test are_coplanar + assert Point.are_coplanar() + assert Point.are_coplanar((1, 2, 0), (1, 2, 0), (1, 3, 0)) + assert Point.are_coplanar((1, 2, 0), (1, 2, 3)) + with warns(UserWarning, test_stacklevel=False): + raises(ValueError, lambda: Point2D.are_coplanar((1, 2), (1, 2, 3))) + assert Point3D.are_coplanar((1, 2, 0), (1, 2, 3)) + assert Point.are_coplanar((0, 0, 0), (1, 1, 0), (1, 1, 1), (1, 2, 1)) is False + planar2 = Point3D(1, -1, 1) + planar3 = Point3D(-1, 1, 1) + assert Point3D.are_coplanar(p, planar2, planar3) == True + assert Point3D.are_coplanar(p, planar2, planar3, p3) == False + assert Point.are_coplanar(p, planar2) + planar2 = Point3D(1, 1, 2) + planar3 = Point3D(1, 1, 3) + assert Point3D.are_coplanar(p, planar2, planar3) # line, not plane + plane = Plane((1, 2, 1), (2, 1, 0), (3, 1, 2)) + assert Point.are_coplanar(*[plane.projection(((-1)**i, i)) for i in range(4)]) + + # all 2D points are coplanar + assert Point.are_coplanar(Point(x, y), Point(x, x + y), Point(y, x + 2)) is True + + # Test Intersection + assert planar2.intersection(Line3D(p, planar3)) == [Point3D(1, 1, 2)] + + # Test Scale + assert planar2.scale(1, 1, 1) == planar2 + assert planar2.scale(2, 2, 2, planar3) == Point3D(1, 1, 1) + assert planar2.scale(1, 1, 1, p3) == planar2 + + # Test Transform + identity = Matrix([[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1]]) + assert p.transform(identity) == p + trans = Matrix([[1, 0, 0, 1], [0, 1, 0, 1], [0, 0, 1, 1], [0, 0, 0, 1]]) + assert p.transform(trans) == Point3D(2, 2, 2) + raises(ValueError, lambda: p.transform(p)) + raises(ValueError, lambda: p.transform(Matrix([[1, 0], [0, 1]]))) + + # Test Equals + assert p.equals(x1) == False + + # Test __sub__ + p_4d = Point(0, 0, 0, 1) + with warns(UserWarning, test_stacklevel=False): + assert p - p_4d == Point(1, 1, 1, -1) + p_4d3d = Point(0, 0, 1, 0) + with warns(UserWarning, test_stacklevel=False): + assert p - p_4d3d == Point(1, 1, 0, 0) + + +def test_Point2D(): + + # Test Distance + p1 = Point2D(1, 5) + p2 = Point2D(4, 2.5) + p3 = (6, 3) + assert p1.distance(p2) == sqrt(61)/2 + assert p2.distance(p3) == sqrt(17)/2 + + # Test coordinates + assert p1.x == 1 + assert p1.y == 5 + assert p2.x == 4 + assert p2.y == S(5)/2 + assert p1.coordinates == (1, 5) + assert p2.coordinates == (4, S(5)/2) + + # test bounds + assert p1.bounds == (1, 5, 1, 5) + +def test_issue_9214(): + p1 = Point3D(4, -2, 6) + p2 = Point3D(1, 2, 3) + p3 = Point3D(7, 2, 3) + + assert Point3D.are_collinear(p1, p2, p3) is False + + +def test_issue_11617(): + p1 = Point3D(1,0,2) + p2 = Point2D(2,0) + + with warns(UserWarning, test_stacklevel=False): + assert p1.distance(p2) == sqrt(5) + + +def test_transform(): + p = Point(1, 1) + assert p.transform(rotate(pi/2)) == Point(-1, 1) + assert p.transform(scale(3, 2)) == Point(3, 2) + assert p.transform(translate(1, 2)) == Point(2, 3) + assert Point(1, 1).scale(2, 3, (4, 5)) == \ + Point(-2, -7) + assert Point(1, 1).translate(4, 5) == \ + Point(5, 6) + + +def test_concyclic_doctest_bug(): + p1, p2 = Point(-1, 0), Point(1, 0) + p3, p4 = Point(0, 1), Point(-1, 2) + assert Point.is_concyclic(p1, p2, p3) + assert not Point.is_concyclic(p1, p2, p3, p4) + + +def test_arguments(): + """Functions accepting `Point` objects in `geometry` + should also accept tuples and lists and + automatically convert them to points.""" + + singles2d = ((1,2), [1,2], Point(1,2)) + singles2d2 = ((1,3), [1,3], Point(1,3)) + doubles2d = cartes(singles2d, singles2d2) + p2d = Point2D(1,2) + singles3d = ((1,2,3), [1,2,3], Point(1,2,3)) + doubles3d = subsets(singles3d, 2) + p3d = Point3D(1,2,3) + singles4d = ((1,2,3,4), [1,2,3,4], Point(1,2,3,4)) + doubles4d = subsets(singles4d, 2) + p4d = Point(1,2,3,4) + + # test 2D + test_single = ['distance', 'is_scalar_multiple', 'taxicab_distance', 'midpoint', 'intersection', 'dot', 'equals', '__add__', '__sub__'] + test_double = ['is_concyclic', 'is_collinear'] + for p in singles2d: + Point2D(p) + for func in test_single: + for p in singles2d: + getattr(p2d, func)(p) + for func in test_double: + for p in doubles2d: + getattr(p2d, func)(*p) + + # test 3D + test_double = ['is_collinear'] + for p in singles3d: + Point3D(p) + for func in test_single: + for p in singles3d: + getattr(p3d, func)(p) + for func in test_double: + for p in doubles3d: + getattr(p3d, func)(*p) + + # test 4D + test_double = ['is_collinear'] + for p in singles4d: + Point(p) + for func in test_single: + for p in singles4d: + getattr(p4d, func)(p) + for func in test_double: + for p in doubles4d: + getattr(p4d, func)(*p) + + # test evaluate=False for ops + x = Symbol('x') + a = Point(0, 1) + assert a + (0.1, x) == Point(0.1, 1 + x, evaluate=False) + a = Point(0, 1) + assert a/10.0 == Point(0, 0.1, evaluate=False) + a = Point(0, 1) + assert a*10.0 == Point(0, 10.0, evaluate=False) + + # test evaluate=False when changing dimensions + u = Point(.1, .2, evaluate=False) + u4 = Point(u, dim=4, on_morph='ignore') + assert u4.args == (.1, .2, 0, 0) + assert all(i.is_Float for i in u4.args[:2]) + # and even when *not* changing dimensions + assert all(i.is_Float for i in Point(u).args) + + # never raise error if creating an origin + assert Point(dim=3, on_morph='error') + + # raise error with unmatched dimension + raises(ValueError, lambda: Point(1, 1, dim=3, on_morph='error')) + # test unknown on_morph + raises(ValueError, lambda: Point(1, 1, dim=3, on_morph='unknown')) + # test invalid expressions + raises(TypeError, lambda: Point(Basic(), Basic())) + +def test_unit(): + assert Point(1, 1).unit == Point(sqrt(2)/2, sqrt(2)/2) + + +def test_dot(): + raises(TypeError, lambda: Point(1, 2).dot(Line((0, 0), (1, 1)))) + + +def test__normalize_dimension(): + assert Point._normalize_dimension(Point(1, 2), Point(3, 4)) == [ + Point(1, 2), Point(3, 4)] + assert Point._normalize_dimension( + Point(1, 2), Point(3, 4, 0), on_morph='ignore') == [ + Point(1, 2, 0), Point(3, 4, 0)] + + +def test_issue_22684(): + # Used to give an error + with evaluate(False): + Point(1, 2) + + +def test_direction_cosine(): + p1 = Point3D(0, 0, 0) + p2 = Point3D(1, 1, 1) + + assert p1.direction_cosine(Point3D(1, 0, 0)) == [1, 0, 0] + assert p1.direction_cosine(Point3D(0, 1, 0)) == [0, 1, 0] + assert p1.direction_cosine(Point3D(0, 0, pi)) == [0, 0, 1] + + assert p1.direction_cosine(Point3D(5, 0, 0)) == [1, 0, 0] + assert p1.direction_cosine(Point3D(0, sqrt(3), 0)) == [0, 1, 0] + assert p1.direction_cosine(Point3D(0, 0, 5)) == [0, 0, 1] + + assert p1.direction_cosine(Point3D(2.4, 2.4, 0)) == [sqrt(2)/2, sqrt(2)/2, 0] + assert p1.direction_cosine(Point3D(1, 1, 1)) == [sqrt(3) / 3, sqrt(3) / 3, sqrt(3) / 3] + assert p1.direction_cosine(Point3D(-12, 0 -15)) == [-4*sqrt(41)/41, -5*sqrt(41)/41, 0] + + assert p2.direction_cosine(Point3D(0, 0, 0)) == [-sqrt(3) / 3, -sqrt(3) / 3, -sqrt(3) / 3] + assert p2.direction_cosine(Point3D(1, 1, 12)) == [0, 0, 1] + assert p2.direction_cosine(Point3D(12, 1, 12)) == [sqrt(2) / 2, 0, sqrt(2) / 2] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_polygon.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_polygon.py new file mode 100644 index 0000000000000000000000000000000000000000..520023349f363bdb12146465305c2a5650c80934 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_polygon.py @@ -0,0 +1,676 @@ +from sympy.core.numbers import (Float, Rational, oo, pi) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.complexes import Abs +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (acos, cos, sin) +from sympy.functions.elementary.trigonometric import tan +from sympy.geometry import (Circle, Ellipse, GeometryError, Point, Point2D, + Polygon, Ray, RegularPolygon, Segment, Triangle, + are_similar, convex_hull, intersection, Line, Ray2D) +from sympy.testing.pytest import raises, slow, warns +from sympy.core.random import verify_numerically +from sympy.geometry.polygon import rad, deg +from sympy.integrals.integrals import integrate +from sympy.utilities.iterables import rotate_left + + +def feq(a, b): + """Test if two floating point values are 'equal'.""" + t_float = Float("1.0E-10") + return -t_float < a - b < t_float + +@slow +def test_polygon(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + q = Symbol('q', real=True) + u = Symbol('u', real=True) + v = Symbol('v', real=True) + w = Symbol('w', real=True) + x1 = Symbol('x1', real=True) + half = S.Half + a, b, c = Point(0, 0), Point(2, 0), Point(3, 3) + t = Triangle(a, b, c) + assert Polygon(Point(0, 0)) == Point(0, 0) + assert Polygon(a, Point(1, 0), b, c) == t + assert Polygon(Point(1, 0), b, c, a) == t + assert Polygon(b, c, a, Point(1, 0)) == t + # 2 "remove folded" tests + assert Polygon(a, Point(3, 0), b, c) == t + assert Polygon(a, b, Point(3, -1), b, c) == t + # remove multiple collinear points + assert Polygon(Point(-4, 15), Point(-11, 15), Point(-15, 15), + Point(-15, 33/5), Point(-15, -87/10), Point(-15, -15), + Point(-42/5, -15), Point(-2, -15), Point(7, -15), Point(15, -15), + Point(15, -3), Point(15, 10), Point(15, 15)) == \ + Polygon(Point(-15, -15), Point(15, -15), Point(15, 15), Point(-15, 15)) + + p1 = Polygon( + Point(0, 0), Point(3, -1), + Point(6, 0), Point(4, 5), + Point(2, 3), Point(0, 3)) + p2 = Polygon( + Point(6, 0), Point(3, -1), + Point(0, 0), Point(0, 3), + Point(2, 3), Point(4, 5)) + p3 = Polygon( + Point(0, 0), Point(3, 0), + Point(5, 2), Point(4, 4)) + p4 = Polygon( + Point(0, 0), Point(4, 4), + Point(5, 2), Point(3, 0)) + p5 = Polygon( + Point(0, 0), Point(4, 4), + Point(0, 4)) + p6 = Polygon( + Point(-11, 1), Point(-9, 6.6), + Point(-4, -3), Point(-8.4, -8.7)) + p7 = Polygon( + Point(x, y), Point(q, u), + Point(v, w)) + p8 = Polygon( + Point(x, y), Point(v, w), + Point(q, u)) + p9 = Polygon( + Point(0, 0), Point(4, 4), + Point(3, 0), Point(5, 2)) + p10 = Polygon( + Point(0, 2), Point(2, 2), + Point(0, 0), Point(2, 0)) + p11 = Polygon(Point(0, 0), 1, n=3) + p12 = Polygon(Point(0, 0), 1, 0, n=3) + p13 = Polygon( + Point(0, 0),Point(8, 8), + Point(23, 20),Point(0, 20)) + p14 = Polygon(*rotate_left(p13.args, 1)) + + + r = Ray(Point(-9, 6.6), Point(-9, 5.5)) + # + # General polygon + # + assert p1 == p2 + assert len(p1.args) == 6 + assert len(p1.sides) == 6 + assert p1.perimeter == 5 + 2*sqrt(10) + sqrt(29) + sqrt(8) + assert p1.area == 22 + assert not p1.is_convex() + assert Polygon((-1, 1), (2, -1), (2, 1), (-1, -1), (3, 0) + ).is_convex() is False + # ensure convex for both CW and CCW point specification + assert p3.is_convex() + assert p4.is_convex() + dict5 = p5.angles + assert dict5[Point(0, 0)] == pi / 4 + assert dict5[Point(0, 4)] == pi / 2 + assert p5.encloses_point(Point(x, y)) is None + assert p5.encloses_point(Point(1, 3)) + assert p5.encloses_point(Point(0, 0)) is False + assert p5.encloses_point(Point(4, 0)) is False + assert p1.encloses(Circle(Point(2.5, 2.5), 5)) is False + assert p1.encloses(Ellipse(Point(2.5, 2), 5, 6)) is False + assert p5.plot_interval('x') == [x, 0, 1] + assert p5.distance( + Polygon(Point(10, 10), Point(14, 14), Point(10, 14))) == 6 * sqrt(2) + assert p5.distance( + Polygon(Point(1, 8), Point(5, 8), Point(8, 12), Point(1, 12))) == 4 + with warns(UserWarning, \ + match="Polygons may intersect producing erroneous output"): + Polygon(Point(0, 0), Point(1, 0), Point(1, 1)).distance( + Polygon(Point(0, 0), Point(0, 1), Point(1, 1))) + assert hash(p5) == hash(Polygon(Point(0, 0), Point(4, 4), Point(0, 4))) + assert hash(p1) == hash(p2) + assert hash(p7) == hash(p8) + assert hash(p3) != hash(p9) + assert p5 == Polygon(Point(4, 4), Point(0, 4), Point(0, 0)) + assert Polygon(Point(4, 4), Point(0, 4), Point(0, 0)) in p5 + assert p5 != Point(0, 4) + assert Point(0, 1) in p5 + assert p5.arbitrary_point('t').subs(Symbol('t', real=True), 0) == \ + Point(0, 0) + raises(ValueError, lambda: Polygon( + Point(x, 0), Point(0, y), Point(x, y)).arbitrary_point('x')) + assert p6.intersection(r) == [Point(-9, Rational(-84, 13)), Point(-9, Rational(33, 5))] + assert p10.area == 0 + assert p11 == RegularPolygon(Point(0, 0), 1, 3, 0) + assert p11 == p12 + assert p11.vertices[0] == Point(1, 0) + assert p11.args[0] == Point(0, 0) + p11.spin(pi/2) + assert p11.vertices[0] == Point(0, 1) + # + # Regular polygon + # + p1 = RegularPolygon(Point(0, 0), 10, 5) + p2 = RegularPolygon(Point(0, 0), 5, 5) + raises(GeometryError, lambda: RegularPolygon(Point(0, 0), Point(0, + 1), Point(1, 1))) + raises(GeometryError, lambda: RegularPolygon(Point(0, 0), 1, 2)) + raises(ValueError, lambda: RegularPolygon(Point(0, 0), 1, 2.5)) + + assert p1 != p2 + assert p1.interior_angle == pi*Rational(3, 5) + assert p1.exterior_angle == pi*Rational(2, 5) + assert p2.apothem == 5*cos(pi/5) + assert p2.circumcenter == p1.circumcenter == Point(0, 0) + assert p1.circumradius == p1.radius == 10 + assert p2.circumcircle == Circle(Point(0, 0), 5) + assert p2.incircle == Circle(Point(0, 0), p2.apothem) + assert p2.inradius == p2.apothem == (5 * (1 + sqrt(5)) / 4) + p2.spin(pi / 10) + dict1 = p2.angles + assert dict1[Point(0, 5)] == 3 * pi / 5 + assert p1.is_convex() + assert p1.rotation == 0 + assert p1.encloses_point(Point(0, 0)) + assert p1.encloses_point(Point(11, 0)) is False + assert p2.encloses_point(Point(0, 4.9)) + p1.spin(pi/3) + assert p1.rotation == pi/3 + assert p1.vertices[0] == Point(5, 5*sqrt(3)) + for var in p1.args: + if isinstance(var, Point): + assert var == Point(0, 0) + else: + assert var in (5, 10, pi / 3) + assert p1 != Point(0, 0) + assert p1 != p5 + + # while spin works in place (notice that rotation is 2pi/3 below) + # rotate returns a new object + p1_old = p1 + assert p1.rotate(pi/3) == RegularPolygon(Point(0, 0), 10, 5, pi*Rational(2, 3)) + assert p1 == p1_old + + assert p1.area == (-250*sqrt(5) + 1250)/(4*tan(pi/5)) + assert p1.length == 20*sqrt(-sqrt(5)/8 + Rational(5, 8)) + assert p1.scale(2, 2) == \ + RegularPolygon(p1.center, p1.radius*2, p1._n, p1.rotation) + assert RegularPolygon((0, 0), 1, 4).scale(2, 3) == \ + Polygon(Point(2, 0), Point(0, 3), Point(-2, 0), Point(0, -3)) + + assert repr(p1) == str(p1) + + # + # Angles + # + angles = p4.angles + assert feq(angles[Point(0, 0)].evalf(), Float("0.7853981633974483")) + assert feq(angles[Point(4, 4)].evalf(), Float("1.2490457723982544")) + assert feq(angles[Point(5, 2)].evalf(), Float("1.8925468811915388")) + assert feq(angles[Point(3, 0)].evalf(), Float("2.3561944901923449")) + + angles = p3.angles + assert feq(angles[Point(0, 0)].evalf(), Float("0.7853981633974483")) + assert feq(angles[Point(4, 4)].evalf(), Float("1.2490457723982544")) + assert feq(angles[Point(5, 2)].evalf(), Float("1.8925468811915388")) + assert feq(angles[Point(3, 0)].evalf(), Float("2.3561944901923449")) + + # https://github.com/sympy/sympy/issues/24885 + interior_angles_sum = sum(p13.angles.values()) + assert feq(interior_angles_sum, (len(p13.angles) - 2)*pi ) + interior_angles_sum = sum(p14.angles.values()) + assert feq(interior_angles_sum, (len(p14.angles) - 2)*pi ) + + # + # Triangle + # + p1 = Point(0, 0) + p2 = Point(5, 0) + p3 = Point(0, 5) + t1 = Triangle(p1, p2, p3) + t2 = Triangle(p1, p2, Point(Rational(5, 2), sqrt(Rational(75, 4)))) + t3 = Triangle(p1, Point(x1, 0), Point(0, x1)) + s1 = t1.sides + assert Triangle(p1, p2, p1) == Polygon(p1, p2, p1) == Segment(p1, p2) + raises(GeometryError, lambda: Triangle(Point(0, 0))) + + # Basic stuff + assert Triangle(p1, p1, p1) == p1 + assert Triangle(p2, p2*2, p2*3) == Segment(p2, p2*3) + assert t1.area == Rational(25, 2) + assert t1.is_right() + assert t2.is_right() is False + assert t3.is_right() + assert p1 in t1 + assert t1.sides[0] in t1 + assert Segment((0, 0), (1, 0)) in t1 + assert Point(5, 5) not in t2 + assert t1.is_convex() + assert feq(t1.angles[p1].evalf(), pi.evalf()/2) + + assert t1.is_equilateral() is False + assert t2.is_equilateral() + assert t3.is_equilateral() is False + assert are_similar(t1, t2) is False + assert are_similar(t1, t3) + assert are_similar(t2, t3) is False + assert t1.is_similar(Point(0, 0)) is False + assert t1.is_similar(t2) is False + + # Bisectors + bisectors = t1.bisectors() + assert bisectors[p1] == Segment( + p1, Point(Rational(5, 2), Rational(5, 2))) + assert t2.bisectors()[p2] == Segment( + Point(5, 0), Point(Rational(5, 4), 5*sqrt(3)/4)) + p4 = Point(0, x1) + assert t3.bisectors()[p4] == Segment(p4, Point(x1*(sqrt(2) - 1), 0)) + ic = (250 - 125*sqrt(2))/50 + assert t1.incenter == Point(ic, ic) + + # Inradius + assert t1.inradius == t1.incircle.radius == 5 - 5*sqrt(2)/2 + assert t2.inradius == t2.incircle.radius == 5*sqrt(3)/6 + assert t3.inradius == t3.incircle.radius == x1**2/((2 + sqrt(2))*Abs(x1)) + + # Exradius + assert t1.exradii[t1.sides[2]] == 5*sqrt(2)/2 + + # Excenters + assert t1.excenters[t1.sides[2]] == Point2D(25*sqrt(2), -5*sqrt(2)/2) + + # Circumcircle + assert t1.circumcircle.center == Point(2.5, 2.5) + + # Medians + Centroid + m = t1.medians + assert t1.centroid == Point(Rational(5, 3), Rational(5, 3)) + assert m[p1] == Segment(p1, Point(Rational(5, 2), Rational(5, 2))) + assert t3.medians[p1] == Segment(p1, Point(x1/2, x1/2)) + assert intersection(m[p1], m[p2], m[p3]) == [t1.centroid] + assert t1.medial == Triangle(Point(2.5, 0), Point(0, 2.5), Point(2.5, 2.5)) + + # Nine-point circle + assert t1.nine_point_circle == Circle(Point(2.5, 0), + Point(0, 2.5), Point(2.5, 2.5)) + assert t1.nine_point_circle == Circle(Point(0, 0), + Point(0, 2.5), Point(2.5, 2.5)) + + # Perpendicular + altitudes = t1.altitudes + assert altitudes[p1] == Segment(p1, Point(Rational(5, 2), Rational(5, 2))) + assert altitudes[p2].equals(s1[0]) + assert altitudes[p3] == s1[2] + assert t1.orthocenter == p1 + t = S('''Triangle( + Point(100080156402737/5000000000000, 79782624633431/500000000000), + Point(39223884078253/2000000000000, 156345163124289/1000000000000), + Point(31241359188437/1250000000000, 338338270939941/1000000000000000))''') + assert t.orthocenter == S('''Point(-780660869050599840216997''' + '''79471538701955848721853/80368430960602242240789074233100000000000000,''' + '''20151573611150265741278060334545897615974257/16073686192120448448157''' + '''8148466200000000000)''') + + # Ensure + assert len(intersection(*bisectors.values())) == 1 + assert len(intersection(*altitudes.values())) == 1 + assert len(intersection(*m.values())) == 1 + + # Distance + p1 = Polygon( + Point(0, 0), Point(1, 0), + Point(1, 1), Point(0, 1)) + p2 = Polygon( + Point(0, Rational(5)/4), Point(1, Rational(5)/4), + Point(1, Rational(9)/4), Point(0, Rational(9)/4)) + p3 = Polygon( + Point(1, 2), Point(2, 2), + Point(2, 1)) + p4 = Polygon( + Point(1, 1), Point(Rational(6)/5, 1), + Point(1, Rational(6)/5)) + pt1 = Point(half, half) + pt2 = Point(1, 1) + + '''Polygon to Point''' + assert p1.distance(pt1) == half + assert p1.distance(pt2) == 0 + assert p2.distance(pt1) == Rational(3)/4 + assert p3.distance(pt2) == sqrt(2)/2 + + '''Polygon to Polygon''' + # p1.distance(p2) emits a warning + with warns(UserWarning, \ + match="Polygons may intersect producing erroneous output"): + assert p1.distance(p2) == half/2 + + assert p1.distance(p3) == sqrt(2)/2 + + # p3.distance(p4) emits a warning + with warns(UserWarning, \ + match="Polygons may intersect producing erroneous output"): + assert p3.distance(p4) == (sqrt(2)/2 - sqrt(Rational(2)/25)/2) + + +def test_convex_hull(): + p = [Point(-5, -1), Point(-2, 1), Point(-2, -1), Point(-1, -3), \ + Point(0, 0), Point(1, 1), Point(2, 2), Point(2, -1), Point(3, 1), \ + Point(4, -1), Point(6, 2)] + ch = Polygon(p[0], p[3], p[9], p[10], p[6], p[1]) + #test handling of duplicate points + p.append(p[3]) + + #more than 3 collinear points + another_p = [Point(-45, -85), Point(-45, 85), Point(-45, 26), \ + Point(-45, -24)] + ch2 = Segment(another_p[0], another_p[1]) + + assert convex_hull(*another_p) == ch2 + assert convex_hull(*p) == ch + assert convex_hull(p[0]) == p[0] + assert convex_hull(p[0], p[1]) == Segment(p[0], p[1]) + + # no unique points + assert convex_hull(*[p[-1]]*3) == p[-1] + + # collection of items + assert convex_hull(*[Point(0, 0), \ + Segment(Point(1, 0), Point(1, 1)), \ + RegularPolygon(Point(2, 0), 2, 4)]) == \ + Polygon(Point(0, 0), Point(2, -2), Point(4, 0), Point(2, 2)) + + +def test_encloses(): + # square with a dimpled left side + s = Polygon(Point(0, 0), Point(1, 0), Point(1, 1), Point(0, 1), \ + Point(S.Half, S.Half)) + # the following is True if the polygon isn't treated as closing on itself + assert s.encloses(Point(0, S.Half)) is False + assert s.encloses(Point(S.Half, S.Half)) is False # it's a vertex + assert s.encloses(Point(Rational(3, 4), S.Half)) is True + + +def test_triangle_kwargs(): + assert Triangle(sss=(3, 4, 5)) == \ + Triangle(Point(0, 0), Point(3, 0), Point(3, 4)) + assert Triangle(asa=(30, 2, 30)) == \ + Triangle(Point(0, 0), Point(2, 0), Point(1, sqrt(3)/3)) + assert Triangle(sas=(1, 45, 2)) == \ + Triangle(Point(0, 0), Point(2, 0), Point(sqrt(2)/2, sqrt(2)/2)) + assert Triangle(sss=(1, 2, 5)) is None + assert deg(rad(180)) == 180 + + +def test_transform(): + pts = [Point(0, 0), Point(S.Half, Rational(1, 4)), Point(1, 1)] + pts_out = [Point(-4, -10), Point(-3, Rational(-37, 4)), Point(-2, -7)] + assert Triangle(*pts).scale(2, 3, (4, 5)) == Triangle(*pts_out) + assert RegularPolygon((0, 0), 1, 4).scale(2, 3, (4, 5)) == \ + Polygon(Point(-2, -10), Point(-4, -7), Point(-6, -10), Point(-4, -13)) + # Checks for symmetric scaling + assert RegularPolygon((0, 0), 1, 4).scale(2, 2) == \ + RegularPolygon(Point2D(0, 0), 2, 4, 0) + +def test_reflect(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + b = Symbol('b') + m = Symbol('m') + l = Line((0, b), slope=m) + p = Point(x, y) + r = p.reflect(l) + dp = l.perpendicular_segment(p).length + dr = l.perpendicular_segment(r).length + + assert verify_numerically(dp, dr) + + assert Polygon((1, 0), (2, 0), (2, 2)).reflect(Line((3, 0), slope=oo)) \ + == Triangle(Point(5, 0), Point(4, 0), Point(4, 2)) + assert Polygon((1, 0), (2, 0), (2, 2)).reflect(Line((0, 3), slope=oo)) \ + == Triangle(Point(-1, 0), Point(-2, 0), Point(-2, 2)) + assert Polygon((1, 0), (2, 0), (2, 2)).reflect(Line((0, 3), slope=0)) \ + == Triangle(Point(1, 6), Point(2, 6), Point(2, 4)) + assert Polygon((1, 0), (2, 0), (2, 2)).reflect(Line((3, 0), slope=0)) \ + == Triangle(Point(1, 0), Point(2, 0), Point(2, -2)) + +def test_bisectors(): + p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) + p = Polygon(Point(0, 0), Point(2, 0), Point(1, 1), Point(0, 3)) + q = Polygon(Point(1, 0), Point(2, 0), Point(3, 3), Point(-1, 5)) + poly = Polygon(Point(3, 4), Point(0, 0), Point(8, 7), Point(-1, 1), Point(19, -19)) + t = Triangle(p1, p2, p3) + assert t.bisectors()[p2] == Segment(Point(1, 0), Point(0, sqrt(2) - 1)) + assert p.bisectors()[Point2D(0, 3)] == Ray2D(Point2D(0, 3), \ + Point2D(sin(acos(2*sqrt(5)/5)/2), 3 - cos(acos(2*sqrt(5)/5)/2))) + assert q.bisectors()[Point2D(-1, 5)] == \ + Ray2D(Point2D(-1, 5), Point2D(-1 + sqrt(29)*(5*sin(acos(9*sqrt(145)/145)/2) + \ + 2*cos(acos(9*sqrt(145)/145)/2))/29, sqrt(29)*(-5*cos(acos(9*sqrt(145)/145)/2) + \ + 2*sin(acos(9*sqrt(145)/145)/2))/29 + 5)) + assert poly.bisectors()[Point2D(-1, 1)] == Ray2D(Point2D(-1, 1), \ + Point2D(-1 + sin(acos(sqrt(26)/26)/2 + pi/4), 1 - sin(-acos(sqrt(26)/26)/2 + pi/4))) + +def test_incenter(): + assert Triangle(Point(0, 0), Point(1, 0), Point(0, 1)).incenter \ + == Point(1 - sqrt(2)/2, 1 - sqrt(2)/2) + +def test_inradius(): + assert Triangle(Point(0, 0), Point(4, 0), Point(0, 3)).inradius == 1 + +def test_incircle(): + assert Triangle(Point(0, 0), Point(2, 0), Point(0, 2)).incircle \ + == Circle(Point(2 - sqrt(2), 2 - sqrt(2)), 2 - sqrt(2)) + +def test_exradii(): + t = Triangle(Point(0, 0), Point(6, 0), Point(0, 2)) + assert t.exradii[t.sides[2]] == (-2 + sqrt(10)) + +def test_medians(): + t = Triangle(Point(0, 0), Point(1, 0), Point(0, 1)) + assert t.medians[Point(0, 0)] == Segment(Point(0, 0), Point(S.Half, S.Half)) + +def test_medial(): + assert Triangle(Point(0, 0), Point(1, 0), Point(0, 1)).medial \ + == Triangle(Point(S.Half, 0), Point(S.Half, S.Half), Point(0, S.Half)) + +def test_nine_point_circle(): + assert Triangle(Point(0, 0), Point(1, 0), Point(0, 1)).nine_point_circle \ + == Circle(Point2D(Rational(1, 4), Rational(1, 4)), sqrt(2)/4) + +def test_eulerline(): + assert Triangle(Point(0, 0), Point(1, 0), Point(0, 1)).eulerline \ + == Line(Point2D(0, 0), Point2D(S.Half, S.Half)) + assert Triangle(Point(0, 0), Point(10, 0), Point(5, 5*sqrt(3))).eulerline \ + == Point2D(5, 5*sqrt(3)/3) + assert Triangle(Point(4, -6), Point(4, -1), Point(-3, 3)).eulerline \ + == Line(Point2D(Rational(64, 7), 3), Point2D(Rational(-29, 14), Rational(-7, 2))) + +def test_intersection(): + poly1 = Triangle(Point(0, 0), Point(1, 0), Point(0, 1)) + poly2 = Polygon(Point(0, 1), Point(-5, 0), + Point(0, -4), Point(0, Rational(1, 5)), + Point(S.Half, -0.1), Point(1, 0), Point(0, 1)) + + assert poly1.intersection(poly2) == [Point2D(Rational(1, 3), 0), + Segment(Point(0, Rational(1, 5)), Point(0, 0)), + Segment(Point(1, 0), Point(0, 1))] + assert poly2.intersection(poly1) == [Point(Rational(1, 3), 0), + Segment(Point(0, 0), Point(0, Rational(1, 5))), + Segment(Point(1, 0), Point(0, 1))] + assert poly1.intersection(Point(0, 0)) == [Point(0, 0)] + assert poly1.intersection(Point(-12, -43)) == [] + assert poly2.intersection(Line((-12, 0), (12, 0))) == [Point(-5, 0), + Point(0, 0), Point(Rational(1, 3), 0), Point(1, 0)] + assert poly2.intersection(Line((-12, 12), (12, 12))) == [] + assert poly2.intersection(Ray((-3, 4), (1, 0))) == [Segment(Point(1, 0), + Point(0, 1))] + assert poly2.intersection(Circle((0, -1), 1)) == [Point(0, -2), + Point(0, 0)] + assert poly1.intersection(poly1) == [Segment(Point(0, 0), Point(1, 0)), + Segment(Point(0, 1), Point(0, 0)), Segment(Point(1, 0), Point(0, 1))] + assert poly2.intersection(poly2) == [Segment(Point(-5, 0), Point(0, -4)), + Segment(Point(0, -4), Point(0, Rational(1, 5))), + Segment(Point(0, Rational(1, 5)), Point(S.Half, Rational(-1, 10))), + Segment(Point(0, 1), Point(-5, 0)), + Segment(Point(S.Half, Rational(-1, 10)), Point(1, 0)), + Segment(Point(1, 0), Point(0, 1))] + assert poly2.intersection(Triangle(Point(0, 1), Point(1, 0), Point(-1, 1))) \ + == [Point(Rational(-5, 7), Rational(6, 7)), Segment(Point2D(0, 1), Point(1, 0))] + assert poly1.intersection(RegularPolygon((-12, -15), 3, 3)) == [] + + +def test_parameter_value(): + t = Symbol('t') + sq = Polygon((0, 0), (0, 1), (1, 1), (1, 0)) + assert sq.parameter_value((0.5, 1), t) == {t: Rational(3, 8)} + q = Polygon((0, 0), (2, 1), (2, 4), (4, 0)) + assert q.parameter_value((4, 0), t) == {t: -6 + 3*sqrt(5)} # ~= 0.708 + + raises(ValueError, lambda: sq.parameter_value((5, 6), t)) + raises(ValueError, lambda: sq.parameter_value(Circle(Point(0, 0), 1), t)) + + +def test_issue_12966(): + poly = Polygon(Point(0, 0), Point(0, 10), Point(5, 10), Point(5, 5), + Point(10, 5), Point(10, 0)) + t = Symbol('t') + pt = poly.arbitrary_point(t) + DELTA = 5/poly.perimeter + assert [pt.subs(t, DELTA*i) for i in range(int(1/DELTA))] == [ + Point(0, 0), Point(0, 5), Point(0, 10), Point(5, 10), + Point(5, 5), Point(10, 5), Point(10, 0), Point(5, 0)] + + +def test_second_moment_of_area(): + x, y = symbols('x, y') + # triangle + p1, p2, p3 = [(0, 0), (4, 0), (0, 2)] + p = (0, 0) + # equation of hypotenuse + eq_y = (1-x/4)*2 + I_yy = integrate((x**2) * (integrate(1, (y, 0, eq_y))), (x, 0, 4)) + I_xx = integrate(1 * (integrate(y**2, (y, 0, eq_y))), (x, 0, 4)) + I_xy = integrate(x * (integrate(y, (y, 0, eq_y))), (x, 0, 4)) + + triangle = Polygon(p1, p2, p3) + + assert (I_xx - triangle.second_moment_of_area(p)[0]) == 0 + assert (I_yy - triangle.second_moment_of_area(p)[1]) == 0 + assert (I_xy - triangle.second_moment_of_area(p)[2]) == 0 + + # rectangle + p1, p2, p3, p4=[(0, 0), (4, 0), (4, 2), (0, 2)] + I_yy = integrate((x**2) * integrate(1, (y, 0, 2)), (x, 0, 4)) + I_xx = integrate(1 * integrate(y**2, (y, 0, 2)), (x, 0, 4)) + I_xy = integrate(x * integrate(y, (y, 0, 2)), (x, 0, 4)) + + rectangle = Polygon(p1, p2, p3, p4) + + assert (I_xx - rectangle.second_moment_of_area(p)[0]) == 0 + assert (I_yy - rectangle.second_moment_of_area(p)[1]) == 0 + assert (I_xy - rectangle.second_moment_of_area(p)[2]) == 0 + + + r = RegularPolygon(Point(0, 0), 5, 3) + assert r.second_moment_of_area() == (1875*sqrt(3)/S(32), 1875*sqrt(3)/S(32), 0) + + +def test_first_moment(): + a, b = symbols('a, b', positive=True) + # rectangle + p1 = Polygon((0, 0), (a, 0), (a, b), (0, b)) + assert p1.first_moment_of_area() == (a*b**2/8, a**2*b/8) + assert p1.first_moment_of_area((a/3, b/4)) == (-3*a*b**2/32, -a**2*b/9) + + p1 = Polygon((0, 0), (40, 0), (40, 30), (0, 30)) + assert p1.first_moment_of_area() == (4500, 6000) + + # triangle + p2 = Polygon((0, 0), (a, 0), (a/2, b)) + assert p2.first_moment_of_area() == (4*a*b**2/81, a**2*b/24) + assert p2.first_moment_of_area((a/8, b/6)) == (-25*a*b**2/648, -5*a**2*b/768) + + p2 = Polygon((0, 0), (12, 0), (12, 30)) + assert p2.first_moment_of_area() == (S(1600)/3, -S(640)/3) + + +def test_section_modulus_and_polar_second_moment_of_area(): + a, b = symbols('a, b', positive=True) + x, y = symbols('x, y') + rectangle = Polygon((0, b), (0, 0), (a, 0), (a, b)) + assert rectangle.section_modulus(Point(x, y)) == (a*b**3/12/(-b/2 + y), a**3*b/12/(-a/2 + x)) + assert rectangle.polar_second_moment_of_area() == a**3*b/12 + a*b**3/12 + + convex = RegularPolygon((0, 0), 1, 6) + assert convex.section_modulus() == (Rational(5, 8), sqrt(3)*Rational(5, 16)) + assert convex.polar_second_moment_of_area() == 5*sqrt(3)/S(8) + + concave = Polygon((0, 0), (1, 8), (3, 4), (4, 6), (7, 1)) + assert concave.section_modulus() == (Rational(-6371, 429), Rational(-9778, 519)) + assert concave.polar_second_moment_of_area() == Rational(-38669, 252) + + +def test_cut_section(): + # concave polygon + p = Polygon((-1, -1), (1, Rational(5, 2)), (2, 1), (3, Rational(5, 2)), (4, 2), (5, 3), (-1, 3)) + l = Line((0, 0), (Rational(9, 2), 3)) + p1 = p.cut_section(l)[0] + p2 = p.cut_section(l)[1] + assert p1 == Polygon( + Point2D(Rational(-9, 13), Rational(-6, 13)), Point2D(1, Rational(5, 2)), Point2D(Rational(24, 13), Rational(16, 13)), + Point2D(Rational(12, 5), Rational(8, 5)), Point2D(3, Rational(5, 2)), Point2D(Rational(24, 7), Rational(16, 7)), + Point2D(Rational(9, 2), 3), Point2D(-1, 3), Point2D(-1, Rational(-2, 3))) + assert p2 == Polygon(Point2D(-1, -1), Point2D(Rational(-9, 13), Rational(-6, 13)), Point2D(Rational(24, 13), Rational(16, 13)), + Point2D(2, 1), Point2D(Rational(12, 5), Rational(8, 5)), Point2D(Rational(24, 7), Rational(16, 7)), Point2D(4, 2), Point2D(5, 3), + Point2D(Rational(9, 2), 3), Point2D(-1, Rational(-2, 3))) + + # convex polygon + p = RegularPolygon(Point2D(0, 0), 6, 6) + s = p.cut_section(Line((0, 0), slope=1)) + assert s[0] == Polygon(Point2D(-3*sqrt(3) + 9, -3*sqrt(3) + 9), Point2D(3, 3*sqrt(3)), + Point2D(-3, 3*sqrt(3)), Point2D(-6, 0), Point2D(-9 + 3*sqrt(3), -9 + 3*sqrt(3))) + assert s[1] == Polygon(Point2D(6, 0), Point2D(-3*sqrt(3) + 9, -3*sqrt(3) + 9), + Point2D(-9 + 3*sqrt(3), -9 + 3*sqrt(3)), Point2D(-3, -3*sqrt(3)), Point2D(3, -3*sqrt(3))) + + # case where line does not intersects but coincides with the edge of polygon + a, b = 20, 10 + t1, t2, t3, t4 = [(0, b), (0, 0), (a, 0), (a, b)] + p = Polygon(t1, t2, t3, t4) + p1, p2 = p.cut_section(Line((0, b), slope=0)) + assert p1 == None + assert p2 == Polygon(Point2D(0, 10), Point2D(0, 0), Point2D(20, 0), Point2D(20, 10)) + + p3, p4 = p.cut_section(Line((0, 0), slope=0)) + assert p3 == Polygon(Point2D(0, 10), Point2D(0, 0), Point2D(20, 0), Point2D(20, 10)) + assert p4 == None + + # case where the line does not intersect with a polygon at all + raises(ValueError, lambda: p.cut_section(Line((0, a), slope=0))) + +def test_type_of_triangle(): + # Isoceles triangle + p1 = Polygon(Point(0, 0), Point(5, 0), Point(2, 4)) + assert p1.is_isosceles() == True + assert p1.is_scalene() == False + assert p1.is_equilateral() == False + + # Scalene triangle + p2 = Polygon (Point(0, 0), Point(0, 2), Point(4, 0)) + assert p2.is_isosceles() == False + assert p2.is_scalene() == True + assert p2.is_equilateral() == False + + # Equilateral triangle + p3 = Polygon(Point(0, 0), Point(6, 0), Point(3, sqrt(27))) + assert p3.is_isosceles() == True + assert p3.is_scalene() == False + assert p3.is_equilateral() == True + +def test_do_poly_distance(): + # Non-intersecting polygons + square1 = Polygon (Point(0, 0), Point(0, 1), Point(1, 1), Point(1, 0)) + triangle1 = Polygon(Point(1, 2), Point(2, 2), Point(2, 1)) + assert square1._do_poly_distance(triangle1) == sqrt(2)/2 + + # Polygons which sides intersect + square2 = Polygon(Point(1, 0), Point(2, 0), Point(2, 1), Point(1, 1)) + with warns(UserWarning, \ + match="Polygons may intersect producing erroneous output", test_stacklevel=False): + assert square1._do_poly_distance(square2) == 0 + + # Polygons which bodies intersect + triangle2 = Polygon(Point(0, -1), Point(2, -1), Point(S.Half, S.Half)) + with warns(UserWarning, \ + match="Polygons may intersect producing erroneous output", test_stacklevel=False): + assert triangle2._do_poly_distance(square1) == 0 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_util.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_util.py new file mode 100644 index 0000000000000000000000000000000000000000..da52a795a9383c6438ca06303e8ae6506dccdc65 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/tests/test_util.py @@ -0,0 +1,170 @@ +import pytest +from sympy.core.numbers import Float +from sympy.core.function import (Derivative, Function) +from sympy.core.singleton import S +from sympy.core.symbol import Symbol +from sympy.functions import exp, cos, sin, tan, cosh, sinh +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.geometry import Point, Point2D, Line, Polygon, Segment, convex_hull,\ + intersection, centroid, Point3D, Line3D, Ray, Ellipse +from sympy.geometry.util import idiff, closest_points, farthest_points, _ordered_points, are_coplanar +from sympy.solvers.solvers import solve +from sympy.testing.pytest import raises + + +def test_idiff(): + x = Symbol('x', real=True) + y = Symbol('y', real=True) + t = Symbol('t', real=True) + f = Function('f') + g = Function('g') + # the use of idiff in ellipse also provides coverage + circ = x**2 + y**2 - 4 + ans = -3*x*(x**2/y**2 + 1)/y**3 + assert ans == idiff(circ, y, x, 3), idiff(circ, y, x, 3) + assert ans == idiff(circ, [y], x, 3) + assert idiff(circ, y, x, 3) == ans + explicit = 12*x/sqrt(-x**2 + 4)**5 + assert ans.subs(y, solve(circ, y)[0]).equals(explicit) + assert True in [sol.diff(x, 3).equals(explicit) for sol in solve(circ, y)] + assert idiff(x + t + y, [y, t], x) == -Derivative(t, x) - 1 + assert idiff(f(x) * exp(f(x)) - x * exp(x), f(x), x) == (x + 1)*exp(x)*exp(-f(x))/(f(x) + 1) + assert idiff(f(x) - y * exp(x), [f(x), y], x) == (y + Derivative(y, x))*exp(x) + assert idiff(f(x) - y * exp(x), [y, f(x)], x) == -y + Derivative(f(x), x)*exp(-x) + assert idiff(f(x) - g(x), [f(x), g(x)], x) == Derivative(g(x), x) + # this should be fast + fxy = y - (-10*(-sin(x) + 1/x)**2 + tan(x)**2 + 2*cosh(x/10)) + assert idiff(fxy, y, x) == -20*sin(x)*cos(x) + 2*tan(x)**3 + \ + 2*tan(x) + sinh(x/10)/5 + 20*cos(x)/x - 20*sin(x)/x**2 + 20/x**3 + + +def test_intersection(): + assert intersection(Point(0, 0)) == [] + raises(TypeError, lambda: intersection(Point(0, 0), 3)) + assert intersection( + Segment((0, 0), (2, 0)), + Segment((-1, 0), (1, 0)), + Line((0, 0), (0, 1)), pairwise=True) == [ + Point(0, 0), Segment((0, 0), (1, 0))] + assert intersection( + Line((0, 0), (0, 1)), + Segment((0, 0), (2, 0)), + Segment((-1, 0), (1, 0)), pairwise=True) == [ + Point(0, 0), Segment((0, 0), (1, 0))] + assert intersection( + Line((0, 0), (0, 1)), + Segment((0, 0), (2, 0)), + Segment((-1, 0), (1, 0)), + Line((0, 0), slope=1), pairwise=True) == [ + Point(0, 0), Segment((0, 0), (1, 0))] + R = 4.0 + c = intersection( + Ray(Point2D(0.001, -1), + Point2D(0.0008, -1.7)), + Ellipse(center=Point2D(0, 0), hradius=R, vradius=2.0), pairwise=True)[0].coordinates + assert c == pytest.approx( + Point2D(0.000714285723396502, -1.99999996811224, evaluate=False).coordinates) + # check this is responds to a lower precision parameter + R = Float(4, 5) + c2 = intersection( + Ray(Point2D(0.001, -1), + Point2D(0.0008, -1.7)), + Ellipse(center=Point2D(0, 0), hradius=R, vradius=2.0), pairwise=True)[0].coordinates + assert c2 == pytest.approx( + Point2D(0.000714285723396502, -1.99999996811224, evaluate=False).coordinates) + assert c[0]._prec == 53 + assert c2[0]._prec == 20 + + +def test_convex_hull(): + raises(TypeError, lambda: convex_hull(Point(0, 0), 3)) + points = [(1, -1), (1, -2), (3, -1), (-5, -2), (15, -4)] + assert convex_hull(*points, **{"polygon": False}) == ( + [Point2D(-5, -2), Point2D(1, -1), Point2D(3, -1), Point2D(15, -4)], + [Point2D(-5, -2), Point2D(15, -4)]) + + +def test_centroid(): + p = Polygon((0, 0), (10, 0), (10, 10)) + q = p.translate(0, 20) + assert centroid(p, q) == Point(20, 40)/3 + p = Segment((0, 0), (2, 0)) + q = Segment((0, 0), (2, 2)) + assert centroid(p, q) == Point(1, -sqrt(2) + 2) + assert centroid(Point(0, 0), Point(2, 0)) == Point(2, 0)/2 + assert centroid(Point(0, 0), Point(0, 0), Point(2, 0)) == Point(2, 0)/3 + + +def test_farthest_points_closest_points(): + from sympy.core.random import randint + from sympy.utilities.iterables import subsets + + for how in (min, max): + if how == min: + func = closest_points + else: + func = farthest_points + + raises(ValueError, lambda: func(Point2D(0, 0), Point2D(0, 0))) + + # 3rd pt dx is close and pt is closer to 1st pt + p1 = [Point2D(0, 0), Point2D(3, 0), Point2D(1, 1)] + # 3rd pt dx is close and pt is closer to 2nd pt + p2 = [Point2D(0, 0), Point2D(3, 0), Point2D(2, 1)] + # 3rd pt dx is close and but pt is not closer + p3 = [Point2D(0, 0), Point2D(3, 0), Point2D(1, 10)] + # 3rd pt dx is not closer and it's closer to 2nd pt + p4 = [Point2D(0, 0), Point2D(3, 0), Point2D(4, 0)] + # 3rd pt dx is not closer and it's closer to 1st pt + p5 = [Point2D(0, 0), Point2D(3, 0), Point2D(-1, 0)] + # duplicate point doesn't affect outcome + dup = [Point2D(0, 0), Point2D(3, 0), Point2D(3, 0), Point2D(-1, 0)] + # symbolic + x = Symbol('x', positive=True) + s = [Point2D(a) for a in ((x, 1), (x + 3, 2), (x + 2, 2))] + + for points in (p1, p2, p3, p4, p5, dup, s): + d = how(i.distance(j) for i, j in subsets(set(points), 2)) + ans = a, b = list(func(*points))[0] + assert a.distance(b) == d + assert ans == _ordered_points(ans) + + # if the following ever fails, the above tests were not sufficient + # and the logical error in the routine should be fixed + points = set() + while len(points) != 7: + points.add(Point2D(randint(1, 100), randint(1, 100))) + points = list(points) + d = how(i.distance(j) for i, j in subsets(points, 2)) + ans = a, b = list(func(*points))[0] + assert a.distance(b) == d + assert ans == _ordered_points(ans) + + # equidistant points + a, b, c = ( + Point2D(0, 0), Point2D(1, 0), Point2D(S.Half, sqrt(3)/2)) + ans = {_ordered_points((i, j)) + for i, j in subsets((a, b, c), 2)} + assert closest_points(b, c, a) == ans + assert farthest_points(b, c, a) == ans + + # unique to farthest + points = [(1, 1), (1, 2), (3, 1), (-5, 2), (15, 4)] + assert farthest_points(*points) == { + (Point2D(-5, 2), Point2D(15, 4))} + points = [(1, -1), (1, -2), (3, -1), (-5, -2), (15, -4)] + assert farthest_points(*points) == { + (Point2D(-5, -2), Point2D(15, -4))} + assert farthest_points((1, 1), (0, 0)) == { + (Point2D(0, 0), Point2D(1, 1))} + raises(ValueError, lambda: farthest_points((1, 1))) + + +def test_are_coplanar(): + a = Line3D(Point3D(5, 0, 0), Point3D(1, -1, 1)) + b = Line3D(Point3D(0, -2, 0), Point3D(3, 1, 1)) + c = Line3D(Point3D(0, -1, 0), Point3D(5, -1, 9)) + d = Line(Point2D(0, 3), Point2D(1, 5)) + + assert are_coplanar(a, b, c) == False + assert are_coplanar(a, d) == False diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/util.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/util.py new file mode 100644 index 0000000000000000000000000000000000000000..1d8fb77550f2faea8185ff0c373b5f1680e623ec --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/geometry/util.py @@ -0,0 +1,731 @@ +"""Utility functions for geometrical entities. + +Contains +======== +intersection +convex_hull +closest_points +farthest_points +are_coplanar +are_similar + +""" + +from collections import deque +from math import sqrt as _sqrt + +from sympy import nsimplify +from .entity import GeometryEntity +from .exceptions import GeometryError +from .point import Point, Point2D, Point3D +from sympy.core.containers import OrderedSet +from sympy.core.exprtools import factor_terms +from sympy.core.function import Function, expand_mul +from sympy.core.numbers import Float +from sympy.core.sorting import ordered +from sympy.core.symbol import Symbol +from sympy.core.singleton import S +from sympy.polys.polytools import cancel +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.utilities.iterables import is_sequence + +from mpmath.libmp.libmpf import prec_to_dps + + +def find(x, equation): + """ + Checks whether a Symbol matching ``x`` is present in ``equation`` + or not. If present, the matching symbol is returned, else a + ValueError is raised. If ``x`` is a string the matching symbol + will have the same name; if ``x`` is a Symbol then it will be + returned if found. + + Examples + ======== + + >>> from sympy.geometry.util import find + >>> from sympy import Dummy + >>> from sympy.abc import x + >>> find('x', x) + x + >>> find('x', Dummy('x')) + _x + + The dummy symbol is returned since it has a matching name: + + >>> _.name == 'x' + True + >>> find(x, Dummy('x')) + Traceback (most recent call last): + ... + ValueError: could not find x + """ + + free = equation.free_symbols + xs = [i for i in free if (i.name if isinstance(x, str) else i) == x] + if not xs: + raise ValueError('could not find %s' % x) + if len(xs) != 1: + raise ValueError('ambiguous %s' % x) + return xs[0] + + +def _ordered_points(p): + """Return the tuple of points sorted numerically according to args""" + return tuple(sorted(p, key=lambda x: x.args)) + + +def are_coplanar(*e): + """ Returns True if the given entities are coplanar otherwise False + + Parameters + ========== + + e: entities to be checked for being coplanar + + Returns + ======= + + Boolean + + Examples + ======== + + >>> from sympy import Point3D, Line3D + >>> from sympy.geometry.util import are_coplanar + >>> a = Line3D(Point3D(5, 0, 0), Point3D(1, -1, 1)) + >>> b = Line3D(Point3D(0, -2, 0), Point3D(3, 1, 1)) + >>> c = Line3D(Point3D(0, -1, 0), Point3D(5, -1, 9)) + >>> are_coplanar(a, b, c) + False + + """ + from .line import LinearEntity3D + from .plane import Plane + # XXX update tests for coverage + + e = set(e) + # first work with a Plane if present + for i in list(e): + if isinstance(i, Plane): + e.remove(i) + return all(p.is_coplanar(i) for p in e) + + if all(isinstance(i, Point3D) for i in e): + if len(e) < 3: + return False + + # remove pts that are collinear with 2 pts + a, b = e.pop(), e.pop() + for i in list(e): + if Point3D.are_collinear(a, b, i): + e.remove(i) + + if not e: + return False + else: + # define a plane + p = Plane(a, b, e.pop()) + for i in e: + if i not in p: + return False + return True + else: + pt3d = [] + for i in e: + if isinstance(i, Point3D): + pt3d.append(i) + elif isinstance(i, LinearEntity3D): + pt3d.extend(i.args) + elif isinstance(i, GeometryEntity): # XXX we should have a GeometryEntity3D class so we can tell the difference between 2D and 3D -- here we just want to deal with 2D objects; if new 3D objects are encountered that we didn't handle above, an error should be raised + # all 2D objects have some Point that defines them; so convert those points to 3D pts by making z=0 + for p in i.args: + if isinstance(p, Point): + pt3d.append(Point3D(*(p.args + (0,)))) + return are_coplanar(*pt3d) + + +def are_similar(e1, e2): + """Are two geometrical entities similar. + + Can one geometrical entity be uniformly scaled to the other? + + Parameters + ========== + + e1 : GeometryEntity + e2 : GeometryEntity + + Returns + ======= + + are_similar : boolean + + Raises + ====== + + GeometryError + When `e1` and `e2` cannot be compared. + + Notes + ===== + + If the two objects are equal then they are similar. + + See Also + ======== + + sympy.geometry.entity.GeometryEntity.is_similar + + Examples + ======== + + >>> from sympy import Point, Circle, Triangle, are_similar + >>> c1, c2 = Circle(Point(0, 0), 4), Circle(Point(1, 4), 3) + >>> t1 = Triangle(Point(0, 0), Point(1, 0), Point(0, 1)) + >>> t2 = Triangle(Point(0, 0), Point(2, 0), Point(0, 2)) + >>> t3 = Triangle(Point(0, 0), Point(3, 0), Point(0, 1)) + >>> are_similar(t1, t2) + True + >>> are_similar(t1, t3) + False + + """ + if e1 == e2: + return True + is_similar1 = getattr(e1, 'is_similar', None) + if is_similar1: + return is_similar1(e2) + is_similar2 = getattr(e2, 'is_similar', None) + if is_similar2: + return is_similar2(e1) + n1 = e1.__class__.__name__ + n2 = e2.__class__.__name__ + raise GeometryError( + "Cannot test similarity between %s and %s" % (n1, n2)) + + +def centroid(*args): + """Find the centroid (center of mass) of the collection containing only Points, + Segments or Polygons. The centroid is the weighted average of the individual centroid + where the weights are the lengths (of segments) or areas (of polygons). + Overlapping regions will add to the weight of that region. + + If there are no objects (or a mixture of objects) then None is returned. + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.line.Segment, + sympy.geometry.polygon.Polygon + + Examples + ======== + + >>> from sympy import Point, Segment, Polygon + >>> from sympy.geometry.util import centroid + >>> p = Polygon((0, 0), (10, 0), (10, 10)) + >>> q = p.translate(0, 20) + >>> p.centroid, q.centroid + (Point2D(20/3, 10/3), Point2D(20/3, 70/3)) + >>> centroid(p, q) + Point2D(20/3, 40/3) + >>> p, q = Segment((0, 0), (2, 0)), Segment((0, 0), (2, 2)) + >>> centroid(p, q) + Point2D(1, 2 - sqrt(2)) + >>> centroid(Point(0, 0), Point(2, 0)) + Point2D(1, 0) + + Stacking 3 polygons on top of each other effectively triples the + weight of that polygon: + + >>> p = Polygon((0, 0), (1, 0), (1, 1), (0, 1)) + >>> q = Polygon((1, 0), (3, 0), (3, 1), (1, 1)) + >>> centroid(p, q) + Point2D(3/2, 1/2) + >>> centroid(p, p, p, q) # centroid x-coord shifts left + Point2D(11/10, 1/2) + + Stacking the squares vertically above and below p has the same + effect: + + >>> centroid(p, p.translate(0, 1), p.translate(0, -1), q) + Point2D(11/10, 1/2) + + """ + from .line import Segment + from .polygon import Polygon + if args: + if all(isinstance(g, Point) for g in args): + c = Point(0, 0) + for g in args: + c += g + den = len(args) + elif all(isinstance(g, Segment) for g in args): + c = Point(0, 0) + L = 0 + for g in args: + l = g.length + c += g.midpoint*l + L += l + den = L + elif all(isinstance(g, Polygon) for g in args): + c = Point(0, 0) + A = 0 + for g in args: + a = g.area + c += g.centroid*a + A += a + den = A + c /= den + return c.func(*[i.simplify() for i in c.args]) + + +def closest_points(*args): + """Return the subset of points from a set of points that were + the closest to each other in the 2D plane. + + Parameters + ========== + + args + A collection of Points on 2D plane. + + Notes + ===== + + This can only be performed on a set of points whose coordinates can + be ordered on the number line. If there are no ties then a single + pair of Points will be in the set. + + Examples + ======== + + >>> from sympy import closest_points, Triangle + >>> Triangle(sss=(3, 4, 5)).args + (Point2D(0, 0), Point2D(3, 0), Point2D(3, 4)) + >>> closest_points(*_) + {(Point2D(0, 0), Point2D(3, 0))} + + References + ========== + + .. [1] https://www.cs.mcgill.ca/~cs251/ClosestPair/ClosestPairPS.html + + .. [2] Sweep line algorithm + https://en.wikipedia.org/wiki/Sweep_line_algorithm + + """ + p = [Point2D(i) for i in set(args)] + if len(p) < 2: + raise ValueError('At least 2 distinct points must be given.') + + try: + p.sort(key=lambda x: x.args) + except TypeError: + raise ValueError("The points could not be sorted.") + + if not all(i.is_Rational for j in p for i in j.args): + def hypot(x, y): + arg = x*x + y*y + if arg.is_Rational: + return _sqrt(arg) + return sqrt(arg) + else: + from math import hypot + + rv = [(0, 1)] + best_dist = hypot(p[1].x - p[0].x, p[1].y - p[0].y) + left = 0 + box = deque([0, 1]) + for i in range(2, len(p)): + while left < i and p[i][0] - p[left][0] > best_dist: + box.popleft() + left += 1 + + for j in box: + d = hypot(p[i].x - p[j].x, p[i].y - p[j].y) + if d < best_dist: + rv = [(j, i)] + elif d == best_dist: + rv.append((j, i)) + else: + continue + best_dist = d + box.append(i) + + return {tuple([p[i] for i in pair]) for pair in rv} + + +def convex_hull(*args, polygon=True): + """The convex hull surrounding the Points contained in the list of entities. + + Parameters + ========== + + args : a collection of Points, Segments and/or Polygons + + Optional parameters + =================== + + polygon : Boolean. If True, returns a Polygon, if false a tuple, see below. + Default is True. + + Returns + ======= + + convex_hull : Polygon if ``polygon`` is True else as a tuple `(U, L)` where + ``L`` and ``U`` are the lower and upper hulls, respectively. + + Notes + ===== + + This can only be performed on a set of points whose coordinates can + be ordered on the number line. + + See Also + ======== + + sympy.geometry.point.Point, sympy.geometry.polygon.Polygon + + Examples + ======== + + >>> from sympy import convex_hull + >>> points = [(1, 1), (1, 2), (3, 1), (-5, 2), (15, 4)] + >>> convex_hull(*points) + Polygon(Point2D(-5, 2), Point2D(1, 1), Point2D(3, 1), Point2D(15, 4)) + >>> convex_hull(*points, **dict(polygon=False)) + ([Point2D(-5, 2), Point2D(15, 4)], + [Point2D(-5, 2), Point2D(1, 1), Point2D(3, 1), Point2D(15, 4)]) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Graham_scan + + .. [2] Andrew's Monotone Chain Algorithm + (A.M. Andrew, + "Another Efficient Algorithm for Convex Hulls in Two Dimensions", 1979) + https://web.archive.org/web/20210511015444/http://geomalgorithms.com/a10-_hull-1.html + + """ + from .line import Segment + from .polygon import Polygon + p = OrderedSet() + for e in args: + if not isinstance(e, GeometryEntity): + try: + e = Point(e) + except NotImplementedError: + raise ValueError('%s is not a GeometryEntity and cannot be made into Point' % str(e)) + if isinstance(e, Point): + p.add(e) + elif isinstance(e, Segment): + p.update(e.points) + elif isinstance(e, Polygon): + p.update(e.vertices) + else: + raise NotImplementedError( + 'Convex hull for %s not implemented.' % type(e)) + + # make sure all our points are of the same dimension + if any(len(x) != 2 for x in p): + raise ValueError('Can only compute the convex hull in two dimensions') + + p = list(p) + if len(p) == 1: + return p[0] if polygon else (p[0], None) + elif len(p) == 2: + s = Segment(p[0], p[1]) + return s if polygon else (s, None) + + def _orientation(p, q, r): + '''Return positive if p-q-r are clockwise, neg if ccw, zero if + collinear.''' + return (q.y - p.y)*(r.x - p.x) - (q.x - p.x)*(r.y - p.y) + + # scan to find upper and lower convex hulls of a set of 2d points. + U = [] + L = [] + try: + p.sort(key=lambda x: x.args) + except TypeError: + raise ValueError("The points could not be sorted.") + for p_i in p: + while len(U) > 1 and _orientation(U[-2], U[-1], p_i) <= 0: + U.pop() + while len(L) > 1 and _orientation(L[-2], L[-1], p_i) >= 0: + L.pop() + U.append(p_i) + L.append(p_i) + U.reverse() + convexHull = tuple(L + U[1:-1]) + + if len(convexHull) == 2: + s = Segment(convexHull[0], convexHull[1]) + return s if polygon else (s, None) + if polygon: + return Polygon(*convexHull) + else: + U.reverse() + return (U, L) + +def farthest_points(*args): + """Return the subset of points from a set of points that were + the furthest apart from each other in the 2D plane. + + Parameters + ========== + + args + A collection of Points on 2D plane. + + Notes + ===== + + This can only be performed on a set of points whose coordinates can + be ordered on the number line. If there are no ties then a single + pair of Points will be in the set. + + Examples + ======== + + >>> from sympy.geometry import farthest_points, Triangle + >>> Triangle(sss=(3, 4, 5)).args + (Point2D(0, 0), Point2D(3, 0), Point2D(3, 4)) + >>> farthest_points(*_) + {(Point2D(0, 0), Point2D(3, 4))} + + References + ========== + + .. [1] https://code.activestate.com/recipes/117225-convex-hull-and-diameter-of-2d-point-sets/ + + .. [2] Rotating Callipers Technique + https://en.wikipedia.org/wiki/Rotating_calipers + + """ + + def rotatingCalipers(Points): + U, L = convex_hull(*Points, **{"polygon": False}) + + if L is None: + if isinstance(U, Point): + raise ValueError('At least two distinct points must be given.') + yield U.args + else: + i = 0 + j = len(L) - 1 + while i < len(U) - 1 or j > 0: + yield U[i], L[j] + # if all the way through one side of hull, advance the other side + if i == len(U) - 1: + j -= 1 + elif j == 0: + i += 1 + # still points left on both lists, compare slopes of next hull edges + # being careful to avoid divide-by-zero in slope calculation + elif (U[i+1].y - U[i].y) * (L[j].x - L[j-1].x) > \ + (L[j].y - L[j-1].y) * (U[i+1].x - U[i].x): + i += 1 + else: + j -= 1 + + p = [Point2D(i) for i in set(args)] + + if not all(i.is_Rational for j in p for i in j.args): + def hypot(x, y): + arg = x*x + y*y + if arg.is_Rational: + return _sqrt(arg) + return sqrt(arg) + else: + from math import hypot + + rv = [] + diam = 0 + for pair in rotatingCalipers(args): + h, q = _ordered_points(pair) + d = hypot(h.x - q.x, h.y - q.y) + if d > diam: + rv = [(h, q)] + elif d == diam: + rv.append((h, q)) + else: + continue + diam = d + + return set(rv) + + +def idiff(eq, y, x, n=1): + """Return ``dy/dx`` assuming that ``eq == 0``. + + Parameters + ========== + + y : the dependent variable or a list of dependent variables (with y first) + x : the variable that the derivative is being taken with respect to + n : the order of the derivative (default is 1) + + Examples + ======== + + >>> from sympy.abc import x, y, a + >>> from sympy.geometry.util import idiff + + >>> circ = x**2 + y**2 - 4 + >>> idiff(circ, y, x) + -x/y + >>> idiff(circ, y, x, 2).simplify() + (-x**2 - y**2)/y**3 + + Here, ``a`` is assumed to be independent of ``x``: + + >>> idiff(x + a + y, y, x) + -1 + + Now the x-dependence of ``a`` is made explicit by listing ``a`` after + ``y`` in a list. + + >>> idiff(x + a + y, [y, a], x) + -Derivative(a, x) - 1 + + See Also + ======== + + sympy.core.function.Derivative: represents unevaluated derivatives + sympy.core.function.diff: explicitly differentiates wrt symbols + + """ + if is_sequence(y): + dep = set(y) + y = y[0] + elif isinstance(y, Symbol): + dep = {y} + elif isinstance(y, Function): + pass + else: + raise ValueError("expecting x-dependent symbol(s) or function(s) but got: %s" % y) + + f = {s: Function(s.name)(x) for s in eq.free_symbols + if s != x and s in dep} + + if isinstance(y, Symbol): + dydx = Function(y.name)(x).diff(x) + else: + dydx = y.diff(x) + + eq = eq.subs(f) + derivs = {} + for i in range(n): + # equation will be linear in dydx, a*dydx + b, so dydx = -b/a + deq = eq.diff(x) + b = deq.xreplace({dydx: S.Zero}) + a = (deq - b).xreplace({dydx: S.One}) + yp = factor_terms(expand_mul(cancel((-b/a).subs(derivs)), deep=False)) + if i == n - 1: + return yp.subs([(v, k) for k, v in f.items()]) + derivs[dydx] = yp + eq = dydx - yp + dydx = dydx.diff(x) + + +def intersection(*entities, pairwise=False, **kwargs): + """The intersection of a collection of GeometryEntity instances. + + Parameters + ========== + entities : sequence of GeometryEntity + pairwise (keyword argument) : Can be either True or False + + Returns + ======= + intersection : list of GeometryEntity + + Raises + ====== + NotImplementedError + When unable to calculate intersection. + + Notes + ===== + The intersection of any geometrical entity with itself should return + a list with one item: the entity in question. + An intersection requires two or more entities. If only a single + entity is given then the function will return an empty list. + It is possible for `intersection` to miss intersections that one + knows exists because the required quantities were not fully + simplified internally. + Reals should be converted to Rationals, e.g. Rational(str(real_num)) + or else failures due to floating point issues may result. + + Case 1: When the keyword argument 'pairwise' is False (default value): + In this case, the function returns a list of intersections common to + all entities. + + Case 2: When the keyword argument 'pairwise' is True: + In this case, the functions returns a list intersections that occur + between any pair of entities. + + See Also + ======== + + sympy.geometry.entity.GeometryEntity.intersection + + Examples + ======== + + >>> from sympy import Ray, Circle, intersection + >>> c = Circle((0, 1), 1) + >>> intersection(c, c.center) + [] + >>> right = Ray((0, 0), (1, 0)) + >>> up = Ray((0, 0), (0, 1)) + >>> intersection(c, right, up) + [Point2D(0, 0)] + >>> intersection(c, right, up, pairwise=True) + [Point2D(0, 0), Point2D(0, 2)] + >>> left = Ray((1, 0), (0, 0)) + >>> intersection(right, left) + [Segment2D(Point2D(0, 0), Point2D(1, 0))] + + """ + if len(entities) <= 1: + return [] + + entities = list(entities) + prec = None + for i, e in enumerate(entities): + if not isinstance(e, GeometryEntity): + # entities may be an immutable tuple + e = Point(e) + # convert to exact Rationals + d = {} + for f in e.atoms(Float): + prec = f._prec if prec is None else min(f._prec, prec) + d.setdefault(f, nsimplify(f, rational=True)) + entities[i] = e.xreplace(d) + + if not pairwise: + # find the intersection common to all objects + res = entities[0].intersection(entities[1]) + for entity in entities[2:]: + newres = [] + for x in res: + newres.extend(x.intersection(entity)) + res = newres + else: + # find all pairwise intersections + ans = [] + for j in range(len(entities)): + for k in range(j + 1, len(entities)): + ans.extend(intersection(entities[j], entities[k])) + res = list(ordered(set(ans))) + + # convert back to Floats + if prec is not None: + p = prec_to_dps(prec) + res = [i.n(p) for i in res] + return res diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..45412acad0ab9e5c7424b1888648a638ef208142 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/__init__.py @@ -0,0 +1,18 @@ +r""" +The :py:mod:`~sympy.holonomic` module is intended to deal with holonomic functions along +with various operations on them like addition, multiplication, composition, +integration and differentiation. The module also implements various kinds of +conversions such as converting holonomic functions to a different form and the +other way around. +""" + +from .holonomic import (DifferentialOperator, HolonomicFunction, DifferentialOperators, + from_hyper, from_meijerg, expr_to_holonomic) +from .recurrence import RecurrenceOperators, RecurrenceOperator, HolonomicSequence + +__all__ = [ + 'DifferentialOperator', 'HolonomicFunction', 'DifferentialOperators', + 'from_hyper', 'from_meijerg', 'expr_to_holonomic', + + 'RecurrenceOperators', 'RecurrenceOperator', 'HolonomicSequence', +] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/holonomic.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/holonomic.py new file mode 100644 index 0000000000000000000000000000000000000000..e31c4d4511d4c07aa4049a62253cdb060758cf3d --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/holonomic.py @@ -0,0 +1,2765 @@ +""" +This module implements Holonomic Functions and +various operations on them. +""" + +from sympy.core import Add, Mul, Pow +from sympy.core.numbers import (NaN, Infinity, NegativeInfinity, Float, I, pi, + equal_valued, int_valued) +from sympy.core.singleton import S +from sympy.core.sorting import ordered +from sympy.core.symbol import Dummy, Symbol +from sympy.core.sympify import sympify +from sympy.functions.combinatorial.factorials import binomial, factorial, rf +from sympy.functions.elementary.exponential import exp_polar, exp, log +from sympy.functions.elementary.hyperbolic import (cosh, sinh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (cos, sin, sinc) +from sympy.functions.special.error_functions import (Ci, Shi, Si, erf, erfc, erfi) +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import hyper, meijerg +from sympy.integrals import meijerint +from sympy.matrices import Matrix +from sympy.polys.rings import PolyElement +from sympy.polys.fields import FracElement +from sympy.polys.domains import QQ, RR +from sympy.polys.polyclasses import DMF +from sympy.polys.polyroots import roots +from sympy.polys.polytools import Poly +from sympy.polys.matrices import DomainMatrix +from sympy.printing import sstr +from sympy.series.limits import limit +from sympy.series.order import Order +from sympy.simplify.hyperexpand import hyperexpand +from sympy.simplify.simplify import nsimplify +from sympy.solvers.solvers import solve + +from .recurrence import HolonomicSequence, RecurrenceOperator, RecurrenceOperators +from .holonomicerrors import (NotPowerSeriesError, NotHyperSeriesError, + SingularityError, NotHolonomicError) + + +def _find_nonzero_solution(r, homosys): + ones = lambda shape: DomainMatrix.ones(shape, r.domain) + particular, nullspace = r._solve(homosys) + nullity = nullspace.shape[0] + nullpart = ones((1, nullity)) * nullspace + sol = (particular + nullpart).transpose() + return sol + + + +def DifferentialOperators(base, generator): + r""" + This function is used to create annihilators using ``Dx``. + + Explanation + =========== + + Returns an Algebra of Differential Operators also called Weyl Algebra + and the operator for differentiation i.e. the ``Dx`` operator. + + Parameters + ========== + + base: + Base polynomial ring for the algebra. + The base polynomial ring is the ring of polynomials in :math:`x` that + will appear as coefficients in the operators. + generator: + Generator of the algebra which can + be either a noncommutative ``Symbol`` or a string. e.g. "Dx" or "D". + + Examples + ======== + + >>> from sympy import ZZ + >>> from sympy.abc import x + >>> from sympy.holonomic.holonomic import DifferentialOperators + >>> R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + >>> R + Univariate Differential Operator Algebra in intermediate Dx over the base ring ZZ[x] + >>> Dx*x + (1) + (x)*Dx + """ + + ring = DifferentialOperatorAlgebra(base, generator) + return (ring, ring.derivative_operator) + + +class DifferentialOperatorAlgebra: + r""" + An Ore Algebra is a set of noncommutative polynomials in the + intermediate ``Dx`` and coefficients in a base polynomial ring :math:`A`. + It follows the commutation rule: + + .. math :: + Dxa = \sigma(a)Dx + \delta(a) + + for :math:`a \subset A`. + + Where :math:`\sigma: A \Rightarrow A` is an endomorphism and :math:`\delta: A \rightarrow A` + is a skew-derivation i.e. :math:`\delta(ab) = \delta(a) b + \sigma(a) \delta(b)`. + + If one takes the sigma as identity map and delta as the standard derivation + then it becomes the algebra of Differential Operators also called + a Weyl Algebra i.e. an algebra whose elements are Differential Operators. + + This class represents a Weyl Algebra and serves as the parent ring for + Differential Operators. + + Examples + ======== + + >>> from sympy import ZZ + >>> from sympy import symbols + >>> from sympy.holonomic.holonomic import DifferentialOperators + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + >>> R + Univariate Differential Operator Algebra in intermediate Dx over the base ring + ZZ[x] + + See Also + ======== + + DifferentialOperator + """ + + def __init__(self, base, generator): + # the base polynomial ring for the algebra + self.base = base + # the operator representing differentiation i.e. `Dx` + self.derivative_operator = DifferentialOperator( + [base.zero, base.one], self) + + if generator is None: + self.gen_symbol = Symbol('Dx', commutative=False) + else: + if isinstance(generator, str): + self.gen_symbol = Symbol(generator, commutative=False) + elif isinstance(generator, Symbol): + self.gen_symbol = generator + + def __str__(self): + string = 'Univariate Differential Operator Algebra in intermediate '\ + + sstr(self.gen_symbol) + ' over the base ring ' + \ + (self.base).__str__() + + return string + + __repr__ = __str__ + + def __eq__(self, other): + return self.base == other.base and \ + self.gen_symbol == other.gen_symbol + + +class DifferentialOperator: + """ + Differential Operators are elements of Weyl Algebra. The Operators + are defined by a list of polynomials in the base ring and the + parent ring of the Operator i.e. the algebra it belongs to. + + Explanation + =========== + + Takes a list of polynomials for each power of ``Dx`` and the + parent ring which must be an instance of DifferentialOperatorAlgebra. + + A Differential Operator can be created easily using + the operator ``Dx``. See examples below. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import DifferentialOperator, DifferentialOperators + >>> from sympy import ZZ + >>> from sympy import symbols + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(ZZ.old_poly_ring(x),'Dx') + + >>> DifferentialOperator([0, 1, x**2], R) + (1)*Dx + (x**2)*Dx**2 + + >>> (x*Dx*x + 1 - Dx**2)**2 + (2*x**2 + 2*x + 1) + (4*x**3 + 2*x**2 - 4)*Dx + (x**4 - 6*x - 2)*Dx**2 + (-2*x**2)*Dx**3 + (1)*Dx**4 + + See Also + ======== + + DifferentialOperatorAlgebra + """ + + _op_priority = 20 + + def __init__(self, list_of_poly, parent): + """ + Parameters + ========== + + list_of_poly: + List of polynomials belonging to the base ring of the algebra. + parent: + Parent algebra of the operator. + """ + + # the parent ring for this operator + # must be an DifferentialOperatorAlgebra object + self.parent = parent + base = self.parent.base + self.x = base.gens[0] if isinstance(base.gens[0], Symbol) else base.gens[0][0] + # sequence of polynomials in x for each power of Dx + # the list should not have trailing zeroes + # represents the operator + # convert the expressions into ring elements using from_sympy + for i, j in enumerate(list_of_poly): + if not isinstance(j, base.dtype): + list_of_poly[i] = base.from_sympy(sympify(j)) + else: + list_of_poly[i] = base.from_sympy(base.to_sympy(j)) + + self.listofpoly = list_of_poly + # highest power of `Dx` + self.order = len(self.listofpoly) - 1 + + def __mul__(self, other): + """ + Multiplies two DifferentialOperator and returns another + DifferentialOperator instance using the commutation rule + Dx*a = a*Dx + a' + """ + + listofself = self.listofpoly + if isinstance(other, DifferentialOperator): + listofother = other.listofpoly + elif isinstance(other, self.parent.base.dtype): + listofother = [other] + else: + listofother = [self.parent.base.from_sympy(sympify(other))] + + # multiplies a polynomial `b` with a list of polynomials + def _mul_dmp_diffop(b, listofother): + if isinstance(listofother, list): + return [i * b for i in listofother] + return [b * listofother] + + sol = _mul_dmp_diffop(listofself[0], listofother) + + # compute Dx^i * b + def _mul_Dxi_b(b): + sol1 = [self.parent.base.zero] + sol2 = [] + + if isinstance(b, list): + for i in b: + sol1.append(i) + sol2.append(i.diff()) + else: + sol1.append(self.parent.base.from_sympy(b)) + sol2.append(self.parent.base.from_sympy(b).diff()) + + return _add_lists(sol1, sol2) + + for i in range(1, len(listofself)): + # find Dx^i * b in ith iteration + listofother = _mul_Dxi_b(listofother) + # solution = solution + listofself[i] * (Dx^i * b) + sol = _add_lists(sol, _mul_dmp_diffop(listofself[i], listofother)) + + return DifferentialOperator(sol, self.parent) + + def __rmul__(self, other): + if not isinstance(other, DifferentialOperator): + + if not isinstance(other, self.parent.base.dtype): + other = (self.parent.base).from_sympy(sympify(other)) + + sol = [other * j for j in self.listofpoly] + return DifferentialOperator(sol, self.parent) + + def __add__(self, other): + if isinstance(other, DifferentialOperator): + + sol = _add_lists(self.listofpoly, other.listofpoly) + return DifferentialOperator(sol, self.parent) + + list_self = self.listofpoly + if not isinstance(other, self.parent.base.dtype): + list_other = [((self.parent).base).from_sympy(sympify(other))] + else: + list_other = [other] + sol = [list_self[0] + list_other[0]] + list_self[1:] + return DifferentialOperator(sol, self.parent) + + __radd__ = __add__ + + def __sub__(self, other): + return self + (-1) * other + + def __rsub__(self, other): + return (-1) * self + other + + def __neg__(self): + return -1 * self + + def __truediv__(self, other): + return self * (S.One / other) + + def __pow__(self, n): + if n == 1: + return self + result = DifferentialOperator([self.parent.base.one], self.parent) + if n == 0: + return result + # if self is `Dx` + if self.listofpoly == self.parent.derivative_operator.listofpoly: + sol = [self.parent.base.zero]*n + [self.parent.base.one] + return DifferentialOperator(sol, self.parent) + x = self + while True: + if n % 2: + result *= x + n >>= 1 + if not n: + break + x *= x + return result + + def __str__(self): + listofpoly = self.listofpoly + print_str = '' + + for i, j in enumerate(listofpoly): + if j == self.parent.base.zero: + continue + + j = self.parent.base.to_sympy(j) + + if i == 0: + print_str += '(' + sstr(j) + ')' + continue + + if print_str: + print_str += ' + ' + + if i == 1: + print_str += '(' + sstr(j) + ')*%s' %(self.parent.gen_symbol) + continue + + print_str += '(' + sstr(j) + ')' + '*%s**' %(self.parent.gen_symbol) + sstr(i) + + return print_str + + __repr__ = __str__ + + def __eq__(self, other): + if isinstance(other, DifferentialOperator): + return self.listofpoly == other.listofpoly and \ + self.parent == other.parent + return self.listofpoly[0] == other and \ + all(i is self.parent.base.zero for i in self.listofpoly[1:]) + + def is_singular(self, x0): + """ + Checks if the differential equation is singular at x0. + """ + + base = self.parent.base + return x0 in roots(base.to_sympy(self.listofpoly[-1]), self.x) + + +class HolonomicFunction: + r""" + A Holonomic Function is a solution to a linear homogeneous ordinary + differential equation with polynomial coefficients. This differential + equation can also be represented by an annihilator i.e. a Differential + Operator ``L`` such that :math:`L.f = 0`. For uniqueness of these functions, + initial conditions can also be provided along with the annihilator. + + Explanation + =========== + + Holonomic functions have closure properties and thus forms a ring. + Given two Holonomic Functions f and g, their sum, product, + integral and derivative is also a Holonomic Function. + + For ordinary points initial condition should be a vector of values of + the derivatives i.e. :math:`[y(x_0), y'(x_0), y''(x_0) ... ]`. + + For regular singular points initial conditions can also be provided in this + format: + :math:`{s0: [C_0, C_1, ...], s1: [C^1_0, C^1_1, ...], ...}` + where s0, s1, ... are the roots of indicial equation and vectors + :math:`[C_0, C_1, ...], [C^0_0, C^0_1, ...], ...` are the corresponding initial + terms of the associated power series. See Examples below. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import HolonomicFunction, DifferentialOperators + >>> from sympy import QQ + >>> from sympy import symbols, S + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(QQ.old_poly_ring(x),'Dx') + + >>> p = HolonomicFunction(Dx - 1, x, 0, [1]) # e^x + >>> q = HolonomicFunction(Dx**2 + 1, x, 0, [0, 1]) # sin(x) + + >>> p + q # annihilator of e^x + sin(x) + HolonomicFunction((-1) + (1)*Dx + (-1)*Dx**2 + (1)*Dx**3, x, 0, [1, 2, 1]) + + >>> p * q # annihilator of e^x * sin(x) + HolonomicFunction((2) + (-2)*Dx + (1)*Dx**2, x, 0, [0, 1]) + + An example of initial conditions for regular singular points, + the indicial equation has only one root `1/2`. + + >>> HolonomicFunction(-S(1)/2 + x*Dx, x, 0, {S(1)/2: [1]}) + HolonomicFunction((-1/2) + (x)*Dx, x, 0, {1/2: [1]}) + + >>> HolonomicFunction(-S(1)/2 + x*Dx, x, 0, {S(1)/2: [1]}).to_expr() + sqrt(x) + + To plot a Holonomic Function, one can use `.evalf()` for numerical + computation. Here's an example on `sin(x)**2/x` using numpy and matplotlib. + + >>> import sympy.holonomic # doctest: +SKIP + >>> from sympy import var, sin # doctest: +SKIP + >>> import matplotlib.pyplot as plt # doctest: +SKIP + >>> import numpy as np # doctest: +SKIP + >>> var("x") # doctest: +SKIP + >>> r = np.linspace(1, 5, 100) # doctest: +SKIP + >>> y = sympy.holonomic.expr_to_holonomic(sin(x)**2/x, x0=1).evalf(r) # doctest: +SKIP + >>> plt.plot(r, y, label="holonomic function") # doctest: +SKIP + >>> plt.show() # doctest: +SKIP + + """ + + _op_priority = 20 + + def __init__(self, annihilator, x, x0=0, y0=None): + """ + + Parameters + ========== + + annihilator: + Annihilator of the Holonomic Function, represented by a + `DifferentialOperator` object. + x: + Variable of the function. + x0: + The point at which initial conditions are stored. + Generally an integer. + y0: + The initial condition. The proper format for the initial condition + is described in class docstring. To make the function unique, + length of the vector `y0` should be equal to or greater than the + order of differential equation. + """ + + # initial condition + self.y0 = y0 + # the point for initial conditions, default is zero. + self.x0 = x0 + # differential operator L such that L.f = 0 + self.annihilator = annihilator + self.x = x + + def __str__(self): + if self._have_init_cond(): + str_sol = 'HolonomicFunction(%s, %s, %s, %s)' % (str(self.annihilator),\ + sstr(self.x), sstr(self.x0), sstr(self.y0)) + else: + str_sol = 'HolonomicFunction(%s, %s)' % (str(self.annihilator),\ + sstr(self.x)) + + return str_sol + + __repr__ = __str__ + + def unify(self, other): + """ + Unifies the base polynomial ring of a given two Holonomic + Functions. + """ + + R1 = self.annihilator.parent.base + R2 = other.annihilator.parent.base + + dom1 = R1.dom + dom2 = R2.dom + + if R1 == R2: + return (self, other) + + R = (dom1.unify(dom2)).old_poly_ring(self.x) + + newparent, _ = DifferentialOperators(R, str(self.annihilator.parent.gen_symbol)) + + sol1 = [R1.to_sympy(i) for i in self.annihilator.listofpoly] + sol2 = [R2.to_sympy(i) for i in other.annihilator.listofpoly] + + sol1 = DifferentialOperator(sol1, newparent) + sol2 = DifferentialOperator(sol2, newparent) + + sol1 = HolonomicFunction(sol1, self.x, self.x0, self.y0) + sol2 = HolonomicFunction(sol2, other.x, other.x0, other.y0) + + return (sol1, sol2) + + def is_singularics(self): + """ + Returns True if the function have singular initial condition + in the dictionary format. + + Returns False if the function have ordinary initial condition + in the list format. + + Returns None for all other cases. + """ + + if isinstance(self.y0, dict): + return True + elif isinstance(self.y0, list): + return False + + def _have_init_cond(self): + """ + Checks if the function have initial condition. + """ + return bool(self.y0) + + def _singularics_to_ord(self): + """ + Converts a singular initial condition to ordinary if possible. + """ + a = list(self.y0)[0] + b = self.y0[a] + + if len(self.y0) == 1 and a == int(a) and a > 0: + a = int(a) + y0 = [S.Zero] * a + y0 += [j * factorial(a + i) for i, j in enumerate(b)] + + return HolonomicFunction(self.annihilator, self.x, self.x0, y0) + + def __add__(self, other): + # if the ground domains are different + if self.annihilator.parent.base != other.annihilator.parent.base: + a, b = self.unify(other) + return a + b + + deg1 = self.annihilator.order + deg2 = other.annihilator.order + dim = max(deg1, deg2) + R = self.annihilator.parent.base + K = R.get_field() + + rowsself = [self.annihilator] + rowsother = [other.annihilator] + gen = self.annihilator.parent.derivative_operator + + # constructing annihilators up to order dim + for i in range(dim - deg1): + diff1 = (gen * rowsself[-1]) + rowsself.append(diff1) + + for i in range(dim - deg2): + diff2 = (gen * rowsother[-1]) + rowsother.append(diff2) + + row = rowsself + rowsother + + # constructing the matrix of the ansatz + r = [] + + for expr in row: + p = [] + for i in range(dim + 1): + if i >= len(expr.listofpoly): + p.append(K.zero) + else: + p.append(K.new(expr.listofpoly[i].to_list())) + r.append(p) + + # solving the linear system using gauss jordan solver + r = DomainMatrix(r, (len(row), dim+1), K).transpose() + homosys = DomainMatrix.zeros((dim+1, 1), K) + sol = _find_nonzero_solution(r, homosys) + + # if a solution is not obtained then increasing the order by 1 in each + # iteration + while sol.is_zero_matrix: + dim += 1 + + diff1 = (gen * rowsself[-1]) + rowsself.append(diff1) + + diff2 = (gen * rowsother[-1]) + rowsother.append(diff2) + + row = rowsself + rowsother + r = [] + + for expr in row: + p = [] + for i in range(dim + 1): + if i >= len(expr.listofpoly): + p.append(K.zero) + else: + p.append(K.new(expr.listofpoly[i].to_list())) + r.append(p) + + # solving the linear system using gauss jordan solver + r = DomainMatrix(r, (len(row), dim+1), K).transpose() + homosys = DomainMatrix.zeros((dim+1, 1), K) + sol = _find_nonzero_solution(r, homosys) + + # taking only the coefficients needed to multiply with `self` + # can be also be done the other way by taking R.H.S and multiplying with + # `other` + sol = sol.flat()[:dim + 1 - deg1] + sol1 = _normalize(sol, self.annihilator.parent) + # annihilator of the solution + sol = sol1 * (self.annihilator) + sol = _normalize(sol.listofpoly, self.annihilator.parent, negative=False) + + if not (self._have_init_cond() and other._have_init_cond()): + return HolonomicFunction(sol, self.x) + + # both the functions have ordinary initial conditions + if self.is_singularics() == False and other.is_singularics() == False: + + # directly add the corresponding value + if self.x0 == other.x0: + # try to extended the initial conditions + # using the annihilator + y1 = _extend_y0(self, sol.order) + y2 = _extend_y0(other, sol.order) + y0 = [a + b for a, b in zip(y1, y2)] + return HolonomicFunction(sol, self.x, self.x0, y0) + + # change the initial conditions to a same point + selfat0 = self.annihilator.is_singular(0) + otherat0 = other.annihilator.is_singular(0) + if self.x0 == 0 and not selfat0 and not otherat0: + return self + other.change_ics(0) + if other.x0 == 0 and not selfat0 and not otherat0: + return self.change_ics(0) + other + + selfatx0 = self.annihilator.is_singular(self.x0) + otheratx0 = other.annihilator.is_singular(self.x0) + if not selfatx0 and not otheratx0: + return self + other.change_ics(self.x0) + return self.change_ics(other.x0) + other + + if self.x0 != other.x0: + return HolonomicFunction(sol, self.x) + + # if the functions have singular_ics + y1 = None + y2 = None + + if self.is_singularics() == False and other.is_singularics() == True: + # convert the ordinary initial condition to singular. + _y0 = [j / factorial(i) for i, j in enumerate(self.y0)] + y1 = {S.Zero: _y0} + y2 = other.y0 + elif self.is_singularics() == True and other.is_singularics() == False: + _y0 = [j / factorial(i) for i, j in enumerate(other.y0)] + y1 = self.y0 + y2 = {S.Zero: _y0} + elif self.is_singularics() == True and other.is_singularics() == True: + y1 = self.y0 + y2 = other.y0 + + # computing singular initial condition for the result + # taking union of the series terms of both functions + y0 = {} + for i in y1: + # add corresponding initial terms if the power + # on `x` is same + if i in y2: + y0[i] = [a + b for a, b in zip(y1[i], y2[i])] + else: + y0[i] = y1[i] + for i in y2: + if i not in y1: + y0[i] = y2[i] + return HolonomicFunction(sol, self.x, self.x0, y0) + + def integrate(self, limits, initcond=False): + """ + Integrates the given holonomic function. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import HolonomicFunction, DifferentialOperators + >>> from sympy import QQ + >>> from sympy import symbols + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(QQ.old_poly_ring(x),'Dx') + >>> HolonomicFunction(Dx - 1, x, 0, [1]).integrate((x, 0, x)) # e^x - 1 + HolonomicFunction((-1)*Dx + (1)*Dx**2, x, 0, [0, 1]) + >>> HolonomicFunction(Dx**2 + 1, x, 0, [1, 0]).integrate((x, 0, x)) + HolonomicFunction((1)*Dx + (1)*Dx**3, x, 0, [0, 1, 0]) + """ + + # to get the annihilator, just multiply by Dx from right + D = self.annihilator.parent.derivative_operator + + # if the function have initial conditions of the series format + if self.is_singularics() == True: + + r = self._singularics_to_ord() + if r: + return r.integrate(limits, initcond=initcond) + + # computing singular initial condition for the function + # produced after integration. + y0 = {} + for i in self.y0: + c = self.y0[i] + c2 = [] + for j, cj in enumerate(c): + if cj == 0: + c2.append(S.Zero) + + # if power on `x` is -1, the integration becomes log(x) + # TODO: Implement this case + elif i + j + 1 == 0: + raise NotImplementedError("logarithmic terms in the series are not supported") + else: + c2.append(cj / S(i + j + 1)) + y0[i + 1] = c2 + + if hasattr(limits, "__iter__"): + raise NotImplementedError("Definite integration for singular initial conditions") + + return HolonomicFunction(self.annihilator * D, self.x, self.x0, y0) + + # if no initial conditions are available for the function + if not self._have_init_cond(): + if initcond: + return HolonomicFunction(self.annihilator * D, self.x, self.x0, [S.Zero]) + return HolonomicFunction(self.annihilator * D, self.x) + + # definite integral + # initial conditions for the answer will be stored at point `a`, + # where `a` is the lower limit of the integrand + if hasattr(limits, "__iter__"): + + if len(limits) == 3 and limits[0] == self.x: + x0 = self.x0 + a = limits[1] + b = limits[2] + definite = True + + else: + definite = False + + y0 = [S.Zero] + y0 += self.y0 + + indefinite_integral = HolonomicFunction(self.annihilator * D, self.x, self.x0, y0) + + if not definite: + return indefinite_integral + + # use evalf to get the values at `a` + if x0 != a: + try: + indefinite_expr = indefinite_integral.to_expr() + except (NotHyperSeriesError, NotPowerSeriesError): + indefinite_expr = None + + if indefinite_expr: + lower = indefinite_expr.subs(self.x, a) + if isinstance(lower, NaN): + lower = indefinite_expr.limit(self.x, a) + else: + lower = indefinite_integral.evalf(a) + + if b == self.x: + y0[0] = y0[0] - lower + return HolonomicFunction(self.annihilator * D, self.x, x0, y0) + + elif S(b).is_Number: + if indefinite_expr: + upper = indefinite_expr.subs(self.x, b) + if isinstance(upper, NaN): + upper = indefinite_expr.limit(self.x, b) + else: + upper = indefinite_integral.evalf(b) + + return upper - lower + + + # if the upper limit is `x`, the answer will be a function + if b == self.x: + return HolonomicFunction(self.annihilator * D, self.x, a, y0) + + # if the upper limits is a Number, a numerical value will be returned + elif S(b).is_Number: + try: + s = HolonomicFunction(self.annihilator * D, self.x, a,\ + y0).to_expr() + indefinite = s.subs(self.x, b) + if not isinstance(indefinite, NaN): + return indefinite + else: + return s.limit(self.x, b) + except (NotHyperSeriesError, NotPowerSeriesError): + return HolonomicFunction(self.annihilator * D, self.x, a, y0).evalf(b) + + return HolonomicFunction(self.annihilator * D, self.x) + + def diff(self, *args, **kwargs): + r""" + Differentiation of the given Holonomic function. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import HolonomicFunction, DifferentialOperators + >>> from sympy import ZZ + >>> from sympy import symbols + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(ZZ.old_poly_ring(x),'Dx') + >>> HolonomicFunction(Dx**2 + 1, x, 0, [0, 1]).diff().to_expr() + cos(x) + >>> HolonomicFunction(Dx - 2, x, 0, [1]).diff().to_expr() + 2*exp(2*x) + + See Also + ======== + + integrate + """ + kwargs.setdefault('evaluate', True) + if args: + if args[0] != self.x: + return S.Zero + elif len(args) == 2: + sol = self + for i in range(args[1]): + sol = sol.diff(args[0]) + return sol + + ann = self.annihilator + + # if the function is constant. + if ann.listofpoly[0] == ann.parent.base.zero and ann.order == 1: + return S.Zero + + # if the coefficient of y in the differential equation is zero. + # a shifting is done to compute the answer in this case. + elif ann.listofpoly[0] == ann.parent.base.zero: + + sol = DifferentialOperator(ann.listofpoly[1:], ann.parent) + + if self._have_init_cond(): + # if ordinary initial condition + if self.is_singularics() == False: + return HolonomicFunction(sol, self.x, self.x0, self.y0[1:]) + # TODO: support for singular initial condition + return HolonomicFunction(sol, self.x) + else: + return HolonomicFunction(sol, self.x) + + # the general algorithm + R = ann.parent.base + K = R.get_field() + + seq_dmf = [K.new(i.to_list()) for i in ann.listofpoly] + + # -y = a1*y'/a0 + a2*y''/a0 ... + an*y^n/a0 + rhs = [i / seq_dmf[0] for i in seq_dmf[1:]] + rhs.insert(0, K.zero) + + # differentiate both lhs and rhs + sol = _derivate_diff_eq(rhs, K) + + # add the term y' in lhs to rhs + sol = _add_lists(sol, [K.zero, K.one]) + + sol = _normalize(sol[1:], self.annihilator.parent, negative=False) + + if not self._have_init_cond() or self.is_singularics() == True: + return HolonomicFunction(sol, self.x) + + y0 = _extend_y0(self, sol.order + 1)[1:] + return HolonomicFunction(sol, self.x, self.x0, y0) + + def __eq__(self, other): + if self.annihilator != other.annihilator or self.x != other.x: + return False + if self._have_init_cond() and other._have_init_cond(): + return self.x0 == other.x0 and self.y0 == other.y0 + return True + + def __mul__(self, other): + ann_self = self.annihilator + + if not isinstance(other, HolonomicFunction): + other = sympify(other) + + if other.has(self.x): + raise NotImplementedError(" Can't multiply a HolonomicFunction and expressions/functions.") + + if not self._have_init_cond(): + return self + y0 = _extend_y0(self, ann_self.order) + y1 = [(Poly.new(j, self.x) * other).rep for j in y0] + return HolonomicFunction(ann_self, self.x, self.x0, y1) + + if self.annihilator.parent.base != other.annihilator.parent.base: + a, b = self.unify(other) + return a * b + + ann_other = other.annihilator + + a = ann_self.order + b = ann_other.order + + R = ann_self.parent.base + K = R.get_field() + + list_self = [K.new(j.to_list()) for j in ann_self.listofpoly] + list_other = [K.new(j.to_list()) for j in ann_other.listofpoly] + + # will be used to reduce the degree + self_red = [-list_self[i] / list_self[a] for i in range(a)] + + other_red = [-list_other[i] / list_other[b] for i in range(b)] + + # coeff_mull[i][j] is the coefficient of Dx^i(f).Dx^j(g) + coeff_mul = [[K.zero for i in range(b + 1)] for j in range(a + 1)] + coeff_mul[0][0] = K.one + + # making the ansatz + lin_sys_elements = [[coeff_mul[i][j] for i in range(a) for j in range(b)]] + lin_sys = DomainMatrix(lin_sys_elements, (1, a*b), K).transpose() + + homo_sys = DomainMatrix.zeros((a*b, 1), K) + + sol = _find_nonzero_solution(lin_sys, homo_sys) + + # until a non trivial solution is found + while sol.is_zero_matrix: + + # updating the coefficients Dx^i(f).Dx^j(g) for next degree + for i in range(a - 1, -1, -1): + for j in range(b - 1, -1, -1): + coeff_mul[i][j + 1] += coeff_mul[i][j] + coeff_mul[i + 1][j] += coeff_mul[i][j] + if isinstance(coeff_mul[i][j], K.dtype): + coeff_mul[i][j] = DMFdiff(coeff_mul[i][j], K) + else: + coeff_mul[i][j] = coeff_mul[i][j].diff(self.x) + + # reduce the terms to lower power using annihilators of f, g + for i in range(a + 1): + if coeff_mul[i][b].is_zero: + continue + for j in range(b): + coeff_mul[i][j] += other_red[j] * coeff_mul[i][b] + coeff_mul[i][b] = K.zero + + # not d2 + 1, as that is already covered in previous loop + for j in range(b): + if coeff_mul[a][j] == 0: + continue + for i in range(a): + coeff_mul[i][j] += self_red[i] * coeff_mul[a][j] + coeff_mul[a][j] = K.zero + + lin_sys_elements.append([coeff_mul[i][j] for i in range(a) for j in range(b)]) + lin_sys = DomainMatrix(lin_sys_elements, (len(lin_sys_elements), a*b), K).transpose() + + sol = _find_nonzero_solution(lin_sys, homo_sys) + + sol_ann = _normalize(sol.flat(), self.annihilator.parent, negative=False) + + if not (self._have_init_cond() and other._have_init_cond()): + return HolonomicFunction(sol_ann, self.x) + + if self.is_singularics() == False and other.is_singularics() == False: + + # if both the conditions are at same point + if self.x0 == other.x0: + + # try to find more initial conditions + y0_self = _extend_y0(self, sol_ann.order) + y0_other = _extend_y0(other, sol_ann.order) + # h(x0) = f(x0) * g(x0) + y0 = [y0_self[0] * y0_other[0]] + + # coefficient of Dx^j(f)*Dx^i(g) in Dx^i(fg) + for i in range(1, min(len(y0_self), len(y0_other))): + coeff = [[0 for i in range(i + 1)] for j in range(i + 1)] + for j in range(i + 1): + for k in range(i + 1): + if j + k == i: + coeff[j][k] = binomial(i, j) + + sol = 0 + for j in range(i + 1): + for k in range(i + 1): + sol += coeff[j][k]* y0_self[j] * y0_other[k] + + y0.append(sol) + + return HolonomicFunction(sol_ann, self.x, self.x0, y0) + + # if the points are different, consider one + selfat0 = self.annihilator.is_singular(0) + otherat0 = other.annihilator.is_singular(0) + + if self.x0 == 0 and not selfat0 and not otherat0: + return self * other.change_ics(0) + if other.x0 == 0 and not selfat0 and not otherat0: + return self.change_ics(0) * other + + selfatx0 = self.annihilator.is_singular(self.x0) + otheratx0 = other.annihilator.is_singular(self.x0) + if not selfatx0 and not otheratx0: + return self * other.change_ics(self.x0) + return self.change_ics(other.x0) * other + + if self.x0 != other.x0: + return HolonomicFunction(sol_ann, self.x) + + # if the functions have singular_ics + y1 = None + y2 = None + + if self.is_singularics() == False and other.is_singularics() == True: + _y0 = [j / factorial(i) for i, j in enumerate(self.y0)] + y1 = {S.Zero: _y0} + y2 = other.y0 + elif self.is_singularics() == True and other.is_singularics() == False: + _y0 = [j / factorial(i) for i, j in enumerate(other.y0)] + y1 = self.y0 + y2 = {S.Zero: _y0} + elif self.is_singularics() == True and other.is_singularics() == True: + y1 = self.y0 + y2 = other.y0 + + y0 = {} + # multiply every possible pair of the series terms + for i in y1: + for j in y2: + k = min(len(y1[i]), len(y2[j])) + c = [sum((y1[i][b] * y2[j][a - b] for b in range(a + 1)), + start=S.Zero) for a in range(k)] + if not i + j in y0: + y0[i + j] = c + else: + y0[i + j] = [a + b for a, b in zip(c, y0[i + j])] + return HolonomicFunction(sol_ann, self.x, self.x0, y0) + + __rmul__ = __mul__ + + def __sub__(self, other): + return self + other * -1 + + def __rsub__(self, other): + return self * -1 + other + + def __neg__(self): + return -1 * self + + def __truediv__(self, other): + return self * (S.One / other) + + def __pow__(self, n): + if self.annihilator.order <= 1: + ann = self.annihilator + parent = ann.parent + + if self.y0 is None: + y0 = None + else: + y0 = [list(self.y0)[0] ** n] + + p0 = ann.listofpoly[0] + p1 = ann.listofpoly[1] + + p0 = (Poly.new(p0, self.x) * n).rep + + sol = [parent.base.to_sympy(i) for i in [p0, p1]] + dd = DifferentialOperator(sol, parent) + return HolonomicFunction(dd, self.x, self.x0, y0) + if n < 0: + raise NotHolonomicError("Negative Power on a Holonomic Function") + Dx = self.annihilator.parent.derivative_operator + result = HolonomicFunction(Dx, self.x, S.Zero, [S.One]) + if n == 0: + return result + x = self + while True: + if n % 2: + result *= x + n >>= 1 + if not n: + break + x *= x + return result + + def degree(self): + """ + Returns the highest power of `x` in the annihilator. + """ + return max(i.degree() for i in self.annihilator.listofpoly) + + def composition(self, expr, *args, **kwargs): + """ + Returns function after composition of a holonomic + function with an algebraic function. The method cannot compute + initial conditions for the result by itself, so they can be also be + provided. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import HolonomicFunction, DifferentialOperators + >>> from sympy import QQ + >>> from sympy import symbols + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(QQ.old_poly_ring(x),'Dx') + >>> HolonomicFunction(Dx - 1, x).composition(x**2, 0, [1]) # e^(x**2) + HolonomicFunction((-2*x) + (1)*Dx, x, 0, [1]) + >>> HolonomicFunction(Dx**2 + 1, x).composition(x**2 - 1, 1, [1, 0]) + HolonomicFunction((4*x**3) + (-1)*Dx + (x)*Dx**2, x, 1, [1, 0]) + + See Also + ======== + + from_hyper + """ + + R = self.annihilator.parent + a = self.annihilator.order + diff = expr.diff(self.x) + listofpoly = self.annihilator.listofpoly + + for i, j in enumerate(listofpoly): + if isinstance(j, self.annihilator.parent.base.dtype): + listofpoly[i] = self.annihilator.parent.base.to_sympy(j) + + r = listofpoly[a].subs({self.x:expr}) + subs = [-listofpoly[i].subs({self.x:expr}) / r for i in range (a)] + coeffs = [S.Zero for i in range(a)] # coeffs[i] == coeff of (D^i f)(a) in D^k (f(a)) + coeffs[0] = S.One + system = [coeffs] + homogeneous = Matrix([[S.Zero for i in range(a)]]).transpose() + while True: + coeffs_next = [p.diff(self.x) for p in coeffs] + for i in range(a - 1): + coeffs_next[i + 1] += (coeffs[i] * diff) + for i in range(a): + coeffs_next[i] += (coeffs[-1] * subs[i] * diff) + coeffs = coeffs_next + # check for linear relations + system.append(coeffs) + sol, taus = (Matrix(system).transpose() + ).gauss_jordan_solve(homogeneous) + if sol.is_zero_matrix is not True: + break + + tau = list(taus)[0] + sol = sol.subs(tau, 1) + sol = _normalize(sol[0:], R, negative=False) + + # if initial conditions are given for the resulting function + if args: + return HolonomicFunction(sol, self.x, args[0], args[1]) + return HolonomicFunction(sol, self.x) + + def to_sequence(self, lb=True): + r""" + Finds recurrence relation for the coefficients in the series expansion + of the function about :math:`x_0`, where :math:`x_0` is the point at + which the initial condition is stored. + + Explanation + =========== + + If the point :math:`x_0` is ordinary, solution of the form :math:`[(R, n_0)]` + is returned. Where :math:`R` is the recurrence relation and :math:`n_0` is the + smallest ``n`` for which the recurrence holds true. + + If the point :math:`x_0` is regular singular, a list of solutions in + the format :math:`(R, p, n_0)` is returned, i.e. `[(R, p, n_0), ... ]`. + Each tuple in this vector represents a recurrence relation :math:`R` + associated with a root of the indicial equation ``p``. Conditions of + a different format can also be provided in this case, see the + docstring of HolonomicFunction class. + + If it's not possible to numerically compute a initial condition, + it is returned as a symbol :math:`C_j`, denoting the coefficient of + :math:`(x - x_0)^j` in the power series about :math:`x_0`. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import HolonomicFunction, DifferentialOperators + >>> from sympy import QQ + >>> from sympy import symbols, S + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(QQ.old_poly_ring(x),'Dx') + >>> HolonomicFunction(Dx - 1, x, 0, [1]).to_sequence() + [(HolonomicSequence((-1) + (n + 1)Sn, n), u(0) = 1, 0)] + >>> HolonomicFunction((1 + x)*Dx**2 + Dx, x, 0, [0, 1]).to_sequence() + [(HolonomicSequence((n**2) + (n**2 + n)Sn, n), u(0) = 0, u(1) = 1, u(2) = -1/2, 2)] + >>> HolonomicFunction(-S(1)/2 + x*Dx, x, 0, {S(1)/2: [1]}).to_sequence() + [(HolonomicSequence((n), n), u(0) = 1, 1/2, 1)] + + See Also + ======== + + HolonomicFunction.series + + References + ========== + + .. [1] https://hal.inria.fr/inria-00070025/document + .. [2] https://www3.risc.jku.at/publications/download/risc_2244/DIPLFORM.pdf + + """ + + if self.x0 != 0: + return self.shift_x(self.x0).to_sequence() + + # check whether a power series exists if the point is singular + if self.annihilator.is_singular(self.x0): + return self._frobenius(lb=lb) + + dict1 = {} + n = Symbol('n', integer=True) + dom = self.annihilator.parent.base.dom + R, _ = RecurrenceOperators(dom.old_poly_ring(n), 'Sn') + + # substituting each term of the form `x^k Dx^j` in the + # annihilator, according to the formula below: + # x^k Dx^j = Sum(rf(n + 1 - k, j) * a(n + j - k) * x^n, (n, k, oo)) + # for explanation see [2]. + for i, j in enumerate(self.annihilator.listofpoly): + + listofdmp = j.all_coeffs() + degree = len(listofdmp) - 1 + + for k in range(degree + 1): + coeff = listofdmp[degree - k] + + if coeff == 0: + continue + + if (i - k, k) in dict1: + dict1[(i - k, k)] += (dom.to_sympy(coeff) * rf(n - k + 1, i)) + else: + dict1[(i - k, k)] = (dom.to_sympy(coeff) * rf(n - k + 1, i)) + + + sol = [] + keylist = [i[0] for i in dict1] + lower = min(keylist) + upper = max(keylist) + degree = self.degree() + + # the recurrence relation holds for all values of + # n greater than smallest_n, i.e. n >= smallest_n + smallest_n = lower + degree + dummys = {} + eqs = [] + unknowns = [] + + # an appropriate shift of the recurrence + for j in range(lower, upper + 1): + if j in keylist: + temp = sum((v.subs(n, n - lower) + for k, v in dict1.items() if k[0] == j), + start=S.Zero) + sol.append(temp) + else: + sol.append(S.Zero) + + # the recurrence relation + sol = RecurrenceOperator(sol, R) + + # computing the initial conditions for recurrence + order = sol.order + all_roots = roots(R.base.to_sympy(sol.listofpoly[-1]), n, filter='Z') + all_roots = all_roots.keys() + + if all_roots: + max_root = max(all_roots) + 1 + smallest_n = max(max_root, smallest_n) + order += smallest_n + + y0 = _extend_y0(self, order) + # u(n) = y^n(0)/factorial(n) + u0 = [j / factorial(i) for i, j in enumerate(y0)] + + # if sufficient conditions can't be computed then + # try to use the series method i.e. + # equate the coefficients of x^k in the equation formed by + # substituting the series in differential equation, to zero. + if len(u0) < order: + + for i in range(degree): + eq = S.Zero + + for j in dict1: + + if i + j[0] < 0: + dummys[i + j[0]] = S.Zero + + elif i + j[0] < len(u0): + dummys[i + j[0]] = u0[i + j[0]] + + elif not i + j[0] in dummys: + dummys[i + j[0]] = Symbol('C_%s' %(i + j[0])) + unknowns.append(dummys[i + j[0]]) + + if j[1] <= i: + eq += dict1[j].subs(n, i) * dummys[i + j[0]] + + eqs.append(eq) + + # solve the system of equations formed + soleqs = solve(eqs, *unknowns) + + if isinstance(soleqs, dict): + + for i in range(len(u0), order): + + if i not in dummys: + dummys[i] = Symbol('C_%s' %i) + + if dummys[i] in soleqs: + u0.append(soleqs[dummys[i]]) + + else: + u0.append(dummys[i]) + + if lb: + return [(HolonomicSequence(sol, u0), smallest_n)] + return [HolonomicSequence(sol, u0)] + + for i in range(len(u0), order): + + if i not in dummys: + dummys[i] = Symbol('C_%s' %i) + + s = False + for j in soleqs: + if dummys[i] in j: + u0.append(j[dummys[i]]) + s = True + if not s: + u0.append(dummys[i]) + + if lb: + return [(HolonomicSequence(sol, u0), smallest_n)] + + return [HolonomicSequence(sol, u0)] + + def _frobenius(self, lb=True): + # compute the roots of indicial equation + indicialroots = self._indicial() + + reals = [] + compl = [] + for i in ordered(indicialroots.keys()): + if i.is_real: + reals.extend([i] * indicialroots[i]) + else: + a, b = i.as_real_imag() + compl.extend([(i, a, b)] * indicialroots[i]) + + # sort the roots for a fixed ordering of solution + compl.sort(key=lambda x : x[1]) + compl.sort(key=lambda x : x[2]) + reals.sort() + + # grouping the roots, roots differ by an integer are put in the same group. + grp = [] + + for i in reals: + if len(grp) == 0: + grp.append([i]) + continue + for j in grp: + if int_valued(j[0] - i): + j.append(i) + break + else: + grp.append([i]) + + # True if none of the roots differ by an integer i.e. + # each element in group have only one member + independent = all(len(i) == 1 for i in grp) + + allpos = all(i >= 0 for i in reals) + allint = all(int_valued(i) for i in reals) + + # if initial conditions are provided + # then use them. + if self.is_singularics() == True: + rootstoconsider = [] + for i in ordered(self.y0.keys()): + for j in ordered(indicialroots.keys()): + if equal_valued(j, i): + rootstoconsider.append(i) + + elif allpos and allint: + rootstoconsider = [min(reals)] + + elif independent: + rootstoconsider = [i[0] for i in grp] + [j[0] for j in compl] + + elif not allint: + rootstoconsider = [i for i in reals if not int(i) == i] + + elif not allpos: + + if not self._have_init_cond() or S(self.y0[0]).is_finite == False: + rootstoconsider = [min(reals)] + + else: + posroots = [i for i in reals if i >= 0] + rootstoconsider = [min(posroots)] + + n = Symbol('n', integer=True) + dom = self.annihilator.parent.base.dom + R, _ = RecurrenceOperators(dom.old_poly_ring(n), 'Sn') + + finalsol = [] + char = ord('C') + + for p in rootstoconsider: + dict1 = {} + + for i, j in enumerate(self.annihilator.listofpoly): + + listofdmp = j.all_coeffs() + degree = len(listofdmp) - 1 + + for k in range(degree + 1): + coeff = listofdmp[degree - k] + + if coeff == 0: + continue + + if (i - k, k - i) in dict1: + dict1[(i - k, k - i)] += (dom.to_sympy(coeff) * rf(n - k + 1 + p, i)) + else: + dict1[(i - k, k - i)] = (dom.to_sympy(coeff) * rf(n - k + 1 + p, i)) + + sol = [] + keylist = [i[0] for i in dict1] + lower = min(keylist) + upper = max(keylist) + degree = max(i[1] for i in dict1) + degree2 = min(i[1] for i in dict1) + + smallest_n = lower + degree + dummys = {} + eqs = [] + unknowns = [] + + for j in range(lower, upper + 1): + if j in keylist: + temp = sum((v.subs(n, n - lower) + for k, v in dict1.items() if k[0] == j), + start=S.Zero) + sol.append(temp) + else: + sol.append(S.Zero) + + # the recurrence relation + sol = RecurrenceOperator(sol, R) + + # computing the initial conditions for recurrence + order = sol.order + all_roots = roots(R.base.to_sympy(sol.listofpoly[-1]), n, filter='Z') + all_roots = all_roots.keys() + + if all_roots: + max_root = max(all_roots) + 1 + smallest_n = max(max_root, smallest_n) + order += smallest_n + + u0 = [] + + if self.is_singularics() == True: + u0 = self.y0[p] + + elif self.is_singularics() == False and p >= 0 and int(p) == p and len(rootstoconsider) == 1: + y0 = _extend_y0(self, order + int(p)) + # u(n) = y^n(0)/factorial(n) + if len(y0) > int(p): + u0 = [y0[i] / factorial(i) for i in range(int(p), len(y0))] + + if len(u0) < order: + + for i in range(degree2, degree): + eq = S.Zero + + for j in dict1: + if i + j[0] < 0: + dummys[i + j[0]] = S.Zero + + elif i + j[0] < len(u0): + dummys[i + j[0]] = u0[i + j[0]] + + elif not i + j[0] in dummys: + letter = chr(char) + '_%s' %(i + j[0]) + dummys[i + j[0]] = Symbol(letter) + unknowns.append(dummys[i + j[0]]) + + if j[1] <= i: + eq += dict1[j].subs(n, i) * dummys[i + j[0]] + + eqs.append(eq) + + # solve the system of equations formed + soleqs = solve(eqs, *unknowns) + + if isinstance(soleqs, dict): + + for i in range(len(u0), order): + + if i not in dummys: + letter = chr(char) + '_%s' %i + dummys[i] = Symbol(letter) + + if dummys[i] in soleqs: + u0.append(soleqs[dummys[i]]) + + else: + u0.append(dummys[i]) + + if lb: + finalsol.append((HolonomicSequence(sol, u0), p, smallest_n)) + continue + else: + finalsol.append((HolonomicSequence(sol, u0), p)) + continue + + for i in range(len(u0), order): + + if i not in dummys: + letter = chr(char) + '_%s' %i + dummys[i] = Symbol(letter) + + s = False + for j in soleqs: + if dummys[i] in j: + u0.append(j[dummys[i]]) + s = True + if not s: + u0.append(dummys[i]) + if lb: + finalsol.append((HolonomicSequence(sol, u0), p, smallest_n)) + + else: + finalsol.append((HolonomicSequence(sol, u0), p)) + char += 1 + return finalsol + + def series(self, n=6, coefficient=False, order=True, _recur=None): + r""" + Finds the power series expansion of given holonomic function about :math:`x_0`. + + Explanation + =========== + + A list of series might be returned if :math:`x_0` is a regular point with + multiple roots of the indicial equation. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import HolonomicFunction, DifferentialOperators + >>> from sympy import QQ + >>> from sympy import symbols + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(QQ.old_poly_ring(x),'Dx') + >>> HolonomicFunction(Dx - 1, x, 0, [1]).series() # e^x + 1 + x + x**2/2 + x**3/6 + x**4/24 + x**5/120 + O(x**6) + >>> HolonomicFunction(Dx**2 + 1, x, 0, [0, 1]).series(n=8) # sin(x) + x - x**3/6 + x**5/120 - x**7/5040 + O(x**8) + + See Also + ======== + + HolonomicFunction.to_sequence + """ + + if _recur is None: + recurrence = self.to_sequence() + else: + recurrence = _recur + + if isinstance(recurrence, tuple) and len(recurrence) == 2: + recurrence = recurrence[0] + constantpower = 0 + elif isinstance(recurrence, tuple) and len(recurrence) == 3: + constantpower = recurrence[1] + recurrence = recurrence[0] + + elif len(recurrence) == 1 and len(recurrence[0]) == 2: + recurrence = recurrence[0][0] + constantpower = 0 + elif len(recurrence) == 1 and len(recurrence[0]) == 3: + constantpower = recurrence[0][1] + recurrence = recurrence[0][0] + else: + return [self.series(_recur=i) for i in recurrence] + + n = n - int(constantpower) + l = len(recurrence.u0) - 1 + k = recurrence.recurrence.order + x = self.x + x0 = self.x0 + seq_dmp = recurrence.recurrence.listofpoly + R = recurrence.recurrence.parent.base + K = R.get_field() + seq = [K.new(j.to_list()) for j in seq_dmp] + sub = [-seq[i] / seq[k] for i in range(k)] + sol = list(recurrence.u0) + + if l + 1 < n: + # use the initial conditions to find the next term + for i in range(l + 1 - k, n - k): + coeff = sum((DMFsubs(sub[j], i) * sol[i + j] + for j in range(k) if i + j >= 0), start=S.Zero) + sol.append(coeff) + + if coefficient: + return sol + + ser = sum((x**(i + constantpower) * j for i, j in enumerate(sol)), + start=S.Zero) + if order: + ser += Order(x**(n + int(constantpower)), x) + if x0 != 0: + return ser.subs(x, x - x0) + return ser + + def _indicial(self): + """ + Computes roots of the Indicial equation. + """ + + if self.x0 != 0: + return self.shift_x(self.x0)._indicial() + + list_coeff = self.annihilator.listofpoly + R = self.annihilator.parent.base + x = self.x + s = R.zero + y = R.one + + def _pole_degree(poly): + root_all = roots(R.to_sympy(poly), x, filter='Z') + if 0 in root_all.keys(): + return root_all[0] + else: + return 0 + + degree = max(j.degree() for j in list_coeff) + inf = 10 * (max(1, degree) + max(1, self.annihilator.order)) + + deg = lambda q: inf if q.is_zero else _pole_degree(q) + b = min(deg(q) - j for j, q in enumerate(list_coeff)) + + for i, j in enumerate(list_coeff): + listofdmp = j.all_coeffs() + degree = len(listofdmp) - 1 + if 0 <= i + b <= degree: + s = s + listofdmp[degree - i - b] * y + y *= R.from_sympy(x - i) + + return roots(R.to_sympy(s), x) + + def evalf(self, points, method='RK4', h=0.05, derivatives=False): + r""" + Finds numerical value of a holonomic function using numerical methods. + (RK4 by default). A set of points (real or complex) must be provided + which will be the path for the numerical integration. + + Explanation + =========== + + The path should be given as a list :math:`[x_1, x_2, \dots x_n]`. The numerical + values will be computed at each point in this order + :math:`x_1 \rightarrow x_2 \rightarrow x_3 \dots \rightarrow x_n`. + + Returns values of the function at :math:`x_1, x_2, \dots x_n` in a list. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import HolonomicFunction, DifferentialOperators + >>> from sympy import QQ + >>> from sympy import symbols + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(QQ.old_poly_ring(x),'Dx') + + A straight line on the real axis from (0 to 1) + + >>> r = [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1] + + Runge-Kutta 4th order on e^x from 0.1 to 1. + Exact solution at 1 is 2.71828182845905 + + >>> HolonomicFunction(Dx - 1, x, 0, [1]).evalf(r) + [1.10517083333333, 1.22140257085069, 1.34985849706254, 1.49182424008069, + 1.64872063859684, 1.82211796209193, 2.01375162659678, 2.22553956329232, + 2.45960141378007, 2.71827974413517] + + Euler's method for the same + + >>> HolonomicFunction(Dx - 1, x, 0, [1]).evalf(r, method='Euler') + [1.1, 1.21, 1.331, 1.4641, 1.61051, 1.771561, 1.9487171, 2.14358881, + 2.357947691, 2.5937424601] + + One can also observe that the value obtained using Runge-Kutta 4th order + is much more accurate than Euler's method. + """ + + from sympy.holonomic.numerical import _evalf + lp = False + + # if a point `b` is given instead of a mesh + if not hasattr(points, "__iter__"): + lp = True + b = S(points) + if self.x0 == b: + return _evalf(self, [b], method=method, derivatives=derivatives)[-1] + + if not b.is_Number: + raise NotImplementedError + + a = self.x0 + if a > b: + h = -h + n = int((b - a) / h) + points = [a + h] + for i in range(n - 1): + points.append(points[-1] + h) + + for i in roots(self.annihilator.parent.base.to_sympy(self.annihilator.listofpoly[-1]), self.x): + if i == self.x0 or i in points: + raise SingularityError(self, i) + + if lp: + return _evalf(self, points, method=method, derivatives=derivatives)[-1] + return _evalf(self, points, method=method, derivatives=derivatives) + + def change_x(self, z): + """ + Changes only the variable of Holonomic Function, for internal + purposes. For composition use HolonomicFunction.composition() + """ + + dom = self.annihilator.parent.base.dom + R = dom.old_poly_ring(z) + parent, _ = DifferentialOperators(R, 'Dx') + sol = [R(j.to_list()) for j in self.annihilator.listofpoly] + sol = DifferentialOperator(sol, parent) + return HolonomicFunction(sol, z, self.x0, self.y0) + + def shift_x(self, a): + """ + Substitute `x + a` for `x`. + """ + + x = self.x + listaftershift = self.annihilator.listofpoly + base = self.annihilator.parent.base + + sol = [base.from_sympy(base.to_sympy(i).subs(x, x + a)) for i in listaftershift] + sol = DifferentialOperator(sol, self.annihilator.parent) + x0 = self.x0 - a + if not self._have_init_cond(): + return HolonomicFunction(sol, x) + return HolonomicFunction(sol, x, x0, self.y0) + + def to_hyper(self, as_list=False, _recur=None): + r""" + Returns a hypergeometric function (or linear combination of them) + representing the given holonomic function. + + Explanation + =========== + + Returns an answer of the form: + `a_1 \cdot x^{b_1} \cdot{hyper()} + a_2 \cdot x^{b_2} \cdot{hyper()} \dots` + + This is very useful as one can now use ``hyperexpand`` to find the + symbolic expressions/functions. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import HolonomicFunction, DifferentialOperators + >>> from sympy import ZZ + >>> from sympy import symbols + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(ZZ.old_poly_ring(x),'Dx') + >>> # sin(x) + >>> HolonomicFunction(Dx**2 + 1, x, 0, [0, 1]).to_hyper() + x*hyper((), (3/2,), -x**2/4) + >>> # exp(x) + >>> HolonomicFunction(Dx - 1, x, 0, [1]).to_hyper() + hyper((), (), x) + + See Also + ======== + + from_hyper, from_meijerg + """ + + if _recur is None: + recurrence = self.to_sequence() + else: + recurrence = _recur + + if isinstance(recurrence, tuple) and len(recurrence) == 2: + smallest_n = recurrence[1] + recurrence = recurrence[0] + constantpower = 0 + elif isinstance(recurrence, tuple) and len(recurrence) == 3: + smallest_n = recurrence[2] + constantpower = recurrence[1] + recurrence = recurrence[0] + elif len(recurrence) == 1 and len(recurrence[0]) == 2: + smallest_n = recurrence[0][1] + recurrence = recurrence[0][0] + constantpower = 0 + elif len(recurrence) == 1 and len(recurrence[0]) == 3: + smallest_n = recurrence[0][2] + constantpower = recurrence[0][1] + recurrence = recurrence[0][0] + else: + sol = self.to_hyper(as_list=as_list, _recur=recurrence[0]) + for i in recurrence[1:]: + sol += self.to_hyper(as_list=as_list, _recur=i) + return sol + + u0 = recurrence.u0 + r = recurrence.recurrence + x = self.x + x0 = self.x0 + + # order of the recurrence relation + m = r.order + + # when no recurrence exists, and the power series have finite terms + if m == 0: + nonzeroterms = roots(r.parent.base.to_sympy(r.listofpoly[0]), recurrence.n, filter='R') + + sol = S.Zero + for j, i in enumerate(nonzeroterms): + + if i < 0 or not int_valued(i): + continue + + i = int(i) + if i < len(u0): + if isinstance(u0[i], (PolyElement, FracElement)): + u0[i] = u0[i].as_expr() + sol += u0[i] * x**i + + else: + sol += Symbol('C_%s' %j) * x**i + + if isinstance(sol, (PolyElement, FracElement)): + sol = sol.as_expr() * x**constantpower + else: + sol = sol * x**constantpower + if as_list: + if x0 != 0: + return [(sol.subs(x, x - x0), )] + return [(sol, )] + if x0 != 0: + return sol.subs(x, x - x0) + return sol + + if smallest_n + m > len(u0): + raise NotImplementedError("Can't compute sufficient Initial Conditions") + + # check if the recurrence represents a hypergeometric series + if any(i != r.parent.base.zero for i in r.listofpoly[1:-1]): + raise NotHyperSeriesError(self, self.x0) + + a = r.listofpoly[0] + b = r.listofpoly[-1] + + # the constant multiple of argument of hypergeometric function + if isinstance(a.LC(), (PolyElement, FracElement)): + c = - (S(a.LC().as_expr()) * m**(a.degree())) / (S(b.LC().as_expr()) * m**(b.degree())) + else: + c = - (S(a.LC()) * m**(a.degree())) / (S(b.LC()) * m**(b.degree())) + + sol = 0 + + arg1 = roots(r.parent.base.to_sympy(a), recurrence.n) + arg2 = roots(r.parent.base.to_sympy(b), recurrence.n) + + # iterate through the initial conditions to find + # the hypergeometric representation of the given + # function. + # The answer will be a linear combination + # of different hypergeometric series which satisfies + # the recurrence. + if as_list: + listofsol = [] + for i in range(smallest_n + m): + + # if the recurrence relation doesn't hold for `n = i`, + # then a Hypergeometric representation doesn't exist. + # add the algebraic term a * x**i to the solution, + # where a is u0[i] + if i < smallest_n: + if as_list: + listofsol.append(((S(u0[i]) * x**(i+constantpower)).subs(x, x-x0), )) + else: + sol += S(u0[i]) * x**i + continue + + # if the coefficient u0[i] is zero, then the + # independent hypergeomtric series starting with + # x**i is not a part of the answer. + if S(u0[i]) == 0: + continue + + ap = [] + bq = [] + + # substitute m * n + i for n + for k in ordered(arg1.keys()): + ap.extend([nsimplify((i - k) / m)] * arg1[k]) + + for k in ordered(arg2.keys()): + bq.extend([nsimplify((i - k) / m)] * arg2[k]) + + # convention of (k + 1) in the denominator + if 1 in bq: + bq.remove(1) + else: + ap.append(1) + if as_list: + listofsol.append(((S(u0[i])*x**(i+constantpower)).subs(x, x-x0), (hyper(ap, bq, c*x**m)).subs(x, x-x0))) + else: + sol += S(u0[i]) * hyper(ap, bq, c * x**m) * x**i + if as_list: + return listofsol + sol = sol * x**constantpower + if x0 != 0: + return sol.subs(x, x - x0) + + return sol + + def to_expr(self): + """ + Converts a Holonomic Function back to elementary functions. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import HolonomicFunction, DifferentialOperators + >>> from sympy import ZZ + >>> from sympy import symbols, S + >>> x = symbols('x') + >>> R, Dx = DifferentialOperators(ZZ.old_poly_ring(x),'Dx') + >>> HolonomicFunction(x**2*Dx**2 + x*Dx + (x**2 - 1), x, 0, [0, S(1)/2]).to_expr() + besselj(1, x) + >>> HolonomicFunction((1 + x)*Dx**3 + Dx**2, x, 0, [1, 1, 1]).to_expr() + x*log(x + 1) + log(x + 1) + 1 + + """ + + return hyperexpand(self.to_hyper()).simplify() + + def change_ics(self, b, lenics=None): + """ + Changes the point `x0` to ``b`` for initial conditions. + + Examples + ======== + + >>> from sympy.holonomic import expr_to_holonomic + >>> from sympy import symbols, sin, exp + >>> x = symbols('x') + + >>> expr_to_holonomic(sin(x)).change_ics(1) + HolonomicFunction((1) + (1)*Dx**2, x, 1, [sin(1), cos(1)]) + + >>> expr_to_holonomic(exp(x)).change_ics(2) + HolonomicFunction((-1) + (1)*Dx, x, 2, [exp(2)]) + """ + + symbolic = True + + if lenics is None and len(self.y0) > self.annihilator.order: + lenics = len(self.y0) + dom = self.annihilator.parent.base.domain + + try: + sol = expr_to_holonomic(self.to_expr(), x=self.x, x0=b, lenics=lenics, domain=dom) + except (NotPowerSeriesError, NotHyperSeriesError): + symbolic = False + + if symbolic and sol.x0 == b: + return sol + + y0 = self.evalf(b, derivatives=True) + return HolonomicFunction(self.annihilator, self.x, b, y0) + + def to_meijerg(self): + """ + Returns a linear combination of Meijer G-functions. + + Examples + ======== + + >>> from sympy.holonomic import expr_to_holonomic + >>> from sympy import sin, cos, hyperexpand, log, symbols + >>> x = symbols('x') + >>> hyperexpand(expr_to_holonomic(cos(x) + sin(x)).to_meijerg()) + sin(x) + cos(x) + >>> hyperexpand(expr_to_holonomic(log(x)).to_meijerg()).simplify() + log(x) + + See Also + ======== + + to_hyper + """ + + # convert to hypergeometric first + rep = self.to_hyper(as_list=True) + sol = S.Zero + + for i in rep: + if len(i) == 1: + sol += i[0] + + elif len(i) == 2: + sol += i[0] * _hyper_to_meijerg(i[1]) + + return sol + + +def from_hyper(func, x0=0, evalf=False): + r""" + Converts a hypergeometric function to holonomic. + ``func`` is the Hypergeometric Function and ``x0`` is the point at + which initial conditions are required. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import from_hyper + >>> from sympy import symbols, hyper, S + >>> x = symbols('x') + >>> from_hyper(hyper([], [S(3)/2], x**2/4)) + HolonomicFunction((-x) + (2)*Dx + (x)*Dx**2, x, 1, [sinh(1), -sinh(1) + cosh(1)]) + """ + + a = func.ap + b = func.bq + z = func.args[2] + x = z.atoms(Symbol).pop() + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + + # generalized hypergeometric differential equation + xDx = x*Dx + r1 = 1 + for ai in a: # XXX gives sympify error if Mul is used with list of all factors + r1 *= xDx + ai + xDx_1 = xDx - 1 + # r2 = Mul(*([Dx] + [xDx_1 + bi for bi in b])) # XXX gives sympify error + r2 = Dx + for bi in b: + r2 *= xDx_1 + bi + sol = r1 - r2 + + simp = hyperexpand(func) + + if simp in (Infinity, NegativeInfinity): + return HolonomicFunction(sol, x).composition(z) + + # if the function is known symbolically + if not isinstance(simp, hyper): + y0 = _find_conditions(simp, x, x0, sol.order, use_limit=False) + while not y0: + # if values don't exist at 0, then try to find initial + # conditions at 1. If it doesn't exist at 1 too then + # try 2 and so on. + x0 += 1 + y0 = _find_conditions(simp, x, x0, sol.order, use_limit=False) + + return HolonomicFunction(sol, x).composition(z, x0, y0) + + if isinstance(simp, hyper): + x0 = 1 + # use evalf if the function can't be simplified + y0 = _find_conditions(simp, x, x0, sol.order, evalf, use_limit=False) + while not y0: + x0 += 1 + y0 = _find_conditions(simp, x, x0, sol.order, evalf, use_limit=False) + return HolonomicFunction(sol, x).composition(z, x0, y0) + + return HolonomicFunction(sol, x).composition(z) + + +def from_meijerg(func, x0=0, evalf=False, initcond=True, domain=QQ): + """ + Converts a Meijer G-function to Holonomic. + ``func`` is the G-Function and ``x0`` is the point at + which initial conditions are required. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import from_meijerg + >>> from sympy import symbols, meijerg, S + >>> x = symbols('x') + >>> from_meijerg(meijerg(([], []), ([S(1)/2], [0]), x**2/4)) + HolonomicFunction((1) + (1)*Dx**2, x, 0, [0, 1/sqrt(pi)]) + """ + + a = func.ap + b = func.bq + n = len(func.an) + m = len(func.bm) + p = len(a) + z = func.args[2] + x = z.atoms(Symbol).pop() + R, Dx = DifferentialOperators(domain.old_poly_ring(x), 'Dx') + + # compute the differential equation satisfied by the + # Meijer G-function. + xDx = x*Dx + xDx1 = xDx + 1 + r1 = x*(-1)**(m + n - p) + for ai in a: # XXX gives sympify error if args given in list + r1 *= xDx1 - ai + # r2 = Mul(*[xDx - bi for bi in b]) # gives sympify error + r2 = 1 + for bi in b: + r2 *= xDx - bi + sol = r1 - r2 + + if not initcond: + return HolonomicFunction(sol, x).composition(z) + + simp = hyperexpand(func) + + if simp in (Infinity, NegativeInfinity): + return HolonomicFunction(sol, x).composition(z) + + # computing initial conditions + if not isinstance(simp, meijerg): + y0 = _find_conditions(simp, x, x0, sol.order, use_limit=False) + while not y0: + x0 += 1 + y0 = _find_conditions(simp, x, x0, sol.order, use_limit=False) + + return HolonomicFunction(sol, x).composition(z, x0, y0) + + if isinstance(simp, meijerg): + x0 = 1 + y0 = _find_conditions(simp, x, x0, sol.order, evalf, use_limit=False) + while not y0: + x0 += 1 + y0 = _find_conditions(simp, x, x0, sol.order, evalf, use_limit=False) + + return HolonomicFunction(sol, x).composition(z, x0, y0) + + return HolonomicFunction(sol, x).composition(z) + + +x_1 = Dummy('x_1') +_lookup_table = None +domain_for_table = None +from sympy.integrals.meijerint import _mytype + + +def expr_to_holonomic(func, x=None, x0=0, y0=None, lenics=None, domain=None, initcond=True): + """ + Converts a function or an expression to a holonomic function. + + Parameters + ========== + + func: + The expression to be converted. + x: + variable for the function. + x0: + point at which initial condition must be computed. + y0: + One can optionally provide initial condition if the method + is not able to do it automatically. + lenics: + Number of terms in the initial condition. By default it is + equal to the order of the annihilator. + domain: + Ground domain for the polynomials in ``x`` appearing as coefficients + in the annihilator. + initcond: + Set it false if you do not want the initial conditions to be computed. + + Examples + ======== + + >>> from sympy.holonomic.holonomic import expr_to_holonomic + >>> from sympy import sin, exp, symbols + >>> x = symbols('x') + >>> expr_to_holonomic(sin(x)) + HolonomicFunction((1) + (1)*Dx**2, x, 0, [0, 1]) + >>> expr_to_holonomic(exp(x)) + HolonomicFunction((-1) + (1)*Dx, x, 0, [1]) + + See Also + ======== + + sympy.integrals.meijerint._rewrite1, _convert_poly_rat_alg, _create_table + """ + func = sympify(func) + syms = func.free_symbols + + if not x: + if len(syms) == 1: + x= syms.pop() + else: + raise ValueError("Specify the variable for the function") + elif x in syms: + syms.remove(x) + + extra_syms = list(syms) + + if domain is None: + if func.has(Float): + domain = RR + else: + domain = QQ + if len(extra_syms) != 0: + domain = domain[extra_syms].get_field() + + # try to convert if the function is polynomial or rational + solpoly = _convert_poly_rat_alg(func, x, x0=x0, y0=y0, lenics=lenics, domain=domain, initcond=initcond) + if solpoly: + return solpoly + + # create the lookup table + global _lookup_table, domain_for_table + if not _lookup_table: + domain_for_table = domain + _lookup_table = {} + _create_table(_lookup_table, domain=domain) + elif domain != domain_for_table: + domain_for_table = domain + _lookup_table = {} + _create_table(_lookup_table, domain=domain) + + # use the table directly to convert to Holonomic + if func.is_Function: + f = func.subs(x, x_1) + t = _mytype(f, x_1) + if t in _lookup_table: + l = _lookup_table[t] + sol = l[0][1].change_x(x) + else: + sol = _convert_meijerint(func, x, initcond=False, domain=domain) + if not sol: + raise NotImplementedError + if y0: + sol.y0 = y0 + if y0 or not initcond: + sol.x0 = x0 + return sol + if not lenics: + lenics = sol.annihilator.order + _y0 = _find_conditions(func, x, x0, lenics) + while not _y0: + x0 += 1 + _y0 = _find_conditions(func, x, x0, lenics) + return HolonomicFunction(sol.annihilator, x, x0, _y0) + + if y0 or not initcond: + sol = sol.composition(func.args[0]) + if y0: + sol.y0 = y0 + sol.x0 = x0 + return sol + if not lenics: + lenics = sol.annihilator.order + + _y0 = _find_conditions(func, x, x0, lenics) + while not _y0: + x0 += 1 + _y0 = _find_conditions(func, x, x0, lenics) + return sol.composition(func.args[0], x0, _y0) + + # iterate through the expression recursively + args = func.args + f = func.func + sol = expr_to_holonomic(args[0], x=x, initcond=False, domain=domain) + + if f is Add: + for i in range(1, len(args)): + sol += expr_to_holonomic(args[i], x=x, initcond=False, domain=domain) + + elif f is Mul: + for i in range(1, len(args)): + sol *= expr_to_holonomic(args[i], x=x, initcond=False, domain=domain) + + elif f is Pow: + sol = sol**args[1] + sol.x0 = x0 + if not sol: + raise NotImplementedError + if y0: + sol.y0 = y0 + if y0 or not initcond: + return sol + if sol.y0: + return sol + if not lenics: + lenics = sol.annihilator.order + if sol.annihilator.is_singular(x0): + r = sol._indicial() + l = list(r) + if len(r) == 1 and r[l[0]] == S.One: + r = l[0] + g = func / (x - x0)**r + singular_ics = _find_conditions(g, x, x0, lenics) + singular_ics = [j / factorial(i) for i, j in enumerate(singular_ics)] + y0 = {r:singular_ics} + return HolonomicFunction(sol.annihilator, x, x0, y0) + + _y0 = _find_conditions(func, x, x0, lenics) + while not _y0: + x0 += 1 + _y0 = _find_conditions(func, x, x0, lenics) + + return HolonomicFunction(sol.annihilator, x, x0, _y0) + + +## Some helper functions ## + +def _normalize(list_of, parent, negative=True): + """ + Normalize a given annihilator + """ + + num = [] + denom = [] + base = parent.base + K = base.get_field() + lcm_denom = base.from_sympy(S.One) + list_of_coeff = [] + + # convert polynomials to the elements of associated + # fraction field + for i, j in enumerate(list_of): + if isinstance(j, base.dtype): + list_of_coeff.append(K.new(j.to_list())) + elif not isinstance(j, K.dtype): + list_of_coeff.append(K.from_sympy(sympify(j))) + else: + list_of_coeff.append(j) + + # corresponding numerators of the sequence of polynomials + num.append(list_of_coeff[i].numer()) + + # corresponding denominators + denom.append(list_of_coeff[i].denom()) + + # lcm of denominators in the coefficients + for i in denom: + lcm_denom = i.lcm(lcm_denom) + + if negative: + lcm_denom = -lcm_denom + + lcm_denom = K.new(lcm_denom.to_list()) + + # multiply the coefficients with lcm + for i, j in enumerate(list_of_coeff): + list_of_coeff[i] = j * lcm_denom + + gcd_numer = base((list_of_coeff[-1].numer() / list_of_coeff[-1].denom()).to_list()) + + # gcd of numerators in the coefficients + for i in num: + gcd_numer = i.gcd(gcd_numer) + + gcd_numer = K.new(gcd_numer.to_list()) + + # divide all the coefficients by the gcd + for i, j in enumerate(list_of_coeff): + frac_ans = j / gcd_numer + list_of_coeff[i] = base((frac_ans.numer() / frac_ans.denom()).to_list()) + + return DifferentialOperator(list_of_coeff, parent) + + +def _derivate_diff_eq(listofpoly, K): + """ + Let a differential equation a0(x)y(x) + a1(x)y'(x) + ... = 0 + where a0, a1,... are polynomials or rational functions. The function + returns b0, b1, b2... such that the differential equation + b0(x)y(x) + b1(x)y'(x) +... = 0 is formed after differentiating the + former equation. + """ + + sol = [] + a = len(listofpoly) - 1 + sol.append(DMFdiff(listofpoly[0], K)) + + for i, j in enumerate(listofpoly[1:]): + sol.append(DMFdiff(j, K) + listofpoly[i]) + + sol.append(listofpoly[a]) + return sol + + +def _hyper_to_meijerg(func): + """ + Converts a `hyper` to meijerg. + """ + ap = func.ap + bq = func.bq + + if any(i <= 0 and int(i) == i for i in ap): + return hyperexpand(func) + + z = func.args[2] + + # parameters of the `meijerg` function. + an = (1 - i for i in ap) + anp = () + bm = (S.Zero, ) + bmq = (1 - i for i in bq) + + k = S.One + + for i in bq: + k = k * gamma(i) + + for i in ap: + k = k / gamma(i) + + return k * meijerg(an, anp, bm, bmq, -z) + + +def _add_lists(list1, list2): + """Takes polynomial sequences of two annihilators a and b and returns + the list of polynomials of sum of a and b. + """ + if len(list1) <= len(list2): + sol = [a + b for a, b in zip(list1, list2)] + list2[len(list1):] + else: + sol = [a + b for a, b in zip(list1, list2)] + list1[len(list2):] + return sol + + +def _extend_y0(Holonomic, n): + """ + Tries to find more initial conditions by substituting the initial + value point in the differential equation. + """ + + if Holonomic.annihilator.is_singular(Holonomic.x0) or Holonomic.is_singularics() == True: + return Holonomic.y0 + + annihilator = Holonomic.annihilator + a = annihilator.order + + listofpoly = [] + + y0 = Holonomic.y0 + R = annihilator.parent.base + K = R.get_field() + + for j in annihilator.listofpoly: + if isinstance(j, annihilator.parent.base.dtype): + listofpoly.append(K.new(j.to_list())) + + if len(y0) < a or n <= len(y0): + return y0 + list_red = [-listofpoly[i] / listofpoly[a] + for i in range(a)] + y1 = y0[:min(len(y0), a)] + for _ in range(n - a): + sol = 0 + for a, b in zip(y1, list_red): + r = DMFsubs(b, Holonomic.x0) + if not getattr(r, 'is_finite', True): + return y0 + if isinstance(r, (PolyElement, FracElement)): + r = r.as_expr() + sol += a * r + y1.append(sol) + list_red = _derivate_diff_eq(list_red, K) + return y0 + y1[len(y0):] + + +def DMFdiff(frac, K): + # differentiate a DMF object represented as p/q + if not isinstance(frac, DMF): + return frac.diff() + + p = K.numer(frac) + q = K.denom(frac) + sol_num = - p * q.diff() + q * p.diff() + sol_denom = q**2 + return K((sol_num.to_list(), sol_denom.to_list())) + + +def DMFsubs(frac, x0, mpm=False): + # substitute the point x0 in DMF object of the form p/q + if not isinstance(frac, DMF): + return frac + + p = frac.num + q = frac.den + sol_p = S.Zero + sol_q = S.Zero + + if mpm: + from mpmath import mp + + for i, j in enumerate(reversed(p)): + if mpm: + j = sympify(j)._to_mpmath(mp.prec) + sol_p += j * x0**i + + for i, j in enumerate(reversed(q)): + if mpm: + j = sympify(j)._to_mpmath(mp.prec) + sol_q += j * x0**i + + if isinstance(sol_p, (PolyElement, FracElement)): + sol_p = sol_p.as_expr() + if isinstance(sol_q, (PolyElement, FracElement)): + sol_q = sol_q.as_expr() + + return sol_p / sol_q + + +def _convert_poly_rat_alg(func, x, x0=0, y0=None, lenics=None, domain=QQ, initcond=True): + """ + Converts polynomials, rationals and algebraic functions to holonomic. + """ + + ispoly = func.is_polynomial() + if not ispoly: + israt = func.is_rational_function() + else: + israt = True + + if not (ispoly or israt): + basepoly, ratexp = func.as_base_exp() + if basepoly.is_polynomial() and ratexp.is_Number: + if isinstance(ratexp, Float): + ratexp = nsimplify(ratexp) + m, n = ratexp.p, ratexp.q + is_alg = True + else: + is_alg = False + else: + is_alg = True + + if not (ispoly or israt or is_alg): + return None + + R = domain.old_poly_ring(x) + _, Dx = DifferentialOperators(R, 'Dx') + + # if the function is constant + if not func.has(x): + return HolonomicFunction(Dx, x, 0, [func]) + + if ispoly: + # differential equation satisfied by polynomial + sol = func * Dx - func.diff(x) + sol = _normalize(sol.listofpoly, sol.parent, negative=False) + is_singular = sol.is_singular(x0) + + # try to compute the conditions for singular points + if y0 is None and x0 == 0 and is_singular: + rep = R.from_sympy(func).to_list() + for i, j in enumerate(reversed(rep)): + if j == 0: + continue + coeff = list(reversed(rep))[i:] + indicial = i + break + for i, j in enumerate(coeff): + if isinstance(j, (PolyElement, FracElement)): + coeff[i] = j.as_expr() + y0 = {indicial: S(coeff)} + + elif israt: + p, q = func.as_numer_denom() + # differential equation satisfied by rational + sol = p * q * Dx + p * q.diff(x) - q * p.diff(x) + sol = _normalize(sol.listofpoly, sol.parent, negative=False) + + elif is_alg: + sol = n * (x / m) * Dx - 1 + sol = HolonomicFunction(sol, x).composition(basepoly).annihilator + is_singular = sol.is_singular(x0) + + # try to compute the conditions for singular points + if y0 is None and x0 == 0 and is_singular and \ + (lenics is None or lenics <= 1): + rep = R.from_sympy(basepoly).to_list() + for i, j in enumerate(reversed(rep)): + if j == 0: + continue + if isinstance(j, (PolyElement, FracElement)): + j = j.as_expr() + + coeff = S(j)**ratexp + indicial = S(i) * ratexp + break + if isinstance(coeff, (PolyElement, FracElement)): + coeff = coeff.as_expr() + y0 = {indicial: S([coeff])} + + if y0 or not initcond: + return HolonomicFunction(sol, x, x0, y0) + + if not lenics: + lenics = sol.order + + if sol.is_singular(x0): + r = HolonomicFunction(sol, x, x0)._indicial() + l = list(r) + if len(r) == 1 and r[l[0]] == S.One: + r = l[0] + g = func / (x - x0)**r + singular_ics = _find_conditions(g, x, x0, lenics) + singular_ics = [j / factorial(i) for i, j in enumerate(singular_ics)] + y0 = {r:singular_ics} + return HolonomicFunction(sol, x, x0, y0) + + y0 = _find_conditions(func, x, x0, lenics) + while not y0: + x0 += 1 + y0 = _find_conditions(func, x, x0, lenics) + + return HolonomicFunction(sol, x, x0, y0) + + +def _convert_meijerint(func, x, initcond=True, domain=QQ): + args = meijerint._rewrite1(func, x) + + if args: + fac, po, g, _ = args + else: + return None + + # lists for sum of meijerg functions + fac_list = [fac * i[0] for i in g] + t = po.as_base_exp() + s = t[1] if t[0] == x else S.Zero + po_list = [s + i[1] for i in g] + G_list = [i[2] for i in g] + + # finds meijerg representation of x**s * meijerg(a1 ... ap, b1 ... bq, z) + def _shift(func, s): + z = func.args[-1] + if z.has(I): + z = z.subs(exp_polar, exp) + + d = z.collect(x, evaluate=False) + b = list(d)[0] + a = d[b] + + t = b.as_base_exp() + b = t[1] if t[0] == x else S.Zero + r = s / b + an = (i + r for i in func.args[0][0]) + ap = (i + r for i in func.args[0][1]) + bm = (i + r for i in func.args[1][0]) + bq = (i + r for i in func.args[1][1]) + + return a**-r, meijerg((an, ap), (bm, bq), z) + + coeff, m = _shift(G_list[0], po_list[0]) + sol = fac_list[0] * coeff * from_meijerg(m, initcond=initcond, domain=domain) + + # add all the meijerg functions after converting to holonomic + for i in range(1, len(G_list)): + coeff, m = _shift(G_list[i], po_list[i]) + sol += fac_list[i] * coeff * from_meijerg(m, initcond=initcond, domain=domain) + + return sol + + +def _create_table(table, domain=QQ): + """ + Creates the look-up table. For a similar implementation + see meijerint._create_lookup_table. + """ + + def add(formula, annihilator, arg, x0=0, y0=()): + """ + Adds a formula in the dictionary + """ + table.setdefault(_mytype(formula, x_1), []).append((formula, + HolonomicFunction(annihilator, arg, x0, y0))) + + R = domain.old_poly_ring(x_1) + _, Dx = DifferentialOperators(R, 'Dx') + + # add some basic functions + add(sin(x_1), Dx**2 + 1, x_1, 0, [0, 1]) + add(cos(x_1), Dx**2 + 1, x_1, 0, [1, 0]) + add(exp(x_1), Dx - 1, x_1, 0, 1) + add(log(x_1), Dx + x_1*Dx**2, x_1, 1, [0, 1]) + + add(erf(x_1), 2*x_1*Dx + Dx**2, x_1, 0, [0, 2/sqrt(pi)]) + add(erfc(x_1), 2*x_1*Dx + Dx**2, x_1, 0, [1, -2/sqrt(pi)]) + add(erfi(x_1), -2*x_1*Dx + Dx**2, x_1, 0, [0, 2/sqrt(pi)]) + + add(sinh(x_1), Dx**2 - 1, x_1, 0, [0, 1]) + add(cosh(x_1), Dx**2 - 1, x_1, 0, [1, 0]) + + add(sinc(x_1), x_1 + 2*Dx + x_1*Dx**2, x_1) + + add(Si(x_1), x_1*Dx + 2*Dx**2 + x_1*Dx**3, x_1) + add(Ci(x_1), x_1*Dx + 2*Dx**2 + x_1*Dx**3, x_1) + + add(Shi(x_1), -x_1*Dx + 2*Dx**2 + x_1*Dx**3, x_1) + + +def _find_conditions(func, x, x0, order, evalf=False, use_limit=True): + y0 = [] + for _ in range(order): + val = func.subs(x, x0) + if evalf: + val = val.evalf() + if use_limit and isinstance(val, NaN): + val = limit(func, x, x0) + if val.is_finite is False or isinstance(val, NaN): + return None + y0.append(val) + func = func.diff(x) + return y0 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/holonomicerrors.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/holonomicerrors.py new file mode 100644 index 0000000000000000000000000000000000000000..459a94eb25b186e30b9577d972ebc62a36801f6f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/holonomicerrors.py @@ -0,0 +1,49 @@ +""" Common Exceptions for `holonomic` module. """ + +class BaseHolonomicError(Exception): + + def new(self, *args): + raise NotImplementedError("abstract base class") + +class NotPowerSeriesError(BaseHolonomicError): + + def __init__(self, holonomic, x0): + self.holonomic = holonomic + self.x0 = x0 + + def __str__(self): + s = 'A Power Series does not exists for ' + s += str(self.holonomic) + s += ' about %s.' %self.x0 + return s + +class NotHolonomicError(BaseHolonomicError): + + def __init__(self, m): + self.m = m + + def __str__(self): + return self.m + +class SingularityError(BaseHolonomicError): + + def __init__(self, holonomic, x0): + self.holonomic = holonomic + self.x0 = x0 + + def __str__(self): + s = str(self.holonomic) + s += ' has a singularity at %s.' %self.x0 + return s + +class NotHyperSeriesError(BaseHolonomicError): + + def __init__(self, holonomic, x0): + self.holonomic = holonomic + self.x0 = x0 + + def __str__(self): + s = 'Power series expansion of ' + s += str(self.holonomic) + s += ' about %s is not hypergeometric' %self.x0 + return s diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/numerical.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/numerical.py new file mode 100644 index 0000000000000000000000000000000000000000..418b7c627e2e3d74dcded080a9b6d351cdaa9f3f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/numerical.py @@ -0,0 +1,98 @@ +"""Numerical Methods for Holonomic Functions""" + +from sympy.core.sympify import sympify +from sympy.holonomic.holonomic import DMFsubs + +from mpmath import mp + + +def _evalf(func, points, derivatives=False, method='RK4'): + """ + Numerical methods for numerical integration along a given set of + points in the complex plane. + """ + + ann = func.annihilator + a = ann.order + R = ann.parent.base + K = R.get_field() + + if method == 'Euler': + meth = _euler + else: + meth = _rk4 + + dmf = [K.new(j.to_list()) for j in ann.listofpoly] + red = [-dmf[i] / dmf[a] for i in range(a)] + + y0 = func.y0 + if len(y0) < a: + raise TypeError("Not Enough Initial Conditions") + x0 = func.x0 + sol = [meth(red, x0, points[0], y0, a)] + + for i, j in enumerate(points[1:]): + sol.append(meth(red, points[i], j, sol[-1], a)) + + if not derivatives: + return [sympify(i[0]) for i in sol] + else: + return sympify(sol) + + +def _euler(red, x0, x1, y0, a): + """ + Euler's method for numerical integration. + From x0 to x1 with initial values given at x0 as vector y0. + """ + + A = sympify(x0)._to_mpmath(mp.prec) + B = sympify(x1)._to_mpmath(mp.prec) + y_0 = [sympify(i)._to_mpmath(mp.prec) for i in y0] + h = B - A + f_0 = y_0[1:] + f_0_n = 0 + + for i in range(a): + f_0_n += sympify(DMFsubs(red[i], A, mpm=True))._to_mpmath(mp.prec) * y_0[i] + f_0.append(f_0_n) + + return [y_0[i] + h * f_0[i] for i in range(a)] + + +def _rk4(red, x0, x1, y0, a): + """ + Runge-Kutta 4th order numerical method. + """ + + A = sympify(x0)._to_mpmath(mp.prec) + B = sympify(x1)._to_mpmath(mp.prec) + y_0 = [sympify(i)._to_mpmath(mp.prec) for i in y0] + h = B - A + + f_0_n = 0 + f_1_n = 0 + f_2_n = 0 + f_3_n = 0 + + f_0 = y_0[1:] + for i in range(a): + f_0_n += sympify(DMFsubs(red[i], A, mpm=True))._to_mpmath(mp.prec) * y_0[i] + f_0.append(f_0_n) + + f_1 = [y_0[i] + f_0[i]*h/2 for i in range(1, a)] + for i in range(a): + f_1_n += sympify(DMFsubs(red[i], A + h/2, mpm=True))._to_mpmath(mp.prec) * (y_0[i] + f_0[i]*h/2) + f_1.append(f_1_n) + + f_2 = [y_0[i] + f_1[i]*h/2 for i in range(1, a)] + for i in range(a): + f_2_n += sympify(DMFsubs(red[i], A + h/2, mpm=True))._to_mpmath(mp.prec) * (y_0[i] + f_1[i]*h/2) + f_2.append(f_2_n) + + f_3 = [y_0[i] + f_2[i]*h for i in range(1, a)] + for i in range(a): + f_3_n += sympify(DMFsubs(red[i], A + h, mpm=True))._to_mpmath(mp.prec) * (y_0[i] + f_2[i]*h) + f_3.append(f_3_n) + + return [y_0[i] + h*(f_0[i]+2*f_1[i]+2*f_2[i]+f_3[i])/6 for i in range(a)] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/recurrence.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/recurrence.py new file mode 100644 index 0000000000000000000000000000000000000000..8c2c17ceda2d042c12778977cadd5ce9ee3b7479 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/recurrence.py @@ -0,0 +1,342 @@ +"""Recurrence Operators""" + +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.printing import sstr +from sympy.core.sympify import sympify + + +def RecurrenceOperators(base, generator): + """ + Returns an Algebra of Recurrence Operators and the operator for + shifting i.e. the `Sn` operator. + The first argument needs to be the base polynomial ring for the algebra + and the second argument must be a generator which can be either a + noncommutative Symbol or a string. + + Examples + ======== + + >>> from sympy import ZZ + >>> from sympy import symbols + >>> from sympy.holonomic.recurrence import RecurrenceOperators + >>> n = symbols('n', integer=True) + >>> R, Sn = RecurrenceOperators(ZZ.old_poly_ring(n), 'Sn') + """ + + ring = RecurrenceOperatorAlgebra(base, generator) + return (ring, ring.shift_operator) + + +class RecurrenceOperatorAlgebra: + """ + A Recurrence Operator Algebra is a set of noncommutative polynomials + in intermediate `Sn` and coefficients in a base ring A. It follows the + commutation rule: + Sn * a(n) = a(n + 1) * Sn + + This class represents a Recurrence Operator Algebra and serves as the parent ring + for Recurrence Operators. + + Examples + ======== + + >>> from sympy import ZZ + >>> from sympy import symbols + >>> from sympy.holonomic.recurrence import RecurrenceOperators + >>> n = symbols('n', integer=True) + >>> R, Sn = RecurrenceOperators(ZZ.old_poly_ring(n), 'Sn') + >>> R + Univariate Recurrence Operator Algebra in intermediate Sn over the base ring + ZZ[n] + + See Also + ======== + + RecurrenceOperator + """ + + def __init__(self, base, generator): + # the base ring for the algebra + self.base = base + # the operator representing shift i.e. `Sn` + self.shift_operator = RecurrenceOperator( + [base.zero, base.one], self) + + if generator is None: + self.gen_symbol = symbols('Sn', commutative=False) + else: + if isinstance(generator, str): + self.gen_symbol = symbols(generator, commutative=False) + elif isinstance(generator, Symbol): + self.gen_symbol = generator + + def __str__(self): + string = 'Univariate Recurrence Operator Algebra in intermediate '\ + + sstr(self.gen_symbol) + ' over the base ring ' + \ + (self.base).__str__() + + return string + + __repr__ = __str__ + + def __eq__(self, other): + if self.base == other.base and self.gen_symbol == other.gen_symbol: + return True + else: + return False + + +def _add_lists(list1, list2): + if len(list1) <= len(list2): + sol = [a + b for a, b in zip(list1, list2)] + list2[len(list1):] + else: + sol = [a + b for a, b in zip(list1, list2)] + list1[len(list2):] + return sol + + +class RecurrenceOperator: + """ + The Recurrence Operators are defined by a list of polynomials + in the base ring and the parent ring of the Operator. + + Explanation + =========== + + Takes a list of polynomials for each power of Sn and the + parent ring which must be an instance of RecurrenceOperatorAlgebra. + + A Recurrence Operator can be created easily using + the operator `Sn`. See examples below. + + Examples + ======== + + >>> from sympy.holonomic.recurrence import RecurrenceOperator, RecurrenceOperators + >>> from sympy import ZZ + >>> from sympy import symbols + >>> n = symbols('n', integer=True) + >>> R, Sn = RecurrenceOperators(ZZ.old_poly_ring(n),'Sn') + + >>> RecurrenceOperator([0, 1, n**2], R) + (1)Sn + (n**2)Sn**2 + + >>> Sn*n + (n + 1)Sn + + >>> n*Sn*n + 1 - Sn**2*n + (1) + (n**2 + n)Sn + (-n - 2)Sn**2 + + See Also + ======== + + DifferentialOperatorAlgebra + """ + + _op_priority = 20 + + def __init__(self, list_of_poly, parent): + # the parent ring for this operator + # must be an RecurrenceOperatorAlgebra object + self.parent = parent + # sequence of polynomials in n for each power of Sn + # represents the operator + # convert the expressions into ring elements using from_sympy + if isinstance(list_of_poly, list): + for i, j in enumerate(list_of_poly): + if isinstance(j, int): + list_of_poly[i] = self.parent.base.from_sympy(S(j)) + elif not isinstance(j, self.parent.base.dtype): + list_of_poly[i] = self.parent.base.from_sympy(j) + + self.listofpoly = list_of_poly + self.order = len(self.listofpoly) - 1 + + def __mul__(self, other): + """ + Multiplies two Operators and returns another + RecurrenceOperator instance using the commutation rule + Sn * a(n) = a(n + 1) * Sn + """ + + listofself = self.listofpoly + base = self.parent.base + + if not isinstance(other, RecurrenceOperator): + if not isinstance(other, self.parent.base.dtype): + listofother = [self.parent.base.from_sympy(sympify(other))] + + else: + listofother = [other] + else: + listofother = other.listofpoly + # multiply a polynomial `b` with a list of polynomials + + def _mul_dmp_diffop(b, listofother): + if isinstance(listofother, list): + return [i * b for i in listofother] + return [b * listofother] + + sol = _mul_dmp_diffop(listofself[0], listofother) + + # compute Sn^i * b + def _mul_Sni_b(b): + sol = [base.zero] + + if isinstance(b, list): + for i in b: + j = base.to_sympy(i).subs(base.gens[0], base.gens[0] + S.One) + sol.append(base.from_sympy(j)) + + else: + j = b.subs(base.gens[0], base.gens[0] + S.One) + sol.append(base.from_sympy(j)) + + return sol + + for i in range(1, len(listofself)): + # find Sn^i * b in ith iteration + listofother = _mul_Sni_b(listofother) + # solution = solution + listofself[i] * (Sn^i * b) + sol = _add_lists(sol, _mul_dmp_diffop(listofself[i], listofother)) + + return RecurrenceOperator(sol, self.parent) + + def __rmul__(self, other): + if not isinstance(other, RecurrenceOperator): + + if isinstance(other, int): + other = S(other) + + if not isinstance(other, self.parent.base.dtype): + other = (self.parent.base).from_sympy(other) + + sol = [other * j for j in self.listofpoly] + return RecurrenceOperator(sol, self.parent) + + def __add__(self, other): + if isinstance(other, RecurrenceOperator): + + sol = _add_lists(self.listofpoly, other.listofpoly) + return RecurrenceOperator(sol, self.parent) + + else: + + if isinstance(other, int): + other = S(other) + list_self = self.listofpoly + if not isinstance(other, self.parent.base.dtype): + list_other = [((self.parent).base).from_sympy(other)] + else: + list_other = [other] + sol = [list_self[0] + list_other[0]] + list_self[1:] + + return RecurrenceOperator(sol, self.parent) + + __radd__ = __add__ + + def __sub__(self, other): + return self + (-1) * other + + def __rsub__(self, other): + return (-1) * self + other + + def __pow__(self, n): + if n == 1: + return self + result = RecurrenceOperator([self.parent.base.one], self.parent) + if n == 0: + return result + # if self is `Sn` + if self.listofpoly == self.parent.shift_operator.listofpoly: + sol = [self.parent.base.zero] * n + [self.parent.base.one] + return RecurrenceOperator(sol, self.parent) + x = self + while True: + if n % 2: + result *= x + n >>= 1 + if not n: + break + x *= x + return result + + def __str__(self): + listofpoly = self.listofpoly + print_str = '' + + for i, j in enumerate(listofpoly): + if j == self.parent.base.zero: + continue + + j = self.parent.base.to_sympy(j) + + if i == 0: + print_str += '(' + sstr(j) + ')' + continue + + if print_str: + print_str += ' + ' + + if i == 1: + print_str += '(' + sstr(j) + ')Sn' + continue + + print_str += '(' + sstr(j) + ')' + 'Sn**' + sstr(i) + + return print_str + + __repr__ = __str__ + + def __eq__(self, other): + if isinstance(other, RecurrenceOperator): + if self.listofpoly == other.listofpoly and self.parent == other.parent: + return True + else: + return False + return self.listofpoly[0] == other and \ + all(i is self.parent.base.zero for i in self.listofpoly[1:]) + + +class HolonomicSequence: + """ + A Holonomic Sequence is a type of sequence satisfying a linear homogeneous + recurrence relation with Polynomial coefficients. Alternatively, A sequence + is Holonomic if and only if its generating function is a Holonomic Function. + """ + + def __init__(self, recurrence, u0=[]): + self.recurrence = recurrence + if not isinstance(u0, list): + self.u0 = [u0] + else: + self.u0 = u0 + + if len(self.u0) == 0: + self._have_init_cond = False + else: + self._have_init_cond = True + self.n = recurrence.parent.base.gens[0] + + def __repr__(self): + str_sol = 'HolonomicSequence(%s, %s)' % ((self.recurrence).__repr__(), sstr(self.n)) + if not self._have_init_cond: + return str_sol + else: + cond_str = '' + seq_str = 0 + for i in self.u0: + cond_str += ', u(%s) = %s' % (sstr(seq_str), sstr(i)) + seq_str += 1 + + sol = str_sol + cond_str + return sol + + __str__ = __repr__ + + def __eq__(self, other): + if self.recurrence != other.recurrence or self.n != other.n: + return False + if self._have_init_cond and other._have_init_cond: + return self.u0 == other.u0 + return True diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/tests/test_holonomic.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/tests/test_holonomic.py new file mode 100644 index 0000000000000000000000000000000000000000..49956419e917b3bc81a163d29862c539f33f6284 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/tests/test_holonomic.py @@ -0,0 +1,851 @@ +from sympy.holonomic import (DifferentialOperator, HolonomicFunction, + DifferentialOperators, from_hyper, + from_meijerg, expr_to_holonomic) +from sympy.holonomic.recurrence import RecurrenceOperators, HolonomicSequence +from sympy.core import EulerGamma +from sympy.core.numbers import (I, Rational, pi) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.exponential import (exp, log) +from sympy.functions.elementary.hyperbolic import (asinh, cosh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import (cos, sin) +from sympy.functions.special.bessel import besselj +from sympy.functions.special.beta_functions import beta +from sympy.functions.special.error_functions import (Ci, Si, erf, erfc) +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import (hyper, meijerg) +from sympy.printing.str import sstr +from sympy.series.order import O +from sympy.simplify.hyperexpand import hyperexpand +from sympy.polys.domains.integerring import ZZ +from sympy.polys.domains.rationalfield import QQ +from sympy.polys.domains.realfield import RR + + +def test_DifferentialOperator(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + assert Dx == R.derivative_operator + assert Dx == DifferentialOperator([R.base.zero, R.base.one], R) + assert x * Dx + x**2 * Dx**2 == DifferentialOperator([0, x, x**2], R) + assert (x**2 + 1) + Dx + x * \ + Dx**5 == DifferentialOperator([x**2 + 1, 1, 0, 0, 0, x], R) + assert (x * Dx + x**2 + 1 - Dx * (x**3 + x))**3 == (-48 * x**6) + \ + (-57 * x**7) * Dx + (-15 * x**8) * Dx**2 + (-x**9) * Dx**3 + p = (x * Dx**2 + (x**2 + 3) * Dx**5) * (Dx + x**2) + q = (2 * x) + (4 * x**2) * Dx + (x**3) * Dx**2 + \ + (20 * x**2 + x + 60) * Dx**3 + (10 * x**3 + 30 * x) * Dx**4 + \ + (x**4 + 3 * x**2) * Dx**5 + (x**2 + 3) * Dx**6 + assert p == q + + +def test_HolonomicFunction_addition(): + x = symbols('x') + R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(Dx**2 * x, x) + q = HolonomicFunction((2) * Dx + (x) * Dx**2, x) + assert p == q + p = HolonomicFunction(x * Dx + 1, x) + q = HolonomicFunction(Dx + 1, x) + r = HolonomicFunction((x - 2) + (x**2 - 2) * Dx + (x**2 - x) * Dx**2, x) + assert p + q == r + p = HolonomicFunction(x * Dx + Dx**2 * (x**2 + 2), x) + q = HolonomicFunction(Dx - 3, x) + r = HolonomicFunction((-54 * x**2 - 126 * x - 150) + (-135 * x**3 - 252 * x**2 - 270 * x + 140) * Dx +\ + (-27 * x**4 - 24 * x**2 + 14 * x - 150) * Dx**2 + \ + (9 * x**4 + 15 * x**3 + 38 * x**2 + 30 * x +40) * Dx**3, x) + assert p + q == r + p = HolonomicFunction(Dx**5 - 1, x) + q = HolonomicFunction(x**3 + Dx, x) + r = HolonomicFunction((-x**18 + 45*x**14 - 525*x**10 + 1575*x**6 - x**3 - 630*x**2) + \ + (-x**15 + 30*x**11 - 195*x**7 + 210*x**3 - 1)*Dx + (x**18 - 45*x**14 + 525*x**10 - \ + 1575*x**6 + x**3 + 630*x**2)*Dx**5 + (x**15 - 30*x**11 + 195*x**7 - 210*x**3 + \ + 1)*Dx**6, x) + assert p+q == r + + p = x**2 + 3*x + 8 + q = x**3 - 7*x + 5 + p = p*Dx - p.diff() + q = q*Dx - q.diff() + r = HolonomicFunction(p, x) + HolonomicFunction(q, x) + s = HolonomicFunction((6*x**2 + 18*x + 14) + (-4*x**3 - 18*x**2 - 62*x + 10)*Dx +\ + (x**4 + 6*x**3 + 31*x**2 - 10*x - 71)*Dx**2, x) + assert r == s + + +def test_HolonomicFunction_multiplication(): + x = symbols('x') + R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(Dx+x+x*Dx**2, x) + q = HolonomicFunction(x*Dx+Dx*x+Dx**2, x) + r = HolonomicFunction((8*x**6 + 4*x**4 + 6*x**2 + 3) + (24*x**5 - 4*x**3 + 24*x)*Dx + \ + (8*x**6 + 20*x**4 + 12*x**2 + 2)*Dx**2 + (8*x**5 + 4*x**3 + 4*x)*Dx**3 + \ + (2*x**4 + x**2)*Dx**4, x) + assert p*q == r + p = HolonomicFunction(Dx**2+1, x) + q = HolonomicFunction(Dx-1, x) + r = HolonomicFunction((2) + (-2)*Dx + (1)*Dx**2, x) + assert p*q == r + p = HolonomicFunction(Dx**2+1+x+Dx, x) + q = HolonomicFunction((Dx*x-1)**2, x) + r = HolonomicFunction((4*x**7 + 11*x**6 + 16*x**5 + 4*x**4 - 6*x**3 - 7*x**2 - 8*x - 2) + \ + (8*x**6 + 26*x**5 + 24*x**4 - 3*x**3 - 11*x**2 - 6*x - 2)*Dx + \ + (8*x**6 + 18*x**5 + 15*x**4 - 3*x**3 - 6*x**2 - 6*x - 2)*Dx**2 + (8*x**5 + \ + 10*x**4 + 6*x**3 - 2*x**2 - 4*x)*Dx**3 + (4*x**5 + 3*x**4 - x**2)*Dx**4, x) + assert p*q == r + p = HolonomicFunction(x*Dx**2-1, x) + q = HolonomicFunction(Dx*x-x, x) + r = HolonomicFunction((x - 3) + (-2*x + 2)*Dx + (x)*Dx**2, x) + assert p*q == r + + +def test_HolonomicFunction_power(): + x = symbols('x') + R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(Dx+x+x*Dx**2, x) + a = HolonomicFunction(Dx, x) + for n in range(10): + assert a == p**n + a *= p + + +def test_addition_initial_condition(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(Dx-1, x, 0, [3]) + q = HolonomicFunction(Dx**2+1, x, 0, [1, 0]) + r = HolonomicFunction(-1 + Dx - Dx**2 + Dx**3, x, 0, [4, 3, 2]) + assert p + q == r + p = HolonomicFunction(Dx - x + Dx**2, x, 0, [1, 2]) + q = HolonomicFunction(Dx**2 + x, x, 0, [1, 0]) + r = HolonomicFunction((-x**4 - x**3/4 - x**2 + Rational(1, 4)) + (x**3 + x**2/4 + x*Rational(3, 4) + 1)*Dx + \ + (x*Rational(-3, 2) + Rational(7, 4))*Dx**2 + (x**2 - x*Rational(7, 4) + Rational(1, 4))*Dx**3 + (x**2 + x/4 + S.Half)*Dx**4, x, 0, [2, 2, -2, 2]) + assert p + q == r + p = HolonomicFunction(Dx**2 + 4*x*Dx + x**2, x, 0, [3, 4]) + q = HolonomicFunction(Dx**2 + 1, x, 0, [1, 1]) + r = HolonomicFunction((x**6 + 2*x**4 - 5*x**2 - 6) + (4*x**5 + 36*x**3 - 32*x)*Dx + \ + (x**6 + 3*x**4 + 5*x**2 - 9)*Dx**2 + (4*x**5 + 36*x**3 - 32*x)*Dx**3 + (x**4 + \ + 10*x**2 - 3)*Dx**4, x, 0, [4, 5, -1, -17]) + assert p + q == r + q = HolonomicFunction(Dx**3 + x, x, 2, [3, 0, 1]) + p = HolonomicFunction(Dx - 1, x, 2, [1]) + r = HolonomicFunction((-x**2 - x + 1) + (x**2 + x)*Dx + (-x - 2)*Dx**3 + \ + (x + 1)*Dx**4, x, 2, [4, 1, 2, -5 ]) + assert p + q == r + p = expr_to_holonomic(sin(x)) + q = expr_to_holonomic(1/x, x0=1) + r = HolonomicFunction((x**2 + 6) + (x**3 + 2*x)*Dx + (x**2 + 6)*Dx**2 + (x**3 + 2*x)*Dx**3, \ + x, 1, [sin(1) + 1, -1 + cos(1), -sin(1) + 2]) + assert p + q == r + C_1 = symbols('C_1') + p = expr_to_holonomic(sqrt(x)) + q = expr_to_holonomic(sqrt(x**2-x)) + r = (p + q).to_expr().subs(C_1, -I/2).expand() + assert r == I*sqrt(x)*sqrt(-x + 1) + sqrt(x) + + +def test_multiplication_initial_condition(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(Dx**2 + x*Dx - 1, x, 0, [3, 1]) + q = HolonomicFunction(Dx**2 + 1, x, 0, [1, 1]) + r = HolonomicFunction((x**4 + 14*x**2 + 60) + 4*x*Dx + (x**4 + 9*x**2 + 20)*Dx**2 + \ + (2*x**3 + 18*x)*Dx**3 + (x**2 + 10)*Dx**4, x, 0, [3, 4, 2, 3]) + assert p * q == r + p = HolonomicFunction(Dx**2 + x, x, 0, [1, 0]) + q = HolonomicFunction(Dx**3 - x**2, x, 0, [3, 3, 3]) + r = HolonomicFunction((x**8 - 37*x**7/27 - 10*x**6/27 - 164*x**5/9 - 184*x**4/9 + \ + 160*x**3/27 + 404*x**2/9 + 8*x + Rational(40, 3)) + (6*x**7 - 128*x**6/9 - 98*x**5/9 - 28*x**4/9 + \ + 8*x**3/9 + 28*x**2 + x*Rational(40, 9) - 40)*Dx + (3*x**6 - 82*x**5/9 + 76*x**4/9 + 4*x**3/3 + \ + 220*x**2/9 - x*Rational(80, 3))*Dx**2 + (-2*x**6 + 128*x**5/27 - 2*x**4/3 -80*x**2/9 + Rational(200, 9))*Dx**3 + \ + (3*x**5 - 64*x**4/9 - 28*x**3/9 + 6*x**2 - x*Rational(20, 9) - Rational(20, 3))*Dx**4 + (-4*x**3 + 64*x**2/9 + \ + x*Rational(8, 3))*Dx**5 + (x**4 - 64*x**3/27 - 4*x**2/3 + Rational(20, 9))*Dx**6, x, 0, [3, 3, 3, -3, -12, -24]) + assert p * q == r + p = HolonomicFunction(Dx - 1, x, 0, [2]) + q = HolonomicFunction(Dx**2 + 1, x, 0, [0, 1]) + r = HolonomicFunction(2 -2*Dx + Dx**2, x, 0, [0, 2]) + assert p * q == r + q = HolonomicFunction(x*Dx**2 + 1 + 2*Dx, x, 0,[0, 1]) + r = HolonomicFunction((x - 1) + (-2*x + 2)*Dx + x*Dx**2, x, 0, [0, 2]) + assert p * q == r + p = HolonomicFunction(Dx**2 - 1, x, 0, [1, 3]) + q = HolonomicFunction(Dx**3 + 1, x, 0, [1, 2, 1]) + r = HolonomicFunction(6*Dx + 3*Dx**2 + 2*Dx**3 - 3*Dx**4 + Dx**6, x, 0, [1, 5, 14, 17, 17, 2]) + assert p * q == r + p = expr_to_holonomic(sin(x)) + q = expr_to_holonomic(1/x, x0=1) + r = HolonomicFunction(x + 2*Dx + x*Dx**2, x, 1, [sin(1), -sin(1) + cos(1)]) + assert p * q == r + p = expr_to_holonomic(sqrt(x)) + q = expr_to_holonomic(sqrt(x**2-x)) + r = (p * q).to_expr() + assert r == I*x*sqrt(-x + 1) + + +def test_HolonomicFunction_composition(): + x = symbols('x') + R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(Dx-1, x).composition(x**2+x) + r = HolonomicFunction((-2*x - 1) + Dx, x) + assert p == r + p = HolonomicFunction(Dx**2+1, x).composition(x**5+x**2+1) + r = HolonomicFunction((125*x**12 + 150*x**9 + 60*x**6 + 8*x**3) + (-20*x**3 - 2)*Dx + \ + (5*x**4 + 2*x)*Dx**2, x) + assert p == r + p = HolonomicFunction(Dx**2*x+x, x).composition(2*x**3+x**2+1) + r = HolonomicFunction((216*x**9 + 324*x**8 + 180*x**7 + 152*x**6 + 112*x**5 + \ + 36*x**4 + 4*x**3) + (24*x**4 + 16*x**3 + 3*x**2 - 6*x - 1)*Dx + (6*x**5 + 5*x**4 + \ + x**3 + 3*x**2 + x)*Dx**2, x) + assert p == r + p = HolonomicFunction(Dx**2+1, x).composition(1-x**2) + r = HolonomicFunction((4*x**3) - Dx + x*Dx**2, x) + assert p == r + p = HolonomicFunction(Dx**2+1, x).composition(x - 2/(x**2 + 1)) + r = HolonomicFunction((x**12 + 6*x**10 + 12*x**9 + 15*x**8 + 48*x**7 + 68*x**6 + \ + 72*x**5 + 111*x**4 + 112*x**3 + 54*x**2 + 12*x + 1) + (12*x**8 + 32*x**6 + \ + 24*x**4 - 4)*Dx + (x**12 + 6*x**10 + 4*x**9 + 15*x**8 + 16*x**7 + 20*x**6 + 24*x**5+ \ + 15*x**4 + 16*x**3 + 6*x**2 + 4*x + 1)*Dx**2, x) + assert p == r + + +def test_from_hyper(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + p = hyper([1, 1], [Rational(3, 2)], x**2/4) + q = HolonomicFunction((4*x) + (5*x**2 - 8)*Dx + (x**3 - 4*x)*Dx**2, x, 1, [2*sqrt(3)*pi/9, -4*sqrt(3)*pi/27 + Rational(4, 3)]) + r = from_hyper(p) + assert r == q + p = from_hyper(hyper([1], [Rational(3, 2)], x**2/4)) + q = HolonomicFunction(-x + (-x**2/2 + 2)*Dx + x*Dx**2, x) + # x0 = 1 + y0 = '[sqrt(pi)*exp(1/4)*erf(1/2), -sqrt(pi)*exp(1/4)*erf(1/2)/2 + 1]' + assert sstr(p.y0) == y0 + assert q.annihilator == p.annihilator + + +def test_from_meijerg(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + p = from_meijerg(meijerg(([], [Rational(3, 2)]), ([S.Half], [S.Half, 1]), x)) + q = HolonomicFunction(x/2 - Rational(1, 4) + (-x**2 + x/4)*Dx + x**2*Dx**2 + x**3*Dx**3, x, 1, \ + [1/sqrt(pi), 1/(2*sqrt(pi)), -1/(4*sqrt(pi))]) + assert p == q + p = from_meijerg(meijerg(([], []), ([0], []), x)) + q = HolonomicFunction(1 + Dx, x, 0, [1]) + assert p == q + p = from_meijerg(meijerg(([1], []), ([S.Half], [0]), x)) + q = HolonomicFunction((x + S.Half)*Dx + x*Dx**2, x, 1, [sqrt(pi)*erf(1), exp(-1)]) + assert p == q + p = from_meijerg(meijerg(([0], [1]), ([0], []), 2*x**2)) + q = HolonomicFunction((3*x**2 - 1)*Dx + x**3*Dx**2, x, 1, [-exp(Rational(-1, 2)) + 1, -exp(Rational(-1, 2))]) + assert p == q + + +def test_to_Sequence(): + x = symbols('x') + R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + n = symbols('n', integer=True) + _, Sn = RecurrenceOperators(ZZ.old_poly_ring(n), 'Sn') + p = HolonomicFunction(x**2*Dx**4 + x + Dx, x).to_sequence() + q = [(HolonomicSequence(1 + (n + 2)*Sn**2 + (n**4 + 6*n**3 + 11*n**2 + 6*n)*Sn**3), 0, 1)] + assert p == q + p = HolonomicFunction(x**2*Dx**4 + x**3 + Dx**2, x).to_sequence() + q = [(HolonomicSequence(1 + (n**4 + 14*n**3 + 72*n**2 + 163*n + 140)*Sn**5), 0, 0)] + assert p == q + p = HolonomicFunction(x**3*Dx**4 + 1 + Dx**2, x).to_sequence() + q = [(HolonomicSequence(1 + (n**4 - 2*n**3 - n**2 + 2*n)*Sn + (n**2 + 3*n + 2)*Sn**2), 0, 0)] + assert p == q + p = HolonomicFunction(3*x**3*Dx**4 + 2*x*Dx + x*Dx**3, x).to_sequence() + q = [(HolonomicSequence(2*n + (3*n**4 - 6*n**3 - 3*n**2 + 6*n)*Sn + (n**3 + 3*n**2 + 2*n)*Sn**2), 0, 1)] + assert p == q + + +def test_to_Sequence_Initial_Coniditons(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + n = symbols('n', integer=True) + _, Sn = RecurrenceOperators(QQ.old_poly_ring(n), 'Sn') + p = HolonomicFunction(Dx - 1, x, 0, [1]).to_sequence() + q = [(HolonomicSequence(-1 + (n + 1)*Sn, 1), 0)] + assert p == q + p = HolonomicFunction(Dx**2 + 1, x, 0, [0, 1]).to_sequence() + q = [(HolonomicSequence(1 + (n**2 + 3*n + 2)*Sn**2, [0, 1]), 0)] + assert p == q + p = HolonomicFunction(Dx**2 + 1 + x**3*Dx, x, 0, [2, 3]).to_sequence() + q = [(HolonomicSequence(n + Sn**2 + (n**2 + 7*n + 12)*Sn**4, [2, 3, -1, Rational(-1, 2), Rational(1, 12)]), 1)] + assert p == q + p = HolonomicFunction(x**3*Dx**5 + 1 + Dx, x).to_sequence() + q = [(HolonomicSequence(1 + (n + 1)*Sn + (n**5 - 5*n**3 + 4*n)*Sn**2), 0, 3)] + assert p == q + C_0, C_1, C_2, C_3 = symbols('C_0, C_1, C_2, C_3') + p = expr_to_holonomic(log(1+x**2)) + q = [(HolonomicSequence(n**2 + (n**2 + 2*n)*Sn**2, [0, 0, C_2]), 0, 1)] + assert p.to_sequence() == q + p = p.diff() + q = [(HolonomicSequence((n + 2) + (n + 2)*Sn**2, [C_0, 0]), 1, 0)] + assert p.to_sequence() == q + p = expr_to_holonomic(erf(x) + x).to_sequence() + q = [(HolonomicSequence((2*n**2 - 2*n) + (n**3 + 2*n**2 - n - 2)*Sn**2, [0, 1 + 2/sqrt(pi), 0, C_3]), 0, 2)] + assert p == q + +def test_series(): + x = symbols('x') + R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(Dx**2 + 2*x*Dx, x, 0, [0, 1]).series(n=10) + q = x - x**3/3 + x**5/10 - x**7/42 + x**9/216 + O(x**10) + assert p == q + p = HolonomicFunction(Dx - 1, x).composition(x**2, 0, [1]) # e^(x**2) + q = HolonomicFunction(Dx**2 + 1, x, 0, [1, 0]) # cos(x) + r = (p * q).series(n=10) # expansion of cos(x) * exp(x**2) + s = 1 + x**2/2 + x**4/24 - 31*x**6/720 - 179*x**8/8064 + O(x**10) + assert r == s + t = HolonomicFunction((1 + x)*Dx**2 + Dx, x, 0, [0, 1]) # log(1 + x) + r = (p * t + q).series(n=10) + s = 1 + x - x**2 + 4*x**3/3 - 17*x**4/24 + 31*x**5/30 - 481*x**6/720 +\ + 71*x**7/105 - 20159*x**8/40320 + 379*x**9/840 + O(x**10) + assert r == s + p = HolonomicFunction((6+6*x-3*x**2) - (10*x-3*x**2-3*x**3)*Dx + \ + (4-6*x**3+2*x**4)*Dx**2, x, 0, [0, 1]).series(n=7) + q = x + x**3/6 - 3*x**4/16 + x**5/20 - 23*x**6/960 + O(x**7) + assert p == q + p = HolonomicFunction((6+6*x-3*x**2) - (10*x-3*x**2-3*x**3)*Dx + \ + (4-6*x**3+2*x**4)*Dx**2, x, 0, [1, 0]).series(n=7) + q = 1 - 3*x**2/4 - x**3/4 - 5*x**4/32 - 3*x**5/40 - 17*x**6/384 + O(x**7) + assert p == q + p = expr_to_holonomic(erf(x) + x).series(n=10) + C_3 = symbols('C_3') + q = (erf(x) + x).series(n=10) + assert p.subs(C_3, -2/(3*sqrt(pi))) == q + assert expr_to_holonomic(sqrt(x**3 + x)).series(n=10) == sqrt(x**3 + x).series(n=10) + assert expr_to_holonomic((2*x - 3*x**2)**Rational(1, 3)).series() == ((2*x - 3*x**2)**Rational(1, 3)).series() + assert expr_to_holonomic(sqrt(x**2-x)).series() == (sqrt(x**2-x)).series() + assert expr_to_holonomic(cos(x)**2/x**2, y0={-2: [1, 0, -1]}).series(n=10) == (cos(x)**2/x**2).series(n=10) + assert expr_to_holonomic(cos(x)**2/x**2, x0=1).series(n=10).together() == (cos(x)**2/x**2).series(n=10, x0=1).together() + assert expr_to_holonomic(cos(x-1)**2/(x-1)**2, x0=1, y0={-2: [1, 0, -1]}).series(n=10) \ + == (cos(x-1)**2/(x-1)**2).series(x0=1, n=10) + +def test_evalf_euler(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + + # log(1+x) + p = HolonomicFunction((1 + x)*Dx**2 + Dx, x, 0, [0, 1]) + + # path taken is a straight line from 0 to 1, on the real axis + r = [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1] + s = '0.699525841805253' # approx. equal to log(2) i.e. 0.693147180559945 + assert sstr(p.evalf(r, method='Euler')[-1]) == s + + # path taken is a triangle 0-->1+i-->2 + r = [0.1 + 0.1*I] + for i in range(9): + r.append(r[-1]+0.1+0.1*I) + for i in range(10): + r.append(r[-1]+0.1-0.1*I) + + # close to the exact solution 1.09861228866811 + # imaginary part also close to zero + s = '1.07530466271334 - 0.0251200594793912*I' + assert sstr(p.evalf(r, method='Euler')[-1]) == s + + # sin(x) + p = HolonomicFunction(Dx**2 + 1, x, 0, [0, 1]) + s = '0.905546532085401 - 6.93889390390723e-18*I' + assert sstr(p.evalf(r, method='Euler')[-1]) == s + + # computing sin(pi/2) using this method + # using a linear path from 0 to pi/2 + r = [0.1] + for i in range(14): + r.append(r[-1] + 0.1) + r.append(pi/2) + s = '1.08016557252834' # close to 1.0 (exact solution) + assert sstr(p.evalf(r, method='Euler')[-1]) == s + + # trying different path, a rectangle (0-->i-->pi/2 + i-->pi/2) + # computing the same value sin(pi/2) using different path + r = [0.1*I] + for i in range(9): + r.append(r[-1]+0.1*I) + for i in range(15): + r.append(r[-1]+0.1) + r.append(pi/2+I) + for i in range(10): + r.append(r[-1]-0.1*I) + + # close to 1.0 + s = '0.976882381836257 - 1.65557671738537e-16*I' + assert sstr(p.evalf(r, method='Euler')[-1]) == s + + # cos(x) + p = HolonomicFunction(Dx**2 + 1, x, 0, [1, 0]) + # compute cos(pi) along 0-->pi + r = [0.05] + for i in range(61): + r.append(r[-1]+0.05) + r.append(pi) + # close to -1 (exact answer) + s = '-1.08140824719196' + assert sstr(p.evalf(r, method='Euler')[-1]) == s + + # a rectangular path (0 -> i -> 2+i -> 2) + r = [0.1*I] + for i in range(9): + r.append(r[-1]+0.1*I) + for i in range(20): + r.append(r[-1]+0.1) + for i in range(10): + r.append(r[-1]-0.1*I) + + p = HolonomicFunction(Dx**2 + 1, x, 0, [1,1]).evalf(r, method='Euler') + s = '0.501421652861245 - 3.88578058618805e-16*I' + assert sstr(p[-1]) == s + +def test_evalf_rk4(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + + # log(1+x) + p = HolonomicFunction((1 + x)*Dx**2 + Dx, x, 0, [0, 1]) + + # path taken is a straight line from 0 to 1, on the real axis + r = [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1] + s = '0.693146363174626' # approx. equal to log(2) i.e. 0.693147180559945 + assert sstr(p.evalf(r)[-1]) == s + + # path taken is a triangle 0-->1+i-->2 + r = [0.1 + 0.1*I] + for i in range(9): + r.append(r[-1]+0.1+0.1*I) + for i in range(10): + r.append(r[-1]+0.1-0.1*I) + + # close to the exact solution 1.09861228866811 + # imaginary part also close to zero + s = '1.098616 + 1.36083e-7*I' + assert sstr(p.evalf(r)[-1].n(7)) == s + + # sin(x) + p = HolonomicFunction(Dx**2 + 1, x, 0, [0, 1]) + s = '0.90929463522785 + 1.52655665885959e-16*I' + assert sstr(p.evalf(r)[-1]) == s + + # computing sin(pi/2) using this method + # using a linear path from 0 to pi/2 + r = [0.1] + for i in range(14): + r.append(r[-1] + 0.1) + r.append(pi/2) + s = '0.999999895088917' # close to 1.0 (exact solution) + assert sstr(p.evalf(r)[-1]) == s + + # trying different path, a rectangle (0-->i-->pi/2 + i-->pi/2) + # computing the same value sin(pi/2) using different path + r = [0.1*I] + for i in range(9): + r.append(r[-1]+0.1*I) + for i in range(15): + r.append(r[-1]+0.1) + r.append(pi/2+I) + for i in range(10): + r.append(r[-1]-0.1*I) + + # close to 1.0 + s = '1.00000003415141 + 6.11940487991086e-16*I' + assert sstr(p.evalf(r)[-1]) == s + + # cos(x) + p = HolonomicFunction(Dx**2 + 1, x, 0, [1, 0]) + # compute cos(pi) along 0-->pi + r = [0.05] + for i in range(61): + r.append(r[-1]+0.05) + r.append(pi) + # close to -1 (exact answer) + s = '-0.999999993238714' + assert sstr(p.evalf(r)[-1]) == s + + # a rectangular path (0 -> i -> 2+i -> 2) + r = [0.1*I] + for i in range(9): + r.append(r[-1]+0.1*I) + for i in range(20): + r.append(r[-1]+0.1) + for i in range(10): + r.append(r[-1]-0.1*I) + + p = HolonomicFunction(Dx**2 + 1, x, 0, [1,1]).evalf(r) + s = '0.493152791638442 - 1.41553435639707e-15*I' + assert sstr(p[-1]) == s + + +def test_expr_to_holonomic(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + p = expr_to_holonomic((sin(x)/x)**2) + q = HolonomicFunction(8*x + (4*x**2 + 6)*Dx + 6*x*Dx**2 + x**2*Dx**3, x, 0, \ + [1, 0, Rational(-2, 3)]) + assert p == q + p = expr_to_holonomic(1/(1+x**2)**2) + q = HolonomicFunction(4*x + (x**2 + 1)*Dx, x, 0, [1]) + assert p == q + p = expr_to_holonomic(exp(x)*sin(x)+x*log(1+x)) + q = HolonomicFunction((2*x**3 + 10*x**2 + 20*x + 18) + (-2*x**4 - 10*x**3 - 20*x**2 \ + - 18*x)*Dx + (2*x**5 + 6*x**4 + 7*x**3 + 8*x**2 + 10*x - 4)*Dx**2 + \ + (-2*x**5 - 5*x**4 - 2*x**3 + 2*x**2 - x + 4)*Dx**3 + (x**5 + 2*x**4 - x**3 - \ + 7*x**2/2 + x + Rational(5, 2))*Dx**4, x, 0, [0, 1, 4, -1]) + assert p == q + p = expr_to_holonomic(x*exp(x)+cos(x)+1) + q = HolonomicFunction((-x - 3)*Dx + (x + 2)*Dx**2 + (-x - 3)*Dx**3 + (x + 2)*Dx**4, x, \ + 0, [2, 1, 1, 3]) + assert p == q + assert (x*exp(x)+cos(x)+1).series(n=10) == p.series(n=10) + p = expr_to_holonomic(log(1 + x)**2 + 1) + q = HolonomicFunction(Dx + (3*x + 3)*Dx**2 + (x**2 + 2*x + 1)*Dx**3, x, 0, [1, 0, 2]) + assert p == q + p = expr_to_holonomic(erf(x)**2 + x) + q = HolonomicFunction((8*x**4 - 2*x**2 + 2)*Dx**2 + (6*x**3 - x/2)*Dx**3 + \ + (x**2+ Rational(1, 4))*Dx**4, x, 0, [0, 1, 8/pi, 0]) + assert p == q + p = expr_to_holonomic(cosh(x)*x) + q = HolonomicFunction((-x**2 + 2) -2*x*Dx + x**2*Dx**2, x, 0, [0, 1]) + assert p == q + p = expr_to_holonomic(besselj(2, x)) + q = HolonomicFunction((x**2 - 4) + x*Dx + x**2*Dx**2, x, 0, [0, 0]) + assert p == q + p = expr_to_holonomic(besselj(0, x) + exp(x)) + q = HolonomicFunction((-x**2 - x/2 + S.Half) + (x**2 - x/2 - Rational(3, 2))*Dx + (-x**2 + x/2 + 1)*Dx**2 +\ + (x**2 + x/2)*Dx**3, x, 0, [2, 1, S.Half]) + assert p == q + p = expr_to_holonomic(sin(x)**2/x) + q = HolonomicFunction(4 + 4*x*Dx + 3*Dx**2 + x*Dx**3, x, 0, [0, 1, 0]) + assert p == q + p = expr_to_holonomic(sin(x)**2/x, x0=2) + q = HolonomicFunction((4) + (4*x)*Dx + (3)*Dx**2 + (x)*Dx**3, x, 2, [sin(2)**2/2, + sin(2)*cos(2) - sin(2)**2/4, -3*sin(2)**2/4 + cos(2)**2 - sin(2)*cos(2)]) + assert p == q + p = expr_to_holonomic(log(x)/2 - Ci(2*x)/2 + Ci(2)/2) + q = HolonomicFunction(4*Dx + 4*x*Dx**2 + 3*Dx**3 + x*Dx**4, x, 0, \ + [-log(2)/2 - EulerGamma/2 + Ci(2)/2, 0, 1, 0]) + assert p == q + p = p.to_expr() + q = log(x)/2 - Ci(2*x)/2 + Ci(2)/2 + assert p == q + p = expr_to_holonomic(x**S.Half, x0=1) + q = HolonomicFunction(x*Dx - S.Half, x, 1, [1]) + assert p == q + p = expr_to_holonomic(sqrt(1 + x**2)) + q = HolonomicFunction((-x) + (x**2 + 1)*Dx, x, 0, [1]) + assert p == q + assert (expr_to_holonomic(sqrt(x) + sqrt(2*x)).to_expr()-\ + (sqrt(x) + sqrt(2*x))).simplify() == 0 + assert expr_to_holonomic(3*x+2*sqrt(x)).to_expr() == 3*x+2*sqrt(x) + p = expr_to_holonomic((x**4+x**3+5*x**2+3*x+2)/x**2, lenics=3) + q = HolonomicFunction((-2*x**4 - x**3 + 3*x + 4) + (x**5 + x**4 + 5*x**3 + 3*x**2 + \ + 2*x)*Dx, x, 0, {-2: [2, 3, 5]}) + assert p == q + p = expr_to_holonomic(1/(x-1)**2, lenics=3, x0=1) + q = HolonomicFunction((2) + (x - 1)*Dx, x, 1, {-2: [1, 0, 0]}) + assert p == q + a = symbols("a") + p = expr_to_holonomic(sqrt(a*x), x=x) + assert p.to_expr() == sqrt(a)*sqrt(x) + +def test_to_hyper(): + x = symbols('x') + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(Dx - 2, x, 0, [3]).to_hyper() + q = 3 * hyper([], [], 2*x) + assert p == q + p = hyperexpand(HolonomicFunction((1 + x) * Dx - 3, x, 0, [2]).to_hyper()).expand() + q = 2*x**3 + 6*x**2 + 6*x + 2 + assert p == q + p = HolonomicFunction((1 + x)*Dx**2 + Dx, x, 0, [0, 1]).to_hyper() + q = -x**2*hyper((2, 2, 1), (3, 2), -x)/2 + x + assert p == q + p = HolonomicFunction(2*x*Dx + Dx**2, x, 0, [0, 2/sqrt(pi)]).to_hyper() + q = 2*x*hyper((S.Half,), (Rational(3, 2),), -x**2)/sqrt(pi) + assert p == q + p = hyperexpand(HolonomicFunction(2*x*Dx + Dx**2, x, 0, [1, -2/sqrt(pi)]).to_hyper()) + q = erfc(x) + assert p.rewrite(erfc) == q + p = hyperexpand(HolonomicFunction((x**2 - 1) + x*Dx + x**2*Dx**2, + x, 0, [0, S.Half]).to_hyper()) + q = besselj(1, x) + assert p == q + p = hyperexpand(HolonomicFunction(x*Dx**2 + Dx + x, x, 0, [1, 0]).to_hyper()) + q = besselj(0, x) + assert p == q + +def test_to_expr(): + x = symbols('x') + R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(Dx - 1, x, 0, [1]).to_expr() + q = exp(x) + assert p == q + p = HolonomicFunction(Dx**2 + 1, x, 0, [1, 0]).to_expr() + q = cos(x) + assert p == q + p = HolonomicFunction(Dx**2 - 1, x, 0, [1, 0]).to_expr() + q = cosh(x) + assert p == q + p = HolonomicFunction(2 + (4*x - 1)*Dx + \ + (x**2 - x)*Dx**2, x, 0, [1, 2]).to_expr().expand() + q = 1/(x**2 - 2*x + 1) + assert p == q + p = expr_to_holonomic(sin(x)**2/x).integrate((x, 0, x)).to_expr() + q = (sin(x)**2/x).integrate((x, 0, x)) + assert p == q + C_0, C_1, C_2, C_3 = symbols('C_0, C_1, C_2, C_3') + p = expr_to_holonomic(log(1+x**2)).to_expr() + q = C_2*log(x**2 + 1) + assert p == q + p = expr_to_holonomic(log(1+x**2)).diff().to_expr() + q = C_0*x/(x**2 + 1) + assert p == q + p = expr_to_holonomic(erf(x) + x).to_expr() + q = 3*C_3*x - 3*sqrt(pi)*C_3*erf(x)/2 + x + 2*x/sqrt(pi) + assert p == q + p = expr_to_holonomic(sqrt(x), x0=1).to_expr() + assert p == sqrt(x) + assert expr_to_holonomic(sqrt(x)).to_expr() == sqrt(x) + p = expr_to_holonomic(sqrt(1 + x**2)).to_expr() + assert p == sqrt(1+x**2) + p = expr_to_holonomic((2*x**2 + 1)**Rational(2, 3)).to_expr() + assert p == (2*x**2 + 1)**Rational(2, 3) + p = expr_to_holonomic(sqrt(-x**2+2*x)).to_expr() + assert p == sqrt(x)*sqrt(-x + 2) + p = expr_to_holonomic((-2*x**3+7*x)**Rational(2, 3)).to_expr() + q = x**Rational(2, 3)*(-2*x**2 + 7)**Rational(2, 3) + assert p == q + p = from_hyper(hyper((-2, -3), (S.Half, ), x)) + s = hyperexpand(hyper((-2, -3), (S.Half, ), x)) + D_0 = Symbol('D_0') + C_0 = Symbol('C_0') + assert (p.to_expr().subs({C_0:1, D_0:0}) - s).simplify() == 0 + p.y0 = {0: [1], S.Half: [0]} + assert p.to_expr() == s + assert expr_to_holonomic(x**5).to_expr() == x**5 + assert expr_to_holonomic(2*x**3-3*x**2).to_expr().expand() == \ + 2*x**3-3*x**2 + a = symbols("a") + p = (expr_to_holonomic(1.4*x)*expr_to_holonomic(a*x, x)).to_expr() + q = 1.4*a*x**2 + assert p == q + p = (expr_to_holonomic(1.4*x)+expr_to_holonomic(a*x, x)).to_expr() + q = x*(a + 1.4) + assert p == q + p = (expr_to_holonomic(1.4*x)+expr_to_holonomic(x)).to_expr() + assert p == 2.4*x + + +def test_integrate(): + x = symbols('x') + R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + p = expr_to_holonomic(sin(x)**2/x, x0=1).integrate((x, 2, 3)) + q = '0.166270406994788' + assert sstr(p) == q + p = expr_to_holonomic(sin(x)).integrate((x, 0, x)).to_expr() + q = 1 - cos(x) + assert p == q + p = expr_to_holonomic(sin(x)).integrate((x, 0, 3)) + q = 1 - cos(3) + assert p == q + p = expr_to_holonomic(sin(x)/x, x0=1).integrate((x, 1, 2)) + q = '0.659329913368450' + assert sstr(p) == q + p = expr_to_holonomic(sin(x)**2/x, x0=1).integrate((x, 1, 0)) + q = '-0.423690480850035' + assert sstr(p) == q + p = expr_to_holonomic(sin(x)/x) + assert p.integrate(x).to_expr() == Si(x) + assert p.integrate((x, 0, 2)) == Si(2) + p = expr_to_holonomic(sin(x)**2/x) + q = p.to_expr() + assert p.integrate(x).to_expr() == q.integrate((x, 0, x)) + assert p.integrate((x, 0, 1)) == q.integrate((x, 0, 1)) + assert expr_to_holonomic(1/x, x0=1).integrate(x).to_expr() == log(x) + p = expr_to_holonomic((x + 1)**3*exp(-x), x0=-1).integrate(x).to_expr() + q = (-x**3 - 6*x**2 - 15*x + 6*exp(x + 1) - 16)*exp(-x) + assert p == q + p = expr_to_holonomic(cos(x)**2/x**2, y0={-2: [1, 0, -1]}).integrate(x).to_expr() + q = -Si(2*x) - cos(x)**2/x + assert p == q + p = expr_to_holonomic(sqrt(x**2+x)).integrate(x).to_expr() + q = (x**Rational(3, 2)*(2*x**2 + 3*x + 1) - x*sqrt(x + 1)*asinh(sqrt(x)))/(4*x*sqrt(x + 1)) + assert p == q + p = expr_to_holonomic(sqrt(x**2+1)).integrate(x).to_expr() + q = (sqrt(x**2+1)).integrate(x) + assert (p-q).simplify() == 0 + p = expr_to_holonomic(1/x**2, y0={-2:[1, 0, 0]}) + r = expr_to_holonomic(1/x**2, lenics=3) + assert p == r + q = expr_to_holonomic(cos(x)**2) + assert (r*q).integrate(x).to_expr() == -Si(2*x) - cos(x)**2/x + + +def test_diff(): + x, y = symbols('x, y') + R, Dx = DifferentialOperators(ZZ.old_poly_ring(x), 'Dx') + p = HolonomicFunction(x*Dx**2 + 1, x, 0, [0, 1]) + assert p.diff().to_expr() == p.to_expr().diff().simplify() + p = HolonomicFunction(Dx**2 - 1, x, 0, [1, 0]) + assert p.diff(x, 2).to_expr() == p.to_expr() + p = expr_to_holonomic(Si(x)) + assert p.diff().to_expr() == sin(x)/x + assert p.diff(y) == 0 + C_0, C_1, C_2, C_3 = symbols('C_0, C_1, C_2, C_3') + q = Si(x) + assert p.diff(x).to_expr() == q.diff() + assert p.diff(x, 2).to_expr().subs(C_0, Rational(-1, 3)).cancel() == q.diff(x, 2).cancel() + assert p.diff(x, 3).series().subs({C_3: Rational(-1, 3), C_0: 0}) == q.diff(x, 3).series() + + +def test_extended_domain_in_expr_to_holonomic(): + x = symbols('x') + p = expr_to_holonomic(1.2*cos(3.1*x)) + assert p.to_expr() == 1.2*cos(3.1*x) + assert sstr(p.integrate(x).to_expr()) == '0.387096774193548*sin(3.1*x)' + _, Dx = DifferentialOperators(RR.old_poly_ring(x), 'Dx') + p = expr_to_holonomic(1.1329138213*x) + q = HolonomicFunction((-1.1329138213) + (1.1329138213*x)*Dx, x, 0, {1: [1.1329138213]}) + assert p == q + assert p.to_expr() == 1.1329138213*x + assert sstr(p.integrate((x, 1, 2))) == sstr((1.1329138213*x).integrate((x, 1, 2))) + y, z = symbols('y, z') + p = expr_to_holonomic(sin(x*y*z), x=x) + assert p.to_expr() == sin(x*y*z) + assert p.integrate(x).to_expr() == (-cos(x*y*z) + 1)/(y*z) + p = expr_to_holonomic(sin(x*y + z), x=x).integrate(x).to_expr() + q = (cos(z) - cos(x*y + z))/y + assert p == q + a = symbols('a') + p = expr_to_holonomic(a*x, x) + assert p.to_expr() == a*x + assert p.integrate(x).to_expr() == a*x**2/2 + D_2, C_1 = symbols("D_2, C_1") + p = expr_to_holonomic(x) + expr_to_holonomic(1.2*cos(x)) + p = p.to_expr().subs(D_2, 0) + assert p - x - 1.2*cos(1.0*x) == 0 + p = expr_to_holonomic(x) * expr_to_holonomic(1.2*cos(x)) + p = p.to_expr().subs(C_1, 0) + assert p - 1.2*x*cos(1.0*x) == 0 + + +def test_to_meijerg(): + x = symbols('x') + assert hyperexpand(expr_to_holonomic(sin(x)).to_meijerg()) == sin(x) + assert hyperexpand(expr_to_holonomic(cos(x)).to_meijerg()) == cos(x) + assert hyperexpand(expr_to_holonomic(exp(x)).to_meijerg()) == exp(x) + assert hyperexpand(expr_to_holonomic(log(x)).to_meijerg()).simplify() == log(x) + assert expr_to_holonomic(4*x**2/3 + 7).to_meijerg() == 4*x**2/3 + 7 + assert hyperexpand(expr_to_holonomic(besselj(2, x), lenics=3).to_meijerg()) == besselj(2, x) + p = hyper((Rational(-1, 2), -3), (), x) + assert from_hyper(p).to_meijerg() == hyperexpand(p) + p = hyper((S.One, S(3)), (S(2), ), x) + assert (hyperexpand(from_hyper(p).to_meijerg()) - hyperexpand(p)).expand() == 0 + p = from_hyper(hyper((-2, -3), (S.Half, ), x)) + s = hyperexpand(hyper((-2, -3), (S.Half, ), x)) + C_0 = Symbol('C_0') + C_1 = Symbol('C_1') + D_0 = Symbol('D_0') + assert (hyperexpand(p.to_meijerg()).subs({C_0:1, D_0:0}) - s).simplify() == 0 + p.y0 = {0: [1], S.Half: [0]} + assert (hyperexpand(p.to_meijerg()) - s).simplify() == 0 + p = expr_to_holonomic(besselj(S.Half, x), initcond=False) + assert (p.to_expr() - (D_0*sin(x) + C_0*cos(x) + C_1*sin(x))/sqrt(x)).simplify() == 0 + p = expr_to_holonomic(besselj(S.Half, x), y0={Rational(-1, 2): [sqrt(2)/sqrt(pi), sqrt(2)/sqrt(pi)]}) + assert (p.to_expr() - besselj(S.Half, x) - besselj(Rational(-1, 2), x)).simplify() == 0 + + +def test_gaussian(): + mu, x = symbols("mu x") + sd = symbols("sd", positive=True) + Q = QQ[mu, sd].get_field() + e = sqrt(2)*exp(-(-mu + x)**2/(2*sd**2))/(2*sqrt(pi)*sd) + h1 = expr_to_holonomic(e, x, domain=Q) + + _, Dx = DifferentialOperators(Q.old_poly_ring(x), 'Dx') + h2 = HolonomicFunction((-mu/sd**2 + x/sd**2) + (1)*Dx, x) + + assert h1 == h2 + + +def test_beta(): + a, b, x = symbols("a b x", positive=True) + e = x**(a - 1)*(-x + 1)**(b - 1)/beta(a, b) + Q = QQ[a, b].get_field() + h1 = expr_to_holonomic(e, x, domain=Q) + + _, Dx = DifferentialOperators(Q.old_poly_ring(x), 'Dx') + h2 = HolonomicFunction((a + x*(-a - b + 2) - 1) + (x**2 - x)*Dx, x) + + assert h1 == h2 + + +def test_gamma(): + a, b, x = symbols("a b x", positive=True) + e = b**(-a)*x**(a - 1)*exp(-x/b)/gamma(a) + Q = QQ[a, b].get_field() + h1 = expr_to_holonomic(e, x, domain=Q) + + _, Dx = DifferentialOperators(Q.old_poly_ring(x), 'Dx') + h2 = HolonomicFunction((-a + 1 + x/b) + (x)*Dx, x) + + assert h1 == h2 + + +def test_symbolic_power(): + x, n = symbols("x n") + Q = QQ[n].get_field() + _, Dx = DifferentialOperators(Q.old_poly_ring(x), 'Dx') + h1 = HolonomicFunction((-1) + (x)*Dx, x) ** -n + h2 = HolonomicFunction((n) + (x)*Dx, x) + + assert h1 == h2 + + +def test_negative_power(): + x = symbols("x") + _, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + h1 = HolonomicFunction((-1) + (x)*Dx, x) ** -2 + h2 = HolonomicFunction((2) + (x)*Dx, x) + + assert h1 == h2 + + +def test_expr_in_power(): + x, n = symbols("x n") + Q = QQ[n].get_field() + _, Dx = DifferentialOperators(Q.old_poly_ring(x), 'Dx') + h1 = HolonomicFunction((-1) + (x)*Dx, x) ** (n - 3) + h2 = HolonomicFunction((-n + 3) + (x)*Dx, x) + + assert h1 == h2 + + +def test_DifferentialOperatorEqPoly(): + x = symbols('x', integer=True) + R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + do = DifferentialOperator([x**2, R.base.zero, R.base.zero], R) + do2 = DifferentialOperator([x**2, 1, x], R) + assert not do == do2 + + # polynomial comparison issue, see https://github.com/sympy/sympy/pull/15799 + # should work once that is solved + # p = do.listofpoly[0] + # assert do == p + + p2 = do2.listofpoly[0] + assert not do2 == p2 + + +def test_DifferentialOperatorPow(): + x = symbols('x', integer=True) + R, _ = DifferentialOperators(QQ.old_poly_ring(x), 'Dx') + do = DifferentialOperator([x**2, R.base.zero, R.base.zero], R) + a = DifferentialOperator([R.base.one], R) + for n in range(10): + assert a == do**n + a *= do diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/tests/test_recurrence.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/tests/test_recurrence.py new file mode 100644 index 0000000000000000000000000000000000000000..526595e91c5fc507877275e3e53e78c6f3716095 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/holonomic/tests/test_recurrence.py @@ -0,0 +1,41 @@ +from sympy.holonomic.recurrence import RecurrenceOperators, RecurrenceOperator +from sympy.core.symbol import symbols +from sympy.polys.domains.rationalfield import QQ + + +def test_RecurrenceOperator(): + n = symbols('n', integer=True) + R, Sn = RecurrenceOperators(QQ.old_poly_ring(n), 'Sn') + assert Sn*n == (n + 1)*Sn + assert Sn*n**2 == (n**2+1+2*n)*Sn + assert Sn**2*n**2 == (n**2 + 4*n + 4)*Sn**2 + p = (Sn**3*n**2 + Sn*n)**2 + q = (n**2 + 3*n + 2)*Sn**2 + (2*n**3 + 19*n**2 + 57*n + 52)*Sn**4 + (n**4 + 18*n**3 + \ + 117*n**2 + 324*n + 324)*Sn**6 + assert p == q + + +def test_RecurrenceOperatorEqPoly(): + n = symbols('n', integer=True) + R, Sn = RecurrenceOperators(QQ.old_poly_ring(n), 'Sn') + rr = RecurrenceOperator([n**2, 0, 0], R) + rr2 = RecurrenceOperator([n**2, 1, n], R) + assert not rr == rr2 + + # polynomial comparison issue, see https://github.com/sympy/sympy/pull/15799 + # should work once that is solved + # d = rr.listofpoly[0] + # assert rr == d + + d2 = rr2.listofpoly[0] + assert not rr2 == d2 + + +def test_RecurrenceOperatorPow(): + n = symbols('n', integer=True) + R, _ = RecurrenceOperators(QQ.old_poly_ring(n), 'Sn') + rr = RecurrenceOperator([n**2, 0, 0], R) + a = RecurrenceOperator([R.base.one], R) + for m in range(10): + assert a == rr**m + a *= rr diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e78fe96f84d68e9b119571eb22dedb7033811b23 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/__init__.py @@ -0,0 +1,45 @@ +"""Integration functions that integrate a SymPy expression. + + Examples + ======== + + >>> from sympy import integrate, sin + >>> from sympy.abc import x + >>> integrate(1/x,x) + log(x) + >>> integrate(sin(x),x) + -cos(x) +""" +from .integrals import integrate, Integral, line_integrate +from .transforms import (mellin_transform, inverse_mellin_transform, + MellinTransform, InverseMellinTransform, + laplace_transform, inverse_laplace_transform, + laplace_correspondence, laplace_initial_conds, + LaplaceTransform, InverseLaplaceTransform, + fourier_transform, inverse_fourier_transform, + FourierTransform, InverseFourierTransform, + sine_transform, inverse_sine_transform, + SineTransform, InverseSineTransform, + cosine_transform, inverse_cosine_transform, + CosineTransform, InverseCosineTransform, + hankel_transform, inverse_hankel_transform, + HankelTransform, InverseHankelTransform) +from .singularityfunctions import singularityintegrate + +__all__ = [ + 'integrate', 'Integral', 'line_integrate', + + 'mellin_transform', 'inverse_mellin_transform', 'MellinTransform', + 'InverseMellinTransform', 'laplace_transform', + 'inverse_laplace_transform', 'LaplaceTransform', + 'laplace_correspondence', 'laplace_initial_conds', + 'InverseLaplaceTransform', 'fourier_transform', + 'inverse_fourier_transform', 'FourierTransform', + 'InverseFourierTransform', 'sine_transform', 'inverse_sine_transform', + 'SineTransform', 'InverseSineTransform', 'cosine_transform', + 'inverse_cosine_transform', 'CosineTransform', 'InverseCosineTransform', + 'hankel_transform', 'inverse_hankel_transform', 'HankelTransform', + 'InverseHankelTransform', + + 'singularityintegrate', +] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/benchmarks/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/benchmarks/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/benchmarks/bench_integrate.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/benchmarks/bench_integrate.py new file mode 100644 index 0000000000000000000000000000000000000000..833bc57403b34df1e75c798084ffc4d8afe9eae6 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/benchmarks/bench_integrate.py @@ -0,0 +1,21 @@ +from sympy.core.symbol import Symbol +from sympy.functions.elementary.trigonometric import sin +from sympy.integrals.integrals import integrate + +x = Symbol('x') + + +def bench_integrate_sin(): + integrate(sin(x), x) + + +def bench_integrate_x1sin(): + integrate(x**1*sin(x), x) + + +def bench_integrate_x2sin(): + integrate(x**2*sin(x), x) + + +def bench_integrate_x3sin(): + integrate(x**3*sin(x), x) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/benchmarks/bench_trigintegrate.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/benchmarks/bench_trigintegrate.py new file mode 100644 index 0000000000000000000000000000000000000000..403c5471b8048ff2aa97bf2f837b9ea05f0fd904 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/benchmarks/bench_trigintegrate.py @@ -0,0 +1,13 @@ +from sympy.core.symbol import Symbol +from sympy.functions.elementary.trigonometric import sin +from sympy.integrals.trigonometry import trigintegrate + +x = Symbol('x') + + +def timeit_trigintegrate_sin3x(): + trigintegrate(sin(x)**3, x) + + +def timeit_trigintegrate_x2(): + trigintegrate(x**2, x) # -> None diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/deltafunctions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/deltafunctions.py new file mode 100644 index 0000000000000000000000000000000000000000..ae9fef0b0010a313e0866a54d978024dd475f882 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/deltafunctions.py @@ -0,0 +1,201 @@ +from sympy.core.mul import Mul +from sympy.core.singleton import S +from sympy.core.sorting import default_sort_key +from sympy.functions import DiracDelta, Heaviside +from .integrals import Integral, integrate + + +def change_mul(node, x): + """change_mul(node, x) + + Rearranges the operands of a product, bringing to front any simple + DiracDelta expression. + + Explanation + =========== + + If no simple DiracDelta expression was found, then all the DiracDelta + expressions are simplified (using DiracDelta.expand(diracdelta=True, wrt=x)). + + Return: (dirac, new node) + Where: + o dirac is either a simple DiracDelta expression or None (if no simple + expression was found); + o new node is either a simplified DiracDelta expressions or None (if it + could not be simplified). + + Examples + ======== + + >>> from sympy import DiracDelta, cos + >>> from sympy.integrals.deltafunctions import change_mul + >>> from sympy.abc import x, y + >>> change_mul(x*y*DiracDelta(x)*cos(x), x) + (DiracDelta(x), x*y*cos(x)) + >>> change_mul(x*y*DiracDelta(x**2 - 1)*cos(x), x) + (None, x*y*cos(x)*DiracDelta(x - 1)/2 + x*y*cos(x)*DiracDelta(x + 1)/2) + >>> change_mul(x*y*DiracDelta(cos(x))*cos(x), x) + (None, None) + + See Also + ======== + + sympy.functions.special.delta_functions.DiracDelta + deltaintegrate + """ + + new_args = [] + dirac = None + + #Sorting is needed so that we consistently collapse the same delta; + #However, we must preserve the ordering of non-commutative terms + c, nc = node.args_cnc() + sorted_args = sorted(c, key=default_sort_key) + sorted_args.extend(nc) + + for arg in sorted_args: + if arg.is_Pow and isinstance(arg.base, DiracDelta): + new_args.append(arg.func(arg.base, arg.exp - 1)) + arg = arg.base + if dirac is None and (isinstance(arg, DiracDelta) and arg.is_simple(x)): + dirac = arg + else: + new_args.append(arg) + if not dirac: # there was no simple dirac + new_args = [] + for arg in sorted_args: + if isinstance(arg, DiracDelta): + new_args.append(arg.expand(diracdelta=True, wrt=x)) + elif arg.is_Pow and isinstance(arg.base, DiracDelta): + new_args.append(arg.func(arg.base.expand(diracdelta=True, wrt=x), arg.exp)) + else: + new_args.append(arg) + if new_args != sorted_args: + nnode = Mul(*new_args).expand() + else: # if the node didn't change there is nothing to do + nnode = None + return (None, nnode) + return (dirac, Mul(*new_args)) + + +def deltaintegrate(f, x): + """ + deltaintegrate(f, x) + + Explanation + =========== + + The idea for integration is the following: + + - If we are dealing with a DiracDelta expression, i.e. DiracDelta(g(x)), + we try to simplify it. + + If we could simplify it, then we integrate the resulting expression. + We already know we can integrate a simplified expression, because only + simple DiracDelta expressions are involved. + + If we couldn't simplify it, there are two cases: + + 1) The expression is a simple expression: we return the integral, + taking care if we are dealing with a Derivative or with a proper + DiracDelta. + + 2) The expression is not simple (i.e. DiracDelta(cos(x))): we can do + nothing at all. + + - If the node is a multiplication node having a DiracDelta term: + + First we expand it. + + If the expansion did work, then we try to integrate the expansion. + + If not, we try to extract a simple DiracDelta term, then we have two + cases: + + 1) We have a simple DiracDelta term, so we return the integral. + + 2) We didn't have a simple term, but we do have an expression with + simplified DiracDelta terms, so we integrate this expression. + + Examples + ======== + + >>> from sympy.abc import x, y, z + >>> from sympy.integrals.deltafunctions import deltaintegrate + >>> from sympy import sin, cos, DiracDelta + >>> deltaintegrate(x*sin(x)*cos(x)*DiracDelta(x - 1), x) + sin(1)*cos(1)*Heaviside(x - 1) + >>> deltaintegrate(y**2*DiracDelta(x - z)*DiracDelta(y - z), y) + z**2*DiracDelta(x - z)*Heaviside(y - z) + + See Also + ======== + + sympy.functions.special.delta_functions.DiracDelta + sympy.integrals.integrals.Integral + """ + if not f.has(DiracDelta): + return None + + # g(x) = DiracDelta(h(x)) + if f.func == DiracDelta: + h = f.expand(diracdelta=True, wrt=x) + if h == f: # can't simplify the expression + #FIXME: the second term tells whether is DeltaDirac or Derivative + #For integrating derivatives of DiracDelta we need the chain rule + if f.is_simple(x): + if (len(f.args) <= 1 or f.args[1] == 0): + return Heaviside(f.args[0]) + else: + return (DiracDelta(f.args[0], f.args[1] - 1) / + f.args[0].as_poly().LC()) + else: # let's try to integrate the simplified expression + fh = integrate(h, x) + return fh + elif f.is_Mul or f.is_Pow: # g(x) = a*b*c*f(DiracDelta(h(x)))*d*e + g = f.expand() + if f != g: # the expansion worked + fh = integrate(g, x) + if fh is not None and not isinstance(fh, Integral): + return fh + else: + # no expansion performed, try to extract a simple DiracDelta term + deltaterm, rest_mult = change_mul(f, x) + + if not deltaterm: + if rest_mult: + fh = integrate(rest_mult, x) + return fh + else: + from sympy.solvers import solve + deltaterm = deltaterm.expand(diracdelta=True, wrt=x) + if deltaterm.is_Mul: # Take out any extracted factors + deltaterm, rest_mult_2 = change_mul(deltaterm, x) + rest_mult = rest_mult*rest_mult_2 + point = solve(deltaterm.args[0], x)[0] + + # Return the largest hyperreal term left after + # repeated integration by parts. For example, + # + # integrate(y*DiracDelta(x, 1),x) == y*DiracDelta(x,0), not 0 + # + # This is so Integral(y*DiracDelta(x).diff(x),x).doit() + # will return y*DiracDelta(x) instead of 0 or DiracDelta(x), + # both of which are correct everywhere the value is defined + # but give wrong answers for nested integration. + n = (0 if len(deltaterm.args)==1 else deltaterm.args[1]) + m = 0 + while n >= 0: + r = S.NegativeOne**n*rest_mult.diff(x, n).subs(x, point) + if r.is_zero: + n -= 1 + m += 1 + else: + if m == 0: + return r*Heaviside(x - point) + else: + return r*DiracDelta(x,m-1) + # In some very weak sense, x=0 is still a singularity, + # but we hope will not be of any practical consequence. + return S.Zero + return None diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/heurisch.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/heurisch.py new file mode 100644 index 0000000000000000000000000000000000000000..a27e2700afd08db16c7a86020eabe5feeb6e1c85 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/heurisch.py @@ -0,0 +1,781 @@ +from __future__ import annotations + +from collections import defaultdict +from functools import reduce +from itertools import permutations + +from sympy.core.add import Add +from sympy.core.basic import Basic +from sympy.core.mul import Mul +from sympy.core.symbol import Wild, Dummy, Symbol +from sympy.core.basic import sympify +from sympy.core.numbers import Rational, pi, I +from sympy.core.relational import Eq, Ne +from sympy.core.singleton import S +from sympy.core.sorting import ordered +from sympy.core.traversal import iterfreeargs + +from sympy.functions import exp, sin, cos, tan, cot, asin, atan +from sympy.functions import log, sinh, cosh, tanh, coth, asinh +from sympy.functions import sqrt, erf, erfi, li, Ei +from sympy.functions import besselj, bessely, besseli, besselk +from sympy.functions import hankel1, hankel2, jn, yn +from sympy.functions.elementary.complexes import Abs, re, im, sign, arg +from sympy.functions.elementary.exponential import LambertW +from sympy.functions.elementary.integers import floor, ceiling +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.special.delta_functions import Heaviside, DiracDelta + +from sympy.simplify.radsimp import collect + +from sympy.logic.boolalg import And, Or +from sympy.utilities.iterables import uniq + +from sympy.polys import quo, gcd, lcm, factor_list, cancel, PolynomialError +from sympy.polys.monomials import itermonomials +from sympy.polys.polyroots import root_factors + +from sympy.polys.rings import PolyRing +from sympy.polys.solvers import solve_lin_sys +from sympy.polys.constructor import construct_domain + +from sympy.integrals.integrals import integrate + + +def components(f, x): + """ + Returns a set of all functional components of the given expression + which includes symbols, function applications and compositions and + non-integer powers. Fractional powers are collected with + minimal, positive exponents. + + Examples + ======== + + >>> from sympy import cos, sin + >>> from sympy.abc import x + >>> from sympy.integrals.heurisch import components + + >>> components(sin(x)*cos(x)**2, x) + {x, sin(x), cos(x)} + + See Also + ======== + + heurisch + """ + result = set() + + if f.has_free(x): + if f.is_symbol and f.is_commutative: + result.add(f) + elif f.is_Function or f.is_Derivative: + for g in f.args: + result |= components(g, x) + + result.add(f) + elif f.is_Pow: + result |= components(f.base, x) + + if not f.exp.is_Integer: + if f.exp.is_Rational: + result.add(f.base**Rational(1, f.exp.q)) + else: + result |= components(f.exp, x) | {f} + else: + for g in f.args: + result |= components(g, x) + + return result + +# name -> [] of symbols +_symbols_cache: dict[str, list[Dummy]] = {} + + +# NB @cacheit is not convenient here +def _symbols(name, n): + """get vector of symbols local to this module""" + try: + lsyms = _symbols_cache[name] + except KeyError: + lsyms = [] + _symbols_cache[name] = lsyms + + while len(lsyms) < n: + lsyms.append( Dummy('%s%i' % (name, len(lsyms))) ) + + return lsyms[:n] + + +def heurisch_wrapper(f, x, rewrite=False, hints=None, mappings=None, retries=3, + degree_offset=0, unnecessary_permutations=None, + _try_heurisch=None): + """ + A wrapper around the heurisch integration algorithm. + + Explanation + =========== + + This method takes the result from heurisch and checks for poles in the + denominator. For each of these poles, the integral is reevaluated, and + the final integration result is given in terms of a Piecewise. + + Examples + ======== + + >>> from sympy import cos, symbols + >>> from sympy.integrals.heurisch import heurisch, heurisch_wrapper + >>> n, x = symbols('n x') + >>> heurisch(cos(n*x), x) + sin(n*x)/n + >>> heurisch_wrapper(cos(n*x), x) + Piecewise((sin(n*x)/n, Ne(n, 0)), (x, True)) + + See Also + ======== + + heurisch + """ + from sympy.solvers.solvers import solve, denoms + f = sympify(f) + if not f.has_free(x): + return f*x + + res = heurisch(f, x, rewrite, hints, mappings, retries, degree_offset, + unnecessary_permutations, _try_heurisch) + if not isinstance(res, Basic): + return res + + # We consider each denominator in the expression, and try to find + # cases where one or more symbolic denominator might be zero. The + # conditions for these cases are stored in the list slns. + # + # Since denoms returns a set we use ordered. This is important because the + # ordering of slns determines the order of the resulting Piecewise so we + # need a deterministic order here to make the output deterministic. + slns = [] + for d in ordered(denoms(res)): + try: + slns += solve([d], dict=True, exclude=(x,)) + except NotImplementedError: + pass + if not slns: + return res + slns = list(uniq(slns)) + # Remove the solutions corresponding to poles in the original expression. + slns0 = [] + for d in denoms(f): + try: + slns0 += solve([d], dict=True, exclude=(x,)) + except NotImplementedError: + pass + slns = [s for s in slns if s not in slns0] + if not slns: + return res + if len(slns) > 1: + eqs = [] + for sub_dict in slns: + eqs.extend([Eq(key, value) for key, value in sub_dict.items()]) + slns = solve(eqs, dict=True, exclude=(x,)) + slns + # For each case listed in the list slns, we reevaluate the integral. + pairs = [] + for sub_dict in slns: + expr = heurisch(f.subs(sub_dict), x, rewrite, hints, mappings, retries, + degree_offset, unnecessary_permutations, + _try_heurisch) + cond = And(*[Eq(key, value) for key, value in sub_dict.items()]) + generic = Or(*[Ne(key, value) for key, value in sub_dict.items()]) + if expr is None: + expr = integrate(f.subs(sub_dict),x) + pairs.append((expr, cond)) + # If there is one condition, put the generic case first. Otherwise, + # doing so may lead to longer Piecewise formulas + if len(pairs) == 1: + pairs = [(heurisch(f, x, rewrite, hints, mappings, retries, + degree_offset, unnecessary_permutations, + _try_heurisch), + generic), + (pairs[0][0], True)] + else: + pairs.append((heurisch(f, x, rewrite, hints, mappings, retries, + degree_offset, unnecessary_permutations, + _try_heurisch), + True)) + return Piecewise(*pairs) + +class BesselTable: + """ + Derivatives of Bessel functions of orders n and n-1 + in terms of each other. + + See the docstring of DiffCache. + """ + + def __init__(self): + self.table = {} + self.n = Dummy('n') + self.z = Dummy('z') + self._create_table() + + def _create_table(t): + table, n, z = t.table, t.n, t.z + for f in (besselj, bessely, hankel1, hankel2): + table[f] = (f(n-1, z) - n*f(n, z)/z, + (n-1)*f(n-1, z)/z - f(n, z)) + + f = besseli + table[f] = (f(n-1, z) - n*f(n, z)/z, + (n-1)*f(n-1, z)/z + f(n, z)) + f = besselk + table[f] = (-f(n-1, z) - n*f(n, z)/z, + (n-1)*f(n-1, z)/z - f(n, z)) + + for f in (jn, yn): + table[f] = (f(n-1, z) - (n+1)*f(n, z)/z, + (n-1)*f(n-1, z)/z - f(n, z)) + + def diffs(t, f, n, z): + if f in t.table: + diff0, diff1 = t.table[f] + repl = [(t.n, n), (t.z, z)] + return (diff0.subs(repl), diff1.subs(repl)) + + def has(t, f): + return f in t.table + +_bessel_table = None + +class DiffCache: + """ + Store for derivatives of expressions. + + Explanation + =========== + + The standard form of the derivative of a Bessel function of order n + contains two Bessel functions of orders n-1 and n+1, respectively. + Such forms cannot be used in parallel Risch algorithm, because + there is a linear recurrence relation between the three functions + while the algorithm expects that functions and derivatives are + represented in terms of algebraically independent transcendentals. + + The solution is to take two of the functions, e.g., those of orders + n and n-1, and to express the derivatives in terms of the pair. + To guarantee that the proper form is used the two derivatives are + cached as soon as one is encountered. + + Derivatives of other functions are also cached at no extra cost. + All derivatives are with respect to the same variable `x`. + """ + + def __init__(self, x): + self.cache = {} + self.x = x + + global _bessel_table + if not _bessel_table: + _bessel_table = BesselTable() + + def get_diff(self, f): + cache = self.cache + + if f in cache: + pass + elif (not hasattr(f, 'func') or + not _bessel_table.has(f.func)): + cache[f] = cancel(f.diff(self.x)) + else: + n, z = f.args + d0, d1 = _bessel_table.diffs(f.func, n, z) + dz = self.get_diff(z) + cache[f] = d0*dz + cache[f.func(n-1, z)] = d1*dz + + return cache[f] + +def heurisch(f, x, rewrite=False, hints=None, mappings=None, retries=3, + degree_offset=0, unnecessary_permutations=None, + _try_heurisch=None): + """ + Compute indefinite integral using heuristic Risch algorithm. + + Explanation + =========== + + This is a heuristic approach to indefinite integration in finite + terms using the extended heuristic (parallel) Risch algorithm, based + on Manuel Bronstein's "Poor Man's Integrator". + + The algorithm supports various classes of functions including + transcendental elementary or special functions like Airy, + Bessel, Whittaker and Lambert. + + Note that this algorithm is not a decision procedure. If it isn't + able to compute the antiderivative for a given function, then this is + not a proof that such a functions does not exist. One should use + recursive Risch algorithm in such case. It's an open question if + this algorithm can be made a full decision procedure. + + This is an internal integrator procedure. You should use top level + 'integrate' function in most cases, as this procedure needs some + preprocessing steps and otherwise may fail. + + Specification + ============= + + heurisch(f, x, rewrite=False, hints=None) + + where + f : expression + x : symbol + + rewrite -> force rewrite 'f' in terms of 'tan' and 'tanh' + hints -> a list of functions that may appear in anti-derivate + + - hints = None --> no suggestions at all + - hints = [ ] --> try to figure out + - hints = [f1, ..., fn] --> we know better + + Examples + ======== + + >>> from sympy import tan + >>> from sympy.integrals.heurisch import heurisch + >>> from sympy.abc import x, y + + >>> heurisch(y*tan(x), x) + y*log(tan(x)**2 + 1)/2 + + See Manuel Bronstein's "Poor Man's Integrator": + + References + ========== + + .. [1] https://www-sop.inria.fr/cafe/Manuel.Bronstein/pmint/index.html + + For more information on the implemented algorithm refer to: + + .. [2] K. Geddes, L. Stefanus, On the Risch-Norman Integration + Method and its Implementation in Maple, Proceedings of + ISSAC'89, ACM Press, 212-217. + + .. [3] J. H. Davenport, On the Parallel Risch Algorithm (I), + Proceedings of EUROCAM'82, LNCS 144, Springer, 144-157. + + .. [4] J. H. Davenport, On the Parallel Risch Algorithm (III): + Use of Tangents, SIGSAM Bulletin 16 (1982), 3-6. + + .. [5] J. H. Davenport, B. M. Trager, On the Parallel Risch + Algorithm (II), ACM Transactions on Mathematical + Software 11 (1985), 356-362. + + See Also + ======== + + sympy.integrals.integrals.Integral.doit + sympy.integrals.integrals.Integral + sympy.integrals.heurisch.components + """ + f = sympify(f) + + # There are some functions that Heurisch cannot currently handle, + # so do not even try. + # Set _try_heurisch=True to skip this check + if _try_heurisch is not True: + if f.has(Abs, re, im, sign, Heaviside, DiracDelta, floor, ceiling, arg): + return + + if not f.has_free(x): + return f*x + + if not f.is_Add: + indep, f = f.as_independent(x) + else: + indep = S.One + + rewritables = { + (sin, cos, cot): tan, + (sinh, cosh, coth): tanh, + } + + if rewrite: + for candidates, rule in rewritables.items(): + f = f.rewrite(candidates, rule) + else: + for candidates in rewritables.keys(): + if f.has(*candidates): + break + else: + rewrite = True + + terms = components(f, x) + dcache = DiffCache(x) + + if hints is not None: + if not hints: + a = Wild('a', exclude=[x]) + b = Wild('b', exclude=[x]) + c = Wild('c', exclude=[x]) + + for g in set(terms): # using copy of terms + if g.is_Function: + if isinstance(g, li): + M = g.args[0].match(a*x**b) + + if M is not None: + terms.add( x*(li(M[a]*x**M[b]) - (M[a]*x**M[b])**(-1/M[b])*Ei((M[b]+1)*log(M[a]*x**M[b])/M[b])) ) + #terms.add( x*(li(M[a]*x**M[b]) - (x**M[b])**(-1/M[b])*Ei((M[b]+1)*log(M[a]*x**M[b])/M[b])) ) + #terms.add( x*(li(M[a]*x**M[b]) - x*Ei((M[b]+1)*log(M[a]*x**M[b])/M[b])) ) + #terms.add( li(M[a]*x**M[b]) - Ei((M[b]+1)*log(M[a]*x**M[b])/M[b]) ) + + elif isinstance(g, exp): + M = g.args[0].match(a*x**2) + + if M is not None: + if M[a].is_positive: + terms.add(erfi(sqrt(M[a])*x)) + else: # M[a].is_negative or unknown + terms.add(erf(sqrt(-M[a])*x)) + + M = g.args[0].match(a*x**2 + b*x + c) + + if M is not None: + if M[a].is_positive: + terms.add(sqrt(pi/4*(-M[a]))*exp(M[c] - M[b]**2/(4*M[a]))* + erfi(sqrt(M[a])*x + M[b]/(2*sqrt(M[a])))) + elif M[a].is_negative: + terms.add(sqrt(pi/4*(-M[a]))*exp(M[c] - M[b]**2/(4*M[a]))* + erf(sqrt(-M[a])*x - M[b]/(2*sqrt(-M[a])))) + + M = g.args[0].match(a*log(x)**2) + + if M is not None: + if M[a].is_positive: + terms.add(erfi(sqrt(M[a])*log(x) + 1/(2*sqrt(M[a])))) + if M[a].is_negative: + terms.add(erf(sqrt(-M[a])*log(x) - 1/(2*sqrt(-M[a])))) + + elif g.is_Pow: + if g.exp.is_Rational and g.exp.q == 2: + M = g.base.match(a*x**2 + b) + + if M is not None and M[b].is_positive: + if M[a].is_positive: + terms.add(asinh(sqrt(M[a]/M[b])*x)) + elif M[a].is_negative: + terms.add(asin(sqrt(-M[a]/M[b])*x)) + + M = g.base.match(a*x**2 - b) + + if M is not None and M[b].is_positive: + if M[a].is_positive: + dF = 1/sqrt(M[a]*x**2 - M[b]) + F = log(2*sqrt(M[a])*sqrt(M[a]*x**2 - M[b]) + 2*M[a]*x)/sqrt(M[a]) + dcache.cache[F] = dF # hack: F.diff(x) doesn't automatically simplify to f + terms.add(F) + elif M[a].is_negative: + terms.add(-M[b]/2*sqrt(-M[a])* + atan(sqrt(-M[a])*x/sqrt(M[a]*x**2 - M[b]))) + + else: + terms |= set(hints) + + for g in set(terms): # using copy of terms + terms |= components(dcache.get_diff(g), x) + + # XXX: The commented line below makes heurisch more deterministic wrt + # PYTHONHASHSEED and the iteration order of sets. There are other places + # where sets are iterated over but this one is possibly the most important. + # Theoretically the order here should not matter but different orderings + # can expose potential bugs in the different code paths so potentially it + # is better to keep the non-determinism. + # + # terms = list(ordered(terms)) + + # TODO: caching is significant factor for why permutations work at all. Change this. + V = _symbols('x', len(terms)) + + + # sort mapping expressions from largest to smallest (last is always x). + mapping = list(reversed(list(zip(*ordered( # + [(a[0].as_independent(x)[1], a) for a in zip(terms, V)])))[1])) # + rev_mapping = {v: k for k, v in mapping} # + if mappings is None: # + # optimizing the number of permutations of mapping # + assert mapping[-1][0] == x # if not, find it and correct this comment + unnecessary_permutations = [mapping.pop(-1)] + # permute types of objects + types = defaultdict(list) + for i in mapping: + e, _ = i + types[type(e)].append(i) + mapping = [types[i] for i in types] + def _iter_mappings(): + for i in permutations(mapping): + # make the expression of a given type be ordered + yield [j for i in i for j in ordered(i)] + mappings = _iter_mappings() + else: + unnecessary_permutations = unnecessary_permutations or [] + + def _substitute(expr): + return expr.subs(mapping) + + for mapping in mappings: + mapping = list(mapping) + mapping = mapping + unnecessary_permutations + diffs = [ _substitute(dcache.get_diff(g)) for g in terms ] + denoms = [ g.as_numer_denom()[1] for g in diffs ] + if all(h.is_polynomial(*V) for h in denoms) and _substitute(f).is_rational_function(*V): + denom = reduce(lambda p, q: lcm(p, q, *V), denoms) + break + else: + if not rewrite: + result = heurisch(f, x, rewrite=True, hints=hints, + unnecessary_permutations=unnecessary_permutations) + + if result is not None: + return indep*result + return None + + numers = [ cancel(denom*g) for g in diffs ] + def _derivation(h): + return Add(*[ d * h.diff(v) for d, v in zip(numers, V) ]) + + def _deflation(p): + for y in V: + if not p.has(y): + continue + + if _derivation(p) is not S.Zero: + c, q = p.as_poly(y).primitive() + return _deflation(c)*gcd(q, q.diff(y)).as_expr() + + return p + + def _splitter(p): + for y in V: + if not p.has(y): + continue + + if _derivation(y) is not S.Zero: + c, q = p.as_poly(y).primitive() + + q = q.as_expr() + + h = gcd(q, _derivation(q), y) + s = quo(h, gcd(q, q.diff(y), y), y) + + c_split = _splitter(c) + + if s.as_poly(y).degree() == 0: + return (c_split[0], q * c_split[1]) + + q_split = _splitter(cancel(q / s)) + + return (c_split[0]*q_split[0]*s, c_split[1]*q_split[1]) + + return (S.One, p) + + special = {} + + for term in terms: + if term.is_Function: + if isinstance(term, tan): + special[1 + _substitute(term)**2] = False + elif isinstance(term, tanh): + special[1 + _substitute(term)] = False + special[1 - _substitute(term)] = False + elif isinstance(term, LambertW): + special[_substitute(term)] = True + + F = _substitute(f) + + P, Q = F.as_numer_denom() + + u_split = _splitter(denom) + v_split = _splitter(Q) + + polys = set(list(v_split) + [ u_split[0] ] + list(special.keys())) + + s = u_split[0] * Mul(*[ k for k, v in special.items() if v ]) + polified = [ p.as_poly(*V) for p in [s, P, Q] ] + + if None in polified: + return None + + #--- definitions for _integrate + a, b, c = [ p.total_degree() for p in polified ] + + poly_denom = (s * v_split[0] * _deflation(v_split[1])).as_expr() + + def _exponent(g): + if g.is_Pow: + if g.exp.is_Rational and g.exp.q != 1: + if g.exp.p > 0: + return g.exp.p + g.exp.q - 1 + else: + return abs(g.exp.p + g.exp.q) + else: + return 1 + elif not g.is_Atom and g.args: + return max(_exponent(h) for h in g.args) + else: + return 1 + + A, B = _exponent(f), a + max(b, c) + + if A > 1 and B > 1: + monoms = tuple(ordered(itermonomials(V, A + B - 1 + degree_offset))) + else: + monoms = tuple(ordered(itermonomials(V, A + B + degree_offset))) + + poly_coeffs = _symbols('A', len(monoms)) + + poly_part = Add(*[ poly_coeffs[i]*monomial + for i, monomial in enumerate(monoms) ]) + + reducibles = set() + + for poly in ordered(polys): + coeff, factors = factor_list(poly, *V) + reducibles.add(coeff) + reducibles.update(fact for fact, mul in factors) + + def _integrate(field=None): + atans = set() + pairs = set() + + if field == 'Q': + irreducibles = set(reducibles) + else: + setV = set(V) + irreducibles = set() + for poly in ordered(reducibles): + zV = setV & set(iterfreeargs(poly)) + for z in ordered(zV): + s = set(root_factors(poly, z, filter=field)) + irreducibles |= s + break + + log_part, atan_part = [], [] + + for poly in ordered(irreducibles): + m = collect(poly, I, evaluate=False) + y = m.get(I, S.Zero) + if y: + x = m.get(S.One, S.Zero) + if x.has(I) or y.has(I): + continue # nontrivial x + I*y + pairs.add((x, y)) + irreducibles.remove(poly) + + while pairs: + x, y = pairs.pop() + if (x, -y) in pairs: + pairs.remove((x, -y)) + # Choosing b with no minus sign + if y.could_extract_minus_sign(): + y = -y + irreducibles.add(x*x + y*y) + atans.add(atan(x/y)) + else: + irreducibles.add(x + I*y) + + + B = _symbols('B', len(irreducibles)) + C = _symbols('C', len(atans)) + + # Note: the ordering matters here + for poly, b in reversed(list(zip(ordered(irreducibles), B))): + if poly.has(*V): + poly_coeffs.append(b) + log_part.append(b * log(poly)) + + for poly, c in reversed(list(zip(ordered(atans), C))): + if poly.has(*V): + poly_coeffs.append(c) + atan_part.append(c * poly) + + # TODO: Currently it's better to use symbolic expressions here instead + # of rational functions, because it's simpler and FracElement doesn't + # give big speed improvement yet. This is because cancellation is slow + # due to slow polynomial GCD algorithms. If this gets improved then + # revise this code. + candidate = poly_part/poly_denom + Add(*log_part) + Add(*atan_part) + h = F - _derivation(candidate) / denom + raw_numer = h.as_numer_denom()[0] + + # Rewrite raw_numer as a polynomial in K[coeffs][V] where K is a field + # that we have to determine. We can't use simply atoms() because log(3), + # sqrt(y) and similar expressions can appear, leading to non-trivial + # domains. + syms = set(poly_coeffs) | set(V) + non_syms = set() + + def find_non_syms(expr): + if expr.is_Integer or expr.is_Rational: + pass # ignore trivial numbers + elif expr in syms: + pass # ignore variables + elif not expr.has_free(*syms): + non_syms.add(expr) + elif expr.is_Add or expr.is_Mul or expr.is_Pow: + list(map(find_non_syms, expr.args)) + else: + # TODO: Non-polynomial expression. This should have been + # filtered out at an earlier stage. + raise PolynomialError + + try: + find_non_syms(raw_numer) + except PolynomialError: + return None + else: + ground, _ = construct_domain(non_syms, field=True) + + coeff_ring = PolyRing(poly_coeffs, ground) + ring = PolyRing(V, coeff_ring) + try: + numer = ring.from_expr(raw_numer) + except ValueError: + raise PolynomialError + solution = solve_lin_sys(numer.coeffs(), coeff_ring, _raw=False) + + if solution is None: + return None + else: + return candidate.xreplace(solution).xreplace( + dict(zip(poly_coeffs, [S.Zero]*len(poly_coeffs)))) + + if all(isinstance(_, Symbol) for _ in V): + more_free = F.free_symbols - set(V) + else: + Fd = F.as_dummy() + more_free = Fd.xreplace(dict(zip(V, (Dummy() for _ in V))) + ).free_symbols & Fd.free_symbols + if not more_free: + # all free generators are identified in V + solution = _integrate('Q') + + if solution is None: + solution = _integrate() + else: + solution = _integrate() + + if solution is not None: + antideriv = solution.subs(rev_mapping) + antideriv = cancel(antideriv).expand() + + if antideriv.is_Add: + antideriv = antideriv.as_independent(x)[1] + + return indep*antideriv + else: + if retries >= 0: + result = heurisch(f, x, mappings=mappings, rewrite=rewrite, hints=hints, retries=retries - 1, unnecessary_permutations=unnecessary_permutations) + + if result is not None: + return indep*result + + return None diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/integrals.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/integrals.py new file mode 100644 index 0000000000000000000000000000000000000000..b9ed4a22802acc455f5162e109fc575223c97338 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/integrals.py @@ -0,0 +1,1640 @@ +from __future__ import annotations + +from sympy.concrete.expr_with_limits import AddWithLimits +from sympy.core.add import Add +from sympy.core.basic import Basic +from sympy.core.containers import Tuple +from sympy.core.expr import Expr +from sympy.core.exprtools import factor_terms +from sympy.core.function import diff +from sympy.core.logic import fuzzy_bool +from sympy.core.mul import Mul +from sympy.core.numbers import oo, pi +from sympy.core.relational import Ne +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, Symbol, Wild) +from sympy.core.sympify import sympify +from sympy.functions import Piecewise, sqrt, piecewise_fold, tan, cot, atan +from sympy.functions.elementary.exponential import log +from sympy.functions.elementary.integers import floor +from sympy.functions.elementary.complexes import Abs, sign +from sympy.functions.elementary.miscellaneous import Min, Max +from sympy.functions.special.singularity_functions import Heaviside +from .rationaltools import ratint +from sympy.matrices import MatrixBase +from sympy.polys import Poly, PolynomialError +from sympy.series.formal import FormalPowerSeries +from sympy.series.limits import limit +from sympy.series.order import Order +from sympy.tensor.functions import shape +from sympy.utilities.exceptions import sympy_deprecation_warning +from sympy.utilities.iterables import is_sequence +from sympy.utilities.misc import filldedent + + +class Integral(AddWithLimits): + """Represents unevaluated integral.""" + + __slots__ = () + + args: tuple[Expr, Tuple] # type: ignore + + def __new__(cls, function, *symbols, **assumptions) -> Integral: + """Create an unevaluated integral. + + Explanation + =========== + + Arguments are an integrand followed by one or more limits. + + If no limits are given and there is only one free symbol in the + expression, that symbol will be used, otherwise an error will be + raised. + + >>> from sympy import Integral + >>> from sympy.abc import x, y + >>> Integral(x) + Integral(x, x) + >>> Integral(y) + Integral(y, y) + + When limits are provided, they are interpreted as follows (using + ``x`` as though it were the variable of integration): + + (x,) or x - indefinite integral + (x, a) - "evaluate at" integral is an abstract antiderivative + (x, a, b) - definite integral + + The ``as_dummy`` method can be used to see which symbols cannot be + targeted by subs: those with a prepended underscore cannot be + changed with ``subs``. (Also, the integration variables themselves -- + the first element of a limit -- can never be changed by subs.) + + >>> i = Integral(x, x) + >>> at = Integral(x, (x, x)) + >>> i.as_dummy() + Integral(x, x) + >>> at.as_dummy() + Integral(_0, (_0, x)) + + """ + + #This will help other classes define their own definitions + #of behaviour with Integral. + if hasattr(function, '_eval_Integral'): + return function._eval_Integral(*symbols, **assumptions) + + if isinstance(function, Poly): + sympy_deprecation_warning( + """ + integrate(Poly) and Integral(Poly) are deprecated. Instead, + use the Poly.integrate() method, or convert the Poly to an + Expr first with the Poly.as_expr() method. + """, + deprecated_since_version="1.6", + active_deprecations_target="deprecated-integrate-poly") + + obj = AddWithLimits.__new__(cls, function, *symbols, **assumptions) + return obj + + def __getnewargs__(self): + return (self.function,) + tuple([tuple(xab) for xab in self.limits]) + + @property + def free_symbols(self): + """ + This method returns the symbols that will exist when the + integral is evaluated. This is useful if one is trying to + determine whether an integral depends on a certain + symbol or not. + + Examples + ======== + + >>> from sympy import Integral + >>> from sympy.abc import x, y + >>> Integral(x, (x, y, 1)).free_symbols + {y} + + See Also + ======== + + sympy.concrete.expr_with_limits.ExprWithLimits.function + sympy.concrete.expr_with_limits.ExprWithLimits.limits + sympy.concrete.expr_with_limits.ExprWithLimits.variables + """ + return super().free_symbols + + def _eval_is_zero(self): + # This is a very naive and quick test, not intended to do the integral to + # answer whether it is zero or not, e.g. Integral(sin(x), (x, 0, 2*pi)) + # is zero but this routine should return None for that case. But, like + # Mul, there are trivial situations for which the integral will be + # zero so we check for those. + if self.function.is_zero: + return True + got_none = False + for l in self.limits: + if len(l) == 3: + z = (l[1] == l[2]) or (l[1] - l[2]).is_zero + if z: + return True + elif z is None: + got_none = True + free = self.function.free_symbols + for xab in self.limits: + if len(xab) == 1: + free.add(xab[0]) + continue + if len(xab) == 2 and xab[0] not in free: + if xab[1].is_zero: + return True + elif xab[1].is_zero is None: + got_none = True + # take integration symbol out of free since it will be replaced + # with the free symbols in the limits + free.discard(xab[0]) + # add in the new symbols + for i in xab[1:]: + free.update(i.free_symbols) + if self.function.is_zero is False and got_none is False: + return False + + def transform(self, x, u): + r""" + Performs a change of variables from `x` to `u` using the relationship + given by `x` and `u` which will define the transformations `f` and `F` + (which are inverses of each other) as follows: + + 1) If `x` is a Symbol (which is a variable of integration) then `u` + will be interpreted as some function, f(u), with inverse F(u). + This, in effect, just makes the substitution of x with f(x). + + 2) If `u` is a Symbol then `x` will be interpreted as some function, + F(x), with inverse f(u). This is commonly referred to as + u-substitution. + + Once f and F have been identified, the transformation is made as + follows: + + .. math:: \int_a^b x \mathrm{d}x \rightarrow \int_{F(a)}^{F(b)} f(x) + \frac{\mathrm{d}}{\mathrm{d}x} + + where `F(x)` is the inverse of `f(x)` and the limits and integrand have + been corrected so as to retain the same value after integration. + + Notes + ===== + + The mappings, F(x) or f(u), must lead to a unique integral. Linear + or rational linear expression, ``2*x``, ``1/x`` and ``sqrt(x)``, will + always work; quadratic expressions like ``x**2 - 1`` are acceptable + as long as the resulting integrand does not depend on the sign of + the solutions (see examples). + + The integral will be returned unchanged if ``x`` is not a variable of + integration. + + ``x`` must be (or contain) only one of of the integration variables. If + ``u`` has more than one free symbol then it should be sent as a tuple + (``u``, ``uvar``) where ``uvar`` identifies which variable is replacing + the integration variable. + XXX can it contain another integration variable? + + Examples + ======== + + >>> from sympy.abc import a, x, u + >>> from sympy import Integral, cos, sqrt + + >>> i = Integral(x*cos(x**2 - 1), (x, 0, 1)) + + transform can change the variable of integration + + >>> i.transform(x, u) + Integral(u*cos(u**2 - 1), (u, 0, 1)) + + transform can perform u-substitution as long as a unique + integrand is obtained: + + >>> ui = i.transform(x**2 - 1, u) + >>> ui + Integral(cos(u)/2, (u, -1, 0)) + + This attempt fails because x = +/-sqrt(u + 1) and the + sign does not cancel out of the integrand: + + >>> Integral(cos(x**2 - 1), (x, 0, 1)).transform(x**2 - 1, u) + Traceback (most recent call last): + ... + ValueError: + The mapping between F(x) and f(u) did not give a unique integrand. + + transform can do a substitution. Here, the previous + result is transformed back into the original expression + using "u-substitution": + + >>> ui.transform(sqrt(u + 1), x) == i + True + + We can accomplish the same with a regular substitution: + + >>> ui.transform(u, x**2 - 1) == i + True + + If the `x` does not contain a symbol of integration then + the integral will be returned unchanged. Integral `i` does + not have an integration variable `a` so no change is made: + + >>> i.transform(a, x) == i + True + + When `u` has more than one free symbol the symbol that is + replacing `x` must be identified by passing `u` as a tuple: + + >>> Integral(x, (x, 0, 1)).transform(x, (u + a, u)) + Integral(a + u, (u, -a, 1 - a)) + >>> Integral(x, (x, 0, 1)).transform(x, (u + a, a)) + Integral(a + u, (a, -u, 1 - u)) + + See Also + ======== + + sympy.concrete.expr_with_limits.ExprWithLimits.variables : Lists the integration variables + as_dummy : Replace integration variables with dummy ones + """ + d = Dummy('d') + + xfree = x.free_symbols.intersection(self.variables) + if len(xfree) > 1: + raise ValueError( + 'F(x) can only contain one of: %s' % self.variables) + xvar = xfree.pop() if xfree else d + + if xvar not in self.variables: + return self + + u = sympify(u) + if isinstance(u, Expr): + ufree = u.free_symbols + if len(ufree) == 0: + raise ValueError(filldedent(''' + f(u) cannot be a constant''')) + if len(ufree) > 1: + raise ValueError(filldedent(''' + When f(u) has more than one free symbol, the one replacing x + must be identified: pass f(u) as (f(u), u)''')) + uvar = ufree.pop() + else: + u, uvar = u + if uvar not in u.free_symbols: + raise ValueError(filldedent(''' + Expecting a tuple (expr, symbol) where symbol identified + a free symbol in expr, but symbol is not in expr's free + symbols.''')) + if not isinstance(uvar, Symbol): + # This probably never evaluates to True + raise ValueError(filldedent(''' + Expecting a tuple (expr, symbol) but didn't get + a symbol; got %s''' % uvar)) + + if x.is_Symbol and u.is_Symbol: + return self.xreplace({x: u}) + + if not x.is_Symbol and not u.is_Symbol: + raise ValueError('either x or u must be a symbol') + + if uvar == xvar: + return self.transform(x, (u.subs(uvar, d), d)).xreplace({d: uvar}) + + if uvar in self.limits: + raise ValueError(filldedent(''' + u must contain the same variable as in x + or a variable that is not already an integration variable''')) + + from sympy.solvers.solvers import solve + if not x.is_Symbol: + F = [x.subs(xvar, d)] + soln = solve(u - x, xvar, check=False) + if not soln: + raise ValueError('no solution for solve(F(x) - f(u), x)') + f = [fi.subs(uvar, d) for fi in soln] + else: + f = [u.subs(uvar, d)] + from sympy.simplify.simplify import posify + pdiff, reps = posify(u - x) + puvar = uvar.subs([(v, k) for k, v in reps.items()]) + soln = [s.subs(reps) for s in solve(pdiff, puvar)] + if not soln: + raise ValueError('no solution for solve(F(x) - f(u), u)') + F = [fi.subs(xvar, d) for fi in soln] + + newfuncs = {(self.function.subs(xvar, fi)*fi.diff(d) + ).subs(d, uvar) for fi in f} + if len(newfuncs) > 1: + raise ValueError(filldedent(''' + The mapping between F(x) and f(u) did not give + a unique integrand.''')) + newfunc = newfuncs.pop() + + def _calc_limit_1(F, a, b): + """ + replace d with a, using subs if possible, otherwise limit + where sign of b is considered + """ + wok = F.subs(d, a) + if wok is S.NaN or wok.is_finite is False and a.is_finite: + return limit(sign(b)*F, d, a) + return wok + + def _calc_limit(a, b): + """ + replace d with a, using subs if possible, otherwise limit + where sign of b is considered + """ + avals = list({_calc_limit_1(Fi, a, b) for Fi in F}) + if len(avals) > 1: + raise ValueError(filldedent(''' + The mapping between F(x) and f(u) did not + give a unique limit.''')) + return avals[0] + + newlimits = [] + for xab in self.limits: + sym = xab[0] + if sym == xvar: + if len(xab) == 3: + a, b = xab[1:] + a, b = _calc_limit(a, b), _calc_limit(b, a) + if fuzzy_bool(a - b > 0): + a, b = b, a + newfunc = -newfunc + newlimits.append((uvar, a, b)) + elif len(xab) == 2: + a = _calc_limit(xab[1], 1) + newlimits.append((uvar, a)) + else: + newlimits.append(uvar) + else: + newlimits.append(xab) + + return self.func(newfunc, *newlimits) + + def doit(self, **hints): + """ + Perform the integration using any hints given. + + Examples + ======== + + >>> from sympy import Piecewise, S + >>> from sympy.abc import x, t + >>> p = x**2 + Piecewise((0, x/t < 0), (1, True)) + >>> p.integrate((t, S(4)/5, 1), (x, -1, 1)) + 1/3 + + See Also + ======== + + sympy.integrals.trigonometry.trigintegrate + sympy.integrals.heurisch.heurisch + sympy.integrals.rationaltools.ratint + as_sum : Approximate the integral using a sum + """ + if not hints.get('integrals', True): + return self + + deep = hints.get('deep', True) + meijerg = hints.get('meijerg', None) + conds = hints.get('conds', 'piecewise') + risch = hints.get('risch', None) + heurisch = hints.get('heurisch', None) + manual = hints.get('manual', None) + if len(list(filter(None, (manual, meijerg, risch, heurisch)))) > 1: + raise ValueError("At most one of manual, meijerg, risch, heurisch can be True") + elif manual: + meijerg = risch = heurisch = False + elif meijerg: + manual = risch = heurisch = False + elif risch: + manual = meijerg = heurisch = False + elif heurisch: + manual = meijerg = risch = False + eval_kwargs = {"meijerg": meijerg, "risch": risch, "manual": manual, "heurisch": heurisch, + "conds": conds} + + if conds not in ('separate', 'piecewise', 'none'): + raise ValueError('conds must be one of "separate", "piecewise", ' + '"none", got: %s' % conds) + + if risch and any(len(xab) > 1 for xab in self.limits): + raise ValueError('risch=True is only allowed for indefinite integrals.') + + # check for the trivial zero + if self.is_zero: + return S.Zero + + # hacks to handle integrals of + # nested summations + from sympy.concrete.summations import Sum + if isinstance(self.function, Sum): + if any(v in self.function.limits[0] for v in self.variables): + raise ValueError('Limit of the sum cannot be an integration variable.') + if any(l.is_infinite for l in self.function.limits[0][1:]): + return self + _i = self + _sum = self.function + return _sum.func(_i.func(_sum.function, *_i.limits).doit(), *_sum.limits).doit() + + # now compute and check the function + function = self.function + + # hack to use a consistent Heaviside(x, 1/2) + function = function.replace( + lambda x: isinstance(x, Heaviside) and x.args[1]*2 != 1, + lambda x: Heaviside(x.args[0])) + + if deep: + function = function.doit(**hints) + if function.is_zero: + return S.Zero + + # hacks to handle special cases + if isinstance(function, MatrixBase): + return function.applyfunc( + lambda f: self.func(f, *self.limits).doit(**hints)) + + if isinstance(function, FormalPowerSeries): + if len(self.limits) > 1: + raise NotImplementedError + xab = self.limits[0] + if len(xab) > 1: + return function.integrate(xab, **eval_kwargs) + else: + return function.integrate(xab[0], **eval_kwargs) + + # There is no trivial answer and special handling + # is done so continue + + # first make sure any definite limits have integration + # variables with matching assumptions + reps = {} + for xab in self.limits: + if len(xab) != 3: + # it makes sense to just make + # all x real but in practice with the + # current state of integration...this + # doesn't work out well + # x = xab[0] + # if x not in reps and not x.is_real: + # reps[x] = Dummy(real=True) + continue + x, a, b = xab + l = (a, b) + if all(i.is_nonnegative for i in l) and not x.is_nonnegative: + d = Dummy(positive=True) + elif all(i.is_nonpositive for i in l) and not x.is_nonpositive: + d = Dummy(negative=True) + elif all(i.is_real for i in l) and not x.is_real: + d = Dummy(real=True) + else: + d = None + if d: + reps[x] = d + if reps: + undo = {v: k for k, v in reps.items()} + did = self.xreplace(reps).doit(**hints) + if isinstance(did, tuple): # when separate=True + did = tuple([i.xreplace(undo) for i in did]) + else: + did = did.xreplace(undo) + return did + + # continue with existing assumptions + undone_limits = [] + # ulj = free symbols of any undone limits' upper and lower limits + ulj = set() + for xab in self.limits: + # compute uli, the free symbols in the + # Upper and Lower limits of limit I + if len(xab) == 1: + uli = set(xab[:1]) + elif len(xab) == 2: + uli = xab[1].free_symbols + elif len(xab) == 3: + uli = xab[1].free_symbols.union(xab[2].free_symbols) + # this integral can be done as long as there is no blocking + # limit that has been undone. An undone limit is blocking if + # it contains an integration variable that is in this limit's + # upper or lower free symbols or vice versa + if xab[0] in ulj or any(v[0] in uli for v in undone_limits): + undone_limits.append(xab) + ulj.update(uli) + function = self.func(*([function] + [xab])) + factored_function = function.factor() + if not isinstance(factored_function, Integral): + function = factored_function + continue + + if function.has(Abs, sign) and ( + (len(xab) < 3 and all(x.is_extended_real for x in xab)) or + (len(xab) == 3 and all(x.is_extended_real and not x.is_infinite for + x in xab[1:]))): + # some improper integrals are better off with Abs + xr = Dummy("xr", real=True) + function = (function.xreplace({xab[0]: xr}) + .rewrite(Piecewise).xreplace({xr: xab[0]})) + elif function.has(Min, Max): + function = function.rewrite(Piecewise) + if (function.has(Piecewise) and + not isinstance(function, Piecewise)): + function = piecewise_fold(function) + if isinstance(function, Piecewise): + if len(xab) == 1: + antideriv = function._eval_integral(xab[0], + **eval_kwargs) + else: + antideriv = self._eval_integral( + function, xab[0], **eval_kwargs) + else: + # There are a number of tradeoffs in using the + # Meijer G method. It can sometimes be a lot faster + # than other methods, and sometimes slower. And + # there are certain types of integrals for which it + # is more likely to work than others. These + # heuristics are incorporated in deciding what + # integration methods to try, in what order. See the + # integrate() docstring for details. + def try_meijerg(function, xab): + ret = None + if len(xab) == 3 and meijerg is not False: + x, a, b = xab + try: + res = meijerint_definite(function, x, a, b) + except NotImplementedError: + _debug('NotImplementedError ' + 'from meijerint_definite') + res = None + if res is not None: + f, cond = res + if conds == 'piecewise': + u = self.func(function, (x, a, b)) + # if Piecewise modifies cond too + # much it may not be recognized by + # _condsimp pattern matching so just + # turn off all evaluation + return Piecewise((f, cond), (u, True), + evaluate=False) + elif conds == 'separate': + if len(self.limits) != 1: + raise ValueError(filldedent(''' + conds=separate not supported in + multiple integrals''')) + ret = f, cond + else: + ret = f + return ret + + meijerg1 = meijerg + if (meijerg is not False and + len(xab) == 3 and xab[1].is_extended_real and xab[2].is_extended_real + and not function.is_Poly and + (xab[1].has(oo, -oo) or xab[2].has(oo, -oo))): + ret = try_meijerg(function, xab) + if ret is not None: + function = ret + continue + meijerg1 = False + # If the special meijerg code did not succeed in + # finding a definite integral, then the code using + # meijerint_indefinite will not either (it might + # find an antiderivative, but the answer is likely + # to be nonsensical). Thus if we are requested to + # only use Meijer G-function methods, we give up at + # this stage. Otherwise we just disable G-function + # methods. + if meijerg1 is False and meijerg is True: + antideriv = None + else: + antideriv = self._eval_integral( + function, xab[0], **eval_kwargs) + if antideriv is None and meijerg is True: + ret = try_meijerg(function, xab) + if ret is not None: + function = ret + continue + + final = hints.get('final', True) + # dotit may be iterated but floor terms making atan and acot + # continuous should only be added in the final round + if (final and not isinstance(antideriv, Integral) and + antideriv is not None): + for atan_term in antideriv.atoms(atan): + atan_arg = atan_term.args[0] + # Checking `atan_arg` to be linear combination of `tan` or `cot` + for tan_part in atan_arg.atoms(tan): + x1 = Dummy('x1') + tan_exp1 = atan_arg.subs(tan_part, x1) + # The coefficient of `tan` should be constant + coeff = tan_exp1.diff(x1) + if x1 not in coeff.free_symbols: + a = tan_part.args[0] + antideriv = antideriv.subs(atan_term, Add(atan_term, + sign(coeff)*pi*floor((a-pi/2)/pi))) + for cot_part in atan_arg.atoms(cot): + x1 = Dummy('x1') + cot_exp1 = atan_arg.subs(cot_part, x1) + # The coefficient of `cot` should be constant + coeff = cot_exp1.diff(x1) + if x1 not in coeff.free_symbols: + a = cot_part.args[0] + antideriv = antideriv.subs(atan_term, Add(atan_term, + sign(coeff)*pi*floor((a)/pi))) + + if antideriv is None: + undone_limits.append(xab) + function = self.func(*([function] + [xab])).factor() + factored_function = function.factor() + if not isinstance(factored_function, Integral): + function = factored_function + continue + else: + if len(xab) == 1: + function = antideriv + else: + if len(xab) == 3: + x, a, b = xab + elif len(xab) == 2: + x, b = xab + a = None + else: + raise NotImplementedError + + if deep: + if isinstance(a, Basic): + a = a.doit(**hints) + if isinstance(b, Basic): + b = b.doit(**hints) + + if antideriv.is_Poly: + gens = list(antideriv.gens) + gens.remove(x) + + antideriv = antideriv.as_expr() + + function = antideriv._eval_interval(x, a, b) + function = Poly(function, *gens) + else: + def is_indef_int(g, x): + return (isinstance(g, Integral) and + any(i == (x,) for i in g.limits)) + + def eval_factored(f, x, a, b): + # _eval_interval for integrals with + # (constant) factors + # a single indefinite integral is assumed + args = [] + for g in Mul.make_args(f): + if is_indef_int(g, x): + args.append(g._eval_interval(x, a, b)) + else: + args.append(g) + return Mul(*args) + + integrals, others, piecewises = [], [], [] + for f in Add.make_args(antideriv): + if any(is_indef_int(g, x) + for g in Mul.make_args(f)): + integrals.append(f) + elif any(isinstance(g, Piecewise) + for g in Mul.make_args(f)): + piecewises.append(piecewise_fold(f)) + else: + others.append(f) + uneval = Add(*[eval_factored(f, x, a, b) + for f in integrals]) + try: + evalued = Add(*others)._eval_interval(x, a, b) + evalued_pw = piecewise_fold(Add(*piecewises))._eval_interval(x, a, b) + function = uneval + evalued + evalued_pw + except NotImplementedError: + # This can happen if _eval_interval depends in a + # complicated way on limits that cannot be computed + undone_limits.append(xab) + function = self.func(*([function] + [xab])) + factored_function = function.factor() + if not isinstance(factored_function, Integral): + function = factored_function + return function + + def _eval_derivative(self, sym): + """Evaluate the derivative of the current Integral object by + differentiating under the integral sign [1], using the Fundamental + Theorem of Calculus [2] when possible. + + Explanation + =========== + + Whenever an Integral is encountered that is equivalent to zero or + has an integrand that is independent of the variable of integration + those integrals are performed. All others are returned as Integral + instances which can be resolved with doit() (provided they are integrable). + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Differentiation_under_the_integral_sign + .. [2] https://en.wikipedia.org/wiki/Fundamental_theorem_of_calculus + + Examples + ======== + + >>> from sympy import Integral + >>> from sympy.abc import x, y + >>> i = Integral(x + y, y, (y, 1, x)) + >>> i.diff(x) + Integral(x + y, (y, x)) + Integral(1, y, (y, 1, x)) + >>> i.doit().diff(x) == i.diff(x).doit() + True + >>> i.diff(y) + 0 + + The previous must be true since there is no y in the evaluated integral: + + >>> i.free_symbols + {x} + >>> i.doit() + 2*x**3/3 - x/2 - 1/6 + + """ + + # differentiate under the integral sign; we do not + # check for regularity conditions (TODO), see issue 4215 + + # get limits and the function + f, limits = self.function, list(self.limits) + + # the order matters if variables of integration appear in the limits + # so work our way in from the outside to the inside. + limit = limits.pop(-1) + if len(limit) == 3: + x, a, b = limit + elif len(limit) == 2: + x, b = limit + a = None + else: + a = b = None + x = limit[0] + + if limits: # f is the argument to an integral + f = self.func(f, *tuple(limits)) + + # assemble the pieces + def _do(f, ab): + dab_dsym = diff(ab, sym) + if not dab_dsym: + return S.Zero + if isinstance(f, Integral): + limits = [(x, x) if (len(l) == 1 and l[0] == x) else l + for l in f.limits] + f = self.func(f.function, *limits) + return f.subs(x, ab)*dab_dsym + + rv = S.Zero + if b is not None: + rv += _do(f, b) + if a is not None: + rv -= _do(f, a) + if len(limit) == 1 and sym == x: + # the dummy variable *is* also the real-world variable + arg = f + rv += arg + else: + # the dummy variable might match sym but it's + # only a dummy and the actual variable is determined + # by the limits, so mask off the variable of integration + # while differentiating + u = Dummy('u') + arg = f.subs(x, u).diff(sym).subs(u, x) + if arg: + rv += self.func(arg, (x, a, b)) + return rv + + def _eval_integral(self, f, x, meijerg=None, risch=None, manual=None, + heurisch=None, conds='piecewise',final=None): + """ + Calculate the anti-derivative to the function f(x). + + Explanation + =========== + + The following algorithms are applied (roughly in this order): + + 1. Simple heuristics (based on pattern matching and integral table): + + - most frequently used functions (e.g. polynomials, products of + trig functions) + + 2. Integration of rational functions: + + - A complete algorithm for integrating rational functions is + implemented (the Lazard-Rioboo-Trager algorithm). The algorithm + also uses the partial fraction decomposition algorithm + implemented in apart() as a preprocessor to make this process + faster. Note that the integral of a rational function is always + elementary, but in general, it may include a RootSum. + + 3. Full Risch algorithm: + + - The Risch algorithm is a complete decision + procedure for integrating elementary functions, which means that + given any elementary function, it will either compute an + elementary antiderivative, or else prove that none exists. + Currently, part of transcendental case is implemented, meaning + elementary integrals containing exponentials, logarithms, and + (soon!) trigonometric functions can be computed. The algebraic + case, e.g., functions containing roots, is much more difficult + and is not implemented yet. + + - If the routine fails (because the integrand is not elementary, or + because a case is not implemented yet), it continues on to the + next algorithms below. If the routine proves that the integrals + is nonelementary, it still moves on to the algorithms below, + because we might be able to find a closed-form solution in terms + of special functions. If risch=True, however, it will stop here. + + 4. The Meijer G-Function algorithm: + + - This algorithm works by first rewriting the integrand in terms of + very general Meijer G-Function (meijerg in SymPy), integrating + it, and then rewriting the result back, if possible. This + algorithm is particularly powerful for definite integrals (which + is actually part of a different method of Integral), since it can + compute closed-form solutions of definite integrals even when no + closed-form indefinite integral exists. But it also is capable + of computing many indefinite integrals as well. + + - Another advantage of this method is that it can use some results + about the Meijer G-Function to give a result in terms of a + Piecewise expression, which allows to express conditionally + convergent integrals. + + - Setting meijerg=True will cause integrate() to use only this + method. + + 5. The "manual integration" algorithm: + + - This algorithm tries to mimic how a person would find an + antiderivative by hand, for example by looking for a + substitution or applying integration by parts. This algorithm + does not handle as many integrands but can return results in a + more familiar form. + + - Sometimes this algorithm can evaluate parts of an integral; in + this case integrate() will try to evaluate the rest of the + integrand using the other methods here. + + - Setting manual=True will cause integrate() to use only this + method. + + 6. The Heuristic Risch algorithm: + + - This is a heuristic version of the Risch algorithm, meaning that + it is not deterministic. This is tried as a last resort because + it can be very slow. It is still used because not enough of the + full Risch algorithm is implemented, so that there are still some + integrals that can only be computed using this method. The goal + is to implement enough of the Risch and Meijer G-function methods + so that this can be deleted. + + Setting heurisch=True will cause integrate() to use only this + method. Set heurisch=False to not use it. + + """ + + from sympy.integrals.risch import risch_integrate, NonElementaryIntegral + from sympy.integrals.manualintegrate import manualintegrate + + if risch: + try: + return risch_integrate(f, x, conds=conds) + except NotImplementedError: + return None + + if manual: + try: + result = manualintegrate(f, x) + if result is not None and result.func != Integral: + return result + except (ValueError, PolynomialError): + pass + + eval_kwargs = {"meijerg": meijerg, "risch": risch, "manual": manual, + "heurisch": heurisch, "conds": conds} + + # if it is a poly(x) then let the polynomial integrate itself (fast) + # + # It is important to make this check first, otherwise the other code + # will return a SymPy expression instead of a Polynomial. + # + # see Polynomial for details. + if isinstance(f, Poly) and not (manual or meijerg or risch): + # Note: this is deprecated, but the deprecation warning is already + # issued in the Integral constructor. + return f.integrate(x) + + # Piecewise antiderivatives need to call special integrate. + if isinstance(f, Piecewise): + return f.piecewise_integrate(x, **eval_kwargs) + + # let's cut it short if `f` does not depend on `x`; if + # x is only a dummy, that will be handled below + if not f.has(x): + return f*x + + # try to convert to poly(x) and then integrate if successful (fast) + poly = f.as_poly(x) + if poly is not None and not (manual or meijerg or risch): + return poly.integrate().as_expr() + + if risch is not False: + try: + result, i = risch_integrate(f, x, separate_integral=True, + conds=conds) + except NotImplementedError: + pass + else: + if i: + # There was a nonelementary integral. Try integrating it. + + # if no part of the NonElementaryIntegral is integrated by + # the Risch algorithm, then use the original function to + # integrate, instead of re-written one + if result == 0: + return NonElementaryIntegral(f, x).doit(risch=False) + else: + return result + i.doit(risch=False) + else: + return result + + # since Integral(f=g1+g2+...) == Integral(g1) + Integral(g2) + ... + # we are going to handle Add terms separately, + # if `f` is not Add -- we only have one term + + # Note that in general, this is a bad idea, because Integral(g1) + + # Integral(g2) might not be computable, even if Integral(g1 + g2) is. + # For example, Integral(x**x + x**x*log(x)). But many heuristics only + # work term-wise. So we compute this step last, after trying + # risch_integrate. We also try risch_integrate again in this loop, + # because maybe the integral is a sum of an elementary part and a + # nonelementary part (like erf(x) + exp(x)). risch_integrate() is + # quite fast, so this is acceptable. + from sympy.simplify.fu import sincos_to_sum + parts = [] + args = Add.make_args(f) + for g in args: + coeff, g = g.as_independent(x) + + # g(x) = const + if g is S.One and not meijerg: + parts.append(coeff*x) + continue + + # g(x) = expr + O(x**n) + order_term = g.getO() + + if order_term is not None: + h = self._eval_integral(g.removeO(), x, **eval_kwargs) + + if h is not None: + h_order_expr = self._eval_integral(order_term.expr, x, **eval_kwargs) + + if h_order_expr is not None: + h_order_term = order_term.func( + h_order_expr, *order_term.variables) + parts.append(coeff*(h + h_order_term)) + continue + + # NOTE: if there is O(x**n) and we fail to integrate then + # there is no point in trying other methods because they + # will fail, too. + return None + + # c + # g(x) = (a*x+b) + if g.is_Pow and not g.exp.has(x) and not meijerg: + a = Wild('a', exclude=[x]) + b = Wild('b', exclude=[x]) + + M = g.base.match(a*x + b) + + if M is not None: + if g.exp == -1: + h = log(g.base) + elif conds != 'piecewise': + h = g.base**(g.exp + 1) / (g.exp + 1) + else: + h1 = log(g.base) + h2 = g.base**(g.exp + 1) / (g.exp + 1) + h = Piecewise((h2, Ne(g.exp, -1)), (h1, True)) + + parts.append(coeff * h / M[a]) + continue + + # poly(x) + # g(x) = ------- + # poly(x) + if g.is_rational_function(x) and not (manual or meijerg or risch): + parts.append(coeff * ratint(g, x)) + continue + + if not (manual or meijerg or risch): + # g(x) = Mul(trig) + h = trigintegrate(g, x, conds=conds) + if h is not None: + parts.append(coeff * h) + continue + + # g(x) has at least a DiracDelta term + h = deltaintegrate(g, x) + if h is not None: + parts.append(coeff * h) + continue + + from .singularityfunctions import singularityintegrate + # g(x) has at least a Singularity Function term + h = singularityintegrate(g, x) + if h is not None: + parts.append(coeff * h) + continue + + # Try risch again. + if risch is not False: + try: + h, i = risch_integrate(g, x, + separate_integral=True, conds=conds) + except NotImplementedError: + h = None + else: + if i: + h = h + i.doit(risch=False) + + parts.append(coeff*h) + continue + + # fall back to heurisch + if heurisch is not False: + from sympy.integrals.heurisch import (heurisch as heurisch_, + heurisch_wrapper) + try: + if conds == 'piecewise': + h = heurisch_wrapper(g, x, hints=[]) + else: + h = heurisch_(g, x, hints=[]) + except PolynomialError: + # XXX: this exception means there is a bug in the + # implementation of heuristic Risch integration + # algorithm. + h = None + else: + h = None + + if meijerg is not False and h is None: + # rewrite using G functions + try: + h = meijerint_indefinite(g, x) + except NotImplementedError: + _debug('NotImplementedError from meijerint_definite') + if h is not None: + parts.append(coeff * h) + continue + + if h is None and manual is not False: + try: + result = manualintegrate(g, x) + if result is not None and not isinstance(result, Integral): + if result.has(Integral) and not manual: + # Try to have other algorithms do the integrals + # manualintegrate can't handle, + # unless we were asked to use manual only. + # Keep the rest of eval_kwargs in case another + # method was set to False already + new_eval_kwargs = eval_kwargs + new_eval_kwargs["manual"] = False + new_eval_kwargs["final"] = False + result = result.func(*[ + arg.doit(**new_eval_kwargs) if + arg.has(Integral) else arg + for arg in result.args + ]).expand(multinomial=False, + log=False, + power_exp=False, + power_base=False) + if not result.has(Integral): + parts.append(coeff * result) + continue + except (ValueError, PolynomialError): + # can't handle some SymPy expressions + pass + + # if we failed maybe it was because we had + # a product that could have been expanded, + # so let's try an expansion of the whole + # thing before giving up; we don't try this + # at the outset because there are things + # that cannot be solved unless they are + # NOT expanded e.g., x**x*(1+log(x)). There + # should probably be a checker somewhere in this + # routine to look for such cases and try to do + # collection on the expressions if they are already + # in an expanded form + if not h and len(args) == 1: + f = sincos_to_sum(f).expand(mul=True, deep=False) + if f.is_Add: + # Note: risch will be identical on the expanded + # expression, but maybe it will be able to pick out parts, + # like x*(exp(x) + erf(x)). + return self._eval_integral(f, x, **eval_kwargs) + + if h is not None: + parts.append(coeff * h) + else: + return None + + return Add(*parts) + + def _eval_lseries(self, x, logx=None, cdir=0): + expr = self.as_dummy() + symb = x + for l in expr.limits: + if x in l[1:]: + symb = l[0] + break + for term in expr.function.lseries(symb, logx): + yield integrate(term, *expr.limits) + + def _eval_nseries(self, x, n, logx=None, cdir=0): + symb = x + for l in self.limits: + if x in l[1:]: + symb = l[0] + break + terms, order = self.function.nseries( + x=symb, n=n, logx=logx).as_coeff_add(Order) + order = [o.subs(symb, x) for o in order] + return integrate(terms, *self.limits) + Add(*order)*x + + def _eval_as_leading_term(self, x, logx, cdir): + series_gen = self.args[0].lseries(x) + for leading_term in series_gen: + if leading_term != 0: + break + return integrate(leading_term, *self.args[1:]) + + def _eval_simplify(self, **kwargs): + expr = factor_terms(self) + if isinstance(expr, Integral): + from sympy.simplify.simplify import simplify + return expr.func(*[simplify(i, **kwargs) for i in expr.args]) + return expr.simplify(**kwargs) + + def as_sum(self, n=None, method="midpoint", evaluate=True): + """ + Approximates a definite integral by a sum. + + Parameters + ========== + + n : + The number of subintervals to use, optional. + method : + One of: 'left', 'right', 'midpoint', 'trapezoid'. + evaluate : bool + If False, returns an unevaluated Sum expression. The default + is True, evaluate the sum. + + Notes + ===== + + These methods of approximate integration are described in [1]. + + Examples + ======== + + >>> from sympy import Integral, sin, sqrt + >>> from sympy.abc import x, n + >>> e = Integral(sin(x), (x, 3, 7)) + >>> e + Integral(sin(x), (x, 3, 7)) + + For demonstration purposes, this interval will only be split into 2 + regions, bounded by [3, 5] and [5, 7]. + + The left-hand rule uses function evaluations at the left of each + interval: + + >>> e.as_sum(2, 'left') + 2*sin(5) + 2*sin(3) + + The midpoint rule uses evaluations at the center of each interval: + + >>> e.as_sum(2, 'midpoint') + 2*sin(4) + 2*sin(6) + + The right-hand rule uses function evaluations at the right of each + interval: + + >>> e.as_sum(2, 'right') + 2*sin(5) + 2*sin(7) + + The trapezoid rule uses function evaluations on both sides of the + intervals. This is equivalent to taking the average of the left and + right hand rule results: + + >>> s = e.as_sum(2, 'trapezoid') + >>> s + 2*sin(5) + sin(3) + sin(7) + >>> (e.as_sum(2, 'left') + e.as_sum(2, 'right'))/2 == s + True + + Here, the discontinuity at x = 0 can be avoided by using the + midpoint or right-hand method: + + >>> e = Integral(1/sqrt(x), (x, 0, 1)) + >>> e.as_sum(5).n(4) + 1.730 + >>> e.as_sum(10).n(4) + 1.809 + >>> e.doit().n(4) # the actual value is 2 + 2.000 + + The left- or trapezoid method will encounter the discontinuity and + return infinity: + + >>> e.as_sum(5, 'left') + zoo + + The number of intervals can be symbolic. If omitted, a dummy symbol + will be used for it. + + >>> e = Integral(x**2, (x, 0, 2)) + >>> e.as_sum(n, 'right').expand() + 8/3 + 4/n + 4/(3*n**2) + + This shows that the midpoint rule is more accurate, as its error + term decays as the square of n: + + >>> e.as_sum(method='midpoint').expand() + 8/3 - 2/(3*_n**2) + + A symbolic sum is returned with evaluate=False: + + >>> e.as_sum(n, 'midpoint', evaluate=False) + 2*Sum((2*_k/n - 1/n)**2, (_k, 1, n))/n + + See Also + ======== + + Integral.doit : Perform the integration using any hints + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Riemann_sum#Riemann_summation_methods + """ + + from sympy.concrete.summations import Sum + limits = self.limits + if len(limits) > 1: + raise NotImplementedError( + "Multidimensional midpoint rule not implemented yet") + else: + limit = limits[0] + if (len(limit) != 3 or limit[1].is_finite is False or + limit[2].is_finite is False): + raise ValueError("Expecting a definite integral over " + "a finite interval.") + if n is None: + n = Dummy('n', integer=True, positive=True) + else: + n = sympify(n) + if (n.is_positive is False or n.is_integer is False or + n.is_finite is False): + raise ValueError("n must be a positive integer, got %s" % n) + x, a, b = limit + dx = (b - a)/n + k = Dummy('k', integer=True, positive=True) + f = self.function + + if method == "left": + result = dx*Sum(f.subs(x, a + (k-1)*dx), (k, 1, n)) + elif method == "right": + result = dx*Sum(f.subs(x, a + k*dx), (k, 1, n)) + elif method == "midpoint": + result = dx*Sum(f.subs(x, a + k*dx - dx/2), (k, 1, n)) + elif method == "trapezoid": + result = dx*((f.subs(x, a) + f.subs(x, b))/2 + + Sum(f.subs(x, a + k*dx), (k, 1, n - 1))) + else: + raise ValueError("Unknown method %s" % method) + return result.doit() if evaluate else result + + def principal_value(self, **kwargs): + """ + Compute the Cauchy Principal Value of the definite integral of a real function in the given interval + on the real axis. + + Explanation + =========== + + In mathematics, the Cauchy principal value, is a method for assigning values to certain improper + integrals which would otherwise be undefined. + + Examples + ======== + + >>> from sympy import Integral, oo + >>> from sympy.abc import x + >>> Integral(x+1, (x, -oo, oo)).principal_value() + oo + >>> f = 1 / (x**3) + >>> Integral(f, (x, -oo, oo)).principal_value() + 0 + >>> Integral(f, (x, -10, 10)).principal_value() + 0 + >>> Integral(f, (x, -10, oo)).principal_value() + Integral(f, (x, -oo, 10)).principal_value() + 0 + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Cauchy_principal_value + .. [2] https://mathworld.wolfram.com/CauchyPrincipalValue.html + """ + if len(self.limits) != 1 or len(list(self.limits[0])) != 3: + raise ValueError("You need to insert a variable, lower_limit, and upper_limit correctly to calculate " + "cauchy's principal value") + x, a, b = self.limits[0] + if not (a.is_comparable and b.is_comparable and a <= b): + raise ValueError("The lower_limit must be smaller than or equal to the upper_limit to calculate " + "cauchy's principal value. Also, a and b need to be comparable.") + if a == b: + return S.Zero + + from sympy.calculus.singularities import singularities + + r = Dummy('r') + f = self.function + singularities_list = [s for s in singularities(f, x) if s.is_comparable and a <= s <= b] + for i in singularities_list: + if i in (a, b): + raise ValueError( + 'The principal value is not defined in the given interval due to singularity at %d.' % (i)) + F = integrate(f, x, **kwargs) + if F.has(Integral): + return self + if a is -oo and b is oo: + I = limit(F - F.subs(x, -x), x, oo) + else: + I = limit(F, x, b, '-') - limit(F, x, a, '+') + for s in singularities_list: + I += limit(((F.subs(x, s - r)) - F.subs(x, s + r)), r, 0, '+') + return I + + + +def integrate(*args, meijerg=None, conds='piecewise', risch=None, heurisch=None, manual=None, **kwargs): + """integrate(f, var, ...) + + .. deprecated:: 1.6 + + Using ``integrate()`` with :class:`~.Poly` is deprecated. Use + :meth:`.Poly.integrate` instead. See :ref:`deprecated-integrate-poly`. + + Explanation + =========== + + Compute definite or indefinite integral of one or more variables + using Risch-Norman algorithm and table lookup. This procedure is + able to handle elementary algebraic and transcendental functions + and also a huge class of special functions, including Airy, + Bessel, Whittaker and Lambert. + + var can be: + + - a symbol -- indefinite integration + - a tuple (symbol, a) -- indefinite integration with result + given with ``a`` replacing ``symbol`` + - a tuple (symbol, a, b) -- definite integration + + Several variables can be specified, in which case the result is + multiple integration. (If var is omitted and the integrand is + univariate, the indefinite integral in that variable will be performed.) + + Indefinite integrals are returned without terms that are independent + of the integration variables. (see examples) + + Definite improper integrals often entail delicate convergence + conditions. Pass conds='piecewise', 'separate' or 'none' to have + these returned, respectively, as a Piecewise function, as a separate + result (i.e. result will be a tuple), or not at all (default is + 'piecewise'). + + **Strategy** + + SymPy uses various approaches to definite integration. One method is to + find an antiderivative for the integrand, and then use the fundamental + theorem of calculus. Various functions are implemented to integrate + polynomial, rational and trigonometric functions, and integrands + containing DiracDelta terms. + + SymPy also implements the part of the Risch algorithm, which is a decision + procedure for integrating elementary functions, i.e., the algorithm can + either find an elementary antiderivative, or prove that one does not + exist. There is also a (very successful, albeit somewhat slow) general + implementation of the heuristic Risch algorithm. This algorithm will + eventually be phased out as more of the full Risch algorithm is + implemented. See the docstring of Integral._eval_integral() for more + details on computing the antiderivative using algebraic methods. + + The option risch=True can be used to use only the (full) Risch algorithm. + This is useful if you want to know if an elementary function has an + elementary antiderivative. If the indefinite Integral returned by this + function is an instance of NonElementaryIntegral, that means that the + Risch algorithm has proven that integral to be non-elementary. Note that + by default, additional methods (such as the Meijer G method outlined + below) are tried on these integrals, as they may be expressible in terms + of special functions, so if you only care about elementary answers, use + risch=True. Also note that an unevaluated Integral returned by this + function is not necessarily a NonElementaryIntegral, even with risch=True, + as it may just be an indication that the particular part of the Risch + algorithm needed to integrate that function is not yet implemented. + + Another family of strategies comes from re-writing the integrand in + terms of so-called Meijer G-functions. Indefinite integrals of a + single G-function can always be computed, and the definite integral + of a product of two G-functions can be computed from zero to + infinity. Various strategies are implemented to rewrite integrands + as G-functions, and use this information to compute integrals (see + the ``meijerint`` module). + + The option manual=True can be used to use only an algorithm that tries + to mimic integration by hand. This algorithm does not handle as many + integrands as the other algorithms implemented but may return results in + a more familiar form. The ``manualintegrate`` module has functions that + return the steps used (see the module docstring for more information). + + In general, the algebraic methods work best for computing + antiderivatives of (possibly complicated) combinations of elementary + functions. The G-function methods work best for computing definite + integrals from zero to infinity of moderately complicated + combinations of special functions, or indefinite integrals of very + simple combinations of special functions. + + The strategy employed by the integration code is as follows: + + - If computing a definite integral, and both limits are real, + and at least one limit is +- oo, try the G-function method of + definite integration first. + + - Try to find an antiderivative, using all available methods, ordered + by performance (that is try fastest method first, slowest last; in + particular polynomial integration is tried first, Meijer + G-functions second to last, and heuristic Risch last). + + - If still not successful, try G-functions irrespective of the + limits. + + The option meijerg=True, False, None can be used to, respectively: + always use G-function methods and no others, never use G-function + methods, or use all available methods (in order as described above). + It defaults to None. + + Examples + ======== + + >>> from sympy import integrate, log, exp, oo + >>> from sympy.abc import a, x, y + + >>> integrate(x*y, x) + x**2*y/2 + + >>> integrate(log(x), x) + x*log(x) - x + + >>> integrate(log(x), (x, 1, a)) + a*log(a) - a + 1 + + >>> integrate(x) + x**2/2 + + Terms that are independent of x are dropped by indefinite integration: + + >>> from sympy import sqrt + >>> integrate(sqrt(1 + x), (x, 0, x)) + 2*(x + 1)**(3/2)/3 - 2/3 + >>> integrate(sqrt(1 + x), x) + 2*(x + 1)**(3/2)/3 + + >>> integrate(x*y) + Traceback (most recent call last): + ... + ValueError: specify integration variables to integrate x*y + + Note that ``integrate(x)`` syntax is meant only for convenience + in interactive sessions and should be avoided in library code. + + >>> integrate(x**a*exp(-x), (x, 0, oo)) # same as conds='piecewise' + Piecewise((gamma(a + 1), re(a) > -1), + (Integral(x**a*exp(-x), (x, 0, oo)), True)) + + >>> integrate(x**a*exp(-x), (x, 0, oo), conds='none') + gamma(a + 1) + + >>> integrate(x**a*exp(-x), (x, 0, oo), conds='separate') + (gamma(a + 1), re(a) > -1) + + See Also + ======== + + Integral, Integral.doit + + """ + doit_flags = { + 'deep': False, + 'meijerg': meijerg, + 'conds': conds, + 'risch': risch, + 'heurisch': heurisch, + 'manual': manual + } + + integral = Integral(*args, **kwargs) + + if isinstance(integral, Integral): + return integral.doit(**doit_flags) + else: + new_args = [a.doit(**doit_flags) if isinstance(a, Integral) else a + for a in integral.args] + return integral.func(*new_args) + +def line_integrate(field, curve, vars): + """line_integrate(field, Curve, variables) + + Compute the line integral. + + Examples + ======== + + >>> from sympy import Curve, line_integrate, E, ln + >>> from sympy.abc import x, y, t + >>> C = Curve([E**t + 1, E**t - 1], (t, 0, ln(2))) + >>> line_integrate(x + y, C, [x, y]) + 3*sqrt(2) + + See Also + ======== + + sympy.integrals.integrals.integrate, Integral + """ + from sympy.geometry import Curve + F = sympify(field) + if not F: + raise ValueError( + "Expecting function specifying field as first argument.") + if not isinstance(curve, Curve): + raise ValueError("Expecting Curve entity as second argument.") + if not is_sequence(vars): + raise ValueError("Expecting ordered iterable for variables.") + if len(curve.functions) != len(vars): + raise ValueError("Field variable size does not match curve dimension.") + + if curve.parameter in vars: + raise ValueError("Curve parameter clashes with field parameters.") + + # Calculate derivatives for line parameter functions + # F(r) -> F(r(t)) and finally F(r(t)*r'(t)) + Ft = F + dldt = 0 + for i, var in enumerate(vars): + _f = curve.functions[i] + _dn = diff(_f, curve.parameter) + # ...arc length + dldt = dldt + (_dn * _dn) + Ft = Ft.subs(var, _f) + Ft = Ft * sqrt(dldt) + + integral = Integral(Ft, curve.limits).doit(deep=False) + return integral + + +### Property function dispatching ### + +@shape.register(Integral) +def _(expr): + return shape(expr.function) + +# Delayed imports +from .deltafunctions import deltaintegrate +from .meijerint import meijerint_definite, meijerint_indefinite, _debug +from .trigonometry import trigintegrate diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/intpoly.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/intpoly.py new file mode 100644 index 0000000000000000000000000000000000000000..38fd071183fb2192f4c1443d04c8f0ecfb6cc4ea --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/intpoly.py @@ -0,0 +1,1302 @@ +""" +Module to implement integration of uni/bivariate polynomials over +2D Polytopes and uni/bi/trivariate polynomials over 3D Polytopes. + +Uses evaluation techniques as described in Chin et al. (2015) [1]. + + +References +=========== + +.. [1] Chin, Eric B., Jean B. Lasserre, and N. Sukumar. "Numerical integration +of homogeneous functions on convex and nonconvex polygons and polyhedra." +Computational Mechanics 56.6 (2015): 967-981 + +PDF link : http://dilbert.engr.ucdavis.edu/~suku/quadrature/cls-integration.pdf +""" + +from functools import cmp_to_key + +from sympy.abc import x, y, z +from sympy.core import S, diff, Expr, Symbol +from sympy.core.sympify import _sympify +from sympy.geometry import Segment2D, Polygon, Point, Point2D +from sympy.polys.polytools import LC, gcd_list, degree_list, Poly +from sympy.simplify.simplify import nsimplify + + +def polytope_integrate(poly, expr=None, *, clockwise=False, max_degree=None): + """Integrates polynomials over 2/3-Polytopes. + + Explanation + =========== + + This function accepts the polytope in ``poly`` and the function in ``expr`` + (uni/bi/trivariate polynomials are implemented) and returns + the exact integral of ``expr`` over ``poly``. + + Parameters + ========== + + poly : The input Polygon. + + expr : The input polynomial. + + clockwise : Binary value to sort input points of 2-Polytope clockwise.(Optional) + + max_degree : The maximum degree of any monomial of the input polynomial.(Optional) + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy import Point, Polygon + >>> from sympy.integrals.intpoly import polytope_integrate + >>> polygon = Polygon(Point(0, 0), Point(0, 1), Point(1, 1), Point(1, 0)) + >>> polys = [1, x, y, x*y, x**2*y, x*y**2] + >>> expr = x*y + >>> polytope_integrate(polygon, expr) + 1/4 + >>> polytope_integrate(polygon, polys, max_degree=3) + {1: 1, x: 1/2, y: 1/2, x*y: 1/4, x*y**2: 1/6, x**2*y: 1/6} + """ + if clockwise: + if isinstance(poly, Polygon): + poly = Polygon(*point_sort(poly.vertices), evaluate=False) + else: + raise TypeError("clockwise=True works for only 2-Polytope" + "V-representation input") + + if isinstance(poly, Polygon): + # For Vertex Representation(2D case) + hp_params = hyperplane_parameters(poly) + facets = poly.sides + elif len(poly[0]) == 2: + # For Hyperplane Representation(2D case) + plen = len(poly) + if len(poly[0][0]) == 2: + intersections = [intersection(poly[(i - 1) % plen], poly[i], + "plane2D") + for i in range(0, plen)] + hp_params = poly + lints = len(intersections) + facets = [Segment2D(intersections[i], + intersections[(i + 1) % lints]) + for i in range(lints)] + else: + raise NotImplementedError("Integration for H-representation 3D" + "case not implemented yet.") + else: + # For Vertex Representation(3D case) + vertices = poly[0] + facets = poly[1:] + hp_params = hyperplane_parameters(facets, vertices) + + if max_degree is None: + if expr is None: + raise TypeError('Input expression must be a valid SymPy expression') + return main_integrate3d(expr, facets, vertices, hp_params) + + if max_degree is not None: + result = {} + if expr is not None: + f_expr = [] + for e in expr: + _ = decompose(e) + if len(_) == 1 and not _.popitem()[0]: + f_expr.append(e) + elif Poly(e).total_degree() <= max_degree: + f_expr.append(e) + expr = f_expr + + if not isinstance(expr, list) and expr is not None: + raise TypeError('Input polynomials must be list of expressions') + + if len(hp_params[0][0]) == 3: + result_dict = main_integrate3d(0, facets, vertices, hp_params, + max_degree) + else: + result_dict = main_integrate(0, facets, hp_params, max_degree) + + if expr is None: + return result_dict + + for poly in expr: + poly = _sympify(poly) + if poly not in result: + if poly.is_zero: + result[S.Zero] = S.Zero + continue + integral_value = S.Zero + monoms = decompose(poly, separate=True) + for monom in monoms: + monom = nsimplify(monom) + coeff, m = strip(monom) + integral_value += result_dict[m] * coeff + result[poly] = integral_value + return result + + if expr is None: + raise TypeError('Input expression must be a valid SymPy expression') + + return main_integrate(expr, facets, hp_params) + + +def strip(monom): + if monom.is_zero: + return S.Zero, S.Zero + elif monom.is_number: + return monom, S.One + else: + coeff = LC(monom) + return coeff, monom / coeff + +def _polynomial_integrate(polynomials, facets, hp_params): + dims = (x, y) + dim_length = len(dims) + integral_value = S.Zero + for deg in polynomials: + poly_contribute = S.Zero + facet_count = 0 + for hp in hp_params: + value_over_boundary = integration_reduction(facets, + facet_count, + hp[0], hp[1], + polynomials[deg], + dims, deg) + poly_contribute += value_over_boundary * (hp[1] / norm(hp[0])) + facet_count += 1 + poly_contribute /= (dim_length + deg) + integral_value += poly_contribute + + return integral_value + + +def main_integrate3d(expr, facets, vertices, hp_params, max_degree=None): + """Function to translate the problem of integrating uni/bi/tri-variate + polynomials over a 3-Polytope to integrating over its faces. + This is done using Generalized Stokes' Theorem and Euler's Theorem. + + Parameters + ========== + + expr : + The input polynomial. + facets : + Faces of the 3-Polytope(expressed as indices of `vertices`). + vertices : + Vertices that constitute the Polytope. + hp_params : + Hyperplane Parameters of the facets. + max_degree : optional + Max degree of constituent monomial in given list of polynomial. + + Examples + ======== + + >>> from sympy.integrals.intpoly import main_integrate3d, \ + hyperplane_parameters + >>> cube = [[(0, 0, 0), (0, 0, 5), (0, 5, 0), (0, 5, 5), (5, 0, 0),\ + (5, 0, 5), (5, 5, 0), (5, 5, 5)],\ + [2, 6, 7, 3], [3, 7, 5, 1], [7, 6, 4, 5], [1, 5, 4, 0],\ + [3, 1, 0, 2], [0, 4, 6, 2]] + >>> vertices = cube[0] + >>> faces = cube[1:] + >>> hp_params = hyperplane_parameters(faces, vertices) + >>> main_integrate3d(1, faces, vertices, hp_params) + -125 + """ + result = {} + dims = (x, y, z) + dim_length = len(dims) + if max_degree: + grad_terms = gradient_terms(max_degree, 3) + flat_list = [term for z_terms in grad_terms + for x_term in z_terms + for term in x_term] + + for term in flat_list: + result[term[0]] = 0 + + for facet_count, hp in enumerate(hp_params): + a, b = hp[0], hp[1] + x0 = vertices[facets[facet_count][0]] + + for i, monom in enumerate(flat_list): + # Every monomial is a tuple : + # (term, x_degree, y_degree, z_degree, value over boundary) + expr, x_d, y_d, z_d, z_index, y_index, x_index, _ = monom + degree = x_d + y_d + z_d + if b.is_zero: + value_over_face = S.Zero + else: + value_over_face = \ + integration_reduction_dynamic(facets, facet_count, a, + b, expr, degree, dims, + x_index, y_index, + z_index, x0, grad_terms, + i, vertices, hp) + monom[7] = value_over_face + result[expr] += value_over_face * \ + (b / norm(a)) / (dim_length + x_d + y_d + z_d) + return result + else: + integral_value = S.Zero + polynomials = decompose(expr) + for deg in polynomials: + poly_contribute = S.Zero + facet_count = 0 + for i, facet in enumerate(facets): + hp = hp_params[i] + if hp[1].is_zero: + continue + pi = polygon_integrate(facet, hp, i, facets, vertices, expr, deg) + poly_contribute += pi *\ + (hp[1] / norm(tuple(hp[0]))) + facet_count += 1 + poly_contribute /= (dim_length + deg) + integral_value += poly_contribute + return integral_value + + +def main_integrate(expr, facets, hp_params, max_degree=None): + """Function to translate the problem of integrating univariate/bivariate + polynomials over a 2-Polytope to integrating over its boundary facets. + This is done using Generalized Stokes's Theorem and Euler's Theorem. + + Parameters + ========== + + expr : + The input polynomial. + facets : + Facets(Line Segments) of the 2-Polytope. + hp_params : + Hyperplane Parameters of the facets. + max_degree : optional + The maximum degree of any monomial of the input polynomial. + + >>> from sympy.abc import x, y + >>> from sympy.integrals.intpoly import main_integrate,\ + hyperplane_parameters + >>> from sympy import Point, Polygon + >>> triangle = Polygon(Point(0, 3), Point(5, 3), Point(1, 1)) + >>> facets = triangle.sides + >>> hp_params = hyperplane_parameters(triangle) + >>> main_integrate(x**2 + y**2, facets, hp_params) + 325/6 + """ + dims = (x, y) + dim_length = len(dims) + result = {} + + if max_degree: + grad_terms = [[0, 0, 0, 0]] + gradient_terms(max_degree) + + for facet_count, hp in enumerate(hp_params): + a, b = hp[0], hp[1] + x0 = facets[facet_count].points[0] + + for i, monom in enumerate(grad_terms): + # Every monomial is a tuple : + # (term, x_degree, y_degree, value over boundary) + m, x_d, y_d, _ = monom + value = result.get(m, None) + degree = S.Zero + if b.is_zero: + value_over_boundary = S.Zero + else: + degree = x_d + y_d + value_over_boundary = \ + integration_reduction_dynamic(facets, facet_count, a, + b, m, degree, dims, x_d, + y_d, max_degree, x0, + grad_terms, i) + monom[3] = value_over_boundary + if value is not None: + result[m] += value_over_boundary * \ + (b / norm(a)) / (dim_length + degree) + else: + result[m] = value_over_boundary * \ + (b / norm(a)) / (dim_length + degree) + return result + else: + if not isinstance(expr, list): + polynomials = decompose(expr) + return _polynomial_integrate(polynomials, facets, hp_params) + else: + return {e: _polynomial_integrate(decompose(e), facets, hp_params) for e in expr} + + +def polygon_integrate(facet, hp_param, index, facets, vertices, expr, degree): + """Helper function to integrate the input uni/bi/trivariate polynomial + over a certain face of the 3-Polytope. + + Parameters + ========== + + facet : + Particular face of the 3-Polytope over which ``expr`` is integrated. + index : + The index of ``facet`` in ``facets``. + facets : + Faces of the 3-Polytope(expressed as indices of `vertices`). + vertices : + Vertices that constitute the facet. + expr : + The input polynomial. + degree : + Degree of ``expr``. + + Examples + ======== + + >>> from sympy.integrals.intpoly import polygon_integrate + >>> cube = [[(0, 0, 0), (0, 0, 5), (0, 5, 0), (0, 5, 5), (5, 0, 0),\ + (5, 0, 5), (5, 5, 0), (5, 5, 5)],\ + [2, 6, 7, 3], [3, 7, 5, 1], [7, 6, 4, 5], [1, 5, 4, 0],\ + [3, 1, 0, 2], [0, 4, 6, 2]] + >>> facet = cube[1] + >>> facets = cube[1:] + >>> vertices = cube[0] + >>> polygon_integrate(facet, [(0, 1, 0), 5], 0, facets, vertices, 1, 0) + -25 + """ + expr = S(expr) + if expr.is_zero: + return S.Zero + result = S.Zero + x0 = vertices[facet[0]] + facet_len = len(facet) + for i, fac in enumerate(facet): + side = (vertices[fac], vertices[facet[(i + 1) % facet_len]]) + result += distance_to_side(x0, side, hp_param[0]) *\ + lineseg_integrate(facet, i, side, expr, degree) + if not expr.is_number: + expr = diff(expr, x) * x0[0] + diff(expr, y) * x0[1] +\ + diff(expr, z) * x0[2] + result += polygon_integrate(facet, hp_param, index, facets, vertices, + expr, degree - 1) + result /= (degree + 2) + return result + + +def distance_to_side(point, line_seg, A): + """Helper function to compute the signed distance between given 3D point + and a line segment. + + Parameters + ========== + + point : 3D Point + line_seg : Line Segment + + Examples + ======== + + >>> from sympy.integrals.intpoly import distance_to_side + >>> point = (0, 0, 0) + >>> distance_to_side(point, [(0, 0, 1), (0, 1, 0)], (1, 0, 0)) + -sqrt(2)/2 + """ + x1, x2 = line_seg + rev_normal = [-1 * S(i)/norm(A) for i in A] + vector = [x2[i] - x1[i] for i in range(0, 3)] + vector = [vector[i]/norm(vector) for i in range(0, 3)] + + n_side = cross_product((0, 0, 0), rev_normal, vector) + vectorx0 = [line_seg[0][i] - point[i] for i in range(0, 3)] + dot_product = sum(vectorx0[i] * n_side[i] for i in range(0, 3)) + + return dot_product + + +def lineseg_integrate(polygon, index, line_seg, expr, degree): + """Helper function to compute the line integral of ``expr`` over ``line_seg``. + + Parameters + =========== + + polygon : + Face of a 3-Polytope. + index : + Index of line_seg in polygon. + line_seg : + Line Segment. + + Examples + ======== + + >>> from sympy.integrals.intpoly import lineseg_integrate + >>> polygon = [(0, 5, 0), (5, 5, 0), (5, 5, 5), (0, 5, 5)] + >>> line_seg = [(0, 5, 0), (5, 5, 0)] + >>> lineseg_integrate(polygon, 0, line_seg, 1, 0) + 5 + """ + expr = _sympify(expr) + if expr.is_zero: + return S.Zero + result = S.Zero + x0 = line_seg[0] + distance = norm(tuple([line_seg[1][i] - line_seg[0][i] for i in + range(3)])) + if isinstance(expr, Expr): + expr_dict = {x: line_seg[1][0], + y: line_seg[1][1], + z: line_seg[1][2]} + result += distance * expr.subs(expr_dict) + else: + result += distance * expr + + expr = diff(expr, x) * x0[0] + diff(expr, y) * x0[1] +\ + diff(expr, z) * x0[2] + + result += lineseg_integrate(polygon, index, line_seg, expr, degree - 1) + result /= (degree + 1) + return result + + +def integration_reduction(facets, index, a, b, expr, dims, degree): + """Helper method for main_integrate. Returns the value of the input + expression evaluated over the polytope facet referenced by a given index. + + Parameters + =========== + + facets : + List of facets of the polytope. + index : + Index referencing the facet to integrate the expression over. + a : + Hyperplane parameter denoting direction. + b : + Hyperplane parameter denoting distance. + expr : + The expression to integrate over the facet. + dims : + List of symbols denoting axes. + degree : + Degree of the homogeneous polynomial. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy.integrals.intpoly import integration_reduction,\ + hyperplane_parameters + >>> from sympy import Point, Polygon + >>> triangle = Polygon(Point(0, 3), Point(5, 3), Point(1, 1)) + >>> facets = triangle.sides + >>> a, b = hyperplane_parameters(triangle)[0] + >>> integration_reduction(facets, 0, a, b, 1, (x, y), 0) + 5 + """ + expr = _sympify(expr) + if expr.is_zero: + return expr + + value = S.Zero + x0 = facets[index].points[0] + m = len(facets) + gens = (x, y) + + inner_product = diff(expr, gens[0]) * x0[0] + diff(expr, gens[1]) * x0[1] + + if inner_product != 0: + value += integration_reduction(facets, index, a, b, + inner_product, dims, degree - 1) + + value += left_integral2D(m, index, facets, x0, expr, gens) + + return value/(len(dims) + degree - 1) + + +def left_integral2D(m, index, facets, x0, expr, gens): + """Computes the left integral of Eq 10 in Chin et al. + For the 2D case, the integral is just an evaluation of the polynomial + at the intersection of two facets which is multiplied by the distance + between the first point of facet and that intersection. + + Parameters + ========== + + m : + No. of hyperplanes. + index : + Index of facet to find intersections with. + facets : + List of facets(Line Segments in 2D case). + x0 : + First point on facet referenced by index. + expr : + Input polynomial + gens : + Generators which generate the polynomial + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy.integrals.intpoly import left_integral2D + >>> from sympy import Point, Polygon + >>> triangle = Polygon(Point(0, 3), Point(5, 3), Point(1, 1)) + >>> facets = triangle.sides + >>> left_integral2D(3, 0, facets, facets[0].points[0], 1, (x, y)) + 5 + """ + value = S.Zero + for j in range(m): + intersect = () + if j in ((index - 1) % m, (index + 1) % m): + intersect = intersection(facets[index], facets[j], "segment2D") + if intersect: + distance_origin = norm(tuple(map(lambda x, y: x - y, + intersect, x0))) + if is_vertex(intersect): + if isinstance(expr, Expr): + if len(gens) == 3: + expr_dict = {gens[0]: intersect[0], + gens[1]: intersect[1], + gens[2]: intersect[2]} + else: + expr_dict = {gens[0]: intersect[0], + gens[1]: intersect[1]} + value += distance_origin * expr.subs(expr_dict) + else: + value += distance_origin * expr + return value + + +def integration_reduction_dynamic(facets, index, a, b, expr, degree, dims, + x_index, y_index, max_index, x0, + monomial_values, monom_index, vertices=None, + hp_param=None): + """The same integration_reduction function which uses a dynamic + programming approach to compute terms by using the values of the integral + of previously computed terms. + + Parameters + ========== + + facets : + Facets of the Polytope. + index : + Index of facet to find intersections with.(Used in left_integral()). + a, b : + Hyperplane parameters. + expr : + Input monomial. + degree : + Total degree of ``expr``. + dims : + Tuple denoting axes variables. + x_index : + Exponent of 'x' in ``expr``. + y_index : + Exponent of 'y' in ``expr``. + max_index : + Maximum exponent of any monomial in ``monomial_values``. + x0 : + First point on ``facets[index]``. + monomial_values : + List of monomial values constituting the polynomial. + monom_index : + Index of monomial whose integration is being found. + vertices : optional + Coordinates of vertices constituting the 3-Polytope. + hp_param : optional + Hyperplane Parameter of the face of the facets[index]. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy.integrals.intpoly import (integration_reduction_dynamic, \ + hyperplane_parameters) + >>> from sympy import Point, Polygon + >>> triangle = Polygon(Point(0, 3), Point(5, 3), Point(1, 1)) + >>> facets = triangle.sides + >>> a, b = hyperplane_parameters(triangle)[0] + >>> x0 = facets[0].points[0] + >>> monomial_values = [[0, 0, 0, 0], [1, 0, 0, 5],\ + [y, 0, 1, 15], [x, 1, 0, None]] + >>> integration_reduction_dynamic(facets, 0, a, b, x, 1, (x, y), 1, 0, 1,\ + x0, monomial_values, 3) + 25/2 + """ + value = S.Zero + m = len(facets) + + if expr == S.Zero: + return expr + + if len(dims) == 2: + if not expr.is_number: + _, x_degree, y_degree, _ = monomial_values[monom_index] + x_index = monom_index - max_index + \ + x_index - 2 if x_degree > 0 else 0 + y_index = monom_index - 1 if y_degree > 0 else 0 + x_value, y_value =\ + monomial_values[x_index][3], monomial_values[y_index][3] + + value += x_degree * x_value * x0[0] + y_degree * y_value * x0[1] + + value += left_integral2D(m, index, facets, x0, expr, dims) + else: + # For 3D use case the max_index contains the z_degree of the term + z_index = max_index + if not expr.is_number: + x_degree, y_degree, z_degree = y_index,\ + z_index - x_index - y_index, x_index + x_value = monomial_values[z_index - 1][y_index - 1][x_index][7]\ + if x_degree > 0 else 0 + y_value = monomial_values[z_index - 1][y_index][x_index][7]\ + if y_degree > 0 else 0 + z_value = monomial_values[z_index - 1][y_index][x_index - 1][7]\ + if z_degree > 0 else 0 + + value += x_degree * x_value * x0[0] + y_degree * y_value * x0[1] \ + + z_degree * z_value * x0[2] + + value += left_integral3D(facets, index, expr, + vertices, hp_param, degree) + return value / (len(dims) + degree - 1) + + +def left_integral3D(facets, index, expr, vertices, hp_param, degree): + """Computes the left integral of Eq 10 in Chin et al. + + Explanation + =========== + + For the 3D case, this is the sum of the integral values over constituting + line segments of the face (which is accessed by facets[index]) multiplied + by the distance between the first point of facet and that line segment. + + Parameters + ========== + + facets : + List of faces of the 3-Polytope. + index : + Index of face over which integral is to be calculated. + expr : + Input polynomial. + vertices : + List of vertices that constitute the 3-Polytope. + hp_param : + The hyperplane parameters of the face. + degree : + Degree of the ``expr``. + + Examples + ======== + + >>> from sympy.integrals.intpoly import left_integral3D + >>> cube = [[(0, 0, 0), (0, 0, 5), (0, 5, 0), (0, 5, 5), (5, 0, 0),\ + (5, 0, 5), (5, 5, 0), (5, 5, 5)],\ + [2, 6, 7, 3], [3, 7, 5, 1], [7, 6, 4, 5], [1, 5, 4, 0],\ + [3, 1, 0, 2], [0, 4, 6, 2]] + >>> facets = cube[1:] + >>> vertices = cube[0] + >>> left_integral3D(facets, 3, 1, vertices, ([0, -1, 0], -5), 0) + -50 + """ + value = S.Zero + facet = facets[index] + x0 = vertices[facet[0]] + facet_len = len(facet) + for i, fac in enumerate(facet): + side = (vertices[fac], vertices[facet[(i + 1) % facet_len]]) + value += distance_to_side(x0, side, hp_param[0]) * \ + lineseg_integrate(facet, i, side, expr, degree) + return value + + +def gradient_terms(binomial_power=0, no_of_gens=2): + """Returns a list of all the possible monomials between + 0 and y**binomial_power for 2D case and z**binomial_power + for 3D case. + + Parameters + ========== + + binomial_power : + Power upto which terms are generated. + no_of_gens : + Denotes whether terms are being generated for 2D or 3D case. + + Examples + ======== + + >>> from sympy.integrals.intpoly import gradient_terms + >>> gradient_terms(2) + [[1, 0, 0, 0], [y, 0, 1, 0], [y**2, 0, 2, 0], [x, 1, 0, 0], + [x*y, 1, 1, 0], [x**2, 2, 0, 0]] + >>> gradient_terms(2, 3) + [[[[1, 0, 0, 0, 0, 0, 0, 0]]], [[[y, 0, 1, 0, 1, 0, 0, 0], + [z, 0, 0, 1, 1, 0, 1, 0]], [[x, 1, 0, 0, 1, 1, 0, 0]]], + [[[y**2, 0, 2, 0, 2, 0, 0, 0], [y*z, 0, 1, 1, 2, 0, 1, 0], + [z**2, 0, 0, 2, 2, 0, 2, 0]], [[x*y, 1, 1, 0, 2, 1, 0, 0], + [x*z, 1, 0, 1, 2, 1, 1, 0]], [[x**2, 2, 0, 0, 2, 2, 0, 0]]]] + """ + if no_of_gens == 2: + count = 0 + terms = [None] * int((binomial_power ** 2 + 3 * binomial_power + 2) / 2) + for x_count in range(0, binomial_power + 1): + for y_count in range(0, binomial_power - x_count + 1): + terms[count] = [x**x_count*y**y_count, + x_count, y_count, 0] + count += 1 + else: + terms = [[[[x ** x_count * y ** y_count * + z ** (z_count - y_count - x_count), + x_count, y_count, z_count - y_count - x_count, + z_count, x_count, z_count - y_count - x_count, 0] + for y_count in range(z_count - x_count, -1, -1)] + for x_count in range(0, z_count + 1)] + for z_count in range(0, binomial_power + 1)] + return terms + + +def hyperplane_parameters(poly, vertices=None): + """A helper function to return the hyperplane parameters + of which the facets of the polytope are a part of. + + Parameters + ========== + + poly : + The input 2/3-Polytope. + vertices : + Vertex indices of 3-Polytope. + + Examples + ======== + + >>> from sympy import Point, Polygon + >>> from sympy.integrals.intpoly import hyperplane_parameters + >>> hyperplane_parameters(Polygon(Point(0, 3), Point(5, 3), Point(1, 1))) + [((0, 1), 3), ((1, -2), -1), ((-2, -1), -3)] + >>> cube = [[(0, 0, 0), (0, 0, 5), (0, 5, 0), (0, 5, 5), (5, 0, 0),\ + (5, 0, 5), (5, 5, 0), (5, 5, 5)],\ + [2, 6, 7, 3], [3, 7, 5, 1], [7, 6, 4, 5], [1, 5, 4, 0],\ + [3, 1, 0, 2], [0, 4, 6, 2]] + >>> hyperplane_parameters(cube[1:], cube[0]) + [([0, -1, 0], -5), ([0, 0, -1], -5), ([-1, 0, 0], -5), + ([0, 1, 0], 0), ([1, 0, 0], 0), ([0, 0, 1], 0)] + """ + if isinstance(poly, Polygon): + vertices = list(poly.vertices) + [poly.vertices[0]] # Close the polygon + params = [None] * (len(vertices) - 1) + + for i in range(len(vertices) - 1): + v1 = vertices[i] + v2 = vertices[i + 1] + + a1 = v1[1] - v2[1] + a2 = v2[0] - v1[0] + b = v2[0] * v1[1] - v2[1] * v1[0] + + factor = gcd_list([a1, a2, b]) + + b = S(b) / factor + a = (S(a1) / factor, S(a2) / factor) + params[i] = (a, b) + else: + params = [None] * len(poly) + for i, polygon in enumerate(poly): + v1, v2, v3 = [vertices[vertex] for vertex in polygon[:3]] + normal = cross_product(v1, v2, v3) + b = sum(normal[j] * v1[j] for j in range(0, 3)) + fac = gcd_list(normal) + if fac.is_zero: + fac = 1 + normal = [j / fac for j in normal] + b = b / fac + params[i] = (normal, b) + return params + + +def cross_product(v1, v2, v3): + """Returns the cross-product of vectors (v2 - v1) and (v3 - v1) + That is : (v2 - v1) X (v3 - v1) + """ + v2 = [v2[j] - v1[j] for j in range(0, 3)] + v3 = [v3[j] - v1[j] for j in range(0, 3)] + return [v3[2] * v2[1] - v3[1] * v2[2], + v3[0] * v2[2] - v3[2] * v2[0], + v3[1] * v2[0] - v3[0] * v2[1]] + + +def best_origin(a, b, lineseg, expr): + """Helper method for polytope_integrate. Currently not used in the main + algorithm. + + Explanation + =========== + + Returns a point on the lineseg whose vector inner product with the + divergence of `expr` yields an expression with the least maximum + total power. + + Parameters + ========== + + a : + Hyperplane parameter denoting direction. + b : + Hyperplane parameter denoting distance. + lineseg : + Line segment on which to find the origin. + expr : + The expression which determines the best point. + + Algorithm(currently works only for 2D use case) + =============================================== + + 1 > Firstly, check for edge cases. Here that would refer to vertical + or horizontal lines. + + 2 > If input expression is a polynomial containing more than one generator + then find out the total power of each of the generators. + + x**2 + 3 + x*y + x**4*y**5 ---> {x: 7, y: 6} + + If expression is a constant value then pick the first boundary point + of the line segment. + + 3 > First check if a point exists on the line segment where the value of + the highest power generator becomes 0. If not check if the value of + the next highest becomes 0. If none becomes 0 within line segment + constraints then pick the first boundary point of the line segment. + Actually, any point lying on the segment can be picked as best origin + in the last case. + + Examples + ======== + + >>> from sympy.integrals.intpoly import best_origin + >>> from sympy.abc import x, y + >>> from sympy import Point, Segment2D + >>> l = Segment2D(Point(0, 3), Point(1, 1)) + >>> expr = x**3*y**7 + >>> best_origin((2, 1), 3, l, expr) + (0, 3.0) + """ + a1, b1 = lineseg.points[0] + + def x_axis_cut(ls): + """Returns the point where the input line segment + intersects the x-axis. + + Parameters + ========== + + ls : + Line segment + """ + p, q = ls.points + if p.y.is_zero: + return tuple(p) + elif q.y.is_zero: + return tuple(q) + elif p.y/q.y < S.Zero: + return p.y * (p.x - q.x)/(q.y - p.y) + p.x, S.Zero + else: + return () + + def y_axis_cut(ls): + """Returns the point where the input line segment + intersects the y-axis. + + Parameters + ========== + + ls : + Line segment + """ + p, q = ls.points + if p.x.is_zero: + return tuple(p) + elif q.x.is_zero: + return tuple(q) + elif p.x/q.x < S.Zero: + return S.Zero, p.x * (p.y - q.y)/(q.x - p.x) + p.y + else: + return () + + gens = (x, y) + power_gens = {} + + for i in gens: + power_gens[i] = S.Zero + + if len(gens) > 1: + # Special case for vertical and horizontal lines + if len(gens) == 2: + if a[0] == 0: + if y_axis_cut(lineseg): + return S.Zero, b/a[1] + else: + return a1, b1 + elif a[1] == 0: + if x_axis_cut(lineseg): + return b/a[0], S.Zero + else: + return a1, b1 + + if isinstance(expr, Expr): # Find the sum total of power of each + if expr.is_Add: # generator and store in a dictionary. + for monomial in expr.args: + if monomial.is_Pow: + if monomial.args[0] in gens: + power_gens[monomial.args[0]] += monomial.args[1] + else: + for univariate in monomial.args: + term_type = len(univariate.args) + if term_type == 0 and univariate in gens: + power_gens[univariate] += 1 + elif term_type == 2 and univariate.args[0] in gens: + power_gens[univariate.args[0]] +=\ + univariate.args[1] + elif expr.is_Mul: + for term in expr.args: + term_type = len(term.args) + if term_type == 0 and term in gens: + power_gens[term] += 1 + elif term_type == 2 and term.args[0] in gens: + power_gens[term.args[0]] += term.args[1] + elif expr.is_Pow: + power_gens[expr.args[0]] = expr.args[1] + elif expr.is_Symbol: + power_gens[expr] += 1 + else: # If `expr` is a constant take first vertex of the line segment. + return a1, b1 + + # TODO : This part is quite hacky. Should be made more robust with + # TODO : respect to symbol names and scalable w.r.t higher dimensions. + power_gens = sorted(power_gens.items(), key=lambda k: str(k[0])) + if power_gens[0][1] >= power_gens[1][1]: + if y_axis_cut(lineseg): + x0 = (S.Zero, b / a[1]) + elif x_axis_cut(lineseg): + x0 = (b / a[0], S.Zero) + else: + x0 = (a1, b1) + else: + if x_axis_cut(lineseg): + x0 = (b/a[0], S.Zero) + elif y_axis_cut(lineseg): + x0 = (S.Zero, b/a[1]) + else: + x0 = (a1, b1) + else: + x0 = (b/a[0]) + return x0 + + +def decompose(expr, separate=False): + """Decomposes an input polynomial into homogeneous ones of + smaller or equal degree. + + Explanation + =========== + + Returns a dictionary with keys as the degree of the smaller + constituting polynomials. Values are the constituting polynomials. + + Parameters + ========== + + expr : Expr + Polynomial(SymPy expression). + separate : bool + If True then simply return a list of the constituent monomials + If not then break up the polynomial into constituent homogeneous + polynomials. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy.integrals.intpoly import decompose + >>> decompose(x**2 + x*y + x + y + x**3*y**2 + y**5) + {1: x + y, 2: x**2 + x*y, 5: x**3*y**2 + y**5} + >>> decompose(x**2 + x*y + x + y + x**3*y**2 + y**5, True) + {x, x**2, y, y**5, x*y, x**3*y**2} + """ + poly_dict = {} + + if isinstance(expr, Expr) and not expr.is_number: + if expr.is_Symbol: + poly_dict[1] = expr + elif expr.is_Add: + symbols = expr.atoms(Symbol) + degrees = [(sum(degree_list(monom, *symbols)), monom) + for monom in expr.args] + if separate: + return {monom[1] for monom in degrees} + else: + for monom in degrees: + degree, term = monom + if poly_dict.get(degree): + poly_dict[degree] += term + else: + poly_dict[degree] = term + elif expr.is_Pow: + _, degree = expr.args + poly_dict[degree] = expr + else: # Now expr can only be of `Mul` type + degree = 0 + for term in expr.args: + term_type = len(term.args) + if term_type == 0 and term.is_Symbol: + degree += 1 + elif term_type == 2: + degree += term.args[1] + poly_dict[degree] = expr + else: + poly_dict[0] = expr + + if separate: + return set(poly_dict.values()) + return poly_dict + + +def point_sort(poly, normal=None, clockwise=True): + """Returns the same polygon with points sorted in clockwise or + anti-clockwise order. + + Note that it's necessary for input points to be sorted in some order + (clockwise or anti-clockwise) for the integration algorithm to work. + As a convention algorithm has been implemented keeping clockwise + orientation in mind. + + Parameters + ========== + + poly: + 2D or 3D Polygon. + normal : optional + The normal of the plane which the 3-Polytope is a part of. + clockwise : bool, optional + Returns points sorted in clockwise order if True and + anti-clockwise if False. + + Examples + ======== + + >>> from sympy.integrals.intpoly import point_sort + >>> from sympy import Point + >>> point_sort([Point(0, 0), Point(1, 0), Point(1, 1)]) + [Point2D(1, 1), Point2D(1, 0), Point2D(0, 0)] + """ + pts = poly.vertices if isinstance(poly, Polygon) else poly + n = len(pts) + if n < 2: + return list(pts) + + order = S.One if clockwise else S.NegativeOne + dim = len(pts[0]) + if dim == 2: + center = Point(sum((vertex.x for vertex in pts)) / n, + sum((vertex.y for vertex in pts)) / n) + else: + center = Point(sum((vertex.x for vertex in pts)) / n, + sum((vertex.y for vertex in pts)) / n, + sum((vertex.z for vertex in pts)) / n) + + def compare(a, b): + if a.x - center.x >= S.Zero and b.x - center.x < S.Zero: + return -order + elif a.x - center.x < 0 and b.x - center.x >= 0: + return order + elif a.x - center.x == 0 and b.x - center.x == 0: + if a.y - center.y >= 0 or b.y - center.y >= 0: + return -order if a.y > b.y else order + return -order if b.y > a.y else order + + det = (a.x - center.x) * (b.y - center.y) -\ + (b.x - center.x) * (a.y - center.y) + if det < 0: + return -order + elif det > 0: + return order + + first = (a.x - center.x) * (a.x - center.x) +\ + (a.y - center.y) * (a.y - center.y) + second = (b.x - center.x) * (b.x - center.x) +\ + (b.y - center.y) * (b.y - center.y) + return -order if first > second else order + + def compare3d(a, b): + det = cross_product(center, a, b) + dot_product = sum(det[i] * normal[i] for i in range(0, 3)) + if dot_product < 0: + return -order + elif dot_product > 0: + return order + + return sorted(pts, key=cmp_to_key(compare if dim==2 else compare3d)) + + +def norm(point): + """Returns the Euclidean norm of a point from origin. + + Parameters + ========== + + point: + This denotes a point in the dimension_al spac_e. + + Examples + ======== + + >>> from sympy.integrals.intpoly import norm + >>> from sympy import Point + >>> norm(Point(2, 7)) + sqrt(53) + """ + half = S.Half + if isinstance(point, (list, tuple)): + return sum(coord ** 2 for coord in point) ** half + elif isinstance(point, Point): + if isinstance(point, Point2D): + return (point.x ** 2 + point.y ** 2) ** half + else: + return (point.x ** 2 + point.y ** 2 + point.z) ** half + elif isinstance(point, dict): + return sum(i**2 for i in point.values()) ** half + + +def intersection(geom_1, geom_2, intersection_type): + """Returns intersection between geometric objects. + + Explanation + =========== + + Note that this function is meant for use in integration_reduction and + at that point in the calling function the lines denoted by the segments + surely intersect within segment boundaries. Coincident lines are taken + to be non-intersecting. Also, the hyperplane intersection for 2D case is + also implemented. + + Parameters + ========== + + geom_1, geom_2: + The input line segments. + + Examples + ======== + + >>> from sympy.integrals.intpoly import intersection + >>> from sympy import Point, Segment2D + >>> l1 = Segment2D(Point(1, 1), Point(3, 5)) + >>> l2 = Segment2D(Point(2, 0), Point(2, 5)) + >>> intersection(l1, l2, "segment2D") + (2, 3) + >>> p1 = ((-1, 0), 0) + >>> p2 = ((0, 1), 1) + >>> intersection(p1, p2, "plane2D") + (0, 1) + """ + if intersection_type[:-2] == "segment": + if intersection_type == "segment2D": + x1, y1 = geom_1.points[0] + x2, y2 = geom_1.points[1] + x3, y3 = geom_2.points[0] + x4, y4 = geom_2.points[1] + elif intersection_type == "segment3D": + x1, y1, z1 = geom_1.points[0] + x2, y2, z2 = geom_1.points[1] + x3, y3, z3 = geom_2.points[0] + x4, y4, z4 = geom_2.points[1] + + denom = (x1 - x2) * (y3 - y4) - (y1 - y2) * (x3 - x4) + if denom: + t1 = x1 * y2 - y1 * x2 + t2 = x3 * y4 - x4 * y3 + return (S(t1 * (x3 - x4) - t2 * (x1 - x2)) / denom, + S(t1 * (y3 - y4) - t2 * (y1 - y2)) / denom) + if intersection_type[:-2] == "plane": + if intersection_type == "plane2D": # Intersection of hyperplanes + a1x, a1y = geom_1[0] + a2x, a2y = geom_2[0] + b1, b2 = geom_1[1], geom_2[1] + + denom = a1x * a2y - a2x * a1y + if denom: + return (S(b1 * a2y - b2 * a1y) / denom, + S(b2 * a1x - b1 * a2x) / denom) + + +def is_vertex(ent): + """If the input entity is a vertex return True. + + Parameter + ========= + + ent : + Denotes a geometric entity representing a point. + + Examples + ======== + + >>> from sympy import Point + >>> from sympy.integrals.intpoly import is_vertex + >>> is_vertex((2, 3)) + True + >>> is_vertex((2, 3, 6)) + True + >>> is_vertex(Point(2, 3)) + True + """ + if isinstance(ent, tuple): + if len(ent) in [2, 3]: + return True + elif isinstance(ent, Point): + return True + return False + + +def plot_polytope(poly): + """Plots the 2D polytope using the functions written in plotting + module which in turn uses matplotlib backend. + + Parameter + ========= + + poly: + Denotes a 2-Polytope. + """ + from sympy.plotting.plot import Plot, List2DSeries + + xl = [vertex.x for vertex in poly.vertices] + yl = [vertex.y for vertex in poly.vertices] + + xl.append(poly.vertices[0].x) # Closing the polygon + yl.append(poly.vertices[0].y) + + l2ds = List2DSeries(xl, yl) + p = Plot(l2ds, axes='label_axes=True') + p.show() + + +def plot_polynomial(expr): + """Plots the polynomial using the functions written in + plotting module which in turn uses matplotlib backend. + + Parameter + ========= + + expr: + Denotes a polynomial(SymPy expression). + """ + from sympy.plotting.plot import plot3d, plot + gens = expr.free_symbols + if len(gens) == 2: + plot3d(expr) + else: + plot(expr) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/laplace.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/laplace.py new file mode 100644 index 0000000000000000000000000000000000000000..604c4a2711440f13c62f0d778e382e4daaf33148 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/laplace.py @@ -0,0 +1,2377 @@ +"""Laplace Transforms""" +import sys +import sympy +from sympy.core import S, pi, I +from sympy.core.add import Add +from sympy.core.cache import cacheit +from sympy.core.expr import Expr +from sympy.core.function import ( + AppliedUndef, Derivative, expand, expand_complex, expand_mul, expand_trig, + Lambda, WildFunction, diff, Subs) +from sympy.core.mul import Mul, prod +from sympy.core.relational import ( + _canonical, Ge, Gt, Lt, Unequality, Eq, Ne, Relational) +from sympy.core.sorting import ordered +from sympy.core.symbol import Dummy, symbols, Wild +from sympy.functions.elementary.complexes import ( + re, im, arg, Abs, polar_lift, periodic_argument) +from sympy.functions.elementary.exponential import exp, log +from sympy.functions.elementary.hyperbolic import cosh, coth, sinh, asinh +from sympy.functions.elementary.miscellaneous import Max, Min, sqrt +from sympy.functions.elementary.piecewise import ( + Piecewise, piecewise_exclusive) +from sympy.functions.elementary.trigonometric import cos, sin, atan, sinc +from sympy.functions.special.bessel import besseli, besselj, besselk, bessely +from sympy.functions.special.delta_functions import DiracDelta, Heaviside +from sympy.functions.special.error_functions import erf, erfc, Ei +from sympy.functions.special.gamma_functions import ( + digamma, gamma, lowergamma, uppergamma) +from sympy.functions.special.singularity_functions import SingularityFunction +from sympy.integrals import integrate, Integral +from sympy.integrals.transforms import ( + _simplify, IntegralTransform, IntegralTransformError) +from sympy.logic.boolalg import to_cnf, conjuncts, disjuncts, Or, And +from sympy.matrices.matrixbase import MatrixBase +from sympy.polys.matrices.linsolve import _lin_eq2dict +from sympy.polys.polyerrors import PolynomialError +from sympy.polys.polyroots import roots +from sympy.polys.polytools import Poly +from sympy.polys.rationaltools import together +from sympy.polys.rootoftools import RootSum +from sympy.utilities.exceptions import ( + sympy_deprecation_warning, SymPyDeprecationWarning, ignore_warnings) +from sympy.utilities.misc import debugf + +_LT_level = 0 + + +def DEBUG_WRAP(func): + def wrap(*args, **kwargs): + from sympy import SYMPY_DEBUG + global _LT_level + + if not SYMPY_DEBUG: + return func(*args, **kwargs) + + if _LT_level == 0: + print('\n' + '-'*78, file=sys.stderr) + print('-LT- %s%s%s' % (' '*_LT_level, func.__name__, args), + file=sys.stderr) + _LT_level += 1 + if ( + func.__name__ == '_laplace_transform_integration' or + func.__name__ == '_inverse_laplace_transform_integration'): + sympy.SYMPY_DEBUG = False + print('**** %sIntegrating ...' % (' '*_LT_level), file=sys.stderr) + result = func(*args, **kwargs) + sympy.SYMPY_DEBUG = True + else: + result = func(*args, **kwargs) + _LT_level -= 1 + print('-LT- %s---> %s' % (' '*_LT_level, result), file=sys.stderr) + if _LT_level == 0: + print('-'*78 + '\n', file=sys.stderr) + return result + return wrap + + +def _debug(text): + from sympy import SYMPY_DEBUG + + if SYMPY_DEBUG: + print('-LT- %s%s' % (' '*_LT_level, text), file=sys.stderr) + + +def _simplifyconds(expr, s, a): + r""" + Naively simplify some conditions occurring in ``expr``, + given that `\operatorname{Re}(s) > a`. + + Examples + ======== + + >>> from sympy.integrals.laplace import _simplifyconds + >>> from sympy.abc import x + >>> from sympy import sympify as S + >>> _simplifyconds(abs(x**2) < 1, x, 1) + False + >>> _simplifyconds(abs(x**2) < 1, x, 2) + False + >>> _simplifyconds(abs(x**2) < 1, x, 0) + Abs(x**2) < 1 + >>> _simplifyconds(abs(1/x**2) < 1, x, 1) + True + >>> _simplifyconds(S(1) < abs(x), x, 1) + True + >>> _simplifyconds(S(1) < abs(1/x), x, 1) + False + + >>> from sympy import Ne + >>> _simplifyconds(Ne(1, x**3), x, 1) + True + >>> _simplifyconds(Ne(1, x**3), x, 2) + True + >>> _simplifyconds(Ne(1, x**3), x, 0) + Ne(1, x**3) + """ + + def power(ex): + if ex == s: + return 1 + if ex.is_Pow and ex.base == s: + return ex.exp + return None + + def bigger(ex1, ex2): + """ Return True only if |ex1| > |ex2|, False only if |ex1| < |ex2|. + Else return None. """ + if ex1.has(s) and ex2.has(s): + return None + if isinstance(ex1, Abs): + ex1 = ex1.args[0] + if isinstance(ex2, Abs): + ex2 = ex2.args[0] + if ex1.has(s): + return bigger(1/ex2, 1/ex1) + n = power(ex2) + if n is None: + return None + try: + if n > 0 and (Abs(ex1) <= Abs(a)**n) == S.true: + return False + if n < 0 and (Abs(ex1) >= Abs(a)**n) == S.true: + return True + except TypeError: + return None + + def replie(x, y): + """ simplify x < y """ + if (not (x.is_positive or isinstance(x, Abs)) + or not (y.is_positive or isinstance(y, Abs))): + return (x < y) + r = bigger(x, y) + if r is not None: + return not r + return (x < y) + + def replue(x, y): + b = bigger(x, y) + if b in (True, False): + return True + return Unequality(x, y) + + def repl(ex, *args): + if ex in (True, False): + return bool(ex) + return ex.replace(*args) + + from sympy.simplify.radsimp import collect_abs + expr = collect_abs(expr) + expr = repl(expr, Lt, replie) + expr = repl(expr, Gt, lambda x, y: replie(y, x)) + expr = repl(expr, Unequality, replue) + return S(expr) + + +@DEBUG_WRAP +def expand_dirac_delta(expr): + """ + Expand an expression involving DiractDelta to get it as a linear + combination of DiracDelta functions. + """ + return _lin_eq2dict(expr, expr.atoms(DiracDelta)) + + +@DEBUG_WRAP +def _laplace_transform_integration(f, t, s_, *, simplify): + """ The backend function for doing Laplace transforms by integration. + + This backend assumes that the frontend has already split sums + such that `f` is to an addition anymore. + """ + s = Dummy('s') + + if f.has(DiracDelta): + return None + + F = integrate(f*exp(-s*t), (t, S.Zero, S.Infinity)) + + if not F.has(Integral): + return _simplify(F.subs(s, s_), simplify), S.NegativeInfinity, S.true + + if not F.is_Piecewise: + return None + + F, cond = F.args[0] + if F.has(Integral): + return None + + def process_conds(conds): + """ Turn ``conds`` into a strip and auxiliary conditions. """ + from sympy.solvers.inequalities import _solve_inequality + a = S.NegativeInfinity + aux = S.true + conds = conjuncts(to_cnf(conds)) + p, q, w1, w2, w3, w4, w5 = symbols( + 'p q w1 w2 w3 w4 w5', cls=Wild, exclude=[s]) + patterns = ( + p*Abs(arg((s + w3)*q)) < w2, + p*Abs(arg((s + w3)*q)) <= w2, + Abs(periodic_argument((s + w3)**p*q, w1)) < w2, + Abs(periodic_argument((s + w3)**p*q, w1)) <= w2, + Abs(periodic_argument((polar_lift(s + w3))**p*q, w1)) < w2, + Abs(periodic_argument((polar_lift(s + w3))**p*q, w1)) <= w2) + for c in conds: + a_ = S.Infinity + aux_ = [] + for d in disjuncts(c): + if d.is_Relational and s in d.rhs.free_symbols: + d = d.reversed + if d.is_Relational and isinstance(d, (Ge, Gt)): + d = d.reversedsign + for pat in patterns: + m = d.match(pat) + if m: + break + if m and m[q].is_positive and m[w2]/m[p] == pi/2: + d = -re(s + m[w3]) < 0 + m = d.match(p - cos(w1*Abs(arg(s*w5))*w2)*Abs(s**w3)**w4 < 0) + if not m: + m = d.match( + cos(p - Abs(periodic_argument(s**w1*w5, q))*w2) * + Abs(s**w3)**w4 < 0) + if not m: + m = d.match( + p - cos( + Abs(periodic_argument(polar_lift(s)**w1*w5, q))*w2 + )*Abs(s**w3)**w4 < 0) + if m and all(m[wild].is_positive for wild in [ + w1, w2, w3, w4, w5]): + d = re(s) > m[p] + d_ = d.replace( + re, lambda x: x.expand().as_real_imag()[0]).subs(re(s), t) + if ( + not d.is_Relational or d.rel_op in ('==', '!=') + or d_.has(s) or not d_.has(t)): + aux_ += [d] + continue + soln = _solve_inequality(d_, t) + if not soln.is_Relational or soln.rel_op in ('==', '!='): + aux_ += [d] + continue + if soln.lts == t: + return None + else: + a_ = Min(soln.lts, a_) + if a_ is not S.Infinity: + a = Max(a_, a) + else: + aux = And(aux, Or(*aux_)) + return a, aux.canonical if aux.is_Relational else aux + + conds = [process_conds(c) for c in disjuncts(cond)] + conds2 = [x for x in conds if x[1] != + S.false and x[0] is not S.NegativeInfinity] + if not conds2: + conds2 = [x for x in conds if x[1] != S.false] + conds = list(ordered(conds2)) + + def cnt(expr): + if expr in (True, False): + return 0 + return expr.count_ops() + conds.sort(key=lambda x: (-x[0], cnt(x[1]))) + + if not conds: + return None + a, aux = conds[0] # XXX is [0] always the right one? + + def sbs(expr): + return expr.subs(s, s_) + if simplify: + F = _simplifyconds(F, s, a) + aux = _simplifyconds(aux, s, a) + return _simplify(F.subs(s, s_), simplify), sbs(a), _canonical(sbs(aux)) + + +@DEBUG_WRAP +def _laplace_deep_collect(f, t): + """ + This is an internal helper function that traverses through the expression + tree of `f(t)` and collects arguments. The purpose of it is that + anything like `f(w*t-1*t-c)` will be written as `f((w-1)*t-c)` such that + it can match `f(a*t+b)`. + """ + if not isinstance(f, Expr): + return f + if (p := f.as_poly(t)) is not None: + return p.as_expr() + func = f.func + args = [_laplace_deep_collect(arg, t) for arg in f.args] + return func(*args) + + +@cacheit +def _laplace_build_rules(): + """ + This is an internal helper function that returns the table of Laplace + transform rules in terms of the time variable `t` and the frequency + variable `s`. It is used by ``_laplace_apply_rules``. Each entry is a + tuple containing: + + (time domain pattern, + frequency-domain replacement, + condition for the rule to be applied, + convergence plane, + preparation function) + + The preparation function is a function with one argument that is applied + to the expression before matching. For most rules it should be + ``_laplace_deep_collect``. + """ + t = Dummy('t') + s = Dummy('s') + a = Wild('a', exclude=[t]) + b = Wild('b', exclude=[t]) + n = Wild('n', exclude=[t]) + tau = Wild('tau', exclude=[t]) + omega = Wild('omega', exclude=[t]) + def dco(f): return _laplace_deep_collect(f, t) + _debug('_laplace_build_rules is building rules') + + laplace_transform_rules = [ + (a, a/s, + S.true, S.Zero, dco), # 4.2.1 + (DiracDelta(a*t-b), exp(-s*b/a)/Abs(a), + Or(And(a > 0, b >= 0), And(a < 0, b <= 0)), + S.NegativeInfinity, dco), # Not in Bateman54 + (DiracDelta(a*t-b), S(0), + Or(And(a < 0, b >= 0), And(a > 0, b <= 0)), + S.NegativeInfinity, dco), # Not in Bateman54 + (Heaviside(a*t-b), exp(-s*b/a)/s, + And(a > 0, b > 0), S.Zero, dco), # 4.4.1 + (Heaviside(a*t-b), (1-exp(-s*b/a))/s, + And(a < 0, b < 0), S.Zero, dco), # 4.4.1 + (Heaviside(a*t-b), 1/s, + And(a > 0, b <= 0), S.Zero, dco), # 4.4.1 + (Heaviside(a*t-b), 0, + And(a < 0, b > 0), S.Zero, dco), # 4.4.1 + (t, 1/s**2, + S.true, S.Zero, dco), # 4.2.3 + (1/(a*t+b), -exp(-b/a*s)*Ei(-b/a*s)/a, + Abs(arg(b/a)) < pi, S.Zero, dco), # 4.2.6 + (1/sqrt(a*t+b), sqrt(a*pi/s)*exp(b/a*s)*erfc(sqrt(b/a*s))/a, + Abs(arg(b/a)) < pi, S.Zero, dco), # 4.2.18 + ((a*t+b)**(-S(3)/2), + 2*b**(-S(1)/2)-2*(pi*s/a)**(S(1)/2)*exp(b/a*s) * erfc(sqrt(b/a*s))/a, + Abs(arg(b/a)) < pi, S.Zero, dco), # 4.2.20 + (sqrt(t)/(t+b), sqrt(pi/s)-pi*sqrt(b)*exp(b*s)*erfc(sqrt(b*s)), + Abs(arg(b)) < pi, S.Zero, dco), # 4.2.22 + (1/(a*sqrt(t) + t**(3/2)), pi*a**(S(1)/2)*exp(a*s)*erfc(sqrt(a*s)), + S.true, S.Zero, dco), # Not in Bateman54 + (t**n, gamma(n+1)/s**(n+1), + n > -1, S.Zero, dco), # 4.3.1 + ((a*t+b)**n, uppergamma(n+1, b/a*s)*exp(-b/a*s)/s**(n+1)/a, + And(n > -1, Abs(arg(b/a)) < pi), S.Zero, dco), # 4.3.4 + (t**n/(t+a), a**n*gamma(n+1)*uppergamma(-n, a*s), + And(n > -1, Abs(arg(a)) < pi), S.Zero, dco), # 4.3.7 + (exp(a*t-tau), exp(-tau)/(s-a), + S.true, re(a), dco), # 4.5.1 + (t*exp(a*t-tau), exp(-tau)/(s-a)**2, + S.true, re(a), dco), # 4.5.2 + (t**n*exp(a*t), gamma(n+1)/(s-a)**(n+1), + re(n) > -1, re(a), dco), # 4.5.3 + (exp(-a*t**2), sqrt(pi/4/a)*exp(s**2/4/a)*erfc(s/sqrt(4*a)), + re(a) > 0, S.Zero, dco), # 4.5.21 + (t*exp(-a*t**2), + 1/(2*a)-2/sqrt(pi)/(4*a)**(S(3)/2)*s*erfc(s/sqrt(4*a)), + re(a) > 0, S.Zero, dco), # 4.5.22 + (exp(-a/t), 2*sqrt(a/s)*besselk(1, 2*sqrt(a*s)), + re(a) >= 0, S.Zero, dco), # 4.5.25 + (sqrt(t)*exp(-a/t), + S(1)/2*sqrt(pi/s**3)*(1+2*sqrt(a*s))*exp(-2*sqrt(a*s)), + re(a) >= 0, S.Zero, dco), # 4.5.26 + (exp(-a/t)/sqrt(t), sqrt(pi/s)*exp(-2*sqrt(a*s)), + re(a) >= 0, S.Zero, dco), # 4.5.27 + (exp(-a/t)/(t*sqrt(t)), sqrt(pi/a)*exp(-2*sqrt(a*s)), + re(a) > 0, S.Zero, dco), # 4.5.28 + (t**n*exp(-a/t), 2*(a/s)**((n+1)/2)*besselk(n+1, 2*sqrt(a*s)), + re(a) > 0, S.Zero, dco), # 4.5.29 + # TODO: rules with sqrt(a*t) and sqrt(a/t) have stopped working after + # changes to as_base_exp + # (exp(-2*sqrt(a*t)), + # s**(-1)-sqrt(pi*a)*s**(-S(3)/2)*exp(a/s) * erfc(sqrt(a/s)), + # Abs(arg(a)) < pi, S.Zero, dco), # 4.5.31 + # (exp(-2*sqrt(a*t))/sqrt(t), (pi/s)**(S(1)/2)*exp(a/s)*erfc(sqrt(a/s)), + # Abs(arg(a)) < pi, S.Zero, dco), # 4.5.33 + (exp(-a*exp(-t)), a**(-s)*lowergamma(s, a), + S.true, S.Zero, dco), # 4.5.36 + (exp(-a*exp(t)), a**s*uppergamma(-s, a), + re(a) > 0, S.Zero, dco), # 4.5.37 + (log(a*t), -log(exp(S.EulerGamma)*s/a)/s, + a > 0, S.Zero, dco), # 4.6.1 + (log(1+a*t), -exp(s/a)/s*Ei(-s/a), + Abs(arg(a)) < pi, S.Zero, dco), # 4.6.4 + (log(a*t+b), (log(b)-exp(s/b/a)/s*a*Ei(-s/b))/s*a, + And(a > 0, Abs(arg(b)) < pi), S.Zero, dco), # 4.6.5 + (log(t)/sqrt(t), -sqrt(pi/s)*log(4*s*exp(S.EulerGamma)), + S.true, S.Zero, dco), # 4.6.9 + (t**n*log(t), gamma(n+1)*s**(-n-1)*(digamma(n+1)-log(s)), + re(n) > -1, S.Zero, dco), # 4.6.11 + (log(a*t)**2, (log(exp(S.EulerGamma)*s/a)**2+pi**2/6)/s, + a > 0, S.Zero, dco), # 4.6.13 + (sin(omega*t), omega/(s**2+omega**2), + S.true, Abs(im(omega)), dco), # 4,7,1 + (Abs(sin(omega*t)), omega/(s**2+omega**2)*coth(pi*s/2/omega), + omega > 0, S.Zero, dco), # 4.7.2 + (sin(omega*t)/t, atan(omega/s), + S.true, Abs(im(omega)), dco), # 4.7.16 + (sin(omega*t)**2/t, log(1+4*omega**2/s**2)/4, + S.true, 2*Abs(im(omega)), dco), # 4.7.17 + (sin(omega*t)**2/t**2, + omega*atan(2*omega/s)-s*log(1+4*omega**2/s**2)/4, + S.true, 2*Abs(im(omega)), dco), # 4.7.20 + # (sin(2*sqrt(a*t)), sqrt(pi*a)/s/sqrt(s)*exp(-a/s), + # S.true, S.Zero, dco), # 4.7.32 + # (sin(2*sqrt(a*t))/t, pi*erf(sqrt(a/s)), + # S.true, S.Zero, dco), # 4.7.34 + (cos(omega*t), s/(s**2+omega**2), + S.true, Abs(im(omega)), dco), # 4.7.43 + (cos(omega*t)**2, (s**2+2*omega**2)/(s**2+4*omega**2)/s, + S.true, 2*Abs(im(omega)), dco), # 4.7.45 + # (sqrt(t)*cos(2*sqrt(a*t)), sqrt(pi)/2*s**(-S(5)/2)*(s-2*a)*exp(-a/s), + # S.true, S.Zero, dco), # 4.7.66 + # (cos(2*sqrt(a*t))/sqrt(t), sqrt(pi/s)*exp(-a/s), + # S.true, S.Zero, dco), # 4.7.67 + (sin(a*t)*sin(b*t), 2*a*b*s/(s**2+(a+b)**2)/(s**2+(a-b)**2), + S.true, Abs(im(a))+Abs(im(b)), dco), # 4.7.78 + (cos(a*t)*sin(b*t), b*(s**2-a**2+b**2)/(s**2+(a+b)**2)/(s**2+(a-b)**2), + S.true, Abs(im(a))+Abs(im(b)), dco), # 4.7.79 + (cos(a*t)*cos(b*t), s*(s**2+a**2+b**2)/(s**2+(a+b)**2)/(s**2+(a-b)**2), + S.true, Abs(im(a))+Abs(im(b)), dco), # 4.7.80 + (sinh(a*t), a/(s**2-a**2), + S.true, Abs(re(a)), dco), # 4.9.1 + (cosh(a*t), s/(s**2-a**2), + S.true, Abs(re(a)), dco), # 4.9.2 + (sinh(a*t)**2, 2*a**2/(s**3-4*a**2*s), + S.true, 2*Abs(re(a)), dco), # 4.9.3 + (cosh(a*t)**2, (s**2-2*a**2)/(s**3-4*a**2*s), + S.true, 2*Abs(re(a)), dco), # 4.9.4 + (sinh(a*t)/t, log((s+a)/(s-a))/2, + S.true, Abs(re(a)), dco), # 4.9.12 + (t**n*sinh(a*t), gamma(n+1)/2*((s-a)**(-n-1)-(s+a)**(-n-1)), + n > -2, Abs(a), dco), # 4.9.18 + (t**n*cosh(a*t), gamma(n+1)/2*((s-a)**(-n-1)+(s+a)**(-n-1)), + n > -1, Abs(a), dco), # 4.9.19 + # TODO + # (sinh(2*sqrt(a*t)), sqrt(pi*a)/s/sqrt(s)*exp(a/s), + # S.true, S.Zero, dco), # 4.9.34 + # (cosh(2*sqrt(a*t)), 1/s+sqrt(pi*a)/s/sqrt(s)*exp(a/s)*erf(sqrt(a/s)), + # S.true, S.Zero, dco), # 4.9.35 + # ( + # sqrt(t)*sinh(2*sqrt(a*t)), + # pi**(S(1)/2)*s**(-S(5)/2)*(s/2+a) * + # exp(a/s)*erf(sqrt(a/s))-a**(S(1)/2)*s**(-2), + # S.true, S.Zero, dco), # 4.9.36 + # (sqrt(t)*cosh(2*sqrt(a*t)), pi**(S(1)/2)*s**(-S(5)/2)*(s/2+a)*exp(a/s), + # S.true, S.Zero, dco), # 4.9.37 + # (sinh(2*sqrt(a*t))/sqrt(t), + # pi**(S(1)/2)*s**(-S(1)/2)*exp(a/s) * erf(sqrt(a/s)), + # S.true, S.Zero, dco), # 4.9.38 + # (cosh(2*sqrt(a*t))/sqrt(t), pi**(S(1)/2)*s**(-S(1)/2)*exp(a/s), + # S.true, S.Zero, dco), # 4.9.39 + # (sinh(sqrt(a*t))**2/sqrt(t), pi**(S(1)/2)/2*s**(-S(1)/2)*(exp(a/s)-1), + # S.true, S.Zero, dco), # 4.9.40 + # (cosh(sqrt(a*t))**2/sqrt(t), pi**(S(1)/2)/2*s**(-S(1)/2)*(exp(a/s)+1), + # S.true, S.Zero, dco), # 4.9.41 + (erf(a*t), exp(s**2/(2*a)**2)*erfc(s/(2*a))/s, + 4*Abs(arg(a)) < pi, S.Zero, dco), # 4.12.2 + # (erf(sqrt(a*t)), sqrt(a)/sqrt(s+a)/s, + # S.true, Max(S.Zero, -re(a)), dco), # 4.12.4 + # (exp(a*t)*erf(sqrt(a*t)), sqrt(a)/sqrt(s)/(s-a), + # S.true, Max(S.Zero, re(a)), dco), # 4.12.5 + # (erf(sqrt(a/t)/2), (1-exp(-sqrt(a*s)))/s, + # re(a) > 0, S.Zero, dco), # 4.12.6 + # (erfc(sqrt(a*t)), (sqrt(s+a)-sqrt(a))/sqrt(s+a)/s, + # S.true, -re(a), dco), # 4.12.9 + # (exp(a*t)*erfc(sqrt(a*t)), 1/(s+sqrt(a*s)), + # S.true, S.Zero, dco), # 4.12.10 + # (erfc(sqrt(a/t)/2), exp(-sqrt(a*s))/s, + # re(a) > 0, S.Zero, dco), # 4.2.11 + (besselj(n, a*t), a**n/(sqrt(s**2+a**2)*(s+sqrt(s**2+a**2))**n), + re(n) > -1, Abs(im(a)), dco), # 4.14.1 + (t**b*besselj(n, a*t), + 2**n/sqrt(pi)*gamma(n+S.Half)*a**n*(s**2+a**2)**(-n-S.Half), + And(re(n) > -S.Half, Eq(b, n)), Abs(im(a)), dco), # 4.14.7 + (t**b*besselj(n, a*t), + 2**(n+1)/sqrt(pi)*gamma(n+S(3)/2)*a**n*s*(s**2+a**2)**(-n-S(3)/2), + And(re(n) > -1, Eq(b, n+1)), Abs(im(a)), dco), # 4.14.8 + # (besselj(0, 2*sqrt(a*t)), exp(-a/s)/s, + # S.true, S.Zero, dco), # 4.14.25 + # (t**(b)*besselj(n, 2*sqrt(a*t)), a**(n/2)*s**(-n-1)*exp(-a/s), + # And(re(n) > -1, Eq(b, n*S.Half)), S.Zero, dco), # 4.14.30 + (besselj(0, a*sqrt(t**2+b*t)), + exp(b*s-b*sqrt(s**2+a**2))/sqrt(s**2+a**2), + Abs(arg(b)) < pi, Abs(im(a)), dco), # 4.15.19 + (besseli(n, a*t), a**n/(sqrt(s**2-a**2)*(s+sqrt(s**2-a**2))**n), + re(n) > -1, Abs(re(a)), dco), # 4.16.1 + (t**b*besseli(n, a*t), + 2**n/sqrt(pi)*gamma(n+S.Half)*a**n*(s**2-a**2)**(-n-S.Half), + And(re(n) > -S.Half, Eq(b, n)), Abs(re(a)), dco), # 4.16.6 + (t**b*besseli(n, a*t), + 2**(n+1)/sqrt(pi)*gamma(n+S(3)/2)*a**n*s*(s**2-a**2)**(-n-S(3)/2), + And(re(n) > -1, Eq(b, n+1)), Abs(re(a)), dco), # 4.16.7 + # (t**(b)*besseli(n, 2*sqrt(a*t)), a**(n/2)*s**(-n-1)*exp(a/s), + # And(re(n) > -1, Eq(b, n*S.Half)), S.Zero, dco), # 4.16.18 + (bessely(0, a*t), -2/pi*asinh(s/a)/sqrt(s**2+a**2), + S.true, Abs(im(a)), dco), # 4.15.44 + (besselk(0, a*t), log((s + sqrt(s**2-a**2))/a)/(sqrt(s**2-a**2)), + S.true, -re(a), dco) # 4.16.23 + ] + return laplace_transform_rules, t, s + + +@DEBUG_WRAP +def _laplace_rule_timescale(f, t, s): + """ + This function applies the time-scaling rule of the Laplace transform in + a straight-forward way. For example, if it gets ``(f(a*t), t, s)``, it will + compute ``LaplaceTransform(f(t)/a, t, s/a)`` if ``a>0``. + """ + + a = Wild('a', exclude=[t]) + g = WildFunction('g', nargs=1) + ma1 = f.match(g) + if ma1: + arg = ma1[g].args[0].collect(t) + ma2 = arg.match(a*t) + if ma2 and ma2[a].is_positive and ma2[a] != 1: + _debug(' rule: time scaling (4.1.4)') + r, pr, cr = _laplace_transform( + 1/ma2[a]*ma1[g].func(t), t, s/ma2[a], simplify=False) + return (r, pr, cr) + return None + + +@DEBUG_WRAP +def _laplace_rule_heaviside(f, t, s): + """ + This function deals with time-shifted Heaviside step functions. If the time + shift is positive, it applies the time-shift rule of the Laplace transform. + For example, if it gets ``(Heaviside(t-a)*f(t), t, s)``, it will compute + ``exp(-a*s)*LaplaceTransform(f(t+a), t, s)``. + + If the time shift is negative, the Heaviside function is simply removed + as it means nothing to the Laplace transform. + + The function does not remove a factor ``Heaviside(t)``; this is done by + the simple rules. + """ + + a = Wild('a', exclude=[t]) + y = Wild('y') + g = Wild('g') + if ma1 := f.match(Heaviside(y) * g): + if ma2 := ma1[y].match(t - a): + if ma2[a].is_positive: + _debug(' rule: time shift (4.1.4)') + r, pr, cr = _laplace_transform( + ma1[g].subs(t, t + ma2[a]), t, s, simplify=False) + return (exp(-ma2[a] * s) * r, pr, cr) + if ma2[a].is_negative: + _debug( + ' rule: Heaviside factor; negative time shift (4.1.4)') + r, pr, cr = _laplace_transform(ma1[g], t, s, simplify=False) + return (r, pr, cr) + if ma2 := ma1[y].match(a - t): + if ma2[a].is_positive: + _debug(' rule: Heaviside window open') + r, pr, cr = _laplace_transform( + (1 - Heaviside(t - ma2[a])) * ma1[g], t, s, simplify=False) + return (r, pr, cr) + if ma2[a].is_negative: + _debug(' rule: Heaviside window closed') + return (0, 0, S.true) + return None + + +@DEBUG_WRAP +def _laplace_rule_exp(f, t, s): + """ + If this function finds a factor ``exp(a*t)``, it applies the + frequency-shift rule of the Laplace transform and adjusts the convergence + plane accordingly. For example, if it gets ``(exp(-a*t)*f(t), t, s)``, it + will compute ``LaplaceTransform(f(t), t, s+a)``. + """ + + a = Wild('a', exclude=[t]) + y = Wild('y') + z = Wild('z') + ma1 = f.match(exp(y)*z) + if ma1: + ma2 = ma1[y].collect(t).match(a*t) + if ma2: + _debug(' rule: multiply with exp (4.1.5)') + r, pr, cr = _laplace_transform(ma1[z], t, s-ma2[a], + simplify=False) + return (r, pr+re(ma2[a]), cr) + return None + + +@DEBUG_WRAP +def _laplace_rule_delta(f, t, s): + """ + If this function finds a factor ``DiracDelta(b*t-a)``, it applies the + masking property of the delta distribution. For example, if it gets + ``(DiracDelta(t-a)*f(t), t, s)``, it will return + ``(f(a)*exp(-a*s), -a, True)``. + """ + # This rule is not in Bateman54 + + a = Wild('a', exclude=[t]) + b = Wild('b', exclude=[t]) + + y = Wild('y') + z = Wild('z') + ma1 = f.match(DiracDelta(y)*z) + if ma1 and not ma1[z].has(DiracDelta): + ma2 = ma1[y].collect(t).match(b*t-a) + if ma2: + _debug(' rule: multiply with DiracDelta') + loc = ma2[a]/ma2[b] + if re(loc) >= 0 and im(loc) == 0: + fn = exp(-ma2[a]/ma2[b]*s)*ma1[z] + if fn.has(sin, cos): + # Then it may be possible that a sinc() is present in the + # term; let's try this: + fn = fn.rewrite(sinc).ratsimp() + n, d = [x.subs(t, ma2[a]/ma2[b]) for x in fn.as_numer_denom()] + if d != 0: + return (n/d/ma2[b], S.NegativeInfinity, S.true) + else: + return None + else: + return (0, S.NegativeInfinity, S.true) + if ma1[y].is_polynomial(t): + ro = roots(ma1[y], t) + if ro != {} and set(ro.values()) == {1}: + slope = diff(ma1[y], t) + r = Add( + *[exp(-x*s)*ma1[z].subs(t, s)/slope.subs(t, x) + for x in list(ro.keys()) if im(x) == 0 and re(x) >= 0]) + return (r, S.NegativeInfinity, S.true) + return None + + +@DEBUG_WRAP +def _laplace_trig_split(fn): + """ + Helper function for `_laplace_rule_trig`. This function returns two terms + `f` and `g`. `f` contains all product terms with sin, cos, sinh, cosh in + them; `g` contains everything else. + """ + trigs = [S.One] + other = [S.One] + for term in Mul.make_args(fn): + if term.has(sin, cos, sinh, cosh, exp): + trigs.append(term) + else: + other.append(term) + f = Mul(*trigs) + g = Mul(*other) + return f, g + + +@DEBUG_WRAP +def _laplace_trig_expsum(f, t): + """ + Helper function for `_laplace_rule_trig`. This function expects the `f` + from `_laplace_trig_split`. It returns two lists `xm` and `xn`. `xm` is + a list of dictionaries with keys `k` and `a` representing a function + `k*exp(a*t)`. `xn` is a list of all terms that cannot be brought into + that form, which may happen, e.g., when a trigonometric function has + another function in its argument. + """ + c1 = Wild('c1', exclude=[t]) + c0 = Wild('c0', exclude=[t]) + p = Wild('p', exclude=[t]) + xm = [] + xn = [] + + x1 = f.rewrite(exp).expand() + + for term in Add.make_args(x1): + if not term.has(t): + xm.append({'k': term, 'a': 0, re: 0, im: 0}) + continue + term = _laplace_deep_collect(term.powsimp(combine='exp'), t) + + if (r := term.match(p*exp(c1*t+c0))) is not None: + xm.append({ + 'k': r[p]*exp(r[c0]), 'a': r[c1], + re: re(r[c1]), im: im(r[c1])}) + else: + xn.append(term) + return xm, xn + + +@DEBUG_WRAP +def _laplace_trig_ltex(xm, t, s): + """ + Helper function for `_laplace_rule_trig`. This function takes the list of + exponentials `xm` from `_laplace_trig_expsum` and simplifies complex + conjugate and real symmetric poles. It returns the result as a sum and + the convergence plane. + """ + results = [] + planes = [] + + def _simpc(coeffs): + nc = coeffs.copy() + for k in range(len(nc)): + ri = nc[k].as_real_imag() + if ri[0].has(im): + nc[k] = nc[k].rewrite(cos) + else: + nc[k] = (ri[0] + I*ri[1]).rewrite(cos) + return nc + + def _quadpole(t1, k1, k2, k3, s): + a, k0, a_r, a_i = t1['a'], t1['k'], t1[re], t1[im] + nc = [ + k0 + k1 + k2 + k3, + a*(k0 + k1 - k2 - k3) - 2*I*a_i*k1 + 2*I*a_i*k2, + ( + a**2*(-k0 - k1 - k2 - k3) + + a*(4*I*a_i*k0 + 4*I*a_i*k3) + + 4*a_i**2*k0 + 4*a_i**2*k3), + ( + a**3*(-k0 - k1 + k2 + k3) + + a**2*(4*I*a_i*k0 + 2*I*a_i*k1 - 2*I*a_i*k2 - 4*I*a_i*k3) + + a*(4*a_i**2*k0 - 4*a_i**2*k3)) + ] + dc = [ + S.One, S.Zero, 2*a_i**2 - 2*a_r**2, + S.Zero, a_i**4 + 2*a_i**2*a_r**2 + a_r**4] + n = Add( + *[x*s**y for x, y in zip(_simpc(nc), range(len(nc))[::-1])]) + d = Add( + *[x*s**y for x, y in zip(dc, range(len(dc))[::-1])]) + return n/d + + def _ccpole(t1, k1, s): + a, k0, a_r, a_i = t1['a'], t1['k'], t1[re], t1[im] + nc = [k0 + k1, -a*k0 - a*k1 + 2*I*a_i*k0] + dc = [S.One, -2*a_r, a_i**2 + a_r**2] + n = Add( + *[x*s**y for x, y in zip(_simpc(nc), range(len(nc))[::-1])]) + d = Add( + *[x*s**y for x, y in zip(dc, range(len(dc))[::-1])]) + return n/d + + def _rspole(t1, k2, s): + a, k0, a_r, a_i = t1['a'], t1['k'], t1[re], t1[im] + nc = [k0 + k2, a*k0 - a*k2 - 2*I*a_i*k0] + dc = [S.One, -2*I*a_i, -a_i**2 - a_r**2] + n = Add( + *[x*s**y for x, y in zip(_simpc(nc), range(len(nc))[::-1])]) + d = Add( + *[x*s**y for x, y in zip(dc, range(len(dc))[::-1])]) + return n/d + + def _sypole(t1, k3, s): + a, k0 = t1['a'], t1['k'] + nc = [k0 + k3, a*(k0 - k3)] + dc = [S.One, S.Zero, -a**2] + n = Add( + *[x*s**y for x, y in zip(_simpc(nc), range(len(nc))[::-1])]) + d = Add( + *[x*s**y for x, y in zip(dc, range(len(dc))[::-1])]) + return n/d + + def _simplepole(t1, s): + a, k0 = t1['a'], t1['k'] + n = k0 + d = s - a + return n/d + + while len(xm) > 0: + t1 = xm.pop() + i_imagsym = None + i_realsym = None + i_pointsym = None + # The following code checks all remaining poles. If t1 is a pole at + # a+b*I, then we check for a-b*I, -a+b*I, and -a-b*I, and + # assign the respective indices to i_imagsym, i_realsym, i_pointsym. + # -a-b*I / i_pointsym only applies if both a and b are != 0. + for i in range(len(xm)): + real_eq = t1[re] == xm[i][re] + realsym = t1[re] == -xm[i][re] + imag_eq = t1[im] == xm[i][im] + imagsym = t1[im] == -xm[i][im] + if realsym and imagsym and t1[re] != 0 and t1[im] != 0: + i_pointsym = i + elif realsym and imag_eq and t1[re] != 0: + i_realsym = i + elif real_eq and imagsym and t1[im] != 0: + i_imagsym = i + + # The next part looks for four possible pole constellations: + # quad: a+b*I, a-b*I, -a+b*I, -a-b*I + # cc: a+b*I, a-b*I (a may be zero) + # quad: a+b*I, -a+b*I (b may be zero) + # point: a+b*I, -a-b*I (a!=0 and b!=0 is needed, but that has been + # asserted when finding i_pointsym above.) + # If none apply, then t1 is a simple pole. + if ( + i_imagsym is not None and i_realsym is not None + and i_pointsym is not None): + results.append( + _quadpole(t1, + xm[i_imagsym]['k'], xm[i_realsym]['k'], + xm[i_pointsym]['k'], s)) + planes.append(Abs(re(t1['a']))) + # The three additional poles have now been used; to pop them + # easily we have to do it from the back. + indices_to_pop = [i_imagsym, i_realsym, i_pointsym] + indices_to_pop.sort(reverse=True) + for i in indices_to_pop: + xm.pop(i) + elif i_imagsym is not None: + results.append(_ccpole(t1, xm[i_imagsym]['k'], s)) + planes.append(t1[re]) + xm.pop(i_imagsym) + elif i_realsym is not None: + results.append(_rspole(t1, xm[i_realsym]['k'], s)) + planes.append(Abs(t1[re])) + xm.pop(i_realsym) + elif i_pointsym is not None: + results.append(_sypole(t1, xm[i_pointsym]['k'], s)) + planes.append(Abs(t1[re])) + xm.pop(i_pointsym) + else: + results.append(_simplepole(t1, s)) + planes.append(t1[re]) + + return Add(*results), Max(*planes) + + +@DEBUG_WRAP +def _laplace_rule_trig(fn, t_, s): + """ + This rule covers trigonometric factors by splitting everything into a + sum of exponential functions and collecting complex conjugate poles and + real symmetric poles. + """ + t = Dummy('t', real=True) + + if not fn.has(sin, cos, sinh, cosh): + return None + + f, g = _laplace_trig_split(fn.subs(t_, t)) + xm, xn = _laplace_trig_expsum(f, t) + + if len(xn) > 0: + # TODO not implemented yet, but also not important + return None + + if not g.has(t): + r, p = _laplace_trig_ltex(xm, t, s) + return g*r, p, S.true + else: + # Just transform `g` and make frequency-shifted copies + planes = [] + results = [] + G, G_plane, G_cond = _laplace_transform(g, t, s, simplify=False) + for x1 in xm: + results.append(x1['k']*G.subs(s, s-x1['a'])) + planes.append(G_plane+re(x1['a'])) + return Add(*results).subs(t, t_), Max(*planes), G_cond + + +@DEBUG_WRAP +def _laplace_rule_diff(f, t, s): + """ + This function looks for derivatives in the time domain and replaces it + by factors of `s` and initial conditions in the frequency domain. For + example, if it gets ``(diff(f(t), t), t, s)``, it will compute + ``s*LaplaceTransform(f(t), t, s) - f(0)``. + """ + + a = Wild('a', exclude=[t]) + n = Wild('n', exclude=[t]) + g = WildFunction('g') + ma1 = f.match(a*Derivative(g, (t, n))) + if ma1 and ma1[n].is_integer: + m = [z.has(t) for z in ma1[g].args] + if sum(m) == 1: + _debug(' rule: time derivative (4.1.8)') + d = [] + for k in range(ma1[n]): + if k == 0: + y = ma1[g].subs(t, 0) + else: + y = Derivative(ma1[g], (t, k)).subs(t, 0) + d.append(s**(ma1[n]-k-1)*y) + r, pr, cr = _laplace_transform(ma1[g], t, s, simplify=False) + return (ma1[a]*(s**ma1[n]*r - Add(*d)), pr, cr) + return None + + +@DEBUG_WRAP +def _laplace_rule_sdiff(f, t, s): + """ + This function looks for multiplications with polynoimials in `t` as they + correspond to differentiation in the frequency domain. For example, if it + gets ``(t*f(t), t, s)``, it will compute + ``-Derivative(LaplaceTransform(f(t), t, s), s)``. + """ + + if f.is_Mul: + pfac = [1] + ofac = [1] + for fac in Mul.make_args(f): + if fac.is_polynomial(t): + pfac.append(fac) + else: + ofac.append(fac) + if len(pfac) > 1: + pex = prod(pfac) + pc = Poly(pex, t).all_coeffs() + N = len(pc) + if N > 1: + oex = prod(ofac) + r_, p_, c_ = _laplace_transform(oex, t, s, simplify=False) + deri = [r_] + d1 = False + try: + d1 = -diff(deri[-1], s) + except ValueError: + d1 = False + if r_.has(LaplaceTransform): + for k in range(N-1): + deri.append((-1)**(k+1)*Derivative(r_, s, k+1)) + elif d1: + deri.append(d1) + for k in range(N-2): + deri.append(-diff(deri[-1], s)) + if d1: + r = Add(*[pc[N-n-1]*deri[n] for n in range(N)]) + return (r, p_, c_) + # We still have to cover the possibility that there is a symbolic positive + # integer exponent. + n = Wild('n', exclude=[t]) + g = Wild('g') + if ma1 := f.match(t**n*g): + if ma1[n].is_integer and ma1[n].is_positive: + r_, p_, c_ = _laplace_transform(ma1[g], t, s, simplify=False) + return (-1)**ma1[n]*diff(r_, (s, ma1[n])), p_, c_ + return None + + +@DEBUG_WRAP +def _laplace_expand(f, t, s): + """ + This function tries to expand its argument with successively stronger + methods: first it will expand on the top level, then it will expand any + multiplications in depth, then it will try all available expansion methods, + and finally it will try to expand trigonometric functions. + + If it can expand, it will then compute the Laplace transform of the + expanded term. + """ + + r = expand(f, deep=False) + if r.is_Add: + return _laplace_transform(r, t, s, simplify=False) + r = expand_mul(f) + if r.is_Add: + return _laplace_transform(r, t, s, simplify=False) + r = expand(f) + if r.is_Add: + return _laplace_transform(r, t, s, simplify=False) + if r != f: + return _laplace_transform(r, t, s, simplify=False) + r = expand(expand_trig(f)) + if r.is_Add: + return _laplace_transform(r, t, s, simplify=False) + return None + + +@DEBUG_WRAP +def _laplace_apply_prog_rules(f, t, s): + """ + This function applies all program rules and returns the result if one + of them gives a result. + """ + + prog_rules = [_laplace_rule_heaviside, _laplace_rule_delta, + _laplace_rule_timescale, _laplace_rule_exp, + _laplace_rule_trig, + _laplace_rule_diff, _laplace_rule_sdiff] + + for p_rule in prog_rules: + if (L := p_rule(f, t, s)) is not None: + return L + return None + + +@DEBUG_WRAP +def _laplace_apply_simple_rules(f, t, s): + """ + This function applies all simple rules and returns the result if one + of them gives a result. + """ + simple_rules, t_, s_ = _laplace_build_rules() + prep_old = '' + prep_f = '' + for t_dom, s_dom, check, plane, prep in simple_rules: + if prep_old != prep: + prep_f = prep(f.subs({t: t_})) + prep_old = prep + ma = prep_f.match(t_dom) + if ma: + try: + c = check.xreplace(ma) + except TypeError: + # This may happen if the time function has imaginary + # numbers in it. Then we give up. + continue + if c == S.true: + return (s_dom.xreplace(ma).subs({s_: s}), + plane.xreplace(ma), S.true) + return None + + +@DEBUG_WRAP +def _piecewise_to_heaviside(f, t): + """ + This function converts a Piecewise expression to an expression written + with Heaviside. It is not exact, but valid in the context of the Laplace + transform. + """ + if not t.is_real: + r = Dummy('r', real=True) + return _piecewise_to_heaviside(f.xreplace({t: r}), r).xreplace({r: t}) + x = piecewise_exclusive(f) + r = [] + for fn, cond in x.args: + # Here we do not need to do many checks because piecewise_exclusive + # has a clearly predictable output. However, if any of the conditions + # is not relative to t, this function just returns the input argument. + if isinstance(cond, Relational) and t in cond.args: + if isinstance(cond, (Eq, Ne)): + # We do not cover this case; these would be single-point + # exceptions that do not play a role in Laplace practice, + # except if they contain Dirac impulses, and then we can + # expect users to not try to use Piecewise for writing it. + return f + else: + r.append(Heaviside(cond.gts - cond.lts)*fn) + elif isinstance(cond, Or) and len(cond.args) == 2: + # Or(t<2, t>4), Or(t>4, t<=2), ... in any order with any <= >= + for c2 in cond.args: + if c2.lhs == t: + r.append(Heaviside(c2.gts - c2.lts)*fn) + else: + return f + elif isinstance(cond, And) and len(cond.args) == 2: + # And(t>2, t<4), And(t>4, t<=2), ... in any order with any <= >= + c0, c1 = cond.args + if c0.lhs == t and c1.lhs == t: + if '>' in c0.rel_op: + c0, c1 = c1, c0 + r.append( + (Heaviside(c1.gts - c1.lts) - + Heaviside(c0.lts - c0.gts))*fn) + else: + return f + else: + return f + return Add(*r) + + +def laplace_correspondence(f, fdict, /): + """ + This helper function takes a function `f` that is the result of a + ``laplace_transform`` or an ``inverse_laplace_transform``. It replaces all + unevaluated ``LaplaceTransform(y(t), t, s)`` by `Y(s)` for any `s` and + all ``InverseLaplaceTransform(Y(s), s, t)`` by `y(t)` for any `t` if + ``fdict`` contains a correspondence ``{y: Y}``. + + Parameters + ========== + + f : sympy expression + Expression containing unevaluated ``LaplaceTransform`` or + ``LaplaceTransform`` objects. + fdict : dictionary + Dictionary containing one or more function correspondences, + e.g., ``{x: X, y: Y}`` meaning that ``X`` and ``Y`` are the + Laplace transforms of ``x`` and ``y``, respectively. + + Examples + ======== + + >>> from sympy import laplace_transform, diff, Function + >>> from sympy import laplace_correspondence, inverse_laplace_transform + >>> from sympy.abc import t, s + >>> y = Function("y") + >>> Y = Function("Y") + >>> z = Function("z") + >>> Z = Function("Z") + >>> f = laplace_transform(diff(y(t), t, 1) + z(t), t, s, noconds=True) + >>> laplace_correspondence(f, {y: Y, z: Z}) + s*Y(s) + Z(s) - y(0) + >>> f = inverse_laplace_transform(Y(s), s, t) + >>> laplace_correspondence(f, {y: Y}) + y(t) + """ + p = Wild('p') + s = Wild('s') + t = Wild('t') + a = Wild('a') + if ( + not isinstance(f, Expr) + or (not f.has(LaplaceTransform) + and not f.has(InverseLaplaceTransform))): + return f + for y, Y in fdict.items(): + if ( + (m := f.match(LaplaceTransform(y(a), t, s))) is not None + and m[a] == m[t]): + return Y(m[s]) + if ( + (m := f.match(InverseLaplaceTransform(Y(a), s, t, p))) + is not None + and m[a] == m[s]): + return y(m[t]) + func = f.func + args = [laplace_correspondence(arg, fdict) for arg in f.args] + return func(*args) + + +def laplace_initial_conds(f, t, fdict, /): + """ + This helper function takes a function `f` that is the result of a + ``laplace_transform``. It takes an fdict of the form ``{y: [1, 4, 2]}``, + where the values in the list are the initial value, the initial slope, the + initial second derivative, etc., of the function `y(t)`, and replaces all + unevaluated initial conditions. + + Parameters + ========== + + f : sympy expression + Expression containing initial conditions of unevaluated functions. + t : sympy expression + Variable for which the initial conditions are to be applied. + fdict : dictionary + Dictionary containing a list of initial conditions for every + function, e.g., ``{y: [0, 1, 2], x: [3, 4, 5]}``. The order + of derivatives is ascending, so `0`, `1`, `2` are `y(0)`, `y'(0)`, + and `y''(0)`, respectively. + + Examples + ======== + + >>> from sympy import laplace_transform, diff, Function + >>> from sympy import laplace_correspondence, laplace_initial_conds + >>> from sympy.abc import t, s + >>> y = Function("y") + >>> Y = Function("Y") + >>> f = laplace_transform(diff(y(t), t, 3), t, s, noconds=True) + >>> g = laplace_correspondence(f, {y: Y}) + >>> laplace_initial_conds(g, t, {y: [2, 4, 8, 16, 32]}) + s**3*Y(s) - 2*s**2 - 4*s - 8 + """ + for y, ic in fdict.items(): + for k in range(len(ic)): + if k == 0: + f = f.replace(y(0), ic[0]) + elif k == 1: + f = f.replace(Subs(Derivative(y(t), t), t, 0), ic[1]) + else: + f = f.replace(Subs(Derivative(y(t), (t, k)), t, 0), ic[k]) + return f + + +@DEBUG_WRAP +def _laplace_transform(fn, t_, s_, *, simplify): + """ + Front-end function of the Laplace transform. It tries to apply all known + rules recursively, and if everything else fails, it tries to integrate. + """ + + terms_t = Add.make_args(fn) + terms_s = [] + terms = [] + planes = [] + conditions = [] + + for ff in terms_t: + k, ft = ff.as_independent(t_, as_Add=False) + if ft.has(SingularityFunction): + _terms = Add.make_args(ft.rewrite(Heaviside)) + for _term in _terms: + k1, f1 = _term.as_independent(t_, as_Add=False) + terms.append((k*k1, f1)) + elif ft.func == Piecewise and not ft.has(DiracDelta(t_)): + _terms = Add.make_args(_piecewise_to_heaviside(ft, t_)) + for _term in _terms: + k1, f1 = _term.as_independent(t_, as_Add=False) + terms.append((k*k1, f1)) + else: + terms.append((k, ft)) + + for k, ft in terms: + if ft.has(SingularityFunction): + r = (LaplaceTransform(ft, t_, s_), S.NegativeInfinity, True) + else: + if ft.has(Heaviside(t_)) and not ft.has(DiracDelta(t_)): + # For t>=0, Heaviside(t)=1 can be used, except if there is also + # a DiracDelta(t) present, in which case removing Heaviside(t) + # is unnecessary because _laplace_rule_delta can deal with it. + ft = ft.subs(Heaviside(t_), 1) + if ( + (r := _laplace_apply_simple_rules(ft, t_, s_)) + is not None or + (r := _laplace_apply_prog_rules(ft, t_, s_)) + is not None or + (r := _laplace_expand(ft, t_, s_)) is not None): + pass + elif any(undef.has(t_) for undef in ft.atoms(AppliedUndef)): + # If there are undefined functions f(t) then integration is + # unlikely to do anything useful so we skip it and given an + # unevaluated LaplaceTransform. + r = (LaplaceTransform(ft, t_, s_), S.NegativeInfinity, True) + elif (r := _laplace_transform_integration( + ft, t_, s_, simplify=simplify)) is not None: + pass + else: + r = (LaplaceTransform(ft, t_, s_), S.NegativeInfinity, True) + (ri_, pi_, ci_) = r + terms_s.append(k*ri_) + planes.append(pi_) + conditions.append(ci_) + + result = Add(*terms_s) + if simplify: + result = result.simplify(doit=False) + plane = Max(*planes) + condition = And(*conditions) + + return result, plane, condition + + +class LaplaceTransform(IntegralTransform): + """ + Class representing unevaluated Laplace transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute Laplace transforms, see the :func:`laplace_transform` + docstring. + + If this is called with ``.doit()``, it returns the Laplace transform as an + expression. If it is called with ``.doit(noconds=False)``, it returns a + tuple containing the same expression, a convergence plane, and conditions. + """ + + _name = 'Laplace' + + def _compute_transform(self, f, t, s, **hints): + _simplify = hints.get('simplify', False) + LT = _laplace_transform_integration(f, t, s, simplify=_simplify) + return LT + + def _as_integral(self, f, t, s): + return Integral(f*exp(-s*t), (t, S.Zero, S.Infinity)) + + def doit(self, **hints): + """ + Try to evaluate the transform in closed form. + + Explanation + =========== + + Standard hints are the following: + - ``noconds``: if True, do not return convergence conditions. The + default setting is `True`. + - ``simplify``: if True, it simplifies the final result. The + default setting is `False`. + """ + _noconds = hints.get('noconds', True) + _simplify = hints.get('simplify', False) + + debugf('[LT doit] (%s, %s, %s)', (self.function, + self.function_variable, + self.transform_variable)) + + t_ = self.function_variable + s_ = self.transform_variable + fn = self.function + + r = _laplace_transform(fn, t_, s_, simplify=_simplify) + + if _noconds: + return r[0] + else: + return r + + +def laplace_transform(f, t, s, legacy_matrix=True, **hints): + r""" + Compute the Laplace Transform `F(s)` of `f(t)`, + + .. math :: F(s) = \int_{0^{-}}^\infty e^{-st} f(t) \mathrm{d}t. + + Explanation + =========== + + For all sensible functions, this converges absolutely in a + half-plane + + .. math :: a < \operatorname{Re}(s) + + This function returns ``(F, a, cond)`` where ``F`` is the Laplace + transform of ``f``, `a` is the half-plane of convergence, and `cond` are + auxiliary convergence conditions. + + The implementation is rule-based, and if you are interested in which + rules are applied, and whether integration is attempted, you can switch + debug information on by setting ``sympy.SYMPY_DEBUG=True``. The numbers + of the rules in the debug information (and the code) refer to Bateman's + Tables of Integral Transforms [1]. + + The lower bound is `0-`, meaning that this bound should be approached + from the lower side. This is only necessary if distributions are involved. + At present, it is only done if `f(t)` contains ``DiracDelta``, in which + case the Laplace transform is computed implicitly as + + .. math :: + F(s) = \lim_{\tau\to 0^{-}} \int_{\tau}^\infty e^{-st} + f(t) \mathrm{d}t + + by applying rules. + + If the Laplace transform cannot be fully computed in closed form, this + function returns expressions containing unevaluated + :class:`LaplaceTransform` objects. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. If + ``noconds=True``, only `F` will be returned (i.e. not ``cond``, and also + not the plane ``a``). + + .. deprecated:: 1.9 + Legacy behavior for matrices where ``laplace_transform`` with + ``noconds=False`` (the default) returns a Matrix whose elements are + tuples. The behavior of ``laplace_transform`` for matrices will change + in a future release of SymPy to return a tuple of the transformed + Matrix and the convergence conditions for the matrix as a whole. Use + ``legacy_matrix=False`` to enable the new behavior. + + Examples + ======== + + >>> from sympy import DiracDelta, exp, laplace_transform + >>> from sympy.abc import t, s, a + >>> laplace_transform(t**4, t, s) + (24/s**5, 0, True) + >>> laplace_transform(t**a, t, s) + (gamma(a + 1)/(s*s**a), 0, re(a) > -1) + >>> laplace_transform(DiracDelta(t)-a*exp(-a*t), t, s, simplify=True) + (s/(a + s), -re(a), True) + + There are also helper functions that make it easy to solve differential + equations by Laplace transform. For example, to solve + + .. math :: m x''(t) + d x'(t) + k x(t) = 0 + + with initial value `0` and initial derivative `v`: + + >>> from sympy import Function, laplace_correspondence, diff, solve + >>> from sympy import laplace_initial_conds, inverse_laplace_transform + >>> from sympy.abc import d, k, m, v + >>> x = Function('x') + >>> X = Function('X') + >>> f = m*diff(x(t), t, 2) + d*diff(x(t), t) + k*x(t) + >>> F = laplace_transform(f, t, s, noconds=True) + >>> F = laplace_correspondence(F, {x: X}) + >>> F = laplace_initial_conds(F, t, {x: [0, v]}) + >>> F + d*s*X(s) + k*X(s) + m*(s**2*X(s) - v) + >>> Xs = solve(F, X(s))[0] + >>> Xs + m*v/(d*s + k + m*s**2) + >>> inverse_laplace_transform(Xs, s, t) + 2*v*exp(-d*t/(2*m))*sin(t*sqrt((-d**2 + 4*k*m)/m**2)/2)*Heaviside(t)/sqrt((-d**2 + 4*k*m)/m**2) + + References + ========== + + .. [1] Erdelyi, A. (ed.), Tables of Integral Transforms, Volume 1, + Bateman Manuscript Prooject, McGraw-Hill (1954), available: + https://resolver.caltech.edu/CaltechAUTHORS:20140123-101456353 + + See Also + ======== + + inverse_laplace_transform, mellin_transform, fourier_transform + hankel_transform, inverse_hankel_transform + + """ + + _noconds = hints.get('noconds', False) + _simplify = hints.get('simplify', False) + + if isinstance(f, MatrixBase) and hasattr(f, 'applyfunc'): + + conds = not hints.get('noconds', False) + + if conds and legacy_matrix: + adt = 'deprecated-laplace-transform-matrix' + sympy_deprecation_warning( + """ +Calling laplace_transform() on a Matrix with noconds=False (the default) is +deprecated. Either noconds=True or use legacy_matrix=False to get the new +behavior. + """, + deprecated_since_version='1.9', + active_deprecations_target=adt, + ) + # Temporarily disable the deprecation warning for non-Expr objects + # in Matrix + with ignore_warnings(SymPyDeprecationWarning): + return f.applyfunc( + lambda fij: laplace_transform(fij, t, s, **hints)) + else: + elements_trans = [laplace_transform( + fij, t, s, **hints) for fij in f] + if conds: + elements, avals, conditions = zip(*elements_trans) + f_laplace = type(f)(*f.shape, elements) + return f_laplace, Max(*avals), And(*conditions) + else: + return type(f)(*f.shape, elements_trans) + + LT, p, c = LaplaceTransform(f, t, s).doit(noconds=False, + simplify=_simplify) + + if not _noconds: + return LT, p, c + else: + return LT + + +@DEBUG_WRAP +def _inverse_laplace_transform_integration(F, s, t_, plane, *, simplify): + """ The backend function for inverse Laplace transforms. """ + from sympy.integrals.meijerint import meijerint_inversion, _get_coeff_exp + from sympy.integrals.transforms import inverse_mellin_transform + + # There are two strategies we can try: + # 1) Use inverse mellin transform, related by a simple change of variables. + # 2) Use the inversion integral. + + t = Dummy('t', real=True) + + def pw_simp(*args): + """ Simplify a piecewise expression from hyperexpand. """ + if len(args) != 3: + return Piecewise(*args) + arg = args[2].args[0].argument + coeff, exponent = _get_coeff_exp(arg, t) + e1 = args[0].args[0] + e2 = args[1].args[0] + return ( + Heaviside(1/Abs(coeff) - t**exponent)*e1 + + Heaviside(t**exponent - 1/Abs(coeff))*e2) + + if F.is_rational_function(s): + F = F.apart(s) + + if F.is_Add: + f = Add( + *[_inverse_laplace_transform_integration(X, s, t, plane, simplify) + for X in F.args]) + return _simplify(f.subs(t, t_), simplify), True + + try: + f, cond = inverse_mellin_transform(F, s, exp(-t), (None, S.Infinity), + needeval=True, noconds=False) + except IntegralTransformError: + f = None + + if f is None: + f = meijerint_inversion(F, s, t) + if f is None: + return None + if f.is_Piecewise: + f, cond = f.args[0] + if f.has(Integral): + return None + else: + cond = S.true + f = f.replace(Piecewise, pw_simp) + + if f.is_Piecewise: + # many of the functions called below can't work with piecewise + # (b/c it has a bool in args) + return f.subs(t, t_), cond + + u = Dummy('u') + + def simp_heaviside(arg, H0=S.Half): + a = arg.subs(exp(-t), u) + if a.has(t): + return Heaviside(arg, H0) + from sympy.solvers.inequalities import _solve_inequality + rel = _solve_inequality(a > 0, u) + if rel.lts == u: + k = log(rel.gts) + return Heaviside(t + k, H0) + else: + k = log(rel.lts) + return Heaviside(-(t + k), H0) + + f = f.replace(Heaviside, simp_heaviside) + + def simp_exp(arg): + return expand_complex(exp(arg)) + + f = f.replace(exp, simp_exp) + + return _simplify(f.subs(t, t_), simplify), cond + + +@DEBUG_WRAP +def _complete_the_square_in_denom(f, s): + from sympy.simplify.radsimp import fraction + [n, d] = fraction(f) + if d.is_polynomial(s): + cf = d.as_poly(s).all_coeffs() + if len(cf) == 3: + a, b, c = cf + d = a*((s+b/(2*a))**2+c/a-(b/(2*a))**2) + return n/d + + +@cacheit +def _inverse_laplace_build_rules(): + """ + This is an internal helper function that returns the table of inverse + Laplace transform rules in terms of the time variable `t` and the + frequency variable `s`. It is used by `_inverse_laplace_apply_rules`. + """ + s = Dummy('s') + t = Dummy('t') + a = Wild('a', exclude=[s]) + b = Wild('b', exclude=[s]) + c = Wild('c', exclude=[s]) + + _debug('_inverse_laplace_build_rules is building rules') + + def _frac(f, s): + try: + return f.factor(s) + except PolynomialError: + return f + + def same(f): return f + # This list is sorted according to the prep function needed. + _ILT_rules = [ + (a/s, a, S.true, same, 1), + ( + b*(s+a)**(-c), t**(c-1)*exp(-a*t)/gamma(c), + S.true, same, 1), + (1/(s**2+a**2)**2, (sin(a*t) - a*t*cos(a*t))/(2*a**3), + S.true, same, 1), + # The next two rules must be there in that order. For the second + # one, the condition would be a != 0 or, respectively, to take the + # limit a -> 0 after the transform if a == 0. It is much simpler if + # the case a == 0 has its own rule. + (1/(s**b), t**(b - 1)/gamma(b), S.true, same, 1), + (1/(s*(s+a)**b), lowergamma(b, a*t)/(a**b*gamma(b)), + S.true, same, 1) + ] + return _ILT_rules, s, t + + +@DEBUG_WRAP +def _inverse_laplace_apply_simple_rules(f, s, t): + """ + Helper function for the class InverseLaplaceTransform. + """ + if f == 1: + _debug(' rule: 1 o---o DiracDelta()') + return DiracDelta(t), S.true + + _ILT_rules, s_, t_ = _inverse_laplace_build_rules() + _prep = '' + fsubs = f.subs({s: s_}) + + for s_dom, t_dom, check, prep, fac in _ILT_rules: + if _prep != (prep, fac): + _F = prep(fsubs*fac) + _prep = (prep, fac) + ma = _F.match(s_dom) + if ma: + c = check + if c is not S.true: + args = [x.xreplace(ma) for x in c[0]] + c = c[1](*args) + if c == S.true: + return Heaviside(t)*t_dom.xreplace(ma).subs({t_: t}), S.true + + return None + + +@DEBUG_WRAP +def _inverse_laplace_diff(f, s, t, plane): + """ + Helper function for the class InverseLaplaceTransform. + """ + a = Wild('a', exclude=[s]) + n = Wild('n', exclude=[s]) + g = Wild('g') + ma = f.match(a*Derivative(g, (s, n))) + if ma and ma[n].is_integer: + _debug(' rule: t**n*f(t) o---o (-1)**n*diff(F(s), s, n)') + r, c = _inverse_laplace_transform( + ma[g], s, t, plane, simplify=False, dorational=False) + return (-t)**ma[n]*r, c + return None + + +@DEBUG_WRAP +def _inverse_laplace_time_shift(F, s, t, plane): + """ + Helper function for the class InverseLaplaceTransform. + """ + a = Wild('a', exclude=[s]) + g = Wild('g') + + if not F.has(s): + return F*DiracDelta(t), S.true + if not F.has(exp): + return None + + ma1 = F.match(exp(a*s)) + if ma1: + if ma1[a].is_negative: + _debug(' rule: exp(-a*s) o---o DiracDelta(t-a)') + return DiracDelta(t+ma1[a]), S.true + else: + return InverseLaplaceTransform(F, s, t, plane), S.true + + ma1 = F.match(exp(a*s)*g) + if ma1: + if ma1[a].is_negative: + _debug(' rule: exp(-a*s)*F(s) o---o Heaviside(t-a)*f(t-a)') + return _inverse_laplace_transform( + ma1[g], s, t+ma1[a], plane, simplify=False, dorational=True) + else: + return InverseLaplaceTransform(F, s, t, plane), S.true + return None + + +@DEBUG_WRAP +def _inverse_laplace_freq_shift(F, s, t, plane): + """ + Helper function for the class InverseLaplaceTransform. + """ + if not F.has(s): + return F*DiracDelta(t), S.true + if len(args := F.args) == 1: + a = Wild('a', exclude=[s]) + if (ma := args[0].match(s-a)) and re(ma[a]).is_positive: + _debug(' rule: F(s-a) o---o exp(-a*t)*f(t)') + return ( + exp(-ma[a]*t) * + InverseLaplaceTransform(F.func(s), s, t, plane), S.true) + return None + + +@DEBUG_WRAP +def _inverse_laplace_time_diff(F, s, t, plane): + """ + Helper function for the class InverseLaplaceTransform. + """ + n = Wild('n', exclude=[s]) + g = Wild('g') + + ma1 = F.match(s**n*g) + if ma1 and ma1[n].is_integer and ma1[n].is_positive: + _debug(' rule: s**n*F(s) o---o diff(f(t), t, n)') + r, c = _inverse_laplace_transform( + ma1[g], s, t, plane, simplify=False, dorational=True) + r = r.replace(Heaviside(t), 1) + if r.has(InverseLaplaceTransform): + return diff(r, t, ma1[n]), c + else: + return Heaviside(t)*diff(r, t, ma1[n]), c + return None + + +@DEBUG_WRAP +def _inverse_laplace_irrational(fn, s, t, plane): + """ + Helper function for the class InverseLaplaceTransform. + """ + + a = Wild('a', exclude=[s]) + b = Wild('b', exclude=[s]) + m = Wild('m', exclude=[s]) + n = Wild('n', exclude=[s]) + + result = None + condition = S.true + + fa = fn.as_ordered_factors() + + ma = [x.match((a*s**m+b)**n) for x in fa] + + if None in ma: + return None + + constants = S.One + zeros = [] + poles = [] + rest = [] + + for term in ma: + if term[a] == 0: + constants = constants*term + elif term[n].is_positive: + zeros.append(term) + elif term[n].is_negative: + poles.append(term) + else: + rest.append(term) + + # The code below assumes that the poles are sorted in a specific way: + poles = sorted(poles, key=lambda x: (x[n], x[b] != 0, x[b])) + zeros = sorted(zeros, key=lambda x: (x[n], x[b] != 0, x[b])) + + if len(rest) != 0: + return None + + if len(poles) == 1 and len(zeros) == 0: + if poles[0][n] == -1 and poles[0][m] == S.Half: + # 1/(a0*sqrt(s)+b0) == 1/a0 * 1/(sqrt(s)+b0/a0) + a_ = poles[0][b]/poles[0][a] + k_ = 1/poles[0][a]*constants + if a_.is_positive: + result = ( + k_/sqrt(pi)/sqrt(t) - + k_*a_*exp(a_**2*t)*erfc(a_*sqrt(t))) + _debug(' rule 5.3.4') + elif poles[0][n] == -2 and poles[0][m] == S.Half: + # 1/(a0*sqrt(s)+b0)**2 == 1/a0**2 * 1/(sqrt(s)+b0/a0)**2 + a_sq = poles[0][b]/poles[0][a] + a_ = a_sq**2 + k_ = 1/poles[0][a]**2*constants + if a_sq.is_positive: + result = ( + k_*(1 - 2/sqrt(pi)*sqrt(a_)*sqrt(t) + + (1-2*a_*t)*exp(a_*t)*(erf(sqrt(a_)*sqrt(t))-1))) + _debug(' rule 5.3.10') + elif poles[0][n] == -3 and poles[0][m] == S.Half: + # 1/(a0*sqrt(s)+b0)**3 == 1/a0**3 * 1/(sqrt(s)+b0/a0)**3 + a_ = poles[0][b]/poles[0][a] + k_ = 1/poles[0][a]**3*constants + if a_.is_positive: + result = ( + k_*(2/sqrt(pi)*(a_**2*t+1)*sqrt(t) - + a_*t*exp(a_**2*t)*(2*a_**2*t+3)*erfc(a_*sqrt(t)))) + _debug(' rule 5.3.13') + elif poles[0][n] == -4 and poles[0][m] == S.Half: + # 1/(a0*sqrt(s)+b0)**4 == 1/a0**4 * 1/(sqrt(s)+b0/a0)**4 + a_ = poles[0][b]/poles[0][a] + k_ = 1/poles[0][a]**4*constants/3 + if a_.is_positive: + result = ( + k_*(t*(4*a_**4*t**2+12*a_**2*t+3)*exp(a_**2*t) * + erfc(a_*sqrt(t)) - + 2/sqrt(pi)*a_**3*t**(S(5)/2)*(2*a_**2*t+5))) + _debug(' rule 5.3.16') + elif poles[0][n] == -S.Half and poles[0][m] == 2: + # 1/sqrt(a0*s**2+b0) == 1/sqrt(a0) * 1/sqrt(s**2+b0/a0) + a_ = sqrt(poles[0][b]/poles[0][a]) + k_ = 1/sqrt(poles[0][a])*constants + result = (k_*(besselj(0, a_*t))) + _debug(' rule 5.3.35/44') + + elif len(poles) == 1 and len(zeros) == 1: + if ( + poles[0][n] == -3 and poles[0][m] == S.Half and + zeros[0][n] == S.Half and zeros[0][b] == 0): + # sqrt(az*s)/(ap*sqrt(s+bp)**3) + # == sqrt(az)/ap * sqrt(s)/(sqrt(s+bp)**3) + a_ = poles[0][b] + k_ = sqrt(zeros[0][a])/poles[0][a]*constants + result = ( + k_*(2*a_**4*t**2+5*a_**2*t+1)*exp(a_**2*t) * + erfc(a_*sqrt(t)) - 2/sqrt(pi)*a_*(a_**2*t+2)*sqrt(t)) + _debug(' rule 5.3.14') + if ( + poles[0][n] == -1 and poles[0][m] == 1 and + zeros[0][n] == S.Half and zeros[0][m] == 1): + # sqrt(az*s+bz)/(ap*s+bp) + # == sqrt(az)/ap * (sqrt(s+bz/az)/(s+bp/ap)) + a_ = zeros[0][b]/zeros[0][a] + b_ = poles[0][b]/poles[0][a] + k_ = sqrt(zeros[0][a])/poles[0][a]*constants + result = ( + k_*(exp(-a_*t)/sqrt(t)/sqrt(pi)+sqrt(a_-b_) * + exp(-b_*t)*erf(sqrt(a_-b_)*sqrt(t)))) + _debug(' rule 5.3.22') + + elif len(poles) == 2 and len(zeros) == 0: + if ( + poles[0][n] == -1 and poles[0][m] == 1 and + poles[1][n] == -S.Half and poles[1][m] == 1 and + poles[1][b] == 0): + # 1/((a0*s+b0)*sqrt(a1*s)) + # == 1/(a0*sqrt(a1)) * 1/((s+b0/a0)*sqrt(s)) + a_ = -poles[0][b]/poles[0][a] + k_ = 1/sqrt(poles[1][a])/poles[0][a]*constants + if a_.is_positive: + result = (k_/sqrt(a_)*exp(a_*t)*erf(sqrt(a_)*sqrt(t))) + _debug(' rule 5.3.1') + elif ( + poles[0][n] == -1 and poles[0][m] == 1 and poles[0][b] == 0 and + poles[1][n] == -1 and poles[1][m] == S.Half): + # 1/(a0*s*(a1*sqrt(s)+b1)) + # == 1/(a0*a1) * 1/(s*(sqrt(s)+b1/a1)) + a_ = poles[1][b]/poles[1][a] + k_ = 1/poles[0][a]/poles[1][a]/a_*constants + if a_.is_positive: + result = k_*(1-exp(a_**2*t)*erfc(a_*sqrt(t))) + _debug(' rule 5.3.5') + elif ( + poles[0][n] == -1 and poles[0][m] == S.Half and + poles[1][n] == -S.Half and poles[1][m] == 1 and + poles[1][b] == 0): + # 1/((a0*sqrt(s)+b0)*(sqrt(a1*s)) + # == 1/(a0*sqrt(a1)) * 1/((sqrt(s)+b0/a0)"sqrt(s)) + a_ = poles[0][b]/poles[0][a] + k_ = 1/(poles[0][a]*sqrt(poles[1][a]))*constants + if a_.is_positive: + result = k_*exp(a_**2*t)*erfc(a_*sqrt(t)) + _debug(' rule 5.3.7') + elif ( + poles[0][n] == -S(3)/2 and poles[0][m] == 1 and + poles[0][b] == 0 and poles[1][n] == -1 and + poles[1][m] == S.Half): + # 1/((a0**(3/2)*s**(3/2))*(a1*sqrt(s)+b1)) + # == 1/(a0**(3/2)*a1) 1/((s**(3/2))*(sqrt(s)+b1/a1)) + # Note that Bateman54 5.3 (8) is incorrect; there (sqrt(p)+a) + # should be (sqrt(p)+a)**(-1). + a_ = poles[1][b]/poles[1][a] + k_ = 1/(poles[0][a]**(S(3)/2)*poles[1][a])/a_**2*constants + if a_.is_positive: + result = ( + k_*(2/sqrt(pi)*a_*sqrt(t)+exp(a_**2*t)*erfc(a_*sqrt(t))-1)) + _debug(' rule 5.3.8') + elif ( + poles[0][n] == -2 and poles[0][m] == S.Half and + poles[1][n] == -1 and poles[1][m] == 1 and + poles[1][b] == 0): + # 1/((a0*sqrt(s)+b0)**2*a1*s) + # == 1/a0**2/a1 * 1/(sqrt(s)+b0/a0)**2/s + a_sq = poles[0][b]/poles[0][a] + a_ = a_sq**2 + k_ = 1/poles[0][a]**2/poles[1][a]*constants + if a_sq.is_positive: + result = ( + k_*(1/a_ + (2*t-1/a_)*exp(a_*t)*erfc(sqrt(a_)*sqrt(t)) - + 2/sqrt(pi)/sqrt(a_)*sqrt(t))) + _debug(' rule 5.3.11') + elif ( + poles[0][n] == -2 and poles[0][m] == S.Half and + poles[1][n] == -S.Half and poles[1][m] == 1 and + poles[1][b] == 0): + # 1/((a0*sqrt(s)+b0)**2*sqrt(a1*s)) + # == 1/a0**2/sqrt(a1) * 1/(sqrt(s)+b0/a0)**2/sqrt(s) + a_ = poles[0][b]/poles[0][a] + k_ = 1/poles[0][a]**2/sqrt(poles[1][a])*constants + if a_.is_positive: + result = ( + k_*(2/sqrt(pi)*sqrt(t) - + 2*a_*t*exp(a_**2*t)*erfc(a_*sqrt(t)))) + _debug(' rule 5.3.12') + elif ( + poles[0][n] == -3 and poles[0][m] == S.Half and + poles[1][n] == -S.Half and poles[1][m] == 1 and + poles[1][b] == 0): + # 1 / (sqrt(a1*s)*(a0*sqrt(s+b0)**3)) + # == 1/(sqrt(a1)*a0) * 1/(sqrt(s)*(sqrt(s+b0)**3)) + a_ = poles[0][b] + k_ = constants/sqrt(poles[1][a])/poles[0][a] + result = k_*( + (2*a_**2*t+1)*t*exp(a_**2*t)*erfc(a_*sqrt(t)) - + 2/sqrt(pi)*a_*t**(S(3)/2)) + _debug(' rule 5.3.15') + elif ( + poles[0][n] == -1 and poles[0][m] == 1 and + poles[1][n] == -S.Half and poles[1][m] == 1): + # 1 / ( (a0*s+b0)* sqrt(a1*s+b1) ) + # == 1/(sqrt(a1)*a0) * 1 / ( (s+b0/a0)* sqrt(s+b1/a1) ) + a_ = poles[0][b]/poles[0][a] + b_ = poles[1][b]/poles[1][a] + k_ = constants/sqrt(poles[1][a])/poles[0][a] + result = k_*( + 1/sqrt(b_-a_)*exp(-a_*t)*erf(sqrt(b_-a_)*sqrt(t))) + _debug(' rule 5.3.23') + + elif len(poles) == 2 and len(zeros) == 1: + if ( + poles[0][n] == -1 and poles[0][m] == 1 and + poles[1][n] == -1 and poles[1][m] == S.Half and + zeros[0][n] == S.Half and zeros[0][m] == 1 and + zeros[0][b] == 0): + # sqrt(za0*s)/((a0*s+b0)*(a1*sqrt(s)+b1)) + # == sqrt(za0)/(a0*a1) * s/((s+b0/a0)*(sqrt(s)+b1/a1)) + a_sq = poles[1][b]/poles[1][a] + a_ = a_sq**2 + b_ = -poles[0][b]/poles[0][a] + k_ = sqrt(zeros[0][a])/poles[0][a]/poles[1][a]/(a_-b_)*constants + if a_sq.is_positive and b_.is_positive: + result = k_*( + a_*exp(a_*t)*erfc(sqrt(a_)*sqrt(t)) + + sqrt(a_)*sqrt(b_)*exp(b_*t)*erfc(sqrt(b_)*sqrt(t)) - + b_*exp(b_*t)) + _debug(' rule 5.3.6') + elif ( + poles[0][n] == -1 and poles[0][m] == 1 and + poles[0][b] == 0 and poles[1][n] == -1 and + poles[1][m] == S.Half and zeros[0][n] == 1 and + zeros[0][m] == S.Half): + # (az*sqrt(s)+bz)/(a0*s*(a1*sqrt(s)+b1)) + # == az/a0/a1 * (sqrt(z)+bz/az)/(s*(sqrt(s)+b1/a1)) + a_num = zeros[0][b]/zeros[0][a] + a_ = poles[1][b]/poles[1][a] + if a_+a_num == 0: + k_ = zeros[0][a]/poles[0][a]/poles[1][a]*constants + result = k_*( + 2*exp(a_**2*t)*erfc(a_*sqrt(t))-1) + _debug(' rule 5.3.17') + elif ( + poles[1][n] == -1 and poles[1][m] == 1 and + poles[1][b] == 0 and poles[0][n] == -2 and + poles[0][m] == S.Half and zeros[0][n] == 2 and + zeros[0][m] == S.Half): + # (az*sqrt(s)+bz)**2/(a1*s*(a0*sqrt(s)+b0)**2) + # == az**2/a1/a0**2 * (sqrt(z)+bz/az)**2/(s*(sqrt(s)+b0/a0)**2) + a_num = zeros[0][b]/zeros[0][a] + a_ = poles[0][b]/poles[0][a] + if a_+a_num == 0: + k_ = zeros[0][a]**2/poles[1][a]/poles[0][a]**2*constants + result = k_*( + 1 + 8*a_**2*t*exp(a_**2*t)*erfc(a_*sqrt(t)) - + 8/sqrt(pi)*a_*sqrt(t)) + _debug(' rule 5.3.18') + elif ( + poles[1][n] == -1 and poles[1][m] == 1 and + poles[1][b] == 0 and poles[0][n] == -3 and + poles[0][m] == S.Half and zeros[0][n] == 3 and + zeros[0][m] == S.Half): + # (az*sqrt(s)+bz)**3/(a1*s*(a0*sqrt(s)+b0)**3) + # == az**3/a1/a0**3 * (sqrt(z)+bz/az)**3/(s*(sqrt(s)+b0/a0)**3) + a_num = zeros[0][b]/zeros[0][a] + a_ = poles[0][b]/poles[0][a] + if a_+a_num == 0: + k_ = zeros[0][a]**3/poles[1][a]/poles[0][a]**3*constants + result = k_*( + 2*(8*a_**4*t**2+8*a_**2*t+1)*exp(a_**2*t) * + erfc(a_*sqrt(t))-8/sqrt(pi)*a_*sqrt(t)*(2*a_**2*t+1)-1) + _debug(' rule 5.3.19') + + elif len(poles) == 3 and len(zeros) == 0: + if ( + poles[0][n] == -1 and poles[0][b] == 0 and poles[0][m] == 1 and + poles[1][n] == -1 and poles[1][m] == 1 and + poles[2][n] == -S.Half and poles[2][m] == 1): + # 1/((a0*s)*(a1*s+b1)*sqrt(a2*s)) + # == 1/(a0*a1*sqrt(a2)) * 1/((s)*(s+b1/a1)*sqrt(s)) + a_ = -poles[1][b]/poles[1][a] + k_ = 1/poles[0][a]/poles[1][a]/sqrt(poles[2][a])*constants + if a_.is_positive: + result = k_ * ( + a_**(-S(3)/2) * exp(a_*t) * erf(sqrt(a_)*sqrt(t)) - + 2/a_/sqrt(pi)*sqrt(t)) + _debug(' rule 5.3.2') + elif ( + poles[0][n] == -1 and poles[0][m] == 1 and + poles[1][n] == -1 and poles[1][m] == S.Half and + poles[2][n] == -S.Half and poles[2][m] == 1 and + poles[2][b] == 0): + # 1/((a0*s+b0)*(a1*sqrt(s)+b1)*(sqrt(a2)*sqrt(s))) + # == 1/(a0*a1*sqrt(a2)) * 1/((s+b0/a0)*(sqrt(s)+b1/a1)*sqrt(s)) + a_sq = poles[1][b]/poles[1][a] + a_ = a_sq**2 + b_ = -poles[0][b]/poles[0][a] + k_ = ( + 1/poles[0][a]/poles[1][a]/sqrt(poles[2][a]) / + (sqrt(b_)*(a_-b_))) + if a_sq.is_positive and b_.is_positive: + result = k_ * ( + sqrt(b_)*exp(a_*t)*erfc(sqrt(a_)*sqrt(t)) + + sqrt(a_)*exp(b_*t)*erf(sqrt(b_)*sqrt(t)) - + sqrt(b_)*exp(b_*t)) + _debug(' rule 5.3.9') + + if result is None: + return None + else: + return Heaviside(t)*result, condition + + +@DEBUG_WRAP +def _inverse_laplace_early_prog_rules(F, s, t, plane): + """ + Helper function for the class InverseLaplaceTransform. + """ + prog_rules = [_inverse_laplace_irrational] + + for p_rule in prog_rules: + if (r := p_rule(F, s, t, plane)) is not None: + return r + return None + + +@DEBUG_WRAP +def _inverse_laplace_apply_prog_rules(F, s, t, plane): + """ + Helper function for the class InverseLaplaceTransform. + """ + prog_rules = [_inverse_laplace_time_shift, _inverse_laplace_freq_shift, + _inverse_laplace_time_diff, _inverse_laplace_diff, + _inverse_laplace_irrational] + + for p_rule in prog_rules: + if (r := p_rule(F, s, t, plane)) is not None: + return r + return None + + +@DEBUG_WRAP +def _inverse_laplace_expand(fn, s, t, plane): + """ + Helper function for the class InverseLaplaceTransform. + """ + if fn.is_Add: + return None + r = expand(fn, deep=False) + if r.is_Add: + return _inverse_laplace_transform( + r, s, t, plane, simplify=False, dorational=True) + r = expand_mul(fn) + if r.is_Add: + return _inverse_laplace_transform( + r, s, t, plane, simplify=False, dorational=True) + r = expand(fn) + if r.is_Add: + return _inverse_laplace_transform( + r, s, t, plane, simplify=False, dorational=True) + if fn.is_rational_function(s): + r = fn.apart(s).doit() + if r.is_Add: + return _inverse_laplace_transform( + r, s, t, plane, simplify=False, dorational=True) + return None + + +@DEBUG_WRAP +def _inverse_laplace_rational(fn, s, t, plane, *, simplify): + """ + Helper function for the class InverseLaplaceTransform. + """ + x_ = symbols('x_') + f = fn.apart(s) + terms = Add.make_args(f) + terms_t = [] + conditions = [S.true] + for term in terms: + [n, d] = term.as_numer_denom() + dc = d.as_poly(s).all_coeffs() + dc_lead = dc[0] + dc = [x/dc_lead for x in dc] + nc = [x/dc_lead for x in n.as_poly(s).all_coeffs()] + if len(dc) == 1: + N = len(nc)-1 + for c in enumerate(nc): + r = c[1]*DiracDelta(t, N-c[0]) + terms_t.append(r) + elif len(dc) == 2: + r = nc[0]*exp(-dc[1]*t) + terms_t.append(Heaviside(t)*r) + elif len(dc) == 3: + a = dc[1]/2 + b = (dc[2]-a**2).factor() + if len(nc) == 1: + nc = [S.Zero] + nc + l, m = tuple(nc) + if b == 0: + r = (m*t+l*(1-a*t))*exp(-a*t) + else: + hyp = False + if b.is_negative: + b = -b + hyp = True + b2 = list(roots(x_**2-b, x_).keys())[0] + bs = sqrt(b).simplify() + if hyp: + r = ( + l*exp(-a*t)*cosh(b2*t) + (m-a*l) / + bs*exp(-a*t)*sinh(bs*t)) + else: + r = l*exp(-a*t)*cos(b2*t) + (m-a*l)/bs*exp(-a*t)*sin(bs*t) + terms_t.append(Heaviside(t)*r) + else: + ft, cond = _inverse_laplace_transform( + term, s, t, plane, simplify=simplify, dorational=False) + terms_t.append(ft) + conditions.append(cond) + + result = Add(*terms_t) + if simplify: + result = result.simplify(doit=False) + return result, And(*conditions) + + +@DEBUG_WRAP +def _inverse_laplace_transform(fn, s_, t_, plane, *, simplify, dorational): + """ + Front-end function of the inverse Laplace transform. It tries to apply all + known rules recursively. If everything else fails, it tries to integrate. + """ + terms = Add.make_args(fn) + terms_t = [] + conditions = [] + + for term in terms: + if term.has(exp): + # Simplify expressions with exp() such that time-shifted + # expressions have negative exponents in the numerator instead of + # positive exponents in the numerator and denominator; this is a + # (necessary) trick. It will, for example, convert + # (s**2*exp(2*s) + 4*exp(s) - 4)*exp(-2*s)/(s*(s**2 + 1)) into + # (s**2 + 4*exp(-s) - 4*exp(-2*s))/(s*(s**2 + 1)) + term = term.subs(s_, -s_).together().subs(s_, -s_) + k, f = term.as_independent(s_, as_Add=False) + if ( + dorational and term.is_rational_function(s_) and + (r := _inverse_laplace_rational( + f, s_, t_, plane, simplify=simplify)) + is not None or + (r := _inverse_laplace_apply_simple_rules(f, s_, t_)) + is not None or + (r := _inverse_laplace_early_prog_rules(f, s_, t_, plane)) + is not None or + (r := _inverse_laplace_expand(f, s_, t_, plane)) + is not None or + (r := _inverse_laplace_apply_prog_rules(f, s_, t_, plane)) + is not None): + pass + elif any(undef.has(s_) for undef in f.atoms(AppliedUndef)): + # If there are undefined functions f(t) then integration is + # unlikely to do anything useful so we skip it and given an + # unevaluated LaplaceTransform. + r = (InverseLaplaceTransform(f, s_, t_, plane), S.true) + elif ( + r := _inverse_laplace_transform_integration( + f, s_, t_, plane, simplify=simplify)) is not None: + pass + else: + r = (InverseLaplaceTransform(f, s_, t_, plane), S.true) + (ri_, ci_) = r + terms_t.append(k*ri_) + conditions.append(ci_) + + result = Add(*terms_t) + if simplify: + result = result.simplify(doit=False) + condition = And(*conditions) + + return result, condition + + +class InverseLaplaceTransform(IntegralTransform): + """ + Class representing unevaluated inverse Laplace transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute inverse Laplace transforms, see the + :func:`inverse_laplace_transform` docstring. + """ + + _name = 'Inverse Laplace' + _none_sentinel = Dummy('None') + _c = Dummy('c') + + def __new__(cls, F, s, x, plane, **opts): + if plane is None: + plane = InverseLaplaceTransform._none_sentinel + return IntegralTransform.__new__(cls, F, s, x, plane, **opts) + + @property + def fundamental_plane(self): + plane = self.args[3] + if plane is InverseLaplaceTransform._none_sentinel: + plane = None + return plane + + def _compute_transform(self, F, s, t, **hints): + return _inverse_laplace_transform_integration( + F, s, t, self.fundamental_plane, **hints) + + def _as_integral(self, F, s, t): + c = self.__class__._c + return ( + Integral(exp(s*t)*F, (s, c - S.ImaginaryUnit*S.Infinity, + c + S.ImaginaryUnit*S.Infinity)) / + (2*S.Pi*S.ImaginaryUnit)) + + def doit(self, **hints): + """ + Try to evaluate the transform in closed form. + + Explanation + =========== + + Standard hints are the following: + - ``noconds``: if True, do not return convergence conditions. The + default setting is `True`. + - ``simplify``: if True, it simplifies the final result. The + default setting is `False`. + """ + _noconds = hints.get('noconds', True) + _simplify = hints.get('simplify', False) + + debugf('[ILT doit] (%s, %s, %s)', (self.function, + self.function_variable, + self.transform_variable)) + + s_ = self.function_variable + t_ = self.transform_variable + fn = self.function + plane = self.fundamental_plane + + r = _inverse_laplace_transform( + fn, s_, t_, plane, simplify=_simplify, dorational=True) + + if _noconds: + return r[0] + else: + return r + + +def inverse_laplace_transform(F, s, t, plane=None, **hints): + r""" + Compute the inverse Laplace transform of `F(s)`, defined as + + .. math :: + f(t) = \frac{1}{2\pi i} \int_{c-i\infty}^{c+i\infty} e^{st} + F(s) \mathrm{d}s, + + for `c` so large that `F(s)` has no singularites in the + half-plane `\operatorname{Re}(s) > c-\epsilon`. + + Explanation + =========== + + The plane can be specified by + argument ``plane``, but will be inferred if passed as None. + + Under certain regularity conditions, this recovers `f(t)` from its + Laplace Transform `F(s)`, for non-negative `t`, and vice + versa. + + If the integral cannot be computed in closed form, this function returns + an unevaluated :class:`InverseLaplaceTransform` object. + + Note that this function will always assume `t` to be real, + regardless of the SymPy assumption on `t`. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + + Examples + ======== + + >>> from sympy import inverse_laplace_transform, exp, Symbol + >>> from sympy.abc import s, t + >>> a = Symbol('a', positive=True) + >>> inverse_laplace_transform(exp(-a*s)/s, s, t) + Heaviside(-a + t) + + See Also + ======== + + laplace_transform + hankel_transform, inverse_hankel_transform + """ + _noconds = hints.get('noconds', True) + _simplify = hints.get('simplify', False) + + if isinstance(F, MatrixBase) and hasattr(F, 'applyfunc'): + return F.applyfunc( + lambda Fij: inverse_laplace_transform(Fij, s, t, plane, **hints)) + + r, c = InverseLaplaceTransform(F, s, t, plane).doit( + noconds=False, simplify=_simplify) + + if _noconds: + return r + else: + return r, c + + +def _fast_inverse_laplace(e, s, t): + """Fast inverse Laplace transform of rational function including RootSum""" + a, b, n = symbols('a, b, n', cls=Wild, exclude=[s]) + + def _ilt(e): + if not e.has(s): + return e + elif e.is_Add: + return _ilt_add(e) + elif e.is_Mul: + return _ilt_mul(e) + elif e.is_Pow: + return _ilt_pow(e) + elif isinstance(e, RootSum): + return _ilt_rootsum(e) + else: + raise NotImplementedError + + def _ilt_add(e): + return e.func(*map(_ilt, e.args)) + + def _ilt_mul(e): + coeff, expr = e.as_independent(s) + if expr.is_Mul: + raise NotImplementedError + return coeff * _ilt(expr) + + def _ilt_pow(e): + match = e.match((a*s + b)**n) + if match is not None: + nm, am, bm = match[n], match[a], match[b] + if nm.is_Integer and nm < 0: + return t**(-nm-1)*exp(-(bm/am)*t)/(am**-nm*gamma(-nm)) + if nm == 1: + return exp(-(bm/am)*t) / am + raise NotImplementedError + + def _ilt_rootsum(e): + expr = e.fun.expr + [variable] = e.fun.variables + return RootSum(e.poly, Lambda(variable, together(_ilt(expr)))) + + return _ilt(e) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/manualintegrate.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/manualintegrate.py new file mode 100644 index 0000000000000000000000000000000000000000..2908fb33003ba9c22da47e550edcfea2b41a26a0 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/manualintegrate.py @@ -0,0 +1,2174 @@ +"""Integration method that emulates by-hand techniques. + +This module also provides functionality to get the steps used to evaluate a +particular integral, in the ``integral_steps`` function. This will return +nested ``Rule`` s representing the integration rules used. + +Each ``Rule`` class represents a (maybe parametrized) integration rule, e.g. +``SinRule`` for integrating ``sin(x)`` and ``ReciprocalSqrtQuadraticRule`` +for integrating ``1/sqrt(a+b*x+c*x**2)``. The ``eval`` method returns the +integration result. + +The ``manualintegrate`` function computes the integral by calling ``eval`` +on the rule returned by ``integral_steps``. + +The integrator can be extended with new heuristics and evaluation +techniques. To do so, extend the ``Rule`` class, implement ``eval`` method, +then write a function that accepts an ``IntegralInfo`` object and returns +either a ``Rule`` instance or ``None``. If the new technique requires a new +match, add the key and call to the antiderivative function to integral_steps. +To enable simple substitutions, add the match to find_substitutions. + +""" + +from __future__ import annotations +from typing import NamedTuple, Type, Callable, Sequence +from abc import ABC, abstractmethod +from dataclasses import dataclass +from collections import defaultdict +from collections.abc import Mapping + +from sympy.core.add import Add +from sympy.core.cache import cacheit +from sympy.core.containers import Dict +from sympy.core.expr import Expr +from sympy.core.function import Derivative +from sympy.core.logic import fuzzy_not +from sympy.core.mul import Mul +from sympy.core.numbers import Integer, Number, E +from sympy.core.power import Pow +from sympy.core.relational import Eq, Ne, Boolean +from sympy.core.singleton import S +from sympy.core.symbol import Dummy, Symbol, Wild +from sympy.functions.elementary.complexes import Abs +from sympy.functions.elementary.exponential import exp, log +from sympy.functions.elementary.hyperbolic import (HyperbolicFunction, csch, + cosh, coth, sech, sinh, tanh, asinh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import (TrigonometricFunction, + cos, sin, tan, cot, csc, sec, acos, asin, atan, acot, acsc, asec) +from sympy.functions.special.delta_functions import Heaviside, DiracDelta +from sympy.functions.special.error_functions import (erf, erfi, fresnelc, + fresnels, Ci, Chi, Si, Shi, Ei, li) +from sympy.functions.special.gamma_functions import uppergamma +from sympy.functions.special.elliptic_integrals import elliptic_e, elliptic_f +from sympy.functions.special.polynomials import (chebyshevt, chebyshevu, + legendre, hermite, laguerre, assoc_laguerre, gegenbauer, jacobi, + OrthogonalPolynomial) +from sympy.functions.special.zeta_functions import polylog +from .integrals import Integral +from sympy.logic.boolalg import And +from sympy.ntheory.factor_ import primefactors +from sympy.polys.polytools import degree, lcm_list, gcd_list, Poly +from sympy.simplify.radsimp import fraction +from sympy.simplify.simplify import simplify +from sympy.solvers.solvers import solve +from sympy.strategies.core import switch, do_one, null_safe, condition +from sympy.utilities.iterables import iterable +from sympy.utilities.misc import debug + + +@dataclass +class Rule(ABC): + integrand: Expr + variable: Symbol + + @abstractmethod + def eval(self) -> Expr: + pass + + @abstractmethod + def contains_dont_know(self) -> bool: + pass + + +@dataclass +class AtomicRule(Rule, ABC): + """A simple rule that does not depend on other rules""" + def contains_dont_know(self) -> bool: + return False + + +@dataclass +class ConstantRule(AtomicRule): + """integrate(a, x) -> a*x""" + def eval(self) -> Expr: + return self.integrand * self.variable + + +@dataclass +class ConstantTimesRule(Rule): + """integrate(a*f(x), x) -> a*integrate(f(x), x)""" + constant: Expr + other: Expr + substep: Rule + + def eval(self) -> Expr: + return self.constant * self.substep.eval() + + def contains_dont_know(self) -> bool: + return self.substep.contains_dont_know() + + +@dataclass +class PowerRule(AtomicRule): + """integrate(x**a, x)""" + base: Expr + exp: Expr + + def eval(self) -> Expr: + return Piecewise( + ((self.base**(self.exp + 1))/(self.exp + 1), Ne(self.exp, -1)), + (log(self.base), True), + ) + + +@dataclass +class NestedPowRule(AtomicRule): + """integrate((x**a)**b, x)""" + base: Expr + exp: Expr + + def eval(self) -> Expr: + m = self.base * self.integrand + return Piecewise((m / (self.exp + 1), Ne(self.exp, -1)), + (m * log(self.base), True)) + + +@dataclass +class AddRule(Rule): + """integrate(f(x) + g(x), x) -> integrate(f(x), x) + integrate(g(x), x)""" + substeps: list[Rule] + + def eval(self) -> Expr: + return Add(*(substep.eval() for substep in self.substeps)) + + def contains_dont_know(self) -> bool: + return any(substep.contains_dont_know() for substep in self.substeps) + + +@dataclass +class URule(Rule): + """integrate(f(g(x))*g'(x), x) -> integrate(f(u), u), u = g(x)""" + u_var: Symbol + u_func: Expr + substep: Rule + + def eval(self) -> Expr: + result = self.substep.eval() + if self.u_func.is_Pow: + base, exp_ = self.u_func.as_base_exp() + if exp_ == -1: + # avoid needless -log(1/x) from substitution + result = result.subs(log(self.u_var), -log(base)) + return result.subs(self.u_var, self.u_func) + + def contains_dont_know(self) -> bool: + return self.substep.contains_dont_know() + + +@dataclass +class PartsRule(Rule): + """integrate(u(x)*v'(x), x) -> u(x)*v(x) - integrate(u'(x)*v(x), x)""" + u: Symbol + dv: Expr + v_step: Rule + second_step: Rule | None # None when is a substep of CyclicPartsRule + + def eval(self) -> Expr: + assert self.second_step is not None + v = self.v_step.eval() + return self.u * v - self.second_step.eval() + + def contains_dont_know(self) -> bool: + return self.v_step.contains_dont_know() or ( + self.second_step is not None and self.second_step.contains_dont_know()) + + +@dataclass +class CyclicPartsRule(Rule): + """Apply PartsRule multiple times to integrate exp(x)*sin(x)""" + parts_rules: list[PartsRule] + coefficient: Expr + + def eval(self) -> Expr: + result = [] + sign = 1 + for rule in self.parts_rules: + result.append(sign * rule.u * rule.v_step.eval()) + sign *= -1 + return Add(*result) / (1 - self.coefficient) + + def contains_dont_know(self) -> bool: + return any(substep.contains_dont_know() for substep in self.parts_rules) + + +@dataclass +class TrigRule(AtomicRule, ABC): + pass + + +@dataclass +class SinRule(TrigRule): + """integrate(sin(x), x) -> -cos(x)""" + def eval(self) -> Expr: + return -cos(self.variable) + + +@dataclass +class CosRule(TrigRule): + """integrate(cos(x), x) -> sin(x)""" + def eval(self) -> Expr: + return sin(self.variable) + + +@dataclass +class SecTanRule(TrigRule): + """integrate(sec(x)*tan(x), x) -> sec(x)""" + def eval(self) -> Expr: + return sec(self.variable) + + +@dataclass +class CscCotRule(TrigRule): + """integrate(csc(x)*cot(x), x) -> -csc(x)""" + def eval(self) -> Expr: + return -csc(self.variable) + + +@dataclass +class Sec2Rule(TrigRule): + """integrate(sec(x)**2, x) -> tan(x)""" + def eval(self) -> Expr: + return tan(self.variable) + + +@dataclass +class Csc2Rule(TrigRule): + """integrate(csc(x)**2, x) -> -cot(x)""" + def eval(self) -> Expr: + return -cot(self.variable) + + +@dataclass +class HyperbolicRule(AtomicRule, ABC): + pass + + +@dataclass +class SinhRule(HyperbolicRule): + """integrate(sinh(x), x) -> cosh(x)""" + def eval(self) -> Expr: + return cosh(self.variable) + + +@dataclass +class CoshRule(HyperbolicRule): + """integrate(cosh(x), x) -> sinh(x)""" + def eval(self): + return sinh(self.variable) + + +@dataclass +class ExpRule(AtomicRule): + """integrate(a**x, x) -> a**x/ln(a)""" + base: Expr + exp: Expr + + def eval(self) -> Expr: + return self.integrand / log(self.base) + + +@dataclass +class ReciprocalRule(AtomicRule): + """integrate(1/x, x) -> ln(x)""" + base: Expr + + def eval(self) -> Expr: + return log(self.base) + + +@dataclass +class ArcsinRule(AtomicRule): + """integrate(1/sqrt(1-x**2), x) -> asin(x)""" + def eval(self) -> Expr: + return asin(self.variable) + + +@dataclass +class ArcsinhRule(AtomicRule): + """integrate(1/sqrt(1+x**2), x) -> asin(x)""" + def eval(self) -> Expr: + return asinh(self.variable) + + +@dataclass +class ReciprocalSqrtQuadraticRule(AtomicRule): + """integrate(1/sqrt(a+b*x+c*x**2), x) -> log(2*sqrt(c)*sqrt(a+b*x+c*x**2)+b+2*c*x)/sqrt(c)""" + a: Expr + b: Expr + c: Expr + + def eval(self) -> Expr: + a, b, c, x = self.a, self.b, self.c, self.variable + return log(2*sqrt(c)*sqrt(a+b*x+c*x**2)+b+2*c*x)/sqrt(c) + + +@dataclass +class SqrtQuadraticDenomRule(AtomicRule): + """integrate(poly(x)/sqrt(a+b*x+c*x**2), x)""" + a: Expr + b: Expr + c: Expr + coeffs: list[Expr] + + def eval(self) -> Expr: + a, b, c, coeffs, x = self.a, self.b, self.c, self.coeffs.copy(), self.variable + # Integrate poly/sqrt(a+b*x+c*x**2) using recursion. + # coeffs are coefficients of the polynomial. + # Let I_n = x**n/sqrt(a+b*x+c*x**2), then + # I_n = A * x**(n-1)*sqrt(a+b*x+c*x**2) - B * I_{n-1} - C * I_{n-2} + # where A = 1/(n*c), B = (2*n-1)*b/(2*n*c), C = (n-1)*a/(n*c) + # See https://github.com/sympy/sympy/pull/23608 for proof. + result_coeffs = [] + coeffs = coeffs.copy() + for i in range(len(coeffs)-2): + n = len(coeffs)-1-i + coeff = coeffs[i]/(c*n) + result_coeffs.append(coeff) + coeffs[i+1] -= (2*n-1)*b/2*coeff + coeffs[i+2] -= (n-1)*a*coeff + d, e = coeffs[-1], coeffs[-2] + s = sqrt(a+b*x+c*x**2) + constant = d-b*e/(2*c) + if constant == 0: + I0 = 0 + else: + step = inverse_trig_rule(IntegralInfo(1/s, x), degenerate=False) + I0 = constant*step.eval() + return Add(*(result_coeffs[i]*x**(len(coeffs)-2-i) + for i in range(len(result_coeffs))), e/c)*s + I0 + + +@dataclass +class SqrtQuadraticRule(AtomicRule): + """integrate(sqrt(a+b*x+c*x**2), x)""" + a: Expr + b: Expr + c: Expr + + def eval(self) -> Expr: + step = sqrt_quadratic_rule(IntegralInfo(self.integrand, self.variable), degenerate=False) + return step.eval() + + +@dataclass +class AlternativeRule(Rule): + """Multiple ways to do integration.""" + alternatives: list[Rule] + + def eval(self) -> Expr: + return self.alternatives[0].eval() + + def contains_dont_know(self) -> bool: + return any(substep.contains_dont_know() for substep in self.alternatives) + + +@dataclass +class DontKnowRule(Rule): + """Leave the integral as is.""" + def eval(self) -> Expr: + return Integral(self.integrand, self.variable) + + def contains_dont_know(self) -> bool: + return True + + +@dataclass +class DerivativeRule(AtomicRule): + """integrate(f'(x), x) -> f(x)""" + def eval(self) -> Expr: + assert isinstance(self.integrand, Derivative) + variable_count = list(self.integrand.variable_count) + for i, (var, count) in enumerate(variable_count): + if var == self.variable: + variable_count[i] = (var, count - 1) + break + return Derivative(self.integrand.expr, *variable_count) + + +@dataclass +class RewriteRule(Rule): + """Rewrite integrand to another form that is easier to handle.""" + rewritten: Expr + substep: Rule + + def eval(self) -> Expr: + return self.substep.eval() + + def contains_dont_know(self) -> bool: + return self.substep.contains_dont_know() + + +@dataclass +class CompleteSquareRule(RewriteRule): + """Rewrite a+b*x+c*x**2 to a-b**2/(4*c) + c*(x+b/(2*c))**2""" + pass + + +@dataclass +class PiecewiseRule(Rule): + subfunctions: Sequence[tuple[Rule, bool | Boolean]] + + def eval(self) -> Expr: + return Piecewise(*[(substep.eval(), cond) + for substep, cond in self.subfunctions]) + + def contains_dont_know(self) -> bool: + return any(substep.contains_dont_know() for substep, _ in self.subfunctions) + + +@dataclass +class HeavisideRule(Rule): + harg: Expr + ibnd: Expr + substep: Rule + + def eval(self) -> Expr: + # If we are integrating over x and the integrand has the form + # Heaviside(m*x+b)*g(x) == Heaviside(harg)*g(symbol) + # then there needs to be continuity at -b/m == ibnd, + # so we subtract the appropriate term. + result = self.substep.eval() + return Heaviside(self.harg) * (result - result.subs(self.variable, self.ibnd)) + + def contains_dont_know(self) -> bool: + return self.substep.contains_dont_know() + + +@dataclass +class DiracDeltaRule(AtomicRule): + n: Expr + a: Expr + b: Expr + + def eval(self) -> Expr: + n, a, b, x = self.n, self.a, self.b, self.variable + if n == 0: + return Heaviside(a+b*x)/b + return DiracDelta(a+b*x, n-1)/b + + +@dataclass +class TrigSubstitutionRule(Rule): + theta: Expr + func: Expr + rewritten: Expr + substep: Rule + restriction: bool | Boolean + + def eval(self) -> Expr: + theta, func, x = self.theta, self.func, self.variable + func = func.subs(sec(theta), 1/cos(theta)) + func = func.subs(csc(theta), 1/sin(theta)) + func = func.subs(cot(theta), 1/tan(theta)) + + trig_function = list(func.find(TrigonometricFunction)) + assert len(trig_function) == 1 + trig_function = trig_function[0] + relation = solve(x - func, trig_function) + assert len(relation) == 1 + numer, denom = fraction(relation[0]) + + if isinstance(trig_function, sin): + opposite = numer + hypotenuse = denom + adjacent = sqrt(denom**2 - numer**2) + inverse = asin(relation[0]) + elif isinstance(trig_function, cos): + adjacent = numer + hypotenuse = denom + opposite = sqrt(denom**2 - numer**2) + inverse = acos(relation[0]) + else: # tan + opposite = numer + adjacent = denom + hypotenuse = sqrt(denom**2 + numer**2) + inverse = atan(relation[0]) + + substitution = [ + (sin(theta), opposite/hypotenuse), + (cos(theta), adjacent/hypotenuse), + (tan(theta), opposite/adjacent), + (theta, inverse) + ] + return Piecewise( + (self.substep.eval().subs(substitution).trigsimp(), self.restriction) # type: ignore + ) + + def contains_dont_know(self) -> bool: + return self.substep.contains_dont_know() + + +@dataclass +class ArctanRule(AtomicRule): + """integrate(a/(b*x**2+c), x) -> a/b / sqrt(c/b) * atan(x/sqrt(c/b))""" + a: Expr + b: Expr + c: Expr + + def eval(self) -> Expr: + a, b, c, x = self.a, self.b, self.c, self.variable + return a/b / sqrt(c/b) * atan(x/sqrt(c/b)) + + +@dataclass +class OrthogonalPolyRule(AtomicRule, ABC): + n: Expr + + +@dataclass +class JacobiRule(OrthogonalPolyRule): + a: Expr + b: Expr + + def eval(self) -> Expr: + n, a, b, x = self.n, self.a, self.b, self.variable + return Piecewise( + (2*jacobi(n + 1, a - 1, b - 1, x)/(n + a + b), Ne(n + a + b, 0)), + (x, Eq(n, 0)), + ((a + b + 2)*x**2/4 + (a - b)*x/2, Eq(n, 1))) + + +@dataclass +class GegenbauerRule(OrthogonalPolyRule): + a: Expr + + def eval(self) -> Expr: + n, a, x = self.n, self.a, self.variable + return Piecewise( + (gegenbauer(n + 1, a - 1, x)/(2*(a - 1)), Ne(a, 1)), + (chebyshevt(n + 1, x)/(n + 1), Ne(n, -1)), + (S.Zero, True)) + + +@dataclass +class ChebyshevTRule(OrthogonalPolyRule): + def eval(self) -> Expr: + n, x = self.n, self.variable + return Piecewise( + ((chebyshevt(n + 1, x)/(n + 1) - + chebyshevt(n - 1, x)/(n - 1))/2, Ne(Abs(n), 1)), + (x**2/2, True)) + + +@dataclass +class ChebyshevURule(OrthogonalPolyRule): + def eval(self) -> Expr: + n, x = self.n, self.variable + return Piecewise( + (chebyshevt(n + 1, x)/(n + 1), Ne(n, -1)), + (S.Zero, True)) + + +@dataclass +class LegendreRule(OrthogonalPolyRule): + def eval(self) -> Expr: + n, x = self.n, self.variable + return(legendre(n + 1, x) - legendre(n - 1, x))/(2*n + 1) + + +@dataclass +class HermiteRule(OrthogonalPolyRule): + def eval(self) -> Expr: + n, x = self.n, self.variable + return hermite(n + 1, x)/(2*(n + 1)) + + +@dataclass +class LaguerreRule(OrthogonalPolyRule): + def eval(self) -> Expr: + n, x = self.n, self.variable + return laguerre(n, x) - laguerre(n + 1, x) + + +@dataclass +class AssocLaguerreRule(OrthogonalPolyRule): + a: Expr + + def eval(self) -> Expr: + return -assoc_laguerre(self.n + 1, self.a - 1, self.variable) + + +@dataclass +class IRule(AtomicRule, ABC): + a: Expr + b: Expr + + +@dataclass +class CiRule(IRule): + def eval(self) -> Expr: + a, b, x = self.a, self.b, self.variable + return cos(b)*Ci(a*x) - sin(b)*Si(a*x) + + +@dataclass +class ChiRule(IRule): + def eval(self) -> Expr: + a, b, x = self.a, self.b, self.variable + return cosh(b)*Chi(a*x) + sinh(b)*Shi(a*x) + + +@dataclass +class EiRule(IRule): + def eval(self) -> Expr: + a, b, x = self.a, self.b, self.variable + return exp(b)*Ei(a*x) + + +@dataclass +class SiRule(IRule): + def eval(self) -> Expr: + a, b, x = self.a, self.b, self.variable + return sin(b)*Ci(a*x) + cos(b)*Si(a*x) + + +@dataclass +class ShiRule(IRule): + def eval(self) -> Expr: + a, b, x = self.a, self.b, self.variable + return sinh(b)*Chi(a*x) + cosh(b)*Shi(a*x) + + +@dataclass +class LiRule(IRule): + def eval(self) -> Expr: + a, b, x = self.a, self.b, self.variable + return li(a*x + b)/a + + +@dataclass +class ErfRule(AtomicRule): + a: Expr + b: Expr + c: Expr + + def eval(self) -> Expr: + a, b, c, x = self.a, self.b, self.c, self.variable + if a.is_extended_real: + return Piecewise( + (sqrt(S.Pi)/sqrt(-a)/2 * exp(c - b**2/(4*a)) * + erf((-2*a*x - b)/(2*sqrt(-a))), a < 0), + (sqrt(S.Pi)/sqrt(a)/2 * exp(c - b**2/(4*a)) * + erfi((2*a*x + b)/(2*sqrt(a))), True)) + return sqrt(S.Pi)/sqrt(a)/2 * exp(c - b**2/(4*a)) * \ + erfi((2*a*x + b)/(2*sqrt(a))) + + +@dataclass +class FresnelCRule(AtomicRule): + a: Expr + b: Expr + c: Expr + + def eval(self) -> Expr: + a, b, c, x = self.a, self.b, self.c, self.variable + return sqrt(S.Pi)/sqrt(2*a) * ( + cos(b**2/(4*a) - c)*fresnelc((2*a*x + b)/sqrt(2*a*S.Pi)) + + sin(b**2/(4*a) - c)*fresnels((2*a*x + b)/sqrt(2*a*S.Pi))) + + +@dataclass +class FresnelSRule(AtomicRule): + a: Expr + b: Expr + c: Expr + + def eval(self) -> Expr: + a, b, c, x = self.a, self.b, self.c, self.variable + return sqrt(S.Pi)/sqrt(2*a) * ( + cos(b**2/(4*a) - c)*fresnels((2*a*x + b)/sqrt(2*a*S.Pi)) - + sin(b**2/(4*a) - c)*fresnelc((2*a*x + b)/sqrt(2*a*S.Pi))) + + +@dataclass +class PolylogRule(AtomicRule): + a: Expr + b: Expr + + def eval(self) -> Expr: + return polylog(self.b + 1, self.a * self.variable) + + +@dataclass +class UpperGammaRule(AtomicRule): + a: Expr + e: Expr + + def eval(self) -> Expr: + a, e, x = self.a, self.e, self.variable + return x**e * (-a*x)**(-e) * uppergamma(e + 1, -a*x)/a + + +@dataclass +class EllipticFRule(AtomicRule): + a: Expr + d: Expr + + def eval(self) -> Expr: + return elliptic_f(self.variable, self.d/self.a)/sqrt(self.a) + + +@dataclass +class EllipticERule(AtomicRule): + a: Expr + d: Expr + + def eval(self) -> Expr: + return elliptic_e(self.variable, self.d/self.a)*sqrt(self.a) + + +class IntegralInfo(NamedTuple): + integrand: Expr + symbol: Symbol + + +def manual_diff(f, symbol): + """Derivative of f in form expected by find_substitutions + + SymPy's derivatives for some trig functions (like cot) are not in a form + that works well with finding substitutions; this replaces the + derivatives for those particular forms with something that works better. + + """ + if f.args: + arg = f.args[0] + if isinstance(f, tan): + return arg.diff(symbol) * sec(arg)**2 + elif isinstance(f, cot): + return -arg.diff(symbol) * csc(arg)**2 + elif isinstance(f, sec): + return arg.diff(symbol) * sec(arg) * tan(arg) + elif isinstance(f, csc): + return -arg.diff(symbol) * csc(arg) * cot(arg) + elif isinstance(f, Add): + return sum(manual_diff(arg, symbol) for arg in f.args) + elif isinstance(f, Mul): + if len(f.args) == 2 and isinstance(f.args[0], Number): + return f.args[0] * manual_diff(f.args[1], symbol) + return f.diff(symbol) + +def manual_subs(expr, *args): + """ + A wrapper for `expr.subs(*args)` with additional logic for substitution + of invertible functions. + """ + if len(args) == 1: + sequence = args[0] + if isinstance(sequence, (Dict, Mapping)): + sequence = sequence.items() + elif not iterable(sequence): + raise ValueError("Expected an iterable of (old, new) pairs") + elif len(args) == 2: + sequence = [args] + else: + raise ValueError("subs accepts either 1 or 2 arguments") + + new_subs = [] + for old, new in sequence: + if isinstance(old, log): + # If log(x) = y, then exp(a*log(x)) = exp(a*y) + # that is, x**a = exp(a*y). Replace nontrivial powers of x + # before subs turns them into `exp(y)**a`, but + # do not replace x itself yet, to avoid `log(exp(y))`. + x0 = old.args[0] + expr = expr.replace(lambda x: x.is_Pow and x.base == x0, + lambda x: exp(x.exp*new)) + new_subs.append((x0, exp(new))) + + return expr.subs(list(sequence) + new_subs) + +# Method based on that on SIN, described in "Symbolic Integration: The +# Stormy Decade" + +inverse_trig_functions = (atan, asin, acos, acot, acsc, asec) + + +def find_substitutions(integrand, symbol, u_var): + results = [] + + def test_subterm(u, u_diff): + if u_diff == 0: + return False + substituted = integrand / u_diff + debug("substituted: {}, u: {}, u_var: {}".format(substituted, u, u_var)) + substituted = manual_subs(substituted, u, u_var).cancel() + + if substituted.has_free(symbol): + return False + # avoid increasing the degree of a rational function + if integrand.is_rational_function(symbol) and substituted.is_rational_function(u_var): + deg_before = max(degree(t, symbol) for t in integrand.as_numer_denom()) + deg_after = max(degree(t, u_var) for t in substituted.as_numer_denom()) + if deg_after > deg_before: + return False + return substituted.as_independent(u_var, as_Add=False) + + def exp_subterms(term: Expr): + linear_coeffs = [] + terms = [] + n = Wild('n', properties=[lambda n: n.is_Integer]) + for exp_ in term.find(exp): + arg = exp_.args[0] + if symbol not in arg.free_symbols: + continue + match = arg.match(n*symbol) + if match: + linear_coeffs.append(match[n]) + else: + terms.append(exp_) + if linear_coeffs: + terms.append(exp(gcd_list(linear_coeffs)*symbol)) + return terms + + def possible_subterms(term): + if isinstance(term, (TrigonometricFunction, HyperbolicFunction, + *inverse_trig_functions, + exp, log, Heaviside)): + return [term.args[0]] + elif isinstance(term, (chebyshevt, chebyshevu, + legendre, hermite, laguerre)): + return [term.args[1]] + elif isinstance(term, (gegenbauer, assoc_laguerre)): + return [term.args[2]] + elif isinstance(term, jacobi): + return [term.args[3]] + elif isinstance(term, Mul): + r = [] + for u in term.args: + r.append(u) + r.extend(possible_subterms(u)) + return r + elif isinstance(term, Pow): + r = [arg for arg in term.args if arg.has(symbol)] + if term.exp.is_Integer: + r.extend([term.base**d for d in primefactors(term.exp) + if 1 < d < abs(term.args[1])]) + if term.base.is_Add: + r.extend([t for t in possible_subterms(term.base) + if t.is_Pow]) + return r + elif isinstance(term, Add): + r = [] + for arg in term.args: + r.append(arg) + r.extend(possible_subterms(arg)) + return r + return [] + + for u in list(dict.fromkeys(possible_subterms(integrand) + exp_subterms(integrand))): + if u == symbol: + continue + u_diff = manual_diff(u, symbol) + new_integrand = test_subterm(u, u_diff) + if new_integrand is not False: + constant, new_integrand = new_integrand + if new_integrand == integrand.subs(symbol, u_var): + continue + substitution = (u, constant, new_integrand) + if substitution not in results: + results.append(substitution) + + return results + +def rewriter(condition, rewrite): + """Strategy that rewrites an integrand.""" + def _rewriter(integral): + integrand, symbol = integral + debug("Integral: {} is rewritten with {} on symbol: {}".format(integrand, rewrite, symbol)) + if condition(*integral): + rewritten = rewrite(*integral) + if rewritten != integrand: + substep = integral_steps(rewritten, symbol) + if not isinstance(substep, DontKnowRule) and substep: + return RewriteRule(integrand, symbol, rewritten, substep) + return _rewriter + +def proxy_rewriter(condition, rewrite): + """Strategy that rewrites an integrand based on some other criteria.""" + def _proxy_rewriter(criteria): + criteria, integral = criteria + integrand, symbol = integral + debug("Integral: {} is rewritten with {} on symbol: {} and criteria: {}".format(integrand, rewrite, symbol, criteria)) + args = criteria + list(integral) + if condition(*args): + rewritten = rewrite(*args) + if rewritten != integrand: + return RewriteRule(integrand, symbol, rewritten, integral_steps(rewritten, symbol)) + return _proxy_rewriter + +def multiplexer(conditions): + """Apply the rule that matches the condition, else None""" + def multiplexer_rl(expr): + for key, rule in conditions.items(): + if key(expr): + return rule(expr) + return multiplexer_rl + +def alternatives(*rules): + """Strategy that makes an AlternativeRule out of multiple possible results.""" + def _alternatives(integral): + alts = [] + count = 0 + debug("List of Alternative Rules") + for rule in rules: + count = count + 1 + debug("Rule {}: {}".format(count, rule)) + + result = rule(integral) + if (result and not isinstance(result, DontKnowRule) and + result != integral and result not in alts): + alts.append(result) + if len(alts) == 1: + return alts[0] + elif alts: + doable = [rule for rule in alts if not rule.contains_dont_know()] + if doable: + return AlternativeRule(*integral, doable) + else: + return AlternativeRule(*integral, alts) + return _alternatives + +def constant_rule(integral): + return ConstantRule(*integral) + +def power_rule(integral): + integrand, symbol = integral + base, expt = integrand.as_base_exp() + + if symbol not in expt.free_symbols and isinstance(base, Symbol): + if simplify(expt + 1) == 0: + return ReciprocalRule(integrand, symbol, base) + return PowerRule(integrand, symbol, base, expt) + elif symbol not in base.free_symbols and isinstance(expt, Symbol): + rule = ExpRule(integrand, symbol, base, expt) + + if fuzzy_not(log(base).is_zero): + return rule + elif log(base).is_zero: + return ConstantRule(1, symbol) + + return PiecewiseRule(integrand, symbol, [ + (rule, Ne(log(base), 0)), + (ConstantRule(1, symbol), True) + ]) + +def exp_rule(integral): + integrand, symbol = integral + if isinstance(integrand.args[0], Symbol): + return ExpRule(integrand, symbol, E, integrand.args[0]) + + +def orthogonal_poly_rule(integral): + orthogonal_poly_classes = { + jacobi: JacobiRule, + gegenbauer: GegenbauerRule, + chebyshevt: ChebyshevTRule, + chebyshevu: ChebyshevURule, + legendre: LegendreRule, + hermite: HermiteRule, + laguerre: LaguerreRule, + assoc_laguerre: AssocLaguerreRule + } + orthogonal_poly_var_index = { + jacobi: 3, + gegenbauer: 2, + assoc_laguerre: 2 + } + integrand, symbol = integral + for klass in orthogonal_poly_classes: + if isinstance(integrand, klass): + var_index = orthogonal_poly_var_index.get(klass, 1) + if (integrand.args[var_index] is symbol and not + any(v.has(symbol) for v in integrand.args[:var_index])): + return orthogonal_poly_classes[klass](integrand, symbol, *integrand.args[:var_index]) + + +_special_function_patterns: list[tuple[Type, Expr, Callable | None, tuple]] = [] +_wilds = [] +_symbol = Dummy('x') + + +def special_function_rule(integral): + integrand, symbol = integral + if not _special_function_patterns: + a = Wild('a', exclude=[_symbol], properties=[lambda x: not x.is_zero]) + b = Wild('b', exclude=[_symbol]) + c = Wild('c', exclude=[_symbol]) + d = Wild('d', exclude=[_symbol], properties=[lambda x: not x.is_zero]) + e = Wild('e', exclude=[_symbol], properties=[ + lambda x: not (x.is_nonnegative and x.is_integer)]) + _wilds.extend((a, b, c, d, e)) + # patterns consist of a SymPy class, a wildcard expr, an optional + # condition coded as a lambda (when Wild properties are not enough), + # followed by an applicable rule + linear_pattern = a*_symbol + b + quadratic_pattern = a*_symbol**2 + b*_symbol + c + _special_function_patterns.extend(( + (Mul, exp(linear_pattern, evaluate=False)/_symbol, None, EiRule), + (Mul, cos(linear_pattern, evaluate=False)/_symbol, None, CiRule), + (Mul, cosh(linear_pattern, evaluate=False)/_symbol, None, ChiRule), + (Mul, sin(linear_pattern, evaluate=False)/_symbol, None, SiRule), + (Mul, sinh(linear_pattern, evaluate=False)/_symbol, None, ShiRule), + (Pow, 1/log(linear_pattern, evaluate=False), None, LiRule), + (exp, exp(quadratic_pattern, evaluate=False), None, ErfRule), + (sin, sin(quadratic_pattern, evaluate=False), None, FresnelSRule), + (cos, cos(quadratic_pattern, evaluate=False), None, FresnelCRule), + (Mul, _symbol**e*exp(a*_symbol, evaluate=False), None, UpperGammaRule), + (Mul, polylog(b, a*_symbol, evaluate=False)/_symbol, None, PolylogRule), + (Pow, 1/sqrt(a - d*sin(_symbol, evaluate=False)**2), + lambda a, d: a != d, EllipticFRule), + (Pow, sqrt(a - d*sin(_symbol, evaluate=False)**2), + lambda a, d: a != d, EllipticERule), + )) + _integrand = integrand.subs(symbol, _symbol) + for type_, pattern, constraint, rule in _special_function_patterns: + if isinstance(_integrand, type_): + match = _integrand.match(pattern) + if match: + wild_vals = tuple(match.get(w) for w in _wilds + if match.get(w) is not None) + if constraint is None or constraint(*wild_vals): + return rule(integrand, symbol, *wild_vals) + + +def _add_degenerate_step(generic_cond, generic_step: Rule, degenerate_step: Rule | None) -> Rule: + if degenerate_step is None: + return generic_step + if isinstance(generic_step, PiecewiseRule): + subfunctions = [(substep, (cond & generic_cond).simplify()) + for substep, cond in generic_step.subfunctions] + else: + subfunctions = [(generic_step, generic_cond)] + if isinstance(degenerate_step, PiecewiseRule): + subfunctions += degenerate_step.subfunctions + else: + subfunctions.append((degenerate_step, S.true)) + return PiecewiseRule(generic_step.integrand, generic_step.variable, subfunctions) + + +def nested_pow_rule(integral: IntegralInfo): + # nested (c*(a+b*x)**d)**e + integrand, x = integral + + a_ = Wild('a', exclude=[x]) + b_ = Wild('b', exclude=[x, 0]) + pattern = a_+b_*x + generic_cond = S.true + + class NoMatch(Exception): + pass + + def _get_base_exp(expr: Expr) -> tuple[Expr, Expr]: + if not expr.has_free(x): + return S.One, S.Zero + if expr.is_Mul: + _, terms = expr.as_coeff_mul() + if not terms: + return S.One, S.Zero + results = [_get_base_exp(term) for term in terms] + bases = {b for b, _ in results} + bases.discard(S.One) + if len(bases) == 1: + return bases.pop(), Add(*(e for _, e in results)) + raise NoMatch + if expr.is_Pow: + b, e = expr.base, expr.exp # type: ignore + if e.has_free(x): + raise NoMatch + base_, sub_exp = _get_base_exp(b) + return base_, sub_exp * e + match = expr.match(pattern) + if match: + a, b = match[a_], match[b_] + base_ = x + a/b + nonlocal generic_cond + generic_cond = Ne(b, 0) + return base_, S.One + raise NoMatch + + try: + base, exp_ = _get_base_exp(integrand) + except NoMatch: + return + if generic_cond is S.true: + degenerate_step = None + else: + # equivalent with subs(b, 0) but no need to find b + degenerate_step = ConstantRule(integrand.subs(x, 0), x) + generic_step = NestedPowRule(integrand, x, base, exp_) + return _add_degenerate_step(generic_cond, generic_step, degenerate_step) + + +def inverse_trig_rule(integral: IntegralInfo, degenerate=True): + """ + Set degenerate=False on recursive call where coefficient of quadratic term + is assumed non-zero. + """ + integrand, symbol = integral + base, exp = integrand.as_base_exp() + a = Wild('a', exclude=[symbol]) + b = Wild('b', exclude=[symbol]) + c = Wild('c', exclude=[symbol, 0]) + match = base.match(a + b*symbol + c*symbol**2) + + if not match: + return + + def make_inverse_trig(RuleClass, a, sign_a, c, sign_c, h) -> Rule: + u_var = Dummy("u") + rewritten = 1/sqrt(sign_a*a + sign_c*c*(symbol-h)**2) # a>0, c>0 + quadratic_base = sqrt(c/a)*(symbol-h) + constant = 1/sqrt(c) + u_func = None + if quadratic_base is not symbol: + u_func = quadratic_base + quadratic_base = u_var + standard_form = 1/sqrt(sign_a + sign_c*quadratic_base**2) + substep = RuleClass(standard_form, quadratic_base) + if constant != 1: + substep = ConstantTimesRule(constant*standard_form, symbol, constant, standard_form, substep) + if u_func is not None: + substep = URule(rewritten, symbol, u_var, u_func, substep) + if h != 0: + substep = CompleteSquareRule(integrand, symbol, rewritten, substep) + return substep + + a, b, c = [match.get(i, S.Zero) for i in (a, b, c)] + generic_cond = Ne(c, 0) + if not degenerate or generic_cond is S.true: + degenerate_step = None + elif b.is_zero: + degenerate_step = ConstantRule(a ** exp, symbol) + else: + degenerate_step = sqrt_linear_rule(IntegralInfo((a + b * symbol) ** exp, symbol)) + + if simplify(2*exp + 1) == 0: + h, k = -b/(2*c), a - b**2/(4*c) # rewrite base to k + c*(symbol-h)**2 + non_square_cond = Ne(k, 0) + square_step = None + if non_square_cond is not S.true: + square_step = NestedPowRule(1/sqrt(c*(symbol-h)**2), symbol, symbol-h, S.NegativeOne) + if non_square_cond is S.false: + return square_step + generic_step = ReciprocalSqrtQuadraticRule(integrand, symbol, a, b, c) + step = _add_degenerate_step(non_square_cond, generic_step, square_step) + if k.is_real and c.is_real: + # list of ((rule, base_exp, a, sign_a, b, sign_b), condition) + rules = [] + for args, cond in ( # don't apply ArccoshRule to x**2-1 + ((ArcsinRule, k, 1, -c, -1, h), And(k > 0, c < 0)), # 1-x**2 + ((ArcsinhRule, k, 1, c, 1, h), And(k > 0, c > 0)), # 1+x**2 + ): + if cond is S.true: + return make_inverse_trig(*args) + if cond is not S.false: + rules.append((make_inverse_trig(*args), cond)) + if rules: + if not k.is_positive: # conditions are not thorough, need fall back rule + rules.append((generic_step, S.true)) + step = PiecewiseRule(integrand, symbol, rules) + else: + step = generic_step + return _add_degenerate_step(generic_cond, step, degenerate_step) + if exp == S.Half: + step = SqrtQuadraticRule(integrand, symbol, a, b, c) + return _add_degenerate_step(generic_cond, step, degenerate_step) + + +def add_rule(integral): + integrand, symbol = integral + results = [integral_steps(g, symbol) + for g in integrand.as_ordered_terms()] + return None if None in results else AddRule(integrand, symbol, results) + + +def mul_rule(integral: IntegralInfo): + integrand, symbol = integral + + # Constant times function case + coeff, f = integrand.as_independent(symbol) + if coeff != 1: + next_step = integral_steps(f, symbol) + if next_step is not None: + return ConstantTimesRule(integrand, symbol, coeff, f, next_step) + + +def _parts_rule(integrand, symbol) -> tuple[Expr, Expr, Expr, Expr, Rule] | None: + # LIATE rule: + # log, inverse trig, algebraic, trigonometric, exponential + def pull_out_algebraic(integrand): + integrand = integrand.cancel().together() + # iterating over Piecewise args would not work here + algebraic = ([] if isinstance(integrand, Piecewise) or not integrand.is_Mul + else [arg for arg in integrand.args if arg.is_algebraic_expr(symbol)]) + if algebraic: + u = Mul(*algebraic) + dv = (integrand / u).cancel() + return u, dv + + def pull_out_u(*functions) -> Callable[[Expr], tuple[Expr, Expr] | None]: + def pull_out_u_rl(integrand: Expr) -> tuple[Expr, Expr] | None: + if any(integrand.has(f) for f in functions): + args = [arg for arg in integrand.args + if any(isinstance(arg, cls) for cls in functions)] + if args: + u = Mul(*args) # type: ignore + dv = integrand / u + return u, dv + return None + + return pull_out_u_rl + + liate_rules = [pull_out_u(log), pull_out_u(*inverse_trig_functions), + pull_out_algebraic, pull_out_u(sin, cos), + pull_out_u(exp)] + + + dummy = Dummy("temporary") + # we can integrate log(x) and atan(x) by setting dv = 1 + if isinstance(integrand, (log, *inverse_trig_functions)): + integrand = dummy * integrand + + for index, rule in enumerate(liate_rules): + result = rule(integrand) + + if result: + u, dv = result + + # Don't pick u to be a constant if possible + if symbol not in u.free_symbols and not u.has(dummy): + return None + + u = u.subs(dummy, 1) + dv = dv.subs(dummy, 1) + + # Don't pick a non-polynomial algebraic to be differentiated + if rule == pull_out_algebraic and not u.is_polynomial(symbol): + return None + # Don't trade one logarithm for another + if isinstance(u, log): + rec_dv = 1/dv + if (rec_dv.is_polynomial(symbol) and + degree(rec_dv, symbol) == 1): + return None + + # Can integrate a polynomial times OrthogonalPolynomial + if rule == pull_out_algebraic: + if dv.is_Derivative or dv.has(TrigonometricFunction) or \ + isinstance(dv, OrthogonalPolynomial): + v_step = integral_steps(dv, symbol) + if v_step.contains_dont_know(): + return None + else: + du = u.diff(symbol) + v = v_step.eval() + return u, dv, v, du, v_step + + # make sure dv is amenable to integration + accept = False + if index < 2: # log and inverse trig are usually worth trying + accept = True + elif (rule == pull_out_algebraic and dv.args and + all(isinstance(a, (sin, cos, exp)) + for a in dv.args)): + accept = True + else: + for lrule in liate_rules[index + 1:]: + r = lrule(integrand) + if r and r[0].subs(dummy, 1).equals(dv): + accept = True + break + + if accept: + du = u.diff(symbol) + v_step = integral_steps(simplify(dv), symbol) + if not v_step.contains_dont_know(): + v = v_step.eval() + return u, dv, v, du, v_step + return None + + +def parts_rule(integral): + integrand, symbol = integral + constant, integrand = integrand.as_coeff_Mul() + + result = _parts_rule(integrand, symbol) + + steps = [] + if result: + u, dv, v, du, v_step = result + debug("u : {}, dv : {}, v : {}, du : {}, v_step: {}".format(u, dv, v, du, v_step)) + steps.append(result) + + if isinstance(v, Integral): + return + + # Set a limit on the number of times u can be used + if isinstance(u, (sin, cos, exp, sinh, cosh)): + cachekey = u.xreplace({symbol: _cache_dummy}) + if _parts_u_cache[cachekey] > 2: + return + _parts_u_cache[cachekey] += 1 + + # Try cyclic integration by parts a few times + for _ in range(4): + debug("Cyclic integration {} with v: {}, du: {}, integrand: {}".format(_, v, du, integrand)) + coefficient = ((v * du) / integrand).cancel() + if coefficient == 1: + break + if symbol not in coefficient.free_symbols: + rule = CyclicPartsRule(integrand, symbol, + [PartsRule(None, None, u, dv, v_step, None) + for (u, dv, v, du, v_step) in steps], + (-1) ** len(steps) * coefficient) + if (constant != 1) and rule: + rule = ConstantTimesRule(constant * integrand, symbol, constant, integrand, rule) + return rule + + # _parts_rule is sensitive to constants, factor it out + next_constant, next_integrand = (v * du).as_coeff_Mul() + result = _parts_rule(next_integrand, symbol) + + if result: + u, dv, v, du, v_step = result + u *= next_constant + du *= next_constant + steps.append((u, dv, v, du, v_step)) + else: + break + + def make_second_step(steps, integrand): + if steps: + u, dv, v, du, v_step = steps[0] + return PartsRule(integrand, symbol, u, dv, v_step, make_second_step(steps[1:], v * du)) + return integral_steps(integrand, symbol) + + if steps: + u, dv, v, du, v_step = steps[0] + rule = PartsRule(integrand, symbol, u, dv, v_step, make_second_step(steps[1:], v * du)) + if (constant != 1) and rule: + rule = ConstantTimesRule(constant * integrand, symbol, constant, integrand, rule) + return rule + + +def trig_rule(integral): + integrand, symbol = integral + if integrand == sin(symbol): + return SinRule(integrand, symbol) + if integrand == cos(symbol): + return CosRule(integrand, symbol) + if integrand == sec(symbol)**2: + return Sec2Rule(integrand, symbol) + if integrand == csc(symbol)**2: + return Csc2Rule(integrand, symbol) + + if isinstance(integrand, tan): + rewritten = sin(*integrand.args) / cos(*integrand.args) + elif isinstance(integrand, cot): + rewritten = cos(*integrand.args) / sin(*integrand.args) + elif isinstance(integrand, sec): + arg = integrand.args[0] + rewritten = ((sec(arg)**2 + tan(arg) * sec(arg)) / + (sec(arg) + tan(arg))) + elif isinstance(integrand, csc): + arg = integrand.args[0] + rewritten = ((csc(arg)**2 + cot(arg) * csc(arg)) / + (csc(arg) + cot(arg))) + else: + return + + return RewriteRule(integrand, symbol, rewritten, integral_steps(rewritten, symbol)) + +def trig_product_rule(integral: IntegralInfo): + integrand, symbol = integral + if integrand == sec(symbol) * tan(symbol): + return SecTanRule(integrand, symbol) + if integrand == csc(symbol) * cot(symbol): + return CscCotRule(integrand, symbol) + + +def quadratic_denom_rule(integral): + integrand, symbol = integral + a = Wild('a', exclude=[symbol]) + b = Wild('b', exclude=[symbol]) + c = Wild('c', exclude=[symbol]) + + match = integrand.match(a / (b * symbol ** 2 + c)) + + if match: + a, b, c = match[a], match[b], match[c] + general_rule = ArctanRule(integrand, symbol, a, b, c) + if b.is_extended_real and c.is_extended_real: + positive_cond = c/b > 0 + if positive_cond is S.true: + return general_rule + coeff = a/(2*sqrt(-c)*sqrt(b)) + constant = sqrt(-c/b) + r1 = 1/(symbol-constant) + r2 = 1/(symbol+constant) + log_steps = [ReciprocalRule(r1, symbol, symbol-constant), + ConstantTimesRule(-r2, symbol, -1, r2, ReciprocalRule(r2, symbol, symbol+constant))] + rewritten = sub = r1 - r2 + negative_step = AddRule(sub, symbol, log_steps) + if coeff != 1: + rewritten = Mul(coeff, sub, evaluate=False) + negative_step = ConstantTimesRule(rewritten, symbol, coeff, sub, negative_step) + negative_step = RewriteRule(integrand, symbol, rewritten, negative_step) + if positive_cond is S.false: + return negative_step + return PiecewiseRule(integrand, symbol, [(general_rule, positive_cond), (negative_step, S.true)]) + + power = PowerRule(integrand, symbol, symbol, -2) + if b != 1: + power = ConstantTimesRule(integrand, symbol, 1/b, symbol**-2, power) + + return PiecewiseRule(integrand, symbol, [(general_rule, Ne(c, 0)), (power, True)]) + + d = Wild('d', exclude=[symbol]) + match2 = integrand.match(a / (b * symbol ** 2 + c * symbol + d)) + if match2: + b, c = match2[b], match2[c] + if b.is_zero: + return + u = Dummy('u') + u_func = symbol + c/(2*b) + integrand2 = integrand.subs(symbol, u - c / (2*b)) + next_step = integral_steps(integrand2, u) + if next_step: + return URule(integrand2, symbol, u, u_func, next_step) + else: + return + e = Wild('e', exclude=[symbol]) + match3 = integrand.match((a* symbol + b) / (c * symbol ** 2 + d * symbol + e)) + if match3: + a, b, c, d, e = match3[a], match3[b], match3[c], match3[d], match3[e] + if c.is_zero: + return + denominator = c * symbol**2 + d * symbol + e + const = a/(2*c) + numer1 = (2*c*symbol+d) + numer2 = - const*d + b + u = Dummy('u') + step1 = URule(integrand, symbol, + u, denominator, integral_steps(u**(-1), u)) + if const != 1: + step1 = ConstantTimesRule(const*numer1/denominator, symbol, + const, numer1/denominator, step1) + if numer2.is_zero: + return step1 + step2 = integral_steps(numer2/denominator, symbol) + substeps = AddRule(integrand, symbol, [step1, step2]) + rewriten = const*numer1/denominator+numer2/denominator + return RewriteRule(integrand, symbol, rewriten, substeps) + + return + + +def sqrt_linear_rule(integral: IntegralInfo): + """ + Substitute common (a+b*x)**(1/n) + """ + integrand, x = integral + a = Wild('a', exclude=[x]) + b = Wild('b', exclude=[x, 0]) + a0 = b0 = 0 + bases, qs, bs = [], [], [] + for pow_ in integrand.find(Pow): # collect all (a+b*x)**(p/q) + base, exp_ = pow_.base, pow_.exp + if exp_.is_Integer or x not in base.free_symbols: # skip 1/x and sqrt(2) + continue + if not exp_.is_Rational: # exclude x**pi + return + match = base.match(a+b*x) + if not match: # skip non-linear + continue # for sqrt(x+sqrt(x)), although base is non-linear, we can still substitute sqrt(x) + a1, b1 = match[a], match[b] + if a0*b1 != a1*b0 or not (b0/b1).is_nonnegative: # cannot transform sqrt(x) to sqrt(x+1) or sqrt(-x) + return + if b0 == 0 or (b0/b1 > 1) is S.true: # choose the latter of sqrt(2*x) and sqrt(x) as representative + a0, b0 = a1, b1 + bases.append(base) + bs.append(b1) + qs.append(exp_.q) + if b0 == 0: # no such pattern found + return + q0: Integer = lcm_list(qs) + u_x = (a0 + b0*x)**(1/q0) + u = Dummy("u") + substituted = integrand.subs({base**(S.One/q): (b/b0)**(S.One/q)*u**(q0/q) + for base, b, q in zip(bases, bs, qs)}).subs(x, (u**q0-a0)/b0) + substep = integral_steps(substituted*u**(q0-1)*q0/b0, u) + if not substep.contains_dont_know(): + step: Rule = URule(integrand, x, u, u_x, substep) + generic_cond = Ne(b0, 0) + if generic_cond is not S.true: # possible degenerate case + simplified = integrand.subs(dict.fromkeys(bs, 0)) + degenerate_step = integral_steps(simplified, x) + step = PiecewiseRule(integrand, x, [(step, generic_cond), (degenerate_step, S.true)]) + return step + + +def sqrt_quadratic_rule(integral: IntegralInfo, degenerate=True): + integrand, x = integral + a = Wild('a', exclude=[x]) + b = Wild('b', exclude=[x]) + c = Wild('c', exclude=[x, 0]) + f = Wild('f') + n = Wild('n', properties=[lambda n: n.is_Integer and n.is_odd]) + match = integrand.match(f*sqrt(a+b*x+c*x**2)**n) + if not match: + return + a, b, c, f, n = match[a], match[b], match[c], match[f], match[n] + f_poly = f.as_poly(x) + if f_poly is None: + return + + generic_cond = Ne(c, 0) + if not degenerate or generic_cond is S.true: + degenerate_step = None + elif b.is_zero: + degenerate_step = integral_steps(f*sqrt(a)**n, x) + else: + degenerate_step = sqrt_linear_rule(IntegralInfo(f*sqrt(a+b*x)**n, x)) + + def sqrt_quadratic_denom_rule(numer_poly: Poly, integrand: Expr): + denom = sqrt(a+b*x+c*x**2) + deg = numer_poly.degree() + if deg <= 1: + # integrand == (d+e*x)/sqrt(a+b*x+c*x**2) + e, d = numer_poly.all_coeffs() if deg == 1 else (S.Zero, numer_poly.as_expr()) + # rewrite numerator to A*(2*c*x+b) + B + A = e/(2*c) + B = d-A*b + pre_substitute = (2*c*x+b)/denom + constant_step: Rule | None = None + linear_step: Rule | None = None + if A != 0: + u = Dummy("u") + pow_rule = PowerRule(1/sqrt(u), u, u, -S.Half) + linear_step = URule(pre_substitute, x, u, a+b*x+c*x**2, pow_rule) + if A != 1: + linear_step = ConstantTimesRule(A*pre_substitute, x, A, pre_substitute, linear_step) + if B != 0: + constant_step = inverse_trig_rule(IntegralInfo(1/denom, x), degenerate=False) + if B != 1: + constant_step = ConstantTimesRule(B/denom, x, B, 1/denom, constant_step) # type: ignore + if linear_step and constant_step: + add = Add(A*pre_substitute, B/denom, evaluate=False) + step: Rule | None = RewriteRule(integrand, x, add, AddRule(add, x, [linear_step, constant_step])) + else: + step = linear_step or constant_step + else: + coeffs = numer_poly.all_coeffs() + step = SqrtQuadraticDenomRule(integrand, x, a, b, c, coeffs) + return step + + if n > 0: # rewrite poly * sqrt(s)**(2*k-1) to poly*s**k / sqrt(s) + numer_poly = f_poly * (a+b*x+c*x**2)**((n+1)/2) + rewritten = numer_poly.as_expr()/sqrt(a+b*x+c*x**2) + substep = sqrt_quadratic_denom_rule(numer_poly, rewritten) + generic_step = RewriteRule(integrand, x, rewritten, substep) + elif n == -1: + generic_step = sqrt_quadratic_denom_rule(f_poly, integrand) + else: + return # todo: handle n < -1 case + return _add_degenerate_step(generic_cond, generic_step, degenerate_step) + + +def hyperbolic_rule(integral: tuple[Expr, Symbol]): + integrand, symbol = integral + if isinstance(integrand, HyperbolicFunction) and integrand.args[0] == symbol: + if integrand.func == sinh: + return SinhRule(integrand, symbol) + if integrand.func == cosh: + return CoshRule(integrand, symbol) + u = Dummy('u') + if integrand.func == tanh: + rewritten = sinh(symbol)/cosh(symbol) + return RewriteRule(integrand, symbol, rewritten, + URule(rewritten, symbol, u, cosh(symbol), ReciprocalRule(1/u, u, u))) + if integrand.func == coth: + rewritten = cosh(symbol)/sinh(symbol) + return RewriteRule(integrand, symbol, rewritten, + URule(rewritten, symbol, u, sinh(symbol), ReciprocalRule(1/u, u, u))) + else: + rewritten = integrand.rewrite(tanh) + if integrand.func == sech: + return RewriteRule(integrand, symbol, rewritten, + URule(rewritten, symbol, u, tanh(symbol/2), + ArctanRule(2/(u**2 + 1), u, S(2), S.One, S.One))) + if integrand.func == csch: + return RewriteRule(integrand, symbol, rewritten, + URule(rewritten, symbol, u, tanh(symbol/2), + ReciprocalRule(1/u, u, u))) + +@cacheit +def make_wilds(symbol): + a = Wild('a', exclude=[symbol]) + b = Wild('b', exclude=[symbol]) + m = Wild('m', exclude=[symbol], properties=[lambda n: isinstance(n, Integer)]) + n = Wild('n', exclude=[symbol], properties=[lambda n: isinstance(n, Integer)]) + + return a, b, m, n + +@cacheit +def sincos_pattern(symbol): + a, b, m, n = make_wilds(symbol) + pattern = sin(a*symbol)**m * cos(b*symbol)**n + + return pattern, a, b, m, n + +@cacheit +def tansec_pattern(symbol): + a, b, m, n = make_wilds(symbol) + pattern = tan(a*symbol)**m * sec(b*symbol)**n + + return pattern, a, b, m, n + +@cacheit +def cotcsc_pattern(symbol): + a, b, m, n = make_wilds(symbol) + pattern = cot(a*symbol)**m * csc(b*symbol)**n + + return pattern, a, b, m, n + +@cacheit +def heaviside_pattern(symbol): + m = Wild('m', exclude=[symbol]) + b = Wild('b', exclude=[symbol]) + g = Wild('g') + pattern = Heaviside(m*symbol + b) * g + + return pattern, m, b, g + +def uncurry(func): + def uncurry_rl(args): + return func(*args) + return uncurry_rl + +def trig_rewriter(rewrite): + def trig_rewriter_rl(args): + a, b, m, n, integrand, symbol = args + rewritten = rewrite(a, b, m, n, integrand, symbol) + if rewritten != integrand: + return RewriteRule(integrand, symbol, rewritten, integral_steps(rewritten, symbol)) + return trig_rewriter_rl + +sincos_botheven_condition = uncurry( + lambda a, b, m, n, i, s: m.is_even and n.is_even and + m.is_nonnegative and n.is_nonnegative) + +sincos_botheven = trig_rewriter( + lambda a, b, m, n, i, symbol: ( (((1 - cos(2*a*symbol)) / 2) ** (m / 2)) * + (((1 + cos(2*b*symbol)) / 2) ** (n / 2)) )) + +sincos_sinodd_condition = uncurry(lambda a, b, m, n, i, s: m.is_odd and m >= 3) + +sincos_sinodd = trig_rewriter( + lambda a, b, m, n, i, symbol: ( (1 - cos(a*symbol)**2)**((m - 1) / 2) * + sin(a*symbol) * + cos(b*symbol) ** n)) + +sincos_cosodd_condition = uncurry(lambda a, b, m, n, i, s: n.is_odd and n >= 3) + +sincos_cosodd = trig_rewriter( + lambda a, b, m, n, i, symbol: ( (1 - sin(b*symbol)**2)**((n - 1) / 2) * + cos(b*symbol) * + sin(a*symbol) ** m)) + +tansec_seceven_condition = uncurry(lambda a, b, m, n, i, s: n.is_even and n >= 4) +tansec_seceven = trig_rewriter( + lambda a, b, m, n, i, symbol: ( (1 + tan(b*symbol)**2) ** (n/2 - 1) * + sec(b*symbol)**2 * + tan(a*symbol) ** m )) + +tansec_tanodd_condition = uncurry(lambda a, b, m, n, i, s: m.is_odd) +tansec_tanodd = trig_rewriter( + lambda a, b, m, n, i, symbol: ( (sec(a*symbol)**2 - 1) ** ((m - 1) / 2) * + tan(a*symbol) * + sec(b*symbol) ** n )) + +tan_tansquared_condition = uncurry(lambda a, b, m, n, i, s: m == 2 and n == 0) +tan_tansquared = trig_rewriter( + lambda a, b, m, n, i, symbol: ( sec(a*symbol)**2 - 1)) + +cotcsc_csceven_condition = uncurry(lambda a, b, m, n, i, s: n.is_even and n >= 4) +cotcsc_csceven = trig_rewriter( + lambda a, b, m, n, i, symbol: ( (1 + cot(b*symbol)**2) ** (n/2 - 1) * + csc(b*symbol)**2 * + cot(a*symbol) ** m )) + +cotcsc_cotodd_condition = uncurry(lambda a, b, m, n, i, s: m.is_odd) +cotcsc_cotodd = trig_rewriter( + lambda a, b, m, n, i, symbol: ( (csc(a*symbol)**2 - 1) ** ((m - 1) / 2) * + cot(a*symbol) * + csc(b*symbol) ** n )) + +def trig_sincos_rule(integral): + integrand, symbol = integral + + if any(integrand.has(f) for f in (sin, cos)): + pattern, a, b, m, n = sincos_pattern(symbol) + match = integrand.match(pattern) + if not match: + return + + return multiplexer({ + sincos_botheven_condition: sincos_botheven, + sincos_sinodd_condition: sincos_sinodd, + sincos_cosodd_condition: sincos_cosodd + })(tuple( + [match.get(i, S.Zero) for i in (a, b, m, n)] + + [integrand, symbol])) + +def trig_tansec_rule(integral): + integrand, symbol = integral + + integrand = integrand.subs({ + 1 / cos(symbol): sec(symbol) + }) + + if any(integrand.has(f) for f in (tan, sec)): + pattern, a, b, m, n = tansec_pattern(symbol) + match = integrand.match(pattern) + if not match: + return + + return multiplexer({ + tansec_tanodd_condition: tansec_tanodd, + tansec_seceven_condition: tansec_seceven, + tan_tansquared_condition: tan_tansquared + })(tuple( + [match.get(i, S.Zero) for i in (a, b, m, n)] + + [integrand, symbol])) + +def trig_cotcsc_rule(integral): + integrand, symbol = integral + integrand = integrand.subs({ + 1 / sin(symbol): csc(symbol), + 1 / tan(symbol): cot(symbol), + cos(symbol) / tan(symbol): cot(symbol) + }) + + if any(integrand.has(f) for f in (cot, csc)): + pattern, a, b, m, n = cotcsc_pattern(symbol) + match = integrand.match(pattern) + if not match: + return + + return multiplexer({ + cotcsc_cotodd_condition: cotcsc_cotodd, + cotcsc_csceven_condition: cotcsc_csceven + })(tuple( + [match.get(i, S.Zero) for i in (a, b, m, n)] + + [integrand, symbol])) + +def trig_sindouble_rule(integral): + integrand, symbol = integral + a = Wild('a', exclude=[sin(2*symbol)]) + match = integrand.match(sin(2*symbol)*a) + if match: + sin_double = 2*sin(symbol)*cos(symbol)/sin(2*symbol) + return integral_steps(integrand * sin_double, symbol) + +def trig_powers_products_rule(integral): + return do_one(null_safe(trig_sincos_rule), + null_safe(trig_tansec_rule), + null_safe(trig_cotcsc_rule), + null_safe(trig_sindouble_rule))(integral) + +def trig_substitution_rule(integral): + integrand, symbol = integral + A = Wild('a', exclude=[0, symbol]) + B = Wild('b', exclude=[0, symbol]) + theta = Dummy("theta") + target_pattern = A + B*symbol**2 + + matches = integrand.find(target_pattern) + for expr in matches: + match = expr.match(target_pattern) + a = match.get(A, S.Zero) + b = match.get(B, S.Zero) + + a_positive = ((a.is_number and a > 0) or a.is_positive) + b_positive = ((b.is_number and b > 0) or b.is_positive) + a_negative = ((a.is_number and a < 0) or a.is_negative) + b_negative = ((b.is_number and b < 0) or b.is_negative) + x_func = None + if a_positive and b_positive: + # a**2 + b*x**2. Assume sec(theta) > 0, -pi/2 < theta < pi/2 + x_func = (sqrt(a)/sqrt(b)) * tan(theta) + # Do not restrict the domain: tan(theta) takes on any real + # value on the interval -pi/2 < theta < pi/2 so x takes on + # any value + restriction = True + elif a_positive and b_negative: + # a**2 - b*x**2. Assume cos(theta) > 0, -pi/2 < theta < pi/2 + constant = sqrt(a)/sqrt(-b) + x_func = constant * sin(theta) + restriction = And(symbol > -constant, symbol < constant) + elif a_negative and b_positive: + # b*x**2 - a**2. Assume sin(theta) > 0, 0 < theta < pi + constant = sqrt(-a)/sqrt(b) + x_func = constant * sec(theta) + restriction = And(symbol > -constant, symbol < constant) + if x_func: + # Manually simplify sqrt(trig(theta)**2) to trig(theta) + # Valid due to assumed domain restriction + substitutions = {} + for f in [sin, cos, tan, + sec, csc, cot]: + substitutions[sqrt(f(theta)**2)] = f(theta) + substitutions[sqrt(f(theta)**(-2))] = 1/f(theta) + + replaced = integrand.subs(symbol, x_func).trigsimp() + replaced = manual_subs(replaced, substitutions) + if not replaced.has(symbol): + replaced *= manual_diff(x_func, theta) + replaced = replaced.trigsimp() + secants = replaced.find(1/cos(theta)) + if secants: + replaced = replaced.xreplace({ + 1/cos(theta): sec(theta) + }) + + substep = integral_steps(replaced, theta) + if not substep.contains_dont_know(): + return TrigSubstitutionRule(integrand, symbol, + theta, x_func, replaced, substep, restriction) + +def heaviside_rule(integral): + integrand, symbol = integral + pattern, m, b, g = heaviside_pattern(symbol) + match = integrand.match(pattern) + if match and 0 != match[g]: + # f = Heaviside(m*x + b)*g + substep = integral_steps(match[g], symbol) + m, b = match[m], match[b] + return HeavisideRule(integrand, symbol, m*symbol + b, -b/m, substep) + + +def dirac_delta_rule(integral: IntegralInfo): + integrand, x = integral + if len(integrand.args) == 1: + n = S.Zero + else: + n = integrand.args[1] # type: ignore + if not n.is_Integer or n < 0: + return + a, b = Wild('a', exclude=[x]), Wild('b', exclude=[x, 0]) + match = integrand.args[0].match(a+b*x) + if not match: + return + a, b = match[a], match[b] + generic_cond = Ne(b, 0) + if generic_cond is S.true: + degenerate_step = None + else: + degenerate_step = ConstantRule(DiracDelta(a, n), x) + generic_step = DiracDeltaRule(integrand, x, n, a, b) + return _add_degenerate_step(generic_cond, generic_step, degenerate_step) + + +def substitution_rule(integral): + integrand, symbol = integral + + u_var = Dummy("u") + substitutions = find_substitutions(integrand, symbol, u_var) + count = 0 + if substitutions: + debug("List of Substitution Rules") + ways = [] + for u_func, c, substituted in substitutions: + subrule = integral_steps(substituted, u_var) + count = count + 1 + debug("Rule {}: {}".format(count, subrule)) + + if subrule.contains_dont_know(): + continue + + if simplify(c - 1) != 0: + _, denom = c.as_numer_denom() + if subrule: + subrule = ConstantTimesRule(c * substituted, u_var, c, substituted, subrule) + + if denom.free_symbols: + piecewise = [] + could_be_zero = [] + + if isinstance(denom, Mul): + could_be_zero = denom.args + else: + could_be_zero.append(denom) + + for expr in could_be_zero: + if not fuzzy_not(expr.is_zero): + substep = integral_steps(manual_subs(integrand, expr, 0), symbol) + + if substep: + piecewise.append(( + substep, + Eq(expr, 0) + )) + piecewise.append((subrule, True)) + subrule = PiecewiseRule(substituted, symbol, piecewise) + + ways.append(URule(integrand, symbol, u_var, u_func, subrule)) + + if len(ways) > 1: + return AlternativeRule(integrand, symbol, ways) + elif ways: + return ways[0] + + +partial_fractions_rule = rewriter( + lambda integrand, symbol: integrand.is_rational_function(), + lambda integrand, symbol: integrand.apart(symbol)) + +cancel_rule = rewriter( + # lambda integrand, symbol: integrand.is_algebraic_expr(), + # lambda integrand, symbol: isinstance(integrand, Mul), + lambda integrand, symbol: True, + lambda integrand, symbol: integrand.cancel()) + +distribute_expand_rule = rewriter( + lambda integrand, symbol: ( + isinstance(integrand, (Pow, Mul)) or all(arg.is_Pow or arg.is_polynomial(symbol) for arg in integrand.args)), + lambda integrand, symbol: integrand.expand()) + +trig_expand_rule = rewriter( + # If there are trig functions with different arguments, expand them + lambda integrand, symbol: ( + len({a.args[0] for a in integrand.atoms(TrigonometricFunction)}) > 1), + lambda integrand, symbol: integrand.expand(trig=True)) + +def derivative_rule(integral): + integrand = integral[0] + diff_variables = integrand.variables + undifferentiated_function = integrand.expr + integrand_variables = undifferentiated_function.free_symbols + + if integral.symbol in integrand_variables: + if integral.symbol in diff_variables: + return DerivativeRule(*integral) + else: + return DontKnowRule(integrand, integral.symbol) + else: + return ConstantRule(*integral) + +def rewrites_rule(integral): + integrand, symbol = integral + + if integrand.match(1/cos(symbol)): + rewritten = integrand.subs(1/cos(symbol), sec(symbol)) + return RewriteRule(integrand, symbol, rewritten, integral_steps(rewritten, symbol)) + +def fallback_rule(integral): + return DontKnowRule(*integral) + +# Cache is used to break cyclic integrals. +# Need to use the same dummy variable in cached expressions for them to match. +# Also record "u" of integration by parts, to avoid infinite repetition. +_integral_cache: dict[Expr, Expr | None] = {} +_parts_u_cache: dict[Expr, int] = defaultdict(int) +_cache_dummy = Dummy("z") + +def integral_steps(integrand, symbol, **options): + """Returns the steps needed to compute an integral. + + Explanation + =========== + + This function attempts to mirror what a student would do by hand as + closely as possible. + + SymPy Gamma uses this to provide a step-by-step explanation of an + integral. The code it uses to format the results of this function can be + found at + https://github.com/sympy/sympy_gamma/blob/master/app/logic/intsteps.py. + + Examples + ======== + + >>> from sympy import exp, sin + >>> from sympy.integrals.manualintegrate import integral_steps + >>> from sympy.abc import x + >>> print(repr(integral_steps(exp(x) / (1 + exp(2 * x)), x))) \ + # doctest: +NORMALIZE_WHITESPACE + URule(integrand=exp(x)/(exp(2*x) + 1), variable=x, u_var=_u, u_func=exp(x), + substep=ArctanRule(integrand=1/(_u**2 + 1), variable=_u, a=1, b=1, c=1)) + >>> print(repr(integral_steps(sin(x), x))) \ + # doctest: +NORMALIZE_WHITESPACE + SinRule(integrand=sin(x), variable=x) + >>> print(repr(integral_steps((x**2 + 3)**2, x))) \ + # doctest: +NORMALIZE_WHITESPACE + RewriteRule(integrand=(x**2 + 3)**2, variable=x, rewritten=x**4 + 6*x**2 + 9, + substep=AddRule(integrand=x**4 + 6*x**2 + 9, variable=x, + substeps=[PowerRule(integrand=x**4, variable=x, base=x, exp=4), + ConstantTimesRule(integrand=6*x**2, variable=x, constant=6, other=x**2, + substep=PowerRule(integrand=x**2, variable=x, base=x, exp=2)), + ConstantRule(integrand=9, variable=x)])) + + Returns + ======= + + rule : Rule + The first step; most rules have substeps that must also be + considered. These substeps can be evaluated using ``manualintegrate`` + to obtain a result. + + """ + cachekey = integrand.xreplace({symbol: _cache_dummy}) + if cachekey in _integral_cache: + if _integral_cache[cachekey] is None: + # Stop this attempt, because it leads around in a loop + return DontKnowRule(integrand, symbol) + else: + # TODO: This is for future development, as currently + # _integral_cache gets no values other than None + return (_integral_cache[cachekey].xreplace(_cache_dummy, symbol), + symbol) + else: + _integral_cache[cachekey] = None + + integral = IntegralInfo(integrand, symbol) + + def key(integral): + integrand = integral.integrand + + if symbol not in integrand.free_symbols: + return Number + for cls in (Symbol, TrigonometricFunction, OrthogonalPolynomial): + if isinstance(integrand, cls): + return cls + return type(integrand) + + def integral_is_subclass(*klasses): + def _integral_is_subclass(integral): + k = key(integral) + return k and issubclass(k, klasses) + return _integral_is_subclass + + result = do_one( + null_safe(special_function_rule), + null_safe(switch(key, { + Pow: do_one(null_safe(power_rule), null_safe(inverse_trig_rule), + null_safe(sqrt_linear_rule), + null_safe(quadratic_denom_rule)), + Symbol: power_rule, + exp: exp_rule, + Add: add_rule, + Mul: do_one(null_safe(mul_rule), null_safe(trig_product_rule), + null_safe(heaviside_rule), null_safe(quadratic_denom_rule), + null_safe(sqrt_linear_rule), + null_safe(sqrt_quadratic_rule)), + Derivative: derivative_rule, + TrigonometricFunction: trig_rule, + Heaviside: heaviside_rule, + DiracDelta: dirac_delta_rule, + OrthogonalPolynomial: orthogonal_poly_rule, + Number: constant_rule + })), + do_one( + null_safe(trig_rule), + null_safe(hyperbolic_rule), + null_safe(alternatives( + rewrites_rule, + substitution_rule, + condition( + integral_is_subclass(Mul, Pow), + partial_fractions_rule), + condition( + integral_is_subclass(Mul, Pow), + cancel_rule), + condition( + integral_is_subclass(Mul, log, + *inverse_trig_functions), + parts_rule), + condition( + integral_is_subclass(Mul, Pow), + distribute_expand_rule), + trig_powers_products_rule, + trig_expand_rule + )), + null_safe(condition(integral_is_subclass(Mul, Pow), nested_pow_rule)), + null_safe(trig_substitution_rule) + ), + fallback_rule)(integral) + del _integral_cache[cachekey] + return result + + +def manualintegrate(f, var): + """manualintegrate(f, var) + + Explanation + =========== + + Compute indefinite integral of a single variable using an algorithm that + resembles what a student would do by hand. + + Unlike :func:`~.integrate`, var can only be a single symbol. + + Examples + ======== + + >>> from sympy import sin, cos, tan, exp, log, integrate + >>> from sympy.integrals.manualintegrate import manualintegrate + >>> from sympy.abc import x + >>> manualintegrate(1 / x, x) + log(x) + >>> integrate(1/x) + log(x) + >>> manualintegrate(log(x), x) + x*log(x) - x + >>> integrate(log(x)) + x*log(x) - x + >>> manualintegrate(exp(x) / (1 + exp(2 * x)), x) + atan(exp(x)) + >>> integrate(exp(x) / (1 + exp(2 * x))) + RootSum(4*_z**2 + 1, Lambda(_i, _i*log(2*_i + exp(x)))) + >>> manualintegrate(cos(x)**4 * sin(x), x) + -cos(x)**5/5 + >>> integrate(cos(x)**4 * sin(x), x) + -cos(x)**5/5 + >>> manualintegrate(cos(x)**4 * sin(x)**3, x) + cos(x)**7/7 - cos(x)**5/5 + >>> integrate(cos(x)**4 * sin(x)**3, x) + cos(x)**7/7 - cos(x)**5/5 + >>> manualintegrate(tan(x), x) + -log(cos(x)) + >>> integrate(tan(x), x) + -log(cos(x)) + + See Also + ======== + + sympy.integrals.integrals.integrate + sympy.integrals.integrals.Integral.doit + sympy.integrals.integrals.Integral + """ + result = integral_steps(f, var).eval() + # Clear the cache of u-parts + _parts_u_cache.clear() + # If we got Piecewise with two parts, put generic first + if isinstance(result, Piecewise) and len(result.args) == 2: + cond = result.args[0][1] + if isinstance(cond, Eq) and result.args[1][1] == True: + result = result.func( + (result.args[1][0], Ne(*cond.args)), + (result.args[0][0], True)) + return result diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/meijerint.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/meijerint.py new file mode 100644 index 0000000000000000000000000000000000000000..89d8401c7eee0147df2e824dc1dc50b59ca7f0be --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/meijerint.py @@ -0,0 +1,2191 @@ +""" +Integrate functions by rewriting them as Meijer G-functions. + +There are three user-visible functions that can be used by other parts of the +sympy library to solve various integration problems: + +- meijerint_indefinite +- meijerint_definite +- meijerint_inversion + +They can be used to compute, respectively, indefinite integrals, definite +integrals over intervals of the real line, and inverse laplace-type integrals +(from c-I*oo to c+I*oo). See the respective docstrings for details. + +The main references for this are: + +[L] Luke, Y. L. (1969), The Special Functions and Their Approximations, + Volume 1 + +[R] Kelly B. Roach. Meijer G Function Representations. + In: Proceedings of the 1997 International Symposium on Symbolic and + Algebraic Computation, pages 205-211, New York, 1997. ACM. + +[P] A. P. Prudnikov, Yu. A. Brychkov and O. I. Marichev (1990). + Integrals and Series: More Special Functions, Vol. 3,. + Gordon and Breach Science Publisher +""" + +from __future__ import annotations +import itertools + +from sympy import SYMPY_DEBUG +from sympy.core import S, Expr +from sympy.core.add import Add +from sympy.core.basic import Basic +from sympy.core.cache import cacheit +from sympy.core.containers import Tuple +from sympy.core.exprtools import factor_terms +from sympy.core.function import (expand, expand_mul, expand_power_base, + expand_trig, Function) +from sympy.core.mul import Mul +from sympy.core.intfunc import ilcm +from sympy.core.numbers import Rational, pi +from sympy.core.relational import Eq, Ne, _canonical_coeff +from sympy.core.sorting import default_sort_key, ordered +from sympy.core.symbol import Dummy, symbols, Wild, Symbol +from sympy.core.sympify import sympify +from sympy.functions.combinatorial.factorials import factorial +from sympy.functions.elementary.complexes import (re, im, arg, Abs, sign, + unpolarify, polarify, polar_lift, principal_branch, unbranched_argument, + periodic_argument) +from sympy.functions.elementary.exponential import exp, exp_polar, log +from sympy.functions.elementary.integers import ceiling +from sympy.functions.elementary.hyperbolic import (cosh, sinh, + _rewrite_hyperbolics_as_exp, HyperbolicFunction) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise, piecewise_fold +from sympy.functions.elementary.trigonometric import (cos, sin, sinc, + TrigonometricFunction) +from sympy.functions.special.bessel import besselj, bessely, besseli, besselk +from sympy.functions.special.delta_functions import DiracDelta, Heaviside +from sympy.functions.special.elliptic_integrals import elliptic_k, elliptic_e +from sympy.functions.special.error_functions import (erf, erfc, erfi, Ei, + expint, Si, Ci, Shi, Chi, fresnels, fresnelc) +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import hyper, meijerg +from sympy.functions.special.singularity_functions import SingularityFunction +from .integrals import Integral +from sympy.logic.boolalg import And, Or, BooleanAtom, Not, BooleanFunction +from sympy.polys import cancel, factor +from sympy.utilities.iterables import multiset_partitions +from sympy.utilities.misc import debug as _debug +from sympy.utilities.misc import debugf as _debugf + +# keep this at top for easy reference +z = Dummy('z') + + +def _has(res, *f): + # return True if res has f; in the case of Piecewise + # only return True if *all* pieces have f + res = piecewise_fold(res) + if getattr(res, 'is_Piecewise', False): + return all(_has(i, *f) for i in res.args) + return res.has(*f) + + +def _create_lookup_table(table): + """ Add formulae for the function -> meijerg lookup table. """ + def wild(n): + return Wild(n, exclude=[z]) + p, q, a, b, c = list(map(wild, 'pqabc')) + n = Wild('n', properties=[lambda x: x.is_Integer and x > 0]) + t = p*z**q + + def add(formula, an, ap, bm, bq, arg=t, fac=S.One, cond=True, hint=True): + table.setdefault(_mytype(formula, z), []).append((formula, + [(fac, meijerg(an, ap, bm, bq, arg))], cond, hint)) + + def addi(formula, inst, cond, hint=True): + table.setdefault( + _mytype(formula, z), []).append((formula, inst, cond, hint)) + + def constant(a): + return [(a, meijerg([1], [], [], [0], z)), + (a, meijerg([], [1], [0], [], z))] + table[()] = [(a, constant(a), True, True)] + + # [P], Section 8. + class IsNonPositiveInteger(Function): + + @classmethod + def eval(cls, arg): + arg = unpolarify(arg) + if arg.is_Integer is True: + return arg <= 0 + + # Section 8.4.2 + # TODO this needs more polar_lift (c/f entry for exp) + add(Heaviside(t - b)*(t - b)**(a - 1), [a], [], [], [0], t/b, + gamma(a)*b**(a - 1), And(b > 0)) + add(Heaviside(b - t)*(b - t)**(a - 1), [], [a], [0], [], t/b, + gamma(a)*b**(a - 1), And(b > 0)) + add(Heaviside(z - (b/p)**(1/q))*(t - b)**(a - 1), [a], [], [], [0], t/b, + gamma(a)*b**(a - 1), And(b > 0)) + add(Heaviside((b/p)**(1/q) - z)*(b - t)**(a - 1), [], [a], [0], [], t/b, + gamma(a)*b**(a - 1), And(b > 0)) + add((b + t)**(-a), [1 - a], [], [0], [], t/b, b**(-a)/gamma(a), + hint=Not(IsNonPositiveInteger(a))) + add(Abs(b - t)**(-a), [1 - a], [(1 - a)/2], [0], [(1 - a)/2], t/b, + 2*sin(pi*a/2)*gamma(1 - a)*Abs(b)**(-a), re(a) < 1) + add((t**a - b**a)/(t - b), [0, a], [], [0, a], [], t/b, + b**(a - 1)*sin(a*pi)/pi) + + # 12 + def A1(r, sign, nu): + return pi**Rational(-1, 2)*(-sign*nu/2)**(1 - 2*r) + + def tmpadd(r, sgn): + # XXX the a**2 is bad for matching + add((sqrt(a**2 + t) + sgn*a)**b/(a**2 + t)**r, + [(1 + b)/2, 1 - 2*r + b/2], [], + [(b - sgn*b)/2], [(b + sgn*b)/2], t/a**2, + a**(b - 2*r)*A1(r, sgn, b)) + tmpadd(0, 1) + tmpadd(0, -1) + tmpadd(S.Half, 1) + tmpadd(S.Half, -1) + + # 13 + def tmpadd(r, sgn): + add((sqrt(a + p*z**q) + sgn*sqrt(p)*z**(q/2))**b/(a + p*z**q)**r, + [1 - r + sgn*b/2], [1 - r - sgn*b/2], [0, S.Half], [], + p*z**q/a, a**(b/2 - r)*A1(r, sgn, b)) + tmpadd(0, 1) + tmpadd(0, -1) + tmpadd(S.Half, 1) + tmpadd(S.Half, -1) + # (those after look obscure) + + # Section 8.4.3 + add(exp(polar_lift(-1)*t), [], [], [0], []) + + # TODO can do sin^n, sinh^n by expansion ... where? + # 8.4.4 (hyperbolic functions) + add(sinh(t), [], [1], [S.Half], [1, 0], t**2/4, pi**Rational(3, 2)) + add(cosh(t), [], [S.Half], [0], [S.Half, S.Half], t**2/4, pi**Rational(3, 2)) + + # Section 8.4.5 + # TODO can do t + a. but can also do by expansion... (XXX not really) + add(sin(t), [], [], [S.Half], [0], t**2/4, sqrt(pi)) + add(cos(t), [], [], [0], [S.Half], t**2/4, sqrt(pi)) + + # Section 8.4.6 (sinc function) + add(sinc(t), [], [], [0], [Rational(-1, 2)], t**2/4, sqrt(pi)/2) + + # Section 8.5.5 + def make_log1(subs): + N = subs[n] + return [(S.NegativeOne**N*factorial(N), + meijerg([], [1]*(N + 1), [0]*(N + 1), [], t))] + + def make_log2(subs): + N = subs[n] + return [(factorial(N), + meijerg([1]*(N + 1), [], [], [0]*(N + 1), t))] + # TODO these only hold for positive p, and can be made more general + # but who uses log(x)*Heaviside(a-x) anyway ... + # TODO also it would be nice to derive them recursively ... + addi(log(t)**n*Heaviside(1 - t), make_log1, True) + addi(log(t)**n*Heaviside(t - 1), make_log2, True) + + def make_log3(subs): + return make_log1(subs) + make_log2(subs) + addi(log(t)**n, make_log3, True) + addi(log(t + a), + constant(log(a)) + [(S.One, meijerg([1, 1], [], [1], [0], t/a))], + True) + addi(log(Abs(t - a)), constant(log(Abs(a))) + + [(pi, meijerg([1, 1], [S.Half], [1], [0, S.Half], t/a))], + True) + # TODO log(x)/(x+a) and log(x)/(x-1) can also be done. should they + # be derivable? + # TODO further formulae in this section seem obscure + + # Sections 8.4.9-10 + # TODO + + # Section 8.4.11 + addi(Ei(t), + constant(-S.ImaginaryUnit*pi) + [(S.NegativeOne, meijerg([], [1], [0, 0], [], + t*polar_lift(-1)))], + True) + + # Section 8.4.12 + add(Si(t), [1], [], [S.Half], [0, 0], t**2/4, sqrt(pi)/2) + add(Ci(t), [], [1], [0, 0], [S.Half], t**2/4, -sqrt(pi)/2) + + # Section 8.4.13 + add(Shi(t), [S.Half], [], [0], [Rational(-1, 2), Rational(-1, 2)], polar_lift(-1)*t**2/4, + t*sqrt(pi)/4) + add(Chi(t), [], [S.Half, 1], [0, 0], [S.Half, S.Half], t**2/4, - + pi**S('3/2')/2) + + # generalized exponential integral + add(expint(a, t), [], [a], [a - 1, 0], [], t) + + # Section 8.4.14 + add(erf(t), [1], [], [S.Half], [0], t**2, 1/sqrt(pi)) + # TODO exp(-x)*erf(I*x) does not work + add(erfc(t), [], [1], [0, S.Half], [], t**2, 1/sqrt(pi)) + # This formula for erfi(z) yields a wrong(?) minus sign + #add(erfi(t), [1], [], [S.Half], [0], -t**2, I/sqrt(pi)) + add(erfi(t), [S.Half], [], [0], [Rational(-1, 2)], -t**2, t/sqrt(pi)) + + # Fresnel Integrals + add(fresnels(t), [1], [], [Rational(3, 4)], [0, Rational(1, 4)], pi**2*t**4/16, S.Half) + add(fresnelc(t), [1], [], [Rational(1, 4)], [0, Rational(3, 4)], pi**2*t**4/16, S.Half) + + ##### bessel-type functions ##### + # Section 8.4.19 + add(besselj(a, t), [], [], [a/2], [-a/2], t**2/4) + + # all of the following are derivable + #add(sin(t)*besselj(a, t), [Rational(1, 4), Rational(3, 4)], [], [(1+a)/2], + # [-a/2, a/2, (1-a)/2], t**2, 1/sqrt(2)) + #add(cos(t)*besselj(a, t), [Rational(1, 4), Rational(3, 4)], [], [a/2], + # [-a/2, (1+a)/2, (1-a)/2], t**2, 1/sqrt(2)) + #add(besselj(a, t)**2, [S.Half], [], [a], [-a, 0], t**2, 1/sqrt(pi)) + #add(besselj(a, t)*besselj(b, t), [0, S.Half], [], [(a + b)/2], + # [-(a+b)/2, (a - b)/2, (b - a)/2], t**2, 1/sqrt(pi)) + + # Section 8.4.20 + add(bessely(a, t), [], [-(a + 1)/2], [a/2, -a/2], [-(a + 1)/2], t**2/4) + + # TODO all of the following should be derivable + #add(sin(t)*bessely(a, t), [Rational(1, 4), Rational(3, 4)], [(1 - a - 1)/2], + # [(1 + a)/2, (1 - a)/2], [(1 - a - 1)/2, (1 - 1 - a)/2, (1 - 1 + a)/2], + # t**2, 1/sqrt(2)) + #add(cos(t)*bessely(a, t), [Rational(1, 4), Rational(3, 4)], [(0 - a - 1)/2], + # [(0 + a)/2, (0 - a)/2], [(0 - a - 1)/2, (1 - 0 - a)/2, (1 - 0 + a)/2], + # t**2, 1/sqrt(2)) + #add(besselj(a, t)*bessely(b, t), [0, S.Half], [(a - b - 1)/2], + # [(a + b)/2, (a - b)/2], [(a - b - 1)/2, -(a + b)/2, (b - a)/2], + # t**2, 1/sqrt(pi)) + #addi(bessely(a, t)**2, + # [(2/sqrt(pi), meijerg([], [S.Half, S.Half - a], [0, a, -a], + # [S.Half - a], t**2)), + # (1/sqrt(pi), meijerg([S.Half], [], [a], [-a, 0], t**2))], + # True) + #addi(bessely(a, t)*bessely(b, t), + # [(2/sqrt(pi), meijerg([], [0, S.Half, (1 - a - b)/2], + # [(a + b)/2, (a - b)/2, (b - a)/2, -(a + b)/2], + # [(1 - a - b)/2], t**2)), + # (1/sqrt(pi), meijerg([0, S.Half], [], [(a + b)/2], + # [-(a + b)/2, (a - b)/2, (b - a)/2], t**2))], + # True) + + # Section 8.4.21 ? + # Section 8.4.22 + add(besseli(a, t), [], [(1 + a)/2], [a/2], [-a/2, (1 + a)/2], t**2/4, pi) + # TODO many more formulas. should all be derivable + + # Section 8.4.23 + add(besselk(a, t), [], [], [a/2, -a/2], [], t**2/4, S.Half) + # TODO many more formulas. should all be derivable + + # Complete elliptic integrals K(z) and E(z) + add(elliptic_k(t), [S.Half, S.Half], [], [0], [0], -t, S.Half) + add(elliptic_e(t), [S.Half, 3*S.Half], [], [0], [0], -t, Rational(-1, 2)/2) + + +#################################################################### +# First some helper functions. +#################################################################### + +from sympy.utilities.timeutils import timethis +timeit = timethis('meijerg') + + +def _mytype(f: Basic, x: Symbol) -> tuple[type[Basic], ...]: + """ Create a hashable entity describing the type of f. """ + def key(x: type[Basic]) -> tuple[int, int, str]: + return x.class_key() + + if x not in f.free_symbols: + return () + elif f.is_Function: + return type(f), + return tuple(sorted((t for a in f.args for t in _mytype(a, x)), key=key)) + + +class _CoeffExpValueError(ValueError): + """ + Exception raised by _get_coeff_exp, for internal use only. + """ + pass + + +def _get_coeff_exp(expr, x): + """ + When expr is known to be of the form c*x**b, with c and/or b possibly 1, + return c, b. + + Examples + ======== + + >>> from sympy.abc import x, a, b + >>> from sympy.integrals.meijerint import _get_coeff_exp + >>> _get_coeff_exp(a*x**b, x) + (a, b) + >>> _get_coeff_exp(x, x) + (1, 1) + >>> _get_coeff_exp(2*x, x) + (2, 1) + >>> _get_coeff_exp(x**3, x) + (1, 3) + """ + from sympy.simplify import powsimp + (c, m) = expand_power_base(powsimp(expr)).as_coeff_mul(x) + if not m: + return c, S.Zero + [m] = m + if m.is_Pow: + if m.base != x: + raise _CoeffExpValueError('expr not of form a*x**b') + return c, m.exp + elif m == x: + return c, S.One + else: + raise _CoeffExpValueError('expr not of form a*x**b: %s' % expr) + + +def _exponents(expr, x): + """ + Find the exponents of ``x`` (not including zero) in ``expr``. + + Examples + ======== + + >>> from sympy.integrals.meijerint import _exponents + >>> from sympy.abc import x, y + >>> from sympy import sin + >>> _exponents(x, x) + {1} + >>> _exponents(x**2, x) + {2} + >>> _exponents(x**2 + x, x) + {1, 2} + >>> _exponents(x**3*sin(x + x**y) + 1/x, x) + {-1, 1, 3, y} + """ + def _exponents_(expr, x, res): + if expr == x: + res.update([1]) + return + if expr.is_Pow and expr.base == x: + res.update([expr.exp]) + return + for argument in expr.args: + _exponents_(argument, x, res) + res = set() + _exponents_(expr, x, res) + return res + + +def _functions(expr, x): + """ Find the types of functions in expr, to estimate the complexity. """ + return {e.func for e in expr.atoms(Function) if x in e.free_symbols} + + +def _find_splitting_points(expr, x): + """ + Find numbers a such that a linear substitution x -> x + a would + (hopefully) simplify expr. + + Examples + ======== + + >>> from sympy.integrals.meijerint import _find_splitting_points as fsp + >>> from sympy import sin + >>> from sympy.abc import x + >>> fsp(x, x) + {0} + >>> fsp((x-1)**3, x) + {1} + >>> fsp(sin(x+3)*x, x) + {-3, 0} + """ + p, q = [Wild(n, exclude=[x]) for n in 'pq'] + + def compute_innermost(expr, res): + if not isinstance(expr, Expr): + return + m = expr.match(p*x + q) + if m and m[p] != 0: + res.add(-m[q]/m[p]) + return + if expr.is_Atom: + return + for argument in expr.args: + compute_innermost(argument, res) + innermost = set() + compute_innermost(expr, innermost) + return innermost + + +def _split_mul(f, x): + """ + Split expression ``f`` into fac, po, g, where fac is a constant factor, + po = x**s for some s independent of s, and g is "the rest". + + Examples + ======== + + >>> from sympy.integrals.meijerint import _split_mul + >>> from sympy import sin + >>> from sympy.abc import s, x + >>> _split_mul((3*x)**s*sin(x**2)*x, x) + (3**s, x*x**s, sin(x**2)) + """ + fac = S.One + po = S.One + g = S.One + f = expand_power_base(f) + + args = Mul.make_args(f) + for a in args: + if a == x: + po *= x + elif x not in a.free_symbols: + fac *= a + else: + if a.is_Pow and x not in a.exp.free_symbols: + c, t = a.base.as_coeff_mul(x) + if t != (x,): + c, t = expand_mul(a.base).as_coeff_mul(x) + if t == (x,): + po *= x**a.exp + fac *= unpolarify(polarify(c**a.exp, subs=False)) + continue + g *= a + + return fac, po, g + + +def _mul_args(f): + """ + Return a list ``L`` such that ``Mul(*L) == f``. + + If ``f`` is not a ``Mul`` or ``Pow``, ``L=[f]``. + If ``f=g**n`` for an integer ``n``, ``L=[g]*n``. + If ``f`` is a ``Mul``, ``L`` comes from applying ``_mul_args`` to all factors of ``f``. + """ + args = Mul.make_args(f) + gs = [] + for g in args: + if g.is_Pow and g.exp.is_Integer: + n = g.exp + base = g.base + if n < 0: + n = -n + base = 1/base + gs += [base]*n + else: + gs.append(g) + return gs + + +def _mul_as_two_parts(f): + """ + Find all the ways to split ``f`` into a product of two terms. + Return None on failure. + + Explanation + =========== + + Although the order is canonical from multiset_partitions, this is + not necessarily the best order to process the terms. For example, + if the case of len(gs) == 2 is removed and multiset is allowed to + sort the terms, some tests fail. + + Examples + ======== + + >>> from sympy.integrals.meijerint import _mul_as_two_parts + >>> from sympy import sin, exp, ordered + >>> from sympy.abc import x + >>> list(ordered(_mul_as_two_parts(x*sin(x)*exp(x)))) + [(x, exp(x)*sin(x)), (x*exp(x), sin(x)), (x*sin(x), exp(x))] + """ + + gs = _mul_args(f) + if len(gs) < 2: + return None + if len(gs) == 2: + return [tuple(gs)] + return [(Mul(*x), Mul(*y)) for (x, y) in multiset_partitions(gs, 2)] + + +def _inflate_g(g, n): + """ Return C, h such that h is a G function of argument z**n and + g = C*h. """ + # TODO should this be a method of meijerg? + # See: [L, page 150, equation (5)] + def inflate(params, n): + """ (a1, .., ak) -> (a1/n, (a1+1)/n, ..., (ak + n-1)/n) """ + return [(a + i)/n for a, i in itertools.product(params, range(n))] + v = S(len(g.ap) - len(g.bq)) + C = n**(1 + g.nu + v/2) + C /= (2*pi)**((n - 1)*g.delta) + return C, meijerg(inflate(g.an, n), inflate(g.aother, n), + inflate(g.bm, n), inflate(g.bother, n), + g.argument**n * n**(n*v)) + + +def _flip_g(g): + """ Turn the G function into one of inverse argument + (i.e. G(1/x) -> G'(x)) """ + # See [L], section 5.2 + def tr(l): + return [1 - a for a in l] + return meijerg(tr(g.bm), tr(g.bother), tr(g.an), tr(g.aother), 1/g.argument) + + +def _inflate_fox_h(g, a): + r""" + Let d denote the integrand in the definition of the G function ``g``. + Consider the function H which is defined in the same way, but with + integrand d/Gamma(a*s) (contour conventions as usual). + + If ``a`` is rational, the function H can be written as C*G, for a constant C + and a G-function G. + + This function returns C, G. + """ + if a < 0: + return _inflate_fox_h(_flip_g(g), -a) + p = S(a.p) + q = S(a.q) + # We use the substitution s->qs, i.e. inflate g by q. We are left with an + # extra factor of Gamma(p*s), for which we use Gauss' multiplication + # theorem. + D, g = _inflate_g(g, q) + z = g.argument + D /= (2*pi)**((1 - p)/2)*p**Rational(-1, 2) + z /= p**p + bs = [(n + 1)/p for n in range(p)] + return D, meijerg(g.an, g.aother, g.bm, list(g.bother) + bs, z) + + +_dummies: dict[tuple[str, str], Dummy] = {} + + +def _dummy(name, token, expr, **kwargs): + """ + Return a dummy. This will return the same dummy if the same token+name is + requested more than once, and it is not already in expr. + This is for being cache-friendly. + """ + d = _dummy_(name, token, **kwargs) + if d in expr.free_symbols: + return Dummy(name, **kwargs) + return d + + +def _dummy_(name, token, **kwargs): + """ + Return a dummy associated to name and token. Same effect as declaring + it globally. + """ + if not (name, token) in _dummies: + _dummies[(name, token)] = Dummy(name, **kwargs) + return _dummies[(name, token)] + + +def _is_analytic(f, x): + """ Check if f(x), when expressed using G functions on the positive reals, + will in fact agree with the G functions almost everywhere """ + return not any(x in expr.free_symbols for expr in f.atoms(Heaviside, Abs)) + + +def _condsimp(cond, first=True): + """ + Do naive simplifications on ``cond``. + + Explanation + =========== + + Note that this routine is completely ad-hoc, simplification rules being + added as need arises rather than following any logical pattern. + + Examples + ======== + + >>> from sympy.integrals.meijerint import _condsimp as simp + >>> from sympy import Or, Eq + >>> from sympy.abc import x, y + >>> simp(Or(x < y, Eq(x, y))) + x <= y + """ + if first: + cond = cond.replace(lambda _: _.is_Relational, _canonical_coeff) + first = False + if not isinstance(cond, BooleanFunction): + return cond + p, q, r = symbols('p q r', cls=Wild) + # transforms tests use 0, 4, 5 and 11-14 + # meijer tests use 0, 2, 11, 14 + # joint_rv uses 6, 7 + rules = [ + (Or(p < q, Eq(p, q)), p <= q), # 0 + # The next two obviously are instances of a general pattern, but it is + # easier to spell out the few cases we care about. + (And(Abs(arg(p)) <= pi, Abs(arg(p) - 2*pi) <= pi), + Eq(arg(p) - pi, 0)), # 1 + (And(Abs(2*arg(p) + pi) <= pi, Abs(2*arg(p) - pi) <= pi), + Eq(arg(p), 0)), # 2 + (And(Abs(2*arg(p) + pi) < pi, Abs(2*arg(p) - pi) <= pi), + S.false), # 3 + (And(Abs(arg(p) - pi/2) <= pi/2, Abs(arg(p) + pi/2) <= pi/2), + Eq(arg(p), 0)), # 4 + (And(Abs(arg(p) - pi/2) <= pi/2, Abs(arg(p) + pi/2) < pi/2), + S.false), # 5 + (And(Abs(arg(p**2/2 + 1)) < pi, Ne(Abs(arg(p**2/2 + 1)), pi)), + S.true), # 6 + (Or(Abs(arg(p**2/2 + 1)) < pi, Ne(1/(p**2/2 + 1), 0)), + S.true), # 7 + (And(Abs(unbranched_argument(p)) <= pi, + Abs(unbranched_argument(exp_polar(-2*pi*S.ImaginaryUnit)*p)) <= pi), + Eq(unbranched_argument(exp_polar(-S.ImaginaryUnit*pi)*p), 0)), # 8 + (And(Abs(unbranched_argument(p)) <= pi/2, + Abs(unbranched_argument(exp_polar(-pi*S.ImaginaryUnit)*p)) <= pi/2), + Eq(unbranched_argument(exp_polar(-S.ImaginaryUnit*pi/2)*p), 0)), # 9 + (Or(p <= q, And(p < q, r)), p <= q), # 10 + (Ne(p**2, 1) & (p**2 > 1), p**2 > 1), # 11 + (Ne(1/p, 1) & (cos(Abs(arg(p)))*Abs(p) > 1), Abs(p) > 1), # 12 + (Ne(p, 2) & (cos(Abs(arg(p)))*Abs(p) > 2), Abs(p) > 2), # 13 + ((Abs(arg(p)) < pi/2) & (cos(Abs(arg(p)))*sqrt(Abs(p**2)) > 1), p**2 > 1), # 14 + ] + cond = cond.func(*[_condsimp(_, first) for _ in cond.args]) + change = True + while change: + change = False + for irule, (fro, to) in enumerate(rules): + if fro.func != cond.func: + continue + for n, arg1 in enumerate(cond.args): + if r in fro.args[0].free_symbols: + m = arg1.match(fro.args[1]) + num = 1 + else: + num = 0 + m = arg1.match(fro.args[0]) + if not m: + continue + otherargs = [x.subs(m) for x in fro.args[:num] + fro.args[num + 1:]] + otherlist = [n] + for arg2 in otherargs: + for k, arg3 in enumerate(cond.args): + if k in otherlist: + continue + if arg2 == arg3: + otherlist += [k] + break + if isinstance(arg3, And) and arg2.args[1] == r and \ + isinstance(arg2, And) and arg2.args[0] in arg3.args: + otherlist += [k] + break + if isinstance(arg3, And) and arg2.args[0] == r and \ + isinstance(arg2, And) and arg2.args[1] in arg3.args: + otherlist += [k] + break + if len(otherlist) != len(otherargs) + 1: + continue + newargs = [arg_ for (k, arg_) in enumerate(cond.args) + if k not in otherlist] + [to.subs(m)] + if SYMPY_DEBUG: + if irule not in (0, 2, 4, 5, 6, 7, 11, 12, 13, 14): + print('used new rule:', irule) + cond = cond.func(*newargs) + change = True + break + + # final tweak + def rel_touchup(rel): + if rel.rel_op != '==' or rel.rhs != 0: + return rel + + # handle Eq(*, 0) + LHS = rel.lhs + m = LHS.match(arg(p)**q) + if not m: + m = LHS.match(unbranched_argument(polar_lift(p)**q)) + if not m: + if isinstance(LHS, periodic_argument) and not LHS.args[0].is_polar \ + and LHS.args[1] is S.Infinity: + return (LHS.args[0] > 0) + return rel + return (m[p] > 0) + cond = cond.replace(lambda _: _.is_Relational, rel_touchup) + if SYMPY_DEBUG: + print('_condsimp: ', cond) + return cond + +def _eval_cond(cond): + """ Re-evaluate the conditions. """ + if isinstance(cond, bool): + return cond + return _condsimp(cond.doit()) + +#################################################################### +# Now the "backbone" functions to do actual integration. +#################################################################### + + +def _my_principal_branch(expr, period, full_pb=False): + """ Bring expr nearer to its principal branch by removing superfluous + factors. + This function does *not* guarantee to yield the principal branch, + to avoid introducing opaque principal_branch() objects, + unless full_pb=True. """ + res = principal_branch(expr, period) + if not full_pb: + res = res.replace(principal_branch, lambda x, y: x) + return res + + +def _rewrite_saxena_1(fac, po, g, x): + """ + Rewrite the integral fac*po*g dx, from zero to infinity, as + integral fac*G, where G has argument a*x. Note po=x**s. + Return fac, G. + """ + _, s = _get_coeff_exp(po, x) + a, b = _get_coeff_exp(g.argument, x) + period = g.get_period() + a = _my_principal_branch(a, period) + + # We substitute t = x**b. + C = fac/(Abs(b)*a**((s + 1)/b - 1)) + # Absorb a factor of (at)**((1 + s)/b - 1). + + def tr(l): + return [a + (1 + s)/b - 1 for a in l] + return C, meijerg(tr(g.an), tr(g.aother), tr(g.bm), tr(g.bother), + a*x) + + +def _check_antecedents_1(g, x, helper=False): + r""" + Return a condition under which the mellin transform of g exists. + Any power of x has already been absorbed into the G function, + so this is just $\int_0^\infty g\, dx$. + + See [L, section 5.6.1]. (Note that s=1.) + + If ``helper`` is True, only check if the MT exists at infinity, i.e. if + $\int_1^\infty g\, dx$ exists. + """ + # NOTE if you update these conditions, please update the documentation as well + delta = g.delta + eta, _ = _get_coeff_exp(g.argument, x) + m, n, p, q = S([len(g.bm), len(g.an), len(g.ap), len(g.bq)]) + + if p > q: + def tr(l): + return [1 - x for x in l] + return _check_antecedents_1(meijerg(tr(g.bm), tr(g.bother), + tr(g.an), tr(g.aother), x/eta), + x) + + tmp = [-re(b) < 1 for b in g.bm] + [1 < 1 - re(a) for a in g.an] + cond_3 = And(*tmp) + + tmp += [-re(b) < 1 for b in g.bother] + tmp += [1 < 1 - re(a) for a in g.aother] + cond_3_star = And(*tmp) + + cond_4 = (-re(g.nu) + (q + 1 - p)/2 > q - p) + + def debug(*msg): + _debug(*msg) + + def debugf(string, arg): + _debugf(string, arg) + + debug('Checking antecedents for 1 function:') + debugf(' delta=%s, eta=%s, m=%s, n=%s, p=%s, q=%s', + (delta, eta, m, n, p, q)) + debugf(' ap = %s, %s', (list(g.an), list(g.aother))) + debugf(' bq = %s, %s', (list(g.bm), list(g.bother))) + debugf(' cond_3=%s, cond_3*=%s, cond_4=%s', (cond_3, cond_3_star, cond_4)) + + conds = [] + + # case 1 + case1 = [] + tmp1 = [1 <= n, p < q, 1 <= m] + tmp2 = [1 <= p, 1 <= m, Eq(q, p + 1), Not(And(Eq(n, 0), Eq(m, p + 1)))] + tmp3 = [1 <= p, Eq(q, p)] + for k in range(ceiling(delta/2) + 1): + tmp3 += [Ne(Abs(unbranched_argument(eta)), (delta - 2*k)*pi)] + tmp = [delta > 0, Abs(unbranched_argument(eta)) < delta*pi] + extra = [Ne(eta, 0), cond_3] + if helper: + extra = [] + for t in [tmp1, tmp2, tmp3]: + case1 += [And(*(t + tmp + extra))] + conds += case1 + debug(' case 1:', case1) + + # case 2 + extra = [cond_3] + if helper: + extra = [] + case2 = [And(Eq(n, 0), p + 1 <= m, m <= q, + Abs(unbranched_argument(eta)) < delta*pi, *extra)] + conds += case2 + debug(' case 2:', case2) + + # case 3 + extra = [cond_3, cond_4] + if helper: + extra = [] + case3 = [And(p < q, 1 <= m, delta > 0, Eq(Abs(unbranched_argument(eta)), delta*pi), + *extra)] + case3 += [And(p <= q - 2, Eq(delta, 0), Eq(Abs(unbranched_argument(eta)), 0), *extra)] + conds += case3 + debug(' case 3:', case3) + + # TODO altered cases 4-7 + + # extra case from wofram functions site: + # (reproduced verbatim from Prudnikov, section 2.24.2) + # https://functions.wolfram.com/HypergeometricFunctions/MeijerG/21/02/01/ + case_extra = [] + case_extra += [Eq(p, q), Eq(delta, 0), Eq(unbranched_argument(eta), 0), Ne(eta, 0)] + if not helper: + case_extra += [cond_3] + s = [] + for a, b in zip(g.ap, g.bq): + s += [b - a] + case_extra += [re(Add(*s)) < 0] + case_extra = And(*case_extra) + conds += [case_extra] + debug(' extra case:', [case_extra]) + + case_extra_2 = [And(delta > 0, Abs(unbranched_argument(eta)) < delta*pi)] + if not helper: + case_extra_2 += [cond_3] + case_extra_2 = And(*case_extra_2) + conds += [case_extra_2] + debug(' second extra case:', [case_extra_2]) + + # TODO This leaves only one case from the three listed by Prudnikov. + # Investigate if these indeed cover everything; if so, remove the rest. + + return Or(*conds) + + +def _int0oo_1(g, x): + r""" + Evaluate $\int_0^\infty g\, dx$ using G functions, + assuming the necessary conditions are fulfilled. + + Examples + ======== + + >>> from sympy.abc import a, b, c, d, x, y + >>> from sympy import meijerg + >>> from sympy.integrals.meijerint import _int0oo_1 + >>> _int0oo_1(meijerg([a], [b], [c], [d], x*y), x) + gamma(-a)*gamma(c + 1)/(y*gamma(-d)*gamma(b + 1)) + """ + from sympy.simplify import gammasimp + # See [L, section 5.6.1]. Note that s=1. + eta, _ = _get_coeff_exp(g.argument, x) + res = 1/eta + # XXX TODO we should reduce order first + for b in g.bm: + res *= gamma(b + 1) + for a in g.an: + res *= gamma(1 - a - 1) + for b in g.bother: + res /= gamma(1 - b - 1) + for a in g.aother: + res /= gamma(a + 1) + return gammasimp(unpolarify(res)) + + +def _rewrite_saxena(fac, po, g1, g2, x, full_pb=False): + """ + Rewrite the integral ``fac*po*g1*g2`` from 0 to oo in terms of G + functions with argument ``c*x``. + + Explanation + =========== + + Return C, f1, f2 such that integral C f1 f2 from 0 to infinity equals + integral fac ``po``, ``g1``, ``g2`` from 0 to infinity. + + Examples + ======== + + >>> from sympy.integrals.meijerint import _rewrite_saxena + >>> from sympy.abc import s, t, m + >>> from sympy import meijerg + >>> g1 = meijerg([], [], [0], [], s*t) + >>> g2 = meijerg([], [], [m/2], [-m/2], t**2/4) + >>> r = _rewrite_saxena(1, t**0, g1, g2, t) + >>> r[0] + s/(4*sqrt(pi)) + >>> r[1] + meijerg(((), ()), ((-1/2, 0), ()), s**2*t/4) + >>> r[2] + meijerg(((), ()), ((m/2,), (-m/2,)), t/4) + """ + def pb(g): + a, b = _get_coeff_exp(g.argument, x) + per = g.get_period() + return meijerg(g.an, g.aother, g.bm, g.bother, + _my_principal_branch(a, per, full_pb)*x**b) + + _, s = _get_coeff_exp(po, x) + _, b1 = _get_coeff_exp(g1.argument, x) + _, b2 = _get_coeff_exp(g2.argument, x) + if (b1 < 0) == True: + b1 = -b1 + g1 = _flip_g(g1) + if (b2 < 0) == True: + b2 = -b2 + g2 = _flip_g(g2) + if not b1.is_Rational or not b2.is_Rational: + return + m1, n1 = b1.p, b1.q + m2, n2 = b2.p, b2.q + tau = ilcm(m1*n2, m2*n1) + r1 = tau//(m1*n2) + r2 = tau//(m2*n1) + + C1, g1 = _inflate_g(g1, r1) + C2, g2 = _inflate_g(g2, r2) + g1 = pb(g1) + g2 = pb(g2) + + fac *= C1*C2 + a1, b = _get_coeff_exp(g1.argument, x) + a2, _ = _get_coeff_exp(g2.argument, x) + + # arbitrarily tack on the x**s part to g1 + # TODO should we try both? + exp = (s + 1)/b - 1 + fac = fac/(Abs(b) * a1**exp) + + def tr(l): + return [a + exp for a in l] + g1 = meijerg(tr(g1.an), tr(g1.aother), tr(g1.bm), tr(g1.bother), a1*x) + g2 = meijerg(g2.an, g2.aother, g2.bm, g2.bother, a2*x) + + from sympy.simplify import powdenest + return powdenest(fac, polar=True), g1, g2 + + +def _check_antecedents(g1, g2, x): + """ Return a condition under which the integral theorem applies. """ + # Yes, this is madness. + # XXX TODO this is a testing *nightmare* + # NOTE if you update these conditions, please update the documentation as well + + # The following conditions are found in + # [P], Section 2.24.1 + # + # They are also reproduced (verbatim!) at + # https://functions.wolfram.com/HypergeometricFunctions/MeijerG/21/02/03/ + # + # Note: k=l=r=alpha=1 + sigma, _ = _get_coeff_exp(g1.argument, x) + omega, _ = _get_coeff_exp(g2.argument, x) + s, t, u, v = S([len(g1.bm), len(g1.an), len(g1.ap), len(g1.bq)]) + m, n, p, q = S([len(g2.bm), len(g2.an), len(g2.ap), len(g2.bq)]) + bstar = s + t - (u + v)/2 + cstar = m + n - (p + q)/2 + rho = g1.nu + (u - v)/2 + 1 + mu = g2.nu + (p - q)/2 + 1 + phi = q - p - (v - u) + eta = 1 - (v - u) - mu - rho + psi = (pi*(q - m - n) + Abs(unbranched_argument(omega)))/(q - p) + theta = (pi*(v - s - t) + Abs(unbranched_argument(sigma)))/(v - u) + + _debug('Checking antecedents:') + _debugf(' sigma=%s, s=%s, t=%s, u=%s, v=%s, b*=%s, rho=%s', + (sigma, s, t, u, v, bstar, rho)) + _debugf(' omega=%s, m=%s, n=%s, p=%s, q=%s, c*=%s, mu=%s,', + (omega, m, n, p, q, cstar, mu)) + _debugf(' phi=%s, eta=%s, psi=%s, theta=%s', (phi, eta, psi, theta)) + + def _c1(): + for g in [g1, g2]: + for i, j in itertools.product(g.an, g.bm): + diff = i - j + if diff.is_integer and diff.is_positive: + return False + return True + c1 = _c1() + c2 = And(*[re(1 + i + j) > 0 for i in g1.bm for j in g2.bm]) + c3 = And(*[re(1 + i + j) < 1 + 1 for i in g1.an for j in g2.an]) + c4 = And(*[(p - q)*re(1 + i - 1) - re(mu) > Rational(-3, 2) for i in g1.an]) + c5 = And(*[(p - q)*re(1 + i) - re(mu) > Rational(-3, 2) for i in g1.bm]) + c6 = And(*[(u - v)*re(1 + i - 1) - re(rho) > Rational(-3, 2) for i in g2.an]) + c7 = And(*[(u - v)*re(1 + i) - re(rho) > Rational(-3, 2) for i in g2.bm]) + c8 = (Abs(phi) + 2*re((rho - 1)*(q - p) + (v - u)*(q - p) + (mu - + 1)*(v - u)) > 0) + c9 = (Abs(phi) - 2*re((rho - 1)*(q - p) + (v - u)*(q - p) + (mu - + 1)*(v - u)) > 0) + c10 = (Abs(unbranched_argument(sigma)) < bstar*pi) + c11 = Eq(Abs(unbranched_argument(sigma)), bstar*pi) + c12 = (Abs(unbranched_argument(omega)) < cstar*pi) + c13 = Eq(Abs(unbranched_argument(omega)), cstar*pi) + + # The following condition is *not* implemented as stated on the wolfram + # function site. In the book of Prudnikov there is an additional part + # (the And involving re()). However, I only have this book in russian, and + # I don't read any russian. The following condition is what other people + # have told me it means. + # Worryingly, it is different from the condition implemented in REDUCE. + # The REDUCE implementation: + # https://reduce-algebra.svn.sourceforge.net/svnroot/reduce-algebra/trunk/packages/defint/definta.red + # (search for tst14) + # The Wolfram alpha version: + # https://functions.wolfram.com/HypergeometricFunctions/MeijerG/21/02/03/03/0014/ + z0 = exp(-(bstar + cstar)*pi*S.ImaginaryUnit) + zos = unpolarify(z0*omega/sigma) + zso = unpolarify(z0*sigma/omega) + if zos == 1/zso: + c14 = And(Eq(phi, 0), bstar + cstar <= 1, + Or(Ne(zos, 1), re(mu + rho + v - u) < 1, + re(mu + rho + q - p) < 1)) + else: + def _cond(z): + '''Returns True if abs(arg(1-z)) < pi, avoiding arg(0). + + Explanation + =========== + + If ``z`` is 1 then arg is NaN. This raises a + TypeError on `NaN < pi`. Previously this gave `False` so + this behavior has been hardcoded here but someone should + check if this NaN is more serious! This NaN is triggered by + test_meijerint() in test_meijerint.py: + `meijerint_definite(exp(x), x, 0, I)` + ''' + return z != 1 and Abs(arg(1 - z)) < pi + + c14 = And(Eq(phi, 0), bstar - 1 + cstar <= 0, + Or(And(Ne(zos, 1), _cond(zos)), + And(re(mu + rho + v - u) < 1, Eq(zos, 1)))) + + c14_alt = And(Eq(phi, 0), cstar - 1 + bstar <= 0, + Or(And(Ne(zso, 1), _cond(zso)), + And(re(mu + rho + q - p) < 1, Eq(zso, 1)))) + + # Since r=k=l=1, in our case there is c14_alt which is the same as calling + # us with (g1, g2) = (g2, g1). The conditions below enumerate all cases + # (i.e. we don't have to try arguments reversed by hand), and indeed try + # all symmetric cases. (i.e. whenever there is a condition involving c14, + # there is also a dual condition which is exactly what we would get when g1, + # g2 were interchanged, *but c14 was unaltered*). + # Hence the following seems correct: + c14 = Or(c14, c14_alt) + + ''' + When `c15` is NaN (e.g. from `psi` being NaN as happens during + 'test_issue_4992' and/or `theta` is NaN as in 'test_issue_6253', + both in `test_integrals.py`) the comparison to 0 formerly gave False + whereas now an error is raised. To keep the old behavior, the value + of NaN is replaced with False but perhaps a closer look at this condition + should be made: XXX how should conditions leading to c15=NaN be handled? + ''' + try: + lambda_c = (q - p)*Abs(omega)**(1/(q - p))*cos(psi) \ + + (v - u)*Abs(sigma)**(1/(v - u))*cos(theta) + # the TypeError might be raised here, e.g. if lambda_c is NaN + if _eval_cond(lambda_c > 0) != False: + c15 = (lambda_c > 0) + else: + def lambda_s0(c1, c2): + return c1*(q - p)*Abs(omega)**(1/(q - p))*sin(psi) \ + + c2*(v - u)*Abs(sigma)**(1/(v - u))*sin(theta) + lambda_s = Piecewise( + ((lambda_s0(+1, +1)*lambda_s0(-1, -1)), + And(Eq(unbranched_argument(sigma), 0), Eq(unbranched_argument(omega), 0))), + (lambda_s0(sign(unbranched_argument(omega)), +1)*lambda_s0(sign(unbranched_argument(omega)), -1), + And(Eq(unbranched_argument(sigma), 0), Ne(unbranched_argument(omega), 0))), + (lambda_s0(+1, sign(unbranched_argument(sigma)))*lambda_s0(-1, sign(unbranched_argument(sigma))), + And(Ne(unbranched_argument(sigma), 0), Eq(unbranched_argument(omega), 0))), + (lambda_s0(sign(unbranched_argument(omega)), sign(unbranched_argument(sigma))), True)) + tmp = [lambda_c > 0, + And(Eq(lambda_c, 0), Ne(lambda_s, 0), re(eta) > -1), + And(Eq(lambda_c, 0), Eq(lambda_s, 0), re(eta) > 0)] + c15 = Or(*tmp) + except TypeError: + c15 = False + for cond, i in [(c1, 1), (c2, 2), (c3, 3), (c4, 4), (c5, 5), (c6, 6), + (c7, 7), (c8, 8), (c9, 9), (c10, 10), (c11, 11), + (c12, 12), (c13, 13), (c14, 14), (c15, 15)]: + _debugf(' c%s: %s', (i, cond)) + + # We will return Or(*conds) + conds = [] + + def pr(count): + _debugf(' case %s: %s', (count, conds[-1])) + conds += [And(m*n*s*t != 0, bstar.is_positive is True, cstar.is_positive is True, c1, c2, c3, c10, + c12)] # 1 + pr(1) + conds += [And(Eq(u, v), Eq(bstar, 0), cstar.is_positive is True, sigma.is_positive is True, re(rho) < 1, + c1, c2, c3, c12)] # 2 + pr(2) + conds += [And(Eq(p, q), Eq(cstar, 0), bstar.is_positive is True, omega.is_positive is True, re(mu) < 1, + c1, c2, c3, c10)] # 3 + pr(3) + conds += [And(Eq(p, q), Eq(u, v), Eq(bstar, 0), Eq(cstar, 0), + sigma.is_positive is True, omega.is_positive is True, re(mu) < 1, re(rho) < 1, + Ne(sigma, omega), c1, c2, c3)] # 4 + pr(4) + conds += [And(Eq(p, q), Eq(u, v), Eq(bstar, 0), Eq(cstar, 0), + sigma.is_positive is True, omega.is_positive is True, re(mu + rho) < 1, + Ne(omega, sigma), c1, c2, c3)] # 5 + pr(5) + conds += [And(p > q, s.is_positive is True, bstar.is_positive is True, cstar >= 0, + c1, c2, c3, c5, c10, c13)] # 6 + pr(6) + conds += [And(p < q, t.is_positive is True, bstar.is_positive is True, cstar >= 0, + c1, c2, c3, c4, c10, c13)] # 7 + pr(7) + conds += [And(u > v, m.is_positive is True, cstar.is_positive is True, bstar >= 0, + c1, c2, c3, c7, c11, c12)] # 8 + pr(8) + conds += [And(u < v, n.is_positive is True, cstar.is_positive is True, bstar >= 0, + c1, c2, c3, c6, c11, c12)] # 9 + pr(9) + conds += [And(p > q, Eq(u, v), Eq(bstar, 0), cstar >= 0, sigma.is_positive is True, + re(rho) < 1, c1, c2, c3, c5, c13)] # 10 + pr(10) + conds += [And(p < q, Eq(u, v), Eq(bstar, 0), cstar >= 0, sigma.is_positive is True, + re(rho) < 1, c1, c2, c3, c4, c13)] # 11 + pr(11) + conds += [And(Eq(p, q), u > v, bstar >= 0, Eq(cstar, 0), omega.is_positive is True, + re(mu) < 1, c1, c2, c3, c7, c11)] # 12 + pr(12) + conds += [And(Eq(p, q), u < v, bstar >= 0, Eq(cstar, 0), omega.is_positive is True, + re(mu) < 1, c1, c2, c3, c6, c11)] # 13 + pr(13) + conds += [And(p < q, u > v, bstar >= 0, cstar >= 0, + c1, c2, c3, c4, c7, c11, c13)] # 14 + pr(14) + conds += [And(p > q, u < v, bstar >= 0, cstar >= 0, + c1, c2, c3, c5, c6, c11, c13)] # 15 + pr(15) + conds += [And(p > q, u > v, bstar >= 0, cstar >= 0, + c1, c2, c3, c5, c7, c8, c11, c13, c14)] # 16 + pr(16) + conds += [And(p < q, u < v, bstar >= 0, cstar >= 0, + c1, c2, c3, c4, c6, c9, c11, c13, c14)] # 17 + pr(17) + conds += [And(Eq(t, 0), s.is_positive is True, bstar.is_positive is True, phi.is_positive is True, c1, c2, c10)] # 18 + pr(18) + conds += [And(Eq(s, 0), t.is_positive is True, bstar.is_positive is True, phi.is_negative is True, c1, c3, c10)] # 19 + pr(19) + conds += [And(Eq(n, 0), m.is_positive is True, cstar.is_positive is True, phi.is_negative is True, c1, c2, c12)] # 20 + pr(20) + conds += [And(Eq(m, 0), n.is_positive is True, cstar.is_positive is True, phi.is_positive is True, c1, c3, c12)] # 21 + pr(21) + conds += [And(Eq(s*t, 0), bstar.is_positive is True, cstar.is_positive is True, + c1, c2, c3, c10, c12)] # 22 + pr(22) + conds += [And(Eq(m*n, 0), bstar.is_positive is True, cstar.is_positive is True, + c1, c2, c3, c10, c12)] # 23 + pr(23) + + # The following case is from [Luke1969]. As far as I can tell, it is *not* + # covered by Prudnikov's. + # Let G1 and G2 be the two G-functions. Suppose the integral exists from + # 0 to a > 0 (this is easy the easy part), that G1 is exponential decay at + # infinity, and that the mellin transform of G2 exists. + # Then the integral exists. + mt1_exists = _check_antecedents_1(g1, x, helper=True) + mt2_exists = _check_antecedents_1(g2, x, helper=True) + conds += [And(mt2_exists, Eq(t, 0), u < s, bstar.is_positive is True, c10, c1, c2, c3)] + pr('E1') + conds += [And(mt2_exists, Eq(s, 0), v < t, bstar.is_positive is True, c10, c1, c2, c3)] + pr('E2') + conds += [And(mt1_exists, Eq(n, 0), p < m, cstar.is_positive is True, c12, c1, c2, c3)] + pr('E3') + conds += [And(mt1_exists, Eq(m, 0), q < n, cstar.is_positive is True, c12, c1, c2, c3)] + pr('E4') + + # Let's short-circuit if this worked ... + # the rest is corner-cases and terrible to read. + r = Or(*conds) + if _eval_cond(r) != False: + return r + + conds += [And(m + n > p, Eq(t, 0), Eq(phi, 0), s.is_positive is True, bstar.is_positive is True, cstar.is_negative is True, + Abs(unbranched_argument(omega)) < (m + n - p + 1)*pi, + c1, c2, c10, c14, c15)] # 24 + pr(24) + conds += [And(m + n > q, Eq(s, 0), Eq(phi, 0), t.is_positive is True, bstar.is_positive is True, cstar.is_negative is True, + Abs(unbranched_argument(omega)) < (m + n - q + 1)*pi, + c1, c3, c10, c14, c15)] # 25 + pr(25) + conds += [And(Eq(p, q - 1), Eq(t, 0), Eq(phi, 0), s.is_positive is True, bstar.is_positive is True, + cstar >= 0, cstar*pi < Abs(unbranched_argument(omega)), + c1, c2, c10, c14, c15)] # 26 + pr(26) + conds += [And(Eq(p, q + 1), Eq(s, 0), Eq(phi, 0), t.is_positive is True, bstar.is_positive is True, + cstar >= 0, cstar*pi < Abs(unbranched_argument(omega)), + c1, c3, c10, c14, c15)] # 27 + pr(27) + conds += [And(p < q - 1, Eq(t, 0), Eq(phi, 0), s.is_positive is True, bstar.is_positive is True, + cstar >= 0, cstar*pi < Abs(unbranched_argument(omega)), + Abs(unbranched_argument(omega)) < (m + n - p + 1)*pi, + c1, c2, c10, c14, c15)] # 28 + pr(28) + conds += [And( + p > q + 1, Eq(s, 0), Eq(phi, 0), t.is_positive is True, bstar.is_positive is True, cstar >= 0, + cstar*pi < Abs(unbranched_argument(omega)), + Abs(unbranched_argument(omega)) < (m + n - q + 1)*pi, + c1, c3, c10, c14, c15)] # 29 + pr(29) + conds += [And(Eq(n, 0), Eq(phi, 0), s + t > 0, m.is_positive is True, cstar.is_positive is True, bstar.is_negative is True, + Abs(unbranched_argument(sigma)) < (s + t - u + 1)*pi, + c1, c2, c12, c14, c15)] # 30 + pr(30) + conds += [And(Eq(m, 0), Eq(phi, 0), s + t > v, n.is_positive is True, cstar.is_positive is True, bstar.is_negative is True, + Abs(unbranched_argument(sigma)) < (s + t - v + 1)*pi, + c1, c3, c12, c14, c15)] # 31 + pr(31) + conds += [And(Eq(n, 0), Eq(phi, 0), Eq(u, v - 1), m.is_positive is True, cstar.is_positive is True, + bstar >= 0, bstar*pi < Abs(unbranched_argument(sigma)), + Abs(unbranched_argument(sigma)) < (bstar + 1)*pi, + c1, c2, c12, c14, c15)] # 32 + pr(32) + conds += [And(Eq(m, 0), Eq(phi, 0), Eq(u, v + 1), n.is_positive is True, cstar.is_positive is True, + bstar >= 0, bstar*pi < Abs(unbranched_argument(sigma)), + Abs(unbranched_argument(sigma)) < (bstar + 1)*pi, + c1, c3, c12, c14, c15)] # 33 + pr(33) + conds += [And( + Eq(n, 0), Eq(phi, 0), u < v - 1, m.is_positive is True, cstar.is_positive is True, bstar >= 0, + bstar*pi < Abs(unbranched_argument(sigma)), + Abs(unbranched_argument(sigma)) < (s + t - u + 1)*pi, + c1, c2, c12, c14, c15)] # 34 + pr(34) + conds += [And( + Eq(m, 0), Eq(phi, 0), u > v + 1, n.is_positive is True, cstar.is_positive is True, bstar >= 0, + bstar*pi < Abs(unbranched_argument(sigma)), + Abs(unbranched_argument(sigma)) < (s + t - v + 1)*pi, + c1, c3, c12, c14, c15)] # 35 + pr(35) + + return Or(*conds) + + # NOTE An alternative, but as far as I can tell weaker, set of conditions + # can be found in [L, section 5.6.2]. + + +def _int0oo(g1, g2, x): + """ + Express integral from zero to infinity g1*g2 using a G function, + assuming the necessary conditions are fulfilled. + + Examples + ======== + + >>> from sympy.integrals.meijerint import _int0oo + >>> from sympy.abc import s, t, m + >>> from sympy import meijerg, S + >>> g1 = meijerg([], [], [-S(1)/2, 0], [], s**2*t/4) + >>> g2 = meijerg([], [], [m/2], [-m/2], t/4) + >>> _int0oo(g1, g2, t) + 4*meijerg(((0, 1/2), ()), ((m/2,), (-m/2,)), s**(-2))/s**2 + """ + # See: [L, section 5.6.2, equation (1)] + eta, _ = _get_coeff_exp(g1.argument, x) + omega, _ = _get_coeff_exp(g2.argument, x) + + def neg(l): + return [-x for x in l] + a1 = neg(g1.bm) + list(g2.an) + a2 = list(g2.aother) + neg(g1.bother) + b1 = neg(g1.an) + list(g2.bm) + b2 = list(g2.bother) + neg(g1.aother) + return meijerg(a1, a2, b1, b2, omega/eta)/eta + + +def _rewrite_inversion(fac, po, g, x): + """ Absorb ``po`` == x**s into g. """ + _, s = _get_coeff_exp(po, x) + a, b = _get_coeff_exp(g.argument, x) + + def tr(l): + return [t + s/b for t in l] + from sympy.simplify import powdenest + return (powdenest(fac/a**(s/b), polar=True), + meijerg(tr(g.an), tr(g.aother), tr(g.bm), tr(g.bother), g.argument)) + + +def _check_antecedents_inversion(g, x): + """ Check antecedents for the laplace inversion integral. """ + _debug('Checking antecedents for inversion:') + z = g.argument + _, e = _get_coeff_exp(z, x) + if e < 0: + _debug(' Flipping G.') + # We want to assume that argument gets large as |x| -> oo + return _check_antecedents_inversion(_flip_g(g), x) + + def statement_half(a, b, c, z, plus): + coeff, exponent = _get_coeff_exp(z, x) + a *= exponent + b *= coeff**c + c *= exponent + conds = [] + wp = b*exp(S.ImaginaryUnit*re(c)*pi/2) + wm = b*exp(-S.ImaginaryUnit*re(c)*pi/2) + if plus: + w = wp + else: + w = wm + conds += [And(Or(Eq(b, 0), re(c) <= 0), re(a) <= -1)] + conds += [And(Ne(b, 0), Eq(im(c), 0), re(c) > 0, re(w) < 0)] + conds += [And(Ne(b, 0), Eq(im(c), 0), re(c) > 0, re(w) <= 0, + re(a) <= -1)] + return Or(*conds) + + def statement(a, b, c, z): + """ Provide a convergence statement for z**a * exp(b*z**c), + c/f sphinx docs. """ + return And(statement_half(a, b, c, z, True), + statement_half(a, b, c, z, False)) + + # Notations from [L], section 5.7-10 + m, n, p, q = S([len(g.bm), len(g.an), len(g.ap), len(g.bq)]) + tau = m + n - p + nu = q - m - n + rho = (tau - nu)/2 + sigma = q - p + if sigma == 1: + epsilon = S.Half + elif sigma > 1: + epsilon = 1 + else: + epsilon = S.NaN + theta = ((1 - sigma)/2 + Add(*g.bq) - Add(*g.ap))/sigma + delta = g.delta + _debugf(' m=%s, n=%s, p=%s, q=%s, tau=%s, nu=%s, rho=%s, sigma=%s', + (m, n, p, q, tau, nu, rho, sigma)) + _debugf(' epsilon=%s, theta=%s, delta=%s', (epsilon, theta, delta)) + + # First check if the computation is valid. + if not (g.delta >= e/2 or (p >= 1 and p >= q)): + _debug(' Computation not valid for these parameters.') + return False + + # Now check if the inversion integral exists. + + # Test "condition A" + for a, b in itertools.product(g.an, g.bm): + if (a - b).is_integer and a > b: + _debug(' Not a valid G function.') + return False + + # There are two cases. If p >= q, we can directly use a slater expansion + # like [L], 5.2 (11). Note in particular that the asymptotics of such an + # expansion even hold when some of the parameters differ by integers, i.e. + # the formula itself would not be valid! (b/c G functions are cts. in their + # parameters) + # When p < q, we need to use the theorems of [L], 5.10. + + if p >= q: + _debug(' Using asymptotic Slater expansion.') + return And(*[statement(a - 1, 0, 0, z) for a in g.an]) + + def E(z): + return And(*[statement(a - 1, 0, 0, z) for a in g.an]) + + def H(z): + return statement(theta, -sigma, 1/sigma, z) + + def Hp(z): + return statement_half(theta, -sigma, 1/sigma, z, True) + + def Hm(z): + return statement_half(theta, -sigma, 1/sigma, z, False) + + # [L], section 5.10 + conds = [] + # Theorem 1 -- p < q from test above + conds += [And(1 <= n, 1 <= m, rho*pi - delta >= pi/2, delta > 0, + E(z*exp(S.ImaginaryUnit*pi*(nu + 1))))] + # Theorem 2, statements (2) and (3) + conds += [And(p + 1 <= m, m + 1 <= q, delta > 0, delta < pi/2, n == 0, + (m - p + 1)*pi - delta >= pi/2, + Hp(z*exp(S.ImaginaryUnit*pi*(q - m))), + Hm(z*exp(-S.ImaginaryUnit*pi*(q - m))))] + # Theorem 2, statement (5) -- p < q from test above + conds += [And(m == q, n == 0, delta > 0, + (sigma + epsilon)*pi - delta >= pi/2, H(z))] + # Theorem 3, statements (6) and (7) + conds += [And(Or(And(p <= q - 2, 1 <= tau, tau <= sigma/2), + And(p + 1 <= m + n, m + n <= (p + q)/2)), + delta > 0, delta < pi/2, (tau + 1)*pi - delta >= pi/2, + Hp(z*exp(S.ImaginaryUnit*pi*nu)), + Hm(z*exp(-S.ImaginaryUnit*pi*nu)))] + # Theorem 4, statements (10) and (11) -- p < q from test above + conds += [And(1 <= m, rho > 0, delta > 0, delta + rho*pi < pi/2, + (tau + epsilon)*pi - delta >= pi/2, + Hp(z*exp(S.ImaginaryUnit*pi*nu)), + Hm(z*exp(-S.ImaginaryUnit*pi*nu)))] + # Trivial case + conds += [m == 0] + + # TODO + # Theorem 5 is quite general + # Theorem 6 contains special cases for q=p+1 + + return Or(*conds) + + +def _int_inversion(g, x, t): + """ + Compute the laplace inversion integral, assuming the formula applies. + """ + b, a = _get_coeff_exp(g.argument, x) + C, g = _inflate_fox_h(meijerg(g.an, g.aother, g.bm, g.bother, b/t**a), -a) + return C/t*g + + +#################################################################### +# Finally, the real meat. +#################################################################### + +_lookup_table = None + + +@cacheit +@timeit +def _rewrite_single(f, x, recursive=True): + """ + Try to rewrite f as a sum of single G functions of the form + C*x**s*G(a*x**b), where b is a rational number and C is independent of x. + We guarantee that result.argument.as_coeff_mul(x) returns (a, (x**b,)) + or (a, ()). + Returns a list of tuples (C, s, G) and a condition cond. + Returns None on failure. + """ + from .transforms import (mellin_transform, inverse_mellin_transform, + IntegralTransformError, MellinTransformStripError) + + global _lookup_table + if not _lookup_table: + _lookup_table = {} + _create_lookup_table(_lookup_table) + + if isinstance(f, meijerg): + coeff, m = factor(f.argument, x).as_coeff_mul(x) + if len(m) > 1: + return None + m = m[0] + if m.is_Pow: + if m.base != x or not m.exp.is_Rational: + return None + elif m != x: + return None + return [(1, 0, meijerg(f.an, f.aother, f.bm, f.bother, coeff*m))], True + + f_ = f + f = f.subs(x, z) + t = _mytype(f, z) + if t in _lookup_table: + l = _lookup_table[t] + for formula, terms, cond, hint in l: + subs = f.match(formula, old=True) + if subs: + subs_ = {} + for fro, to in subs.items(): + subs_[fro] = unpolarify(polarify(to, lift=True), + exponents_only=True) + subs = subs_ + if not isinstance(hint, bool): + hint = hint.subs(subs) + if hint == False: + continue + if not isinstance(cond, (bool, BooleanAtom)): + cond = unpolarify(cond.subs(subs)) + if _eval_cond(cond) == False: + continue + if not isinstance(terms, list): + terms = terms(subs) + res = [] + for fac, g in terms: + r1 = _get_coeff_exp(unpolarify(fac.subs(subs).subs(z, x), + exponents_only=True), x) + try: + g = g.subs(subs).subs(z, x) + except ValueError: + continue + # NOTE these substitutions can in principle introduce oo, + # zoo and other absurdities. It shouldn't matter, + # but better be safe. + if Tuple(*(r1 + (g,))).has(S.Infinity, S.ComplexInfinity, S.NegativeInfinity): + continue + g = meijerg(g.an, g.aother, g.bm, g.bother, + unpolarify(g.argument, exponents_only=True)) + res.append(r1 + (g,)) + if res: + return res, cond + + # try recursive mellin transform + if not recursive: + return None + _debug('Trying recursive Mellin transform method.') + + def my_imt(F, s, x, strip): + """ Calling simplify() all the time is slow and not helpful, since + most of the time it only factors things in a way that has to be + un-done anyway. But sometimes it can remove apparent poles. """ + # XXX should this be in inverse_mellin_transform? + try: + return inverse_mellin_transform(F, s, x, strip, + as_meijerg=True, needeval=True) + except MellinTransformStripError: + from sympy.simplify import simplify + return inverse_mellin_transform( + simplify(cancel(expand(F))), s, x, strip, + as_meijerg=True, needeval=True) + f = f_ + s = _dummy('s', 'rewrite-single', f) + # to avoid infinite recursion, we have to force the two g functions case + + def my_integrator(f, x): + r = _meijerint_definite_4(f, x, only_double=True) + if r is not None: + from sympy.simplify import hyperexpand + res, cond = r + res = _my_unpolarify(hyperexpand(res, rewrite='nonrepsmall')) + return Piecewise((res, cond), + (Integral(f, (x, S.Zero, S.Infinity)), True)) + return Integral(f, (x, S.Zero, S.Infinity)) + try: + F, strip, _ = mellin_transform(f, x, s, integrator=my_integrator, + simplify=False, needeval=True) + g = my_imt(F, s, x, strip) + except IntegralTransformError: + g = None + if g is None: + # We try to find an expression by analytic continuation. + # (also if the dummy is already in the expression, there is no point in + # putting in another one) + a = _dummy_('a', 'rewrite-single') + if a not in f.free_symbols and _is_analytic(f, x): + try: + F, strip, _ = mellin_transform(f.subs(x, a*x), x, s, + integrator=my_integrator, + needeval=True, simplify=False) + g = my_imt(F, s, x, strip).subs(a, 1) + except IntegralTransformError: + g = None + if g is None or g.has(S.Infinity, S.NaN, S.ComplexInfinity): + _debug('Recursive Mellin transform failed.') + return None + args = Add.make_args(g) + res = [] + for f in args: + c, m = f.as_coeff_mul(x) + if len(m) > 1: + raise NotImplementedError('Unexpected form...') + g = m[0] + a, b = _get_coeff_exp(g.argument, x) + res += [(c, 0, meijerg(g.an, g.aother, g.bm, g.bother, + unpolarify(polarify( + a, lift=True), exponents_only=True) + *x**b))] + _debug('Recursive Mellin transform worked:', g) + return res, True + + +def _rewrite1(f, x, recursive=True): + """ + Try to rewrite ``f`` using a (sum of) single G functions with argument a*x**b. + Return fac, po, g such that f = fac*po*g, fac is independent of ``x``. + and po = x**s. + Here g is a result from _rewrite_single. + Return None on failure. + """ + fac, po, g = _split_mul(f, x) + g = _rewrite_single(g, x, recursive) + if g: + return fac, po, g[0], g[1] + + +def _rewrite2(f, x): + """ + Try to rewrite ``f`` as a product of two G functions of arguments a*x**b. + Return fac, po, g1, g2 such that f = fac*po*g1*g2, where fac is + independent of x and po is x**s. + Here g1 and g2 are results of _rewrite_single. + Returns None on failure. + """ + fac, po, g = _split_mul(f, x) + if any(_rewrite_single(expr, x, False) is None for expr in _mul_args(g)): + return None + l = _mul_as_two_parts(g) + if not l: + return None + l = list(ordered(l, [ + lambda p: max(len(_exponents(p[0], x)), len(_exponents(p[1], x))), + lambda p: max(len(_functions(p[0], x)), len(_functions(p[1], x))), + lambda p: max(len(_find_splitting_points(p[0], x)), + len(_find_splitting_points(p[1], x)))])) + + for recursive, (fac1, fac2) in itertools.product((False, True), l): + g1 = _rewrite_single(fac1, x, recursive) + g2 = _rewrite_single(fac2, x, recursive) + if g1 and g2: + cond = And(g1[1], g2[1]) + if cond != False: + return fac, po, g1[0], g2[0], cond + + +def meijerint_indefinite(f, x): + """ + Compute an indefinite integral of ``f`` by rewriting it as a G function. + + Examples + ======== + + >>> from sympy.integrals.meijerint import meijerint_indefinite + >>> from sympy import sin + >>> from sympy.abc import x + >>> meijerint_indefinite(sin(x), x) + -cos(x) + """ + f = sympify(f) + results = [] + for a in sorted(_find_splitting_points(f, x) | {S.Zero}, key=default_sort_key): + res = _meijerint_indefinite_1(f.subs(x, x + a), x) + if not res: + continue + res = res.subs(x, x - a) + if _has(res, hyper, meijerg): + results.append(res) + else: + return res + if f.has(HyperbolicFunction): + _debug('Try rewriting hyperbolics in terms of exp.') + rv = meijerint_indefinite( + _rewrite_hyperbolics_as_exp(f), x) + if rv: + if not isinstance(rv, list): + from sympy.simplify.radsimp import collect + return collect(factor_terms(rv), rv.atoms(exp)) + results.extend(rv) + if results: + return next(ordered(results)) + + +def _meijerint_indefinite_1(f, x): + """ Helper that does not attempt any substitution. """ + _debug('Trying to compute the indefinite integral of', f, 'wrt', x) + from sympy.simplify import hyperexpand, powdenest + + gs = _rewrite1(f, x) + if gs is None: + # Note: the code that calls us will do expand() and try again + return None + + fac, po, gl, cond = gs + _debug(' could rewrite:', gs) + res = S.Zero + for C, s, g in gl: + a, b = _get_coeff_exp(g.argument, x) + _, c = _get_coeff_exp(po, x) + c += s + + # we do a substitution t=a*x**b, get integrand fac*t**rho*g + fac_ = fac * C * x**(1 + c) / b + rho = (c + 1)/b + + # we now use t**rho*G(params, t) = G(params + rho, t) + # [L, page 150, equation (4)] + # and integral G(params, t) dt = G(1, params+1, 0, t) + # (or a similar expression with 1 and 0 exchanged ... pick the one + # which yields a well-defined function) + # [R, section 5] + # (Note that this dummy will immediately go away again, so we + # can safely pass S.One for ``expr``.) + t = _dummy('t', 'meijerint-indefinite', S.One) + + def tr(p): + return [a + rho for a in p] + if any(b.is_integer and (b <= 0) == True for b in tr(g.bm)): + r = -meijerg( + list(g.an), list(g.aother) + [1-rho], list(g.bm) + [-rho], list(g.bother), t) + else: + r = meijerg( + list(g.an) + [1-rho], list(g.aother), list(g.bm), list(g.bother) + [-rho], t) + # The antiderivative is most often expected to be defined + # in the neighborhood of x = 0. + if b.is_extended_nonnegative and not f.subs(x, 0).has(S.NaN, S.ComplexInfinity): + place = 0 # Assume we can expand at zero + else: + place = None + r = hyperexpand(r.subs(t, a*x**b), place=place) + + # now substitute back + # Note: we really do want the powers of x to combine. + res += powdenest(fac_*r, polar=True) + + def _clean(res): + """This multiplies out superfluous powers of x we created, and chops off + constants: + + >> _clean(x*(exp(x)/x - 1/x) + 3) + exp(x) + + cancel is used before mul_expand since it is possible for an + expression to have an additive constant that does not become isolated + with simple expansion. Such a situation was identified in issue 6369: + + Examples + ======== + + >>> from sympy import sqrt, cancel + >>> from sympy.abc import x + >>> a = sqrt(2*x + 1) + >>> bad = (3*x*a**5 + 2*x - a**5 + 1)/a**2 + >>> bad.expand().as_independent(x)[0] + 0 + >>> cancel(bad).expand().as_independent(x)[0] + 1 + """ + res = expand_mul(cancel(res), deep=False) + return Add._from_args(res.as_coeff_add(x)[1]) + + res = piecewise_fold(res, evaluate=None) + if res.is_Piecewise: + newargs = [] + for e, c in res.args: + e = _my_unpolarify(_clean(e)) + newargs += [(e, c)] + res = Piecewise(*newargs, evaluate=False) + else: + res = _my_unpolarify(_clean(res)) + return Piecewise((res, _my_unpolarify(cond)), (Integral(f, x), True)) + + +@timeit +def meijerint_definite(f, x, a, b): + """ + Integrate ``f`` over the interval [``a``, ``b``], by rewriting it as a product + of two G functions, or as a single G function. + + Return res, cond, where cond are convergence conditions. + + Examples + ======== + + >>> from sympy.integrals.meijerint import meijerint_definite + >>> from sympy import exp, oo + >>> from sympy.abc import x + >>> meijerint_definite(exp(-x**2), x, -oo, oo) + (sqrt(pi), True) + + This function is implemented as a succession of functions + meijerint_definite, _meijerint_definite_2, _meijerint_definite_3, + _meijerint_definite_4. Each function in the list calls the next one + (presumably) several times. This means that calling meijerint_definite + can be very costly. + """ + # This consists of three steps: + # 1) Change the integration limits to 0, oo + # 2) Rewrite in terms of G functions + # 3) Evaluate the integral + # + # There are usually several ways of doing this, and we want to try all. + # This function does (1), calls _meijerint_definite_2 for step (2). + _debugf('Integrating %s wrt %s from %s to %s.', (f, x, a, b)) + f = sympify(f) + if f.has(DiracDelta): + _debug('Integrand has DiracDelta terms - giving up.') + return None + + if f.has(SingularityFunction): + _debug('Integrand has Singularity Function terms - giving up.') + return None + + f_, x_, a_, b_ = f, x, a, b + + # Let's use a dummy in case any of the boundaries has x. + d = Dummy('x') + f = f.subs(x, d) + x = d + + if a == b: + return (S.Zero, True) + + results = [] + if a is S.NegativeInfinity and b is not S.Infinity: + return meijerint_definite(f.subs(x, -x), x, -b, -a) + + elif a is S.NegativeInfinity: + # Integrating -oo to oo. We need to find a place to split the integral. + _debug(' Integrating -oo to +oo.') + innermost = _find_splitting_points(f, x) + _debug(' Sensible splitting points:', innermost) + for c in sorted(innermost, key=default_sort_key, reverse=True) + [S.Zero]: + _debug(' Trying to split at', c) + if not c.is_extended_real: + _debug(' Non-real splitting point.') + continue + res1 = _meijerint_definite_2(f.subs(x, x + c), x) + if res1 is None: + _debug(' But could not compute first integral.') + continue + res2 = _meijerint_definite_2(f.subs(x, c - x), x) + if res2 is None: + _debug(' But could not compute second integral.') + continue + res1, cond1 = res1 + res2, cond2 = res2 + cond = _condsimp(And(cond1, cond2)) + if cond == False: + _debug(' But combined condition is always false.') + continue + res = res1 + res2 + return res, cond + + elif a is S.Infinity: + res = meijerint_definite(f, x, b, S.Infinity) + return -res[0], res[1] + + elif (a, b) == (S.Zero, S.Infinity): + # This is a common case - try it directly first. + res = _meijerint_definite_2(f, x) + if res: + if _has(res[0], meijerg): + results.append(res) + else: + return res + + else: + if b is S.Infinity: + for split in _find_splitting_points(f, x): + if (a - split >= 0) == True: + _debugf('Trying x -> x + %s', split) + res = _meijerint_definite_2(f.subs(x, x + split) + *Heaviside(x + split - a), x) + if res: + if _has(res[0], meijerg): + results.append(res) + else: + return res + + f = f.subs(x, x + a) + b = b - a + a = 0 + if b is not S.Infinity: + phi = exp(S.ImaginaryUnit*arg(b)) + b = Abs(b) + f = f.subs(x, phi*x) + f *= Heaviside(b - x)*phi + b = S.Infinity + + _debug('Changed limits to', a, b) + _debug('Changed function to', f) + res = _meijerint_definite_2(f, x) + if res: + if _has(res[0], meijerg): + results.append(res) + else: + return res + if f_.has(HyperbolicFunction): + _debug('Try rewriting hyperbolics in terms of exp.') + rv = meijerint_definite( + _rewrite_hyperbolics_as_exp(f_), x_, a_, b_) + if rv: + if not isinstance(rv, list): + from sympy.simplify.radsimp import collect + rv = (collect(factor_terms(rv[0]), rv[0].atoms(exp)),) + rv[1:] + return rv + results.extend(rv) + if results: + return next(ordered(results)) + + +def _guess_expansion(f, x): + """ Try to guess sensible rewritings for integrand f(x). """ + res = [(f, 'original integrand')] + + orig = res[-1][0] + saw = {orig} + expanded = expand_mul(orig) + if expanded not in saw: + res += [(expanded, 'expand_mul')] + saw.add(expanded) + + expanded = expand(orig) + if expanded not in saw: + res += [(expanded, 'expand')] + saw.add(expanded) + + if orig.has(TrigonometricFunction, HyperbolicFunction): + expanded = expand_mul(expand_trig(orig)) + if expanded not in saw: + res += [(expanded, 'expand_trig, expand_mul')] + saw.add(expanded) + + if orig.has(cos, sin): + from sympy.simplify.fu import sincos_to_sum + reduced = sincos_to_sum(orig) + if reduced not in saw: + res += [(reduced, 'trig power reduction')] + saw.add(reduced) + + return res + + +def _meijerint_definite_2(f, x): + """ + Try to integrate f dx from zero to infinity. + + The body of this function computes various 'simplifications' + f1, f2, ... of f (e.g. by calling expand_mul(), trigexpand() + - see _guess_expansion) and calls _meijerint_definite_3 with each of + these in succession. + If _meijerint_definite_3 succeeds with any of the simplified functions, + returns this result. + """ + # This function does preparation for (2), calls + # _meijerint_definite_3 for (2) and (3) combined. + + # use a positive dummy - we integrate from 0 to oo + # XXX if a nonnegative symbol is used there will be test failures + dummy = _dummy('x', 'meijerint-definite2', f, positive=True) + f = f.subs(x, dummy) + x = dummy + + if f == 0: + return S.Zero, True + + for g, explanation in _guess_expansion(f, x): + _debug('Trying', explanation) + res = _meijerint_definite_3(g, x) + if res: + return res + + +def _meijerint_definite_3(f, x): + """ + Try to integrate f dx from zero to infinity. + + This function calls _meijerint_definite_4 to try to compute the + integral. If this fails, it tries using linearity. + """ + res = _meijerint_definite_4(f, x) + if res and res[1] != False: + return res + if f.is_Add: + _debug('Expanding and evaluating all terms.') + ress = [_meijerint_definite_4(g, x) for g in f.args] + if all(r is not None for r in ress): + conds = [] + res = S.Zero + for r, c in ress: + res += r + conds += [c] + c = And(*conds) + if c != False: + return res, c + + +def _my_unpolarify(f): + return _eval_cond(unpolarify(f)) + + +@timeit +def _meijerint_definite_4(f, x, only_double=False): + """ + Try to integrate f dx from zero to infinity. + + Explanation + =========== + + This function tries to apply the integration theorems found in literature, + i.e. it tries to rewrite f as either one or a product of two G-functions. + + The parameter ``only_double`` is used internally in the recursive algorithm + to disable trying to rewrite f as a single G-function. + """ + from sympy.simplify import hyperexpand + # This function does (2) and (3) + _debug('Integrating', f) + # Try single G function. + if not only_double: + gs = _rewrite1(f, x, recursive=False) + if gs is not None: + fac, po, g, cond = gs + _debug('Could rewrite as single G function:', fac, po, g) + res = S.Zero + for C, s, f in g: + if C == 0: + continue + C, f = _rewrite_saxena_1(fac*C, po*x**s, f, x) + res += C*_int0oo_1(f, x) + cond = And(cond, _check_antecedents_1(f, x)) + if cond == False: + break + cond = _my_unpolarify(cond) + if cond == False: + _debug('But cond is always False.') + else: + _debug('Result before branch substitutions is:', res) + return _my_unpolarify(hyperexpand(res)), cond + + # Try two G functions. + gs = _rewrite2(f, x) + if gs is not None: + for full_pb in [False, True]: + fac, po, g1, g2, cond = gs + _debug('Could rewrite as two G functions:', fac, po, g1, g2) + res = S.Zero + for C1, s1, f1 in g1: + for C2, s2, f2 in g2: + r = _rewrite_saxena(fac*C1*C2, po*x**(s1 + s2), + f1, f2, x, full_pb) + if r is None: + _debug('Non-rational exponents.') + return + C, f1_, f2_ = r + _debug('Saxena subst for yielded:', C, f1_, f2_) + cond = And(cond, _check_antecedents(f1_, f2_, x)) + if cond == False: + break + res += C*_int0oo(f1_, f2_, x) + else: + continue + break + cond = _my_unpolarify(cond) + if cond == False: + _debugf('But cond is always False (full_pb=%s).', full_pb) + else: + _debugf('Result before branch substitutions is: %s', (res, )) + if only_double: + return res, cond + return _my_unpolarify(hyperexpand(res)), cond + + +def meijerint_inversion(f, x, t): + r""" + Compute the inverse laplace transform + $\int_{c+i\infty}^{c-i\infty} f(x) e^{tx}\, dx$, + for real c larger than the real part of all singularities of ``f``. + + Note that ``t`` is always assumed real and positive. + + Return None if the integral does not exist or could not be evaluated. + + Examples + ======== + + >>> from sympy.abc import x, t + >>> from sympy.integrals.meijerint import meijerint_inversion + >>> meijerint_inversion(1/x, x, t) + Heaviside(t) + """ + f_ = f + t_ = t + t = Dummy('t', polar=True) # We don't want sqrt(t**2) = abs(t) etc + f = f.subs(t_, t) + _debug('Laplace-inverting', f) + if not _is_analytic(f, x): + _debug('But expression is not analytic.') + return None + # Exponentials correspond to shifts; we filter them out and then + # shift the result later. If we are given an Add this will not + # work, but the calling code will take care of that. + shift = S.Zero + + if f.is_Mul: + args = list(f.args) + elif isinstance(f, exp): + args = [f] + else: + args = None + + if args: + newargs = [] + exponentials = [] + while args: + arg = args.pop() + if isinstance(arg, exp): + arg2 = expand(arg) + if arg2.is_Mul: + args += arg2.args + continue + try: + a, b = _get_coeff_exp(arg.args[0], x) + except _CoeffExpValueError: + b = 0 + if b == 1: + exponentials.append(a) + else: + newargs.append(arg) + elif arg.is_Pow: + arg2 = expand(arg) + if arg2.is_Mul: + args += arg2.args + continue + if x not in arg.base.free_symbols: + try: + a, b = _get_coeff_exp(arg.exp, x) + except _CoeffExpValueError: + b = 0 + if b == 1: + exponentials.append(a*log(arg.base)) + newargs.append(arg) + else: + newargs.append(arg) + shift = Add(*exponentials) + f = Mul(*newargs) + + if x not in f.free_symbols: + _debug('Expression consists of constant and exp shift:', f, shift) + cond = Eq(im(shift), 0) + if cond == False: + _debug('but shift is nonreal, cannot be a Laplace transform') + return None + res = f*DiracDelta(t + shift) + _debug('Result is a delta function, possibly conditional:', res, cond) + # cond is True or Eq + return Piecewise((res.subs(t, t_), cond)) + + gs = _rewrite1(f, x) + if gs is not None: + fac, po, g, cond = gs + _debug('Could rewrite as single G function:', fac, po, g) + res = S.Zero + for C, s, f in g: + C, f = _rewrite_inversion(fac*C, po*x**s, f, x) + res += C*_int_inversion(f, x, t) + cond = And(cond, _check_antecedents_inversion(f, x)) + if cond == False: + break + cond = _my_unpolarify(cond) + if cond == False: + _debug('But cond is always False.') + else: + _debug('Result before branch substitution:', res) + from sympy.simplify import hyperexpand + res = _my_unpolarify(hyperexpand(res)) + if not res.has(Heaviside): + res *= Heaviside(t) + res = res.subs(t, t + shift) + if not isinstance(cond, bool): + cond = cond.subs(t, t + shift) + from .transforms import InverseLaplaceTransform + return Piecewise((res.subs(t, t_), cond), + (InverseLaplaceTransform(f_.subs(t, t_), x, t_, None), True)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/meijerint_doc.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/meijerint_doc.py new file mode 100644 index 0000000000000000000000000000000000000000..1df385db6b6fe6d46d4a14217aa53d1fdd9670b5 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/meijerint_doc.py @@ -0,0 +1,38 @@ +""" This module cooks up a docstring when imported. Its only purpose is to + be displayed in the sphinx documentation. """ + +from __future__ import annotations +from typing import Any + +from sympy.integrals.meijerint import _create_lookup_table +from sympy.core.add import Add +from sympy.core.basic import Basic +from sympy.core.expr import Expr +from sympy.core.relational import Eq +from sympy.core.symbol import Symbol +from sympy.printing.latex import latex + +t: dict[tuple[type[Basic], ...], list[Any]] = {} +_create_lookup_table(t) + + +doc = "" +for about, category in t.items(): + if about == (): + doc += 'Elementary functions:\n\n' + else: + doc += 'Functions involving ' + ', '.join('`%s`' % latex( + list(category[0][0].atoms(func))[0]) for func in about) + ':\n\n' + for formula, gs, cond, hint in category: + if not isinstance(gs, list): + g: Expr = Symbol('\\text{generated}') + else: + g = Add(*[fac*f for (fac, f) in gs]) + obj = Eq(formula, g) + if cond is True: + cond = "" + else: + cond = ',\\text{ if } %s' % latex(cond) + doc += ".. math::\n %s%s\n\n" % (latex(obj), cond) + +__doc__ = doc diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/prde.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/prde.py new file mode 100644 index 0000000000000000000000000000000000000000..28e91ea0ff3a82cbeca24c6ed4267503ceb758b5 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/prde.py @@ -0,0 +1,1333 @@ +""" +Algorithms for solving Parametric Risch Differential Equations. + +The methods used for solving Parametric Risch Differential Equations parallel +those for solving Risch Differential Equations. See the outline in the +docstring of rde.py for more information. + +The Parametric Risch Differential Equation problem is, given f, g1, ..., gm in +K(t), to determine if there exist y in K(t) and c1, ..., cm in Const(K) such +that Dy + f*y == Sum(ci*gi, (i, 1, m)), and to find such y and ci if they exist. + +For the algorithms here G is a list of tuples of factions of the terms on the +right hand side of the equation (i.e., gi in k(t)), and Q is a list of terms on +the right hand side of the equation (i.e., qi in k[t]). See the docstring of +each function for more information. +""" +import itertools +from functools import reduce + +from sympy.core.intfunc import ilcm +from sympy.core import Dummy, Add, Mul, Pow, S +from sympy.integrals.rde import (order_at, order_at_oo, weak_normalizer, + bound_degree) +from sympy.integrals.risch import (gcdex_diophantine, frac_in, derivation, + residue_reduce, splitfactor, residue_reduce_derivation, DecrementLevel, + recognize_log_derivative) +from sympy.polys import Poly, lcm, cancel, sqf_list +from sympy.polys.polymatrix import PolyMatrix as Matrix +from sympy.solvers import solve + +zeros = Matrix.zeros +eye = Matrix.eye + + +def prde_normal_denom(fa, fd, G, DE): + """ + Parametric Risch Differential Equation - Normal part of the denominator. + + Explanation + =========== + + Given a derivation D on k[t] and f, g1, ..., gm in k(t) with f weakly + normalized with respect to t, return the tuple (a, b, G, h) such that + a, h in k[t], b in k, G = [g1, ..., gm] in k(t)^m, and for any solution + c1, ..., cm in Const(k) and y in k(t) of Dy + f*y == Sum(ci*gi, (i, 1, m)), + q == y*h in k satisfies a*Dq + b*q == Sum(ci*Gi, (i, 1, m)). + """ + dn, ds = splitfactor(fd, DE) + Gas, Gds = list(zip(*G)) + gd = reduce(lambda i, j: i.lcm(j), Gds, Poly(1, DE.t)) + en, es = splitfactor(gd, DE) + + p = dn.gcd(en) + h = en.gcd(en.diff(DE.t)).quo(p.gcd(p.diff(DE.t))) + + a = dn*h + c = a*h + + ba = a*fa - dn*derivation(h, DE)*fd + ba, bd = ba.cancel(fd, include=True) + + G = [(c*A).cancel(D, include=True) for A, D in G] + + return (a, (ba, bd), G, h) + +def real_imag(ba, bd, gen): + """ + Helper function, to get the real and imaginary part of a rational function + evaluated at sqrt(-1) without actually evaluating it at sqrt(-1). + + Explanation + =========== + + Separates the even and odd power terms by checking the degree of terms wrt + mod 4. Returns a tuple (ba[0], ba[1], bd) where ba[0] is real part + of the numerator ba[1] is the imaginary part and bd is the denominator + of the rational function. + """ + bd = bd.as_poly(gen).as_dict() + ba = ba.as_poly(gen).as_dict() + denom_real = [value if key[0] % 4 == 0 else -value if key[0] % 4 == 2 else 0 for key, value in bd.items()] + denom_imag = [value if key[0] % 4 == 1 else -value if key[0] % 4 == 3 else 0 for key, value in bd.items()] + bd_real = sum(r for r in denom_real) + bd_imag = sum(r for r in denom_imag) + num_real = [value if key[0] % 4 == 0 else -value if key[0] % 4 == 2 else 0 for key, value in ba.items()] + num_imag = [value if key[0] % 4 == 1 else -value if key[0] % 4 == 3 else 0 for key, value in ba.items()] + ba_real = sum(r for r in num_real) + ba_imag = sum(r for r in num_imag) + ba = ((ba_real*bd_real + ba_imag*bd_imag).as_poly(gen), (ba_imag*bd_real - ba_real*bd_imag).as_poly(gen)) + bd = (bd_real*bd_real + bd_imag*bd_imag).as_poly(gen) + return (ba[0], ba[1], bd) + + +def prde_special_denom(a, ba, bd, G, DE, case='auto'): + """ + Parametric Risch Differential Equation - Special part of the denominator. + + Explanation + =========== + + Case is one of {'exp', 'tan', 'primitive'} for the hyperexponential, + hypertangent, and primitive cases, respectively. For the hyperexponential + (resp. hypertangent) case, given a derivation D on k[t] and a in k[t], + b in k, and g1, ..., gm in k(t) with Dt/t in k (resp. Dt/(t**2 + 1) in + k, sqrt(-1) not in k), a != 0, and gcd(a, t) == 1 (resp. + gcd(a, t**2 + 1) == 1), return the tuple (A, B, GG, h) such that A, B, h in + k[t], GG = [gg1, ..., ggm] in k(t)^m, and for any solution c1, ..., cm in + Const(k) and q in k of a*Dq + b*q == Sum(ci*gi, (i, 1, m)), r == q*h in + k[t] satisfies A*Dr + B*r == Sum(ci*ggi, (i, 1, m)). + + For case == 'primitive', k == k[t], so it returns (a, b, G, 1) in this + case. + """ + # TODO: Merge this with the very similar special_denom() in rde.py + if case == 'auto': + case = DE.case + + if case == 'exp': + p = Poly(DE.t, DE.t) + elif case == 'tan': + p = Poly(DE.t**2 + 1, DE.t) + elif case in ('primitive', 'base'): + B = ba.quo(bd) + return (a, B, G, Poly(1, DE.t)) + else: + raise ValueError("case must be one of {'exp', 'tan', 'primitive', " + "'base'}, not %s." % case) + + nb = order_at(ba, p, DE.t) - order_at(bd, p, DE.t) + nc = min(order_at(Ga, p, DE.t) - order_at(Gd, p, DE.t) for Ga, Gd in G) + n = min(0, nc - min(0, nb)) + if not nb: + # Possible cancellation. + if case == 'exp': + dcoeff = DE.d.quo(Poly(DE.t, DE.t)) + with DecrementLevel(DE): # We are guaranteed to not have problems, + # because case != 'base'. + alphaa, alphad = frac_in(-ba.eval(0)/bd.eval(0)/a.eval(0), DE.t) + etaa, etad = frac_in(dcoeff, DE.t) + A = parametric_log_deriv(alphaa, alphad, etaa, etad, DE) + if A is not None: + Q, m, z = A + if Q == 1: + n = min(n, m) + + elif case == 'tan': + dcoeff = DE.d.quo(Poly(DE.t**2 + 1, DE.t)) + with DecrementLevel(DE): # We are guaranteed to not have problems, + # because case != 'base'. + betaa, alphaa, alphad = real_imag(ba, bd*a, DE.t) + betad = alphad + etaa, etad = frac_in(dcoeff, DE.t) + if recognize_log_derivative(Poly(2, DE.t)*betaa, betad, DE): + A = parametric_log_deriv(alphaa, alphad, etaa, etad, DE) + B = parametric_log_deriv(betaa, betad, etaa, etad, DE) + if A is not None and B is not None: + Q, s, z = A + # TODO: Add test + if Q == 1: + n = min(n, s/2) + + N = max(0, -nb) + pN = p**N + pn = p**-n # This is 1/h + + A = a*pN + B = ba*pN.quo(bd) + Poly(n, DE.t)*a*derivation(p, DE).quo(p)*pN + G = [(Ga*pN*pn).cancel(Gd, include=True) for Ga, Gd in G] + h = pn + + # (a*p**N, (b + n*a*Dp/p)*p**N, g1*p**(N - n), ..., gm*p**(N - n), p**-n) + return (A, B, G, h) + + +def prde_linear_constraints(a, b, G, DE): + """ + Parametric Risch Differential Equation - Generate linear constraints on the constants. + + Explanation + =========== + + Given a derivation D on k[t], a, b, in k[t] with gcd(a, b) == 1, and + G = [g1, ..., gm] in k(t)^m, return Q = [q1, ..., qm] in k[t]^m and a + matrix M with entries in k(t) such that for any solution c1, ..., cm in + Const(k) and p in k[t] of a*Dp + b*p == Sum(ci*gi, (i, 1, m)), + (c1, ..., cm) is a solution of Mx == 0, and p and the ci satisfy + a*Dp + b*p == Sum(ci*qi, (i, 1, m)). + + Because M has entries in k(t), and because Matrix does not play well with + Poly, M will be a Matrix of Basic expressions. + """ + m = len(G) + + Gns, Gds = list(zip(*G)) + d = reduce(lambda i, j: i.lcm(j), Gds) + d = Poly(d, field=True) + Q = [(ga*(d).quo(gd)).div(d) for ga, gd in G] + + if not all(ri.is_zero for _, ri in Q): + N = max(ri.degree(DE.t) for _, ri in Q) + M = Matrix(N + 1, m, lambda i, j: Q[j][1].nth(i), DE.t) + else: + M = Matrix(0, m, [], DE.t) # No constraints, return the empty matrix. + + qs, _ = list(zip(*Q)) + return (qs, M) + +def poly_linear_constraints(p, d): + """ + Given p = [p1, ..., pm] in k[t]^m and d in k[t], return + q = [q1, ..., qm] in k[t]^m and a matrix M with entries in k such + that Sum(ci*pi, (i, 1, m)), for c1, ..., cm in k, is divisible + by d if and only if (c1, ..., cm) is a solution of Mx = 0, in + which case the quotient is Sum(ci*qi, (i, 1, m)). + """ + m = len(p) + q, r = zip(*[pi.div(d) for pi in p]) + + if not all(ri.is_zero for ri in r): + n = max(ri.degree() for ri in r) + M = Matrix(n + 1, m, lambda i, j: r[j].nth(i), d.gens) + else: + M = Matrix(0, m, [], d.gens) # No constraints. + + return q, M + +def constant_system(A, u, DE): + """ + Generate a system for the constant solutions. + + Explanation + =========== + + Given a differential field (K, D) with constant field C = Const(K), a Matrix + A, and a vector (Matrix) u with coefficients in K, returns the tuple + (B, v, s), where B is a Matrix with coefficients in C and v is a vector + (Matrix) such that either v has coefficients in C, in which case s is True + and the solutions in C of Ax == u are exactly all the solutions of Bx == v, + or v has a non-constant coefficient, in which case s is False Ax == u has no + constant solution. + + This algorithm is used both in solving parametric problems and in + determining if an element a of K is a derivative of an element of K or the + logarithmic derivative of a K-radical using the structure theorem approach. + + Because Poly does not play well with Matrix yet, this algorithm assumes that + all matrix entries are Basic expressions. + """ + if not A: + return A, u + Au = A.row_join(u) + Au, _ = Au.rref() + # Warning: This will NOT return correct results if cancel() cannot reduce + # an identically zero expression to 0. The danger is that we might + # incorrectly prove that an integral is nonelementary (such as + # risch_integrate(exp((sin(x)**2 + cos(x)**2 - 1)*x**2), x). + # But this is a limitation in computer algebra in general, and implicit + # in the correctness of the Risch Algorithm is the computability of the + # constant field (actually, this same correctness problem exists in any + # algorithm that uses rref()). + # + # We therefore limit ourselves to constant fields that are computable + # via the cancel() function, in order to prevent a speed bottleneck from + # calling some more complex simplification function (rational function + # coefficients will fall into this class). Furthermore, (I believe) this + # problem will only crop up if the integral explicitly contains an + # expression in the constant field that is identically zero, but cannot + # be reduced to such by cancel(). Therefore, a careful user can avoid this + # problem entirely by being careful with the sorts of expressions that + # appear in his integrand in the variables other than the integration + # variable (the structure theorems should be able to completely decide these + # problems in the integration variable). + + A, u = Au[:, :-1], Au[:, -1] + + D = lambda x: derivation(x, DE, basic=True) + + for j, i in itertools.product(range(A.cols), range(A.rows)): + if A[i, j].expr.has(*DE.T): + # This assumes that const(F(t0, ..., tn) == const(K) == F + Ri = A[i, :] + # Rm+1; m = A.rows + DAij = D(A[i, j]) + Rm1 = Ri.applyfunc(lambda x: D(x) / DAij) + um1 = D(u[i]) / DAij + + Aj = A[:, j] + A = A - Aj * Rm1 + u = u - Aj * um1 + + A = A.col_join(Rm1) + u = u.col_join(Matrix([um1], u.gens)) + + return (A, u) + + +def prde_spde(a, b, Q, n, DE): + """ + Special Polynomial Differential Equation algorithm: Parametric Version. + + Explanation + =========== + + Given a derivation D on k[t], an integer n, and a, b, q1, ..., qm in k[t] + with deg(a) > 0 and gcd(a, b) == 1, return (A, B, Q, R, n1), with + Qq = [q1, ..., qm] and R = [r1, ..., rm], such that for any solution + c1, ..., cm in Const(k) and q in k[t] of degree at most n of + a*Dq + b*q == Sum(ci*gi, (i, 1, m)), p = (q - Sum(ci*ri, (i, 1, m)))/a has + degree at most n1 and satisfies A*Dp + B*p == Sum(ci*qi, (i, 1, m)) + """ + R, Z = list(zip(*[gcdex_diophantine(b, a, qi) for qi in Q])) + + A = a + B = b + derivation(a, DE) + Qq = [zi - derivation(ri, DE) for ri, zi in zip(R, Z)] + R = list(R) + n1 = n - a.degree(DE.t) + + return (A, B, Qq, R, n1) + + +def prde_no_cancel_b_large(b, Q, n, DE): + """ + Parametric Poly Risch Differential Equation - No cancellation: deg(b) large enough. + + Explanation + =========== + + Given a derivation D on k[t], n in ZZ, and b, q1, ..., qm in k[t] with + b != 0 and either D == d/dt or deg(b) > max(0, deg(D) - 1), returns + h1, ..., hr in k[t] and a matrix A with coefficients in Const(k) such that + if c1, ..., cm in Const(k) and q in k[t] satisfy deg(q) <= n and + Dq + b*q == Sum(ci*qi, (i, 1, m)), then q = Sum(dj*hj, (j, 1, r)), where + d1, ..., dr in Const(k) and A*Matrix([[c1, ..., cm, d1, ..., dr]]).T == 0. + """ + db = b.degree(DE.t) + m = len(Q) + H = [Poly(0, DE.t)]*m + + for N, i in itertools.product(range(n, -1, -1), range(m)): # [n, ..., 0] + si = Q[i].nth(N + db)/b.LC() + sitn = Poly(si*DE.t**N, DE.t) + H[i] = H[i] + sitn + Q[i] = Q[i] - derivation(sitn, DE) - b*sitn + + if all(qi.is_zero for qi in Q): + dc = -1 + else: + dc = max(qi.degree(DE.t) for qi in Q) + M = Matrix(dc + 1, m, lambda i, j: Q[j].nth(i), DE.t) + A, u = constant_system(M, zeros(dc + 1, 1, DE.t), DE) + c = eye(m, DE.t) + A = A.row_join(zeros(A.rows, m, DE.t)).col_join(c.row_join(-c)) + + return (H, A) + + +def prde_no_cancel_b_small(b, Q, n, DE): + """ + Parametric Poly Risch Differential Equation - No cancellation: deg(b) small enough. + + Explanation + =========== + + Given a derivation D on k[t], n in ZZ, and b, q1, ..., qm in k[t] with + deg(b) < deg(D) - 1 and either D == d/dt or deg(D) >= 2, returns + h1, ..., hr in k[t] and a matrix A with coefficients in Const(k) such that + if c1, ..., cm in Const(k) and q in k[t] satisfy deg(q) <= n and + Dq + b*q == Sum(ci*qi, (i, 1, m)) then q = Sum(dj*hj, (j, 1, r)) where + d1, ..., dr in Const(k) and A*Matrix([[c1, ..., cm, d1, ..., dr]]).T == 0. + """ + m = len(Q) + H = [Poly(0, DE.t)]*m + + for N, i in itertools.product(range(n, 0, -1), range(m)): # [n, ..., 1] + si = Q[i].nth(N + DE.d.degree(DE.t) - 1)/(N*DE.d.LC()) + sitn = Poly(si*DE.t**N, DE.t) + H[i] = H[i] + sitn + Q[i] = Q[i] - derivation(sitn, DE) - b*sitn + + if b.degree(DE.t) > 0: + for i in range(m): + si = Poly(Q[i].nth(b.degree(DE.t))/b.LC(), DE.t) + H[i] = H[i] + si + Q[i] = Q[i] - derivation(si, DE) - b*si + if all(qi.is_zero for qi in Q): + dc = -1 + else: + dc = max(qi.degree(DE.t) for qi in Q) + M = Matrix(dc + 1, m, lambda i, j: Q[j].nth(i), DE.t) + A, u = constant_system(M, zeros(dc + 1, 1, DE.t), DE) + c = eye(m, DE.t) + A = A.row_join(zeros(A.rows, m, DE.t)).col_join(c.row_join(-c)) + return (H, A) + + # else: b is in k, deg(qi) < deg(Dt) + + t = DE.t + if DE.case != 'base': + with DecrementLevel(DE): + t0 = DE.t # k = k0(t0) + ba, bd = frac_in(b, t0, field=True) + Q0 = [frac_in(qi.TC(), t0, field=True) for qi in Q] + f, B = param_rischDE(ba, bd, Q0, DE) + + # f = [f1, ..., fr] in k^r and B is a matrix with + # m + r columns and entries in Const(k) = Const(k0) + # such that Dy0 + b*y0 = Sum(ci*qi, (i, 1, m)) has + # a solution y0 in k with c1, ..., cm in Const(k) + # if and only y0 = Sum(dj*fj, (j, 1, r)) where + # d1, ..., dr ar in Const(k) and + # B*Matrix([c1, ..., cm, d1, ..., dr]) == 0. + + # Transform fractions (fa, fd) in f into constant + # polynomials fa/fd in k[t]. + # (Is there a better way?) + f = [Poly(fa.as_expr()/fd.as_expr(), t, field=True) + for fa, fd in f] + B = Matrix.from_Matrix(B.to_Matrix(), t) + else: + # Base case. Dy == 0 for all y in k and b == 0. + # Dy + b*y = Sum(ci*qi) is solvable if and only if + # Sum(ci*qi) == 0 in which case the solutions are + # y = d1*f1 for f1 = 1 and any d1 in Const(k) = k. + + f = [Poly(1, t, field=True)] # r = 1 + B = Matrix([[qi.TC() for qi in Q] + [S.Zero]], DE.t) + # The condition for solvability is + # B*Matrix([c1, ..., cm, d1]) == 0 + # There are no constraints on d1. + + # Coefficients of t^j (j > 0) in Sum(ci*qi) must be zero. + d = max(qi.degree(DE.t) for qi in Q) + if d > 0: + M = Matrix(d, m, lambda i, j: Q[j].nth(i + 1), DE.t) + A, _ = constant_system(M, zeros(d, 1, DE.t), DE) + else: + # No constraints on the hj. + A = Matrix(0, m, [], DE.t) + + # Solutions of the original equation are + # y = Sum(dj*fj, (j, 1, r) + Sum(ei*hi, (i, 1, m)), + # where ei == ci (i = 1, ..., m), when + # A*Matrix([c1, ..., cm]) == 0 and + # B*Matrix([c1, ..., cm, d1, ..., dr]) == 0 + + # Build combined constraint matrix with m + r + m columns. + + r = len(f) + I = eye(m, DE.t) + A = A.row_join(zeros(A.rows, r + m, DE.t)) + B = B.row_join(zeros(B.rows, m, DE.t)) + C = I.row_join(zeros(m, r, DE.t)).row_join(-I) + + return f + H, A.col_join(B).col_join(C) + + +def prde_cancel_liouvillian(b, Q, n, DE): + """ + Pg, 237. + """ + H = [] + + # Why use DecrementLevel? Below line answers that: + # Assuming that we can solve such problems over 'k' (not k[t]) + if DE.case == 'primitive': + with DecrementLevel(DE): + ba, bd = frac_in(b, DE.t, field=True) + + for i in range(n, -1, -1): + if DE.case == 'exp': # this re-checking can be avoided + with DecrementLevel(DE): + ba, bd = frac_in(b + (i*(derivation(DE.t, DE)/DE.t)).as_poly(b.gens), + DE.t, field=True) + with DecrementLevel(DE): + Qy = [frac_in(q.nth(i), DE.t, field=True) for q in Q] + fi, Ai = param_rischDE(ba, bd, Qy, DE) + fi = [Poly(fa.as_expr()/fd.as_expr(), DE.t, field=True) + for fa, fd in fi] + Ai = Ai.set_gens(DE.t) + + ri = len(fi) + + if i == n: + M = Ai + else: + M = Ai.col_join(M.row_join(zeros(M.rows, ri, DE.t))) + + Fi, hi = [None]*ri, [None]*ri + + # from eq. on top of p.238 (unnumbered) + for j in range(ri): + hji = fi[j] * (DE.t**i).as_poly(fi[j].gens) + hi[j] = hji + # building up Sum(djn*(D(fjn*t^n) - b*fjnt^n)) + Fi[j] = -(derivation(hji, DE) - b*hji) + + H += hi + # in the next loop instead of Q it has + # to be Q + Fi taking its place + Q = Q + Fi + + return (H, M) + + +def param_poly_rischDE(a, b, q, n, DE): + """Polynomial solutions of a parametric Risch differential equation. + + Explanation + =========== + + Given a derivation D in k[t], a, b in k[t] relatively prime, and q + = [q1, ..., qm] in k[t]^m, return h = [h1, ..., hr] in k[t]^r and + a matrix A with m + r columns and entries in Const(k) such that + a*Dp + b*p = Sum(ci*qi, (i, 1, m)) has a solution p of degree <= n + in k[t] with c1, ..., cm in Const(k) if and only if p = Sum(dj*hj, + (j, 1, r)) where d1, ..., dr are in Const(k) and (c1, ..., cm, + d1, ..., dr) is a solution of Ax == 0. + """ + m = len(q) + if n < 0: + # Only the trivial zero solution is possible. + # Find relations between the qi. + if all(qi.is_zero for qi in q): + return [], zeros(1, m, DE.t) # No constraints. + + N = max(qi.degree(DE.t) for qi in q) + M = Matrix(N + 1, m, lambda i, j: q[j].nth(i), DE.t) + A, _ = constant_system(M, zeros(M.rows, 1, DE.t), DE) + + return [], A + + if a.is_ground: + # Normalization: a = 1. + a = a.LC() + b, q = b.to_field().exquo_ground(a), [qi.to_field().exquo_ground(a) for qi in q] + + if not b.is_zero and (DE.case == 'base' or + b.degree() > max(0, DE.d.degree() - 1)): + return prde_no_cancel_b_large(b, q, n, DE) + + elif ((b.is_zero or b.degree() < DE.d.degree() - 1) + and (DE.case == 'base' or DE.d.degree() >= 2)): + return prde_no_cancel_b_small(b, q, n, DE) + + elif (DE.d.degree() >= 2 and + b.degree() == DE.d.degree() - 1 and + n > -b.as_poly().LC()/DE.d.as_poly().LC()): + raise NotImplementedError("prde_no_cancel_b_equal() is " + "not yet implemented.") + + else: + # Liouvillian cases + if DE.case in ('primitive', 'exp'): + return prde_cancel_liouvillian(b, q, n, DE) + else: + raise NotImplementedError("non-linear and hypertangent " + "cases have not yet been implemented") + + # else: deg(a) > 0 + + # Iterate SPDE as long as possible cumulating coefficient + # and terms for the recovery of original solutions. + alpha, beta = a.one, [a.zero]*m + while n >= 0: # and a, b relatively prime + a, b, q, r, n = prde_spde(a, b, q, n, DE) + beta = [betai + alpha*ri for betai, ri in zip(beta, r)] + alpha *= a + # Solutions p of a*Dp + b*p = Sum(ci*qi) correspond to + # solutions alpha*p + Sum(ci*betai) of the initial equation. + d = a.gcd(b) + if not d.is_ground: + break + + # a*Dp + b*p = Sum(ci*qi) may have a polynomial solution + # only if the sum is divisible by d. + + qq, M = poly_linear_constraints(q, d) + # qq = [qq1, ..., qqm] where qqi = qi.quo(d). + # M is a matrix with m columns an entries in k. + # Sum(fi*qi, (i, 1, m)), where f1, ..., fm are elements of k, is + # divisible by d if and only if M*Matrix([f1, ..., fm]) == 0, + # in which case the quotient is Sum(fi*qqi). + + A, _ = constant_system(M, zeros(M.rows, 1, DE.t), DE) + # A is a matrix with m columns and entries in Const(k). + # Sum(ci*qqi) is Sum(ci*qi).quo(d), and the remainder is zero + # for c1, ..., cm in Const(k) if and only if + # A*Matrix([c1, ...,cm]) == 0. + + V = A.nullspace() + # V = [v1, ..., vu] where each vj is a column matrix with + # entries aj1, ..., ajm in Const(k). + # Sum(aji*qi) is divisible by d with exact quotient Sum(aji*qqi). + # Sum(ci*qi) is divisible by d if and only if ci = Sum(dj*aji) + # (i = 1, ..., m) for some d1, ..., du in Const(k). + # In that case, solutions of + # a*Dp + b*p = Sum(ci*qi) = Sum(dj*Sum(aji*qi)) + # are the same as those of + # (a/d)*Dp + (b/d)*p = Sum(dj*rj) + # where rj = Sum(aji*qqi). + + if not V: # No non-trivial solution. + return [], eye(m, DE.t) # Could return A, but this has + # the minimum number of rows. + + Mqq = Matrix([qq]) # A single row. + r = [(Mqq*vj)[0] for vj in V] # [r1, ..., ru] + + # Solutions of (a/d)*Dp + (b/d)*p = Sum(dj*rj) correspond to + # solutions alpha*p + Sum(Sum(dj*aji)*betai) of the initial + # equation. These are equal to alpha*p + Sum(dj*fj) where + # fj = Sum(aji*betai). + Mbeta = Matrix([beta]) + f = [(Mbeta*vj)[0] for vj in V] # [f1, ..., fu] + + # + # Solve the reduced equation recursively. + # + g, B = param_poly_rischDE(a.quo(d), b.quo(d), r, n, DE) + + # g = [g1, ..., gv] in k[t]^v and and B is a matrix with u + v + # columns and entries in Const(k) such that + # (a/d)*Dp + (b/d)*p = Sum(dj*rj) has a solution p of degree <= n + # in k[t] if and only if p = Sum(ek*gk) where e1, ..., ev are in + # Const(k) and B*Matrix([d1, ..., du, e1, ..., ev]) == 0. + # The solutions of the original equation are then + # Sum(dj*fj, (j, 1, u)) + alpha*Sum(ek*gk, (k, 1, v)). + + # Collect solution components. + h = f + [alpha*gk for gk in g] + + # Build combined relation matrix. + A = -eye(m, DE.t) + for vj in V: + A = A.row_join(vj) + A = A.row_join(zeros(m, len(g), DE.t)) + A = A.col_join(zeros(B.rows, m, DE.t).row_join(B)) + + return h, A + + +def param_rischDE(fa, fd, G, DE): + """ + Solve a Parametric Risch Differential Equation: Dy + f*y == Sum(ci*Gi, (i, 1, m)). + + Explanation + =========== + + Given a derivation D in k(t), f in k(t), and G + = [G1, ..., Gm] in k(t)^m, return h = [h1, ..., hr] in k(t)^r and + a matrix A with m + r columns and entries in Const(k) such that + Dy + f*y = Sum(ci*Gi, (i, 1, m)) has a solution y + in k(t) with c1, ..., cm in Const(k) if and only if y = Sum(dj*hj, + (j, 1, r)) where d1, ..., dr are in Const(k) and (c1, ..., cm, + d1, ..., dr) is a solution of Ax == 0. + + Elements of k(t) are tuples (a, d) with a and d in k[t]. + """ + m = len(G) + q, (fa, fd) = weak_normalizer(fa, fd, DE) + # Solutions of the weakly normalized equation Dz + f*z = q*Sum(ci*Gi) + # correspond to solutions y = z/q of the original equation. + gamma = q + G = [(q*ga).cancel(gd, include=True) for ga, gd in G] + + a, (ba, bd), G, hn = prde_normal_denom(fa, fd, G, DE) + # Solutions q in k of a*Dq + b*q = Sum(ci*Gi) correspond + # to solutions z = q/hn of the weakly normalized equation. + gamma *= hn + + A, B, G, hs = prde_special_denom(a, ba, bd, G, DE) + # Solutions p in k[t] of A*Dp + B*p = Sum(ci*Gi) correspond + # to solutions q = p/hs of the previous equation. + gamma *= hs + + g = A.gcd(B) + a, b, g = A.quo(g), B.quo(g), [gia.cancel(gid*g, include=True) for + gia, gid in G] + + # a*Dp + b*p = Sum(ci*gi) may have a polynomial solution + # only if the sum is in k[t]. + + q, M = prde_linear_constraints(a, b, g, DE) + + # q = [q1, ..., qm] where qi in k[t] is the polynomial component + # of the partial fraction expansion of gi. + # M is a matrix with m columns and entries in k. + # Sum(fi*gi, (i, 1, m)), where f1, ..., fm are elements of k, + # is a polynomial if and only if M*Matrix([f1, ..., fm]) == 0, + # in which case the sum is equal to Sum(fi*qi). + + M, _ = constant_system(M, zeros(M.rows, 1, DE.t), DE) + # M is a matrix with m columns and entries in Const(k). + # Sum(ci*gi) is in k[t] for c1, ..., cm in Const(k) + # if and only if M*Matrix([c1, ..., cm]) == 0, + # in which case the sum is Sum(ci*qi). + + ## Reduce number of constants at this point + + V = M.nullspace() + # V = [v1, ..., vu] where each vj is a column matrix with + # entries aj1, ..., ajm in Const(k). + # Sum(aji*gi) is in k[t] and equal to Sum(aji*qi) (j = 1, ..., u). + # Sum(ci*gi) is in k[t] if and only is ci = Sum(dj*aji) + # (i = 1, ..., m) for some d1, ..., du in Const(k). + # In that case, + # Sum(ci*gi) = Sum(ci*qi) = Sum(dj*Sum(aji*qi)) = Sum(dj*rj) + # where rj = Sum(aji*qi) (j = 1, ..., u) in k[t]. + + if not V: # No non-trivial solution + return [], eye(m, DE.t) + + Mq = Matrix([q]) # A single row. + r = [(Mq*vj)[0] for vj in V] # [r1, ..., ru] + + # Solutions of a*Dp + b*p = Sum(dj*rj) correspond to solutions + # y = p/gamma of the initial equation with ci = Sum(dj*aji). + + try: + # We try n=5. At least for prde_spde, it will always + # terminate no matter what n is. + n = bound_degree(a, b, r, DE, parametric=True) + except NotImplementedError: + # A temporary bound is set. Eventually, it will be removed. + # the currently added test case takes large time + # even with n=5, and much longer with large n's. + n = 5 + + h, B = param_poly_rischDE(a, b, r, n, DE) + + # h = [h1, ..., hv] in k[t]^v and and B is a matrix with u + v + # columns and entries in Const(k) such that + # a*Dp + b*p = Sum(dj*rj) has a solution p of degree <= n + # in k[t] if and only if p = Sum(ek*hk) where e1, ..., ev are in + # Const(k) and B*Matrix([d1, ..., du, e1, ..., ev]) == 0. + # The solutions of the original equation for ci = Sum(dj*aji) + # (i = 1, ..., m) are then y = Sum(ek*hk, (k, 1, v))/gamma. + + ## Build combined relation matrix with m + u + v columns. + + A = -eye(m, DE.t) + for vj in V: + A = A.row_join(vj) + A = A.row_join(zeros(m, len(h), DE.t)) + A = A.col_join(zeros(B.rows, m, DE.t).row_join(B)) + + ## Eliminate d1, ..., du. + + W = A.nullspace() + + # W = [w1, ..., wt] where each wl is a column matrix with + # entries blk (k = 1, ..., m + u + v) in Const(k). + # The vectors (bl1, ..., blm) generate the space of those + # constant families (c1, ..., cm) for which a solution of + # the equation Dy + f*y == Sum(ci*Gi) exists. They generate + # the space and form a basis except possibly when Dy + f*y == 0 + # is solvable in k(t}. The corresponding solutions are + # y = Sum(blk'*hk, (k, 1, v))/gamma, where k' = k + m + u. + + v = len(h) + shape = (len(W), m+v) + elements = [wl[:m] + wl[-v:] for wl in W] # excise dj's. + items = [e for row in elements for e in row] + + # Need to set the shape in case W is empty + M = Matrix(*shape, items, DE.t) + N = M.nullspace() + + # N = [n1, ..., ns] where the ni in Const(k)^(m + v) are column + # vectors generating the space of linear relations between + # c1, ..., cm, e1, ..., ev. + + C = Matrix([ni[:] for ni in N], DE.t) # rows n1, ..., ns. + + return [hk.cancel(gamma, include=True) for hk in h], C + + +def limited_integrate_reduce(fa, fd, G, DE): + """ + Simpler version of step 1 & 2 for the limited integration problem. + + Explanation + =========== + + Given a derivation D on k(t) and f, g1, ..., gn in k(t), return + (a, b, h, N, g, V) such that a, b, h in k[t], N is a non-negative integer, + g in k(t), V == [v1, ..., vm] in k(t)^m, and for any solution v in k(t), + c1, ..., cm in C of f == Dv + Sum(ci*wi, (i, 1, m)), p = v*h is in k, and + p and the ci satisfy a*Dp + b*p == g + Sum(ci*vi, (i, 1, m)). Furthermore, + if S1irr == Sirr, then p is in k[t], and if t is nonlinear or Liouvillian + over k, then deg(p) <= N. + + So that the special part is always computed, this function calls the more + general prde_special_denom() automatically if it cannot determine that + S1irr == Sirr. Furthermore, it will automatically call bound_degree() when + t is linear and non-Liouvillian, which for the transcendental case, implies + that Dt == a*t + b with for some a, b in k*. + """ + dn, ds = splitfactor(fd, DE) + E = [splitfactor(gd, DE) for _, gd in G] + En, Es = list(zip(*E)) + c = reduce(lambda i, j: i.lcm(j), (dn,) + En) # lcm(dn, en1, ..., enm) + hn = c.gcd(c.diff(DE.t)) + a = hn + b = -derivation(hn, DE) + N = 0 + + # These are the cases where we know that S1irr = Sirr, but there could be + # others, and this algorithm will need to be extended to handle them. + if DE.case in ('base', 'primitive', 'exp', 'tan'): + hs = reduce(lambda i, j: i.lcm(j), (ds,) + Es) # lcm(ds, es1, ..., esm) + a = hn*hs + b -= (hn*derivation(hs, DE)).quo(hs) + mu = min(order_at_oo(fa, fd, DE.t), min(order_at_oo(ga, gd, DE.t) for + ga, gd in G)) + # So far, all the above are also nonlinear or Liouvillian, but if this + # changes, then this will need to be updated to call bound_degree() + # as per the docstring of this function (DE.case == 'other_linear'). + N = hn.degree(DE.t) + hs.degree(DE.t) + max(0, 1 - DE.d.degree(DE.t) - mu) + else: + # TODO: implement this + raise NotImplementedError + + V = [(-a*hn*ga).cancel(gd, include=True) for ga, gd in G] + return (a, b, a, N, (a*hn*fa).cancel(fd, include=True), V) + + +def limited_integrate(fa, fd, G, DE): + """ + Solves the limited integration problem: f = Dv + Sum(ci*wi, (i, 1, n)) + """ + fa, fd = fa*Poly(1/fd.LC(), DE.t), fd.monic() + # interpreting limited integration problem as a + # parametric Risch DE problem + Fa = Poly(0, DE.t) + Fd = Poly(1, DE.t) + G = [(fa, fd)] + G + h, A = param_rischDE(Fa, Fd, G, DE) + V = A.nullspace() + V = [v for v in V if v[0] != 0] + if not V: + return None + else: + # we can take any vector from V, we take V[0] + c0 = V[0][0] + # v = [-1, c1, ..., cm, d1, ..., dr] + v = V[0]/(-c0) + r = len(h) + m = len(v) - r - 1 + C = list(v[1: m + 1]) + y = -sum(v[m + 1 + i]*h[i][0].as_expr()/h[i][1].as_expr() \ + for i in range(r)) + y_num, y_den = y.as_numer_denom() + Ya, Yd = Poly(y_num, DE.t), Poly(y_den, DE.t) + Y = Ya*Poly(1/Yd.LC(), DE.t), Yd.monic() + return Y, C + + +def parametric_log_deriv_heu(fa, fd, wa, wd, DE, c1=None): + """ + Parametric logarithmic derivative heuristic. + + Explanation + =========== + + Given a derivation D on k[t], f in k(t), and a hyperexponential monomial + theta over k(t), raises either NotImplementedError, in which case the + heuristic failed, or returns None, in which case it has proven that no + solution exists, or returns a solution (n, m, v) of the equation + n*f == Dv/v + m*Dtheta/theta, with v in k(t)* and n, m in ZZ with n != 0. + + If this heuristic fails, the structure theorem approach will need to be + used. + + The argument w == Dtheta/theta + """ + # TODO: finish writing this and write tests + c1 = c1 or Dummy('c1') + + p, a = fa.div(fd) + q, b = wa.div(wd) + + B = max(0, derivation(DE.t, DE).degree(DE.t) - 1) + C = max(p.degree(DE.t), q.degree(DE.t)) + + if q.degree(DE.t) > B: + eqs = [p.nth(i) - c1*q.nth(i) for i in range(B + 1, C + 1)] + s = solve(eqs, c1) + if not s or not s[c1].is_Rational: + # deg(q) > B, no solution for c. + return None + + M, N = s[c1].as_numer_denom() + M_poly = M.as_poly(q.gens) + N_poly = N.as_poly(q.gens) + + nfmwa = N_poly*fa*wd - M_poly*wa*fd + nfmwd = fd*wd + Qv = is_log_deriv_k_t_radical_in_field(nfmwa, nfmwd, DE, 'auto') + if Qv is None: + # (N*f - M*w) is not the logarithmic derivative of a k(t)-radical. + return None + + Q, v = Qv + + if Q.is_zero or v.is_zero: + return None + + return (Q*N, Q*M, v) + + if p.degree(DE.t) > B: + return None + + c = lcm(fd.as_poly(DE.t).LC(), wd.as_poly(DE.t).LC()) + l = fd.monic().lcm(wd.monic())*Poly(c, DE.t) + ln, ls = splitfactor(l, DE) + z = ls*ln.gcd(ln.diff(DE.t)) + + if not z.has(DE.t): + # TODO: We treat this as 'no solution', until the structure + # theorem version of parametric_log_deriv is implemented. + return None + + u1, r1 = (fa*l.quo(fd)).div(z) # (l*f).div(z) + u2, r2 = (wa*l.quo(wd)).div(z) # (l*w).div(z) + + eqs = [r1.nth(i) - c1*r2.nth(i) for i in range(z.degree(DE.t))] + s = solve(eqs, c1) + if not s or not s[c1].is_Rational: + # deg(q) <= B, no solution for c. + return None + + M, N = s[c1].as_numer_denom() + + nfmwa = N.as_poly(DE.t)*fa*wd - M.as_poly(DE.t)*wa*fd + nfmwd = fd*wd + Qv = is_log_deriv_k_t_radical_in_field(nfmwa, nfmwd, DE) + if Qv is None: + # (N*f - M*w) is not the logarithmic derivative of a k(t)-radical. + return None + + Q, v = Qv + + if Q.is_zero or v.is_zero: + return None + + return (Q*N, Q*M, v) + + +def parametric_log_deriv(fa, fd, wa, wd, DE): + # TODO: Write the full algorithm using the structure theorems. +# try: + A = parametric_log_deriv_heu(fa, fd, wa, wd, DE) +# except NotImplementedError: + # Heuristic failed, we have to use the full method. + # TODO: This could be implemented more efficiently. + # It isn't too worrisome, because the heuristic handles most difficult + # cases. + return A + + +def is_deriv_k(fa, fd, DE): + r""" + Checks if Df/f is the derivative of an element of k(t). + + Explanation + =========== + + a in k(t) is the derivative of an element of k(t) if there exists b in k(t) + such that a = Db. Either returns (ans, u), such that Df/f == Du, or None, + which means that Df/f is not the derivative of an element of k(t). ans is + a list of tuples such that Add(*[i*j for i, j in ans]) == u. This is useful + for seeing exactly which elements of k(t) produce u. + + This function uses the structure theorem approach, which says that for any + f in K, Df/f is the derivative of a element of K if and only if there are ri + in QQ such that:: + + --- --- Dt + \ r * Dt + \ r * i Df + / i i / i --- = --. + --- --- t f + i in L i in E i + K/C(x) K/C(x) + + + Where C = Const(K), L_K/C(x) = { i in {1, ..., n} such that t_i is + transcendental over C(x)(t_1, ..., t_i-1) and Dt_i = Da_i/a_i, for some a_i + in C(x)(t_1, ..., t_i-1)* } (i.e., the set of all indices of logarithmic + monomials of K over C(x)), and E_K/C(x) = { i in {1, ..., n} such that t_i + is transcendental over C(x)(t_1, ..., t_i-1) and Dt_i/t_i = Da_i, for some + a_i in C(x)(t_1, ..., t_i-1) } (i.e., the set of all indices of + hyperexponential monomials of K over C(x)). If K is an elementary extension + over C(x), then the cardinality of L_K/C(x) U E_K/C(x) is exactly the + transcendence degree of K over C(x). Furthermore, because Const_D(K) == + Const_D(C(x)) == C, deg(Dt_i) == 1 when t_i is in E_K/C(x) and + deg(Dt_i) == 0 when t_i is in L_K/C(x), implying in particular that E_K/C(x) + and L_K/C(x) are disjoint. + + The sets L_K/C(x) and E_K/C(x) must, by their nature, be computed + recursively using this same function. Therefore, it is required to pass + them as indices to D (or T). E_args are the arguments of the + hyperexponentials indexed by E_K (i.e., if i is in E_K, then T[i] == + exp(E_args[i])). This is needed to compute the final answer u such that + Df/f == Du. + + log(f) will be the same as u up to a additive constant. This is because + they will both behave the same as monomials. For example, both log(x) and + log(2*x) == log(x) + log(2) satisfy Dt == 1/x, because log(2) is constant. + Therefore, the term const is returned. const is such that + log(const) + f == u. This is calculated by dividing the arguments of one + logarithm from the other. Therefore, it is necessary to pass the arguments + of the logarithmic terms in L_args. + + To handle the case where we are given Df/f, not f, use is_deriv_k_in_field(). + + See also + ======== + is_log_deriv_k_t_radical_in_field, is_log_deriv_k_t_radical + + """ + # Compute Df/f + dfa, dfd = (fd*derivation(fa, DE) - fa*derivation(fd, DE)), fd*fa + dfa, dfd = dfa.cancel(dfd, include=True) + + # Our assumption here is that each monomial is recursively transcendental + if len(DE.exts) != len(DE.D): + if [i for i in DE.cases if i == 'tan'] or \ + ({i for i in DE.cases if i == 'primitive'} - + set(DE.indices('log'))): + raise NotImplementedError("Real version of the structure " + "theorems with hypertangent support is not yet implemented.") + + # TODO: What should really be done in this case? + raise NotImplementedError("Nonelementary extensions not supported " + "in the structure theorems.") + + E_part = [DE.D[i].quo(Poly(DE.T[i], DE.T[i])).as_expr() for i in DE.indices('exp')] + L_part = [DE.D[i].as_expr() for i in DE.indices('log')] + + # The expression dfa/dfd might not be polynomial in any of its symbols so we + # use a Dummy as the generator for PolyMatrix. + dum = Dummy() + lhs = Matrix([E_part + L_part], dum) + rhs = Matrix([dfa.as_expr()/dfd.as_expr()], dum) + + A, u = constant_system(lhs, rhs, DE) + + u = u.to_Matrix() # Poly to Expr + + if not A or not all(derivation(i, DE, basic=True).is_zero for i in u): + # If the elements of u are not all constant + # Note: See comment in constant_system + + # Also note: derivation(basic=True) calls cancel() + return None + else: + if not all(i.is_Rational for i in u): + raise NotImplementedError("Cannot work with non-rational " + "coefficients in this case.") + else: + terms = ([DE.extargs[i] for i in DE.indices('exp')] + + [DE.T[i] for i in DE.indices('log')]) + ans = list(zip(terms, u)) + result = Add(*[Mul(i, j) for i, j in ans]) + argterms = ([DE.T[i] for i in DE.indices('exp')] + + [DE.extargs[i] for i in DE.indices('log')]) + l = [] + ld = [] + for i, j in zip(argterms, u): + # We need to get around things like sqrt(x**2) != x + # and also sqrt(x**2 + 2*x + 1) != x + 1 + # Issue 10798: i need not be a polynomial + i, d = i.as_numer_denom() + icoeff, iterms = sqf_list(i) + l.append(Mul(*([Pow(icoeff, j)] + [Pow(b, e*j) for b, e in iterms]))) + dcoeff, dterms = sqf_list(d) + ld.append(Mul(*([Pow(dcoeff, j)] + [Pow(b, e*j) for b, e in dterms]))) + const = cancel(fa.as_expr()/fd.as_expr()/Mul(*l)*Mul(*ld)) + + return (ans, result, const) + + +def is_log_deriv_k_t_radical(fa, fd, DE, Df=True): + r""" + Checks if Df is the logarithmic derivative of a k(t)-radical. + + Explanation + =========== + + b in k(t) can be written as the logarithmic derivative of a k(t) radical if + there exist n in ZZ and u in k(t) with n, u != 0 such that n*b == Du/u. + Either returns (ans, u, n, const) or None, which means that Df cannot be + written as the logarithmic derivative of a k(t)-radical. ans is a list of + tuples such that Mul(*[i**j for i, j in ans]) == u. This is useful for + seeing exactly what elements of k(t) produce u. + + This function uses the structure theorem approach, which says that for any + f in K, Df is the logarithmic derivative of a K-radical if and only if there + are ri in QQ such that:: + + --- --- Dt + \ r * Dt + \ r * i + / i i / i --- = Df. + --- --- t + i in L i in E i + K/C(x) K/C(x) + + + Where C = Const(K), L_K/C(x) = { i in {1, ..., n} such that t_i is + transcendental over C(x)(t_1, ..., t_i-1) and Dt_i = Da_i/a_i, for some a_i + in C(x)(t_1, ..., t_i-1)* } (i.e., the set of all indices of logarithmic + monomials of K over C(x)), and E_K/C(x) = { i in {1, ..., n} such that t_i + is transcendental over C(x)(t_1, ..., t_i-1) and Dt_i/t_i = Da_i, for some + a_i in C(x)(t_1, ..., t_i-1) } (i.e., the set of all indices of + hyperexponential monomials of K over C(x)). If K is an elementary extension + over C(x), then the cardinality of L_K/C(x) U E_K/C(x) is exactly the + transcendence degree of K over C(x). Furthermore, because Const_D(K) == + Const_D(C(x)) == C, deg(Dt_i) == 1 when t_i is in E_K/C(x) and + deg(Dt_i) == 0 when t_i is in L_K/C(x), implying in particular that E_K/C(x) + and L_K/C(x) are disjoint. + + The sets L_K/C(x) and E_K/C(x) must, by their nature, be computed + recursively using this same function. Therefore, it is required to pass + them as indices to D (or T). L_args are the arguments of the logarithms + indexed by L_K (i.e., if i is in L_K, then T[i] == log(L_args[i])). This is + needed to compute the final answer u such that n*f == Du/u. + + exp(f) will be the same as u up to a multiplicative constant. This is + because they will both behave the same as monomials. For example, both + exp(x) and exp(x + 1) == E*exp(x) satisfy Dt == t. Therefore, the term const + is returned. const is such that exp(const)*f == u. This is calculated by + subtracting the arguments of one exponential from the other. Therefore, it + is necessary to pass the arguments of the exponential terms in E_args. + + To handle the case where we are given Df, not f, use + is_log_deriv_k_t_radical_in_field(). + + See also + ======== + + is_log_deriv_k_t_radical_in_field, is_deriv_k + + """ + if Df: + dfa, dfd = (fd*derivation(fa, DE) - fa*derivation(fd, DE)).cancel(fd**2, + include=True) + else: + dfa, dfd = fa, fd + + # Our assumption here is that each monomial is recursively transcendental + if len(DE.exts) != len(DE.D): + if [i for i in DE.cases if i == 'tan'] or \ + ({i for i in DE.cases if i == 'primitive'} - + set(DE.indices('log'))): + raise NotImplementedError("Real version of the structure " + "theorems with hypertangent support is not yet implemented.") + + # TODO: What should really be done in this case? + raise NotImplementedError("Nonelementary extensions not supported " + "in the structure theorems.") + + E_part = [DE.D[i].quo(Poly(DE.T[i], DE.T[i])).as_expr() for i in DE.indices('exp')] + L_part = [DE.D[i].as_expr() for i in DE.indices('log')] + + # The expression dfa/dfd might not be polynomial in any of its symbols so we + # use a Dummy as the generator for PolyMatrix. + dum = Dummy() + lhs = Matrix([E_part + L_part], dum) + rhs = Matrix([dfa.as_expr()/dfd.as_expr()], dum) + + A, u = constant_system(lhs, rhs, DE) + + u = u.to_Matrix() # Poly to Expr + + if not A or not all(derivation(i, DE, basic=True).is_zero for i in u): + # If the elements of u are not all constant + # Note: See comment in constant_system + + # Also note: derivation(basic=True) calls cancel() + return None + else: + if not all(i.is_Rational for i in u): + # TODO: But maybe we can tell if they're not rational, like + # log(2)/log(3). Also, there should be an option to continue + # anyway, even if the result might potentially be wrong. + raise NotImplementedError("Cannot work with non-rational " + "coefficients in this case.") + else: + n = S.One*reduce(ilcm, [i.as_numer_denom()[1] for i in u]) + u *= n + terms = ([DE.T[i] for i in DE.indices('exp')] + + [DE.extargs[i] for i in DE.indices('log')]) + ans = list(zip(terms, u)) + result = Mul(*[Pow(i, j) for i, j in ans]) + + # exp(f) will be the same as result up to a multiplicative + # constant. We now find the log of that constant. + argterms = ([DE.extargs[i] for i in DE.indices('exp')] + + [DE.T[i] for i in DE.indices('log')]) + const = cancel(fa.as_expr()/fd.as_expr() - + Add(*[Mul(i, j/n) for i, j in zip(argterms, u)])) + + return (ans, result, n, const) + + +def is_log_deriv_k_t_radical_in_field(fa, fd, DE, case='auto', z=None): + """ + Checks if f can be written as the logarithmic derivative of a k(t)-radical. + + Explanation + =========== + + It differs from is_log_deriv_k_t_radical(fa, fd, DE, Df=False) + for any given fa, fd, DE in that it finds the solution in the + given field not in some (possibly unspecified extension) and + "in_field" with the function name is used to indicate that. + + f in k(t) can be written as the logarithmic derivative of a k(t) radical if + there exist n in ZZ and u in k(t) with n, u != 0 such that n*f == Du/u. + Either returns (n, u) or None, which means that f cannot be written as the + logarithmic derivative of a k(t)-radical. + + case is one of {'primitive', 'exp', 'tan', 'auto'} for the primitive, + hyperexponential, and hypertangent cases, respectively. If case is 'auto', + it will attempt to determine the type of the derivation automatically. + + See also + ======== + is_log_deriv_k_t_radical, is_deriv_k + + """ + fa, fd = fa.cancel(fd, include=True) + + # f must be simple + n, s = splitfactor(fd, DE) + if not s.is_one: + pass + + z = z or Dummy('z') + H, b = residue_reduce(fa, fd, DE, z=z) + if not b: + # I will have to verify, but I believe that the answer should be + # None in this case. This should never happen for the + # functions given when solving the parametric logarithmic + # derivative problem when integration elementary functions (see + # Bronstein's book, page 255), so most likely this indicates a bug. + return None + + roots = [(i, i.real_roots()) for i, _ in H] + if not all(len(j) == i.degree() and all(k.is_Rational for k in j) for + i, j in roots): + # If f is the logarithmic derivative of a k(t)-radical, then all the + # roots of the resultant must be rational numbers. + return None + + # [(a, i), ...], where i*log(a) is a term in the log-part of the integral + # of f + respolys, residues = list(zip(*roots)) or [[], []] + # Note: this might be empty, but everything below should work find in that + # case (it should be the same as if it were [[1, 1]]) + residueterms = [(H[j][1].subs(z, i), i) for j in range(len(H)) for + i in residues[j]] + + # TODO: finish writing this and write tests + + p = cancel(fa.as_expr()/fd.as_expr() - residue_reduce_derivation(H, DE, z)) + + p = p.as_poly(DE.t) + if p is None: + # f - Dg will be in k[t] if f is the logarithmic derivative of a k(t)-radical + return None + + if p.degree(DE.t) >= max(1, DE.d.degree(DE.t)): + return None + + if case == 'auto': + case = DE.case + + if case == 'exp': + wa, wd = derivation(DE.t, DE).cancel(Poly(DE.t, DE.t), include=True) + with DecrementLevel(DE): + pa, pd = frac_in(p, DE.t, cancel=True) + wa, wd = frac_in((wa, wd), DE.t) + A = parametric_log_deriv(pa, pd, wa, wd, DE) + if A is None: + return None + n, e, u = A + u *= DE.t**e + + elif case == 'primitive': + with DecrementLevel(DE): + pa, pd = frac_in(p, DE.t) + A = is_log_deriv_k_t_radical_in_field(pa, pd, DE, case='auto') + if A is None: + return None + n, u = A + + elif case == 'base': + # TODO: we can use more efficient residue reduction from ratint() + if not fd.is_sqf or fa.degree() >= fd.degree(): + # f is the logarithmic derivative in the base case if and only if + # f = fa/fd, fd is square-free, deg(fa) < deg(fd), and + # gcd(fa, fd) == 1. The last condition is handled by cancel() above. + return None + # Note: if residueterms = [], returns (1, 1) + # f had better be 0 in that case. + n = S.One*reduce(ilcm, [i.as_numer_denom()[1] for _, i in residueterms], 1) + u = Mul(*[Pow(i, j*n) for i, j in residueterms]) + return (n, u) + + elif case == 'tan': + raise NotImplementedError("The hypertangent case is " + "not yet implemented for is_log_deriv_k_t_radical_in_field()") + + elif case in ('other_linear', 'other_nonlinear'): + # XXX: If these are supported by the structure theorems, change to NotImplementedError. + raise ValueError("The %s case is not supported in this function." % case) + + else: + raise ValueError("case must be one of {'primitive', 'exp', 'tan', " + "'base', 'auto'}, not %s" % case) + + common_denom = S.One*reduce(ilcm, [i.as_numer_denom()[1] for i in [j for _, j in + residueterms]] + [n], 1) + residueterms = [(i, j*common_denom) for i, j in residueterms] + m = common_denom//n + if common_denom != n*m: # Verify exact division + raise ValueError("Inexact division") + u = cancel(u**m*Mul(*[Pow(i, j) for i, j in residueterms])) + + return (common_denom, u) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/quadrature.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/quadrature.py new file mode 100644 index 0000000000000000000000000000000000000000..b518bd427dc9980d6a941d2e1ef4d139c5f0f5f9 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/quadrature.py @@ -0,0 +1,617 @@ +from sympy.core import S, Dummy, pi +from sympy.functions.combinatorial.factorials import factorial +from sympy.functions.elementary.trigonometric import sin, cos +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.special.gamma_functions import gamma +from sympy.polys.orthopolys import (legendre_poly, laguerre_poly, + hermite_poly, jacobi_poly) +from sympy.polys.rootoftools import RootOf + + +def gauss_legendre(n, n_digits): + r""" + Computes the Gauss-Legendre quadrature [1]_ points and weights. + + Explanation + =========== + + The Gauss-Legendre quadrature approximates the integral: + + .. math:: + \int_{-1}^1 f(x)\,dx \approx \sum_{i=1}^n w_i f(x_i) + + The nodes `x_i` of an order `n` quadrature rule are the roots of `P_n` + and the weights `w_i` are given by: + + .. math:: + w_i = \frac{2}{\left(1-x_i^2\right) \left(P'_n(x_i)\right)^2} + + Parameters + ========== + + n : + The order of quadrature. + n_digits : + Number of significant digits of the points and weights to return. + + Returns + ======= + + (x, w) : the ``x`` and ``w`` are lists of points and weights as Floats. + The points `x_i` and weights `w_i` are returned as ``(x, w)`` + tuple of lists. + + Examples + ======== + + >>> from sympy.integrals.quadrature import gauss_legendre + >>> x, w = gauss_legendre(3, 5) + >>> x + [-0.7746, 0, 0.7746] + >>> w + [0.55556, 0.88889, 0.55556] + >>> x, w = gauss_legendre(4, 5) + >>> x + [-0.86114, -0.33998, 0.33998, 0.86114] + >>> w + [0.34785, 0.65215, 0.65215, 0.34785] + + See Also + ======== + + gauss_laguerre, gauss_gen_laguerre, gauss_hermite, gauss_chebyshev_t, gauss_chebyshev_u, gauss_jacobi, gauss_lobatto + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gaussian_quadrature + .. [2] https://people.sc.fsu.edu/~jburkardt/cpp_src/legendre_rule/legendre_rule.html + """ + x = Dummy("x") + p = legendre_poly(n, x, polys=True) + pd = p.diff(x) + xi = [] + w = [] + for r in p.real_roots(): + if isinstance(r, RootOf): + r = r.eval_rational(S.One/10**(n_digits+2)) + xi.append(r.n(n_digits)) + w.append((2/((1-r**2) * pd.subs(x, r)**2)).n(n_digits)) + return xi, w + + +def gauss_laguerre(n, n_digits): + r""" + Computes the Gauss-Laguerre quadrature [1]_ points and weights. + + Explanation + =========== + + The Gauss-Laguerre quadrature approximates the integral: + + .. math:: + \int_0^{\infty} e^{-x} f(x)\,dx \approx \sum_{i=1}^n w_i f(x_i) + + + The nodes `x_i` of an order `n` quadrature rule are the roots of `L_n` + and the weights `w_i` are given by: + + .. math:: + w_i = \frac{x_i}{(n+1)^2 \left(L_{n+1}(x_i)\right)^2} + + Parameters + ========== + + n : + The order of quadrature. + n_digits : + Number of significant digits of the points and weights to return. + + Returns + ======= + + (x, w) : The ``x`` and ``w`` are lists of points and weights as Floats. + The points `x_i` and weights `w_i` are returned as ``(x, w)`` + tuple of lists. + + Examples + ======== + + >>> from sympy.integrals.quadrature import gauss_laguerre + >>> x, w = gauss_laguerre(3, 5) + >>> x + [0.41577, 2.2943, 6.2899] + >>> w + [0.71109, 0.27852, 0.010389] + >>> x, w = gauss_laguerre(6, 5) + >>> x + [0.22285, 1.1889, 2.9927, 5.7751, 9.8375, 15.983] + >>> w + [0.45896, 0.417, 0.11337, 0.010399, 0.00026102, 8.9855e-7] + + See Also + ======== + + gauss_legendre, gauss_gen_laguerre, gauss_hermite, gauss_chebyshev_t, gauss_chebyshev_u, gauss_jacobi, gauss_lobatto + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gauss%E2%80%93Laguerre_quadrature + .. [2] https://people.sc.fsu.edu/~jburkardt/cpp_src/laguerre_rule/laguerre_rule.html + """ + x = Dummy("x") + p = laguerre_poly(n, x, polys=True) + p1 = laguerre_poly(n+1, x, polys=True) + xi = [] + w = [] + for r in p.real_roots(): + if isinstance(r, RootOf): + r = r.eval_rational(S.One/10**(n_digits+2)) + xi.append(r.n(n_digits)) + w.append((r/((n+1)**2 * p1.subs(x, r)**2)).n(n_digits)) + return xi, w + + +def gauss_hermite(n, n_digits): + r""" + Computes the Gauss-Hermite quadrature [1]_ points and weights. + + Explanation + =========== + + The Gauss-Hermite quadrature approximates the integral: + + .. math:: + \int_{-\infty}^{\infty} e^{-x^2} f(x)\,dx \approx + \sum_{i=1}^n w_i f(x_i) + + The nodes `x_i` of an order `n` quadrature rule are the roots of `H_n` + and the weights `w_i` are given by: + + .. math:: + w_i = \frac{2^{n-1} n! \sqrt{\pi}}{n^2 \left(H_{n-1}(x_i)\right)^2} + + Parameters + ========== + + n : + The order of quadrature. + n_digits : + Number of significant digits of the points and weights to return. + + Returns + ======= + + (x, w) : The ``x`` and ``w`` are lists of points and weights as Floats. + The points `x_i` and weights `w_i` are returned as ``(x, w)`` + tuple of lists. + + Examples + ======== + + >>> from sympy.integrals.quadrature import gauss_hermite + >>> x, w = gauss_hermite(3, 5) + >>> x + [-1.2247, 0, 1.2247] + >>> w + [0.29541, 1.1816, 0.29541] + + >>> x, w = gauss_hermite(6, 5) + >>> x + [-2.3506, -1.3358, -0.43608, 0.43608, 1.3358, 2.3506] + >>> w + [0.00453, 0.15707, 0.72463, 0.72463, 0.15707, 0.00453] + + See Also + ======== + + gauss_legendre, gauss_laguerre, gauss_gen_laguerre, gauss_chebyshev_t, gauss_chebyshev_u, gauss_jacobi, gauss_lobatto + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gauss-Hermite_Quadrature + .. [2] https://people.sc.fsu.edu/~jburkardt/cpp_src/hermite_rule/hermite_rule.html + .. [3] https://people.sc.fsu.edu/~jburkardt/cpp_src/gen_hermite_rule/gen_hermite_rule.html + """ + x = Dummy("x") + p = hermite_poly(n, x, polys=True) + p1 = hermite_poly(n-1, x, polys=True) + xi = [] + w = [] + for r in p.real_roots(): + if isinstance(r, RootOf): + r = r.eval_rational(S.One/10**(n_digits+2)) + xi.append(r.n(n_digits)) + w.append(((2**(n-1) * factorial(n) * sqrt(pi)) / + (n**2 * p1.subs(x, r)**2)).n(n_digits)) + return xi, w + + +def gauss_gen_laguerre(n, alpha, n_digits): + r""" + Computes the generalized Gauss-Laguerre quadrature [1]_ points and weights. + + Explanation + =========== + + The generalized Gauss-Laguerre quadrature approximates the integral: + + .. math:: + \int_{0}^\infty x^{\alpha} e^{-x} f(x)\,dx \approx + \sum_{i=1}^n w_i f(x_i) + + The nodes `x_i` of an order `n` quadrature rule are the roots of + `L^{\alpha}_n` and the weights `w_i` are given by: + + .. math:: + w_i = \frac{\Gamma(\alpha+n)} + {n \Gamma(n) L^{\alpha}_{n-1}(x_i) L^{\alpha+1}_{n-1}(x_i)} + + Parameters + ========== + + n : + The order of quadrature. + + alpha : + The exponent of the singularity, `\alpha > -1`. + + n_digits : + Number of significant digits of the points and weights to return. + + Returns + ======= + + (x, w) : the ``x`` and ``w`` are lists of points and weights as Floats. + The points `x_i` and weights `w_i` are returned as ``(x, w)`` + tuple of lists. + + Examples + ======== + + >>> from sympy import S + >>> from sympy.integrals.quadrature import gauss_gen_laguerre + >>> x, w = gauss_gen_laguerre(3, -S.Half, 5) + >>> x + [0.19016, 1.7845, 5.5253] + >>> w + [1.4493, 0.31413, 0.00906] + + >>> x, w = gauss_gen_laguerre(4, 3*S.Half, 5) + >>> x + [0.97851, 2.9904, 6.3193, 11.712] + >>> w + [0.53087, 0.67721, 0.11895, 0.0023152] + + See Also + ======== + + gauss_legendre, gauss_laguerre, gauss_hermite, gauss_chebyshev_t, gauss_chebyshev_u, gauss_jacobi, gauss_lobatto + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gauss%E2%80%93Laguerre_quadrature + .. [2] https://people.sc.fsu.edu/~jburkardt/cpp_src/gen_laguerre_rule/gen_laguerre_rule.html + """ + x = Dummy("x") + p = laguerre_poly(n, x, alpha=alpha, polys=True) + p1 = laguerre_poly(n-1, x, alpha=alpha, polys=True) + p2 = laguerre_poly(n-1, x, alpha=alpha+1, polys=True) + xi = [] + w = [] + for r in p.real_roots(): + if isinstance(r, RootOf): + r = r.eval_rational(S.One/10**(n_digits+2)) + xi.append(r.n(n_digits)) + w.append((gamma(alpha+n) / + (n*gamma(n)*p1.subs(x, r)*p2.subs(x, r))).n(n_digits)) + return xi, w + + +def gauss_chebyshev_t(n, n_digits): + r""" + Computes the Gauss-Chebyshev quadrature [1]_ points and weights of + the first kind. + + Explanation + =========== + + The Gauss-Chebyshev quadrature of the first kind approximates the integral: + + .. math:: + \int_{-1}^{1} \frac{1}{\sqrt{1-x^2}} f(x)\,dx \approx + \sum_{i=1}^n w_i f(x_i) + + The nodes `x_i` of an order `n` quadrature rule are the roots of `T_n` + and the weights `w_i` are given by: + + .. math:: + w_i = \frac{\pi}{n} + + Parameters + ========== + + n : + The order of quadrature. + + n_digits : + Number of significant digits of the points and weights to return. + + Returns + ======= + + (x, w) : the ``x`` and ``w`` are lists of points and weights as Floats. + The points `x_i` and weights `w_i` are returned as ``(x, w)`` + tuple of lists. + + Examples + ======== + + >>> from sympy.integrals.quadrature import gauss_chebyshev_t + >>> x, w = gauss_chebyshev_t(3, 5) + >>> x + [0.86602, 0, -0.86602] + >>> w + [1.0472, 1.0472, 1.0472] + + >>> x, w = gauss_chebyshev_t(6, 5) + >>> x + [0.96593, 0.70711, 0.25882, -0.25882, -0.70711, -0.96593] + >>> w + [0.5236, 0.5236, 0.5236, 0.5236, 0.5236, 0.5236] + + See Also + ======== + + gauss_legendre, gauss_laguerre, gauss_hermite, gauss_gen_laguerre, gauss_chebyshev_u, gauss_jacobi, gauss_lobatto + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Chebyshev%E2%80%93Gauss_quadrature + .. [2] https://people.sc.fsu.edu/~jburkardt/cpp_src/chebyshev1_rule/chebyshev1_rule.html + """ + xi = [] + w = [] + for i in range(1, n+1): + xi.append((cos((2*i-S.One)/(2*n)*S.Pi)).n(n_digits)) + w.append((S.Pi/n).n(n_digits)) + return xi, w + + +def gauss_chebyshev_u(n, n_digits): + r""" + Computes the Gauss-Chebyshev quadrature [1]_ points and weights of + the second kind. + + Explanation + =========== + + The Gauss-Chebyshev quadrature of the second kind approximates the + integral: + + .. math:: + \int_{-1}^{1} \sqrt{1-x^2} f(x)\,dx \approx \sum_{i=1}^n w_i f(x_i) + + The nodes `x_i` of an order `n` quadrature rule are the roots of `U_n` + and the weights `w_i` are given by: + + .. math:: + w_i = \frac{\pi}{n+1} \sin^2 \left(\frac{i}{n+1}\pi\right) + + Parameters + ========== + + n : the order of quadrature + + n_digits : number of significant digits of the points and weights to return + + Returns + ======= + + (x, w) : the ``x`` and ``w`` are lists of points and weights as Floats. + The points `x_i` and weights `w_i` are returned as ``(x, w)`` + tuple of lists. + + Examples + ======== + + >>> from sympy.integrals.quadrature import gauss_chebyshev_u + >>> x, w = gauss_chebyshev_u(3, 5) + >>> x + [0.70711, 0, -0.70711] + >>> w + [0.3927, 0.7854, 0.3927] + + >>> x, w = gauss_chebyshev_u(6, 5) + >>> x + [0.90097, 0.62349, 0.22252, -0.22252, -0.62349, -0.90097] + >>> w + [0.084489, 0.27433, 0.42658, 0.42658, 0.27433, 0.084489] + + See Also + ======== + + gauss_legendre, gauss_laguerre, gauss_hermite, gauss_gen_laguerre, gauss_chebyshev_t, gauss_jacobi, gauss_lobatto + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Chebyshev%E2%80%93Gauss_quadrature + .. [2] https://people.sc.fsu.edu/~jburkardt/cpp_src/chebyshev2_rule/chebyshev2_rule.html + """ + xi = [] + w = [] + for i in range(1, n+1): + xi.append((cos(i/(n+S.One)*S.Pi)).n(n_digits)) + w.append((S.Pi/(n+S.One)*sin(i*S.Pi/(n+S.One))**2).n(n_digits)) + return xi, w + + +def gauss_jacobi(n, alpha, beta, n_digits): + r""" + Computes the Gauss-Jacobi quadrature [1]_ points and weights. + + Explanation + =========== + + The Gauss-Jacobi quadrature of the first kind approximates the integral: + + .. math:: + \int_{-1}^1 (1-x)^\alpha (1+x)^\beta f(x)\,dx \approx + \sum_{i=1}^n w_i f(x_i) + + The nodes `x_i` of an order `n` quadrature rule are the roots of + `P^{(\alpha,\beta)}_n` and the weights `w_i` are given by: + + .. math:: + w_i = -\frac{2n+\alpha+\beta+2}{n+\alpha+\beta+1} + \frac{\Gamma(n+\alpha+1)\Gamma(n+\beta+1)} + {\Gamma(n+\alpha+\beta+1)(n+1)!} + \frac{2^{\alpha+\beta}}{P'_n(x_i) + P^{(\alpha,\beta)}_{n+1}(x_i)} + + Parameters + ========== + + n : the order of quadrature + + alpha : the first parameter of the Jacobi Polynomial, `\alpha > -1` + + beta : the second parameter of the Jacobi Polynomial, `\beta > -1` + + n_digits : number of significant digits of the points and weights to return + + Returns + ======= + + (x, w) : the ``x`` and ``w`` are lists of points and weights as Floats. + The points `x_i` and weights `w_i` are returned as ``(x, w)`` + tuple of lists. + + Examples + ======== + + >>> from sympy import S + >>> from sympy.integrals.quadrature import gauss_jacobi + >>> x, w = gauss_jacobi(3, S.Half, -S.Half, 5) + >>> x + [-0.90097, -0.22252, 0.62349] + >>> w + [1.7063, 1.0973, 0.33795] + + >>> x, w = gauss_jacobi(6, 1, 1, 5) + >>> x + [-0.87174, -0.5917, -0.2093, 0.2093, 0.5917, 0.87174] + >>> w + [0.050584, 0.22169, 0.39439, 0.39439, 0.22169, 0.050584] + + See Also + ======== + + gauss_legendre, gauss_laguerre, gauss_hermite, gauss_gen_laguerre, + gauss_chebyshev_t, gauss_chebyshev_u, gauss_lobatto + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gauss%E2%80%93Jacobi_quadrature + .. [2] https://people.sc.fsu.edu/~jburkardt/cpp_src/jacobi_rule/jacobi_rule.html + .. [3] https://people.sc.fsu.edu/~jburkardt/cpp_src/gegenbauer_rule/gegenbauer_rule.html + """ + x = Dummy("x") + p = jacobi_poly(n, alpha, beta, x, polys=True) + pd = p.diff(x) + pn = jacobi_poly(n+1, alpha, beta, x, polys=True) + xi = [] + w = [] + for r in p.real_roots(): + if isinstance(r, RootOf): + r = r.eval_rational(S.One/10**(n_digits+2)) + xi.append(r.n(n_digits)) + w.append(( + - (2*n+alpha+beta+2) / (n+alpha+beta+S.One) * + (gamma(n+alpha+1)*gamma(n+beta+1)) / + (gamma(n+alpha+beta+S.One)*gamma(n+2)) * + 2**(alpha+beta) / (pd.subs(x, r) * pn.subs(x, r))).n(n_digits)) + return xi, w + + +def gauss_lobatto(n, n_digits): + r""" + Computes the Gauss-Lobatto quadrature [1]_ points and weights. + + Explanation + =========== + + The Gauss-Lobatto quadrature approximates the integral: + + .. math:: + \int_{-1}^1 f(x)\,dx \approx \sum_{i=1}^n w_i f(x_i) + + The nodes `x_i` of an order `n` quadrature rule are the roots of `P'_(n-1)` + and the weights `w_i` are given by: + + .. math:: + &w_i = \frac{2}{n(n-1) \left[P_{n-1}(x_i)\right]^2},\quad x\neq\pm 1\\ + &w_i = \frac{2}{n(n-1)},\quad x=\pm 1 + + Parameters + ========== + + n : the order of quadrature + + n_digits : number of significant digits of the points and weights to return + + Returns + ======= + + (x, w) : the ``x`` and ``w`` are lists of points and weights as Floats. + The points `x_i` and weights `w_i` are returned as ``(x, w)`` + tuple of lists. + + Examples + ======== + + >>> from sympy.integrals.quadrature import gauss_lobatto + >>> x, w = gauss_lobatto(3, 5) + >>> x + [-1, 0, 1] + >>> w + [0.33333, 1.3333, 0.33333] + >>> x, w = gauss_lobatto(4, 5) + >>> x + [-1, -0.44721, 0.44721, 1] + >>> w + [0.16667, 0.83333, 0.83333, 0.16667] + + See Also + ======== + + gauss_legendre,gauss_laguerre, gauss_gen_laguerre, gauss_hermite, gauss_chebyshev_t, gauss_chebyshev_u, gauss_jacobi + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gaussian_quadrature#Gauss.E2.80.93Lobatto_rules + .. [2] https://web.archive.org/web/20200118141346/http://people.math.sfu.ca/~cbm/aands/page_888.htm + """ + x = Dummy("x") + p = legendre_poly(n-1, x, polys=True) + pd = p.diff(x) + xi = [] + w = [] + for r in pd.real_roots(): + if isinstance(r, RootOf): + r = r.eval_rational(S.One/10**(n_digits+2)) + xi.append(r.n(n_digits)) + w.append((2/(n*(n-1) * p.subs(x, r)**2)).n(n_digits)) + + xi.insert(0, -1) + xi.append(1) + w.insert(0, (S(2)/(n*(n-1))).n(n_digits)) + w.append((S(2)/(n*(n-1))).n(n_digits)) + return xi, w diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/rationaltools.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/rationaltools.py new file mode 100644 index 0000000000000000000000000000000000000000..e95ff5da2e9d1be6f07d8fe6e9c572f692e92efb --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/rationaltools.py @@ -0,0 +1,445 @@ +"""This module implements tools for integrating rational functions. """ + +from sympy.core.function import Lambda +from sympy.core.numbers import I +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, Symbol, symbols) +from sympy.functions.elementary.exponential import log +from sympy.functions.elementary.trigonometric import atan +from sympy.polys.polyerrors import DomainError +from sympy.polys.polyroots import roots +from sympy.polys.polytools import cancel +from sympy.polys.rootoftools import RootSum +from sympy.polys import Poly, resultant, ZZ + + +def ratint(f, x, **flags): + """ + Performs indefinite integration of rational functions. + + Explanation + =========== + + Given a field :math:`K` and a rational function :math:`f = p/q`, + where :math:`p` and :math:`q` are polynomials in :math:`K[x]`, + returns a function :math:`g` such that :math:`f = g'`. + + Examples + ======== + + >>> from sympy.integrals.rationaltools import ratint + >>> from sympy.abc import x + + >>> ratint(36/(x**5 - 2*x**4 - 2*x**3 + 4*x**2 + x - 2), x) + (12*x + 6)/(x**2 - 1) + 4*log(x - 2) - 4*log(x + 1) + + References + ========== + + .. [1] M. Bronstein, Symbolic Integration I: Transcendental + Functions, Second Edition, Springer-Verlag, 2005, pp. 35-70 + + See Also + ======== + + sympy.integrals.integrals.Integral.doit + sympy.integrals.rationaltools.ratint_logpart + sympy.integrals.rationaltools.ratint_ratpart + + """ + if isinstance(f, tuple): + p, q = f + else: + p, q = f.as_numer_denom() + + p, q = Poly(p, x, composite=False, field=True), Poly(q, x, composite=False, field=True) + + coeff, p, q = p.cancel(q) + poly, p = p.div(q) + + result = poly.integrate(x).as_expr() + + if p.is_zero: + return coeff*result + + g, h = ratint_ratpart(p, q, x) + + P, Q = h.as_numer_denom() + + P = Poly(P, x) + Q = Poly(Q, x) + + q, r = P.div(Q) + + result += g + q.integrate(x).as_expr() + + if not r.is_zero: + symbol = flags.get('symbol', 't') + + if not isinstance(symbol, Symbol): + t = Dummy(symbol) + else: + t = symbol.as_dummy() + + L = ratint_logpart(r, Q, x, t) + + real = flags.get('real') + + if real is None: + if isinstance(f, tuple): + p, q = f + atoms = p.atoms() | q.atoms() + else: + atoms = f.atoms() + + for elt in atoms - {x}: + if not elt.is_extended_real: + real = False + break + else: + real = True + + eps = S.Zero + + if not real: + for h, q in L: + _, h = h.primitive() + eps += RootSum( + q, Lambda(t, t*log(h.as_expr())), quadratic=True) + else: + for h, q in L: + _, h = h.primitive() + R = log_to_real(h, q, x, t) + + if R is not None: + eps += R + else: + eps += RootSum( + q, Lambda(t, t*log(h.as_expr())), quadratic=True) + + result += eps + + return coeff*result + + +def ratint_ratpart(f, g, x): + """ + Horowitz-Ostrogradsky algorithm. + + Explanation + =========== + + Given a field K and polynomials f and g in K[x], such that f and g + are coprime and deg(f) < deg(g), returns fractions A and B in K(x), + such that f/g = A' + B and B has square-free denominator. + + Examples + ======== + + >>> from sympy.integrals.rationaltools import ratint_ratpart + >>> from sympy.abc import x, y + >>> from sympy import Poly + >>> ratint_ratpart(Poly(1, x, domain='ZZ'), + ... Poly(x + 1, x, domain='ZZ'), x) + (0, 1/(x + 1)) + >>> ratint_ratpart(Poly(1, x, domain='EX'), + ... Poly(x**2 + y**2, x, domain='EX'), x) + (0, 1/(x**2 + y**2)) + >>> ratint_ratpart(Poly(36, x, domain='ZZ'), + ... Poly(x**5 - 2*x**4 - 2*x**3 + 4*x**2 + x - 2, x, domain='ZZ'), x) + ((12*x + 6)/(x**2 - 1), 12/(x**2 - x - 2)) + + See Also + ======== + + ratint, ratint_logpart + """ + from sympy.solvers.solvers import solve + + f = Poly(f, x) + g = Poly(g, x) + + u, v, _ = g.cofactors(g.diff()) + + n = u.degree() + m = v.degree() + + A_coeffs = [ Dummy('a' + str(n - i)) for i in range(0, n) ] + B_coeffs = [ Dummy('b' + str(m - i)) for i in range(0, m) ] + + C_coeffs = A_coeffs + B_coeffs + + A = Poly(A_coeffs, x, domain=ZZ[C_coeffs]) + B = Poly(B_coeffs, x, domain=ZZ[C_coeffs]) + + H = f - A.diff()*v + A*(u.diff()*v).quo(u) - B*u + + result = solve(H.coeffs(), C_coeffs) + + A = A.as_expr().subs(result) + B = B.as_expr().subs(result) + + rat_part = cancel(A/u.as_expr(), x) + log_part = cancel(B/v.as_expr(), x) + + return rat_part, log_part + + +def ratint_logpart(f, g, x, t=None): + r""" + Lazard-Rioboo-Trager algorithm. + + Explanation + =========== + + Given a field K and polynomials f and g in K[x], such that f and g + are coprime, deg(f) < deg(g) and g is square-free, returns a list + of tuples (s_i, q_i) of polynomials, for i = 1..n, such that s_i + in K[t, x] and q_i in K[t], and:: + + ___ ___ + d f d \ ` \ ` + -- - = -- ) ) a log(s_i(a, x)) + dx g dx /__, /__, + i=1..n a | q_i(a) = 0 + + Examples + ======== + + >>> from sympy.integrals.rationaltools import ratint_logpart + >>> from sympy.abc import x + >>> from sympy import Poly + >>> ratint_logpart(Poly(1, x, domain='ZZ'), + ... Poly(x**2 + x + 1, x, domain='ZZ'), x) + [(Poly(x + 3*_t/2 + 1/2, x, domain='QQ[_t]'), + ...Poly(3*_t**2 + 1, _t, domain='ZZ'))] + >>> ratint_logpart(Poly(12, x, domain='ZZ'), + ... Poly(x**2 - x - 2, x, domain='ZZ'), x) + [(Poly(x - 3*_t/8 - 1/2, x, domain='QQ[_t]'), + ...Poly(-_t**2 + 16, _t, domain='ZZ'))] + + See Also + ======== + + ratint, ratint_ratpart + """ + f, g = Poly(f, x), Poly(g, x) + + t = t or Dummy('t') + a, b = g, f - g.diff()*Poly(t, x) + + res, R = resultant(a, b, includePRS=True) + res = Poly(res, t, composite=False) + + assert res, "BUG: resultant(%s, %s) cannot be zero" % (a, b) + + R_map, H = {}, [] + + for r in R: + R_map[r.degree()] = r + + def _include_sign(c, sqf): + if c.is_extended_real and (c < 0) == True: + h, k = sqf[0] + c_poly = c.as_poly(h.gens) + sqf[0] = h*c_poly, k + + C, res_sqf = res.sqf_list() + _include_sign(C, res_sqf) + + for q, i in res_sqf: + _, q = q.primitive() + + if g.degree() == i: + H.append((g, q)) + else: + h = R_map[i] + h_lc = Poly(h.LC(), t, field=True) + + c, h_lc_sqf = h_lc.sqf_list(all=True) + _include_sign(c, h_lc_sqf) + + for a, j in h_lc_sqf: + h = h.quo(Poly(a.gcd(q)**j, x)) + + inv, coeffs = h_lc.invert(q), [S.One] + + for coeff in h.coeffs()[1:]: + coeff = coeff.as_poly(inv.gens) + T = (inv*coeff).rem(q) + coeffs.append(T.as_expr()) + + h = Poly(dict(list(zip(h.monoms(), coeffs))), x) + + H.append((h, q)) + + return H + + +def log_to_atan(f, g): + """ + Convert complex logarithms to real arctangents. + + Explanation + =========== + + Given a real field K and polynomials f and g in K[x], with g != 0, + returns a sum h of arctangents of polynomials in K[x], such that: + + dh d f + I g + -- = -- I log( ------- ) + dx dx f - I g + + Examples + ======== + + >>> from sympy.integrals.rationaltools import log_to_atan + >>> from sympy.abc import x + >>> from sympy import Poly, sqrt, S + >>> log_to_atan(Poly(x, x, domain='ZZ'), Poly(1, x, domain='ZZ')) + 2*atan(x) + >>> log_to_atan(Poly(x + S(1)/2, x, domain='QQ'), + ... Poly(sqrt(3)/2, x, domain='EX')) + 2*atan(2*sqrt(3)*x/3 + sqrt(3)/3) + + See Also + ======== + + log_to_real + """ + if f.degree() < g.degree(): + f, g = -g, f + + f = f.to_field() + g = g.to_field() + + p, q = f.div(g) + + if q.is_zero: + return 2*atan(p.as_expr()) + else: + s, t, h = g.gcdex(-f) + u = (f*s + g*t).quo(h) + A = 2*atan(u.as_expr()) + + return A + log_to_atan(s, t) + + +def _get_real_roots(f, x): + """get real roots of f if possible""" + rs = roots(f, filter='R') + + try: + num_roots = f.count_roots() + except DomainError: + return rs + else: + if len(rs) == num_roots: + return rs + else: + return None + + +def log_to_real(h, q, x, t): + r""" + Convert complex logarithms to real functions. + + Explanation + =========== + + Given real field K and polynomials h in K[t,x] and q in K[t], + returns real function f such that: + ___ + df d \ ` + -- = -- ) a log(h(a, x)) + dx dx /__, + a | q(a) = 0 + + Examples + ======== + + >>> from sympy.integrals.rationaltools import log_to_real + >>> from sympy.abc import x, y + >>> from sympy import Poly, S + >>> log_to_real(Poly(x + 3*y/2 + S(1)/2, x, domain='QQ[y]'), + ... Poly(3*y**2 + 1, y, domain='ZZ'), x, y) + 2*sqrt(3)*atan(2*sqrt(3)*x/3 + sqrt(3)/3)/3 + >>> log_to_real(Poly(x**2 - 1, x, domain='ZZ'), + ... Poly(-2*y + 1, y, domain='ZZ'), x, y) + log(x**2 - 1)/2 + + See Also + ======== + + log_to_atan + """ + from sympy.simplify.radsimp import collect + u, v = symbols('u,v', cls=Dummy) + + H = h.as_expr().xreplace({t: u + I*v}).expand() + Q = q.as_expr().xreplace({t: u + I*v}).expand() + + H_map = collect(H, I, evaluate=False) + Q_map = collect(Q, I, evaluate=False) + + a, b = H_map.get(S.One, S.Zero), H_map.get(I, S.Zero) + c, d = Q_map.get(S.One, S.Zero), Q_map.get(I, S.Zero) + + R = Poly(resultant(c, d, v), u) + + R_u = _get_real_roots(R, u) + + if R_u is None: + return None + + result = S.Zero + + for r_u in R_u.keys(): + C = Poly(c.xreplace({u: r_u}), v) + if not C: + # t was split into real and imaginary parts + # and denom Q(u, v) = c + I*d. We just found + # that c(r_u) is 0 so the roots are in d + C = Poly(d.xreplace({u: r_u}), v) + # we were going to reject roots from C that + # did not set d to zero, but since we are now + # using C = d and c is already 0, there is + # nothing to check + d = S.Zero + + R_v = _get_real_roots(C, v) + + if R_v is None: + return None + + R_v_paired = [] # take one from each pair of conjugate roots + for r_v in R_v: + if r_v not in R_v_paired and -r_v not in R_v_paired: + if r_v.is_negative or r_v.could_extract_minus_sign(): + R_v_paired.append(-r_v) + elif not r_v.is_zero: + R_v_paired.append(r_v) + + for r_v in R_v_paired: + + D = d.xreplace({u: r_u, v: r_v}) + + if D.evalf(chop=True) != 0: + continue + + A = Poly(a.xreplace({u: r_u, v: r_v}), x) + B = Poly(b.xreplace({u: r_u, v: r_v}), x) + + AB = (A**2 + B**2).as_expr() + + result += r_u*log(AB) + r_v*log_to_atan(A, B) + + R_q = _get_real_roots(q, t) + + if R_q is None: + return None + + for r in R_q.keys(): + result += r*log(h.as_expr().subs(t, r)) + + return result diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/rde.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/rde.py new file mode 100644 index 0000000000000000000000000000000000000000..9fb14a1d14b743b1e0885bf25a0d4b409e8a610d --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/rde.py @@ -0,0 +1,800 @@ +""" +Algorithms for solving the Risch differential equation. + +Given a differential field K of characteristic 0 that is a simple +monomial extension of a base field k and f, g in K, the Risch +Differential Equation problem is to decide if there exist y in K such +that Dy + f*y == g and to find one if there are some. If t is a +monomial over k and the coefficients of f and g are in k(t), then y is +in k(t), and the outline of the algorithm here is given as: + +1. Compute the normal part n of the denominator of y. The problem is +then reduced to finding y' in k, where y == y'/n. +2. Compute the special part s of the denominator of y. The problem is +then reduced to finding y'' in k[t], where y == y''/(n*s) +3. Bound the degree of y''. +4. Reduce the equation Dy + f*y == g to a similar equation with f, g in +k[t]. +5. Find the solutions in k[t] of bounded degree of the reduced equation. + +See Chapter 6 of "Symbolic Integration I: Transcendental Functions" by +Manuel Bronstein. See also the docstring of risch.py. +""" + +from operator import mul +from functools import reduce + +from sympy.core import oo +from sympy.core.symbol import Dummy + +from sympy.polys import Poly, gcd, ZZ, cancel + +from sympy.functions.elementary.complexes import (im, re) +from sympy.functions.elementary.miscellaneous import sqrt + +from sympy.integrals.risch import (gcdex_diophantine, frac_in, derivation, + splitfactor, NonElementaryIntegralException, DecrementLevel, recognize_log_derivative) + +# TODO: Add messages to NonElementaryIntegralException errors + + +def order_at(a, p, t): + """ + Computes the order of a at p, with respect to t. + + Explanation + =========== + + For a, p in k[t], the order of a at p is defined as nu_p(a) = max({n + in Z+ such that p**n|a}), where a != 0. If a == 0, nu_p(a) = +oo. + + To compute the order at a rational function, a/b, use the fact that + nu_p(a/b) == nu_p(a) - nu_p(b). + """ + if a.is_zero: + return oo + if p == Poly(t, t): + return a.as_poly(t).ET()[0][0] + + # Uses binary search for calculating the power. power_list collects the tuples + # (p^k,k) where each k is some power of 2. After deciding the largest k + # such that k is power of 2 and p^k|a the loop iteratively calculates + # the actual power. + power_list = [] + p1 = p + r = a.rem(p1) + tracks_power = 1 + while r.is_zero: + power_list.append((p1,tracks_power)) + p1 = p1*p1 + tracks_power *= 2 + r = a.rem(p1) + n = 0 + product = Poly(1, t) + while len(power_list) != 0: + final = power_list.pop() + productf = product*final[0] + r = a.rem(productf) + if r.is_zero: + n += final[1] + product = productf + return n + + +def order_at_oo(a, d, t): + """ + Computes the order of a/d at oo (infinity), with respect to t. + + For f in k(t), the order or f at oo is defined as deg(d) - deg(a), where + f == a/d. + """ + if a.is_zero: + return oo + return d.degree(t) - a.degree(t) + + +def weak_normalizer(a, d, DE, z=None): + """ + Weak normalization. + + Explanation + =========== + + Given a derivation D on k[t] and f == a/d in k(t), return q in k[t] + such that f - Dq/q is weakly normalized with respect to t. + + f in k(t) is said to be "weakly normalized" with respect to t if + residue_p(f) is not a positive integer for any normal irreducible p + in k[t] such that f is in R_p (Definition 6.1.1). If f has an + elementary integral, this is equivalent to no logarithm of + integral(f) whose argument depends on t has a positive integer + coefficient, where the arguments of the logarithms not in k(t) are + in k[t]. + + Returns (q, f - Dq/q) + """ + z = z or Dummy('z') + dn, ds = splitfactor(d, DE) + + # Compute d1, where dn == d1*d2**2*...*dn**n is a square-free + # factorization of d. + g = gcd(dn, dn.diff(DE.t)) + d_sqf_part = dn.quo(g) + d1 = d_sqf_part.quo(gcd(d_sqf_part, g)) + + a1, b = gcdex_diophantine(d.quo(d1).as_poly(DE.t), d1.as_poly(DE.t), + a.as_poly(DE.t)) + r = (a - Poly(z, DE.t)*derivation(d1, DE)).as_poly(DE.t).resultant( + d1.as_poly(DE.t)) + r = Poly(r, z) + + if not r.expr.has(z): + return (Poly(1, DE.t), (a, d)) + + N = [i for i in r.real_roots() if i in ZZ and i > 0] + + q = reduce(mul, [gcd(a - Poly(n, DE.t)*derivation(d1, DE), d1) for n in N], + Poly(1, DE.t)) + + dq = derivation(q, DE) + sn = q*a - d*dq + sd = q*d + sn, sd = sn.cancel(sd, include=True) + + return (q, (sn, sd)) + + +def normal_denom(fa, fd, ga, gd, DE): + """ + Normal part of the denominator. + + Explanation + =========== + + Given a derivation D on k[t] and f, g in k(t) with f weakly + normalized with respect to t, either raise NonElementaryIntegralException, + in which case the equation Dy + f*y == g has no solution in k(t), or the + quadruplet (a, b, c, h) such that a, h in k[t], b, c in k, and for any + solution y in k(t) of Dy + f*y == g, q = y*h in k satisfies + a*Dq + b*q == c. + + This constitutes step 1 in the outline given in the rde.py docstring. + """ + dn, ds = splitfactor(fd, DE) + en, es = splitfactor(gd, DE) + + p = dn.gcd(en) + h = en.gcd(en.diff(DE.t)).quo(p.gcd(p.diff(DE.t))) + + a = dn*h + c = a*h + if c.div(en)[1]: + # en does not divide dn*h**2 + raise NonElementaryIntegralException + ca = c*ga + ca, cd = ca.cancel(gd, include=True) + + ba = a*fa - dn*derivation(h, DE)*fd + ba, bd = ba.cancel(fd, include=True) + + # (dn*h, dn*h*f - dn*Dh, dn*h**2*g, h) + return (a, (ba, bd), (ca, cd), h) + + +def special_denom(a, ba, bd, ca, cd, DE, case='auto'): + """ + Special part of the denominator. + + Explanation + =========== + + case is one of {'exp', 'tan', 'primitive'} for the hyperexponential, + hypertangent, and primitive cases, respectively. For the + hyperexponential (resp. hypertangent) case, given a derivation D on + k[t] and a in k[t], b, c, in k with Dt/t in k (resp. Dt/(t**2 + 1) in + k, sqrt(-1) not in k), a != 0, and gcd(a, t) == 1 (resp. + gcd(a, t**2 + 1) == 1), return the quadruplet (A, B, C, 1/h) such that + A, B, C, h in k[t] and for any solution q in k of a*Dq + b*q == c, + r = qh in k[t] satisfies A*Dr + B*r == C. + + For ``case == 'primitive'``, k == k[t], so it returns (a, b, c, 1) in + this case. + + This constitutes step 2 of the outline given in the rde.py docstring. + """ + # TODO: finish writing this and write tests + + if case == 'auto': + case = DE.case + + if case == 'exp': + p = Poly(DE.t, DE.t) + elif case == 'tan': + p = Poly(DE.t**2 + 1, DE.t) + elif case in ('primitive', 'base'): + B = ba.to_field().quo(bd) + C = ca.to_field().quo(cd) + return (a, B, C, Poly(1, DE.t)) + else: + raise ValueError("case must be one of {'exp', 'tan', 'primitive', " + "'base'}, not %s." % case) + + nb = order_at(ba, p, DE.t) - order_at(bd, p, DE.t) + nc = order_at(ca, p, DE.t) - order_at(cd, p, DE.t) + + n = min(0, nc - min(0, nb)) + if not nb: + # Possible cancellation. + from .prde import parametric_log_deriv + if case == 'exp': + dcoeff = DE.d.quo(Poly(DE.t, DE.t)) + with DecrementLevel(DE): # We are guaranteed to not have problems, + # because case != 'base'. + alphaa, alphad = frac_in(-ba.eval(0)/bd.eval(0)/a.eval(0), DE.t) + etaa, etad = frac_in(dcoeff, DE.t) + A = parametric_log_deriv(alphaa, alphad, etaa, etad, DE) + if A is not None: + Q, m, z = A + if Q == 1: + n = min(n, m) + + elif case == 'tan': + dcoeff = DE.d.quo(Poly(DE.t**2+1, DE.t)) + with DecrementLevel(DE): # We are guaranteed to not have problems, + # because case != 'base'. + alphaa, alphad = frac_in(im(-ba.eval(sqrt(-1))/bd.eval(sqrt(-1))/a.eval(sqrt(-1))), DE.t) + betaa, betad = frac_in(re(-ba.eval(sqrt(-1))/bd.eval(sqrt(-1))/a.eval(sqrt(-1))), DE.t) + etaa, etad = frac_in(dcoeff, DE.t) + + if recognize_log_derivative(Poly(2, DE.t)*betaa, betad, DE): + A = parametric_log_deriv(alphaa*Poly(sqrt(-1), DE.t)*betad+alphad*betaa, alphad*betad, etaa, etad, DE) + if A is not None: + Q, m, z = A + if Q == 1: + n = min(n, m) + N = max(0, -nb, n - nc) + pN = p**N + pn = p**-n + + A = a*pN + B = ba*pN.quo(bd) + Poly(n, DE.t)*a*derivation(p, DE).quo(p)*pN + C = (ca*pN*pn).quo(cd) + h = pn + + # (a*p**N, (b + n*a*Dp/p)*p**N, c*p**(N - n), p**-n) + return (A, B, C, h) + + +def bound_degree(a, b, cQ, DE, case='auto', parametric=False): + """ + Bound on polynomial solutions. + + Explanation + =========== + + Given a derivation D on k[t] and ``a``, ``b``, ``c`` in k[t] with ``a != 0``, return + n in ZZ such that deg(q) <= n for any solution q in k[t] of + a*Dq + b*q == c, when parametric=False, or deg(q) <= n for any solution + c1, ..., cm in Const(k) and q in k[t] of a*Dq + b*q == Sum(ci*gi, (i, 1, m)) + when parametric=True. + + For ``parametric=False``, ``cQ`` is ``c``, a ``Poly``; for ``parametric=True``, ``cQ`` is Q == + [q1, ..., qm], a list of Polys. + + This constitutes step 3 of the outline given in the rde.py docstring. + """ + # TODO: finish writing this and write tests + + if case == 'auto': + case = DE.case + + da = a.degree(DE.t) + db = b.degree(DE.t) + + # The parametric and regular cases are identical, except for this part + if parametric: + dc = max(i.degree(DE.t) for i in cQ) + else: + dc = cQ.degree(DE.t) + + alpha = cancel(-b.as_poly(DE.t).LC().as_expr()/ + a.as_poly(DE.t).LC().as_expr()) + + if case == 'base': + n = max(0, dc - max(db, da - 1)) + if db == da - 1 and alpha.is_Integer: + n = max(0, alpha, dc - db) + + elif case == 'primitive': + if db > da: + n = max(0, dc - db) + else: + n = max(0, dc - da + 1) + + etaa, etad = frac_in(DE.d, DE.T[DE.level - 1]) + + t1 = DE.t + with DecrementLevel(DE): + alphaa, alphad = frac_in(alpha, DE.t) + if db == da - 1: + from .prde import limited_integrate + # if alpha == m*Dt + Dz for z in k and m in ZZ: + try: + (za, zd), m = limited_integrate(alphaa, alphad, [(etaa, etad)], + DE) + except NonElementaryIntegralException: + pass + else: + if len(m) != 1: + raise ValueError("Length of m should be 1") + n = max(n, m[0]) + + elif db == da: + # if alpha == Dz/z for z in k*: + # beta = -lc(a*Dz + b*z)/(z*lc(a)) + # if beta == m*Dt + Dw for w in k and m in ZZ: + # n = max(n, m) + from .prde import is_log_deriv_k_t_radical_in_field + A = is_log_deriv_k_t_radical_in_field(alphaa, alphad, DE) + if A is not None: + aa, z = A + if aa == 1: + beta = -(a*derivation(z, DE).as_poly(t1) + + b*z.as_poly(t1)).LC()/(z.as_expr()*a.LC()) + betaa, betad = frac_in(beta, DE.t) + from .prde import limited_integrate + try: + (za, zd), m = limited_integrate(betaa, betad, + [(etaa, etad)], DE) + except NonElementaryIntegralException: + pass + else: + if len(m) != 1: + raise ValueError("Length of m should be 1") + n = max(n, m[0].as_expr()) + + elif case == 'exp': + from .prde import parametric_log_deriv + + n = max(0, dc - max(db, da)) + if da == db: + etaa, etad = frac_in(DE.d.quo(Poly(DE.t, DE.t)), DE.T[DE.level - 1]) + with DecrementLevel(DE): + alphaa, alphad = frac_in(alpha, DE.t) + A = parametric_log_deriv(alphaa, alphad, etaa, etad, DE) + if A is not None: + # if alpha == m*Dt/t + Dz/z for z in k* and m in ZZ: + # n = max(n, m) + a, m, z = A + if a == 1: + n = max(n, m) + + elif case in ('tan', 'other_nonlinear'): + delta = DE.d.degree(DE.t) + lam = DE.d.LC() + alpha = cancel(alpha/lam) + n = max(0, dc - max(da + delta - 1, db)) + if db == da + delta - 1 and alpha.is_Integer: + n = max(0, alpha, dc - db) + + else: + raise ValueError("case must be one of {'exp', 'tan', 'primitive', " + "'other_nonlinear', 'base'}, not %s." % case) + + return n + + +def spde(a, b, c, n, DE): + """ + Rothstein's Special Polynomial Differential Equation algorithm. + + Explanation + =========== + + Given a derivation D on k[t], an integer n and ``a``,``b``,``c`` in k[t] with + ``a != 0``, either raise NonElementaryIntegralException, in which case the + equation a*Dq + b*q == c has no solution of degree at most ``n`` in + k[t], or return the tuple (B, C, m, alpha, beta) such that B, C, + alpha, beta in k[t], m in ZZ, and any solution q in k[t] of degree + at most n of a*Dq + b*q == c must be of the form + q == alpha*h + beta, where h in k[t], deg(h) <= m, and Dh + B*h == C. + + This constitutes step 4 of the outline given in the rde.py docstring. + """ + zero = Poly(0, DE.t) + + alpha = Poly(1, DE.t) + beta = Poly(0, DE.t) + + while True: + if c.is_zero: + return (zero, zero, 0, zero, beta) # -1 is more to the point + if (n < 0) is True: + raise NonElementaryIntegralException + + g = a.gcd(b) + if not c.rem(g).is_zero: # g does not divide c + raise NonElementaryIntegralException + + a, b, c = a.quo(g), b.quo(g), c.quo(g) + + if a.degree(DE.t) == 0: + b = b.to_field().quo(a) + c = c.to_field().quo(a) + return (b, c, n, alpha, beta) + + r, z = gcdex_diophantine(b, a, c) + b += derivation(a, DE) + c = z - derivation(r, DE) + n -= a.degree(DE.t) + + beta += alpha * r + alpha *= a + +def no_cancel_b_large(b, c, n, DE): + """ + Poly Risch Differential Equation - No cancellation: deg(b) large enough. + + Explanation + =========== + + Given a derivation D on k[t], ``n`` either an integer or +oo, and ``b``,``c`` + in k[t] with ``b != 0`` and either D == d/dt or + deg(b) > max(0, deg(D) - 1), either raise NonElementaryIntegralException, in + which case the equation ``Dq + b*q == c`` has no solution of degree at + most n in k[t], or a solution q in k[t] of this equation with + ``deg(q) < n``. + """ + q = Poly(0, DE.t) + + while not c.is_zero: + m = c.degree(DE.t) - b.degree(DE.t) + if not 0 <= m <= n: # n < 0 or m < 0 or m > n + raise NonElementaryIntegralException + + p = Poly(c.as_poly(DE.t).LC()/b.as_poly(DE.t).LC()*DE.t**m, DE.t, + expand=False) + q = q + p + n = m - 1 + c = c - derivation(p, DE) - b*p + + return q + + +def no_cancel_b_small(b, c, n, DE): + """ + Poly Risch Differential Equation - No cancellation: deg(b) small enough. + + Explanation + =========== + + Given a derivation D on k[t], ``n`` either an integer or +oo, and ``b``,``c`` + in k[t] with deg(b) < deg(D) - 1 and either D == d/dt or + deg(D) >= 2, either raise NonElementaryIntegralException, in which case the + equation Dq + b*q == c has no solution of degree at most n in k[t], + or a solution q in k[t] of this equation with deg(q) <= n, or the + tuple (h, b0, c0) such that h in k[t], b0, c0, in k, and for any + solution q in k[t] of degree at most n of Dq + bq == c, y == q - h + is a solution in k of Dy + b0*y == c0. + """ + q = Poly(0, DE.t) + + while not c.is_zero: + if n == 0: + m = 0 + else: + m = c.degree(DE.t) - DE.d.degree(DE.t) + 1 + + if not 0 <= m <= n: # n < 0 or m < 0 or m > n + raise NonElementaryIntegralException + + if m > 0: + p = Poly(c.as_poly(DE.t).LC()/(m*DE.d.as_poly(DE.t).LC())*DE.t**m, + DE.t, expand=False) + else: + if b.degree(DE.t) != c.degree(DE.t): + raise NonElementaryIntegralException + if b.degree(DE.t) == 0: + return (q, b.as_poly(DE.T[DE.level - 1]), + c.as_poly(DE.T[DE.level - 1])) + p = Poly(c.as_poly(DE.t).LC()/b.as_poly(DE.t).LC(), DE.t, + expand=False) + + q = q + p + n = m - 1 + c = c - derivation(p, DE) - b*p + + return q + + +# TODO: better name for this function +def no_cancel_equal(b, c, n, DE): + """ + Poly Risch Differential Equation - No cancellation: deg(b) == deg(D) - 1 + + Explanation + =========== + + Given a derivation D on k[t] with deg(D) >= 2, n either an integer + or +oo, and b, c in k[t] with deg(b) == deg(D) - 1, either raise + NonElementaryIntegralException, in which case the equation Dq + b*q == c has + no solution of degree at most n in k[t], or a solution q in k[t] of + this equation with deg(q) <= n, or the tuple (h, m, C) such that h + in k[t], m in ZZ, and C in k[t], and for any solution q in k[t] of + degree at most n of Dq + b*q == c, y == q - h is a solution in k[t] + of degree at most m of Dy + b*y == C. + """ + q = Poly(0, DE.t) + lc = cancel(-b.as_poly(DE.t).LC()/DE.d.as_poly(DE.t).LC()) + if lc.is_Integer and lc.is_positive: + M = lc + else: + M = -1 + + while not c.is_zero: + m = max(M, c.degree(DE.t) - DE.d.degree(DE.t) + 1) + + if not 0 <= m <= n: # n < 0 or m < 0 or m > n + raise NonElementaryIntegralException + + u = cancel(m*DE.d.as_poly(DE.t).LC() + b.as_poly(DE.t).LC()) + if u.is_zero: + return (q, m, c) + if m > 0: + p = Poly(c.as_poly(DE.t).LC()/u*DE.t**m, DE.t, expand=False) + else: + if c.degree(DE.t) != DE.d.degree(DE.t) - 1: + raise NonElementaryIntegralException + else: + p = c.as_poly(DE.t).LC()/b.as_poly(DE.t).LC() + + q = q + p + n = m - 1 + c = c - derivation(p, DE) - b*p + + return q + + +def cancel_primitive(b, c, n, DE): + """ + Poly Risch Differential Equation - Cancellation: Primitive case. + + Explanation + =========== + + Given a derivation D on k[t], n either an integer or +oo, ``b`` in k, and + ``c`` in k[t] with Dt in k and ``b != 0``, either raise + NonElementaryIntegralException, in which case the equation Dq + b*q == c + has no solution of degree at most n in k[t], or a solution q in k[t] of + this equation with deg(q) <= n. + """ + # Delayed imports + from .prde import is_log_deriv_k_t_radical_in_field + with DecrementLevel(DE): + ba, bd = frac_in(b, DE.t) + A = is_log_deriv_k_t_radical_in_field(ba, bd, DE) + if A is not None: + n, z = A + if n == 1: # b == Dz/z + raise NotImplementedError("is_deriv_in_field() is required to " + " solve this problem.") + # if z*c == Dp for p in k[t] and deg(p) <= n: + # return p/z + # else: + # raise NonElementaryIntegralException + + if c.is_zero: + return c # return 0 + + if n < c.degree(DE.t): + raise NonElementaryIntegralException + + q = Poly(0, DE.t) + while not c.is_zero: + m = c.degree(DE.t) + if n < m: + raise NonElementaryIntegralException + with DecrementLevel(DE): + a2a, a2d = frac_in(c.LC(), DE.t) + sa, sd = rischDE(ba, bd, a2a, a2d, DE) + stm = Poly(sa.as_expr()/sd.as_expr()*DE.t**m, DE.t, expand=False) + q += stm + n = m - 1 + c -= b*stm + derivation(stm, DE) + + return q + + +def cancel_exp(b, c, n, DE): + """ + Poly Risch Differential Equation - Cancellation: Hyperexponential case. + + Explanation + =========== + + Given a derivation D on k[t], n either an integer or +oo, ``b`` in k, and + ``c`` in k[t] with Dt/t in k and ``b != 0``, either raise + NonElementaryIntegralException, in which case the equation Dq + b*q == c + has no solution of degree at most n in k[t], or a solution q in k[t] of + this equation with deg(q) <= n. + """ + from .prde import parametric_log_deriv + eta = DE.d.quo(Poly(DE.t, DE.t)).as_expr() + + with DecrementLevel(DE): + etaa, etad = frac_in(eta, DE.t) + ba, bd = frac_in(b, DE.t) + A = parametric_log_deriv(ba, bd, etaa, etad, DE) + if A is not None: + a, m, z = A + if a == 1: + raise NotImplementedError("is_deriv_in_field() is required to " + "solve this problem.") + # if c*z*t**m == Dp for p in k and q = p/(z*t**m) in k[t] and + # deg(q) <= n: + # return q + # else: + # raise NonElementaryIntegralException + + if c.is_zero: + return c # return 0 + + if n < c.degree(DE.t): + raise NonElementaryIntegralException + + q = Poly(0, DE.t) + while not c.is_zero: + m = c.degree(DE.t) + if n < m: + raise NonElementaryIntegralException + # a1 = b + m*Dt/t + a1 = b.as_expr() + with DecrementLevel(DE): + # TODO: Write a dummy function that does this idiom + a1a, a1d = frac_in(a1, DE.t) + a1a = a1a*etad + etaa*a1d*Poly(m, DE.t) + a1d = a1d*etad + + a2a, a2d = frac_in(c.LC(), DE.t) + + sa, sd = rischDE(a1a, a1d, a2a, a2d, DE) + stm = Poly(sa.as_expr()/sd.as_expr()*DE.t**m, DE.t, expand=False) + q += stm + n = m - 1 + c -= b*stm + derivation(stm, DE) # deg(c) becomes smaller + return q + + +def solve_poly_rde(b, cQ, n, DE, parametric=False): + """ + Solve a Polynomial Risch Differential Equation with degree bound ``n``. + + This constitutes step 4 of the outline given in the rde.py docstring. + + For parametric=False, cQ is c, a Poly; for parametric=True, cQ is Q == + [q1, ..., qm], a list of Polys. + """ + # No cancellation + if not b.is_zero and (DE.case == 'base' or + b.degree(DE.t) > max(0, DE.d.degree(DE.t) - 1)): + + if parametric: + # Delayed imports + from .prde import prde_no_cancel_b_large + return prde_no_cancel_b_large(b, cQ, n, DE) + return no_cancel_b_large(b, cQ, n, DE) + + elif (b.is_zero or b.degree(DE.t) < DE.d.degree(DE.t) - 1) and \ + (DE.case == 'base' or DE.d.degree(DE.t) >= 2): + + if parametric: + from .prde import prde_no_cancel_b_small + return prde_no_cancel_b_small(b, cQ, n, DE) + + R = no_cancel_b_small(b, cQ, n, DE) + + if isinstance(R, Poly): + return R + else: + # XXX: Might k be a field? (pg. 209) + h, b0, c0 = R + with DecrementLevel(DE): + b0, c0 = b0.as_poly(DE.t), c0.as_poly(DE.t) + if b0 is None: # See above comment + raise ValueError("b0 should be a non-Null value") + if c0 is None: + raise ValueError("c0 should be a non-Null value") + y = solve_poly_rde(b0, c0, n, DE).as_poly(DE.t) + return h + y + + elif DE.d.degree(DE.t) >= 2 and b.degree(DE.t) == DE.d.degree(DE.t) - 1 and \ + n > -b.as_poly(DE.t).LC()/DE.d.as_poly(DE.t).LC(): + + # TODO: Is this check necessary, and if so, what should it do if it fails? + # b comes from the first element returned from spde() + if not b.as_poly(DE.t).LC().is_number: + raise TypeError("Result should be a number") + + if parametric: + raise NotImplementedError("prde_no_cancel_b_equal() is not yet " + "implemented.") + + R = no_cancel_equal(b, cQ, n, DE) + + if isinstance(R, Poly): + return R + else: + h, m, C = R + # XXX: Or should it be rischDE()? + y = solve_poly_rde(b, C, m, DE) + return h + y + + else: + # Cancellation + if b.is_zero: + raise NotImplementedError("Remaining cases for Poly (P)RDE are " + "not yet implemented (is_deriv_in_field() required).") + else: + if DE.case == 'exp': + if parametric: + raise NotImplementedError("Parametric RDE cancellation " + "hyperexponential case is not yet implemented.") + return cancel_exp(b, cQ, n, DE) + + elif DE.case == 'primitive': + if parametric: + raise NotImplementedError("Parametric RDE cancellation " + "primitive case is not yet implemented.") + return cancel_primitive(b, cQ, n, DE) + + else: + raise NotImplementedError("Other Poly (P)RDE cancellation " + "cases are not yet implemented (%s)." % DE.case) + + if parametric: + raise NotImplementedError("Remaining cases for Poly PRDE not yet " + "implemented.") + raise NotImplementedError("Remaining cases for Poly RDE not yet " + "implemented.") + + +def rischDE(fa, fd, ga, gd, DE): + """ + Solve a Risch Differential Equation: Dy + f*y == g. + + Explanation + =========== + + See the outline in the docstring of rde.py for more information + about the procedure used. Either raise NonElementaryIntegralException, in + which case there is no solution y in the given differential field, + or return y in k(t) satisfying Dy + f*y == g, or raise + NotImplementedError, in which case, the algorithms necessary to + solve the given Risch Differential Equation have not yet been + implemented. + """ + _, (fa, fd) = weak_normalizer(fa, fd, DE) + a, (ba, bd), (ca, cd), hn = normal_denom(fa, fd, ga, gd, DE) + A, B, C, hs = special_denom(a, ba, bd, ca, cd, DE) + try: + # Until this is fully implemented, use oo. Note that this will almost + # certainly cause non-termination in spde() (unless A == 1), and + # *might* lead to non-termination in the next step for a nonelementary + # integral (I don't know for certain yet). Fortunately, spde() is + # currently written recursively, so this will just give + # RuntimeError: maximum recursion depth exceeded. + n = bound_degree(A, B, C, DE) + except NotImplementedError: + # Useful for debugging: + # import warnings + # warnings.warn("rischDE: Proceeding with n = oo; may cause " + # "non-termination.") + n = oo + + B, C, m, alpha, beta = spde(A, B, C, n, DE) + if C.is_zero: + y = C + else: + y = solve_poly_rde(B, C, m, DE) + + return (alpha*y + beta, hn*hs) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/risch.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/risch.py new file mode 100644 index 0000000000000000000000000000000000000000..89e5f10bbb1d011d98a5884ce74ab25b615e1c51 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/risch.py @@ -0,0 +1,1851 @@ +""" +The Risch Algorithm for transcendental function integration. + +The core algorithms for the Risch algorithm are here. The subproblem +algorithms are in the rde.py and prde.py files for the Risch +Differential Equation solver and the parametric problems solvers, +respectively. All important information concerning the differential extension +for an integrand is stored in a DifferentialExtension object, which in the code +is usually called DE. Throughout the code and Inside the DifferentialExtension +object, the conventions/attribute names are that the base domain is QQ and each +differential extension is x, t0, t1, ..., tn-1 = DE.t. DE.x is the variable of +integration (Dx == 1), DE.D is a list of the derivatives of +x, t1, t2, ..., tn-1 = t, DE.T is the list [x, t1, t2, ..., tn-1], DE.t is the +outer-most variable of the differential extension at the given level (the level +can be adjusted using DE.increment_level() and DE.decrement_level()), +k is the field C(x, t0, ..., tn-2), where C is the constant field. The +numerator of a fraction is denoted by a and the denominator by +d. If the fraction is named f, fa == numer(f) and fd == denom(f). +Fractions are returned as tuples (fa, fd). DE.d and DE.t are used to +represent the topmost derivation and extension variable, respectively. +The docstring of a function signifies whether an argument is in k[t], in +which case it will just return a Poly in t, or in k(t), in which case it +will return the fraction (fa, fd). Other variable names probably come +from the names used in Bronstein's book. +""" +from types import GeneratorType +from functools import reduce + +from sympy.core.function import Lambda +from sympy.core.mul import Mul +from sympy.core.intfunc import ilcm +from sympy.core.numbers import I +from sympy.core.power import Pow +from sympy.core.relational import Ne +from sympy.core.singleton import S +from sympy.core.sorting import ordered, default_sort_key +from sympy.core.symbol import Dummy, Symbol +from sympy.functions.elementary.exponential import log, exp +from sympy.functions.elementary.hyperbolic import (cosh, coth, sinh, + tanh) +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import (atan, sin, cos, + tan, acot, cot, asin, acos) +from .integrals import integrate, Integral +from .heurisch import _symbols +from sympy.polys.polyerrors import PolynomialError +from sympy.polys.polytools import (real_roots, cancel, Poly, gcd, + reduced) +from sympy.polys.rootoftools import RootSum +from sympy.utilities.iterables import numbered_symbols + + +def integer_powers(exprs): + """ + Rewrites a list of expressions as integer multiples of each other. + + Explanation + =========== + + For example, if you have [x, x/2, x**2 + 1, 2*x/3], then you can rewrite + this as [(x/6) * 6, (x/6) * 3, (x**2 + 1) * 1, (x/6) * 4]. This is useful + in the Risch integration algorithm, where we must write exp(x) + exp(x/2) + as (exp(x/2))**2 + exp(x/2), but not as exp(x) + sqrt(exp(x)) (this is + because only the transcendental case is implemented and we therefore cannot + integrate algebraic extensions). The integer multiples returned by this + function for each term are the smallest possible (their content equals 1). + + Returns a list of tuples where the first element is the base term and the + second element is a list of `(item, factor)` terms, where `factor` is the + integer multiplicative factor that must multiply the base term to obtain + the original item. + + The easiest way to understand this is to look at an example: + + >>> from sympy.abc import x + >>> from sympy.integrals.risch import integer_powers + >>> integer_powers([x, x/2, x**2 + 1, 2*x/3]) + [(x/6, [(x, 6), (x/2, 3), (2*x/3, 4)]), (x**2 + 1, [(x**2 + 1, 1)])] + + We can see how this relates to the example at the beginning of the + docstring. It chose x/6 as the first base term. Then, x can be written as + (x/2) * 2, so we get (0, 2), and so on. Now only element (x**2 + 1) + remains, and there are no other terms that can be written as a rational + multiple of that, so we get that it can be written as (x**2 + 1) * 1. + + """ + # Here is the strategy: + + # First, go through each term and determine if it can be rewritten as a + # rational multiple of any of the terms gathered so far. + # cancel(a/b).is_Rational is sufficient for this. If it is a multiple, we + # add its multiple to the dictionary. + + terms = {} + for term in exprs: + for trm, trm_list in terms.items(): + a = cancel(term/trm) + if a.is_Rational: + trm_list.append((term, a)) + break + else: + terms[term] = [(term, S.One)] + + # After we have done this, we have all the like terms together, so we just + # need to find a common denominator so that we can get the base term and + # integer multiples such that each term can be written as an integer + # multiple of the base term, and the content of the integers is 1. + + newterms = {} + for term, term_list in terms.items(): + common_denom = reduce(ilcm, [i.as_numer_denom()[1] for _, i in + term_list]) + newterm = term/common_denom + newmults = [(i, j*common_denom) for i, j in term_list] + newterms[newterm] = newmults + + return sorted(iter(newterms.items()), key=lambda item: item[0].sort_key()) + + +class DifferentialExtension: + """ + A container for all the information relating to a differential extension. + + Explanation + =========== + + The attributes of this object are (see also the docstring of __init__): + + - f: The original (Expr) integrand. + - x: The variable of integration. + - T: List of variables in the extension. + - D: List of derivations in the extension; corresponds to the elements of T. + - fa: Poly of the numerator of the integrand. + - fd: Poly of the denominator of the integrand. + - Tfuncs: Lambda() representations of each element of T (except for x). + For back-substitution after integration. + - backsubs: A (possibly empty) list of further substitutions to be made on + the final integral to make it look more like the integrand. + - exts: + - extargs: + - cases: List of string representations of the cases of T. + - t: The top level extension variable, as defined by the current level + (see level below). + - d: The top level extension derivation, as defined by the current + derivation (see level below). + - case: The string representation of the case of self.d. + (Note that self.T and self.D will always contain the complete extension, + regardless of the level. Therefore, you should ALWAYS use DE.t and DE.d + instead of DE.T[-1] and DE.D[-1]. If you want to have a list of the + derivations or variables only up to the current level, use + DE.D[:len(DE.D) + DE.level + 1] and DE.T[:len(DE.T) + DE.level + 1]. Note + that, in particular, the derivation() function does this.) + + The following are also attributes, but will probably not be useful other + than in internal use: + - newf: Expr form of fa/fd. + - level: The number (between -1 and -len(self.T)) such that + self.T[self.level] == self.t and self.D[self.level] == self.d. + Use the methods self.increment_level() and self.decrement_level() to change + the current level. + """ + # __slots__ is defined mainly so we can iterate over all the attributes + # of the class easily (the memory use doesn't matter too much, since we + # only create one DifferentialExtension per integration). Also, it's nice + # to have a safeguard when debugging. + __slots__ = ('f', 'x', 'T', 'D', 'fa', 'fd', 'Tfuncs', 'backsubs', + 'exts', 'extargs', 'cases', 'case', 't', 'd', 'newf', 'level', + 'ts', 'dummy') + + def __init__(self, f=None, x=None, handle_first='log', dummy=False, extension=None, rewrite_complex=None): + """ + Tries to build a transcendental extension tower from ``f`` with respect to ``x``. + + Explanation + =========== + + If it is successful, creates a DifferentialExtension object with, among + others, the attributes fa, fd, D, T, Tfuncs, and backsubs such that + fa and fd are Polys in T[-1] with rational coefficients in T[:-1], + fa/fd == f, and D[i] is a Poly in T[i] with rational coefficients in + T[:i] representing the derivative of T[i] for each i from 1 to len(T). + Tfuncs is a list of Lambda objects for back replacing the functions + after integrating. Lambda() is only used (instead of lambda) to make + them easier to test and debug. Note that Tfuncs corresponds to the + elements of T, except for T[0] == x, but they should be back-substituted + in reverse order. backsubs is a (possibly empty) back-substitution list + that should be applied on the completed integral to make it look more + like the original integrand. + + If it is unsuccessful, it raises NotImplementedError. + + You can also create an object by manually setting the attributes as a + dictionary to the extension keyword argument. You must include at least + D. Warning, any attribute that is not given will be set to None. The + attributes T, t, d, cases, case, x, and level are set automatically and + do not need to be given. The functions in the Risch Algorithm will NOT + check to see if an attribute is None before using it. This also does not + check to see if the extension is valid (non-algebraic) or even if it is + self-consistent. Therefore, this should only be used for + testing/debugging purposes. + """ + # XXX: If you need to debug this function, set the break point here + + if extension: + if 'D' not in extension: + raise ValueError("At least the key D must be included with " + "the extension flag to DifferentialExtension.") + for attr in extension: + setattr(self, attr, extension[attr]) + + self._auto_attrs() + + return + elif f is None or x is None: + raise ValueError("Either both f and x or a manual extension must " + "be given.") + + if handle_first not in ('log', 'exp'): + raise ValueError("handle_first must be 'log' or 'exp', not %s." % + str(handle_first)) + + # f will be the original function, self.f might change if we reset + # (e.g., we pull out a constant from an exponential) + self.f = f + self.x = x + # setting the default value 'dummy' + self.dummy = dummy + self.reset() + exp_new_extension, log_new_extension = True, True + + # case of 'automatic' choosing + if rewrite_complex is None: + rewrite_complex = I in self.f.atoms() + + if rewrite_complex: + rewritables = { + (sin, cos, cot, tan, sinh, cosh, coth, tanh): exp, + (asin, acos, acot, atan): log, + } + # rewrite the trigonometric components + for candidates, rule in rewritables.items(): + self.newf = self.newf.rewrite(candidates, rule) + self.newf = cancel(self.newf) + else: + if any(i.has(x) for i in self.f.atoms(sin, cos, tan, atan, asin, acos)): + raise NotImplementedError("Trigonometric extensions are not " + "supported (yet!)") + + exps = set() + pows = set() + numpows = set() + sympows = set() + logs = set() + symlogs = set() + + while True: + if self.newf.is_rational_function(*self.T): + break + + if not exp_new_extension and not log_new_extension: + # We couldn't find a new extension on the last pass, so I guess + # we can't do it. + raise NotImplementedError("Couldn't find an elementary " + "transcendental extension for %s. Try using a " % str(f) + + "manual extension with the extension flag.") + + exps, pows, numpows, sympows, log_new_extension = \ + self._rewrite_exps_pows(exps, pows, numpows, sympows, log_new_extension) + + logs, symlogs = self._rewrite_logs(logs, symlogs) + + if handle_first == 'exp' or not log_new_extension: + exp_new_extension = self._exp_part(exps) + if exp_new_extension is None: + # reset and restart + self.f = self.newf + self.reset() + exp_new_extension = True + continue + + if handle_first == 'log' or not exp_new_extension: + log_new_extension = self._log_part(logs) + + self.fa, self.fd = frac_in(self.newf, self.t) + self._auto_attrs() + + return + + def __getattr__(self, attr): + # Avoid AttributeErrors when debugging + if attr not in self.__slots__: + raise AttributeError("%s has no attribute %s" % (repr(self), repr(attr))) + return None + + def _rewrite_exps_pows(self, exps, pows, numpows, + sympows, log_new_extension): + """ + Rewrite exps/pows for better processing. + """ + from .prde import is_deriv_k + + # Pre-preparsing. + ################# + # Get all exp arguments, so we can avoid ahead of time doing + # something like t1 = exp(x), t2 = exp(x/2) == sqrt(t1). + + # Things like sqrt(exp(x)) do not automatically simplify to + # exp(x/2), so they will be viewed as algebraic. The easiest way + # to handle this is to convert all instances of exp(a)**Rational + # to exp(Rational*a) before doing anything else. Note that the + # _exp_part code can generate terms of this form, so we do need to + # do this at each pass (or else modify it to not do that). + + ratpows = [i for i in self.newf.atoms(Pow) + if (isinstance(i.base, exp) and i.exp.is_Rational)] + + ratpows_repl = [ + (i, i.base.base**(i.exp*i.base.exp)) for i in ratpows] + self.backsubs += [(j, i) for i, j in ratpows_repl] + self.newf = self.newf.xreplace(dict(ratpows_repl)) + + # To make the process deterministic, the args are sorted + # so that functions with smaller op-counts are processed first. + # Ties are broken with the default_sort_key. + + # XXX Although the method is deterministic no additional work + # has been done to guarantee that the simplest solution is + # returned and that it would be affected be using different + # variables. Though it is possible that this is the case + # one should know that it has not been done intentionally, so + # further improvements may be possible. + + # TODO: This probably doesn't need to be completely recomputed at + # each pass. + exps = update_sets(exps, self.newf.atoms(exp), + lambda i: i.exp.is_rational_function(*self.T) and + i.exp.has(*self.T)) + pows = update_sets(pows, self.newf.atoms(Pow), + lambda i: i.exp.is_rational_function(*self.T) and + i.exp.has(*self.T)) + numpows = update_sets(numpows, set(pows), + lambda i: not i.base.has(*self.T)) + sympows = update_sets(sympows, set(pows) - set(numpows), + lambda i: i.base.is_rational_function(*self.T) and + not i.exp.is_Integer) + + # The easiest way to deal with non-base E powers is to convert them + # into base E, integrate, and then convert back. + for i in ordered(pows): + old = i + new = exp(i.exp*log(i.base)) + # If exp is ever changed to automatically reduce exp(x*log(2)) + # to 2**x, then this will break. The solution is to not change + # exp to do that :) + if i in sympows: + if i.exp.is_Rational: + raise NotImplementedError("Algebraic extensions are " + "not supported (%s)." % str(i)) + # We can add a**b only if log(a) in the extension, because + # a**b == exp(b*log(a)). + basea, based = frac_in(i.base, self.t) + A = is_deriv_k(basea, based, self) + if A is None: + # Nonelementary monomial (so far) + + # TODO: Would there ever be any benefit from just + # adding log(base) as a new monomial? + # ANSWER: Yes, otherwise we can't integrate x**x (or + # rather prove that it has no elementary integral) + # without first manually rewriting it as exp(x*log(x)) + self.newf = self.newf.xreplace({old: new}) + self.backsubs += [(new, old)] + log_new_extension = self._log_part([log(i.base)]) + exps = update_sets(exps, self.newf.atoms(exp), lambda i: + i.exp.is_rational_function(*self.T) and i.exp.has(*self.T)) + continue + ans, u, const = A + newterm = exp(i.exp*(log(const) + u)) + # Under the current implementation, exp kills terms + # only if they are of the form a*log(x), where a is a + # Number. This case should have already been killed by the + # above tests. Again, if this changes to kill more than + # that, this will break, which maybe is a sign that you + # shouldn't be changing that. Actually, if anything, this + # auto-simplification should be removed. See + # https://groups.google.com/group/sympy/browse_thread/thread/a61d48235f16867f + + self.newf = self.newf.xreplace({i: newterm}) + + elif i not in numpows: + continue + else: + # i in numpows + newterm = new + # TODO: Just put it in self.Tfuncs + self.backsubs.append((new, old)) + self.newf = self.newf.xreplace({old: newterm}) + exps.append(newterm) + + return exps, pows, numpows, sympows, log_new_extension + + def _rewrite_logs(self, logs, symlogs): + """ + Rewrite logs for better processing. + """ + atoms = self.newf.atoms(log) + logs = update_sets(logs, atoms, + lambda i: i.args[0].is_rational_function(*self.T) and + i.args[0].has(*self.T)) + symlogs = update_sets(symlogs, atoms, + lambda i: i.has(*self.T) and i.args[0].is_Pow and + i.args[0].base.is_rational_function(*self.T) and + not i.args[0].exp.is_Integer) + + # We can handle things like log(x**y) by converting it to y*log(x) + # This will fix not only symbolic exponents of the argument, but any + # non-Integer exponent, like log(sqrt(x)). The exponent can also + # depend on x, like log(x**x). + for i in ordered(symlogs): + # Unlike in the exponential case above, we do not ever + # potentially add new monomials (above we had to add log(a)). + # Therefore, there is no need to run any is_deriv functions + # here. Just convert log(a**b) to b*log(a) and let + # log_new_extension() handle it from there. + lbase = log(i.args[0].base) + logs.append(lbase) + new = i.args[0].exp*lbase + self.newf = self.newf.xreplace({i: new}) + self.backsubs.append((new, i)) + + # remove any duplicates + logs = sorted(set(logs), key=default_sort_key) + + return logs, symlogs + + def _auto_attrs(self): + """ + Set attributes that are generated automatically. + """ + if not self.T: + # i.e., when using the extension flag and T isn't given + self.T = [i.gen for i in self.D] + if not self.x: + self.x = self.T[0] + self.cases = [get_case(d, t) for d, t in zip(self.D, self.T)] + self.level = -1 + self.t = self.T[self.level] + self.d = self.D[self.level] + self.case = self.cases[self.level] + + def _exp_part(self, exps): + """ + Try to build an exponential extension. + + Returns + ======= + + Returns True if there was a new extension, False if there was no new + extension but it was able to rewrite the given exponentials in terms + of the existing extension, and None if the entire extension building + process should be restarted. If the process fails because there is no + way around an algebraic extension (e.g., exp(log(x)/2)), it will raise + NotImplementedError. + """ + from .prde import is_log_deriv_k_t_radical + new_extension = False + restart = False + expargs = [i.exp for i in exps] + ip = integer_powers(expargs) + for arg, others in ip: + # Minimize potential problems with algebraic substitution + others.sort(key=lambda i: i[1]) + + arga, argd = frac_in(arg, self.t) + A = is_log_deriv_k_t_radical(arga, argd, self) + + if A is not None: + ans, u, n, const = A + # if n is 1 or -1, it's algebraic, but we can handle it + if n == -1: + # This probably will never happen, because + # Rational.as_numer_denom() returns the negative term in + # the numerator. But in case that changes, reduce it to + # n == 1. + n = 1 + u **= -1 + const *= -1 + ans = [(i, -j) for i, j in ans] + + if n == 1: + # Example: exp(x + x**2) over QQ(x, exp(x), exp(x**2)) + self.newf = self.newf.xreplace({exp(arg): exp(const)*Mul(*[ + u**power for u, power in ans])}) + self.newf = self.newf.xreplace({exp(p*exparg): + exp(const*p) * Mul(*[u**power for u, power in ans]) + for exparg, p in others}) + # TODO: Add something to backsubs to put exp(const*p) + # back together. + + continue + + else: + # Bad news: we have an algebraic radical. But maybe we + # could still avoid it by choosing a different extension. + # For example, integer_powers() won't handle exp(x/2 + 1) + # over QQ(x, exp(x)), but if we pull out the exp(1), it + # will. Or maybe we have exp(x + x**2/2), over + # QQ(x, exp(x), exp(x**2)), which is exp(x)*sqrt(exp(x**2)), + # but if we use QQ(x, exp(x), exp(x**2/2)), then they will + # all work. + # + # So here is what we do: If there is a non-zero const, pull + # it out and retry. Also, if len(ans) > 1, then rewrite + # exp(arg) as the product of exponentials from ans, and + # retry that. If const == 0 and len(ans) == 1, then we + # assume that it would have been handled by either + # integer_powers() or n == 1 above if it could be handled, + # so we give up at that point. For example, you can never + # handle exp(log(x)/2) because it equals sqrt(x). + + if const or len(ans) > 1: + rad = Mul(*[term**(power/n) for term, power in ans]) + self.newf = self.newf.xreplace({exp(p*exparg): + exp(const*p)*rad for exparg, p in others}) + self.newf = self.newf.xreplace(dict(list(zip(reversed(self.T), + reversed([f(self.x) for f in self.Tfuncs]))))) + restart = True + break + else: + # TODO: give algebraic dependence in error string + raise NotImplementedError("Cannot integrate over " + "algebraic extensions.") + + else: + arga, argd = frac_in(arg, self.t) + darga = (argd*derivation(Poly(arga, self.t), self) - + arga*derivation(Poly(argd, self.t), self)) + dargd = argd**2 + darga, dargd = darga.cancel(dargd, include=True) + darg = darga.as_expr()/dargd.as_expr() + self.t = next(self.ts) + self.T.append(self.t) + self.extargs.append(arg) + self.exts.append('exp') + self.D.append(darg.as_poly(self.t, expand=False)*Poly(self.t, + self.t, expand=False)) + if self.dummy: + i = Dummy("i") + else: + i = Symbol('i') + self.Tfuncs += [Lambda(i, exp(arg.subs(self.x, i)))] + self.newf = self.newf.xreplace( + {exp(exparg): self.t**p for exparg, p in others}) + new_extension = True + + if restart: + return None + return new_extension + + def _log_part(self, logs): + """ + Try to build a logarithmic extension. + + Returns + ======= + + Returns True if there was a new extension and False if there was no new + extension but it was able to rewrite the given logarithms in terms + of the existing extension. Unlike with exponential extensions, there + is no way that a logarithm is not transcendental over and cannot be + rewritten in terms of an already existing extension in a non-algebraic + way, so this function does not ever return None or raise + NotImplementedError. + """ + from .prde import is_deriv_k + new_extension = False + logargs = [i.args[0] for i in logs] + for arg in ordered(logargs): + # The log case is easier, because whenever a logarithm is algebraic + # over the base field, it is of the form a1*t1 + ... an*tn + c, + # which is a polynomial, so we can just replace it with that. + # In other words, we don't have to worry about radicals. + arga, argd = frac_in(arg, self.t) + A = is_deriv_k(arga, argd, self) + if A is not None: + ans, u, const = A + newterm = log(const) + u + self.newf = self.newf.xreplace({log(arg): newterm}) + continue + + else: + arga, argd = frac_in(arg, self.t) + darga = (argd*derivation(Poly(arga, self.t), self) - + arga*derivation(Poly(argd, self.t), self)) + dargd = argd**2 + darg = darga.as_expr()/dargd.as_expr() + self.t = next(self.ts) + self.T.append(self.t) + self.extargs.append(arg) + self.exts.append('log') + self.D.append(cancel(darg.as_expr()/arg).as_poly(self.t, + expand=False)) + if self.dummy: + i = Dummy("i") + else: + i = Symbol('i') + self.Tfuncs += [Lambda(i, log(arg.subs(self.x, i)))] + self.newf = self.newf.xreplace({log(arg): self.t}) + new_extension = True + + return new_extension + + @property + def _important_attrs(self): + """ + Returns some of the more important attributes of self. + + Explanation + =========== + + Used for testing and debugging purposes. + + The attributes are (fa, fd, D, T, Tfuncs, backsubs, + exts, extargs). + """ + return (self.fa, self.fd, self.D, self.T, self.Tfuncs, + self.backsubs, self.exts, self.extargs) + + # NOTE: this printing doesn't follow the Python's standard + # eval(repr(DE)) == DE, where DE is the DifferentialExtension object, + # also this printing is supposed to contain all the important + # attributes of a DifferentialExtension object + def __repr__(self): + # no need to have GeneratorType object printed in it + r = [(attr, getattr(self, attr)) for attr in self.__slots__ + if not isinstance(getattr(self, attr), GeneratorType)] + return self.__class__.__name__ + '(dict(%r))' % (r) + + # fancy printing of DifferentialExtension object + def __str__(self): + return (self.__class__.__name__ + '({fa=%s, fd=%s, D=%s})' % + (self.fa, self.fd, self.D)) + + # should only be used for debugging purposes, internally + # f1 = f2 = log(x) at different places in code execution + # may return D1 != D2 as True, since 'level' or other attribute + # may differ + def __eq__(self, other): + for attr in self.__class__.__slots__: + d1, d2 = getattr(self, attr), getattr(other, attr) + if not (isinstance(d1, GeneratorType) or d1 == d2): + return False + return True + + def reset(self): + """ + Reset self to an initial state. Used by __init__. + """ + self.t = self.x + self.T = [self.x] + self.D = [Poly(1, self.x)] + self.level = -1 + self.exts = [None] + self.extargs = [None] + if self.dummy: + self.ts = numbered_symbols('t', cls=Dummy) + else: + # For testing + self.ts = numbered_symbols('t') + # For various things that we change to make things work that we need to + # change back when we are done. + self.backsubs = [] + self.Tfuncs = [] + self.newf = self.f + + def indices(self, extension): + """ + Parameters + ========== + + extension : str + Represents a valid extension type. + + Returns + ======= + + list: A list of indices of 'exts' where extension of + type 'extension' is present. + + Examples + ======== + + >>> from sympy.integrals.risch import DifferentialExtension + >>> from sympy import log, exp + >>> from sympy.abc import x + >>> DE = DifferentialExtension(log(x) + exp(x), x, handle_first='exp') + >>> DE.indices('log') + [2] + >>> DE.indices('exp') + [1] + + """ + return [i for i, ext in enumerate(self.exts) if ext == extension] + + def increment_level(self): + """ + Increment the level of self. + + Explanation + =========== + + This makes the working differential extension larger. self.level is + given relative to the end of the list (-1, -2, etc.), so we do not need + do worry about it when building the extension. + """ + if self.level >= -1: + raise ValueError("The level of the differential extension cannot " + "be incremented any further.") + + self.level += 1 + self.t = self.T[self.level] + self.d = self.D[self.level] + self.case = self.cases[self.level] + return None + + def decrement_level(self): + """ + Decrease the level of self. + + Explanation + =========== + + This makes the working differential extension smaller. self.level is + given relative to the end of the list (-1, -2, etc.), so we do not need + do worry about it when building the extension. + """ + if self.level <= -len(self.T): + raise ValueError("The level of the differential extension cannot " + "be decremented any further.") + + self.level -= 1 + self.t = self.T[self.level] + self.d = self.D[self.level] + self.case = self.cases[self.level] + return None + + +def update_sets(seq, atoms, func): + s = set(seq) + s = atoms.intersection(s) + new = atoms - s + s.update(list(filter(func, new))) + return list(s) + + +class DecrementLevel: + """ + A context manager for decrementing the level of a DifferentialExtension. + """ + __slots__ = ('DE',) + + def __init__(self, DE): + self.DE = DE + return + + def __enter__(self): + self.DE.decrement_level() + + def __exit__(self, exc_type, exc_value, traceback): + self.DE.increment_level() + + +class NonElementaryIntegralException(Exception): + """ + Exception used by subroutines within the Risch algorithm to indicate to one + another that the function being integrated does not have an elementary + integral in the given differential field. + """ + # TODO: Rewrite algorithms below to use this (?) + + # TODO: Pass through information about why the integral was nonelementary, + # and store that in the resulting NonElementaryIntegral somehow. + pass + + +def gcdex_diophantine(a, b, c): + """ + Extended Euclidean Algorithm, Diophantine version. + + Explanation + =========== + + Given ``a``, ``b`` in K[x] and ``c`` in (a, b), the ideal generated by ``a`` and + ``b``, return (s, t) such that s*a + t*b == c and either s == 0 or s.degree() + < b.degree(). + """ + # Extended Euclidean Algorithm (Diophantine Version) pg. 13 + # TODO: This should go in densetools.py. + # XXX: Better name? + + s, g = a.half_gcdex(b) + s *= c.exquo(g) # Inexact division means c is not in (a, b) + if s and s.degree() >= b.degree(): + _, s = s.div(b) + t = (c - s*a).exquo(b) + return (s, t) + + +def frac_in(f, t, *, cancel=False, **kwargs): + """ + Returns the tuple (fa, fd), where fa and fd are Polys in t. + + Explanation + =========== + + This is a common idiom in the Risch Algorithm functions, so we abstract + it out here. ``f`` should be a basic expression, a Poly, or a tuple (fa, fd), + where fa and fd are either basic expressions or Polys, and f == fa/fd. + **kwargs are applied to Poly. + """ + if isinstance(f, tuple): + fa, fd = f + f = fa.as_expr()/fd.as_expr() + fa, fd = f.as_expr().as_numer_denom() + fa, fd = fa.as_poly(t, **kwargs), fd.as_poly(t, **kwargs) + if cancel: + fa, fd = fa.cancel(fd, include=True) + if fa is None or fd is None: + raise ValueError("Could not turn %s into a fraction in %s." % (f, t)) + return (fa, fd) + + +def as_poly_1t(p, t, z): + """ + (Hackish) way to convert an element ``p`` of K[t, 1/t] to K[t, z]. + + In other words, ``z == 1/t`` will be a dummy variable that Poly can handle + better. + + See issue 5131. + + Examples + ======== + + >>> from sympy import random_poly + >>> from sympy.integrals.risch import as_poly_1t + >>> from sympy.abc import x, z + + >>> p1 = random_poly(x, 10, -10, 10) + >>> p2 = random_poly(x, 10, -10, 10) + >>> p = p1 + p2.subs(x, 1/x) + >>> as_poly_1t(p, x, z).as_expr().subs(z, 1/x) == p + True + """ + # TODO: Use this on the final result. That way, we can avoid answers like + # (...)*exp(-x). + pa, pd = frac_in(p, t, cancel=True) + if not pd.is_monomial: + # XXX: Is there a better Poly exception that we could raise here? + # Either way, if you see this (from the Risch Algorithm) it indicates + # a bug. + raise PolynomialError("%s is not an element of K[%s, 1/%s]." % (p, t, t)) + + t_part, remainder = pa.div(pd) + + ans = t_part.as_poly(t, z, expand=False) + + if remainder: + one = remainder.one + tp = t*one + r = pd.degree() - remainder.degree() + z_part = remainder.transform(one, tp) * tp**r + z_part = z_part.replace(t, z).to_field().quo_ground(pd.LC()) + ans += z_part.as_poly(t, z, expand=False) + + return ans + + +def derivation(p, DE, coefficientD=False, basic=False): + """ + Computes Dp. + + Explanation + =========== + + Given the derivation D with D = d/dx and p is a polynomial in t over + K(x), return Dp. + + If coefficientD is True, it computes the derivation kD + (kappaD), which is defined as kD(sum(ai*Xi**i, (i, 0, n))) == + sum(Dai*Xi**i, (i, 1, n)) (Definition 3.2.2, page 80). X in this case is + T[-1], so coefficientD computes the derivative just with respect to T[:-1], + with T[-1] treated as a constant. + + If ``basic=True``, the returns a Basic expression. Elements of D can still be + instances of Poly. + """ + if basic: + r = 0 + else: + r = Poly(0, DE.t) + + t = DE.t + if coefficientD: + if DE.level <= -len(DE.T): + # 'base' case, the answer is 0. + return r + DE.decrement_level() + + D = DE.D[:len(DE.D) + DE.level + 1] + T = DE.T[:len(DE.T) + DE.level + 1] + + for d, v in zip(D, T): + pv = p.as_poly(v) + if pv is None or basic: + pv = p.as_expr() + + if basic: + r += d.as_expr()*pv.diff(v) + else: + r += (d.as_expr()*pv.diff(v).as_expr()).as_poly(t) + + if basic: + r = cancel(r) + if coefficientD: + DE.increment_level() + + return r + + +def get_case(d, t): + """ + Returns the type of the derivation d. + + Returns one of {'exp', 'tan', 'base', 'primitive', 'other_linear', + 'other_nonlinear'}. + """ + if not d.expr.has(t): + if d.is_one: + return 'base' + return 'primitive' + if d.rem(Poly(t, t)).is_zero: + return 'exp' + if d.rem(Poly(1 + t**2, t)).is_zero: + return 'tan' + if d.degree(t) > 1: + return 'other_nonlinear' + return 'other_linear' + + +def splitfactor(p, DE, coefficientD=False, z=None): + """ + Splitting factorization. + + Explanation + =========== + + Given a derivation D on k[t] and ``p`` in k[t], return (p_n, p_s) in + k[t] x k[t] such that p = p_n*p_s, p_s is special, and each square + factor of p_n is normal. + + Page. 100 + """ + kinv = [1/x for x in DE.T[:DE.level]] + if z: + kinv.append(z) + + One = Poly(1, DE.t, domain=p.get_domain()) + Dp = derivation(p, DE, coefficientD=coefficientD) + # XXX: Is this right? + if p.is_zero: + return (p, One) + + if not p.expr.has(DE.t): + s = p.as_poly(*kinv).gcd(Dp.as_poly(*kinv)).as_poly(DE.t) + n = p.exquo(s) + return (n, s) + + if not Dp.is_zero: + h = p.gcd(Dp).to_field() + g = p.gcd(p.diff(DE.t)).to_field() + s = h.exquo(g) + + if s.degree(DE.t) == 0: + return (p, One) + + q_split = splitfactor(p.exquo(s), DE, coefficientD=coefficientD) + + return (q_split[0], q_split[1]*s) + else: + return (p, One) + + +def splitfactor_sqf(p, DE, coefficientD=False, z=None, basic=False): + """ + Splitting Square-free Factorization. + + Explanation + =========== + + Given a derivation D on k[t] and ``p`` in k[t], returns (N1, ..., Nm) + and (S1, ..., Sm) in k[t]^m such that p = + (N1*N2**2*...*Nm**m)*(S1*S2**2*...*Sm**m) is a splitting + factorization of ``p`` and the Ni and Si are square-free and coprime. + """ + # TODO: This algorithm appears to be faster in every case + # TODO: Verify this and splitfactor() for multiple extensions + kkinv = [1/x for x in DE.T[:DE.level]] + DE.T[:DE.level] + if z: + kkinv = [z] + + S = [] + N = [] + p_sqf = p.sqf_list_include() + if p.is_zero: + return (((p, 1),), ()) + + for pi, i in p_sqf: + Si = pi.as_poly(*kkinv).gcd(derivation(pi, DE, + coefficientD=coefficientD,basic=basic).as_poly(*kkinv)).as_poly(DE.t) + pi = Poly(pi, DE.t) + Si = Poly(Si, DE.t) + Ni = pi.exquo(Si) + if not Si.is_one: + S.append((Si, i)) + if not Ni.is_one: + N.append((Ni, i)) + + return (tuple(N), tuple(S)) + + +def canonical_representation(a, d, DE): + """ + Canonical Representation. + + Explanation + =========== + + Given a derivation D on k[t] and f = a/d in k(t), return (f_p, f_s, + f_n) in k[t] x k(t) x k(t) such that f = f_p + f_s + f_n is the + canonical representation of f (f_p is a polynomial, f_s is reduced + (has a special denominator), and f_n is simple (has a normal + denominator). + """ + # Make d monic + l = Poly(1/d.LC(), DE.t) + a, d = a.mul(l), d.mul(l) + + q, r = a.div(d) + dn, ds = splitfactor(d, DE) + + b, c = gcdex_diophantine(dn.as_poly(DE.t), ds.as_poly(DE.t), r.as_poly(DE.t)) + b, c = b.as_poly(DE.t), c.as_poly(DE.t) + + return (q, (b, ds), (c, dn)) + + +def hermite_reduce(a, d, DE): + """ + Hermite Reduction - Mack's Linear Version. + + Given a derivation D on k(t) and f = a/d in k(t), returns g, h, r in + k(t) such that f = Dg + h + r, h is simple, and r is reduced. + + """ + # Make d monic + l = Poly(1/d.LC(), DE.t) + a, d = a.mul(l), d.mul(l) + + fp, fs, fn = canonical_representation(a, d, DE) + a, d = fn + l = Poly(1/d.LC(), DE.t) + a, d = a.mul(l), d.mul(l) + + ga = Poly(0, DE.t) + gd = Poly(1, DE.t) + + dd = derivation(d, DE) + dm = gcd(d.to_field(), dd.to_field()).as_poly(DE.t) + ds, _ = d.div(dm) + + while dm.degree(DE.t) > 0: + + ddm = derivation(dm, DE) + dm2 = gcd(dm.to_field(), ddm.to_field()) + dms, _ = dm.div(dm2) + ds_ddm = ds.mul(ddm) + ds_ddm_dm, _ = ds_ddm.div(dm) + + b, c = gcdex_diophantine(-ds_ddm_dm.as_poly(DE.t), + dms.as_poly(DE.t), a.as_poly(DE.t)) + b, c = b.as_poly(DE.t), c.as_poly(DE.t) + + db = derivation(b, DE).as_poly(DE.t) + ds_dms, _ = ds.div(dms) + a = c.as_poly(DE.t) - db.mul(ds_dms).as_poly(DE.t) + + ga = ga*dm + b*gd + gd = gd*dm + ga, gd = ga.cancel(gd, include=True) + dm = dm2 + + q, r = a.div(ds) + ga, gd = ga.cancel(gd, include=True) + + r, d = r.cancel(ds, include=True) + rra = q*fs[1] + fp*fs[1] + fs[0] + rrd = fs[1] + rra, rrd = rra.cancel(rrd, include=True) + + return ((ga, gd), (r, d), (rra, rrd)) + + +def polynomial_reduce(p, DE): + """ + Polynomial Reduction. + + Explanation + =========== + + Given a derivation D on k(t) and p in k[t] where t is a nonlinear + monomial over k, return q, r in k[t] such that p = Dq + r, and + deg(r) < deg_t(Dt). + """ + q = Poly(0, DE.t) + while p.degree(DE.t) >= DE.d.degree(DE.t): + m = p.degree(DE.t) - DE.d.degree(DE.t) + 1 + q0 = Poly(DE.t**m, DE.t).mul(Poly(p.as_poly(DE.t).LC()/ + (m*DE.d.LC()), DE.t)) + q += q0 + p = p - derivation(q0, DE) + + return (q, p) + + +def laurent_series(a, d, F, n, DE): + """ + Contribution of ``F`` to the full partial fraction decomposition of A/D. + + Explanation + =========== + + Given a field K of characteristic 0 and ``A``,``D``,``F`` in K[x] with D monic, + nonzero, coprime with A, and ``F`` the factor of multiplicity n in the square- + free factorization of D, return the principal parts of the Laurent series of + A/D at all the zeros of ``F``. + """ + if F.degree()==0: + return 0 + Z = _symbols('z', n) + z = Symbol('z') + Z.insert(0, z) + delta_a = Poly(0, DE.t) + delta_d = Poly(1, DE.t) + + E = d.quo(F**n) + ha, hd = (a, E*Poly(z**n, DE.t)) + dF = derivation(F,DE) + B, _ = gcdex_diophantine(E, F, Poly(1,DE.t)) + C, _ = gcdex_diophantine(dF, F, Poly(1,DE.t)) + + # initialization + F_store = F + V, DE_D_list, H_list= [], [], [] + + for j in range(0, n): + # jth derivative of z would be substituted with dfnth/(j+1) where dfnth =(d^n)f/(dx)^n + F_store = derivation(F_store, DE) + v = (F_store.as_expr())/(j + 1) + V.append(v) + DE_D_list.append(Poly(Z[j + 1],Z[j])) + + DE_new = DifferentialExtension(extension = {'D': DE_D_list}) #a differential indeterminate + for j in range(0, n): + zEha = Poly(z**(n + j), DE.t)*E**(j + 1)*ha + zEhd = hd + Pa, Pd = cancel((zEha, zEhd))[1], cancel((zEha, zEhd))[2] + Q = Pa.quo(Pd) + for i in range(0, j + 1): + Q = Q.subs(Z[i], V[i]) + Dha = (hd*derivation(ha, DE, basic=True).as_poly(DE.t) + + ha*derivation(hd, DE, basic=True).as_poly(DE.t) + + hd*derivation(ha, DE_new, basic=True).as_poly(DE.t) + + ha*derivation(hd, DE_new, basic=True).as_poly(DE.t)) + Dhd = Poly(j + 1, DE.t)*hd**2 + ha, hd = Dha, Dhd + + Ff, _ = F.div(gcd(F, Q)) + F_stara, F_stard = frac_in(Ff, DE.t) + if F_stara.degree(DE.t) - F_stard.degree(DE.t) > 0: + QBC = Poly(Q, DE.t)*B**(1 + j)*C**(n + j) + H = QBC + H_list.append(H) + H = (QBC*F_stard).rem(F_stara) + alphas = real_roots(F_stara) + for alpha in list(alphas): + delta_a = delta_a*Poly((DE.t - alpha)**(n - j), DE.t) + Poly(H.eval(alpha), DE.t) + delta_d = delta_d*Poly((DE.t - alpha)**(n - j), DE.t) + return (delta_a, delta_d, H_list) + + +def recognize_derivative(a, d, DE, z=None): + """ + Compute the squarefree factorization of the denominator of f + and for each Di the polynomial H in K[x] (see Theorem 2.7.1), using the + LaurentSeries algorithm. Write Di = GiEi where Gj = gcd(Hn, Di) and + gcd(Ei,Hn) = 1. Since the residues of f at the roots of Gj are all 0, and + the residue of f at a root alpha of Ei is Hi(a) != 0, f is the derivative of a + rational function if and only if Ei = 1 for each i, which is equivalent to + Di | H[-1] for each i. + """ + flag =True + a, d = a.cancel(d, include=True) + _, r = a.div(d) + Np, Sp = splitfactor_sqf(d, DE, coefficientD=True, z=z) + + j = 1 + for s, _ in Sp: + delta_a, delta_d, H = laurent_series(r, d, s, j, DE) + g = gcd(d, H[-1]).as_poly() + if g is not d: + flag = False + break + j = j + 1 + return flag + + +def recognize_log_derivative(a, d, DE, z=None): + """ + There exists a v in K(x)* such that f = dv/v + where f a rational function if and only if f can be written as f = A/D + where D is squarefree,deg(A) < deg(D), gcd(A, D) = 1, + and all the roots of the Rothstein-Trager resultant are integers. In that case, + any of the Rothstein-Trager, Lazard-Rioboo-Trager or Czichowski algorithm + produces u in K(x) such that du/dx = uf. + """ + + z = z or Dummy('z') + a, d = a.cancel(d, include=True) + _, a = a.div(d) + + pz = Poly(z, DE.t) + Dd = derivation(d, DE) + q = a - pz*Dd + r, _ = d.resultant(q, includePRS=True) + r = Poly(r, z) + Np, Sp = splitfactor_sqf(r, DE, coefficientD=True, z=z) + + for s, _ in Sp: + # TODO also consider the complex roots which should + # turn the flag false + a = real_roots(s.as_poly(z)) + + if not all(j.is_Integer for j in a): + return False + return True + +def residue_reduce(a, d, DE, z=None, invert=True): + """ + Lazard-Rioboo-Rothstein-Trager resultant reduction. + + Explanation + =========== + + Given a derivation ``D`` on k(t) and f in k(t) simple, return g + elementary over k(t) and a Boolean b in {True, False} such that f - + Dg in k[t] if b == True or f + h and f + h - Dg do not have an + elementary integral over k(t) for any h in k (reduced) if b == + False. + + Returns (G, b), where G is a tuple of tuples of the form (s_i, S_i), + such that g = Add(*[RootSum(s_i, lambda z: z*log(S_i(z, t))) for + S_i, s_i in G]). f - Dg is the remaining integral, which is elementary + only if b == True, and hence the integral of f is elementary only if + b == True. + + f - Dg is not calculated in this function because that would require + explicitly calculating the RootSum. Use residue_reduce_derivation(). + """ + # TODO: Use log_to_atan() from rationaltools.py + # If r = residue_reduce(...), then the logarithmic part is given by: + # sum([RootSum(a[0].as_poly(z), lambda i: i*log(a[1].as_expr()).subs(z, + # i)).subs(t, log(x)) for a in r[0]]) + + z = z or Dummy('z') + a, d = a.cancel(d, include=True) + a, d = a.to_field().mul_ground(1/d.LC()), d.to_field().mul_ground(1/d.LC()) + kkinv = [1/x for x in DE.T[:DE.level]] + DE.T[:DE.level] + + if a.is_zero: + return ([], True) + _, a = a.div(d) + + pz = Poly(z, DE.t) + + Dd = derivation(d, DE) + q = a - pz*Dd + + if Dd.degree(DE.t) <= d.degree(DE.t): + r, R = d.resultant(q, includePRS=True) + else: + r, R = q.resultant(d, includePRS=True) + + R_map, H = {}, [] + for i in R: + R_map[i.degree()] = i + + r = Poly(r, z) + Np, Sp = splitfactor_sqf(r, DE, coefficientD=True, z=z) + + for s, i in Sp: + if i == d.degree(DE.t): + s = Poly(s, z).monic() + H.append((s, d)) + else: + h = R_map.get(i) + if h is None: + continue + h_lc = Poly(h.as_poly(DE.t).LC(), DE.t, field=True) + + h_lc_sqf = h_lc.sqf_list_include(all=True) + + for a, j in h_lc_sqf: + h = Poly(h, DE.t, field=True).exquo(Poly(gcd(a, s**j, *kkinv), + DE.t)) + + s = Poly(s, z).monic() + + if invert: + h_lc = Poly(h.as_poly(DE.t).LC(), DE.t, field=True, expand=False) + inv, coeffs = h_lc.as_poly(z, field=True).invert(s), [S.One] + + for coeff in h.coeffs()[1:]: + L = reduced(inv*coeff.as_poly(inv.gens), [s])[1] + coeffs.append(L.as_expr()) + + h = Poly(dict(list(zip(h.monoms(), coeffs))), DE.t) + + H.append((s, h)) + + b = not any(cancel(i.as_expr()).has(DE.t, z) for i, _ in Np) + + return (H, b) + + +def residue_reduce_to_basic(H, DE, z): + """ + Converts the tuple returned by residue_reduce() into a Basic expression. + """ + # TODO: check what Lambda does with RootOf + i = Dummy('i') + s = list(zip(reversed(DE.T), reversed([f(DE.x) for f in DE.Tfuncs]))) + + return sum(RootSum(a[0].as_poly(z), Lambda(i, i*log(a[1].as_expr()).subs( + {z: i}).subs(s))) for a in H) + + +def residue_reduce_derivation(H, DE, z): + """ + Computes the derivation of an expression returned by residue_reduce(). + + In general, this is a rational function in t, so this returns an + as_expr() result. + """ + # TODO: verify that this is correct for multiple extensions + i = Dummy('i') + return S(sum(RootSum(a[0].as_poly(z), Lambda(i, i*derivation(a[1], + DE).as_expr().subs(z, i)/a[1].as_expr().subs(z, i))) for a in H)) + + +def integrate_primitive_polynomial(p, DE): + """ + Integration of primitive polynomials. + + Explanation + =========== + + Given a primitive monomial t over k, and ``p`` in k[t], return q in k[t], + r in k, and a bool b in {True, False} such that r = p - Dq is in k if b is + True, or r = p - Dq does not have an elementary integral over k(t) if b is + False. + """ + Zero = Poly(0, DE.t) + q = Poly(0, DE.t) + + if not p.expr.has(DE.t): + return (Zero, p, True) + + from .prde import limited_integrate + while True: + if not p.expr.has(DE.t): + return (q, p, True) + + Dta, Dtb = frac_in(DE.d, DE.T[DE.level - 1]) + + with DecrementLevel(DE): # We had better be integrating the lowest extension (x) + # with ratint(). + a = p.LC() + aa, ad = frac_in(a, DE.t) + + try: + rv = limited_integrate(aa, ad, [(Dta, Dtb)], DE) + if rv is None: + raise NonElementaryIntegralException + (ba, bd), c = rv + except NonElementaryIntegralException: + return (q, p, False) + + m = p.degree(DE.t) + q0 = c[0].as_poly(DE.t)*Poly(DE.t**(m + 1)/(m + 1), DE.t) + \ + (ba.as_expr()/bd.as_expr()).as_poly(DE.t)*Poly(DE.t**m, DE.t) + + p = p - derivation(q0, DE) + q = q + q0 + + +def integrate_primitive(a, d, DE, z=None): + """ + Integration of primitive functions. + + Explanation + =========== + + Given a primitive monomial t over k and f in k(t), return g elementary over + k(t), i in k(t), and b in {True, False} such that i = f - Dg is in k if b + is True or i = f - Dg does not have an elementary integral over k(t) if b + is False. + + This function returns a Basic expression for the first argument. If b is + True, the second argument is Basic expression in k to recursively integrate. + If b is False, the second argument is an unevaluated Integral, which has + been proven to be nonelementary. + """ + # XXX: a and d must be canceled, or this might return incorrect results + z = z or Dummy("z") + s = list(zip(reversed(DE.T), reversed([f(DE.x) for f in DE.Tfuncs]))) + + g1, h, r = hermite_reduce(a, d, DE) + g2, b = residue_reduce(h[0], h[1], DE, z=z) + if not b: + i = cancel(a.as_expr()/d.as_expr() - (g1[1]*derivation(g1[0], DE) - + g1[0]*derivation(g1[1], DE)).as_expr()/(g1[1]**2).as_expr() - + residue_reduce_derivation(g2, DE, z)) + i = NonElementaryIntegral(cancel(i).subs(s), DE.x) + return ((g1[0].as_expr()/g1[1].as_expr()).subs(s) + + residue_reduce_to_basic(g2, DE, z), i, b) + + # h - Dg2 + r + p = cancel(h[0].as_expr()/h[1].as_expr() - residue_reduce_derivation(g2, + DE, z) + r[0].as_expr()/r[1].as_expr()) + p = p.as_poly(DE.t) + + q, i, b = integrate_primitive_polynomial(p, DE) + + ret = ((g1[0].as_expr()/g1[1].as_expr() + q.as_expr()).subs(s) + + residue_reduce_to_basic(g2, DE, z)) + if not b: + # TODO: This does not do the right thing when b is False + i = NonElementaryIntegral(cancel(i.as_expr()).subs(s), DE.x) + else: + i = cancel(i.as_expr()) + + return (ret, i, b) + + +def integrate_hyperexponential_polynomial(p, DE, z): + """ + Integration of hyperexponential polynomials. + + Explanation + =========== + + Given a hyperexponential monomial t over k and ``p`` in k[t, 1/t], return q in + k[t, 1/t] and a bool b in {True, False} such that p - Dq in k if b is True, + or p - Dq does not have an elementary integral over k(t) if b is False. + """ + t1 = DE.t + dtt = DE.d.exquo(Poly(DE.t, DE.t)) + qa = Poly(0, DE.t) + qd = Poly(1, DE.t) + b = True + + if p.is_zero: + return(qa, qd, b) + + from sympy.integrals.rde import rischDE + + with DecrementLevel(DE): + for i in range(-p.degree(z), p.degree(t1) + 1): + if not i: + continue + elif i < 0: + # If you get AttributeError: 'NoneType' object has no attribute 'nth' + # then this should really not have expand=False + # But it shouldn't happen because p is already a Poly in t and z + a = p.as_poly(z, expand=False).nth(-i) + else: + # If you get AttributeError: 'NoneType' object has no attribute 'nth' + # then this should really not have expand=False + a = p.as_poly(t1, expand=False).nth(i) + + aa, ad = frac_in(a, DE.t, field=True) + aa, ad = aa.cancel(ad, include=True) + iDt = Poly(i, t1)*dtt + iDta, iDtd = frac_in(iDt, DE.t, field=True) + try: + va, vd = rischDE(iDta, iDtd, Poly(aa, DE.t), Poly(ad, DE.t), DE) + va, vd = frac_in((va, vd), t1, cancel=True) + except NonElementaryIntegralException: + b = False + else: + qa = qa*vd + va*Poly(t1**i)*qd + qd *= vd + + return (qa, qd, b) + + +def integrate_hyperexponential(a, d, DE, z=None, conds='piecewise'): + """ + Integration of hyperexponential functions. + + Explanation + =========== + + Given a hyperexponential monomial t over k and f in k(t), return g + elementary over k(t), i in k(t), and a bool b in {True, False} such that + i = f - Dg is in k if b is True or i = f - Dg does not have an elementary + integral over k(t) if b is False. + + This function returns a Basic expression for the first argument. If b is + True, the second argument is Basic expression in k to recursively integrate. + If b is False, the second argument is an unevaluated Integral, which has + been proven to be nonelementary. + """ + # XXX: a and d must be canceled, or this might return incorrect results + z = z or Dummy("z") + s = list(zip(reversed(DE.T), reversed([f(DE.x) for f in DE.Tfuncs]))) + + g1, h, r = hermite_reduce(a, d, DE) + g2, b = residue_reduce(h[0], h[1], DE, z=z) + if not b: + i = cancel(a.as_expr()/d.as_expr() - (g1[1]*derivation(g1[0], DE) - + g1[0]*derivation(g1[1], DE)).as_expr()/(g1[1]**2).as_expr() - + residue_reduce_derivation(g2, DE, z)) + i = NonElementaryIntegral(cancel(i.subs(s)), DE.x) + return ((g1[0].as_expr()/g1[1].as_expr()).subs(s) + + residue_reduce_to_basic(g2, DE, z), i, b) + + # p should be a polynomial in t and 1/t, because Sirr == k[t, 1/t] + # h - Dg2 + r + p = cancel(h[0].as_expr()/h[1].as_expr() - residue_reduce_derivation(g2, + DE, z) + r[0].as_expr()/r[1].as_expr()) + pp = as_poly_1t(p, DE.t, z) + + qa, qd, b = integrate_hyperexponential_polynomial(pp, DE, z) + + i = pp.nth(0, 0) + + ret = ((g1[0].as_expr()/g1[1].as_expr()).subs(s) \ + + residue_reduce_to_basic(g2, DE, z)) + + qas = qa.as_expr().subs(s) + qds = qd.as_expr().subs(s) + if conds == 'piecewise' and DE.x not in qds.free_symbols: + # We have to be careful if the exponent is S.Zero! + + # XXX: Does qd = 0 always necessarily correspond to the exponential + # equaling 1? + ret += Piecewise( + (qas/qds, Ne(qds, 0)), + (integrate((p - i).subs(DE.t, 1).subs(s), DE.x), True) + ) + else: + ret += qas/qds + + if not b: + i = p - (qd*derivation(qa, DE) - qa*derivation(qd, DE)).as_expr()/\ + (qd**2).as_expr() + i = NonElementaryIntegral(cancel(i).subs(s), DE.x) + return (ret, i, b) + + +def integrate_hypertangent_polynomial(p, DE): + """ + Integration of hypertangent polynomials. + + Explanation + =========== + + Given a differential field k such that sqrt(-1) is not in k, a + hypertangent monomial t over k, and p in k[t], return q in k[t] and + c in k such that p - Dq - c*D(t**2 + 1)/(t**1 + 1) is in k and p - + Dq does not have an elementary integral over k(t) if Dc != 0. + """ + # XXX: Make sure that sqrt(-1) is not in k. + q, r = polynomial_reduce(p, DE) + a = DE.d.exquo(Poly(DE.t**2 + 1, DE.t)) + c = Poly(r.nth(1)/(2*a.as_expr()), DE.t) + return (q, c) + + +def integrate_nonlinear_no_specials(a, d, DE, z=None): + """ + Integration of nonlinear monomials with no specials. + + Explanation + =========== + + Given a nonlinear monomial t over k such that Sirr ({p in k[t] | p is + special, monic, and irreducible}) is empty, and f in k(t), returns g + elementary over k(t) and a Boolean b in {True, False} such that f - Dg is + in k if b == True, or f - Dg does not have an elementary integral over k(t) + if b == False. + + This function is applicable to all nonlinear extensions, but in the case + where it returns b == False, it will only have proven that the integral of + f - Dg is nonelementary if Sirr is empty. + + This function returns a Basic expression. + """ + # TODO: Integral from k? + # TODO: split out nonelementary integral + # XXX: a and d must be canceled, or this might not return correct results + z = z or Dummy("z") + s = list(zip(reversed(DE.T), reversed([f(DE.x) for f in DE.Tfuncs]))) + + g1, h, r = hermite_reduce(a, d, DE) + g2, b = residue_reduce(h[0], h[1], DE, z=z) + if not b: + return ((g1[0].as_expr()/g1[1].as_expr()).subs(s) + + residue_reduce_to_basic(g2, DE, z), b) + + # Because f has no specials, this should be a polynomial in t, or else + # there is a bug. + p = cancel(h[0].as_expr()/h[1].as_expr() - residue_reduce_derivation(g2, + DE, z).as_expr() + r[0].as_expr()/r[1].as_expr()).as_poly(DE.t) + q1, q2 = polynomial_reduce(p, DE) + + if q2.expr.has(DE.t): + b = False + else: + b = True + + ret = (cancel(g1[0].as_expr()/g1[1].as_expr() + q1.as_expr()).subs(s) + + residue_reduce_to_basic(g2, DE, z)) + return (ret, b) + + +class NonElementaryIntegral(Integral): + """ + Represents a nonelementary Integral. + + Explanation + =========== + + If the result of integrate() is an instance of this class, it is + guaranteed to be nonelementary. Note that integrate() by default will try + to find any closed-form solution, even in terms of special functions which + may themselves not be elementary. To make integrate() only give + elementary solutions, or, in the cases where it can prove the integral to + be nonelementary, instances of this class, use integrate(risch=True). + In this case, integrate() may raise NotImplementedError if it cannot make + such a determination. + + integrate() uses the deterministic Risch algorithm to integrate elementary + functions or prove that they have no elementary integral. In some cases, + this algorithm can split an integral into an elementary and nonelementary + part, so that the result of integrate will be the sum of an elementary + expression and a NonElementaryIntegral. + + Examples + ======== + + >>> from sympy import integrate, exp, log, Integral + >>> from sympy.abc import x + + >>> a = integrate(exp(-x**2), x, risch=True) + >>> print(a) + Integral(exp(-x**2), x) + >>> type(a) + + + >>> expr = (2*log(x)**2 - log(x) - x**2)/(log(x)**3 - x**2*log(x)) + >>> b = integrate(expr, x, risch=True) + >>> print(b) + -log(-x + log(x))/2 + log(x + log(x))/2 + Integral(1/log(x), x) + >>> type(b.atoms(Integral).pop()) + + + """ + # TODO: This is useful in and of itself, because isinstance(result, + # NonElementaryIntegral) will tell if the integral has been proven to be + # elementary. But should we do more? Perhaps a no-op .doit() if + # elementary=True? Or maybe some information on why the integral is + # nonelementary. + pass + + +def risch_integrate(f, x, extension=None, handle_first='log', + separate_integral=False, rewrite_complex=None, + conds='piecewise'): + r""" + The Risch Integration Algorithm. + + Explanation + =========== + + Only transcendental functions are supported. Currently, only exponentials + and logarithms are supported, but support for trigonometric functions is + forthcoming. + + If this function returns an unevaluated Integral in the result, it means + that it has proven that integral to be nonelementary. Any errors will + result in raising NotImplementedError. The unevaluated Integral will be + an instance of NonElementaryIntegral, a subclass of Integral. + + handle_first may be either 'exp' or 'log'. This changes the order in + which the extension is built, and may result in a different (but + equivalent) solution (for an example of this, see issue 5109). It is also + possible that the integral may be computed with one but not the other, + because not all cases have been implemented yet. It defaults to 'log' so + that the outer extension is exponential when possible, because more of the + exponential case has been implemented. + + If ``separate_integral`` is ``True``, the result is returned as a tuple (ans, i), + where the integral is ans + i, ans is elementary, and i is either a + NonElementaryIntegral or 0. This useful if you want to try further + integrating the NonElementaryIntegral part using other algorithms to + possibly get a solution in terms of special functions. It is False by + default. + + Examples + ======== + + >>> from sympy.integrals.risch import risch_integrate + >>> from sympy import exp, log, pprint + >>> from sympy.abc import x + + First, we try integrating exp(-x**2). Except for a constant factor of + 2/sqrt(pi), this is the famous error function. + + >>> pprint(risch_integrate(exp(-x**2), x)) + / + | + | 2 + | -x + | e dx + | + / + + The unevaluated Integral in the result means that risch_integrate() has + proven that exp(-x**2) does not have an elementary anti-derivative. + + In many cases, risch_integrate() can split out the elementary + anti-derivative part from the nonelementary anti-derivative part. + For example, + + >>> pprint(risch_integrate((2*log(x)**2 - log(x) - x**2)/(log(x)**3 - + ... x**2*log(x)), x)) + / + | + log(-x + log(x)) log(x + log(x)) | 1 + - ---------------- + --------------- + | ------ dx + 2 2 | log(x) + | + / + + This means that it has proven that the integral of 1/log(x) is + nonelementary. This function is also known as the logarithmic integral, + and is often denoted as Li(x). + + risch_integrate() currently only accepts purely transcendental functions + with exponentials and logarithms, though note that this can include + nested exponentials and logarithms, as well as exponentials with bases + other than E. + + >>> pprint(risch_integrate(exp(x)*exp(exp(x)), x)) + / x\ + \e / + e + >>> pprint(risch_integrate(exp(exp(x)), x)) + / + | + | / x\ + | \e / + | e dx + | + / + + >>> pprint(risch_integrate(x*x**x*log(x) + x**x + x*x**x, x)) + x + x*x + >>> pprint(risch_integrate(x**x, x)) + / + | + | x + | x dx + | + / + + >>> pprint(risch_integrate(-1/(x*log(x)*log(log(x))**2), x)) + 1 + ----------- + log(log(x)) + + """ + f = S(f) + + DE = extension or DifferentialExtension(f, x, handle_first=handle_first, + dummy=True, rewrite_complex=rewrite_complex) + fa, fd = DE.fa, DE.fd + + result = S.Zero + for case in reversed(DE.cases): + if not fa.expr.has(DE.t) and not fd.expr.has(DE.t) and not case == 'base': + DE.decrement_level() + fa, fd = frac_in((fa, fd), DE.t) + continue + + fa, fd = fa.cancel(fd, include=True) + if case == 'exp': + ans, i, b = integrate_hyperexponential(fa, fd, DE, conds=conds) + elif case == 'primitive': + ans, i, b = integrate_primitive(fa, fd, DE) + elif case == 'base': + # XXX: We can't call ratint() directly here because it doesn't + # handle polynomials correctly. + ans = integrate(fa.as_expr()/fd.as_expr(), DE.x, risch=False) + b = False + i = S.Zero + else: + raise NotImplementedError("Only exponential and logarithmic " + "extensions are currently supported.") + + result += ans + if b: + DE.decrement_level() + fa, fd = frac_in(i, DE.t) + else: + result = result.subs(DE.backsubs) + if not i.is_zero: + i = NonElementaryIntegral(i.function.subs(DE.backsubs),i.limits) + if not separate_integral: + result += i + return result + else: + + if isinstance(i, NonElementaryIntegral): + return (result, i) + else: + return (result, 0) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/singularityfunctions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/singularityfunctions.py new file mode 100644 index 0000000000000000000000000000000000000000..3e33d0542c45b67b193f17e00c25837f3a82109a --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/singularityfunctions.py @@ -0,0 +1,63 @@ +from sympy.functions import SingularityFunction, DiracDelta +from sympy.integrals import integrate + + +def singularityintegrate(f, x): + """ + This function handles the indefinite integrations of Singularity functions. + The ``integrate`` function calls this function internally whenever an + instance of SingularityFunction is passed as argument. + + Explanation + =========== + + The idea for integration is the following: + + - If we are dealing with a SingularityFunction expression, + i.e. ``SingularityFunction(x, a, n)``, we just return + ``SingularityFunction(x, a, n + 1)/(n + 1)`` if ``n >= 0`` and + ``SingularityFunction(x, a, n + 1)`` if ``n < 0``. + + - If the node is a multiplication or power node having a + SingularityFunction term we rewrite the whole expression in terms of + Heaviside and DiracDelta and then integrate the output. Lastly, we + rewrite the output of integration back in terms of SingularityFunction. + + - If none of the above case arises, we return None. + + Examples + ======== + + >>> from sympy.integrals.singularityfunctions import singularityintegrate + >>> from sympy import SingularityFunction, symbols, Function + >>> x, a, n, y = symbols('x a n y') + >>> f = Function('f') + >>> singularityintegrate(SingularityFunction(x, a, 3), x) + SingularityFunction(x, a, 4)/4 + >>> singularityintegrate(5*SingularityFunction(x, 5, -2), x) + 5*SingularityFunction(x, 5, -1) + >>> singularityintegrate(6*SingularityFunction(x, 5, -1), x) + 6*SingularityFunction(x, 5, 0) + >>> singularityintegrate(x*SingularityFunction(x, 0, -1), x) + 0 + >>> singularityintegrate(SingularityFunction(x, 1, -1) * f(x), x) + f(1)*SingularityFunction(x, 1, 0) + + """ + + if not f.has(SingularityFunction): + return None + + if isinstance(f, SingularityFunction): + x, a, n = f.args + if n.is_positive or n.is_zero: + return SingularityFunction(x, a, n + 1)/(n + 1) + elif n in (-1, -2, -3, -4): + return SingularityFunction(x, a, n + 1) + + if f.is_Mul or f.is_Pow: + + expr = f.rewrite(DiracDelta) + expr = integrate(expr, x) + return expr.rewrite(SingularityFunction) + return None diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_deltafunctions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_deltafunctions.py new file mode 100644 index 0000000000000000000000000000000000000000..d4fd567349b50f795e08d583fd08db67b1596577 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_deltafunctions.py @@ -0,0 +1,79 @@ +from sympy.core.function import Function +from sympy.core.numbers import (Rational, pi) +from sympy.core.singleton import S +from sympy.core.symbol import symbols +from sympy.functions.elementary.trigonometric import (cos, sin) +from sympy.functions.special.delta_functions import (DiracDelta, Heaviside) +from sympy.integrals.deltafunctions import change_mul, deltaintegrate + +f = Function("f") +x_1, x_2, x, y, z = symbols("x_1 x_2 x y z") + + +def test_change_mul(): + assert change_mul(x, x) == (None, None) + assert change_mul(x*y, x) == (None, None) + assert change_mul(x*y*DiracDelta(x), x) == (DiracDelta(x), x*y) + assert change_mul(x*y*DiracDelta(x)*DiracDelta(y), x) == \ + (DiracDelta(x), x*y*DiracDelta(y)) + assert change_mul(DiracDelta(x)**2, x) == \ + (DiracDelta(x), DiracDelta(x)) + assert change_mul(y*DiracDelta(x)**2, x) == \ + (DiracDelta(x), y*DiracDelta(x)) + + +def test_deltaintegrate(): + assert deltaintegrate(x, x) is None + assert deltaintegrate(x + DiracDelta(x), x) is None + assert deltaintegrate(DiracDelta(x, 0), x) == Heaviside(x) + for n in range(10): + assert deltaintegrate(DiracDelta(x, n + 1), x) == DiracDelta(x, n) + assert deltaintegrate(DiracDelta(x), x) == Heaviside(x) + assert deltaintegrate(DiracDelta(-x), x) == Heaviside(x) + assert deltaintegrate(DiracDelta(x - y), x) == Heaviside(x - y) + assert deltaintegrate(DiracDelta(y - x), x) == Heaviside(x - y) + + assert deltaintegrate(x*DiracDelta(x), x) == 0 + assert deltaintegrate((x - y)*DiracDelta(x - y), x) == 0 + + assert deltaintegrate(DiracDelta(x)**2, x) == DiracDelta(0)*Heaviside(x) + assert deltaintegrate(y*DiracDelta(x)**2, x) == \ + y*DiracDelta(0)*Heaviside(x) + assert deltaintegrate(DiracDelta(x, 1), x) == DiracDelta(x, 0) + assert deltaintegrate(y*DiracDelta(x, 1), x) == y*DiracDelta(x, 0) + assert deltaintegrate(DiracDelta(x, 1)**2, x) == -DiracDelta(0, 2)*Heaviside(x) + assert deltaintegrate(y*DiracDelta(x, 1)**2, x) == -y*DiracDelta(0, 2)*Heaviside(x) + + + assert deltaintegrate(DiracDelta(x) * f(x), x) == f(0) * Heaviside(x) + assert deltaintegrate(DiracDelta(-x) * f(x), x) == f(0) * Heaviside(x) + assert deltaintegrate(DiracDelta(x - 1) * f(x), x) == f(1) * Heaviside(x - 1) + assert deltaintegrate(DiracDelta(1 - x) * f(x), x) == f(1) * Heaviside(x - 1) + assert deltaintegrate(DiracDelta(x**2 + x - 2), x) == \ + Heaviside(x - 1)/3 + Heaviside(x + 2)/3 + + p = cos(x)*(DiracDelta(x) + DiracDelta(x**2 - 1))*sin(x)*(x - pi) + assert deltaintegrate(p, x) - (-pi*(cos(1)*Heaviside(-1 + x)*sin(1)/2 - \ + cos(1)*Heaviside(1 + x)*sin(1)/2) + \ + cos(1)*Heaviside(1 + x)*sin(1)/2 + \ + cos(1)*Heaviside(-1 + x)*sin(1)/2) == 0 + + p = x_2*DiracDelta(x - x_2)*DiracDelta(x_2 - x_1) + assert deltaintegrate(p, x_2) == x*DiracDelta(x - x_1)*Heaviside(x_2 - x) + + p = x*y**2*z*DiracDelta(y - x)*DiracDelta(y - z)*DiracDelta(x - z) + assert deltaintegrate(p, y) == x**3*z*DiracDelta(x - z)**2*Heaviside(y - x) + assert deltaintegrate((x + 1)*DiracDelta(2*x), x) == S.Half * Heaviside(x) + assert deltaintegrate((x + 1)*DiracDelta(x*Rational(2, 3) + Rational(4, 9)), x) == \ + S.Half * Heaviside(x + Rational(2, 3)) + + a, b, c = symbols('a b c', commutative=False) + assert deltaintegrate(DiracDelta(x - y)*f(x - b)*f(x - a), x) == \ + f(y - b)*f(y - a)*Heaviside(x - y) + + p = f(x - a)*DiracDelta(x - y)*f(x - c)*f(x - b) + assert deltaintegrate(p, x) == f(y - a)*f(y - c)*f(y - b)*Heaviside(x - y) + + p = DiracDelta(x - z)*f(x - b)*f(x - a)*DiracDelta(x - y) + assert deltaintegrate(p, x) == DiracDelta(y - z)*f(y - b)*f(y - a) * \ + Heaviside(x - y) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_failing_integrals.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_failing_integrals.py new file mode 100644 index 0000000000000000000000000000000000000000..9bb434cf0009cd96ad2b7882d109b7fbe23193c2 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_failing_integrals.py @@ -0,0 +1,277 @@ +# A collection of failing integrals from the issues. + +from sympy.core.numbers import (I, Rational, oo, pi) +from sympy.core.singleton import S +from sympy.core.symbol import symbols +from sympy.functions.elementary.complexes import sign +from sympy.functions.elementary.exponential import (exp, log) +from sympy.functions.elementary.hyperbolic import (sech, sinh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import (acos, atan, cos, sin, tan) +from sympy.functions.special.delta_functions import DiracDelta +from sympy.functions.special.gamma_functions import gamma +from sympy.integrals.integrals import (Integral, integrate) +from sympy.simplify.fu import fu + + +from sympy.testing.pytest import XFAIL, slow, tooslow + +from sympy.abc import x, k, c, y, b, h, a, m, z, n, t + + +@tooslow +@XFAIL +def test_issue_3880(): + # integrate_hyperexponential(Poly(t*2*(1 - t0**2)*t0*(x**3 + x**2), t), Poly((1 + t0**2)**2*2*(x**2 + x + 1), t), [Poly(1, x), Poly(1 + t0**2, t0), Poly(t, t)], [x, t0, t], [exp, tan]) + assert not integrate(exp(x)*cos(2*x)*sin(2*x) * (x**3 + x**2)/(2*(x**2 + x + 1)), x).has(Integral) + + +def test_issue_4212_real(): + xr = symbols('xr', real=True) + negabsx = Piecewise((-xr, xr < 0), (xr, True)) + assert integrate(sign(xr), xr) == negabsx + + +@XFAIL +def test_issue_4212(): + # XXX: Maybe this should be expected to fail without real assumptions on x. + # As a complex function sign(x) is not analytic and so there is no complex + # function whose complex derivative is sign(x). With real assumptions this + # works (see test_issue_4212_real above). + assert not integrate(sign(x), x).has(Integral) + + +def test_issue_4511(): + # This works, but gives a slightly over-complicated answer. + f = integrate(cos(x)**2 / (1 - sin(x)), x) + assert fu(f) == x - cos(x) - 1 + assert f == ((x*tan(x/2)**2 + x - 2)/(tan(x/2)**2 + 1)).expand() + + +def test_integrate_DiracDelta_no_meijerg(): + assert integrate(integrate(integrate( + DiracDelta(x - y - z), (z, 0, oo)), (y, 0, 1), meijerg=False), (x, 0, 1)) == S.Half + + +@XFAIL +def test_integrate_DiracDelta_fails(): + # issue 6427 + # works without meijerg. See test_integrate_DiracDelta_no_meijerg above. + assert integrate(integrate(integrate( + DiracDelta(x - y - z), (z, 0, oo)), (y, 0, 1)), (x, 0, 1)) == S.Half + + +@XFAIL +@slow +def test_issue_4525(): + # Warning: takes a long time + assert not integrate((x**m * (1 - x)**n * (a + b*x + c*x**2))/(1 + x**2), (x, 0, 1)).has(Integral) + + +@XFAIL +@tooslow +def test_issue_4540(): + # Note, this integral is probably nonelementary + assert not integrate( + (sin(1/x) - x*exp(x)) / + ((-sin(1/x) + x*exp(x))*x + x*sin(1/x)), x).has(Integral) + + +@XFAIL +@slow +def test_issue_4891(): + # Requires the hypergeometric function. + assert not integrate(cos(x)**y, x).has(Integral) + + +@XFAIL +@slow +def test_issue_1796a(): + assert not integrate(exp(2*b*x)*exp(-a*x**2), x).has(Integral) + + +@XFAIL +def test_issue_4895b(): + assert not integrate(exp(2*b*x)*exp(-a*x**2), (x, -oo, 0)).has(Integral) + + +@XFAIL +def test_issue_4895c(): + assert not integrate(exp(2*b*x)*exp(-a*x**2), (x, -oo, oo)).has(Integral) + + +@XFAIL +def test_issue_4895d(): + assert not integrate(exp(2*b*x)*exp(-a*x**2), (x, 0, oo)).has(Integral) + + +@XFAIL +@slow +def test_issue_4941(): + assert not integrate(sqrt(1 + sinh(x/20)**2), (x, -25, 25)).has(Integral) + + +@XFAIL +def test_issue_4992(): + # Nonelementary integral. Requires hypergeometric/Meijer-G handling. + assert not integrate(log(x) * x**(k - 1) * exp(-x) / gamma(k), (x, 0, oo)).has(Integral) + + +@XFAIL +def test_issue_16396a(): + i = integrate(1/(1+sqrt(tan(x))), (x, pi/3, pi/6)) + assert not i.has(Integral) + + +@XFAIL +def test_issue_16396b(): + i = integrate(x*sin(x)/(1+cos(x)**2), (x, 0, pi)) + assert not i.has(Integral) + + +@XFAIL +def test_issue_16046(): + assert integrate(exp(exp(I*x)), [x, 0, 2*pi]) == 2*pi + + +@XFAIL +def test_issue_15925a(): + assert not integrate(sqrt((1+sin(x))**2+(cos(x))**2), (x, -pi/2, pi/2)).has(Integral) + + +def test_issue_15925b(): + f = sqrt((-12*cos(x)**2*sin(x))**2+(12*cos(x)*sin(x)**2)**2) + assert integrate(f, (x, 0, pi/6)) == Rational(3, 2) + + +@XFAIL +def test_issue_15925b_manual(): + assert not integrate(sqrt((-12*cos(x)**2*sin(x))**2+(12*cos(x)*sin(x)**2)**2), + (x, 0, pi/6), manual=True).has(Integral) + + +@XFAIL +@tooslow +def test_issue_15227(): + i = integrate(log(1-x)*log((1+x)**2)/x, (x, 0, 1)) + assert not i.has(Integral) + # assert i == -5*zeta(3)/4 + + +@XFAIL +@slow +def test_issue_14716(): + i = integrate(log(x + 5)*cos(pi*x),(x, S.Half, 1)) + assert not i.has(Integral) + # Mathematica can not solve it either, but + # integrate(log(x + 5)*cos(pi*x),(x, S.Half, 1)).transform(x, y - 5).doit() + # works + # assert i == -log(Rational(11, 2))/pi - Si(pi*Rational(11, 2))/pi + Si(6*pi)/pi + + +@XFAIL +def test_issue_14709a(): + i = integrate(x*acos(1 - 2*x/h), (x, 0, h)) + assert not i.has(Integral) + # assert i == 5*h**2*pi/16 + + +@slow +@XFAIL +def test_issue_14398(): + assert not integrate(exp(x**2)*cos(x), x).has(Integral) + + +@XFAIL +def test_issue_14074(): + i = integrate(log(sin(x)), (x, 0, pi/2)) + assert not i.has(Integral) + # assert i == -pi*log(2)/2 + + +@XFAIL +@slow +def test_issue_14078b(): + i = integrate((atan(4*x)-atan(2*x))/x, (x, 0, oo)) + assert not i.has(Integral) + # assert i == pi*log(2)/2 + + +@XFAIL +def test_issue_13792(): + i = integrate(log(1/x) / (1 - x), (x, 0, 1)) + assert not i.has(Integral) + # assert i in [polylog(2, -exp_polar(I*pi)), pi**2/6] + + +@XFAIL +def test_issue_11845a(): + assert not integrate(exp(y - x**3), (x, 0, 1)).has(Integral) + + +@XFAIL +def test_issue_11845b(): + assert not integrate(exp(-y - x**3), (x, 0, 1)).has(Integral) + + +@XFAIL +def test_issue_11813(): + assert not integrate((a - x)**Rational(-1, 2)*x, (x, 0, a)).has(Integral) + + +@XFAIL +def test_issue_11254c(): + assert not integrate(sech(x)**2, (x, 0, 1)).has(Integral) + + +@XFAIL +def test_issue_10584(): + assert not integrate(sqrt(x**2 + 1/x**2), x).has(Integral) + + +@XFAIL +def test_issue_9101(): + assert not integrate(log(x + sqrt(x**2 + y**2 + z**2)), z).has(Integral) + + +@XFAIL +def test_issue_7147(): + assert not integrate(x/sqrt(a*x**2 + b*x + c)**3, x).has(Integral) + + +@XFAIL +def test_issue_7109(): + assert not integrate(sqrt(a**2/(a**2 - x**2)), x).has(Integral) + + +@XFAIL +def test_integrate_Piecewise_rational_over_reals(): + f = Piecewise( + (0, t - 478.515625*pi < 0), + (13.2075145209219*pi/(0.000871222*t + 0.995)**2, t - 478.515625*pi >= 0)) + + assert abs((integrate(f, (t, 0, oo)) - 15235.9375*pi).evalf()) <= 1e-7 + + +@XFAIL +def test_issue_4311_slow(): + # Not slow when bypassing heurish + assert not integrate(x*abs(9-x**2), x).has(Integral) + +@XFAIL +def test_issue_20370(): + a = symbols('a', positive=True) + assert integrate((1 + a * cos(x))**-1, (x, 0, 2 * pi)) == (2 * pi / sqrt(1 - a**2)) + + +@XFAIL +def test_polylog(): + # log(1/x)*log(x+1)-polylog(2, -x) + assert not integrate(log(1/x)/(x + 1), x).has(Integral) + + +@XFAIL +def test_polylog_manual(): + # Make sure _parts_rule does not go into an infinite loop here + assert not integrate(log(1/x)/(x + 1), x, manual=True).has(Integral) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_heurisch.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_heurisch.py new file mode 100644 index 0000000000000000000000000000000000000000..f02556dedd597721529cab47bf53609110e0ce2a --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_heurisch.py @@ -0,0 +1,417 @@ +from sympy.concrete.summations import Sum +from sympy.core.add import Add +from sympy.core.function import (Derivative, Function, diff) +from sympy.core.numbers import (I, Rational, pi) +from sympy.core.relational import Eq, Ne +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.exponential import (LambertW, exp, log) +from sympy.functions.elementary.hyperbolic import (asinh, cosh, sinh, tanh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import (acos, asin, atan, cos, sin, tan) +from sympy.functions.special.bessel import (besselj, besselk, bessely, jn) +from sympy.functions.special.error_functions import erf +from sympy.integrals.integrals import Integral +from sympy.logic.boolalg import And +from sympy.matrices import Matrix +from sympy.simplify.ratsimp import ratsimp +from sympy.simplify.simplify import simplify +from sympy.integrals.heurisch import components, heurisch, heurisch_wrapper +from sympy.testing.pytest import XFAIL, slow +from sympy.integrals.integrals import integrate +from sympy import S + +x, y, z, nu = symbols('x,y,z,nu') +f = Function('f') + + +def test_components(): + assert components(x*y, x) == {x} + assert components(1/(x + y), x) == {x} + assert components(sin(x), x) == {sin(x), x} + assert components(sin(x)*sqrt(log(x)), x) == \ + {log(x), sin(x), sqrt(log(x)), x} + assert components(x*sin(exp(x)*y), x) == \ + {sin(y*exp(x)), x, exp(x)} + assert components(x**Rational(17, 54)/sqrt(sin(x)), x) == \ + {sin(x), x**Rational(1, 54), sqrt(sin(x)), x} + + assert components(f(x), x) == \ + {x, f(x)} + assert components(Derivative(f(x), x), x) == \ + {x, f(x), Derivative(f(x), x)} + assert components(f(x)*diff(f(x), x), x) == \ + {x, f(x), Derivative(f(x), x), Derivative(f(x), x)} + + +def test_issue_10680(): + assert isinstance(integrate(x**log(x**log(x**log(x))),x), Integral) + + +def test_issue_21166(): + assert integrate(sin(x/sqrt(abs(x))), (x, -1, 1)) == 0 + + +def test_heurisch_polynomials(): + assert heurisch(1, x) == x + assert heurisch(x, x) == x**2/2 + assert heurisch(x**17, x) == x**18/18 + # For coverage + assert heurisch_wrapper(y, x) == y*x + + +def test_heurisch_fractions(): + assert heurisch(1/x, x) == log(x) + assert heurisch(1/(2 + x), x) == log(x + 2) + assert heurisch(1/(x + sin(y)), x) == log(x + sin(y)) + + # Up to a constant, where C = pi*I*Rational(5, 12), Mathematica gives identical + # result in the first case. The difference is because SymPy changes + # signs of expressions without any care. + # XXX ^ ^ ^ is this still correct? + assert heurisch(5*x**5/( + 2*x**6 - 5), x) in [5*log(2*x**6 - 5) / 12, 5*log(-2*x**6 + 5) / 12] + assert heurisch(5*x**5/(2*x**6 + 5), x) == 5*log(2*x**6 + 5) / 12 + + assert heurisch(1/x**2, x) == -1/x + assert heurisch(-1/x**5, x) == 1/(4*x**4) + + +def test_heurisch_log(): + assert heurisch(log(x), x) == x*log(x) - x + assert heurisch(log(3*x), x) == -x + x*log(3) + x*log(x) + assert heurisch(log(x**2), x) in [x*log(x**2) - 2*x, 2*x*log(x) - 2*x] + + +def test_heurisch_exp(): + assert heurisch(exp(x), x) == exp(x) + assert heurisch(exp(-x), x) == -exp(-x) + assert heurisch(exp(17*x), x) == exp(17*x) / 17 + assert heurisch(x*exp(x), x) == x*exp(x) - exp(x) + assert heurisch(x*exp(x**2), x) == exp(x**2) / 2 + + assert heurisch(exp(-x**2), x) is None + + assert heurisch(2**x, x) == 2**x/log(2) + assert heurisch(x*2**x, x) == x*2**x/log(2) - 2**x*log(2)**(-2) + + assert heurisch(Integral(x**z*y, (y, 1, 2), (z, 2, 3)).function, x) == (x*x**z*y)/(z+1) + assert heurisch(Sum(x**z, (z, 1, 2)).function, z) == x**z/log(x) + + # https://github.com/sympy/sympy/issues/23707 + anti = -exp(z)/(sqrt(x - y)*exp(z*sqrt(x - y)) - exp(z*sqrt(x - y))) + assert heurisch(exp(z)*exp(-z*sqrt(x - y)), z) == anti + + +def test_heurisch_trigonometric(): + assert heurisch(sin(x), x) == -cos(x) + assert heurisch(pi*sin(x) + 1, x) == x - pi*cos(x) + + assert heurisch(cos(x), x) == sin(x) + assert heurisch(tan(x), x) in [ + log(1 + tan(x)**2)/2, + log(tan(x) + I) + I*x, + log(tan(x) - I) - I*x, + ] + + assert heurisch(sin(x)*sin(y), x) == -cos(x)*sin(y) + assert heurisch(sin(x)*sin(y), y) == -cos(y)*sin(x) + + # gives sin(x) in answer when run via setup.py and cos(x) when run via py.test + assert heurisch(sin(x)*cos(x), x) in [sin(x)**2 / 2, -cos(x)**2 / 2] + assert heurisch(cos(x)/sin(x), x) == log(sin(x)) + + assert heurisch(x*sin(7*x), x) == sin(7*x) / 49 - x*cos(7*x) / 7 + assert heurisch(1/pi/4 * x**2*cos(x), x) == 1/pi/4*(x**2*sin(x) - + 2*sin(x) + 2*x*cos(x)) + + assert heurisch(acos(x/4) * asin(x/4), x) == 2*x - (sqrt(16 - x**2))*asin(x/4) \ + + (sqrt(16 - x**2))*acos(x/4) + x*asin(x/4)*acos(x/4) + + assert heurisch(sin(x)/(cos(x)**2+1), x) == -atan(cos(x)) #fixes issue 13723 + assert heurisch(1/(cos(x)+2), x) == 2*sqrt(3)*atan(sqrt(3)*tan(x/2)/3)/3 + assert heurisch(2*sin(x)*cos(x)/(sin(x)**4 + 1), x) == atan(sqrt(2)*sin(x) + - 1) - atan(sqrt(2)*sin(x) + 1) + + assert heurisch(1/cosh(x), x) == 2*atan(tanh(x/2)) + + +def test_heurisch_hyperbolic(): + assert heurisch(sinh(x), x) == cosh(x) + assert heurisch(cosh(x), x) == sinh(x) + + assert heurisch(x*sinh(x), x) == x*cosh(x) - sinh(x) + assert heurisch(x*cosh(x), x) == x*sinh(x) - cosh(x) + + assert heurisch( + x*asinh(x/2), x) == x**2*asinh(x/2)/2 + asinh(x/2) - x*sqrt(4 + x**2)/4 + + +def test_heurisch_mixed(): + assert heurisch(sin(x)*exp(x), x) == exp(x)*sin(x)/2 - exp(x)*cos(x)/2 + assert heurisch(sin(x/sqrt(-x)), x) == 2*x*cos(x/sqrt(-x))/sqrt(-x) - 2*sin(x/sqrt(-x)) + + +def test_heurisch_radicals(): + assert heurisch(1/sqrt(x), x) == 2*sqrt(x) + assert heurisch(1/sqrt(x)**3, x) == -2/sqrt(x) + assert heurisch(sqrt(x)**3, x) == 2*sqrt(x)**5/5 + + assert heurisch(sin(x)*sqrt(cos(x)), x) == -2*sqrt(cos(x))**3/3 + y = Symbol('y') + assert heurisch(sin(y*sqrt(x)), x) == 2/y**2*sin(y*sqrt(x)) - \ + 2*sqrt(x)*cos(y*sqrt(x))/y + assert heurisch_wrapper(sin(y*sqrt(x)), x) == Piecewise( + (-2*sqrt(x)*cos(sqrt(x)*y)/y + 2*sin(sqrt(x)*y)/y**2, Ne(y, 0)), + (0, True)) + y = Symbol('y', positive=True) + assert heurisch_wrapper(sin(y*sqrt(x)), x) == 2/y**2*sin(y*sqrt(x)) - \ + 2*sqrt(x)*cos(y*sqrt(x))/y + + +def test_heurisch_special(): + assert heurisch(erf(x), x) == x*erf(x) + exp(-x**2)/sqrt(pi) + assert heurisch(exp(-x**2)*erf(x), x) == sqrt(pi)*erf(x)**2 / 4 + + +def test_heurisch_symbolic_coeffs(): + assert heurisch(1/(x + y), x) == log(x + y) + assert heurisch(1/(x + sqrt(2)), x) == log(x + sqrt(2)) + assert simplify(diff(heurisch(log(x + y + z), y), y)) == log(x + y + z) + + +def test_heurisch_symbolic_coeffs_1130(): + y = Symbol('y') + assert heurisch_wrapper(1/(x**2 + y), x) == Piecewise( + (log(x - sqrt(-y))/(2*sqrt(-y)) - log(x + sqrt(-y))/(2*sqrt(-y)), + Ne(y, 0)), (-1/x, True)) + y = Symbol('y', positive=True) + assert heurisch_wrapper(1/(x**2 + y), x) == (atan(x/sqrt(y))/sqrt(y)) + + +def test_heurisch_hacking(): + assert heurisch(sqrt(1 + 7*x**2), x, hints=[]) == \ + x*sqrt(1 + 7*x**2)/2 + sqrt(7)*asinh(sqrt(7)*x)/14 + assert heurisch(sqrt(1 - 7*x**2), x, hints=[]) == \ + x*sqrt(1 - 7*x**2)/2 + sqrt(7)*asin(sqrt(7)*x)/14 + + assert heurisch(1/sqrt(1 + 7*x**2), x, hints=[]) == \ + sqrt(7)*asinh(sqrt(7)*x)/7 + assert heurisch(1/sqrt(1 - 7*x**2), x, hints=[]) == \ + sqrt(7)*asin(sqrt(7)*x)/7 + + assert heurisch(exp(-7*x**2), x, hints=[]) == \ + sqrt(7*pi)*erf(sqrt(7)*x)/14 + + assert heurisch(1/sqrt(9 - 4*x**2), x, hints=[]) == \ + asin(x*Rational(2, 3))/2 + + assert heurisch(1/sqrt(9 + 4*x**2), x, hints=[]) == \ + asinh(x*Rational(2, 3))/2 + + assert heurisch(1/sqrt(3*x**2-4), x, hints=[]) == \ + sqrt(3)*log(3*x + sqrt(3)*sqrt(3*x**2 - 4))/3 + + +def test_heurisch_function(): + assert heurisch(f(x), x) is None + +@XFAIL +def test_heurisch_function_derivative(): + # TODO: it looks like this used to work just by coincindence and + # thanks to sloppy implementation. Investigate why this used to + # work at all and if support for this can be restored. + + df = diff(f(x), x) + + assert heurisch(f(x)*df, x) == f(x)**2/2 + assert heurisch(f(x)**2*df, x) == f(x)**3/3 + assert heurisch(df/f(x), x) == log(f(x)) + + +def test_heurisch_wrapper(): + f = 1/(y + x) + assert heurisch_wrapper(f, x) == log(x + y) + f = 1/(y - x) + assert heurisch_wrapper(f, x) == -log(x - y) + f = 1/((y - x)*(y + x)) + assert heurisch_wrapper(f, x) == Piecewise( + (-log(x - y)/(2*y) + log(x + y)/(2*y), Ne(y, 0)), (1/x, True)) + # issue 6926 + f = sqrt(x**2/((y - x)*(y + x))) + assert heurisch_wrapper(f, x) == x*sqrt(-x**2/(x**2 - y**2)) \ + - y**2*sqrt(-x**2/(x**2 - y**2))/x + + +def test_issue_3609(): + assert heurisch(1/(x * (1 + log(x)**2)), x) == atan(log(x)) + +### These are examples from the Poor Man's Integrator +### http://www-sop.inria.fr/cafe/Manuel.Bronstein/pmint/examples/ + + +def test_pmint_rat(): + # TODO: heurisch() is off by a constant: -3/4. Possibly different permutation + # would give the optimal result? + + def drop_const(expr, x): + if expr.is_Add: + return Add(*[ arg for arg in expr.args if arg.has(x) ]) + else: + return expr + + f = (x**7 - 24*x**4 - 4*x**2 + 8*x - 8)/(x**8 + 6*x**6 + 12*x**4 + 8*x**2) + g = (4 + 8*x**2 + 6*x + 3*x**3)/(x**5 + 4*x**3 + 4*x) + log(x) + + assert drop_const(ratsimp(heurisch(f, x)), x) == g + + +def test_pmint_trig(): + f = (x - tan(x)) / tan(x)**2 + tan(x) + g = -x**2/2 - x/tan(x) + log(tan(x)**2 + 1)/2 + + assert heurisch(f, x) == g + + +def test_pmint_logexp(): + f = (1 + x + x*exp(x))*(x + log(x) + exp(x) - 1)/(x + log(x) + exp(x))**2/x + g = log(x + exp(x) + log(x)) + 1/(x + exp(x) + log(x)) + + assert ratsimp(heurisch(f, x)) == g + + +def test_pmint_erf(): + f = exp(-x**2)*erf(x)/(erf(x)**3 - erf(x)**2 - erf(x) + 1) + g = sqrt(pi)*log(erf(x) - 1)/8 - sqrt(pi)*log(erf(x) + 1)/8 - sqrt(pi)/(4*erf(x) - 4) + + assert ratsimp(heurisch(f, x)) == g + + +def test_pmint_LambertW(): + f = LambertW(x) + g = x*LambertW(x) - x + x/LambertW(x) + + assert heurisch(f, x) == g + + +def test_pmint_besselj(): + f = besselj(nu + 1, x)/besselj(nu, x) + g = nu*log(x) - log(besselj(nu, x)) + + assert heurisch(f, x) == g + + f = (nu*besselj(nu, x) - x*besselj(nu + 1, x))/x + g = besselj(nu, x) + + assert heurisch(f, x) == g + + f = jn(nu + 1, x)/jn(nu, x) + g = nu*log(x) - log(jn(nu, x)) + + assert heurisch(f, x) == g + + +@slow +def test_pmint_bessel_products(): + f = x*besselj(nu, x)*bessely(nu, 2*x) + g = -2*x*besselj(nu, x)*bessely(nu - 1, 2*x)/3 + x*besselj(nu - 1, x)*bessely(nu, 2*x)/3 + + assert heurisch(f, x) == g + + f = x*besselj(nu, x)*besselk(nu, 2*x) + g = -2*x*besselj(nu, x)*besselk(nu - 1, 2*x)/5 - x*besselj(nu - 1, x)*besselk(nu, 2*x)/5 + + assert heurisch(f, x) == g + + +def test_pmint_WrightOmega(): + def omega(x): + return LambertW(exp(x)) + + f = (1 + omega(x) * (2 + cos(omega(x)) * (x + omega(x))))/(1 + omega(x))/(x + omega(x)) + g = log(x + LambertW(exp(x))) + sin(LambertW(exp(x))) + + assert heurisch(f, x) == g + + +def test_RR(): + # Make sure the algorithm does the right thing if the ring is RR. See + # issue 8685. + assert heurisch(sqrt(1 + 0.25*x**2), x, hints=[]) == \ + 0.5*x*sqrt(0.25*x**2 + 1) + 1.0*asinh(0.5*x) + +# TODO: convert the rest of PMINT tests: +# Airy functions +# f = (x - AiryAi(x)*AiryAi(1, x)) / (x**2 - AiryAi(x)**2) +# g = Rational(1,2)*ln(x + AiryAi(x)) + Rational(1,2)*ln(x - AiryAi(x)) +# f = x**2 * AiryAi(x) +# g = -AiryAi(x) + AiryAi(1, x)*x +# Whittaker functions +# f = WhittakerW(mu + 1, nu, x) / (WhittakerW(mu, nu, x) * x) +# g = x/2 - mu*ln(x) - ln(WhittakerW(mu, nu, x)) + + +def test_issue_22527(): + t, R = symbols(r't R') + z = Function('z')(t) + def f(x): + return x/sqrt(R**2 - x**2) + Uz = integrate(f(z), z) + Ut = integrate(f(t), t) + assert Ut == Uz.subs(z, t) + + +def test_heurisch_complex_erf_issue_26338(): + r = symbols('r', real=True) + a = sqrt(pi)*erf((1 + I)/2)/2 + assert integrate(exp(-I*r**2/2), (r, 0, 1)) == a - I*a + + a = exp(-x**2/(2*(2 - I)**2)) + assert heurisch(a, x, hints=[]) is None # None, not a wrong soln + a = exp(-r**2/(2*(2 - I)**2)) + assert heurisch(a, r, hints=[]) is None + a = sqrt(pi)*erf((1 + I)/2)/2 + assert integrate(exp(-I*x**2/2), (x, 0, 1)) == a - I*a + + +def test_issue_15498(): + Z0 = Function('Z0') + k01, k10, t, s= symbols('k01 k10 t s', real=True, positive=True) + m = Matrix([[exp(-k10*t)]]) + _83 = Rational(83, 100) # 0.83 works, too + [a, b, c, d, e, f, g] = [100, 0.5, _83, 50, 0.6, 2, 120] + AIF_btf = a*(d*e*(1 - exp(-(t - b)/e)) + f*g*(1 - exp(-(t - b)/g))) + AIF_atf = a*(d*e*exp(-(t - b)/e)*(exp((c - b)/e) - 1 + ) + f*g*exp(-(t - b)/g)*(exp((c - b)/g) - 1)) + AIF_sym = Piecewise((0, t < b), (AIF_btf, And(b <= t, t < c)), (AIF_atf, c <= t)) + aif_eq = Eq(Z0(t), AIF_sym) + f_vec = Matrix([[k01*Z0(t)]]) + integrand = m*m.subs(t, s)**-1*f_vec.subs(aif_eq.lhs, aif_eq.rhs).subs(t, s) + solution = integrate(integrand[0], (s, 0, t)) + assert solution is not None # does not hang and takes less than 10 s + + +@slow +def test_heurisch_issue_26930(): + integrand = x**Rational(4, 3)*log(x) + anti = 3*x**(S(7)/3)*log(x)/7 - 9*x**(S(7)/3)/49 + assert heurisch(integrand, x) == anti + assert integrate(integrand, x) == anti + assert integrate(integrand, (x, 0, 1)) == -S(9)/49 + + +def test_heurisch_issue_26922(): + + a, b, x = symbols("a, b, x", real=True, positive=True) + C = symbols("C", real=True) + i1 = -C*x*exp(-a*x**2 - sqrt(b)*x) + i2 = C*x*exp(-a*x**2 + sqrt(b)*x) + i = Integral(i1, x) + Integral(i2, x) + res = ( + -C*exp(-a*x**2)*exp(sqrt(b)*x)/(2*a) + + C*exp(-a*x**2)*exp(-sqrt(b)*x)/(2*a) + + sqrt(pi)*C*sqrt(b)*exp(b/(4*a))*erf(sqrt(a)*x - sqrt(b)/(2*sqrt(a)))/(4*a**(S(3)/2)) + + sqrt(pi)*C*sqrt(b)*exp(b/(4*a))*erf(sqrt(a)*x + sqrt(b)/(2*sqrt(a)))/(4*a**(S(3)/2)) + ) + + assert i.doit(heurisch=False).expand() == res diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_integrals.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_integrals.py new file mode 100644 index 0000000000000000000000000000000000000000..41e1ef3aa36334189f14cf734ac2ad26d001b506 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_integrals.py @@ -0,0 +1,2187 @@ +import math +from sympy.concrete.summations import (Sum, summation) +from sympy.core.add import Add +from sympy.core.containers import Tuple +from sympy.core.expr import Expr +from sympy.core.function import (Derivative, Function, Lambda, diff) +from sympy.core import EulerGamma +from sympy.core.numbers import (E, I, Rational, nan, oo, pi, zoo, all_close) +from sympy.core.relational import (Eq, Ne) +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.core.sympify import sympify +from sympy.functions.elementary.complexes import (Abs, im, polar_lift, re, sign) +from sympy.functions.elementary.exponential import (LambertW, exp, exp_polar, log) +from sympy.functions.elementary.hyperbolic import (acosh, asinh, cosh, coth, csch, sinh, tanh, sech) +from sympy.functions.elementary.miscellaneous import (Max, Min, sqrt) +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import (acos, asin, atan, cos, sin, sinc, tan, sec) +from sympy.functions.special.delta_functions import DiracDelta, Heaviside +from sympy.functions.special.error_functions import (Ci, Ei, Si, erf, erfc, erfi, fresnelc, li) +from sympy.functions.special.gamma_functions import (gamma, polygamma) +from sympy.functions.special.hyper import (hyper, meijerg) +from sympy.functions.special.singularity_functions import SingularityFunction +from sympy.functions.special.zeta_functions import lerchphi +from sympy.integrals.integrals import integrate +from sympy.logic.boolalg import And +from sympy.matrices.dense import Matrix +from sympy.polys.polytools import (Poly, factor) +from sympy.printing.str import sstr +from sympy.series.order import O +from sympy.sets.sets import Interval +from sympy.simplify.gammasimp import gammasimp +from sympy.simplify.simplify import simplify +from sympy.simplify.trigsimp import trigsimp +from sympy.tensor.indexed import (Idx, IndexedBase) +from sympy.core.expr import unchanged +from sympy.functions.elementary.integers import floor +from sympy.integrals.integrals import Integral +from sympy.integrals.risch import NonElementaryIntegral +from sympy.physics import units +from sympy.testing.pytest import raises, slow, warns_deprecated_sympy, warns +from sympy.utilities.exceptions import SymPyDeprecationWarning +from sympy.core.random import verify_numerically + + +x, y, z, a, b, c, d, e, s, t, x_1, x_2 = symbols('x y z a b c d e s t x_1 x_2') +n = Symbol('n', integer=True) +f = Function('f') + + +def NS(e, n=15, **options): + return sstr(sympify(e).evalf(n, **options), full_prec=True) + + +def test_poly_deprecated(): + p = Poly(2*x, x) + assert p.integrate(x) == Poly(x**2, x, domain='QQ') + # The stacklevel is based on Integral(Poly) + with warns(SymPyDeprecationWarning, test_stacklevel=False): + integrate(p, x) + with warns(SymPyDeprecationWarning, test_stacklevel=False): + Integral(p, (x,)) + + +@slow +def test_principal_value(): + g = 1 / x + assert Integral(g, (x, -oo, oo)).principal_value() == 0 + assert Integral(g, (y, -oo, oo)).principal_value() == oo * sign(1 / x) + raises(ValueError, lambda: Integral(g, (x)).principal_value()) + raises(ValueError, lambda: Integral(g).principal_value()) + + l = 1 / ((x ** 3) - 1) + assert Integral(l, (x, -oo, oo)).principal_value().together() == -sqrt(3)*pi/3 + raises(ValueError, lambda: Integral(l, (x, -oo, 1)).principal_value()) + + d = 1 / (x ** 2 - 1) + assert Integral(d, (x, -oo, oo)).principal_value() == 0 + assert Integral(d, (x, -2, 2)).principal_value() == -log(3) + + v = x / (x ** 2 - 1) + assert Integral(v, (x, -oo, oo)).principal_value() == 0 + assert Integral(v, (x, -2, 2)).principal_value() == 0 + + s = x ** 2 / (x ** 2 - 1) + assert Integral(s, (x, -oo, oo)).principal_value() is oo + assert Integral(s, (x, -2, 2)).principal_value() == -log(3) + 4 + + f = 1 / ((x ** 2 - 1) * (1 + x ** 2)) + assert Integral(f, (x, -oo, oo)).principal_value() == -pi / 2 + assert Integral(f, (x, -2, 2)).principal_value() == -atan(2) - log(3) / 2 + + +def diff_test(i): + """Return the set of symbols, s, which were used in testing that + i.diff(s) agrees with i.doit().diff(s). If there is an error then + the assertion will fail, causing the test to fail.""" + syms = i.free_symbols + for s in syms: + assert (i.diff(s).doit() - i.doit().diff(s)).expand() == 0 + return syms + + +def test_improper_integral(): + assert integrate(log(x), (x, 0, 1)) == -1 + assert integrate(x**(-2), (x, 1, oo)) == 1 + assert integrate(1/(1 + exp(x)), (x, 0, oo)) == log(2) + + +def test_constructor(): + # this is shared by Sum, so testing Integral's constructor + # is equivalent to testing Sum's + s1 = Integral(n, n) + assert s1.limits == (Tuple(n),) + s2 = Integral(n, (n,)) + assert s2.limits == (Tuple(n),) + s3 = Integral(Sum(x, (x, 1, y))) + assert s3.limits == (Tuple(y),) + s4 = Integral(n, Tuple(n,)) + assert s4.limits == (Tuple(n),) + + s5 = Integral(n, (n, Interval(1, 2))) + assert s5.limits == (Tuple(n, 1, 2),) + + # Testing constructor with inequalities: + s6 = Integral(n, n > 10) + assert s6.limits == (Tuple(n, 10, oo),) + s7 = Integral(n, (n > 2) & (n < 5)) + assert s7.limits == (Tuple(n, 2, 5),) + + +def test_basics(): + + assert Integral(0, x) != 0 + assert Integral(x, (x, 1, 1)) != 0 + assert Integral(oo, x) != oo + assert Integral(S.NaN, x) is S.NaN + + assert diff(Integral(y, y), x) == 0 + assert diff(Integral(x, (x, 0, 1)), x) == 0 + assert diff(Integral(x, x), x) == x + assert diff(Integral(t, (t, 0, x)), x) == x + + e = (t + 1)**2 + assert diff(integrate(e, (t, 0, x)), x) == \ + diff(Integral(e, (t, 0, x)), x).doit().expand() == \ + ((1 + x)**2).expand() + assert diff(integrate(e, (t, 0, x)), t) == \ + diff(Integral(e, (t, 0, x)), t) == 0 + assert diff(integrate(e, (t, 0, x)), a) == \ + diff(Integral(e, (t, 0, x)), a) == 0 + assert diff(integrate(e, t), a) == diff(Integral(e, t), a) == 0 + + assert integrate(e, (t, a, x)).diff(x) == \ + Integral(e, (t, a, x)).diff(x).doit().expand() + assert Integral(e, (t, a, x)).diff(x).doit() == ((1 + x)**2) + assert integrate(e, (t, x, a)).diff(x).doit() == (-(1 + x)**2).expand() + + assert integrate(t**2, (t, x, 2*x)).diff(x) == 7*x**2 + + assert Integral(x, x).atoms() == {x} + assert Integral(f(x), (x, 0, 1)).atoms() == {S.Zero, S.One, x} + + assert diff_test(Integral(x, (x, 3*y))) == {y} + assert diff_test(Integral(x, (a, 3*y))) == {x, y} + + assert integrate(x, (x, oo, oo)) == 0 #issue 8171 + assert integrate(x, (x, -oo, -oo)) == 0 + + # sum integral of terms + assert integrate(y + x + exp(x), x) == x*y + x**2/2 + exp(x) + + assert Integral(x).is_commutative + n = Symbol('n', commutative=False) + assert Integral(n + x, x).is_commutative is False + + +def test_diff_wrt(): + class Test(Expr): + _diff_wrt = True + is_commutative = True + + t = Test() + assert integrate(t + 1, t) == t**2/2 + t + assert integrate(t + 1, (t, 0, 1)) == Rational(3, 2) + + raises(ValueError, lambda: integrate(x + 1, x + 1)) + raises(ValueError, lambda: integrate(x + 1, (x + 1, 0, 1))) + + +def test_basics_multiple(): + assert diff_test(Integral(x, (x, 3*x, 5*y), (y, x, 2*x))) == {x} + assert diff_test(Integral(x, (x, 5*y), (y, x, 2*x))) == {x} + assert diff_test(Integral(x, (x, 5*y), (y, y, 2*x))) == {x, y} + assert diff_test(Integral(y, y, x)) == {x, y} + assert diff_test(Integral(y*x, x, y)) == {x, y} + assert diff_test(Integral(x + y, y, (y, 1, x))) == {x} + assert diff_test(Integral(x + y, (x, x, y), (y, y, x))) == {x, y} + + +def test_conjugate_transpose(): + A, B = symbols("A B", commutative=False) + + x = Symbol("x", complex=True) + p = Integral(A*B, (x,)) + assert p.adjoint().doit() == p.doit().adjoint() + assert p.conjugate().doit() == p.doit().conjugate() + assert p.transpose().doit() == p.doit().transpose() + + x = Symbol("x", real=True) + p = Integral(A*B, (x,)) + assert p.adjoint().doit() == p.doit().adjoint() + assert p.conjugate().doit() == p.doit().conjugate() + assert p.transpose().doit() == p.doit().transpose() + + +def test_integration(): + assert integrate(0, (t, 0, x)) == 0 + assert integrate(3, (t, 0, x)) == 3*x + assert integrate(t, (t, 0, x)) == x**2/2 + assert integrate(3*t, (t, 0, x)) == 3*x**2/2 + assert integrate(3*t**2, (t, 0, x)) == x**3 + assert integrate(1/t, (t, 1, x)) == log(x) + assert integrate(-1/t**2, (t, 1, x)) == 1/x - 1 + assert integrate(t**2 + 5*t - 8, (t, 0, x)) == x**3/3 + 5*x**2/2 - 8*x + assert integrate(x**2, x) == x**3/3 + assert integrate((3*t*x)**5, x) == (3*t)**5 * x**6 / 6 + + b = Symbol("b") + c = Symbol("c") + assert integrate(a*t, (t, 0, x)) == a*x**2/2 + assert integrate(a*t**4, (t, 0, x)) == a*x**5/5 + assert integrate(a*t**2 + b*t + c, (t, 0, x)) == a*x**3/3 + b*x**2/2 + c*x + + +def test_multiple_integration(): + assert integrate((x**2)*(y**2), (x, 0, 1), (y, -1, 2)) == Rational(1) + assert integrate((y**2)*(x**2), x, y) == Rational(1, 9)*(x**3)*(y**3) + assert integrate(1/(x + 3)/(1 + x)**3, x) == \ + log(3 + x)*Rational(-1, 8) + log(1 + x)*Rational(1, 8) + x/(4 + 8*x + 4*x**2) + assert integrate(sin(x*y)*y, (x, 0, 1), (y, 0, 1)) == -sin(1) + 1 + + +def test_issue_3532(): + assert integrate(exp(-x), (x, 0, oo)) == 1 + + +def test_issue_3560(): + assert integrate(sqrt(x)**3, x) == 2*sqrt(x)**5/5 + assert integrate(sqrt(x), x) == 2*sqrt(x)**3/3 + assert integrate(1/sqrt(x)**3, x) == -2/sqrt(x) + + +def test_issue_18038(): + raises(AttributeError, lambda: integrate((x, x))) + + +def test_integrate_poly(): + p = Poly(x + x**2*y + y**3, x, y) + + # The stacklevel is based on Integral(Poly) + with warns_deprecated_sympy(): + qx = Integral(p, x) + with warns(SymPyDeprecationWarning, test_stacklevel=False): + qx = integrate(p, x) + with warns(SymPyDeprecationWarning, test_stacklevel=False): + qy = integrate(p, y) + + assert isinstance(qx, Poly) is True + assert isinstance(qy, Poly) is True + + assert qx.gens == (x, y) + assert qy.gens == (x, y) + + assert qx.as_expr() == x**2/2 + x**3*y/3 + x*y**3 + assert qy.as_expr() == x*y + x**2*y**2/2 + y**4/4 + + +def test_integrate_poly_definite(): + p = Poly(x + x**2*y + y**3, x, y) + + with warns_deprecated_sympy(): + Qx = Integral(p, (x, 0, 1)) + with warns(SymPyDeprecationWarning, test_stacklevel=False): + Qx = integrate(p, (x, 0, 1)) + with warns(SymPyDeprecationWarning, test_stacklevel=False): + Qy = integrate(p, (y, 0, pi)) + + assert isinstance(Qx, Poly) is True + assert isinstance(Qy, Poly) is True + + assert Qx.gens == (y,) + assert Qy.gens == (x,) + + assert Qx.as_expr() == S.Half + y/3 + y**3 + assert Qy.as_expr() == pi**4/4 + pi*x + pi**2*x**2/2 + + +def test_integrate_omit_var(): + y = Symbol('y') + + assert integrate(x) == x**2/2 + + raises(ValueError, lambda: integrate(2)) + raises(ValueError, lambda: integrate(x*y)) + + +def test_integrate_poly_accurately(): + y = Symbol('y') + assert integrate(x*sin(y), x) == x**2*sin(y)/2 + + # when passed to risch_norman, this will be a CPU hog, so this really + # checks, that integrated function is recognized as polynomial + assert integrate(x**1000*sin(y), x) == x**1001*sin(y)/1001 + + +def test_issue_3635(): + y = Symbol('y') + assert integrate(x**2, y) == x**2*y + assert integrate(x**2, (y, -1, 1)) == 2*x**2 + +# works in SymPy and py.test but hangs in `setup.py test` + + +def test_integrate_linearterm_pow(): + # check integrate((a*x+b)^c, x) -- issue 3499 + y = Symbol('y', positive=True) + # TODO: Remove conds='none' below, let the assumption take care of it. + assert integrate(x**y, x, conds='none') == x**(y + 1)/(y + 1) + assert integrate((exp(y)*x + 1/y)**(1 + sin(y)), x, conds='none') == \ + exp(-y)*(exp(y)*x + 1/y)**(2 + sin(y)) / (2 + sin(y)) + + +def test_issue_3618(): + assert integrate(pi*sqrt(x), x) == 2*pi*sqrt(x)**3/3 + assert integrate(pi*sqrt(x) + E*sqrt(x)**3, x) == \ + 2*pi*sqrt(x)**3/3 + 2*E *sqrt(x)**5/5 + + +def test_issue_3623(): + assert integrate(cos((n + 1)*x), x) == Piecewise( + (sin(x*(n + 1))/(n + 1), Ne(n + 1, 0)), (x, True)) + assert integrate(cos((n - 1)*x), x) == Piecewise( + (sin(x*(n - 1))/(n - 1), Ne(n - 1, 0)), (x, True)) + assert integrate(cos((n + 1)*x) + cos((n - 1)*x), x) == \ + Piecewise((sin(x*(n - 1))/(n - 1), Ne(n - 1, 0)), (x, True)) + \ + Piecewise((sin(x*(n + 1))/(n + 1), Ne(n + 1, 0)), (x, True)) + + +def test_issue_3664(): + n = Symbol('n', integer=True, nonzero=True) + assert integrate(-1./2 * x * sin(n * pi * x/2), [x, -2, 0]) == \ + 2.0*cos(pi*n)/(pi*n) + assert integrate(x * sin(n * pi * x/2) * Rational(-1, 2), [x, -2, 0]) == \ + 2*cos(pi*n)/(pi*n) + + +def test_issue_3679(): + # definite integration of rational functions gives wrong answers + assert NS(Integral(1/(x**2 - 8*x + 17), (x, 2, 4))) == '1.10714871779409' + + +def test_issue_3686(): # remove this when fresnel integrals are implemented + from sympy.core.function import expand_func + from sympy.functions.special.error_functions import fresnels + assert expand_func(integrate(sin(x**2), x)) == \ + sqrt(2)*sqrt(pi)*fresnels(sqrt(2)*x/sqrt(pi))/2 + + +def test_integrate_units(): + m = units.m + s = units.s + assert integrate(x * m/s, (x, 1*s, 5*s)) == 12*m*s + + +def test_transcendental_functions(): + assert integrate(LambertW(2*x), x) == \ + -x + x*LambertW(2*x) + x/LambertW(2*x) + + +def test_log_polylog(): + assert integrate(log(1 - x)/x, (x, 0, 1)) == -pi**2/6 + assert integrate(log(x)*(1 - x)**(-1), (x, 0, 1)) == -pi**2/6 + + +def test_issue_3740(): + f = 4*log(x) - 2*log(x)**2 + fid = diff(integrate(f, x), x) + assert abs(f.subs(x, 42).evalf() - fid.subs(x, 42).evalf()) < 1e-10 + + +def test_issue_3788(): + assert integrate(1/(1 + x**2), x) == atan(x) + + +def test_issue_3952(): + f = sin(x) + assert integrate(f, x) == -cos(x) + raises(ValueError, lambda: integrate(f, 2*x)) + + +def test_issue_4516(): + assert integrate(2**x - 2*x, x) == 2**x/log(2) - x**2 + + +def test_issue_7450(): + ans = integrate(exp(-(1 + I)*x), (x, 0, oo)) + assert re(ans) == S.Half and im(ans) == Rational(-1, 2) + + +def test_issue_8623(): + assert integrate((1 + cos(2*x)) / (3 - 2*cos(2*x)), (x, 0, pi)) == -pi/2 + sqrt(5)*pi/2 + assert integrate((1 + cos(2*x))/(3 - 2*cos(2*x))) == -x/2 + sqrt(5)*(atan(sqrt(5)*tan(x)) + \ + pi*floor((x - pi/2)/pi))/2 + + +def test_issue_9569(): + assert integrate(1 / (2 - cos(x)), (x, 0, pi)) == pi/sqrt(3) + assert integrate(1/(2 - cos(x))) == 2*sqrt(3)*(atan(sqrt(3)*tan(x/2)) + pi*floor((x/2 - pi/2)/pi))/3 + + +def test_issue_13733(): + s = Symbol('s', positive=True) + pz = exp(-(z - y)**2/(2*s*s))/sqrt(2*pi*s*s) + pzgx = integrate(pz, (z, x, oo)) + assert integrate(pzgx, (x, 0, oo)) == sqrt(2)*s*exp(-y**2/(2*s**2))/(2*sqrt(pi)) + \ + y*erf(sqrt(2)*y/(2*s))/2 + y/2 + + +def test_issue_13749(): + assert integrate(1 / (2 + cos(x)), (x, 0, pi)) == pi/sqrt(3) + assert integrate(1/(2 + cos(x))) == 2*sqrt(3)*(atan(sqrt(3)*tan(x/2)/3) + pi*floor((x/2 - pi/2)/pi))/3 + + +def test_issue_18133(): + assert integrate(exp(x)/(1 + x)**2, x) == NonElementaryIntegral(exp(x)/(x + 1)**2, x) + + +def test_issue_21741(): + a = 4e6 + b = 2.5e-7 + r = Piecewise((b*I*exp(-a*I*pi*t*y)*exp(-a*I*pi*x*z)/(pi*x), Ne(x, 0)), + (z*exp(-a*I*pi*t*y), True)) + fun = E**((-2*I*pi*(z*x+t*y))/(500*10**(-9))) + assert all_close(integrate(fun, z), r) + + +def test_matrices(): + M = Matrix(2, 2, lambda i, j: (i + j + 1)*sin((i + j + 1)*x)) + + assert integrate(M, x) == Matrix([ + [-cos(x), -cos(2*x)], + [-cos(2*x), -cos(3*x)], + ]) + + +def test_integrate_functions(): + # issue 4111 + assert integrate(f(x), x) == Integral(f(x), x) + assert integrate(f(x), (x, 0, 1)) == Integral(f(x), (x, 0, 1)) + assert integrate(f(x)*diff(f(x), x), x) == f(x)**2/2 + assert integrate(diff(f(x), x) / f(x), x) == log(f(x)) + + +def test_integrate_derivatives(): + assert integrate(Derivative(f(x), x), x) == f(x) + assert integrate(Derivative(f(y), y), x) == x*Derivative(f(y), y) + assert integrate(Derivative(f(x), x)**2, x) == \ + Integral(Derivative(f(x), x)**2, x) + + +def test_transform(): + a = Integral(x**2 + 1, (x, -1, 2)) + fx = x + fy = 3*y + 1 + assert a.doit() == a.transform(fx, fy).doit() + assert a.transform(fx, fy).transform(fy, fx) == a + fx = 3*x + 1 + fy = y + assert a.transform(fx, fy).transform(fy, fx) == a + a = Integral(sin(1/x), (x, 0, 1)) + assert a.transform(x, 1/y) == Integral(sin(y)/y**2, (y, 1, oo)) + assert a.transform(x, 1/y).transform(y, 1/x) == a + a = Integral(exp(-x**2), (x, -oo, oo)) + assert a.transform(x, 2*y) == Integral(2*exp(-4*y**2), (y, -oo, oo)) + # < 3 arg limit handled properly + assert Integral(x, x).transform(x, a*y).doit() == \ + Integral(y*a**2, y).doit() + _3 = S(3) + assert Integral(x, (x, 0, -_3)).transform(x, 1/y).doit() == \ + Integral(-1/x**3, (x, -oo, -1/_3)).doit() + assert Integral(x, (x, 0, _3)).transform(x, 1/y) == \ + Integral(y**(-3), (y, 1/_3, oo)) + # issue 8400 + i = Integral(x + y, (x, 1, 2), (y, 1, 2)) + assert i.transform(x, (x + 2*y, x)).doit() == \ + i.transform(x, (x + 2*z, x)).doit() == 3 + + i = Integral(x, (x, a, b)) + assert i.transform(x, 2*s) == Integral(4*s, (s, a/2, b/2)) + raises(ValueError, lambda: i.transform(x, 1)) + raises(ValueError, lambda: i.transform(x, s*t)) + raises(ValueError, lambda: i.transform(x, -s)) + raises(ValueError, lambda: i.transform(x, (s, t))) + raises(ValueError, lambda: i.transform(2*x, 2*s)) + + i = Integral(x**2, (x, 1, 2)) + raises(ValueError, lambda: i.transform(x**2, s)) + + am = Symbol('a', negative=True) + bp = Symbol('b', positive=True) + i = Integral(x, (x, bp, am)) + i.transform(x, 2*s) + assert i.transform(x, 2*s) == Integral(-4*s, (s, am/2, bp/2)) + + i = Integral(x, (x, a)) + assert i.transform(x, 2*s) == Integral(4*s, (s, a/2)) + + +def test_issue_4052(): + f = S.Half*asin(x) + x*sqrt(1 - x**2)/2 + + assert integrate(cos(asin(x)), x) == f + assert integrate(sin(acos(x)), x) == f + + +@slow +def test_evalf_integrals(): + assert NS(Integral(x, (x, 2, 5)), 15) == '10.5000000000000' + gauss = Integral(exp(-x**2), (x, -oo, oo)) + assert NS(gauss, 15) == '1.77245385090552' + assert NS(gauss**2 - pi + E*Rational( + 1, 10**20), 15) in ('2.71828182845904e-20', '2.71828182845905e-20') + # A monster of an integral from http://mathworld.wolfram.com/DefiniteIntegral.html + t = Symbol('t') + a = 8*sqrt(3)/(1 + 3*t**2) + b = 16*sqrt(2)*(3*t + 1)*sqrt(4*t**2 + t + 1)**3 + c = (3*t**2 + 1)*(11*t**2 + 2*t + 3)**2 + d = sqrt(2)*(249*t**2 + 54*t + 65)/(11*t**2 + 2*t + 3)**2 + f = a - b/c - d + assert NS(Integral(f, (t, 0, 1)), 50) == \ + NS((3*sqrt(2) - 49*pi + 162*atan(sqrt(2)))/12, 50) + # http://mathworld.wolfram.com/VardisIntegral.html + assert NS(Integral(log(log(1/x))/(1 + x + x**2), (x, 0, 1)), 15) == \ + NS('pi/sqrt(3) * log(2*pi**(5/6) / gamma(1/6))', 15) + # http://mathworld.wolfram.com/AhmedsIntegral.html + assert NS(Integral(atan(sqrt(x**2 + 2))/(sqrt(x**2 + 2)*(x**2 + 1)), (x, + 0, 1)), 15) == NS(5*pi**2/96, 15) + # http://mathworld.wolfram.com/AbelsIntegral.html + assert NS(Integral(x/((exp(pi*x) - exp( + -pi*x))*(x**2 + 1)), (x, 0, oo)), 15) == NS('log(2)/2-1/4', 15) + # Complex part trimming + # http://mathworld.wolfram.com/VardisIntegral.html + assert NS(Integral(log(log(sin(x)/cos(x))), (x, pi/4, pi/2)), 15, chop=True) == \ + NS('pi/4*log(4*pi**3/gamma(1/4)**4)', 15) + # + # Endpoints causing trouble (rounding error in integration points -> complex log) + assert NS( + 2 + Integral(log(2*cos(x/2)), (x, -pi, pi)), 17, chop=True) == NS(2, 17) + assert NS( + 2 + Integral(log(2*cos(x/2)), (x, -pi, pi)), 20, chop=True) == NS(2, 20) + assert NS( + 2 + Integral(log(2*cos(x/2)), (x, -pi, pi)), 22, chop=True) == NS(2, 22) + # Needs zero handling + assert NS(pi - 4*Integral( + 'sqrt(1-x**2)', (x, 0, 1)), 15, maxn=30, chop=True) in ('0.0', '0') + # Oscillatory quadrature + a = Integral(sin(x)/x**2, (x, 1, oo)).evalf(maxn=15) + assert 0.49 < a < 0.51 + assert NS( + Integral(sin(x)/x**2, (x, 1, oo)), quad='osc') == '0.504067061906928' + assert NS(Integral( + cos(pi*x + 1)/x, (x, -oo, -1)), quad='osc') == '0.276374705640365' + # indefinite integrals aren't evaluated + assert NS(Integral(x, x)) == 'Integral(x, x)' + assert NS(Integral(x, (x, y))) == 'Integral(x, (x, y))' + + +def test_evalf_issue_939(): + # https://github.com/sympy/sympy/issues/4038 + + # The output form of an integral may differ by a step function between + # revisions, making this test a bit useless. This can't be said about + # other two tests. For now, all values of this evaluation are used here, + # but in future this should be reconsidered. + assert NS(integrate(1/(x**5 + 1), x).subs(x, 4), chop=True) in \ + ['-0.000976138910649103', '0.965906660135753', '1.93278945918216'] + + assert NS(Integral(1/(x**5 + 1), (x, 2, 4))) == '0.0144361088886740' + assert NS( + integrate(1/(x**5 + 1), (x, 2, 4)), chop=True) == '0.0144361088886740' + + +def test_double_previously_failing_integrals(): + # Double integrals not implemented <- Sure it is! + res = integrate(sqrt(x) + x*y, (x, 1, 2), (y, -1, 1)) + # Old numerical test + assert NS(res, 15) == '2.43790283299492' + # Symbolic test + assert res == Rational(-4, 3) + 8*sqrt(2)/3 + # double integral + zero detection + assert integrate(sin(x + x*y), (x, -1, 1), (y, -1, 1)) is S.Zero + + +def test_integrate_SingularityFunction(): + in_1 = SingularityFunction(x, a, 3) + SingularityFunction(x, 5, -1) + out_1 = SingularityFunction(x, a, 4)/4 + SingularityFunction(x, 5, 0) + assert integrate(in_1, x) == out_1 + + in_2 = 10*SingularityFunction(x, 4, 0) - 5*SingularityFunction(x, -6, -2) + out_2 = 10*SingularityFunction(x, 4, 1) - 5*SingularityFunction(x, -6, -1) + assert integrate(in_2, x) == out_2 + + in_3 = 2*x**2*y -10*SingularityFunction(x, -4, 7) - 2*SingularityFunction(y, 10, -2) + out_3_1 = 2*x**3*y/3 - 2*x*SingularityFunction(y, 10, -2) - 5*SingularityFunction(x, -4, 8)/4 + out_3_2 = x**2*y**2 - 10*y*SingularityFunction(x, -4, 7) - 2*SingularityFunction(y, 10, -1) + assert integrate(in_3, x) == out_3_1 + assert integrate(in_3, y) == out_3_2 + + assert unchanged(Integral, in_3, (x,)) + assert Integral(in_3, x) == Integral(in_3, (x,)) + assert Integral(in_3, x).doit() == out_3_1 + + in_4 = 10*SingularityFunction(x, -4, 7) - 2*SingularityFunction(x, 10, -2) + out_4 = 5*SingularityFunction(x, -4, 8)/4 - 2*SingularityFunction(x, 10, -1) + assert integrate(in_4, (x, -oo, x)) == out_4 + + assert integrate(SingularityFunction(x, 5, -1), x) == SingularityFunction(x, 5, 0) + assert integrate(SingularityFunction(x, 0, -1), (x, -oo, oo)) == 1 + assert integrate(5*SingularityFunction(x, 5, -1), (x, -oo, oo)) == 5 + assert integrate(SingularityFunction(x, 5, -1) * f(x), (x, -oo, oo)) == f(5) + + +def test_integrate_DiracDelta(): + # This is here to check that deltaintegrate is being called, but also + # to test definite integrals. More tests are in test_deltafunctions.py + assert integrate(DiracDelta(x) * f(x), (x, -oo, oo)) == f(0) + assert integrate(DiracDelta(x)**2, (x, -oo, oo)) == DiracDelta(0) + # issue 4522 + assert integrate(integrate((4 - 4*x + x*y - 4*y) * \ + DiracDelta(x)*DiracDelta(y - 1), (x, 0, 1)), (y, 0, 1)) == 0 + # issue 5729 + p = exp(-(x**2 + y**2))/pi + assert integrate(p*DiracDelta(x - 10*y), (x, -oo, oo), (y, -oo, oo)) == \ + integrate(p*DiracDelta(x - 10*y), (y, -oo, oo), (x, -oo, oo)) == \ + integrate(p*DiracDelta(10*x - y), (x, -oo, oo), (y, -oo, oo)) == \ + integrate(p*DiracDelta(10*x - y), (y, -oo, oo), (x, -oo, oo)) == \ + 1/sqrt(101*pi) + + +def test_integrate_returns_piecewise(): + assert integrate(x**y, x) == Piecewise( + (x**(y + 1)/(y + 1), Ne(y, -1)), (log(x), True)) + assert integrate(x**y, y) == Piecewise( + (x**y/log(x), Ne(log(x), 0)), (y, True)) + assert integrate(exp(n*x), x) == Piecewise( + (exp(n*x)/n, Ne(n, 0)), (x, True)) + assert integrate(x*exp(n*x), x) == Piecewise( + ((n*x - 1)*exp(n*x)/n**2, Ne(n**2, 0)), (x**2/2, True)) + assert integrate(x**(n*y), x) == Piecewise( + (x**(n*y + 1)/(n*y + 1), Ne(n*y, -1)), (log(x), True)) + assert integrate(x**(n*y), y) == Piecewise( + (x**(n*y)/(n*log(x)), Ne(n*log(x), 0)), (y, True)) + assert integrate(cos(n*x), x) == Piecewise( + (sin(n*x)/n, Ne(n, 0)), (x, True)) + assert integrate(cos(n*x)**2, x) == Piecewise( + ((n*x/2 + sin(n*x)*cos(n*x)/2)/n, Ne(n, 0)), (x, True)) + assert integrate(x*cos(n*x), x) == Piecewise( + (x*sin(n*x)/n + cos(n*x)/n**2, Ne(n, 0)), (x**2/2, True)) + assert integrate(sin(n*x), x) == Piecewise( + (-cos(n*x)/n, Ne(n, 0)), (0, True)) + assert integrate(sin(n*x)**2, x) == Piecewise( + ((n*x/2 - sin(n*x)*cos(n*x)/2)/n, Ne(n, 0)), (0, True)) + assert integrate(x*sin(n*x), x) == Piecewise( + (-x*cos(n*x)/n + sin(n*x)/n**2, Ne(n, 0)), (0, True)) + assert integrate(exp(x*y), (x, 0, z)) == Piecewise( + (exp(y*z)/y - 1/y, (y > -oo) & (y < oo) & Ne(y, 0)), (z, True)) + # https://github.com/sympy/sympy/issues/23707 + assert integrate(exp(t)*exp(-t*sqrt(x - y)), t) == Piecewise( + (-exp(t)/(sqrt(x - y)*exp(t*sqrt(x - y)) - exp(t*sqrt(x - y))), + Ne(x, y + 1)), (t, True)) + + +def test_integrate_max_min(): + x = symbols('x', real=True) + assert integrate(Min(x, 2), (x, 0, 3)) == 4 + assert integrate(Max(x**2, x**3), (x, 0, 2)) == Rational(49, 12) + assert integrate(Min(exp(x), exp(-x))**2, x) == Piecewise( \ + (exp(2*x)/2, x <= 0), (1 - exp(-2*x)/2, True)) + # issue 7907 + c = symbols('c', extended_real=True) + int1 = integrate(Max(c, x)*exp(-x**2), (x, -oo, oo)) + int2 = integrate(c*exp(-x**2), (x, -oo, c)) + int3 = integrate(x*exp(-x**2), (x, c, oo)) + assert int1 == int2 + int3 == sqrt(pi)*c*erf(c)/2 + \ + sqrt(pi)*c/2 + exp(-c**2)/2 + + +def test_integrate_Abs_sign(): + assert integrate(Abs(x), (x, -2, 1)) == Rational(5, 2) + assert integrate(Abs(x), (x, 0, 1)) == S.Half + assert integrate(Abs(x + 1), (x, 0, 1)) == Rational(3, 2) + assert integrate(Abs(x**2 - 1), (x, -2, 2)) == 4 + assert integrate(Abs(x**2 - 3*x), (x, -15, 15)) == 2259 + assert integrate(sign(x), (x, -1, 2)) == 1 + assert integrate(sign(x)*sin(x), (x, -pi, pi)) == 4 + assert integrate(sign(x - 2) * x**2, (x, 0, 3)) == Rational(11, 3) + + t, s = symbols('t s', real=True) + assert integrate(Abs(t), t) == Piecewise( + (-t**2/2, t <= 0), (t**2/2, True)) + assert integrate(Abs(2*t - 6), t) == Piecewise( + (-t**2 + 6*t, t <= 3), (t**2 - 6*t + 18, True)) + assert (integrate(abs(t - s**2), (t, 0, 2)) == + 2*s**2*Min(2, s**2) - 2*s**2 - Min(2, s**2)**2 + 2) + assert integrate(exp(-Abs(t)), t) == Piecewise( + (exp(t), t <= 0), (2 - exp(-t), True)) + assert integrate(sign(2*t - 6), t) == Piecewise( + (-t, t < 3), (t - 6, True)) + assert integrate(2*t*sign(t**2 - 1), t) == Piecewise( + (t**2, t < -1), (-t**2 + 2, t < 1), (t**2, True)) + assert integrate(sign(t), (t, s + 1)) == Piecewise( + (s + 1, s + 1 > 0), (-s - 1, s + 1 < 0), (0, True)) + + +def test_subs1(): + e = Integral(exp(x - y), x) + assert e.subs(y, 3) == Integral(exp(x - 3), x) + e = Integral(exp(x - y), (x, 0, 1)) + assert e.subs(y, 3) == Integral(exp(x - 3), (x, 0, 1)) + f = Lambda(x, exp(-x**2)) + conv = Integral(f(x - y)*f(y), (y, -oo, oo)) + assert conv.subs({x: 0}) == Integral(exp(-2*y**2), (y, -oo, oo)) + + +def test_subs2(): + e = Integral(exp(x - y), x, t) + assert e.subs(y, 3) == Integral(exp(x - 3), x, t) + e = Integral(exp(x - y), (x, 0, 1), (t, 0, 1)) + assert e.subs(y, 3) == Integral(exp(x - 3), (x, 0, 1), (t, 0, 1)) + f = Lambda(x, exp(-x**2)) + conv = Integral(f(x - y)*f(y), (y, -oo, oo), (t, 0, 1)) + assert conv.subs({x: 0}) == Integral(exp(-2*y**2), (y, -oo, oo), (t, 0, 1)) + + +def test_subs3(): + e = Integral(exp(x - y), (x, 0, y), (t, y, 1)) + assert e.subs(y, 3) == Integral(exp(x - 3), (x, 0, 3), (t, 3, 1)) + f = Lambda(x, exp(-x**2)) + conv = Integral(f(x - y)*f(y), (y, -oo, oo), (t, x, 1)) + assert conv.subs({x: 0}) == Integral(exp(-2*y**2), (y, -oo, oo), (t, 0, 1)) + + +def test_subs4(): + e = Integral(exp(x), (x, 0, y), (t, y, 1)) + assert e.subs(y, 3) == Integral(exp(x), (x, 0, 3), (t, 3, 1)) + f = Lambda(x, exp(-x**2)) + conv = Integral(f(y)*f(y), (y, -oo, oo), (t, x, 1)) + assert conv.subs({x: 0}) == Integral(exp(-2*y**2), (y, -oo, oo), (t, 0, 1)) + + +def test_subs5(): + e = Integral(exp(-x**2), (x, -oo, oo)) + assert e.subs(x, 5) == e + e = Integral(exp(-x**2 + y), x) + assert e.subs(y, 5) == Integral(exp(-x**2 + 5), x) + e = Integral(exp(-x**2 + y), (x, x)) + assert e.subs(x, 5) == Integral(exp(y - x**2), (x, 5)) + assert e.subs(y, 5) == Integral(exp(-x**2 + 5), x) + e = Integral(exp(-x**2 + y), (y, -oo, oo), (x, -oo, oo)) + assert e.subs(x, 5) == e + assert e.subs(y, 5) == e + # Test evaluation of antiderivatives + e = Integral(exp(-x**2), (x, x)) + assert e.subs(x, 5) == Integral(exp(-x**2), (x, 5)) + e = Integral(exp(x), x) + assert (e.subs(x,1) - e.subs(x,0) - Integral(exp(x), (x, 0, 1)) + ).doit().is_zero + + +def test_subs6(): + a, b = symbols('a b') + e = Integral(x*y, (x, f(x), f(y))) + assert e.subs(x, 1) == Integral(x*y, (x, f(1), f(y))) + assert e.subs(y, 1) == Integral(x, (x, f(x), f(1))) + e = Integral(x*y, (x, f(x), f(y)), (y, f(x), f(y))) + assert e.subs(x, 1) == Integral(x*y, (x, f(1), f(y)), (y, f(1), f(y))) + assert e.subs(y, 1) == Integral(x*y, (x, f(x), f(y)), (y, f(x), f(1))) + e = Integral(x*y, (x, f(x), f(a)), (y, f(x), f(a))) + assert e.subs(a, 1) == Integral(x*y, (x, f(x), f(1)), (y, f(x), f(1))) + + +def test_subs7(): + e = Integral(x, (x, 1, y), (y, 1, 2)) + assert e.subs({x: 1, y: 2}) == e + e = Integral(sin(x) + sin(y), (x, sin(x), sin(y)), + (y, 1, 2)) + assert e.subs(sin(y), 1) == e + assert e.subs(sin(x), 1) == Integral(sin(x) + sin(y), (x, 1, sin(y)), + (y, 1, 2)) + +def test_expand(): + e = Integral(f(x)+f(x**2), (x, 1, y)) + assert e.expand() == Integral(f(x), (x, 1, y)) + Integral(f(x**2), (x, 1, y)) + e = Integral(f(x)+f(x**2), (x, 1, oo)) + assert e.expand() == e + assert e.expand(force=True) == Integral(f(x), (x, 1, oo)) + \ + Integral(f(x**2), (x, 1, oo)) + + +def test_integration_variable(): + raises(ValueError, lambda: Integral(exp(-x**2), 3)) + raises(ValueError, lambda: Integral(exp(-x**2), (3, -oo, oo))) + + +def test_expand_integral(): + assert Integral(cos(x**2)*(sin(x**2) + 1), (x, 0, 1)).expand() == \ + Integral(cos(x**2)*sin(x**2), (x, 0, 1)) + \ + Integral(cos(x**2), (x, 0, 1)) + assert Integral(cos(x**2)*(sin(x**2) + 1), x).expand() == \ + Integral(cos(x**2)*sin(x**2), x) + \ + Integral(cos(x**2), x) + + +def test_as_sum_midpoint1(): + e = Integral(sqrt(x**3 + 1), (x, 2, 10)) + assert e.as_sum(1, method="midpoint") == 8*sqrt(217) + assert e.as_sum(2, method="midpoint") == 4*sqrt(65) + 12*sqrt(57) + assert e.as_sum(3, method="midpoint") == 8*sqrt(217)/3 + \ + 8*sqrt(3081)/27 + 8*sqrt(52809)/27 + assert e.as_sum(4, method="midpoint") == 2*sqrt(730) + \ + 4*sqrt(7) + 4*sqrt(86) + 6*sqrt(14) + assert abs(e.as_sum(4, method="midpoint").n() - e.n()) < 0.5 + + e = Integral(sqrt(x**3 + y**3), (x, 2, 10), (y, 0, 10)) + raises(NotImplementedError, lambda: e.as_sum(4)) + + +def test_as_sum_midpoint2(): + e = Integral((x + y)**2, (x, 0, 1)) + n = Symbol('n', positive=True, integer=True) + assert e.as_sum(1, method="midpoint").expand() == Rational(1, 4) + y + y**2 + assert e.as_sum(2, method="midpoint").expand() == Rational(5, 16) + y + y**2 + assert e.as_sum(3, method="midpoint").expand() == Rational(35, 108) + y + y**2 + assert e.as_sum(4, method="midpoint").expand() == Rational(21, 64) + y + y**2 + assert e.as_sum(n, method="midpoint").expand() == \ + y**2 + y + Rational(1, 3) - 1/(12*n**2) + + +def test_as_sum_left(): + e = Integral((x + y)**2, (x, 0, 1)) + assert e.as_sum(1, method="left").expand() == y**2 + assert e.as_sum(2, method="left").expand() == Rational(1, 8) + y/2 + y**2 + assert e.as_sum(3, method="left").expand() == Rational(5, 27) + y*Rational(2, 3) + y**2 + assert e.as_sum(4, method="left").expand() == Rational(7, 32) + y*Rational(3, 4) + y**2 + assert e.as_sum(n, method="left").expand() == \ + y**2 + y + Rational(1, 3) - y/n - 1/(2*n) + 1/(6*n**2) + assert e.as_sum(10, method="left", evaluate=False).has(Sum) + + +def test_as_sum_right(): + e = Integral((x + y)**2, (x, 0, 1)) + assert e.as_sum(1, method="right").expand() == 1 + 2*y + y**2 + assert e.as_sum(2, method="right").expand() == Rational(5, 8) + y*Rational(3, 2) + y**2 + assert e.as_sum(3, method="right").expand() == Rational(14, 27) + y*Rational(4, 3) + y**2 + assert e.as_sum(4, method="right").expand() == Rational(15, 32) + y*Rational(5, 4) + y**2 + assert e.as_sum(n, method="right").expand() == \ + y**2 + y + Rational(1, 3) + y/n + 1/(2*n) + 1/(6*n**2) + + +def test_as_sum_trapezoid(): + e = Integral((x + y)**2, (x, 0, 1)) + assert e.as_sum(1, method="trapezoid").expand() == y**2 + y + S.Half + assert e.as_sum(2, method="trapezoid").expand() == y**2 + y + Rational(3, 8) + assert e.as_sum(3, method="trapezoid").expand() == y**2 + y + Rational(19, 54) + assert e.as_sum(4, method="trapezoid").expand() == y**2 + y + Rational(11, 32) + assert e.as_sum(n, method="trapezoid").expand() == \ + y**2 + y + Rational(1, 3) + 1/(6*n**2) + assert Integral(sign(x), (x, 0, 1)).as_sum(1, 'trapezoid') == S.Half + + +def test_as_sum_raises(): + e = Integral((x + y)**2, (x, 0, 1)) + raises(ValueError, lambda: e.as_sum(-1)) + raises(ValueError, lambda: e.as_sum(0)) + raises(ValueError, lambda: Integral(x).as_sum(3)) + raises(ValueError, lambda: e.as_sum(oo)) + raises(ValueError, lambda: e.as_sum(3, method='xxxx2')) + + +def test_nested_doit(): + e = Integral(Integral(x, x), x) + f = Integral(x, x, x) + assert e.doit() == f.doit() + + +def test_issue_4665(): + # Allow only upper or lower limit evaluation + e = Integral(x**2, (x, None, 1)) + f = Integral(x**2, (x, 1, None)) + assert e.doit() == Rational(1, 3) + assert f.doit() == Rational(-1, 3) + assert Integral(x*y, (x, None, y)).subs(y, t) == Integral(x*t, (x, None, t)) + assert Integral(x*y, (x, y, None)).subs(y, t) == Integral(x*t, (x, t, None)) + assert integrate(x**2, (x, None, 1)) == Rational(1, 3) + assert integrate(x**2, (x, 1, None)) == Rational(-1, 3) + assert integrate("x**2", ("x", "1", None)) == Rational(-1, 3) + + +def test_integral_reconstruct(): + e = Integral(x**2, (x, -1, 1)) + assert e == Integral(*e.args) + + +def test_doit_integrals(): + e = Integral(Integral(2*x), (x, 0, 1)) + assert e.doit() == Rational(1, 3) + assert e.doit(deep=False) == Rational(1, 3) + f = Function('f') + # doesn't matter if the integral can't be performed + assert Integral(f(x), (x, 1, 1)).doit() == 0 + # doesn't matter if the limits can't be evaluated + assert Integral(0, (x, 1, Integral(f(x), x))).doit() == 0 + assert Integral(x, (a, 0)).doit() == 0 + limits = ((a, 1, exp(x)), (x, 0)) + assert Integral(a, *limits).doit() == Rational(1, 4) + assert Integral(a, *list(reversed(limits))).doit() == 0 + + +def test_issue_4884(): + assert integrate(sqrt(x)*(1 + x)) == \ + Piecewise( + (2*sqrt(x)*(x + 1)**2/5 - 2*sqrt(x)*(x + 1)/15 - 4*sqrt(x)/15, + Abs(x + 1) > 1), + (2*I*sqrt(-x)*(x + 1)**2/5 - 2*I*sqrt(-x)*(x + 1)/15 - + 4*I*sqrt(-x)/15, True)) + assert integrate(x**x*(1 + log(x))) == x**x + +def test_issue_18153(): + assert integrate(x**n*log(x),x) == \ + Piecewise( + (n*x*x**n*log(x)/(n**2 + 2*n + 1) + + x*x**n*log(x)/(n**2 + 2*n + 1) - x*x**n/(n**2 + 2*n + 1) + , Ne(n, -1)), (log(x)**2/2, True) + ) + + +def test_is_number(): + from sympy.abc import x, y, z + assert Integral(x).is_number is False + assert Integral(1, x).is_number is False + assert Integral(1, (x, 1)).is_number is True + assert Integral(1, (x, 1, 2)).is_number is True + assert Integral(1, (x, 1, y)).is_number is False + assert Integral(1, (x, y)).is_number is False + assert Integral(x, y).is_number is False + assert Integral(x, (y, 1, x)).is_number is False + assert Integral(x, (y, 1, 2)).is_number is False + assert Integral(x, (x, 1, 2)).is_number is True + # `foo.is_number` should always be equivalent to `not foo.free_symbols` + # in each of these cases, there are pseudo-free symbols + i = Integral(x, (y, 1, 1)) + assert i.is_number is False and i.n() == 0 + i = Integral(x, (y, z, z)) + assert i.is_number is False and i.n() == 0 + i = Integral(1, (y, z, z + 2)) + assert i.is_number is False and i.n() == 2.0 + + assert Integral(x*y, (x, 1, 2), (y, 1, 3)).is_number is True + assert Integral(x*y, (x, 1, 2), (y, 1, z)).is_number is False + assert Integral(x, (x, 1)).is_number is True + assert Integral(x, (x, 1, Integral(y, (y, 1, 2)))).is_number is True + assert Integral(Sum(z, (z, 1, 2)), (x, 1, 2)).is_number is True + # it is possible to get a false negative if the integrand is + # actually an unsimplified zero, but this is true of is_number in general. + assert Integral(sin(x)**2 + cos(x)**2 - 1, x).is_number is False + assert Integral(f(x), (x, 0, 1)).is_number is True + + +def test_free_symbols(): + from sympy.abc import x, y, z + assert Integral(0, x).free_symbols == {x} + assert Integral(x).free_symbols == {x} + assert Integral(x, (x, None, y)).free_symbols == {y} + assert Integral(x, (x, y, None)).free_symbols == {y} + assert Integral(x, (x, 1, y)).free_symbols == {y} + assert Integral(x, (x, y, 1)).free_symbols == {y} + assert Integral(x, (x, x, y)).free_symbols == {x, y} + assert Integral(x, x, y).free_symbols == {x, y} + assert Integral(x, (x, 1, 2)).free_symbols == set() + assert Integral(x, (y, 1, 2)).free_symbols == {x} + # pseudo-free in this case + assert Integral(x, (y, z, z)).free_symbols == {x, z} + assert Integral(x, (y, 1, 2), (y, None, None) + ).free_symbols == {x, y} + assert Integral(x, (y, 1, 2), (x, 1, y) + ).free_symbols == {y} + assert Integral(2, (y, 1, 2), (y, 1, x), (x, 1, 2) + ).free_symbols == set() + assert Integral(2, (y, x, 2), (y, 1, x), (x, 1, 2) + ).free_symbols == set() + assert Integral(2, (x, 1, 2), (y, x, 2), (y, 1, 2) + ).free_symbols == {x} + assert Integral(f(x), (f(x), 1, y)).free_symbols == {y} + assert Integral(f(x), (f(x), 1, x)).free_symbols == {x} + + +def test_is_zero(): + from sympy.abc import x, m + assert Integral(0, (x, 1, x)).is_zero + assert Integral(1, (x, 1, 1)).is_zero + assert Integral(1, (x, 1, 2), (y, 2)).is_zero is False + assert Integral(x, (m, 0)).is_zero + assert Integral(x + m, (m, 0)).is_zero is None + i = Integral(m, (m, 1, exp(x)), (x, 0)) + assert i.is_zero is None + assert Integral(m, (x, 0), (m, 1, exp(x))).is_zero is True + + assert Integral(x, (x, oo, oo)).is_zero # issue 8171 + assert Integral(x, (x, -oo, -oo)).is_zero + + # this is zero but is beyond the scope of what is_zero + # should be doing + assert Integral(sin(x), (x, 0, 2*pi)).is_zero is None + + +def test_series(): + from sympy.abc import x + i = Integral(cos(x), (x, x)) + e = i.lseries(x) + assert i.nseries(x, n=8).removeO() == Add(*[next(e) for j in range(4)]) + + +def test_trig_nonelementary_integrals(): + x = Symbol('x') + assert integrate((1 + sin(x))/x, x) == log(x) + Si(x) + # next one comes out as log(x) + log(x**2)/2 + Ci(x) + # so not hardcoding this log ugliness + assert integrate((cos(x) + 2)/x, x).has(Ci) + + +def test_issue_4403(): + x = Symbol('x') + y = Symbol('y') + z = Symbol('z', positive=True) + assert integrate(sqrt(x**2 + z**2), x) == \ + z**2*asinh(x/z)/2 + x*sqrt(x**2 + z**2)/2 + assert integrate(sqrt(x**2 - z**2), x) == \ + x*sqrt(x**2 - z**2)/2 - z**2*log(x + sqrt(x**2 - z**2))/2 + + x = Symbol('x', real=True) + y = Symbol('y', positive=True) + assert integrate(1/(x**2 + y**2)**S('3/2'), x) == \ + x/(y**2*sqrt(x**2 + y**2)) + # If y is real and nonzero, we get x*Abs(y)/(y**3*sqrt(x**2 + y**2)), + # which results from sqrt(1 + x**2/y**2) = sqrt(x**2 + y**2)/|y|. + + +def test_issue_4403_2(): + assert integrate(sqrt(-x**2 - 4), x) == \ + -2*atan(x/sqrt(-4 - x**2)) + x*sqrt(-4 - x**2)/2 + + +def test_issue_4100(): + R = Symbol('R', positive=True) + assert integrate(sqrt(R**2 - x**2), (x, 0, R)) == pi*R**2/4 + + +def test_issue_5167(): + from sympy.abc import w, x, y, z + f = Function('f') + assert Integral(Integral(f(x), x), x) == Integral(f(x), x, x) + assert Integral(f(x)).args == (f(x), Tuple(x)) + assert Integral(Integral(f(x))).args == (f(x), Tuple(x), Tuple(x)) + assert Integral(Integral(f(x)), y).args == (f(x), Tuple(x), Tuple(y)) + assert Integral(Integral(f(x), z), y).args == (f(x), Tuple(z), Tuple(y)) + assert Integral(Integral(Integral(f(x), x), y), z).args == \ + (f(x), Tuple(x), Tuple(y), Tuple(z)) + assert integrate(Integral(f(x), x), x) == Integral(f(x), x, x) + assert integrate(Integral(f(x), y), x) == y*Integral(f(x), x) + assert integrate(Integral(f(x), x), y) in [Integral(y*f(x), x), y*Integral(f(x), x)] + assert integrate(Integral(2, x), x) == x**2 + assert integrate(Integral(2, x), y) == 2*x*y + # don't re-order given limits + assert Integral(1, x, y).args != Integral(1, y, x).args + # do as many as possible + assert Integral(f(x), y, x, y, x).doit() == y**2*Integral(f(x), x, x)/2 + assert Integral(f(x), (x, 1, 2), (w, 1, x), (z, 1, y)).doit() == \ + y*(x - 1)*Integral(f(x), (x, 1, 2)) - (x - 1)*Integral(f(x), (x, 1, 2)) + + +def test_issue_4890(): + z = Symbol('z', positive=True) + assert integrate(exp(-log(x)**2), x) == \ + sqrt(pi)*exp(Rational(1, 4))*erf(log(x) - S.Half)/2 + assert integrate(exp(log(x)**2), x) == \ + sqrt(pi)*exp(Rational(-1, 4))*erfi(log(x)+S.Half)/2 + assert integrate(exp(-z*log(x)**2), x) == \ + sqrt(pi)*exp(1/(4*z))*erf(sqrt(z)*log(x) - 1/(2*sqrt(z)))/(2*sqrt(z)) + + +def test_issue_4551(): + assert not integrate(1/(x*sqrt(1 - x**2)), x).has(Integral) + + +def test_issue_4376(): + n = Symbol('n', integer=True, positive=True) + assert simplify(integrate(n*(x**(1/n) - 1), (x, 0, S.Half)) - + (n**2 - 2**(1/n)*n**2 - n*2**(1/n))/(2**(1 + 1/n) + n*2**(1 + 1/n))) == 0 + + +def test_issue_4517(): + assert integrate((sqrt(x) - x**3)/x**Rational(1, 3), x) == \ + 6*x**Rational(7, 6)/7 - 3*x**Rational(11, 3)/11 + + +def test_issue_4527(): + k, m = symbols('k m', integer=True) + assert integrate(sin(k*x)*sin(m*x), (x, 0, pi)).simplify() == \ + Piecewise((0, Eq(k, 0) | Eq(m, 0)), + (-pi/2, Eq(k, -m) | (Eq(k, 0) & Eq(m, 0))), + (pi/2, Eq(k, m) | (Eq(k, 0) & Eq(m, 0))), + (0, True)) + # Should be possible to further simplify to: + # Piecewise( + # (0, Eq(k, 0) | Eq(m, 0)), + # (-pi/2, Eq(k, -m)), + # (pi/2, Eq(k, m)), + # (0, True)) + assert integrate(sin(k*x)*sin(m*x), (x,)) == Piecewise( + (0, And(Eq(k, 0), Eq(m, 0))), + (-x*sin(m*x)**2/2 - x*cos(m*x)**2/2 + sin(m*x)*cos(m*x)/(2*m), Eq(k, -m)), + (x*sin(m*x)**2/2 + x*cos(m*x)**2/2 - sin(m*x)*cos(m*x)/(2*m), Eq(k, m)), + (m*sin(k*x)*cos(m*x)/(k**2 - m**2) - + k*sin(m*x)*cos(k*x)/(k**2 - m**2), True)) + + +def test_issue_4199(): + ypos = Symbol('y', positive=True) + # TODO: Remove conds='none' below, let the assumption take care of it. + assert integrate(exp(-I*2*pi*ypos*x)*x, (x, -oo, oo), conds='none') == \ + Integral(exp(-I*2*pi*ypos*x)*x, (x, -oo, oo)) + + +def test_issue_3940(): + a, b, c, d = symbols('a:d', positive=True) + assert integrate(exp(-x**2 + I*c*x), x) == \ + -sqrt(pi)*exp(-c**2/4)*erf(I*c/2 - x)/2 + assert integrate(exp(a*x**2 + b*x + c), x).equals( + sqrt(pi)*exp(c - b**2/(4*a))*erfi((2*a*x + b)/(2*sqrt(a)))/(2*sqrt(a))) + + from sympy.core.function import expand_mul + from sympy.abc import k + assert expand_mul(integrate(exp(-x**2)*exp(I*k*x), (x, -oo, oo))) == \ + sqrt(pi)*exp(-k**2/4) + a, d = symbols('a d', positive=True) + assert expand_mul(integrate(exp(-a*x**2 + 2*d*x), (x, -oo, oo))) == \ + sqrt(pi)*exp(d**2/a)/sqrt(a) + + +def test_issue_5413(): + # Note that this is not the same as testing ratint() because integrate() + # pulls out the coefficient. + assert integrate(-a/(a**2 + x**2), x) == I*log(-I*a + x)/2 - I*log(I*a + x)/2 + + +def test_issue_4892a(): + A, z = symbols('A z') + c = Symbol('c', nonzero=True) + P1 = -A*exp(-z) + P2 = -A/(c*t)*(sin(x)**2 + cos(y)**2) + + h1 = -sin(x)**2 - cos(y)**2 + h2 = -sin(x)**2 + sin(y)**2 - 1 + + # there is still some non-deterministic behavior in integrate + # or trigsimp which permits one of the following + assert integrate(c*(P2 - P1), t) in [ + c*(-A*(-h1)*log(c*t)/c + A*t*exp(-z)), + c*(-A*(-h2)*log(c*t)/c + A*t*exp(-z)), + c*( A* h1 *log(c*t)/c + A*t*exp(-z)), + c*( A* h2 *log(c*t)/c + A*t*exp(-z)), + (A*c*t - A*(-h1)*log(t)*exp(z))*exp(-z), + (A*c*t - A*(-h2)*log(t)*exp(z))*exp(-z), + ] + + +def test_issue_4892b(): + # Issues relating to issue 4596 are making the actual result of this hard + # to test. The answer should be something like + # + # (-sin(y) + sqrt(-72 + 48*cos(y) - 8*cos(y)**2)/2)*log(x + sqrt(-72 + + # 48*cos(y) - 8*cos(y)**2)/(2*(3 - cos(y)))) + (-sin(y) - sqrt(-72 + + # 48*cos(y) - 8*cos(y)**2)/2)*log(x - sqrt(-72 + 48*cos(y) - + # 8*cos(y)**2)/(2*(3 - cos(y)))) + x**2*sin(y)/2 + 2*x*cos(y) + + expr = (sin(y)*x**3 + 2*cos(y)*x**2 + 12)/(x**2 + 2) + assert trigsimp(factor(integrate(expr, x).diff(x) - expr)) == 0 + + +def test_issue_5178(): + assert integrate(sin(x)*f(y, z), (x, 0, pi), (y, 0, pi), (z, 0, pi)) == \ + 2*Integral(f(y, z), (y, 0, pi), (z, 0, pi)) + + +def test_integrate_series(): + f = sin(x).series(x, 0, 10) + g = x**2/2 - x**4/24 + x**6/720 - x**8/40320 + x**10/3628800 + O(x**11) + + assert integrate(f, x) == g + assert diff(integrate(f, x), x) == f + + assert integrate(O(x**5), x) == O(x**6) + + +def test_atom_bug(): + from sympy.integrals.heurisch import heurisch + assert heurisch(meijerg([], [], [1], [], x), x) is None + + +def test_limit_bug(): + z = Symbol('z', zero=False) + assert integrate(sin(x*y*z), (x, 0, pi), (y, 0, pi)).together() == \ + (log(z) - Ci(pi**2*z) + EulerGamma + 2*log(pi))/z + + +def test_issue_4703(): + g = Function('g') + assert integrate(exp(x)*g(x), x).has(Integral) + + +def test_issue_1888(): + f = Function('f') + assert integrate(f(x).diff(x)**2, x).has(Integral) + +# The following tests work using meijerint. + + +def test_issue_3558(): + assert integrate(cos(x*y), (x, -pi/2, pi/2), (y, 0, pi)) == 2*Si(pi**2/2) + + +def test_issue_4422(): + assert integrate(1/sqrt(16 + 4*x**2), x) == asinh(x/2) / 2 + + +def test_issue_4493(): + assert simplify(integrate(x*sqrt(1 + 2*x), x)) == \ + sqrt(2*x + 1)*(6*x**2 + x - 1)/15 + + +def test_issue_4737(): + assert integrate(sin(x)/x, (x, -oo, oo)) == pi + assert integrate(sin(x)/x, (x, 0, oo)) == pi/2 + assert integrate(sin(x)/x, x) == Si(x) + + +def test_issue_4992(): + # Note: psi in _check_antecedents becomes NaN. + from sympy.core.function import expand_func + a = Symbol('a', positive=True) + assert simplify(expand_func(integrate(exp(-x)*log(x)*x**a, (x, 0, oo)))) == \ + (a*polygamma(0, a) + 1)*gamma(a) + + +def test_issue_4487(): + from sympy.functions.special.gamma_functions import lowergamma + assert simplify(integrate(exp(-x)*x**y, x)) == lowergamma(y + 1, x) + + +def test_issue_4215(): + x = Symbol("x") + assert integrate(1/(x**2), (x, -1, 1)) is oo + + +def test_issue_4400(): + n = Symbol('n', integer=True, positive=True) + assert integrate((x**n)*log(x), x) == \ + n*x*x**n*log(x)/(n**2 + 2*n + 1) + x*x**n*log(x)/(n**2 + 2*n + 1) - \ + x*x**n/(n**2 + 2*n + 1) + + +def test_issue_6253(): + # Note: this used to raise NotImplementedError + # Note: psi in _check_antecedents becomes NaN. + assert integrate((sqrt(1 - x) + sqrt(1 + x))**2/x, x, meijerg=True) == \ + Integral((sqrt(-x + 1) + sqrt(x + 1))**2/x, x) + + +def test_issue_4153(): + assert integrate(1/(1 + x + y + z), (x, 0, 1), (y, 0, 1), (z, 0, 1)) in [ + -12*log(3) - 3*log(6)/2 + 3*log(8)/2 + 5*log(2) + 7*log(4), + 6*log(2) + 8*log(4) - 27*log(3)/2, 22*log(2) - 27*log(3)/2, + -12*log(3) - 3*log(6)/2 + 47*log(2)/2] + + +def test_issue_4326(): + R, b, h = symbols('R b h') + # It doesn't matter if we can do the integral. Just make sure the result + # doesn't contain nan. This is really a test against _eval_interval. + e = integrate(((h*(x - R + b))/b)*sqrt(R**2 - x**2), (x, R - b, R)) + assert not e.has(nan) + # See that it evaluates + assert not e.has(Integral) + + +def test_powers(): + assert integrate(2**x + 3**x, x) == 2**x/log(2) + 3**x/log(3) + + +def test_manual_option(): + raises(ValueError, lambda: integrate(1/x, x, manual=True, meijerg=True)) + # an example of a function that manual integration cannot handle + assert integrate(log(1+x)/x, (x, 0, 1), manual=True).has(Integral) + + +def test_meijerg_option(): + raises(ValueError, lambda: integrate(1/x, x, meijerg=True, risch=True)) + # an example of a function that meijerg integration cannot handle + assert integrate(tan(x), x, meijerg=True) == Integral(tan(x), x) + + +def test_risch_option(): + # risch=True only allowed on indefinite integrals + raises(ValueError, lambda: integrate(1/log(x), (x, 0, oo), risch=True)) + assert integrate(exp(-x**2), x, risch=True) == NonElementaryIntegral(exp(-x**2), x) + assert integrate(log(1/x)*y, x, y, risch=True) == y**2*(x*log(1/x)/2 + x/2) + assert integrate(erf(x), x, risch=True) == Integral(erf(x), x) + # TODO: How to test risch=False? + + +@slow +def test_heurisch_option(): + raises(ValueError, lambda: integrate(1/x, x, risch=True, heurisch=True)) + # an integral that heurisch can handle + assert integrate(exp(x**2), x, heurisch=True) == sqrt(pi)*erfi(x)/2 + # an integral that heurisch currently cannot handle + assert integrate(exp(x)/x, x, heurisch=True) == Integral(exp(x)/x, x) + # an integral where heurisch currently hangs, issue 15471 + assert integrate(log(x)*cos(log(x))/x**Rational(3, 4), x, heurisch=False) == ( + -128*x**Rational(1, 4)*sin(log(x))/289 + 240*x**Rational(1, 4)*cos(log(x))/289 + + (16*x**Rational(1, 4)*sin(log(x))/17 + 4*x**Rational(1, 4)*cos(log(x))/17)*log(x)) + + +def test_issue_6828(): + f = 1/(1.08*x**2 - 4.3) + g = integrate(f, x).diff(x) + assert verify_numerically(f, g, tol=1e-12) + + +def test_issue_4803(): + x_max = Symbol("x_max") + assert integrate(y/pi*exp(-(x_max - x)/cos(a)), x) == \ + y*exp((x - x_max)/cos(a))*cos(a)/pi + + +def test_issue_4234(): + assert integrate(1/sqrt(1 + tan(x)**2)) == tan(x)/sqrt(1 + tan(x)**2) + + +def test_issue_4492(): + assert simplify(integrate(x**2 * sqrt(5 - x**2), x)).factor( + deep=True) == Piecewise( + (I*(2*x**5 - 15*x**3 + 25*x - 25*sqrt(x**2 - 5)*acosh(sqrt(5)*x/5)) / + (8*sqrt(x**2 - 5)), (x > sqrt(5)) | (x < -sqrt(5))), + ((2*x**5 - 15*x**3 + 25*x - 25*sqrt(5 - x**2)*asin(sqrt(5)*x/5)) / + (-8*sqrt(-x**2 + 5)), True)) + + +def test_issue_2708(): + # This test needs to use an integration function that can + # not be evaluated in closed form. Update as needed. + f = 1/(a + z + log(z)) + integral_f = NonElementaryIntegral(f, (z, 2, 3)) + assert Integral(f, (z, 2, 3)).doit() == integral_f + assert integrate(f + exp(z), (z, 2, 3)) == integral_f - exp(2) + exp(3) + assert integrate(2*f + exp(z), (z, 2, 3)) == \ + 2*integral_f - exp(2) + exp(3) + assert integrate(exp(1.2*n*s*z*(-t + z)/t), (z, 0, x)) == \ + NonElementaryIntegral(exp(-1.2*n*s*z)*exp(1.2*n*s*z**2/t), + (z, 0, x)) + + +def test_issue_2884(): + f = (4.000002016020*x + 4.000002016020*y + 4.000006024032)*exp(10.0*x) + e = integrate(f, (x, 0.1, 0.2)) + assert str(e) == '1.86831064982608*y + 2.16387491480008' + + +def test_issue_8368i(): + from sympy.functions.elementary.complexes import arg, Abs + assert integrate(exp(-s*x)*cosh(x), (x, 0, oo)) == \ + Piecewise( + ( pi*Piecewise( + ( -s/(pi*(-s**2 + 1)), + Abs(s**2) < 1), + ( 1/(pi*s*(1 - 1/s**2)), + Abs(s**(-2)) < 1), + ( meijerg( + ((S.Half,), (0, 0)), + ((0, S.Half), (0,)), + polar_lift(s)**2), + True) + ), + s**2 > 1 + ), + ( + Integral(exp(-s*x)*cosh(x), (x, 0, oo)), + True)) + assert integrate(exp(-s*x)*sinh(x), (x, 0, oo)) == \ + Piecewise( + ( -1/(s + 1)/2 - 1/(-s + 1)/2, + And( + Abs(s) > 1, + Abs(arg(s)) < pi/2, + Abs(arg(s)) <= pi/2 + )), + ( Integral(exp(-s*x)*sinh(x), (x, 0, oo)), + True)) + + +def test_issue_8901(): + assert integrate(sinh(1.0*x)) == 1.0*cosh(1.0*x) + assert integrate(tanh(1.0*x)) == 1.0*x - 1.0*log(tanh(1.0*x) + 1) + assert integrate(tanh(x)) == x - log(tanh(x) + 1) + + +@slow +def test_issue_8945(): + assert integrate(sin(x)**3/x, (x, 0, 1)) == -Si(3)/4 + 3*Si(1)/4 + assert integrate(sin(x)**3/x, (x, 0, oo)) == pi/4 + assert integrate(cos(x)**2/x**2, x) == -Si(2*x) - cos(2*x)/(2*x) - 1/(2*x) + + +@slow +def test_issue_7130(): + i, L, a, b = symbols('i L a b') + integrand = (cos(pi*i*x/L)**2 / (a + b*x)).rewrite(exp) + assert x not in integrate(integrand, (x, 0, L)).free_symbols + + +def test_issue_10567(): + a, b, c, t = symbols('a b c t') + vt = Matrix([a*t, b, c]) + assert integrate(vt, t) == Integral(vt, t).doit() + assert integrate(vt, t) == Matrix([[a*t**2/2], [b*t], [c*t]]) + + +def test_issue_11742(): + assert integrate(sqrt(-x**2 + 8*x + 48), (x, 4, 12)) == 16*pi + + +def test_issue_11856(): + t = symbols('t') + assert integrate(sinc(pi*t), t) == Si(pi*t)/pi + + +@slow +def test_issue_11876(): + assert integrate(sqrt(log(1/x)), (x, 0, 1)) == sqrt(pi)/2 + + +def test_issue_4950(): + assert integrate((-60*exp(x) - 19.2*exp(4*x))*exp(4*x), x) ==\ + -2.4*exp(8*x) - 12.0*exp(5*x) + + +def test_issue_4968(): + assert integrate(sin(log(x**2))) == x*sin(log(x**2))/5 - 2*x*cos(log(x**2))/5 + + +def test_singularities(): + assert integrate(1/x**2, (x, -oo, oo)) is oo + assert integrate(1/x**2, (x, -1, 1)) is oo + assert integrate(1/(x - 1)**2, (x, -2, 2)) is oo + + assert integrate(1/x**2, (x, 1, -1)) is -oo + assert integrate(1/(x - 1)**2, (x, 2, -2)) is -oo + + +def test_issue_12645(): + x, y = symbols('x y', real=True) + assert (integrate(sin(x*x*x + y*y), + (x, -sqrt(pi - y*y), sqrt(pi - y*y)), + (y, -sqrt(pi), sqrt(pi))) + == Integral(sin(x**3 + y**2), + (x, -sqrt(-y**2 + pi), sqrt(-y**2 + pi)), + (y, -sqrt(pi), sqrt(pi)))) + + +def test_issue_12677(): + assert integrate(sin(x) / (cos(x)**3), (x, 0, pi/6)) == Rational(1, 6) + + +def test_issue_14078(): + assert integrate((cos(3*x)-cos(x))/x, (x, 0, oo)) == -log(3) + + +def test_issue_14064(): + assert integrate(1/cosh(x), (x, 0, oo)) == pi/2 + + +def test_issue_14027(): + assert integrate(1/(1 + exp(x - S.Half)/(1 + exp(x))), x) == \ + x - exp(S.Half)*log(exp(x) + exp(S.Half)/(1 + exp(S.Half)))/(exp(S.Half) + E) + + +def test_issue_8170(): + assert integrate(tan(x), (x, 0, pi/2)) is S.Infinity + + +def test_issue_8440_14040(): + assert integrate(1/x, (x, -1, 1)) is S.NaN + assert integrate(1/(x + 1), (x, -2, 3)) is S.NaN + + +def test_issue_14096(): + assert integrate(1/(x + y)**2, (x, 0, 1)) == -1/(y + 1) + 1/y + assert integrate(1/(1 + x + y + z)**2, (x, 0, 1), (y, 0, 1), (z, 0, 1)) == \ + -4*log(4) - 6*log(2) + 9*log(3) + + +def test_issue_14144(): + assert Abs(integrate(1/sqrt(1 - x**3), (x, 0, 1)).n() - 1.402182) < 1e-6 + assert Abs(integrate(sqrt(1 - x**3), (x, 0, 1)).n() - 0.841309) < 1e-6 + + +def test_issue_14375(): + # This raised a TypeError. The antiderivative has exp_polar, which + # may be possible to unpolarify, so the exact output is not asserted here. + assert integrate(exp(I*x)*log(x), x).has(Ei) + + +def test_issue_14437(): + f = Function('f')(x, y, z) + assert integrate(f, (x, 0, 1), (y, 0, 2), (z, 0, 3)) == \ + Integral(f, (x, 0, 1), (y, 0, 2), (z, 0, 3)) + + +def test_issue_14470(): + assert integrate(1/sqrt(exp(x) + 1), x) == log(sqrt(exp(x) + 1) - 1) - log(sqrt(exp(x) + 1) + 1) + + +def test_issue_14877(): + f = exp(1 - exp(x**2)*x + 2*x**2)*(2*x**3 + x)/(1 - exp(x**2)*x)**2 + assert integrate(f, x) == \ + -exp(2*x**2 - x*exp(x**2) + 1)/(x*exp(3*x**2) - exp(2*x**2)) + + +def test_issue_14782(): + f = sqrt(-x**2 + 1)*(-x**2 + x) + assert integrate(f, [x, -1, 1]) == - pi / 8 + + +@slow +def test_issue_14782_slow(): + f = sqrt(-x**2 + 1)*(-x**2 + x) + assert integrate(f, [x, 0, 1]) == S.One / 3 - pi / 16 + + +def test_issue_12081(): + f = x**(Rational(-3, 2))*exp(-x) + assert integrate(f, [x, 0, oo]) is oo + + +def test_issue_15285(): + y = 1/x - 1 + f = 4*y*exp(-2*y)/x**2 + assert integrate(f, [x, 0, 1]) == 1 + + +def test_issue_15432(): + assert integrate(x**n * exp(-x) * log(x), (x, 0, oo)).gammasimp() == Piecewise( + (gamma(n + 1)*polygamma(0, n) + gamma(n + 1)/n, re(n) + 1 > 0), + (Integral(x**n*exp(-x)*log(x), (x, 0, oo)), True)) + + +def test_issue_15124(): + omega = IndexedBase('omega') + m, p = symbols('m p', cls=Idx) + assert integrate(exp(x*I*(omega[m] + omega[p])), x, conds='none') == \ + -I*exp(I*x*omega[m])*exp(I*x*omega[p])/(omega[m] + omega[p]) + + +def test_issue_15218(): + with warns_deprecated_sympy(): + Integral(Eq(x, y)) + with warns_deprecated_sympy(): + assert Integral(Eq(x, y), x) == Eq(Integral(x, x), Integral(y, x)) + with warns_deprecated_sympy(): + assert Integral(Eq(x, y), x).doit() == Eq(x**2/2, x*y) + with warns(SymPyDeprecationWarning, test_stacklevel=False): + # The warning is made in the ExprWithLimits superclass. The stacklevel + # is correct for integrate(Eq) but not Eq.integrate + assert Eq(x, y).integrate(x) == Eq(x**2/2, x*y) + + # These are not deprecated because they are definite integrals + assert integrate(Eq(x, y), (x, 0, 1)) == Eq(S.Half, y) + assert Eq(x, y).integrate((x, 0, 1)) == Eq(S.Half, y) + + +def test_issue_15292(): + res = integrate(exp(-x**2*cos(2*t)) * cos(x**2*sin(2*t)), (x, 0, oo)) + assert isinstance(res, Piecewise) + assert gammasimp((res - sqrt(pi)/2 * cos(t)).subs(t, pi/6)) == 0 + + +def test_issue_4514(): + assert integrate(sin(2*x)/sin(x), x) == 2*sin(x) + + +def test_issue_15457(): + x, a, b = symbols('x a b', real=True) + definite = integrate(exp(Abs(x-2)), (x, a, b)) + indefinite = integrate(exp(Abs(x-2)), x) + assert definite.subs({a: 1, b: 3}) == -2 + 2*E + assert indefinite.subs(x, 3) - indefinite.subs(x, 1) == -2 + 2*E + assert definite.subs({a: -3, b: -1}) == -exp(3) + exp(5) + assert indefinite.subs(x, -1) - indefinite.subs(x, -3) == -exp(3) + exp(5) + + +def test_issue_15431(): + assert integrate(x*exp(x)*log(x), x) == \ + (x*exp(x) - exp(x))*log(x) - exp(x) + Ei(x) + + +def test_issue_15640_log_substitutions(): + f = x/log(x) + F = Ei(2*log(x)) + assert integrate(f, x) == F and F.diff(x) == f + f = x**3/log(x)**2 + F = -x**4/log(x) + 4*Ei(4*log(x)) + assert integrate(f, x) == F and F.diff(x) == f + f = sqrt(log(x))/x**2 + F = -sqrt(pi)*erfc(sqrt(log(x)))/2 - sqrt(log(x))/x + assert integrate(f, x) == F and F.diff(x) == f + + +def test_issue_15509(): + from sympy.vector import CoordSys3D + N = CoordSys3D('N') + x = N.x + assert integrate(cos(a*x + b), (x, x_1, x_2), heurisch=True) == Piecewise( + (-sin(a*x_1 + b)/a + sin(a*x_2 + b)/a, (a > -oo) & (a < oo) & Ne(a, 0)), \ + (-x_1*cos(b) + x_2*cos(b), True)) + + +def test_issue_4311_fast(): + x = symbols('x', real=True) + assert integrate(x*abs(9-x**2), x) == Piecewise( + (x**4/4 - 9*x**2/2, x <= -3), + (-x**4/4 + 9*x**2/2 - Rational(81, 2), x <= 3), + (x**4/4 - 9*x**2/2, True)) + + +def test_integrate_with_complex_constants(): + K = Symbol('K', positive=True) + x = Symbol('x', real=True) + m = Symbol('m', real=True) + t = Symbol('t', real=True) + assert integrate(exp(-I*K*x**2+m*x), x) == sqrt(pi)*exp(-I*m**2 + /(4*K))*erfi((-2*I*K*x + m)/(2*sqrt(K)*sqrt(-I)))/(2*sqrt(K)*sqrt(-I)) + assert integrate(1/(1 + I*x**2), x) == (-I*(sqrt(-I)*log(x - I*sqrt(-I))/2 + - sqrt(-I)*log(x + I*sqrt(-I))/2)) + assert integrate(exp(-I*x**2), x) == sqrt(pi)*erf(sqrt(I)*x)/(2*sqrt(I)) + + assert integrate((1/(exp(I*t)-2)), t) == -t/2 - I*log(exp(I*t) - 2)/2 + assert integrate((1/(exp(I*t)-2)), (t, 0, 2*pi)) == -pi + + +def test_issue_14241(): + x = Symbol('x') + n = Symbol('n', positive=True, integer=True) + assert integrate(n * x ** (n - 1) / (x + 1), x) == \ + n**2*x**n*lerchphi(x*exp_polar(I*pi), 1, n)*gamma(n)/gamma(n + 1) + + +def test_issue_13112(): + assert integrate(sin(t)**2 / (5 - 4*cos(t)), [t, 0, 2*pi]) == pi / 4 + + +def test_issue_14709b(): + h = Symbol('h', positive=True) + i = integrate(x*acos(1 - 2*x/h), (x, 0, h)) + assert i == 5*h**2*pi/16 + + +def test_issue_8614(): + x = Symbol('x') + t = Symbol('t') + assert integrate(exp(t)/t, (t, -oo, x)) == Ei(x) + assert integrate((exp(-x) - exp(-2*x))/x, (x, 0, oo)) == log(2) + + +@slow +def test_issue_15494(): + s = symbols('s', positive=True) + + integrand = (exp(s/2) - 2*exp(1.6*s) + exp(s))*exp(s) + solution = integrate(integrand, s) + assert solution != S.NaN + # Not sure how to test this properly as it is a symbolic expression with floats + # assert str(solution) == '0.666666666666667*exp(1.5*s) + 0.5*exp(2.0*s) - 0.769230769230769*exp(2.6*s)' + # Maybe + assert abs(solution.subs(s, 1) - (-3.67440080236188)) <= 1e-8 + + integrand = (exp(s/2) - 2*exp(S(8)/5*s) + exp(s))*exp(s) + assert integrate(integrand, s) == -10*exp(13*s/5)/13 + 2*exp(3*s/2)/3 + exp(2*s)/2 + + +def test_li_integral(): + y = Symbol('y') + assert Integral(li(y*x**2), x).doit() == Piecewise((x*li(x**2*y) - \ + x*Ei(3*log(x**2*y)/2)/sqrt(x**2*y), + Ne(y, 0)), (0, True)) + + +def test_issue_17473(): + x = Symbol('x') + n = Symbol('n') + h = S.Half + ans = x**(n + 1)*gamma(h + h/n)*hyper((h + h/n,), + (3*h, 3*h + h/n), -x**(2*n)/4)/(2*n*gamma(3*h + h/n)) + got = integrate(sin(x**n), x) + assert got == ans + _x = Symbol('x', zero=False) + reps = {x: _x} + assert integrate(sin(_x**n), _x) == ans.xreplace(reps).expand() + + +def test_issue_17671(): + assert integrate(log(log(x)) / x**2, [x, 1, oo]) == -EulerGamma + assert integrate(log(log(x)) / x**3, [x, 1, oo]) == -log(2)/2 - EulerGamma/2 + assert integrate(log(log(x)) / x**10, [x, 1, oo]) == -log(9)/9 - EulerGamma/9 + + +def test_issue_2975(): + w = Symbol('w') + C = Symbol('C') + y = Symbol('y') + assert integrate(1/(y**2+C)**(S(3)/2), (y, -w/2, w/2)) == w/(C**(S(3)/2)*sqrt(1 + w**2/(4*C))) + + +def test_issue_7827(): + x, n, M = symbols('x n M') + N = Symbol('N', integer=True) + assert integrate(summation(x*n, (n, 1, N)), x) == x**2*(N**2/4 + N/4) + assert integrate(summation(x*sin(n), (n,1,N)), x) == \ + Sum(x**2*sin(n)/2, (n, 1, N)) + assert integrate(summation(sin(n*x), (n,1,N)), x) == \ + Sum(Piecewise((-cos(n*x)/n, Ne(n, 0)), (0, True)), (n, 1, N)) + assert integrate(integrate(summation(sin(n*x), (n,1,N)), x), x) == \ + Piecewise((Sum(Piecewise((-sin(n*x)/n**2, Ne(n, 0)), (-x/n, True)), + (n, 1, N)), (n > -oo) & (n < oo) & Ne(n, 0)), (0, True)) + assert integrate(Sum(x, (n, 1, M)), x) == M*x**2/2 + raises(ValueError, lambda: integrate(Sum(x, (x, y, n)), y)) + raises(ValueError, lambda: integrate(Sum(x, (x, 1, n)), n)) + raises(ValueError, lambda: integrate(Sum(x, (x, 1, y)), x)) + + +def test_issue_4231(): + f = (1 + 2*x + sqrt(x + log(x))*(1 + 3*x) + x**2)/(x*(x + sqrt(x + log(x)))*sqrt(x + log(x))) + assert integrate(f, x) == 2*sqrt(x + log(x)) + 2*log(x + sqrt(x + log(x))) + + +def test_issue_17841(): + f = diff(1/(x**2+x+I), x) + assert integrate(f, x) == 1/(x**2 + x + I) + + +def test_issue_21034(): + x = Symbol('x', real=True, nonzero=True) + f1 = x*(-x**4/asin(5)**4 - x*sinh(x + log(asin(5))) + 5) + f2 = (x + cosh(cos(4)))/(x*(x + 1/(12*x))) + + assert integrate(f1, x) == \ + -x**6/(6*asin(5)**4) - x**2*cosh(x + log(asin(5))) + 5*x**2/2 + 2*x*sinh(x + log(asin(5))) - 2*cosh(x + log(asin(5))) + + assert integrate(f2, x) == \ + log(x**2 + S(1)/12)/2 + 2*sqrt(3)*cosh(cos(4))*atan(2*sqrt(3)*x) + + +def test_issue_4187(): + assert integrate(log(x)*exp(-x), x) == Ei(-x) - exp(-x)*log(x) + assert integrate(log(x)*exp(-x), (x, 0, oo)) == -EulerGamma + + +def test_issue_5547(): + L = Symbol('L') + z = Symbol('z') + r0 = Symbol('r0') + R0 = Symbol('R0') + + assert integrate(r0**2*cos(z)**2, (z, -L/2, L/2)) == -r0**2*(-L/4 - + sin(L/2)*cos(L/2)/2) + r0**2*(L/4 + sin(L/2)*cos(L/2)/2) + + assert integrate(r0**2*cos(R0*z)**2, (z, -L/2, L/2)) == Piecewise( + (-r0**2*(-L*R0/4 - sin(L*R0/2)*cos(L*R0/2)/2)/R0 + + r0**2*(L*R0/4 + sin(L*R0/2)*cos(L*R0/2)/2)/R0, (R0 > -oo) & (R0 < oo) & Ne(R0, 0)), + (L*r0**2, True)) + + w = 2*pi*z/L + + sol = sqrt(2)*sqrt(L)*r0**2*fresnelc(sqrt(2)*sqrt(L))*gamma(S.One/4)/(16*gamma(S(5)/4)) + L*r0**2/2 + + assert integrate(r0**2*cos(w*z)**2, (z, -L/2, L/2)) == sol + + +def test_issue_15810(): + assert integrate(1/(2**(2*x/3) + 1), (x, 0, oo)) == Rational(3, 2) + + +def test_issue_21024(): + x = Symbol('x', real=True, nonzero=True) + f = log(x)*log(4*x) + log(3*x + exp(2)) + F = x*log(x)**2 + x*log(3*x + exp(2)) + x*(1 - 2*log(2)) + \ + (-2*x + 2*x*log(2))*log(x) + exp(2)*log(3*x + exp(2))/3 + assert F == integrate(f, x) + + f = (x + exp(3))/x**2 + F = log(x) - exp(3)/x + assert F == integrate(f, x) + + f = (x**2 + exp(5))/x + F = x**2/2 + exp(5)*log(x) + assert F == integrate(f, x) + + f = x/(2*x + tanh(1)) + F = x/2 - log(2*x + tanh(1))*tanh(1)/4 + assert F == integrate(f, x) + + f = x - sinh(4)/x + F = x**2/2 - log(x)*sinh(4) + assert F == integrate(f, x) + + f = log(x + exp(5)/x) + F = x*log(x + exp(5)/x) - x + 2*exp(Rational(5, 2))*atan(x*exp(Rational(-5, 2))) + assert F == integrate(f, x) + + f = x**5/(x + E) + F = x**5/5 - E*x**4/4 + x**3*exp(2)/3 - x**2*exp(3)/2 + x*exp(4) - exp(5)*log(x + E) + assert F == integrate(f, x) + + f = 4*x/(x + sinh(5)) + F = 4*x - 4*log(x + sinh(5))*sinh(5) + assert F == integrate(f, x) + + f = x**2/(2*x + sinh(2)) + F = x**2/4 - x*sinh(2)/4 + log(2*x + sinh(2))*sinh(2)**2/8 + assert F == integrate(f, x) + + f = -x**2/(x + E) + F = -x**2/2 + E*x - exp(2)*log(x + E) + assert F == integrate(f, x) + + f = (2*x + 3)*exp(5)/x + F = 2*x*exp(5) + 3*exp(5)*log(x) + assert F == integrate(f, x) + + f = x + 2 + cosh(3)/x + F = x**2/2 + 2*x + log(x)*cosh(3) + assert F == integrate(f, x) + + f = x - tanh(1)/x**3 + F = x**2/2 + tanh(1)/(2*x**2) + assert F == integrate(f, x) + + f = (3*x - exp(6))/x + F = 3*x - exp(6)*log(x) + assert F == integrate(f, x) + + f = x**4/(x + exp(5))**2 + x + F = x**3/3 + x**2*(Rational(1, 2) - exp(5)) + 3*x*exp(10) - 4*exp(15)*log(x + exp(5)) - exp(20)/(x + exp(5)) + assert F == integrate(f, x) + + f = x*(x + exp(10)/x**2) + x + F = x**3/3 + x**2/2 + exp(10)*log(x) + assert F == integrate(f, x) + + f = x + x/(5*x + sinh(3)) + F = x**2/2 + x/5 - log(5*x + sinh(3))*sinh(3)/25 + assert F == integrate(f, x) + + f = (x + exp(3))/(2*x**2 + 2*x) + F = exp(3)*log(x)/2 - exp(3)*log(x + 1)/2 + log(x + 1)/2 + assert F == integrate(f, x).expand() + + f = log(x + 4*sinh(4)) + F = x*log(x + 4*sinh(4)) - x + 4*log(x + 4*sinh(4))*sinh(4) + assert F == integrate(f, x) + + f = -x + 20*(exp(-5) - atan(4)/x)**3*sin(4)/x + F = (-x**2*exp(15)/2 + 20*log(x)*sin(4) - (-180*x**2*exp(5)*sin(4)*atan(4) + 90*x*exp(10)*sin(4)*atan(4)**2 - \ + 20*exp(15)*sin(4)*atan(4)**3)/(3*x**3))*exp(-15) + assert F == integrate(f, x) + + f = 2*x**2*exp(-4) + 6/x + F_true = (2*x**3/3 + 6*exp(4)*log(x))*exp(-4) + assert F_true == integrate(f, x) + + +def test_issue_21721(): + a = Symbol('a') + assert integrate(1/(pi*(1+(x-a)**2)),(x,-oo,oo)).expand() == \ + -Heaviside(im(a) - 1, 0) + Heaviside(im(a) + 1, 0) + + +def test_issue_21831(): + theta = symbols('theta') + assert integrate(cos(3*theta)/(5-4*cos(theta)), (theta, 0, 2*pi)) == pi/12 + integrand = cos(2*theta)/(5 - 4*cos(theta)) + assert integrate(integrand, (theta, 0, 2*pi)) == pi/6 + + +@slow +def test_issue_22033_integral(): + assert integrate((x**2 - Rational(1, 4))**2 * sqrt(1 - x**2), (x, -1, 1)) == pi/32 + + +@slow +def test_issue_21671(): + assert integrate(1,(z,x**2+y**2,2-x**2-y**2),(y,-sqrt(1-x**2),sqrt(1-x**2)),(x,-1,1)) == pi + assert integrate(-4*(1 - x**2)**(S(3)/2)/3 + 2*sqrt(1 - x**2)*(2 - 2*x**2), (x, -1, 1)) == pi + + +def test_issue_18527(): + # The manual integrator can not currently solve this. Assert that it does + # not give an incorrect result involving Abs when x has real assumptions. + xr = symbols('xr', real=True) + expr = (cos(x)/(4+(sin(x))**2)) + res_real = integrate(expr.subs(x, xr), xr, manual=True).subs(xr, x) + assert integrate(expr, x, manual=True) == res_real == Integral(expr, x) + + +def test_issue_23718(): + f = 1/(b*cos(x) + a*sin(x)) + Fpos = (-log(-a/b + tan(x/2) - sqrt(a**2 + b**2)/b)/sqrt(a**2 + b**2) + +log(-a/b + tan(x/2) + sqrt(a**2 + b**2)/b)/sqrt(a**2 + b**2)) + F = Piecewise( + # XXX: The zoo case here is for a=b=0 so it should just be zoo or maybe + # it doesn't really need to be included at all given that the original + # integrand is really undefined in that case anyway. + (zoo*(-log(tan(x/2) - 1) + log(tan(x/2) + 1)), Eq(a, 0) & Eq(b, 0)), + (log(tan(x/2))/a, Eq(b, 0)), + (-I/(-I*b*sin(x) + b*cos(x)), Eq(a, -I*b)), + (I/(I*b*sin(x) + b*cos(x)), Eq(a, I*b)), + (Fpos, True), + ) + assert integrate(f, x) == F + + ap, bp = symbols('a, b', positive=True) + rep = {a: ap, b: bp} + assert integrate(f.subs(rep), x) == Fpos.subs(rep) + + +def test_issue_23566(): + i = integrate(1/sqrt(x**2-1), (x, -2, -1)) + assert i == -log(2 - sqrt(3)) + assert math.isclose(i.n(), 1.31695789692482) + + +def test_pr_23583(): + # This result from meijerg is wrong. Check whether new result is correct when this test fail. + assert integrate(1/sqrt((x - I)**2-1)) == Piecewise((acosh(x - I), Abs((x - I)**2) > 1), (-I*asin(x - I), True)) + + +def test_issue_7264(): + assert integrate(exp(x)*sqrt(1 + exp(2*x))) == sqrt(exp(2*x) + 1)*exp(x)/2 + asinh(exp(x))/2 + + +def test_issue_11254a(): + assert integrate(sech(x), (x, 0, 1)) == 2*atan(tanh(S.Half)) + + +def test_issue_11254b(): + assert integrate(csch(x), x) == log(tanh(x/2)) + assert integrate(csch(x), (x, 0, 1)) == oo + + +def test_issue_11254d(): + # (sech(x)**2).rewrite(sinh) + assert integrate(-1/sinh(x + I*pi/2, evaluate=False)**2, x) == -2/(exp(2*x) + 1) + assert integrate(cosh(x)**(-2), x) == 2*tanh(x/2)/(tanh(x/2)**2 + 1) + + +def test_issue_22863(): + i = integrate((3*x**3-x**2+2*x-4)/sqrt(x**2-3*x+2), (x, 0, 1)) + assert i == -101*sqrt(2)/8 - 135*log(3 - 2*sqrt(2))/16 + assert math.isclose(i.n(), -2.98126694400554) + + +def test_issue_9723(): + assert integrate(sqrt(x + sqrt(x))) == \ + 2*sqrt(sqrt(x) + x)*(sqrt(x)/12 + x/3 - S(1)/8) + log(2*sqrt(x) + 2*sqrt(sqrt(x) + x) + 1)/8 + assert integrate(sqrt(2*x+3+sqrt(4*x+5))**3) == \ + sqrt(2*x + sqrt(4*x + 5) + 3) * \ + (9*x/10 + 11*(4*x + 5)**(S(3)/2)/40 + sqrt(4*x + 5)/40 + (4*x + 5)**2/10 + S(11)/10)/2 + + +def test_issue_23704(): + # XXX: This is testing that an exception is not raised in risch Ideally + # manualintegrate (manual=True) would be able to compute this but + # manualintegrate is very slow for this example so we don't test that here. + assert (integrate(log(x)/x**2/(c*x**2+b*x+a),x, risch=True) + == NonElementaryIntegral(log(x)/(a*x**2 + b*x**3 + c*x**4), x)) + + +def test_exp_substitution(): + assert integrate(1/sqrt(1-exp(2*x))) == log(sqrt(1 - exp(2*x)) - 1)/2 - log(sqrt(1 - exp(2*x)) + 1)/2 + + +def test_hyperbolic(): + assert integrate(coth(x)) == x - log(tanh(x) + 1) + log(tanh(x)) + assert integrate(sech(x)) == 2*atan(tanh(x/2)) + assert integrate(csch(x)) == log(tanh(x/2)) + + +def test_nested_pow(): + assert integrate(sqrt(x**2)) == x*sqrt(x**2)/2 + assert integrate(sqrt(x**(S(5)/3))) == 6*x*sqrt(x**(S(5)/3))/11 + assert integrate(1/sqrt(x**2)) == x*log(x)/sqrt(x**2) + assert integrate(x*sqrt(x**(-4))) == x**2*sqrt(x**-4)*log(x) + + +def test_sqrt_quadratic(): + assert integrate(1/sqrt(3*x**2+4*x+5)) == sqrt(3)*asinh(3*sqrt(11)*(x + S(2)/3)/11)/3 + assert integrate(1/sqrt(-3*x**2+4*x+5)) == sqrt(3)*asin(3*sqrt(19)*(x - S(2)/3)/19)/3 + assert integrate(1/sqrt(3*x**2+4*x-5)) == sqrt(3)*log(6*x + 2*sqrt(3)*sqrt(3*x**2 + 4*x - 5) + 4)/3 + assert integrate(1/sqrt(4*x**2-4*x+1)) == (x - S.Half)*log(x - S.Half)/(2*sqrt((x - S.Half)**2)) + assert integrate(1/sqrt(a+b*x+c*x**2), x) == \ + Piecewise((log(b + 2*sqrt(c)*sqrt(a + b*x + c*x**2) + 2*c*x)/sqrt(c), Ne(c, 0) & Ne(a - b**2/(4*c), 0)), + ((b/(2*c) + x)*log(b/(2*c) + x)/sqrt(c*(b/(2*c) + x)**2), Ne(c, 0)), + (2*sqrt(a + b*x)/b, Ne(b, 0)), (x/sqrt(a), True)) + + assert integrate((7*x+6)/sqrt(3*x**2+4*x+5)) == \ + 7*sqrt(3*x**2 + 4*x + 5)/3 + 4*sqrt(3)*asinh(3*sqrt(11)*(x + S(2)/3)/11)/9 + assert integrate((7*x+6)/sqrt(-3*x**2+4*x+5)) == \ + -7*sqrt(-3*x**2 + 4*x + 5)/3 + 32*sqrt(3)*asin(3*sqrt(19)*(x - S(2)/3)/19)/9 + assert integrate((7*x+6)/sqrt(3*x**2+4*x-5)) == \ + 7*sqrt(3*x**2 + 4*x - 5)/3 + 4*sqrt(3)*log(6*x + 2*sqrt(3)*sqrt(3*x**2 + 4*x - 5) + 4)/9 + assert integrate((d+e*x)/sqrt(a+b*x+c*x**2), x) == \ + Piecewise(((-b*e/(2*c) + d) * + Piecewise((log(b + 2*sqrt(c)*sqrt(a + b*x + c*x**2) + 2*c*x)/sqrt(c), Ne(a - b**2/(4*c), 0)), + ((b/(2*c) + x)*log(b/(2*c) + x)/sqrt(c*(b/(2*c) + x)**2), True)) + + e*sqrt(a + b*x + c*x**2)/c, Ne(c, 0)), + ((2*d*sqrt(a + b*x) + 2*e*(-a*sqrt(a + b*x) + (a + b*x)**(S(3)/2)/3)/b)/b, Ne(b, 0)), + ((d*x + e*x**2/2)/sqrt(a), True)) + + assert integrate((3*x**3-x**2+2*x-4)/sqrt(x**2-3*x+2)) == \ + sqrt(x**2 - 3*x + 2)*(x**2 + 13*x/4 + S(101)/8) + 135*log(2*x + 2*sqrt(x**2 - 3*x + 2) - 3)/16 + + assert integrate(sqrt(53225*x**2-66732*x+23013)) == \ + (x/2 - S(16683)/53225)*sqrt(53225*x**2 - 66732*x + 23013) + \ + 111576969*sqrt(2129)*asinh(53225*x/10563 - S(11122)/3521)/1133160250 + assert integrate(sqrt(a+b*x+c*x**2), x) == \ + Piecewise(((a/2 - b**2/(8*c)) * + Piecewise((log(b + 2*sqrt(c)*sqrt(a + b*x + c*x**2) + 2*c*x)/sqrt(c), Ne(a - b**2/(4*c), 0)), + ((b/(2*c) + x)*log(b/(2*c) + x)/sqrt(c*(b/(2*c) + x)**2), True)) + + (b/(4*c) + x/2)*sqrt(a + b*x + c*x**2), Ne(c, 0)), + (2*(a + b*x)**(S(3)/2)/(3*b), Ne(b, 0)), + (sqrt(a)*x, True)) + + assert integrate(x*sqrt(x**2+2*x+4)) == \ + (x**2/3 + x/6 + S(5)/6)*sqrt(x**2 + 2*x + 4) - 3*asinh(sqrt(3)*(x + 1)/3)/2 + + +def test_mul_pow_derivative(): + assert integrate(x*sec(x)*tan(x)) == x*sec(x) - log(tan(x) + sec(x)) + assert integrate(x*sec(x)**2, x) == x*tan(x) + log(cos(x)) + assert integrate(x**3*Derivative(f(x), (x, 4))) == \ + x**3*Derivative(f(x), (x, 3)) - 3*x**2*Derivative(f(x), (x, 2)) + 6*x*Derivative(f(x), x) - 6*f(x) + + +def test_issue_20782(): + fun1 = Piecewise((0, x < 0.0), (1, True)) + fun2 = -Piecewise((0, x < 1.0), (1, True)) + fun_sum = fun1 + fun2 + L = (x, -float('Inf'), 1) + + assert integrate(fun1, L) == 1 + assert integrate(fun2, L) == 0 + assert integrate(-fun1, L) == -1 + assert integrate(-fun2, L) == 0 + assert integrate(fun_sum, L) == 1. + assert integrate(-fun_sum, L) == -1. + + +def test_issue_20781(): + P = lambda a: Piecewise((0, x < a), (1, x >= a)) + f = lambda a: P(int(a)) + P(float(a)) + L = (x, -float('Inf'), x) + f1 = integrate(f(1), L) + assert f1 == 2*x - Min(1.0, x) - Min(x, Max(1.0, 1, evaluate=False)) + # XXX is_zero is True for S(0) and Float(0) and this is baked into + # the code more deeply than the issue of Float(0) != S(0) + assert integrate(f(0), (x, -float('Inf'), x) + ) == 2*x - 2*Min(0, x) + + +@slow +def test_issue_19427(): + # + x = Symbol("x") + + # Have always been okay: + assert integrate((x ** 4) * sqrt(1 - x ** 2), (x, -1, 1)) == pi / 16 + assert integrate((-2 * x ** 2) * sqrt(1 - x ** 2), (x, -1, 1)) == -pi / 4 + assert integrate((1) * sqrt(1 - x ** 2), (x, -1, 1)) == pi / 2 + + # Sum of the above, used to incorrectly return 0 for a while: + assert integrate((x ** 4 - 2 * x ** 2 + 1) * sqrt(1 - x ** 2), (x, -1, 1)) == 5 * pi / 16 + + +def test_issue_23942(): + I1 = Integral(1/sqrt(a*(1 + x)**3 + (1 + x)**2), (x, 0, z)) + assert I1.series(a, 1, n=1) == Integral(1/sqrt(x**3 + 4*x**2 + 5*x + 2), (x, 0, z)) + O(a - 1, (a, 1)) + I2 = Integral(1/sqrt(a*(4 - x)**4 + (5 + x)**2), (x, 0, z)) + assert I2.series(a, 2, n=1) == Integral(1/sqrt(2*x**4 - 32*x**3 + 193*x**2 - 502*x + 537), (x, 0, z)) + O(a - 2, (a, 2)) + + +def test_issue_25886(): + # https://github.com/sympy/sympy/issues/25886 + f = (1-x)*exp(0.937098661j*x) + F_exp = (1.0*(-1.0671234968289*I*y + + 1.13875255748434 + + 1.0671234968289*I)*exp(0.937098661*I*y) + - 1.13875255748434*exp(0.937098661*I)) + F = integrate(f, (x, y, 1.0)) + assert F.is_same(F_exp, math.isclose) + + +def test_old_issues(): + # https://github.com/sympy/sympy/issues/5212 + I1 = integrate(cos(log(x**2))/x) + assert I1 == sin(log(x**2))/2 + # https://github.com/sympy/sympy/issues/5462 + I2 = integrate(1/(x**2+y**2)**(Rational(3,2)),x) + assert I2 == x/(y**3*sqrt(x**2/y**2 + 1)) + # https://github.com/sympy/sympy/issues/6278 + I3 = integrate(1/(cos(x)+2),(x,0,2*pi)) + assert I3 == 2*sqrt(3)*pi/3 + + +def test_integral_issue_26566(): + # Define the symbols + x = symbols('x', real=True) + a = symbols('a', real=True, positive=True) + + # Define the integral expression + integral_expr = sin(a * (x + pi))**2 + symbolic_result = integrate(integral_expr, (x, -pi, -pi/2)) + + # Known correct result + correct_result = pi / 4 + + # Substitute a specific value for 'a' to evaluate both results + a_value = 1 + numeric_symbolic_result = symbolic_result.subs(a, a_value).evalf() + numeric_correct_result = correct_result.evalf() + + # Assert that the symbolic result matches the correct value + assert simplify(numeric_symbolic_result - numeric_correct_result) == 0 + + +def test_definite_integral_with_floats_issue_27231(): + # Define the symbol and the integral expression + x = symbols('x', real=True) + integral_expr = sqrt(1 - 0.5625 * (x + 0.333333333333333) ** 2) + + # Perform the definite integral with the known limits + result_symbolic = integrate(integral_expr, (x, -1, 1)) + result_numeric = result_symbolic.evalf() + + # Expected result with higher precision + expected_result = sqrt(3) / 6 + 4 * pi / 9 + + # Verify that the result is approximately equal within a larger tolerance + assert abs(result_numeric - expected_result.evalf()) < 1e-8 + + +def test_issue_27374(): + #https://github.com/sympy/sympy/issues/27374 + r = sqrt(x**2 + z**2) + u = erf(a*r/sqrt(2))/r + Ec = diff(u, z, z).subs([(x, sqrt(b*b-z*z))]) + expected_result = -2*sqrt(2)*b*a**3*exp(-b**2*a**2/2)/(3*sqrt(pi)) + assert simplify(integrate(Ec, (z, -b, b))) == expected_result diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_intpoly.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_intpoly.py new file mode 100644 index 0000000000000000000000000000000000000000..ddbaad1fbdeca53ccab8e8b22758a6ad2d89836e --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_intpoly.py @@ -0,0 +1,627 @@ +from sympy.functions.elementary.complexes import Abs +from sympy.functions.elementary.miscellaneous import sqrt + +from sympy.core import S, Rational + +from sympy.integrals.intpoly import (decompose, best_origin, distance_to_side, + polytope_integrate, point_sort, + hyperplane_parameters, main_integrate3d, + main_integrate, polygon_integrate, + lineseg_integrate, integration_reduction, + integration_reduction_dynamic, is_vertex) + +from sympy.geometry.line import Segment2D +from sympy.geometry.polygon import Polygon +from sympy.geometry.point import Point, Point2D +from sympy.abc import x, y, z + +from sympy.testing.pytest import slow + + +def test_decompose(): + assert decompose(x) == {1: x} + assert decompose(x**2) == {2: x**2} + assert decompose(x*y) == {2: x*y} + assert decompose(x + y) == {1: x + y} + assert decompose(x**2 + y) == {1: y, 2: x**2} + assert decompose(8*x**2 + 4*y + 7) == {0: 7, 1: 4*y, 2: 8*x**2} + assert decompose(x**2 + 3*y*x) == {2: x**2 + 3*x*y} + assert decompose(9*x**2 + y + 4*x + x**3 + y**2*x + 3) ==\ + {0: 3, 1: 4*x + y, 2: 9*x**2, 3: x**3 + x*y**2} + + assert decompose(x, True) == {x} + assert decompose(x ** 2, True) == {x**2} + assert decompose(x * y, True) == {x * y} + assert decompose(x + y, True) == {x, y} + assert decompose(x ** 2 + y, True) == {y, x ** 2} + assert decompose(8 * x ** 2 + 4 * y + 7, True) == {7, 4*y, 8*x**2} + assert decompose(x ** 2 + 3 * y * x, True) == {x ** 2, 3 * x * y} + assert decompose(9 * x ** 2 + y + 4 * x + x ** 3 + y ** 2 * x + 3, True) == \ + {3, y, 4*x, 9*x**2, x*y**2, x**3} + + +def test_best_origin(): + expr1 = y ** 2 * x ** 5 + y ** 5 * x ** 7 + 7 * x + x ** 12 + y ** 7 * x + + l1 = Segment2D(Point(0, 3), Point(1, 1)) + l2 = Segment2D(Point(S(3) / 2, 0), Point(S(3) / 2, 3)) + l3 = Segment2D(Point(0, S(3) / 2), Point(3, S(3) / 2)) + l4 = Segment2D(Point(0, 2), Point(2, 0)) + l5 = Segment2D(Point(0, 2), Point(1, 1)) + l6 = Segment2D(Point(2, 0), Point(1, 1)) + + assert best_origin((2, 1), 3, l1, expr1) == (0, 3) + # XXX: Should these return exact Rational output? Maybe best_origin should + # sympify its arguments... + assert best_origin((2, 0), 3, l2, x ** 7) == (1.5, 0) + assert best_origin((0, 2), 3, l3, x ** 7) == (0, 1.5) + assert best_origin((1, 1), 2, l4, x ** 7 * y ** 3) == (0, 2) + assert best_origin((1, 1), 2, l4, x ** 3 * y ** 7) == (2, 0) + assert best_origin((1, 1), 2, l5, x ** 2 * y ** 9) == (0, 2) + assert best_origin((1, 1), 2, l6, x ** 9 * y ** 2) == (2, 0) + + +@slow +def test_polytope_integrate(): + # Convex 2-Polytopes + # Vertex representation + assert polytope_integrate(Polygon(Point(0, 0), Point(0, 2), + Point(4, 0)), 1) == 4 + assert polytope_integrate(Polygon(Point(0, 0), Point(0, 1), + Point(1, 1), Point(1, 0)), x * y) ==\ + Rational(1, 4) + assert polytope_integrate(Polygon(Point(0, 3), Point(5, 3), Point(1, 1)), + 6*x**2 - 40*y) == Rational(-935, 3) + + assert polytope_integrate(Polygon(Point(0, 0), Point(0, sqrt(3)), + Point(sqrt(3), sqrt(3)), + Point(sqrt(3), 0)), 1) == 3 + + hexagon = Polygon(Point(0, 0), Point(-sqrt(3) / 2, S.Half), + Point(-sqrt(3) / 2, S(3) / 2), Point(0, 2), + Point(sqrt(3) / 2, S(3) / 2), Point(sqrt(3) / 2, S.Half)) + + assert polytope_integrate(hexagon, 1) == S(3*sqrt(3)) / 2 + + # Hyperplane representation + assert polytope_integrate([((-1, 0), 0), ((1, 2), 4), + ((0, -1), 0)], 1) == 4 + assert polytope_integrate([((-1, 0), 0), ((0, 1), 1), + ((1, 0), 1), ((0, -1), 0)], x * y) == Rational(1, 4) + assert polytope_integrate([((0, 1), 3), ((1, -2), -1), + ((-2, -1), -3)], 6*x**2 - 40*y) == Rational(-935, 3) + assert polytope_integrate([((-1, 0), 0), ((0, sqrt(3)), 3), + ((sqrt(3), 0), 3), ((0, -1), 0)], 1) == 3 + + hexagon = [((Rational(-1, 2), -sqrt(3) / 2), 0), + ((-1, 0), sqrt(3) / 2), + ((Rational(-1, 2), sqrt(3) / 2), sqrt(3)), + ((S.Half, sqrt(3) / 2), sqrt(3)), + ((1, 0), sqrt(3) / 2), + ((S.Half, -sqrt(3) / 2), 0)] + assert polytope_integrate(hexagon, 1) == S(3*sqrt(3)) / 2 + + # Non-convex polytopes + # Vertex representation + assert polytope_integrate(Polygon(Point(-1, -1), Point(-1, 1), + Point(1, 1), Point(0, 0), + Point(1, -1)), 1) == 3 + assert polytope_integrate(Polygon(Point(-1, -1), Point(-1, 1), + Point(0, 0), Point(1, 1), + Point(1, -1), Point(0, 0)), 1) == 2 + # Hyperplane representation + assert polytope_integrate([((-1, 0), 1), ((0, 1), 1), ((1, -1), 0), + ((1, 1), 0), ((0, -1), 1)], 1) == 3 + assert polytope_integrate([((-1, 0), 1), ((1, 1), 0), ((-1, 1), 0), + ((1, 0), 1), ((-1, -1), 0), + ((1, -1), 0)], 1) == 2 + + # Tests for 2D polytopes mentioned in Chin et al(Page 10): + # http://dilbert.engr.ucdavis.edu/~suku/quadrature/cls-integration.pdf + fig1 = Polygon(Point(1.220, -0.827), Point(-1.490, -4.503), + Point(-3.766, -1.622), Point(-4.240, -0.091), + Point(-3.160, 4), Point(-0.981, 4.447), + Point(0.132, 4.027)) + assert polytope_integrate(fig1, x**2 + x*y + y**2) ==\ + S(2031627344735367)/(8*10**12) + + fig2 = Polygon(Point(4.561, 2.317), Point(1.491, -1.315), + Point(-3.310, -3.164), Point(-4.845, -3.110), + Point(-4.569, 1.867)) + assert polytope_integrate(fig2, x**2 + x*y + y**2) ==\ + S(517091313866043)/(16*10**11) + + fig3 = Polygon(Point(-2.740, -1.888), Point(-3.292, 4.233), + Point(-2.723, -0.697), Point(-0.643, -3.151)) + assert polytope_integrate(fig3, x**2 + x*y + y**2) ==\ + S(147449361647041)/(8*10**12) + + fig4 = Polygon(Point(0.211, -4.622), Point(-2.684, 3.851), + Point(0.468, 4.879), Point(4.630, -1.325), + Point(-0.411, -1.044)) + assert polytope_integrate(fig4, x**2 + x*y + y**2) ==\ + S(180742845225803)/(10**12) + + # Tests for many polynomials with maximum degree given(2D case). + tri = Polygon(Point(0, 3), Point(5, 3), Point(1, 1)) + polys = [] + expr1 = x**9*y + x**7*y**3 + 2*x**2*y**8 + expr2 = x**6*y**4 + x**5*y**5 + 2*y**10 + expr3 = x**10 + x**9*y + x**8*y**2 + x**5*y**5 + polys.extend((expr1, expr2, expr3)) + result_dict = polytope_integrate(tri, polys, max_degree=10) + assert result_dict[expr1] == Rational(615780107, 594) + assert result_dict[expr2] == Rational(13062161, 27) + assert result_dict[expr3] == Rational(1946257153, 924) + + tri = Polygon(Point(0, 3), Point(5, 3), Point(1, 1)) + expr1 = x**7*y**1 + 2*x**2*y**6 + expr2 = x**6*y**4 + x**5*y**5 + 2*y**10 + expr3 = x**10 + x**9*y + x**8*y**2 + x**5*y**5 + polys.extend((expr1, expr2, expr3)) + assert polytope_integrate(tri, polys, max_degree=9) == \ + {x**7*y + 2*x**2*y**6: Rational(489262, 9)} + + # Tests when all integral of all monomials up to a max_degree is to be + # calculated. + assert polytope_integrate(Polygon(Point(0, 0), Point(0, 1), + Point(1, 1), Point(1, 0)), + max_degree=4) == {0: 0, 1: 1, x: S.Half, + x ** 2 * y ** 2: S.One / 9, + x ** 4: S.One / 5, + y ** 4: S.One / 5, + y: S.Half, + x * y ** 2: S.One / 6, + y ** 2: S.One / 3, + x ** 3: S.One / 4, + x ** 2 * y: S.One / 6, + x ** 3 * y: S.One / 8, + x * y: S.One / 4, + y ** 3: S.One / 4, + x ** 2: S.One / 3, + x * y ** 3: S.One / 8} + + # Tests for 3D polytopes + cube1 = [[(0, 0, 0), (0, 6, 6), (6, 6, 6), (3, 6, 0), + (0, 6, 0), (6, 0, 6), (3, 0, 0), (0, 0, 6)], + [1, 2, 3, 4], [3, 2, 5, 6], [1, 7, 5, 2], [0, 6, 5, 7], + [1, 4, 0, 7], [0, 4, 3, 6]] + assert polytope_integrate(cube1, 1) == S(162) + + # 3D Test cases in Chin et al(2015) + cube2 = [[(0, 0, 0), (0, 0, 5), (0, 5, 0), (0, 5, 5), (5, 0, 0), + (5, 0, 5), (5, 5, 0), (5, 5, 5)], + [3, 7, 6, 2], [1, 5, 7, 3], [5, 4, 6, 7], [0, 4, 5, 1], + [2, 0, 1, 3], [2, 6, 4, 0]] + + cube3 = [[(0, 0, 0), (5, 0, 0), (5, 4, 0), (3, 2, 0), (3, 5, 0), + (0, 5, 0), (0, 0, 5), (5, 0, 5), (5, 4, 5), (3, 2, 5), + (3, 5, 5), (0, 5, 5)], + [6, 11, 5, 0], [1, 7, 6, 0], [5, 4, 3, 2, 1, 0], [11, 10, 4, 5], + [10, 9, 3, 4], [9, 8, 2, 3], [8, 7, 1, 2], [7, 8, 9, 10, 11, 6]] + + cube4 = [[(0, 0, 0), (1, 0, 0), (0, 1, 0), (0, 0, 1), + (S.One / 4, S.One / 4, S.One / 4)], + [0, 2, 1], [1, 3, 0], [4, 2, 3], [4, 3, 1], + [0, 1, 2], [2, 4, 1], [0, 3, 2]] + + assert polytope_integrate(cube2, x ** 2 + y ** 2 + x * y + z ** 2) ==\ + Rational(15625, 4) + assert polytope_integrate(cube3, x ** 2 + y ** 2 + x * y + z ** 2) ==\ + S(33835) / 12 + assert polytope_integrate(cube4, x ** 2 + y ** 2 + x * y + z ** 2) ==\ + S(37) / 960 + + # Test cases from Mathematica's PolyhedronData library + octahedron = [[(S.NegativeOne / sqrt(2), 0, 0), (0, S.One / sqrt(2), 0), + (0, 0, S.NegativeOne / sqrt(2)), (0, 0, S.One / sqrt(2)), + (0, S.NegativeOne / sqrt(2), 0), (S.One / sqrt(2), 0, 0)], + [3, 4, 5], [3, 5, 1], [3, 1, 0], [3, 0, 4], [4, 0, 2], + [4, 2, 5], [2, 0, 1], [5, 2, 1]] + + assert polytope_integrate(octahedron, 1) == sqrt(2) / 3 + + great_stellated_dodecahedron =\ + [[(-0.32491969623290634095, 0, 0.42532540417601993887), + (0.32491969623290634095, 0, -0.42532540417601993887), + (-0.52573111211913359231, 0, 0.10040570794311363956), + (0.52573111211913359231, 0, -0.10040570794311363956), + (-0.10040570794311363956, -0.3090169943749474241, 0.42532540417601993887), + (-0.10040570794311363956, 0.30901699437494742410, 0.42532540417601993887), + (0.10040570794311363956, -0.3090169943749474241, -0.42532540417601993887), + (0.10040570794311363956, 0.30901699437494742410, -0.42532540417601993887), + (-0.16245984811645317047, -0.5, 0.10040570794311363956), + (-0.16245984811645317047, 0.5, 0.10040570794311363956), + (0.16245984811645317047, -0.5, -0.10040570794311363956), + (0.16245984811645317047, 0.5, -0.10040570794311363956), + (-0.42532540417601993887, -0.3090169943749474241, -0.10040570794311363956), + (-0.42532540417601993887, 0.30901699437494742410, -0.10040570794311363956), + (-0.26286555605956679615, 0.1909830056250525759, -0.42532540417601993887), + (-0.26286555605956679615, -0.1909830056250525759, -0.42532540417601993887), + (0.26286555605956679615, 0.1909830056250525759, 0.42532540417601993887), + (0.26286555605956679615, -0.1909830056250525759, 0.42532540417601993887), + (0.42532540417601993887, -0.3090169943749474241, 0.10040570794311363956), + (0.42532540417601993887, 0.30901699437494742410, 0.10040570794311363956)], + [12, 3, 0, 6, 16], [17, 7, 0, 3, 13], + [9, 6, 0, 7, 8], [18, 2, 1, 4, 14], + [15, 5, 1, 2, 19], [11, 4, 1, 5, 10], + [8, 19, 2, 18, 9], [10, 13, 3, 12, 11], + [16, 14, 4, 11, 12], [13, 10, 5, 15, 17], + [14, 16, 6, 9, 18], [19, 8, 7, 17, 15]] + # Actual volume is : 0.163118960624632 + assert Abs(polytope_integrate(great_stellated_dodecahedron, 1) -\ + 0.163118960624632) < 1e-12 + + expr = x **2 + y ** 2 + z ** 2 + octahedron_five_compound = [[(0, -0.7071067811865475244, 0), + (0, 0.70710678118654752440, 0), + (0.1148764602736805918, + -0.35355339059327376220, -0.60150095500754567366), + (0.1148764602736805918, 0.35355339059327376220, + -0.60150095500754567366), + (0.18587401723009224507, + -0.57206140281768429760, 0.37174803446018449013), + (0.18587401723009224507, 0.57206140281768429760, + 0.37174803446018449013), + (0.30075047750377283683, -0.21850801222441053540, + 0.60150095500754567366), + (0.30075047750377283683, 0.21850801222441053540, + 0.60150095500754567366), + (0.48662449473386508189, -0.35355339059327376220, + -0.37174803446018449013), + (0.48662449473386508189, 0.35355339059327376220, + -0.37174803446018449013), + (-0.60150095500754567366, 0, -0.37174803446018449013), + (-0.30075047750377283683, -0.21850801222441053540, + -0.60150095500754567366), + (-0.30075047750377283683, 0.21850801222441053540, + -0.60150095500754567366), + (0.60150095500754567366, 0, 0.37174803446018449013), + (0.4156269377774534286, -0.57206140281768429760, 0), + (0.4156269377774534286, 0.57206140281768429760, 0), + (0.37174803446018449013, 0, -0.60150095500754567366), + (-0.4156269377774534286, -0.57206140281768429760, 0), + (-0.4156269377774534286, 0.57206140281768429760, 0), + (-0.67249851196395732696, -0.21850801222441053540, 0), + (-0.67249851196395732696, 0.21850801222441053540, 0), + (0.67249851196395732696, -0.21850801222441053540, 0), + (0.67249851196395732696, 0.21850801222441053540, 0), + (-0.37174803446018449013, 0, 0.60150095500754567366), + (-0.48662449473386508189, -0.35355339059327376220, + 0.37174803446018449013), + (-0.48662449473386508189, 0.35355339059327376220, + 0.37174803446018449013), + (-0.18587401723009224507, -0.57206140281768429760, + -0.37174803446018449013), + (-0.18587401723009224507, 0.57206140281768429760, + -0.37174803446018449013), + (-0.11487646027368059176, -0.35355339059327376220, + 0.60150095500754567366), + (-0.11487646027368059176, 0.35355339059327376220, + 0.60150095500754567366)], + [0, 10, 16], [23, 10, 0], [16, 13, 0], + [0, 13, 23], [16, 10, 1], [1, 10, 23], + [1, 13, 16], [23, 13, 1], [2, 4, 19], + [22, 4, 2], [2, 19, 27], [27, 22, 2], + [20, 5, 3], [3, 5, 21], [26, 20, 3], + [3, 21, 26], [29, 19, 4], [4, 22, 29], + [5, 20, 28], [28, 21, 5], [6, 8, 15], + [17, 8, 6], [6, 15, 25], [25, 17, 6], + [14, 9, 7], [7, 9, 18], [24, 14, 7], + [7, 18, 24], [8, 12, 15], [17, 12, 8], + [14, 11, 9], [9, 11, 18], [11, 14, 24], + [24, 18, 11], [25, 15, 12], [12, 17, 25], + [29, 27, 19], [20, 26, 28], [28, 26, 21], + [22, 27, 29]] + assert Abs(polytope_integrate(octahedron_five_compound, expr)) - 0.353553\ + < 1e-6 + + cube_five_compound = [[(-0.1624598481164531631, -0.5, -0.6881909602355867691), + (-0.1624598481164531631, 0.5, -0.6881909602355867691), + (0.1624598481164531631, -0.5, 0.68819096023558676910), + (0.1624598481164531631, 0.5, 0.68819096023558676910), + (-0.52573111211913359231, 0, -0.6881909602355867691), + (0.52573111211913359231, 0, 0.68819096023558676910), + (-0.26286555605956679615, -0.8090169943749474241, + -0.1624598481164531631), + (-0.26286555605956679615, 0.8090169943749474241, + -0.1624598481164531631), + (0.26286555605956680301, -0.8090169943749474241, + 0.1624598481164531631), + (0.26286555605956680301, 0.8090169943749474241, + 0.1624598481164531631), + (-0.42532540417601993887, -0.3090169943749474241, + 0.68819096023558676910), + (-0.42532540417601993887, 0.30901699437494742410, + 0.68819096023558676910), + (0.42532540417601996609, -0.3090169943749474241, + -0.6881909602355867691), + (0.42532540417601996609, 0.30901699437494742410, + -0.6881909602355867691), + (-0.6881909602355867691, -0.5, 0.1624598481164531631), + (-0.6881909602355867691, 0.5, 0.1624598481164531631), + (0.68819096023558676910, -0.5, -0.1624598481164531631), + (0.68819096023558676910, 0.5, -0.1624598481164531631), + (-0.85065080835203998877, 0, -0.1624598481164531631), + (0.85065080835203993218, 0, 0.1624598481164531631)], + [18, 10, 3, 7], [13, 19, 8, 0], [18, 0, 8, 10], + [3, 19, 13, 7], [18, 7, 13, 0], [8, 19, 3, 10], + [6, 2, 11, 18], [1, 9, 19, 12], [11, 9, 1, 18], + [6, 12, 19, 2], [1, 12, 6, 18], [11, 2, 19, 9], + [4, 14, 11, 7], [17, 5, 8, 12], [4, 12, 8, 14], + [11, 5, 17, 7], [4, 7, 17, 12], [8, 5, 11, 14], + [6, 10, 15, 4], [13, 9, 5, 16], [15, 9, 13, 4], + [6, 16, 5, 10], [13, 16, 6, 4], [15, 10, 5, 9], + [14, 15, 1, 0], [16, 17, 3, 2], [14, 2, 3, 15], + [1, 17, 16, 0], [14, 0, 16, 2], [3, 17, 1, 15]] + assert Abs(polytope_integrate(cube_five_compound, expr) - 1.25) < 1e-12 + + echidnahedron = [[(0, 0, -2.4898982848827801995), + (0, 0, 2.4898982848827802734), + (0, -4.2360679774997896964, -2.4898982848827801995), + (0, -4.2360679774997896964, 2.4898982848827802734), + (0, 4.2360679774997896964, -2.4898982848827801995), + (0, 4.2360679774997896964, 2.4898982848827802734), + (-4.0287400534704067567, -1.3090169943749474241, -2.4898982848827801995), + (-4.0287400534704067567, -1.3090169943749474241, 2.4898982848827802734), + (-4.0287400534704067567, 1.3090169943749474241, -2.4898982848827801995), + (-4.0287400534704067567, 1.3090169943749474241, 2.4898982848827802734), + (4.0287400534704069747, -1.3090169943749474241, -2.4898982848827801995), + (4.0287400534704069747, -1.3090169943749474241, 2.4898982848827802734), + (4.0287400534704069747, 1.3090169943749474241, -2.4898982848827801995), + (4.0287400534704069747, 1.3090169943749474241, 2.4898982848827802734), + (-2.4898982848827801995, -3.4270509831248422723, -2.4898982848827801995), + (-2.4898982848827801995, -3.4270509831248422723, 2.4898982848827802734), + (-2.4898982848827801995, 3.4270509831248422723, -2.4898982848827801995), + (-2.4898982848827801995, 3.4270509831248422723, 2.4898982848827802734), + (2.4898982848827802734, -3.4270509831248422723, -2.4898982848827801995), + (2.4898982848827802734, -3.4270509831248422723, 2.4898982848827802734), + (2.4898982848827802734, 3.4270509831248422723, -2.4898982848827801995), + (2.4898982848827802734, 3.4270509831248422723, 2.4898982848827802734), + (-4.7169310137059934362, -0.8090169943749474241, -1.1135163644116066184), + (-4.7169310137059934362, 0.8090169943749474241, -1.1135163644116066184), + (4.7169310137059937438, -0.8090169943749474241, 1.11351636441160673519), + (4.7169310137059937438, 0.8090169943749474241, 1.11351636441160673519), + (-4.2916056095299737777, -2.1180339887498948482, 1.11351636441160673519), + (-4.2916056095299737777, 2.1180339887498948482, 1.11351636441160673519), + (4.2916056095299737777, -2.1180339887498948482, -1.1135163644116066184), + (4.2916056095299737777, 2.1180339887498948482, -1.1135163644116066184), + (-3.6034146492943870399, 0, -3.3405490932348205213), + (3.6034146492943870399, 0, 3.3405490932348202056), + (-3.3405490932348205213, -3.4270509831248422723, 1.11351636441160673519), + (-3.3405490932348205213, 3.4270509831248422723, 1.11351636441160673519), + (3.3405490932348202056, -3.4270509831248422723, -1.1135163644116066184), + (3.3405490932348202056, 3.4270509831248422723, -1.1135163644116066184), + (-2.9152236890588002395, -2.1180339887498948482, 3.3405490932348202056), + (-2.9152236890588002395, 2.1180339887498948482, 3.3405490932348202056), + (2.9152236890588002395, -2.1180339887498948482, -3.3405490932348205213), + (2.9152236890588002395, 2.1180339887498948482, -3.3405490932348205213), + (-2.2270327288232132368, 0, -1.1135163644116066184), + (-2.2270327288232132368, -4.2360679774997896964, -1.1135163644116066184), + (-2.2270327288232132368, 4.2360679774997896964, -1.1135163644116066184), + (2.2270327288232134704, 0, 1.11351636441160673519), + (2.2270327288232134704, -4.2360679774997896964, 1.11351636441160673519), + (2.2270327288232134704, 4.2360679774997896964, 1.11351636441160673519), + (-1.8017073246471935200, -1.3090169943749474241, 1.11351636441160673519), + (-1.8017073246471935200, 1.3090169943749474241, 1.11351636441160673519), + (1.8017073246471935043, -1.3090169943749474241, -1.1135163644116066184), + (1.8017073246471935043, 1.3090169943749474241, -1.1135163644116066184), + (-1.3763819204711735382, 0, -4.7169310137059934362), + (-1.3763819204711735382, 0, 0.26286555605956679615), + (1.37638192047117353821, 0, 4.7169310137059937438), + (1.37638192047117353821, 0, -0.26286555605956679615), + (-1.1135163644116066184, -3.4270509831248422723, -3.3405490932348205213), + (-1.1135163644116066184, -0.8090169943749474241, 4.7169310137059937438), + (-1.1135163644116066184, -0.8090169943749474241, -0.26286555605956679615), + (-1.1135163644116066184, 0.8090169943749474241, 4.7169310137059937438), + (-1.1135163644116066184, 0.8090169943749474241, -0.26286555605956679615), + (-1.1135163644116066184, 3.4270509831248422723, -3.3405490932348205213), + (1.11351636441160673519, -3.4270509831248422723, 3.3405490932348202056), + (1.11351636441160673519, -0.8090169943749474241, -4.7169310137059934362), + (1.11351636441160673519, -0.8090169943749474241, 0.26286555605956679615), + (1.11351636441160673519, 0.8090169943749474241, -4.7169310137059934362), + (1.11351636441160673519, 0.8090169943749474241, 0.26286555605956679615), + (1.11351636441160673519, 3.4270509831248422723, 3.3405490932348202056), + (-0.85065080835203998877, 0, 1.11351636441160673519), + (0.85065080835203993218, 0, -1.1135163644116066184), + (-0.6881909602355867691, -0.5, -1.1135163644116066184), + (-0.6881909602355867691, 0.5, -1.1135163644116066184), + (-0.6881909602355867691, -4.7360679774997896964, -1.1135163644116066184), + (-0.6881909602355867691, -2.1180339887498948482, -1.1135163644116066184), + (-0.6881909602355867691, 2.1180339887498948482, -1.1135163644116066184), + (-0.6881909602355867691, 4.7360679774997896964, -1.1135163644116066184), + (0.68819096023558676910, -0.5, 1.11351636441160673519), + (0.68819096023558676910, 0.5, 1.11351636441160673519), + (0.68819096023558676910, -4.7360679774997896964, 1.11351636441160673519), + (0.68819096023558676910, -2.1180339887498948482, 1.11351636441160673519), + (0.68819096023558676910, 2.1180339887498948482, 1.11351636441160673519), + (0.68819096023558676910, 4.7360679774997896964, 1.11351636441160673519), + (-0.42532540417601993887, -1.3090169943749474241, -4.7169310137059934362), + (-0.42532540417601993887, -1.3090169943749474241, 0.26286555605956679615), + (-0.42532540417601993887, 1.3090169943749474241, -4.7169310137059934362), + (-0.42532540417601993887, 1.3090169943749474241, 0.26286555605956679615), + (-0.26286555605956679615, -0.8090169943749474241, 1.11351636441160673519), + (-0.26286555605956679615, 0.8090169943749474241, 1.11351636441160673519), + (0.26286555605956679615, -0.8090169943749474241, -1.1135163644116066184), + (0.26286555605956679615, 0.8090169943749474241, -1.1135163644116066184), + (0.42532540417601996609, -1.3090169943749474241, 4.7169310137059937438), + (0.42532540417601996609, -1.3090169943749474241, -0.26286555605956679615), + (0.42532540417601996609, 1.3090169943749474241, 4.7169310137059937438), + (0.42532540417601996609, 1.3090169943749474241, -0.26286555605956679615)], + [9, 66, 47], [44, 62, 77], [20, 91, 49], [33, 47, 83], + [3, 77, 84], [12, 49, 53], [36, 84, 66], [28, 53, 62], + [73, 83, 91], [15, 84, 46], [25, 64, 43], [16, 58, 72], + [26, 46, 51], [11, 43, 74], [4, 72, 91], [60, 74, 84], + [35, 91, 64], [23, 51, 58], [19, 74, 77], [79, 83, 78], + [6, 56, 40], [76, 77, 81], [21, 78, 75], [8, 40, 58], + [31, 75, 74], [42, 58, 83], [41, 81, 56], [13, 75, 43], + [27, 51, 47], [2, 89, 71], [24, 43, 62], [17, 47, 85], + [14, 71, 56], [65, 85, 75], [22, 56, 51], [34, 62, 89], + [5, 85, 78], [32, 81, 46], [10, 53, 48], [45, 78, 64], + [7, 46, 66], [18, 48, 89], [37, 66, 85], [70, 89, 81], + [29, 64, 53], [88, 74, 1], [38, 67, 48], [42, 83, 72], + [57, 1, 85], [34, 48, 62], [59, 72, 87], [19, 62, 74], + [63, 87, 67], [17, 85, 83], [52, 75, 1], [39, 87, 49], + [22, 51, 40], [55, 1, 66], [29, 49, 64], [30, 40, 69], + [13, 64, 75], [82, 69, 87], [7, 66, 51], [90, 85, 1], + [59, 69, 72], [70, 81, 71], [88, 1, 84], [73, 72, 83], + [54, 71, 68], [5, 83, 85], [50, 68, 69], [3, 84, 81], + [57, 66, 1], [30, 68, 40], [28, 62, 48], [52, 1, 74], + [23, 40, 51], [38, 48, 86], [9, 51, 66], [80, 86, 68], + [11, 74, 62], [55, 84, 1], [54, 86, 71], [35, 64, 49], + [90, 1, 75], [41, 71, 81], [39, 49, 67], [15, 81, 84], + [61, 67, 86], [21, 75, 64], [24, 53, 43], [50, 69, 0], + [37, 85, 47], [31, 43, 75], [61, 0, 67], [27, 47, 58], + [10, 67, 53], [8, 58, 69], [90, 75, 85], [45, 91, 78], + [80, 68, 0], [36, 66, 46], [65, 78, 85], [63, 0, 87], + [32, 46, 56], [20, 87, 91], [14, 56, 68], [57, 85, 66], + [33, 58, 47], [61, 86, 0], [60, 84, 77], [37, 47, 66], + [82, 0, 69], [44, 77, 89], [16, 69, 58], [18, 89, 86], + [55, 66, 84], [26, 56, 46], [63, 67, 0], [31, 74, 43], + [36, 46, 84], [50, 0, 68], [25, 43, 53], [6, 68, 56], + [12, 53, 67], [88, 84, 74], [76, 89, 77], [82, 87, 0], + [65, 75, 78], [60, 77, 74], [80, 0, 86], [79, 78, 91], + [2, 86, 89], [4, 91, 87], [52, 74, 75], [21, 64, 78], + [18, 86, 48], [23, 58, 40], [5, 78, 83], [28, 48, 53], + [6, 40, 68], [25, 53, 64], [54, 68, 86], [33, 83, 58], + [17, 83, 47], [12, 67, 49], [41, 56, 71], [9, 47, 51], + [35, 49, 91], [2, 71, 86], [79, 91, 83], [38, 86, 67], + [26, 51, 56], [7, 51, 46], [4, 87, 72], [34, 89, 48], + [15, 46, 81], [42, 72, 58], [10, 48, 67], [27, 58, 51], + [39, 67, 87], [76, 81, 89], [3, 81, 77], [8, 69, 40], + [29, 53, 49], [19, 77, 62], [22, 40, 56], [20, 49, 87], + [32, 56, 81], [59, 87, 69], [24, 62, 53], [11, 62, 43], + [14, 68, 71], [73, 91, 72], [13, 43, 64], [70, 71, 89], + [16, 72, 69], [44, 89, 62], [30, 69, 68], [45, 64, 91]] + # Actual volume is : 51.405764746872634 + assert Abs(polytope_integrate(echidnahedron, 1) - 51.4057647468726) < 1e-12 + assert Abs(polytope_integrate(echidnahedron, expr) - 253.569603474519) <\ + 1e-12 + + # Tests for many polynomials with maximum degree given(2D case). + assert polytope_integrate(cube2, [x**2, y*z], max_degree=2) == \ + {y * z: 3125 / S(4), x ** 2: 3125 / S(3)} + + assert polytope_integrate(cube2, max_degree=2) == \ + {1: 125, x: 625 / S(2), x * z: 3125 / S(4), y: 625 / S(2), + y * z: 3125 / S(4), z ** 2: 3125 / S(3), y ** 2: 3125 / S(3), + z: 625 / S(2), x * y: 3125 / S(4), x ** 2: 3125 / S(3)} + +def test_point_sort(): + assert point_sort([Point(0, 0), Point(1, 0), Point(1, 1)]) == \ + [Point2D(1, 1), Point2D(1, 0), Point2D(0, 0)] + + fig6 = Polygon((0, 0), (1, 0), (1, 1)) + assert polytope_integrate(fig6, x*y) == Rational(-1, 8) + assert polytope_integrate(fig6, x*y, clockwise = True) == Rational(1, 8) + + +def test_polytopes_intersecting_sides(): + fig5 = Polygon(Point(-4.165, -0.832), Point(-3.668, 1.568), + Point(-3.266, 1.279), Point(-1.090, -2.080), + Point(3.313, -0.683), Point(3.033, -4.845), + Point(-4.395, 4.840), Point(-1.007, -3.328)) + assert polytope_integrate(fig5, x**2 + x*y + y**2) ==\ + S(1633405224899363)/(24*10**12) + + fig6 = Polygon(Point(-3.018, -4.473), Point(-0.103, 2.378), + Point(-1.605, -2.308), Point(4.516, -0.771), + Point(4.203, 0.478)) + assert polytope_integrate(fig6, x**2 + x*y + y**2) ==\ + S(88161333955921)/(3*10**12) + + +def test_max_degree(): + polygon = Polygon((0, 0), (0, 1), (1, 1), (1, 0)) + polys = [1, x, y, x*y, x**2*y, x*y**2] + assert polytope_integrate(polygon, polys, max_degree=3) == \ + {1: 1, x: S.Half, y: S.Half, x*y: Rational(1, 4), x**2*y: Rational(1, 6), x*y**2: Rational(1, 6)} + assert polytope_integrate(polygon, polys, max_degree=2) == \ + {1: 1, x: S.Half, y: S.Half, x*y: Rational(1, 4)} + assert polytope_integrate(polygon, polys, max_degree=1) == \ + {1: 1, x: S.Half, y: S.Half} + + +def test_main_integrate3d(): + cube = [[(0, 0, 0), (0, 0, 5), (0, 5, 0), (0, 5, 5), (5, 0, 0),\ + (5, 0, 5), (5, 5, 0), (5, 5, 5)],\ + [2, 6, 7, 3], [3, 7, 5, 1], [7, 6, 4, 5], [1, 5, 4, 0],\ + [3, 1, 0, 2], [0, 4, 6, 2]] + vertices = cube[0] + faces = cube[1:] + hp_params = hyperplane_parameters(faces, vertices) + assert main_integrate3d(1, faces, vertices, hp_params) == -125 + assert main_integrate3d(1, faces, vertices, hp_params, max_degree=1) == \ + {1: -125, y: Rational(-625, 2), z: Rational(-625, 2), x: Rational(-625, 2)} + + +def test_main_integrate(): + triangle = Polygon((0, 3), (5, 3), (1, 1)) + facets = triangle.sides + hp_params = hyperplane_parameters(triangle) + assert main_integrate(x**2 + y**2, facets, hp_params) == Rational(325, 6) + assert main_integrate(x**2 + y**2, facets, hp_params, max_degree=1) == \ + {0: 0, 1: 5, y: Rational(35, 3), x: 10} + + +def test_polygon_integrate(): + cube = [[(0, 0, 0), (0, 0, 5), (0, 5, 0), (0, 5, 5), (5, 0, 0),\ + (5, 0, 5), (5, 5, 0), (5, 5, 5)],\ + [2, 6, 7, 3], [3, 7, 5, 1], [7, 6, 4, 5], [1, 5, 4, 0],\ + [3, 1, 0, 2], [0, 4, 6, 2]] + facet = cube[1] + facets = cube[1:] + vertices = cube[0] + assert polygon_integrate(facet, [(0, 1, 0), 5], 0, facets, vertices, 1, 0) == -25 + + +def test_distance_to_side(): + point = (0, 0, 0) + assert distance_to_side(point, [(0, 0, 1), (0, 1, 0)], (1, 0, 0)) == -sqrt(2)/2 + + +def test_lineseg_integrate(): + polygon = [(0, 5, 0), (5, 5, 0), (5, 5, 5), (0, 5, 5)] + line_seg = [(0, 5, 0), (5, 5, 0)] + assert lineseg_integrate(polygon, 0, line_seg, 1, 0) == 5 + assert lineseg_integrate(polygon, 0, line_seg, 0, 0) == 0 + + +def test_integration_reduction(): + triangle = Polygon(Point(0, 3), Point(5, 3), Point(1, 1)) + facets = triangle.sides + a, b = hyperplane_parameters(triangle)[0] + assert integration_reduction(facets, 0, a, b, 1, (x, y), 0) == 5 + assert integration_reduction(facets, 0, a, b, 0, (x, y), 0) == 0 + + +def test_integration_reduction_dynamic(): + triangle = Polygon(Point(0, 3), Point(5, 3), Point(1, 1)) + facets = triangle.sides + a, b = hyperplane_parameters(triangle)[0] + x0 = facets[0].points[0] + monomial_values = [[0, 0, 0, 0], [1, 0, 0, 5],\ + [y, 0, 1, 15], [x, 1, 0, None]] + + assert integration_reduction_dynamic(facets, 0, a, b, x, 1, (x, y), 1,\ + 0, 1, x0, monomial_values, 3) == Rational(25, 2) + assert integration_reduction_dynamic(facets, 0, a, b, 0, 1, (x, y), 1,\ + 0, 1, x0, monomial_values, 3) == 0 + + +def test_is_vertex(): + assert is_vertex(2) is False + assert is_vertex((2, 3)) is True + assert is_vertex(Point(2, 3)) is True + assert is_vertex((2, 3, 4)) is True + assert is_vertex((2, 3, 4, 5)) is False + + +def test_issue_19234(): + polygon = Polygon(Point(0, 0), Point(0, 1), Point(1, 1), Point(1, 0)) + polys = [ 1, x, y, x*y, x**2*y, x*y**2] + assert polytope_integrate(polygon, polys) == \ + {1: 1, x: S.Half, y: S.Half, x*y: Rational(1, 4), x**2*y: Rational(1, 6), x*y**2: Rational(1, 6)} + polys = [ 1, x, y, x*y, 3 + x**2*y, x + x*y**2] + assert polytope_integrate(polygon, polys) == \ + {1: 1, x: S.Half, y: S.Half, x*y: Rational(1, 4), x**2*y + 3: Rational(19, 6), x*y**2 + x: Rational(2, 3)} diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_laplace.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_laplace.py new file mode 100644 index 0000000000000000000000000000000000000000..cb7222d01e3dcb3e14e8d0564610ab553e637155 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_laplace.py @@ -0,0 +1,774 @@ +from sympy.integrals.laplace import ( + laplace_transform, inverse_laplace_transform, + LaplaceTransform, InverseLaplaceTransform, + _laplace_deep_collect, laplace_correspondence, + laplace_initial_conds) +from sympy.core.function import Function, expand_mul +from sympy.core import EulerGamma, Subs, Derivative, diff +from sympy.core.exprtools import factor_terms +from sympy.core.numbers import I, oo, pi +from sympy.core.relational import Eq +from sympy.core.singleton import S +from sympy.core.symbol import Symbol, symbols +from sympy.simplify.simplify import simplify +from sympy.functions.elementary.complexes import Abs, re +from sympy.functions.elementary.exponential import exp, log, exp_polar +from sympy.functions.elementary.hyperbolic import cosh, sinh, coth, asinh +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import atan, cos, sin +from sympy.logic.boolalg import And +from sympy.functions.special.gamma_functions import ( + lowergamma, gamma, uppergamma) +from sympy.functions.special.delta_functions import DiracDelta, Heaviside +from sympy.functions.special.singularity_functions import SingularityFunction +from sympy.functions.special.zeta_functions import lerchphi +from sympy.functions.special.error_functions import ( + fresnelc, fresnels, erf, erfc, Ei, Ci, expint, E1) +from sympy.functions.special.bessel import besseli, besselj, besselk, bessely +from sympy.testing.pytest import slow, warns_deprecated_sympy +from sympy.matrices import Matrix, eye +from sympy.abc import s + + +@slow +def test_laplace_transform(): + LT = laplace_transform + ILT = inverse_laplace_transform + a, b, c = symbols('a, b, c', positive=True) + np = symbols('np', integer=True, positive=True) + t, w, x = symbols('t, w, x') + f = Function('f') + F = Function('F') + g = Function('g') + y = Function('y') + Y = Function('Y') + + # Test helper functions + assert ( + _laplace_deep_collect(exp((t+a)*(t+b)) + + besselj(2, exp((t+a)*(t+b)-t**2)), t) == + exp(a*b + t**2 + t*(a + b)) + besselj(2, exp(a*b + t*(a + b)))) + L = laplace_transform(diff(y(t), t, 3), t, s, noconds=True) + L = laplace_correspondence(L, {y: Y}) + L = laplace_initial_conds(L, t, {y: [2, 4, 8, 16, 32]}) + assert L == s**3*Y(s) - 2*s**2 - 4*s - 8 + # Test whether `noconds=True` in `doit`: + assert (2*LaplaceTransform(exp(t), t, s) - 1).doit() == -1 + 2/(s - 1) + assert (LT(a*t+t**2+t**(S(5)/2), t, s) == + (a/s**2 + 2/s**3 + 15*sqrt(pi)/(8*s**(S(7)/2)), 0, True)) + assert LT(b/(t+a), t, s) == (-b*exp(-a*s)*Ei(-a*s), 0, True) + assert (LT(1/sqrt(t+a), t, s) == + (sqrt(pi)*sqrt(1/s)*exp(a*s)*erfc(sqrt(a)*sqrt(s)), 0, True)) + assert (LT(sqrt(t)/(t+a), t, s) == + (-pi*sqrt(a)*exp(a*s)*erfc(sqrt(a)*sqrt(s)) + sqrt(pi)*sqrt(1/s), + 0, True)) + assert (LT((t+a)**(-S(3)/2), t, s) == + (-2*sqrt(pi)*sqrt(s)*exp(a*s)*erfc(sqrt(a)*sqrt(s)) + 2/sqrt(a), + 0, True)) + assert (LT(t**(S(1)/2)*(t+a)**(-1), t, s) == + (-pi*sqrt(a)*exp(a*s)*erfc(sqrt(a)*sqrt(s)) + sqrt(pi)*sqrt(1/s), + 0, True)) + assert (LT(1/(a*sqrt(t) + t**(3/2)), t, s) == + (pi*sqrt(a)*exp(a*s)*erfc(sqrt(a)*sqrt(s)), 0, True)) + assert (LT((t+a)**b, t, s) == + (s**(-b - 1)*exp(-a*s)*uppergamma(b + 1, a*s), 0, True)) + assert LT(t**5/(t+a), t, s) == (120*a**5*uppergamma(-5, a*s), 0, True) + assert LT(exp(t), t, s) == (1/(s - 1), 1, True) + assert LT(exp(2*t), t, s) == (1/(s - 2), 2, True) + assert LT(exp(a*t), t, s) == (1/(s - a), a, True) + assert LT(exp(a*(t-b)), t, s) == (exp(-a*b)/(-a + s), a, True) + assert LT(t*exp(-a*(t)), t, s) == ((a + s)**(-2), -a, True) + assert LT(t*exp(-a*(t-b)), t, s) == (exp(a*b)/(a + s)**2, -a, True) + assert LT(b*t*exp(-a*t), t, s) == (b/(a + s)**2, -a, True) + assert LT(exp(-a*exp(-t)), t, s) == (lowergamma(s, a)/a**s, 0, True) + assert LT(exp(-a*exp(t)), t, s) == (a**s*uppergamma(-s, a), 0, True) + assert (LT(t**(S(7)/4)*exp(-8*t)/gamma(S(11)/4), t, s) == + ((s + 8)**(-S(11)/4), -8, True)) + assert (LT(t**(S(3)/2)*exp(-8*t), t, s) == + (3*sqrt(pi)/(4*(s + 8)**(S(5)/2)), -8, True)) + assert LT(t**a*exp(-a*t), t, s) == ((a+s)**(-a-1)*gamma(a+1), -a, True) + assert (LT(b*exp(-a*t**2), t, s) == + (sqrt(pi)*b*exp(s**2/(4*a))*erfc(s/(2*sqrt(a)))/(2*sqrt(a)), + 0, True)) + assert (LT(exp(-2*t**2), t, s) == + (sqrt(2)*sqrt(pi)*exp(s**2/8)*erfc(sqrt(2)*s/4)/4, 0, True)) + assert (LT(b*exp(2*t**2), t, s) == + (b*LaplaceTransform(exp(2*t**2), t, s), -oo, True)) + assert (LT(t*exp(-a*t**2), t, s) == + (1/(2*a) - s*erfc(s/(2*sqrt(a)))/(4*sqrt(pi)*a**(S(3)/2)), + 0, True)) + assert (LT(exp(-a/t), t, s) == + (2*sqrt(a)*sqrt(1/s)*besselk(1, 2*sqrt(a)*sqrt(s)), 0, True)) + assert LT(sqrt(t)*exp(-a/t), t, s, simplify=True) == ( + sqrt(pi)*(sqrt(a)*sqrt(s) + 1/S(2))*sqrt(s**(-3)) * + exp(-2*sqrt(a)*sqrt(s)), 0, True) + assert (LT(exp(-a/t)/sqrt(t), t, s) == + (sqrt(pi)*sqrt(1/s)*exp(-2*sqrt(a)*sqrt(s)), 0, True)) + assert (LT(exp(-a/t)/(t*sqrt(t)), t, s) == + (sqrt(pi)*sqrt(1/a)*exp(-2*sqrt(a)*sqrt(s)), 0, True)) + # TODO: rules with sqrt(a*t) and sqrt(a/t) have stopped working after + # changes to as_base_exp + # assert ( + # LT(exp(-2*sqrt(a*t)), t, s) == + # (1/s - sqrt(pi)*sqrt(a) * exp(a/s)*erfc(sqrt(a)*sqrt(1/s)) / + # s**(S(3)/2), 0, True)) + # assert LT(exp(-2*sqrt(a*t))/sqrt(t), t, s) == ( + # exp(a/s)*erfc(sqrt(a) * sqrt(1/s))*(sqrt(pi)*sqrt(1/s)), 0, True) + assert (LT(t**4*exp(-2/t), t, s) == + (8*sqrt(2)*(1/s)**(S(5)/2)*besselk(5, 2*sqrt(2)*sqrt(s)), + 0, True)) + assert LT(sinh(a*t), t, s) == (a/(-a**2 + s**2), a, True) + assert (LT(b*sinh(a*t)**2, t, s) == + (2*a**2*b/(-4*a**2*s + s**3), 2*a, True)) + assert (LT(b*sinh(a*t)**2, t, s, simplify=True) == + (2*a**2*b/(s*(-4*a**2 + s**2)), 2*a, True)) + # The following line confirms that issue #21202 is solved + assert LT(cosh(2*t), t, s) == (s/(-4 + s**2), 2, True) + assert LT(cosh(a*t), t, s) == (s/(-a**2 + s**2), a, True) + assert (LT(cosh(a*t)**2, t, s, simplify=True) == + ((2*a**2 - s**2)/(s*(4*a**2 - s**2)), 2*a, True)) + assert (LT(sinh(x+3), x, s, simplify=True) == + ((s*sinh(3) + cosh(3))/(s**2 - 1), 1, True)) + L, _, _ = LT(42*sin(w*t+x)**2, t, s) + assert ( + L - + 21*(s**2 + s*(-s*cos(2*x) + 2*w*sin(2*x)) + + 4*w**2)/(s*(s**2 + 4*w**2))).simplify() == 0 + # The following line replaces the old test test_issue_7173() + assert LT(sinh(a*t)*cosh(a*t), t, s, simplify=True) == (a/(-4*a**2 + s**2), + 2*a, True) + assert LT(sinh(a*t)/t, t, s) == (log((a + s)/(-a + s))/2, a, True) + assert (LT(t**(-S(3)/2)*sinh(a*t), t, s) == + (-sqrt(pi)*(sqrt(-a + s) - sqrt(a + s)), a, True)) + # assert (LT(sinh(2*sqrt(a*t)), t, s) == + # (sqrt(pi)*sqrt(a)*exp(a/s)/s**(S(3)/2), 0, True)) + # assert (LT(sqrt(t)*sinh(2*sqrt(a*t)), t, s, simplify=True) == + # ((-sqrt(a)*s**(S(5)/2) + sqrt(pi)*s**2*(2*a + s)*exp(a/s) * + # erf(sqrt(a)*sqrt(1/s))/2)/s**(S(9)/2), 0, True)) + # assert (LT(sinh(2*sqrt(a*t))/sqrt(t), t, s) == + # (sqrt(pi)*exp(a/s)*erf(sqrt(a)*sqrt(1/s))/sqrt(s), 0, True)) + # assert (LT(sinh(sqrt(a*t))**2/sqrt(t), t, s) == + # (sqrt(pi)*(exp(a/s) - 1)/(2*sqrt(s)), 0, True)) + assert (LT(t**(S(3)/7)*cosh(a*t), t, s) == + (((a + s)**(-S(10)/7) + (-a+s)**(-S(10)/7))*gamma(S(10)/7)/2, + a, True)) + # assert (LT(cosh(2*sqrt(a*t)), t, s) == + # (sqrt(pi)*sqrt(a)*exp(a/s)*erf(sqrt(a)*sqrt(1/s))/s**(S(3)/2) + + # 1/s, 0, True)) + # assert (LT(sqrt(t)*cosh(2*sqrt(a*t)), t, s) == + # (sqrt(pi)*(a + s/2)*exp(a/s)/s**(S(5)/2), 0, True)) + # assert (LT(cosh(2*sqrt(a*t))/sqrt(t), t, s) == + # (sqrt(pi)*exp(a/s)/sqrt(s), 0, True)) + # assert (LT(cosh(sqrt(a*t))**2/sqrt(t), t, s) == + # (sqrt(pi)*(exp(a/s) + 1)/(2*sqrt(s)), 0, True)) + assert LT(log(t), t, s, simplify=True) == ( + (-log(s) - EulerGamma)/s, 0, True) + assert (LT(-log(t/a), t, s, simplify=True) == + ((log(a) + log(s) + EulerGamma)/s, 0, True)) + assert LT(log(1+a*t), t, s) == (-exp(s/a)*Ei(-s/a)/s, 0, True) + assert (LT(log(t+a), t, s, simplify=True) == + ((s*log(a) - exp(s/a)*Ei(-s/a))/s**2, 0, True)) + assert (LT(log(t)/sqrt(t), t, s, simplify=True) == + (sqrt(pi)*(-log(s) - log(4) - EulerGamma)/sqrt(s), 0, True)) + assert (LT(t**(S(5)/2)*log(t), t, s, simplify=True) == + (sqrt(pi)*(-15*log(s) - log(1073741824) - 15*EulerGamma + 46) / + (8*s**(S(7)/2)), 0, True)) + assert (LT(t**3*log(t), t, s, noconds=True, simplify=True) - + 6*(-log(s) - S.EulerGamma + S(11)/6)/s**4).simplify() == S.Zero + assert (LT(log(t)**2, t, s, simplify=True) == + (((log(s) + EulerGamma)**2 + pi**2/6)/s, 0, True)) + assert (LT(exp(-a*t)*log(t), t, s, simplify=True) == + ((-log(a + s) - EulerGamma)/(a + s), -a, True)) + assert LT(sin(a*t), t, s) == (a/(a**2 + s**2), 0, True) + assert (LT(Abs(sin(a*t)), t, s) == + (a*coth(pi*s/(2*a))/(a**2 + s**2), 0, True)) + assert LT(sin(a*t)/t, t, s) == (atan(a/s), 0, True) + assert LT(sin(a*t)**2/t, t, s) == (log(4*a**2/s**2 + 1)/4, 0, True) + assert (LT(sin(a*t)**2/t**2, t, s) == + (a*atan(2*a/s) - s*log(4*a**2/s**2 + 1)/4, 0, True)) + # assert (LT(sin(2*sqrt(a*t)), t, s) == + # (sqrt(pi)*sqrt(a)*exp(-a/s)/s**(S(3)/2), 0, True)) + # assert LT(sin(2*sqrt(a*t))/t, t, s) == (pi*erf(sqrt(a)*sqrt(1/s)), 0, True) + assert LT(cos(a*t), t, s) == (s/(a**2 + s**2), 0, True) + assert (LT(cos(a*t)**2, t, s) == + ((2*a**2 + s**2)/(s*(4*a**2 + s**2)), 0, True)) + # assert (LT(sqrt(t)*cos(2*sqrt(a*t)), t, s, simplify=True) == + # (sqrt(pi)*(-a + s/2)*exp(-a/s)/s**(S(5)/2), 0, True)) + # assert (LT(cos(2*sqrt(a*t))/sqrt(t), t, s) == + # (sqrt(pi)*sqrt(1/s)*exp(-a/s), 0, True)) + assert (LT(sin(a*t)*sin(b*t), t, s) == + (2*a*b*s/((s**2 + (a - b)**2)*(s**2 + (a + b)**2)), 0, True)) + assert (LT(cos(a*t)*sin(b*t), t, s) == + (b*(-a**2 + b**2 + s**2)/((s**2 + (a - b)**2)*(s**2 + (a + b)**2)), + 0, True)) + assert (LT(cos(a*t)*cos(b*t), t, s) == + (s*(a**2 + b**2 + s**2)/((s**2 + (a - b)**2)*(s**2 + (a + b)**2)), + 0, True)) + assert (LT(-a*t*cos(a*t) + sin(a*t), t, s, simplify=True) == + (2*a**3/(a**4 + 2*a**2*s**2 + s**4), 0, True)) + assert LT(c*exp(-b*t)*sin(a*t), t, s) == (a * + c/(a**2 + (b + s)**2), -b, True) + assert LT(c*exp(-b*t)*cos(a*t), t, s) == (c*(b + s)/(a**2 + (b + s)**2), + -b, True) + L, plane, cond = LT(cos(x + 3), x, s, simplify=True) + assert plane == 0 + assert L - (s*cos(3) - sin(3))/(s**2 + 1) == 0 + # Error functions (laplace7.pdf) + assert LT(erf(a*t), t, s) == (exp(s**2/(4*a**2))*erfc(s/(2*a))/s, 0, True) + # assert LT(erf(sqrt(a*t)), t, s) == (sqrt(a)/(s*sqrt(a + s)), 0, True) + # assert (LT(exp(a*t)*erf(sqrt(a*t)), t, s, simplify=True) == + # (-sqrt(a)/(sqrt(s)*(a - s)), a, True)) + # assert (LT(erf(sqrt(a/t)/2), t, s, simplify=True) == + # (1/s - exp(-sqrt(a)*sqrt(s))/s, 0, True)) + # assert (LT(erfc(sqrt(a*t)), t, s, simplify=True) == + # (-sqrt(a)/(s*sqrt(a + s)) + 1/s, -a, True)) + # assert (LT(exp(a*t)*erfc(sqrt(a*t)), t, s) == + # (1/(sqrt(a)*sqrt(s) + s), 0, True)) + # assert LT(erfc(sqrt(a/t)/2), t, s) == (exp(-sqrt(a)*sqrt(s))/s, 0, True) + # Bessel functions (laplace8.pdf) + assert LT(besselj(0, a*t), t, s) == (1/sqrt(a**2 + s**2), 0, True) + assert (LT(besselj(1, a*t), t, s, simplify=True) == + (a/(a**2 + s**2 + s*sqrt(a**2 + s**2)), 0, True)) + assert (LT(besselj(2, a*t), t, s, simplify=True) == + (a**2/(sqrt(a**2 + s**2)*(s + sqrt(a**2 + s**2))**2), 0, True)) + assert (LT(t*besselj(0, a*t), t, s) == + (s/(a**2 + s**2)**(S(3)/2), 0, True)) + assert (LT(t*besselj(1, a*t), t, s) == + (a/(a**2 + s**2)**(S(3)/2), 0, True)) + assert (LT(t**2*besselj(2, a*t), t, s) == + (3*a**2/(a**2 + s**2)**(S(5)/2), 0, True)) + # assert LT(besselj(0, 2*sqrt(a*t)), t, s) == (exp(-a/s)/s, 0, True) + # assert (LT(t**(S(3)/2)*besselj(3, 2*sqrt(a*t)), t, s) == + # (a**(S(3)/2)*exp(-a/s)/s**4, 0, True)) + assert (LT(besselj(0, a*sqrt(t**2+b*t)), t, s, simplify=True) == + (exp(b*(s - sqrt(a**2 + s**2)))/sqrt(a**2 + s**2), 0, True)) + assert LT(besseli(0, a*t), t, s) == (1/sqrt(-a**2 + s**2), a, True) + assert (LT(besseli(1, a*t), t, s, simplify=True) == + (a/(-a**2 + s**2 + s*sqrt(-a**2 + s**2)), a, True)) + assert (LT(besseli(2, a*t), t, s, simplify=True) == + (a**2/(sqrt(-a**2 + s**2)*(s + sqrt(-a**2 + s**2))**2), a, True)) + assert LT(t*besseli(0, a*t), t, s) == (s/(-a**2 + s**2)**(S(3)/2), a, True) + assert LT(t*besseli(1, a*t), t, s) == (a/(-a**2 + s**2)**(S(3)/2), a, True) + assert (LT(t**2*besseli(2, a*t), t, s) == + (3*a**2/(-a**2 + s**2)**(S(5)/2), a, True)) + # assert (LT(t**(S(3)/2)*besseli(3, 2*sqrt(a*t)), t, s) == + # (a**(S(3)/2)*exp(a/s)/s**4, 0, True)) + assert (LT(bessely(0, a*t), t, s) == + (-2*asinh(s/a)/(pi*sqrt(a**2 + s**2)), 0, True)) + assert (LT(besselk(0, a*t), t, s) == + (log((s + sqrt(-a**2 + s**2))/a)/sqrt(-a**2 + s**2), -a, True)) + assert (LT(sin(a*t)**4, t, s, simplify=True) == + (24*a**4/(s*(64*a**4 + 20*a**2*s**2 + s**4)), 0, True)) + # Test general rules and unevaluated forms + # These all also test whether issue #7219 is solved. + assert LT(Heaviside(t-1)*cos(t-1), t, s) == (s*exp(-s)/(s**2 + 1), 0, True) + assert LT(a*f(t), t, w) == (a*LaplaceTransform(f(t), t, w), -oo, True) + assert (LT(a*Heaviside(t+1)*f(t+1), t, s) == + (a*LaplaceTransform(f(t + 1), t, s), -oo, True)) + assert (LT(a*Heaviside(t-1)*f(t-1), t, s) == + (a*LaplaceTransform(f(t), t, s)*exp(-s), -oo, True)) + assert (LT(b*f(t/a), t, s) == + (a*b*LaplaceTransform(f(t), t, a*s), -oo, True)) + assert LT(exp(-f(x)*t), t, s) == (1/(s + f(x)), -re(f(x)), True) + assert (LT(exp(-a*t)*f(t), t, s) == + (LaplaceTransform(f(t), t, a + s), -oo, True)) + # assert (LT(exp(-a*t)*erfc(sqrt(b/t)/2), t, s) == + # (exp(-sqrt(b)*sqrt(a + s))/(a + s), -a, True)) + assert (LT(sinh(a*t)*f(t), t, s) == + (LaplaceTransform(f(t), t, -a + s)/2 - + LaplaceTransform(f(t), t, a + s)/2, -oo, True)) + assert (LT(sinh(a*t)*t, t, s, simplify=True) == + (2*a*s/(a**4 - 2*a**2*s**2 + s**4), a, True)) + assert (LT(cosh(a*t)*f(t), t, s) == + (LaplaceTransform(f(t), t, -a + s)/2 + + LaplaceTransform(f(t), t, a + s)/2, -oo, True)) + assert (LT(cosh(a*t)*t, t, s, simplify=True) == + (1/(2*(a + s)**2) + 1/(2*(a - s)**2), a, True)) + assert (LT(sin(a*t)*f(t), t, s, simplify=True) == + (I*(-LaplaceTransform(f(t), t, -I*a + s) + + LaplaceTransform(f(t), t, I*a + s))/2, -oo, True)) + assert (LT(sin(f(t)), t, s) == + (LaplaceTransform(sin(f(t)), t, s), -oo, True)) + assert (LT(sin(a*t)*t, t, s, simplify=True) == + (2*a*s/(a**4 + 2*a**2*s**2 + s**4), 0, True)) + assert (LT(cos(a*t)*f(t), t, s) == + (LaplaceTransform(f(t), t, -I*a + s)/2 + + LaplaceTransform(f(t), t, I*a + s)/2, -oo, True)) + assert (LT(cos(a*t)*t, t, s, simplify=True) == + ((-a**2 + s**2)/(a**4 + 2*a**2*s**2 + s**4), 0, True)) + L, plane, _ = LT(sin(a*t+b)**2*f(t), t, s) + assert plane == -oo + assert ( + -L + ( + LaplaceTransform(f(t), t, s)/2 - + LaplaceTransform(f(t), t, -2*I*a + s)*exp(2*I*b)/4 - + LaplaceTransform(f(t), t, 2*I*a + s)*exp(-2*I*b)/4)) == 0 + L = LT(sin(a*t+b)**2*f(t), t, s, noconds=True) + assert ( + laplace_correspondence(L, {f: F}) == + F(s)/2 - F(-2*I*a + s)*exp(2*I*b)/4 - + F(2*I*a + s)*exp(-2*I*b)/4) + L, plane, _ = LT(sin(a*t)**3*cosh(b*t), t, s) + assert plane == b + assert ( + -L - 3*a/(8*(9*a**2 + b**2 + 2*b*s + s**2)) - + 3*a/(8*(9*a**2 + b**2 - 2*b*s + s**2)) + + 3*a/(8*(a**2 + b**2 + 2*b*s + s**2)) + + 3*a/(8*(a**2 + b**2 - 2*b*s + s**2))).simplify() == 0 + assert (LT(t**2*exp(-t**2), t, s) == + (sqrt(pi)*s**2*exp(s**2/4)*erfc(s/2)/8 - s/4 + + sqrt(pi)*exp(s**2/4)*erfc(s/2)/4, 0, True)) + assert (LT((a*t**2 + b*t + c)*f(t), t, s) == + (a*Derivative(LaplaceTransform(f(t), t, s), (s, 2)) - + b*Derivative(LaplaceTransform(f(t), t, s), s) + + c*LaplaceTransform(f(t), t, s), -oo, True)) + assert (LT(t**np*g(t), t, s) == + ((-1)**np*Derivative(LaplaceTransform(g(t), t, s), (s, np)), + -oo, True)) + # The following tests check whether _piecewise_to_heaviside works: + x1 = Piecewise((0, t <= 0), (1, t <= 1), (0, True)) + X1 = LT(x1, t, s)[0] + assert X1 == 1/s - exp(-s)/s + y1 = ILT(X1, s, t) + assert y1 == Heaviside(t) - Heaviside(t - 1) + x1 = Piecewise((0, t <= 0), (t, t <= 1), (2-t, t <= 2), (0, True)) + X1 = LT(x1, t, s)[0].simplify() + assert X1 == (exp(2*s) - 2*exp(s) + 1)*exp(-2*s)/s**2 + y1 = ILT(X1, s, t) + assert ( + -y1 + t*Heaviside(t) + (t - 2)*Heaviside(t - 2) - + 2*(t - 1)*Heaviside(t - 1)).simplify() == 0 + x1 = Piecewise((exp(t), t <= 0), (1, t <= 1), (exp(-(t)), True)) + X1 = LT(x1, t, s)[0] + assert X1 == exp(-1)*exp(-s)/(s + 1) + 1/s - exp(-s)/s + y1 = ILT(X1, s, t) + assert y1 == ( + exp(-1)*exp(1 - t)*Heaviside(t - 1) + Heaviside(t) - Heaviside(t - 1)) + x1 = Piecewise((0, x <= 0), (1, x <= 1), (0, True)) + X1 = LT(x1, t, s)[0] + assert X1 == Piecewise((0, x <= 0), (1, x <= 1), (0, True))/s + x1 = [ + a*Piecewise((1, And(t > 1, t <= 3)), (2, True)), + a*Piecewise((1, And(t >= 1, t <= 3)), (2, True)), + a*Piecewise((1, And(t >= 1, t < 3)), (2, True)), + a*Piecewise((1, And(t > 1, t < 3)), (2, True))] + for x2 in x1: + assert LT(x2, t, s)[0].expand() == 2*a/s - a*exp(-s)/s + a*exp(-3*s)/s + assert ( + LT(Piecewise((1, Eq(t, 1)), (2, True)), t, s)[0] == + LaplaceTransform(Piecewise((1, Eq(t, 1)), (2, True)), t, s)) + # The following lines test whether _laplace_transform successfully + # removes Heaviside(1) before processing espressions. It fails if + # Heaviside(t) remains because then meijerg functions will appear. + X1 = 1/sqrt(a*s**2-b) + x1 = ILT(X1, s, t) + Y1 = LT(x1, t, s)[0] + Z1 = (Y1**2/X1**2).simplify() + assert Z1 == 1 + # The following two lines test whether issues #5813 and #7176 are solved. + assert (LT(diff(f(t), (t, 1)), t, s, noconds=True) == + s*LaplaceTransform(f(t), t, s) - f(0)) + assert (LT(diff(f(t), (t, 3)), t, s, noconds=True) == + s**3*LaplaceTransform(f(t), t, s) - s**2*f(0) - + s*Subs(Derivative(f(t), t), t, 0) - + Subs(Derivative(f(t), (t, 2)), t, 0)) + # Issue #7219 + assert (LT(diff(f(x, t, w), t, 2), t, s) == + (s**2*LaplaceTransform(f(x, t, w), t, s) - s*f(x, 0, w) - + Subs(Derivative(f(x, t, w), t), t, 0), -oo, True)) + # Issue #23307 + assert (LT(10*diff(f(t), (t, 1)), t, s, noconds=True) == + 10*s*LaplaceTransform(f(t), t, s) - 10*f(0)) + assert (LT(a*f(b*t)+g(c*t), t, s, noconds=True) == + a*LaplaceTransform(f(t), t, s/b)/b + + LaplaceTransform(g(t), t, s/c)/c) + assert inverse_laplace_transform( + f(w), w, t, plane=0) == InverseLaplaceTransform(f(w), w, t, 0) + assert (LT(f(t)*g(t), t, s, noconds=True) == + LaplaceTransform(f(t)*g(t), t, s)) + # Issue #24294 + assert (LT(b*f(a*t), t, s, noconds=True) == + b*LaplaceTransform(f(t), t, s/a)/a) + assert LT(3*exp(t)*Heaviside(t), t, s) == (3/(s - 1), 1, True) + assert (LT(2*sin(t)*Heaviside(t), t, s, simplify=True) == + (2/(s**2 + 1), 0, True)) + # Issue #25293 + assert ( + LT((1/(t-1))*sin(4*pi*(t-1))*DiracDelta(t-1) * + (Heaviside(t-1/4) - Heaviside(t-2)), t, s)[0] == 4*pi*exp(-s)) + # additional basic tests from wikipedia + assert (LT((t - a)**b*exp(-c*(t - a))*Heaviside(t - a), t, s) == + ((c + s)**(-b - 1)*exp(-a*s)*gamma(b + 1), -c, True)) + assert ( + LT((exp(2*t)-1)*exp(-b-t)*Heaviside(t)/2, t, s, noconds=True, + simplify=True) == + exp(-b)/(s**2 - 1)) + # DiracDelta function: standard cases + assert LT(DiracDelta(t), t, s) == (1, -oo, True) + assert LT(DiracDelta(a*t), t, s) == (1/a, -oo, True) + assert LT(DiracDelta(t/42), t, s) == (42, -oo, True) + assert LT(DiracDelta(t+42), t, s) == (0, -oo, True) + assert (LT(DiracDelta(t)+DiracDelta(t-42), t, s) == + (1 + exp(-42*s), -oo, True)) + assert (LT(DiracDelta(t)-a*exp(-a*t), t, s, simplify=True) == + (s/(a + s), -a, True)) + assert ( + LT(exp(-t)*(DiracDelta(t)+DiracDelta(t-42)), t, s, simplify=True) == + (exp(-42*s - 42) + 1, -oo, True)) + assert LT(f(t)*DiracDelta(t-42), t, s) == (f(42)*exp(-42*s), -oo, True) + assert LT(f(t)*DiracDelta(b*t-a), t, s) == (f(a/b)*exp(-a*s/b)/b, + -oo, True) + assert LT(f(t)*DiracDelta(b*t+a), t, s) == (0, -oo, True) + # SingularityFunction + assert LT(SingularityFunction(t, a, -1), t, s)[0] == exp(-a*s) + assert LT(SingularityFunction(t, a, 1), t, s)[0] == exp(-a*s)/s**2 + assert LT(SingularityFunction(t, a, x), t, s)[0] == ( + LaplaceTransform(SingularityFunction(t, a, x), t, s)) + # Collection of cases that cannot be fully evaluated and/or would catch + # some common implementation errors + assert (LT(DiracDelta(t**2), t, s, noconds=True) == + LaplaceTransform(DiracDelta(t**2), t, s)) + assert LT(DiracDelta(t**2 - 1), t, s) == (exp(-s)/2, -oo, True) + assert LT(DiracDelta(t*(1 - t)), t, s) == (1 - exp(-s), -oo, True) + assert (LT((DiracDelta(t) + 1)*(DiracDelta(t - 1) + 1), t, s) == + (LaplaceTransform(DiracDelta(t)*DiracDelta(t - 1), t, s) + + 1 + exp(-s) + 1/s, 0, True)) + assert LT(DiracDelta(2*t-2*exp(a)), t, s) == (exp(-s*exp(a))/2, -oo, True) + assert LT(DiracDelta(-2*t+2*exp(a)), t, s) == (exp(-s*exp(a))/2, -oo, True) + # Heaviside tests + assert LT(Heaviside(t), t, s) == (1/s, 0, True) + assert LT(Heaviside(t - a), t, s) == (exp(-a*s)/s, 0, True) + assert LT(Heaviside(t-1), t, s) == (exp(-s)/s, 0, True) + assert LT(Heaviside(2*t-4), t, s) == (exp(-2*s)/s, 0, True) + assert LT(Heaviside(2*t+4), t, s) == (1/s, 0, True) + assert (LT(Heaviside(-2*t+4), t, s, simplify=True) == + (1/s - exp(-2*s)/s, 0, True)) + assert (LT(g(t)*Heaviside(t - w), t, s) == + (LaplaceTransform(g(t)*Heaviside(t - w), t, s), -oo, True)) + assert ( + LT(Heaviside(t-a)*g(t), t, s) == + (LaplaceTransform(g(a + t), t, s)*exp(-a*s), -oo, True)) + assert ( + LT(Heaviside(t+a)*g(t), t, s) == + (LaplaceTransform(g(t), t, s), -oo, True)) + assert ( + LT(Heaviside(-t+a)*g(t), t, s) == + (LaplaceTransform(g(t), t, s) - + LaplaceTransform(g(a + t), t, s)*exp(-a*s), -oo, True)) + assert ( + LT(Heaviside(-t-a)*g(t), t, s) == (0, 0, True)) + # Fresnel functions + assert (laplace_transform(fresnels(t), t, s, simplify=True) == + ((-sin(s**2/(2*pi))*fresnels(s/pi) + + sqrt(2)*sin(s**2/(2*pi) + pi/4)/2 - + cos(s**2/(2*pi))*fresnelc(s/pi))/s, 0, True)) + assert (laplace_transform(fresnelc(t), t, s, simplify=True) == + ((sin(s**2/(2*pi))*fresnelc(s/pi) - + cos(s**2/(2*pi))*fresnels(s/pi) + + sqrt(2)*cos(s**2/(2*pi) + pi/4)/2)/s, 0, True)) + # Matrix tests + Mt = Matrix([[exp(t), t*exp(-t)], [t*exp(-t), exp(t)]]) + Ms = Matrix([[1/(s - 1), (s + 1)**(-2)], + [(s + 1)**(-2), 1/(s - 1)]]) + # The default behaviour for Laplace transform of a Matrix returns a Matrix + # of Tuples and is deprecated: + with warns_deprecated_sympy(): + Ms_conds = Matrix( + [[(1/(s - 1), 1, True), ((s + 1)**(-2), -1, True)], + [((s + 1)**(-2), -1, True), (1/(s - 1), 1, True)]]) + with warns_deprecated_sympy(): + assert LT(Mt, t, s) == Ms_conds + # The new behavior is to return a tuple of a Matrix and the convergence + # conditions for the matrix as a whole: + assert LT(Mt, t, s, legacy_matrix=False) == (Ms, 1, True) + # With noconds=True the transformed matrix is returned without conditions + # either way: + assert LT(Mt, t, s, noconds=True) == Ms + assert LT(Mt, t, s, legacy_matrix=False, noconds=True) == Ms + + +@slow +def test_inverse_laplace_transform(): + s = symbols('s') + k, n, t = symbols('k, n, t', real=True) + a, b, c, d = symbols('a, b, c, d', positive=True) + f = Function('f') + F = Function('F') + + def ILT(g): + return inverse_laplace_transform(g, s, t) + + def ILTS(g): + return inverse_laplace_transform(g, s, t, simplify=True) + + def ILTF(g): + return laplace_correspondence( + inverse_laplace_transform(g, s, t), {f: F}) + + # Tests for the rules in Bateman54. + + # Section 4.1: Some of the Laplace transform rules can also be used well + # in the inverse transform. + assert ILTF(exp(-a*s)*F(s)) == f(-a + t) + assert ILTF(k*F(s-a)) == k*f(t)*exp(-a*t) + assert ILTF(diff(F(s), s, 3)) == -t**3*f(t) + assert ILTF(diff(F(s), s, 4)) == t**4*f(t) + + # Section 5.1: Most rules are impractical for a computer algebra system. + + # Section 5.2: Rational functions + assert ILT(2) == 2*DiracDelta(t) + assert ILT(1/s) == Heaviside(t) + assert ILT(1/s**2) == t*Heaviside(t) + assert ILT(1/s**5) == t**4*Heaviside(t)/24 + assert ILT(1/s**n) == t**(n - 1)*Heaviside(t)/gamma(n) + assert ILT(a/(a + s)) == a*exp(-a*t)*Heaviside(t) + assert ILT(s/(a + s)) == -a*exp(-a*t)*Heaviside(t) + DiracDelta(t) + assert (ILT(b*s/(s+a)**2) == + b*(-a*t*exp(-a*t)*Heaviside(t) + exp(-a*t)*Heaviside(t))) + assert (ILTS(c/((s+a)*(s+b))) == + c*(exp(a*t) - exp(b*t))*exp(-t*(a + b))*Heaviside(t)/(a - b)) + assert (ILTS(c*s/((s+a)*(s+b))) == + c*(a*exp(b*t) - b*exp(a*t))*exp(-t*(a + b))*Heaviside(t)/(a - b)) + assert ILTS(s/(a + s)**3) == t*(-a*t + 2)*exp(-a*t)*Heaviside(t)/2 + assert ILTS(1/(s*(a + s)**3)) == ( + -a**2*t**2 - 2*a*t + 2*exp(a*t) - 2)*exp(-a*t)*Heaviside(t)/(2*a**3) + assert ILT(1/(s*(a + s)**n)) == ( + Heaviside(t)*lowergamma(n, a*t)/(a**n*gamma(n))) + assert ILT((s-a)**(-b)) == t**(b - 1)*exp(a*t)*Heaviside(t)/gamma(b) + assert ILT((a + s)**(-2)) == t*exp(-a*t)*Heaviside(t) + assert ILT((a + s)**(-5)) == t**4*exp(-a*t)*Heaviside(t)/24 + assert ILT(s**2/(s**2 + 1)) == -sin(t)*Heaviside(t) + DiracDelta(t) + assert ILT(1 - 1/(s**2 + 1)) == -sin(t)*Heaviside(t) + DiracDelta(t) + assert ILT(a/(a**2 + s**2)) == sin(a*t)*Heaviside(t) + assert ILT(s/(s**2 + a**2)) == cos(a*t)*Heaviside(t) + assert ILT(b/(b**2 + (a + s)**2)) == exp(-a*t)*sin(b*t)*Heaviside(t) + assert (ILT(b*s/(b**2 + (a + s)**2)) == + b*(-a*exp(-a*t)*sin(b*t)/b + exp(-a*t)*cos(b*t))*Heaviside(t)) + assert ILT(1/(s**2*(s**2 + 1))) == t*Heaviside(t) - sin(t)*Heaviside(t) + assert (ILTS(c*s/(d**2*(s+a)**2+b**2)) == + c*(-a*d*sin(b*t/d) + b*cos(b*t/d))*exp(-a*t)*Heaviside(t)/(b*d**2)) + assert ILTS((b*s**2 + d)/(a**2 + s**2)**2) == ( + 2*a**2*b*sin(a*t) + (a**2*b - d)*(a*t*cos(a*t) - + sin(a*t)))*Heaviside(t)/(2*a**3) + assert ILTS(b/(s**2-a**2)) == b*sinh(a*t)*Heaviside(t)/a + assert (ILT(b/(s**2-a**2)) == + b*(exp(a*t)*Heaviside(t)/(2*a) - exp(-a*t)*Heaviside(t)/(2*a))) + assert ILTS(b*s/(s**2-a**2)) == b*cosh(a*t)*Heaviside(t) + assert (ILT(b/(s*(s+a))) == + b*(Heaviside(t)/a - exp(-a*t)*Heaviside(t)/a)) + # Issue #24424 + assert (ILTS((s + 8)/((s + 2)*(s**2 + 2*s + 10))) == + ((8*sin(3*t) - 9*cos(3*t))*exp(t) + 9)*exp(-2*t)*Heaviside(t)/15) + # Issue #8514; this is not important anymore, since this function + # is not solved by integration anymore + assert (ILT(1/(a*s**2+b*s+c)) == + 2*exp(-b*t/(2*a))*sin(t*sqrt(4*a*c - b**2)/(2*a)) * + Heaviside(t)/sqrt(4*a*c - b**2)) + + # Section 5.3: Irrational algebraic functions + assert ( # (1) + ILT(1/sqrt(s)/(b*s-a)) == + exp(a*t/b)*Heaviside(t)*erf(sqrt(a)*sqrt(t)/sqrt(b))/(sqrt(a)*sqrt(b))) + assert ( # (2) + ILT(1/sqrt(k*s)/(c*s-a)/s) == + (-2*c*sqrt(t)/(sqrt(pi)*a) + + c**(S(3)/2)*exp(a*t/c)*erf(sqrt(a)*sqrt(t)/sqrt(c))/a**(S(3)/2)) * + Heaviside(t)/(c*sqrt(k))) + assert ( # (4) + ILT(1/(sqrt(c*s)+a)) == (-a*exp(a**2*t/c)*erfc(a*sqrt(t)/sqrt(c))/c + + 1/(sqrt(pi)*sqrt(c)*sqrt(t)))*Heaviside(t)) + assert ( # (5) + ILT(a/s/(b*sqrt(s)+a)) == + (-exp(a**2*t/b**2)*erfc(a*sqrt(t)/b) + 1)*Heaviside(t)) + assert ( # (6) + ILT((a-b)*sqrt(s)/(sqrt(s)+sqrt(a))/(s-b)) == + (sqrt(a)*sqrt(b)*exp(b*t)*erfc(sqrt(b)*sqrt(t)) + + a*exp(a*t)*erfc(sqrt(a)*sqrt(t)) - b*exp(b*t))*Heaviside(t)) + assert ( # (7) + ILT(1/sqrt(s)/(sqrt(b*s)+a)) == + exp(a**2*t/b)*Heaviside(t)*erfc(a*sqrt(t)/sqrt(b))/sqrt(b)) + assert ( # (8) + ILT(a**2/(sqrt(s)+a)/s**(S(3)/2)) == + (2*a*sqrt(t)/sqrt(pi) + exp(a**2*t)*erfc(a*sqrt(t)) - 1) * + Heaviside(t)) + assert ( # (9) + ILT((a-b)*sqrt(b)/(s-b)/sqrt(s)/(sqrt(s)+sqrt(a))) == + (sqrt(a)*exp(b*t)*erf(sqrt(b)*sqrt(t)) + + sqrt(b)*exp(a*t)*erfc(sqrt(a)*sqrt(t)) - + sqrt(b)*exp(b*t))*Heaviside(t)) + assert ( # (10) + ILT(1/(sqrt(s)+sqrt(a))**2) == + (-2*sqrt(a)*sqrt(t)/sqrt(pi) + + (-2*a*t + 1)*(erf(sqrt(a)*sqrt(t)) - + 1)*exp(a*t) + 1)*Heaviside(t)) + assert ( # (11) + ILT(1/(sqrt(s)+sqrt(a))**2/s) == + ((2*t - 1/a)*exp(a*t)*erfc(sqrt(a)*sqrt(t)) + 1/a - + 2*sqrt(t)/(sqrt(pi)*sqrt(a)))*Heaviside(t)) + assert ( # (12) + ILT(1/(sqrt(s)+a)**2/sqrt(s)) == + (-2*a*t*exp(a**2*t)*erfc(a*sqrt(t)) + + 2*sqrt(t)/sqrt(pi))*Heaviside(t)) + assert ( # (13) + ILT(1/(sqrt(s)+a)**3) == + (-a*t*(2*a**2*t + 3)*exp(a**2*t)*erfc(a*sqrt(t)) + + 2*sqrt(t)*(a**2*t + 1)/sqrt(pi))*Heaviside(t)) + x = ( + - ILT(sqrt(s)/(sqrt(s)+a)**3) + + 2*(sqrt(pi)*a**2*t*(-2*sqrt(pi)*erfc(a*sqrt(t)) + + 2*exp(-a**2*t)/(a*sqrt(t))) * + (-a**4*t**2 - 5*a**2*t/2 - S.Half) * exp(a**2*t)/2 + + sqrt(pi)*a*sqrt(t)*(a**2*t + 1)/2) * + Heaviside(t)/(pi*a**2*t)).simplify() + assert ( # (14) + x == 0) + x = ( + - ILT(1/sqrt(s)/(sqrt(s)+a)**3) + + Heaviside(t)*(sqrt(t)*((2*a**2*t + 1) * + (sqrt(pi)*a*sqrt(t)*exp(a**2*t) * + erfc(a*sqrt(t)) - 1) + 1) / + (sqrt(pi)*a))).simplify() + assert ( # (15) + x == 0) + assert ( # (16) + factor_terms(ILT(3/(sqrt(s)+a)**4)) == + 3*(-2*a**3*t**(S(5)/2)*(2*a**2*t + 5)/(3*sqrt(pi)) + + t*(4*a**4*t**2 + 12*a**2*t + 3)*exp(a**2*t) * + erfc(a*sqrt(t))/3)*Heaviside(t)) + assert ( # (17) + ILT((sqrt(s)-a)/(s*(sqrt(s)+a))) == + (2*exp(a**2*t)*erfc(a*sqrt(t))-1)*Heaviside(t)) + assert ( # (18) + ILT((sqrt(s)-a)**2/(s*(sqrt(s)+a)**2)) == ( + 1 + 8*a**2*t*exp(a**2*t)*erfc(a*sqrt(t)) - + 8/sqrt(pi)*a*sqrt(t))*Heaviside(t)) + assert ( # (19) + ILT((sqrt(s)-a)**3/(s*(sqrt(s)+a)**3)) == Heaviside(t)*( + 2*(8*a**4*t**2+8*a**2*t+1)*exp(a**2*t) * + erfc(a*sqrt(t))-8/sqrt(pi)*a*sqrt(t)*(2*a**2*t+1)-1)) + assert ( # (22) + ILT(sqrt(s+a)/(s+b)) == Heaviside(t)*( + exp(-a*t)/sqrt(t)/sqrt(pi) + + sqrt(a-b)*exp(-b*t)*erf(sqrt(a-b)*sqrt(t)))) + assert ( # (23) + ILT(1/sqrt(s+b)/(s+a)) == Heaviside(t)*( + 1/sqrt(b-a)*exp(-a*t)*erf(sqrt(b-a)*sqrt(t)))) + assert ( # (35) + ILT(1/sqrt(s**2+a**2)) == Heaviside(t)*( + besselj(0, a*t))) + assert ( # (44) + ILT(1/sqrt(s**2-a**2)) == Heaviside(t)*( + besseli(0, a*t))) + + # Miscellaneous tests + # Can _inverse_laplace_time_shift deal with positive exponents? + assert ( + - ILT((s**2*exp(2*s) + 4*exp(s) - 4)*exp(-2*s)/(s*(s**2 + 1))) + + cos(t)*Heaviside(t) + 4*cos(t - 2)*Heaviside(t - 2) - + 4*cos(t - 1)*Heaviside(t - 1) - 4*Heaviside(t - 2) + + 4*Heaviside(t - 1)).simplify() == 0 + + +@slow +def test_inverse_laplace_transform_old(): + from sympy.functions.special.delta_functions import DiracDelta + ILT = inverse_laplace_transform + a, b, c, d = symbols('a b c d', positive=True) + n, r = symbols('n, r', real=True) + t, z = symbols('t z') + f = Function('f') + F = Function('F') + + def simp_hyp(expr): + return factor_terms(expand_mul(expr)).rewrite(sin) + + L = ILT(F(s), s, t) + assert laplace_correspondence(L, {f: F}) == f(t) + assert ILT(exp(-a*s)/s, s, t) == Heaviside(-a + t) + assert ILT(exp(-a*s)/(b + s), s, t) == exp(-b*(-a + t))*Heaviside(-a + t) + assert (ILT((b + s)/(a**2 + (b + s)**2), s, t) == + exp(-b*t)*cos(a*t)*Heaviside(t)) + assert (ILT(exp(-a*s)/s**b, s, t) == + (-a + t)**(b - 1)*Heaviside(-a + t)/gamma(b)) + assert (ILT(exp(-a*s)/sqrt(s**2 + 1), s, t) == + Heaviside(-a + t)*besselj(0, a - t)) + assert ILT(1/(s*sqrt(s + 1)), s, t) == Heaviside(t)*erf(sqrt(t)) + # TODO sinh/cosh shifted come out a mess. also delayed trig is a mess + # TODO should this simplify further? + assert (ILT(exp(-a*s)/s**b, s, t) == + (t - a)**(b - 1)*Heaviside(t - a)/gamma(b)) + assert (ILT(exp(-a*s)/sqrt(1 + s**2), s, t) == + Heaviside(t - a)*besselj(0, a - t)) # note: besselj(0, x) is even + # XXX ILT turns these branch factor into trig functions ... + assert ( + simplify(ILT(a**b*(s + sqrt(s**2 - a**2))**(-b)/sqrt(s**2 - a**2), + s, t).rewrite(exp)) == + Heaviside(t)*besseli(b, a*t)) + assert ( + ILT(a**b*(s + sqrt(s**2 + a**2))**(-b)/sqrt(s**2 + a**2), + s, t, simplify=True).rewrite(exp) == + Heaviside(t)*besselj(b, a*t)) + assert ILT(1/(s*sqrt(s + 1)), s, t) == Heaviside(t)*erf(sqrt(t)) + # TODO can we make erf(t) work? + assert (ILT((s * eye(2) - Matrix([[1, 0], [0, 2]])).inv(), s, t) == + Matrix([[exp(t)*Heaviside(t), 0], [0, exp(2*t)*Heaviside(t)]])) + # Test time_diff rule + assert (ILT(s**42*f(s), s, t) == + Derivative(InverseLaplaceTransform(f(s), s, t, None), (t, 42))) + assert ILT(cos(s), s, t) == InverseLaplaceTransform(cos(s), s, t, None) + # Rules for testing different DiracDelta cases + assert ( + ILT(1 + 2*s + 3*s**2 + 5*s**3, s, t) == DiracDelta(t) + + 2*DiracDelta(t, 1) + 3*DiracDelta(t, 2) + 5*DiracDelta(t, 3)) + assert (ILT(2*exp(3*s) - 5*exp(-7*s), s, t) == + 2*InverseLaplaceTransform(exp(3*s), s, t, None) - + 5*DiracDelta(t - 7)) + a = cos(sin(7)/2) + assert ILT(a*exp(-3*s), s, t) == a*DiracDelta(t - 3) + assert ILT(exp(2*s), s, t) == InverseLaplaceTransform(exp(2*s), s, t, None) + r = Symbol('r', real=True) + assert ILT(exp(r*s), s, t) == InverseLaplaceTransform(exp(r*s), s, t, None) + # Rules for testing whether Heaviside(t) is treated properly in diff rule + assert ILT(s**2/(a**2 + s**2), s, t) == ( + -a*sin(a*t)*Heaviside(t) + DiracDelta(t)) + assert ILT(s**2*(f(s) + 1/(a**2 + s**2)), s, t) == ( + -a*sin(a*t)*Heaviside(t) + DiracDelta(t) + + Derivative(InverseLaplaceTransform(f(s), s, t, None), (t, 2))) + # Rules from the previous test_inverse_laplace_transform_delta_cond(): + assert (ILT(exp(r*s), s, t, noconds=False) == + (InverseLaplaceTransform(exp(r*s), s, t, None), True)) + # inversion does not exist: verify it doesn't evaluate to DiracDelta + for z in (Symbol('z', extended_real=False), + Symbol('z', imaginary=True, zero=False)): + f = ILT(exp(z*s), s, t, noconds=False) + f = f[0] if isinstance(f, tuple) else f + assert f.func != DiracDelta + + +@slow +def test_expint(): + x = Symbol('x') + a = Symbol('a') + u = Symbol('u', polar=True) + + # TODO LT of Si, Shi, Chi is a mess ... + assert laplace_transform(Ci(x), x, s) == (-log(1 + s**2)/2/s, 0, True) + assert (laplace_transform(expint(a, x), x, s, simplify=True) == + (lerchphi(s*exp_polar(I*pi), 1, a), 0, re(a) > S.Zero)) + assert (laplace_transform(expint(1, x), x, s, simplify=True) == + (log(s + 1)/s, 0, True)) + assert (laplace_transform(expint(2, x), x, s, simplify=True) == + ((s - log(s + 1))/s**2, 0, True)) + assert (inverse_laplace_transform(-log(1 + s**2)/2/s, s, u).expand() == + Heaviside(u)*Ci(u)) + assert ( + inverse_laplace_transform(log(s + 1)/s, s, x, + simplify=True).rewrite(expint) == + Heaviside(x)*E1(x)) + assert ( + inverse_laplace_transform( + (s - log(s + 1))/s**2, s, x, + simplify=True).rewrite(expint).expand() == + (expint(2, x)*Heaviside(x)).rewrite(Ei).rewrite(expint).expand()) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_lineintegrals.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_lineintegrals.py new file mode 100644 index 0000000000000000000000000000000000000000..d0af146b52406a153d033286f3fcfa79334d2a73 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_lineintegrals.py @@ -0,0 +1,13 @@ +from sympy.core.numbers import E +from sympy.core.symbol import symbols +from sympy.functions.elementary.exponential import log +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.geometry.curve import Curve +from sympy.integrals.integrals import line_integrate + +s, t, x, y, z = symbols('s,t,x,y,z') + + +def test_lineintegral(): + c = Curve([E**t + 1, E**t - 1], (t, 0, log(2))) + assert line_integrate(x + y, c, [x, y]) == 3*sqrt(2) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_manual.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_manual.py new file mode 100644 index 0000000000000000000000000000000000000000..74cae4521ec97608a21553e0203be60c210387b3 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_manual.py @@ -0,0 +1,714 @@ +from sympy.core.expr import Expr +from sympy.core.mul import Mul +from sympy.core.function import (Derivative, Function, diff, expand) +from sympy.core.numbers import (I, Rational, pi) +from sympy.core.relational import Ne +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, Symbol, symbols) +from sympy.functions.elementary.exponential import (exp, log) +from sympy.functions.elementary.hyperbolic import (asinh, csch, cosh, coth, sech, sinh, tanh) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise, piecewise_fold +from sympy.functions.elementary.trigonometric import (acos, acot, acsc, asec, asin, atan, cos, cot, csc, sec, sin, tan) +from sympy.functions.special.delta_functions import Heaviside, DiracDelta +from sympy.functions.special.elliptic_integrals import (elliptic_e, elliptic_f) +from sympy.functions.special.error_functions import (Chi, Ci, Ei, Shi, Si, erf, erfi, fresnelc, fresnels, li) +from sympy.functions.special.gamma_functions import uppergamma +from sympy.functions.special.polynomials import (assoc_laguerre, chebyshevt, chebyshevu, gegenbauer, hermite, jacobi, laguerre, legendre) +from sympy.functions.special.zeta_functions import polylog +from sympy.integrals.integrals import (Integral, integrate) +from sympy.logic.boolalg import And +from sympy.integrals.manualintegrate import (manualintegrate, find_substitutions, + _parts_rule, integral_steps, manual_subs) +from sympy.testing.pytest import raises, slow + +x, y, z, u, n, a, b, c, d, e = symbols('x y z u n a b c d e') +f = Function('f') + + +def assert_is_integral_of(f: Expr, F: Expr): + assert manualintegrate(f, x) == F + assert F.diff(x).equals(f) + + +def test_find_substitutions(): + assert find_substitutions((cot(x)**2 + 1)**2*csc(x)**2*cot(x)**2, x, u) == \ + [(cot(x), 1, -u**6 - 2*u**4 - u**2)] + assert find_substitutions((sec(x)**2 + tan(x) * sec(x)) / (sec(x) + tan(x)), + x, u) == [(sec(x) + tan(x), 1, 1/u)] + assert (-x**2, Rational(-1, 2), exp(u)) in find_substitutions(x * exp(-x**2), x, u) + assert not find_substitutions(Derivative(f(x), x)**2, x, u) + + +def test_manualintegrate_polynomials(): + assert manualintegrate(y, x) == x*y + assert manualintegrate(exp(2), x) == x * exp(2) + assert manualintegrate(x**2, x) == x**3 / 3 + assert manualintegrate(3 * x**2 + 4 * x**3, x) == x**3 + x**4 + + assert manualintegrate((x + 2)**3, x) == (x + 2)**4 / 4 + assert manualintegrate((3*x + 4)**2, x) == (3*x + 4)**3 / 9 + + assert manualintegrate((u + 2)**3, u) == (u + 2)**4 / 4 + assert manualintegrate((3*u + 4)**2, u) == (3*u + 4)**3 / 9 + + +def test_manualintegrate_exponentials(): + assert manualintegrate(exp(2*x), x) == exp(2*x) / 2 + assert manualintegrate(2**x, x) == (2 ** x) / log(2) + assert_is_integral_of(1/sqrt(1-exp(2*x)), + log(sqrt(1 - exp(2*x)) - 1)/2 - log(sqrt(1 - exp(2*x)) + 1)/2) + + assert manualintegrate(1 / x, x) == log(x) + assert manualintegrate(1 / (2*x + 3), x) == log(2*x + 3) / 2 + assert manualintegrate(log(x)**2 / x, x) == log(x)**3 / 3 + + assert_is_integral_of(x**x*(log(x)+1), x**x) + + +def test_manualintegrate_parts(): + assert manualintegrate(exp(x) * sin(x), x) == \ + (exp(x) * sin(x)) / 2 - (exp(x) * cos(x)) / 2 + assert manualintegrate(2*x*cos(x), x) == 2*x*sin(x) + 2*cos(x) + assert manualintegrate(x * log(x), x) == x**2*log(x)/2 - x**2/4 + assert manualintegrate(log(x), x) == x * log(x) - x + assert manualintegrate((3*x**2 + 5) * exp(x), x) == \ + 3*x**2*exp(x) - 6*x*exp(x) + 11*exp(x) + assert manualintegrate(atan(x), x) == x*atan(x) - log(x**2 + 1)/2 + + # Make sure _parts_rule doesn't pick u = constant but can pick dv = + # constant if necessary, e.g. for integrate(atan(x)) + assert _parts_rule(cos(x), x) == None + assert _parts_rule(exp(x), x) == None + assert _parts_rule(x**2, x) == None + result = _parts_rule(atan(x), x) + assert result[0] == atan(x) and result[1] == 1 + + +def test_manualintegrate_trigonometry(): + assert manualintegrate(sin(x), x) == -cos(x) + assert manualintegrate(tan(x), x) == -log(cos(x)) + + assert manualintegrate(sec(x), x) == log(sec(x) + tan(x)) + assert manualintegrate(csc(x), x) == -log(csc(x) + cot(x)) + + assert manualintegrate(sin(x) * cos(x), x) in [sin(x) ** 2 / 2, -cos(x)**2 / 2] + assert manualintegrate(-sec(x) * tan(x), x) == -sec(x) + assert manualintegrate(csc(x) * cot(x), x) == -csc(x) + assert manualintegrate(sec(x)**2, x) == tan(x) + assert manualintegrate(csc(x)**2, x) == -cot(x) + + assert manualintegrate(x * sec(x**2), x) == log(tan(x**2) + sec(x**2))/2 + assert manualintegrate(cos(x)*csc(sin(x)), x) == -log(cot(sin(x)) + csc(sin(x))) + assert manualintegrate(cos(3*x)*sec(x), x) == -x + sin(2*x) + assert manualintegrate(sin(3*x)*sec(x), x) == \ + -3*log(cos(x)) + 2*log(cos(x)**2) - 2*cos(x)**2 + + assert_is_integral_of(sinh(2*x), cosh(2*x)/2) + assert_is_integral_of(x*cosh(x**2), sinh(x**2)/2) + assert_is_integral_of(tanh(x), log(cosh(x))) + assert_is_integral_of(coth(x), log(sinh(x))) + f, F = sech(x), 2*atan(tanh(x/2)) + assert manualintegrate(f, x) == F + assert (F.diff(x) - f).rewrite(exp).simplify() == 0 # todo: equals returns None + f, F = csch(x), log(tanh(x/2)) + assert manualintegrate(f, x) == F + assert (F.diff(x) - f).rewrite(exp).simplify() == 0 + + +@slow +def test_manualintegrate_trigpowers(): + assert manualintegrate(sin(x)**2 * cos(x), x) == sin(x)**3 / 3 + assert manualintegrate(sin(x)**2 * cos(x) **2, x) == \ + x / 8 - sin(4*x) / 32 + assert manualintegrate(sin(x) * cos(x)**3, x) == -cos(x)**4 / 4 + assert manualintegrate(sin(x)**3 * cos(x)**2, x) == \ + cos(x)**5 / 5 - cos(x)**3 / 3 + + assert manualintegrate(tan(x)**3 * sec(x), x) == sec(x)**3/3 - sec(x) + assert manualintegrate(tan(x) * sec(x) **2, x) == sec(x)**2/2 + + assert manualintegrate(cot(x)**5 * csc(x), x) == \ + -csc(x)**5/5 + 2*csc(x)**3/3 - csc(x) + assert manualintegrate(cot(x)**2 * csc(x)**6, x) == \ + -cot(x)**7/7 - 2*cot(x)**5/5 - cot(x)**3/3 + + +@slow +def test_manualintegrate_inversetrig(): + # atan + assert manualintegrate(exp(x) / (1 + exp(2*x)), x) == atan(exp(x)) + assert manualintegrate(1 / (4 + 9 * x**2), x) == atan(3 * x/2) / 6 + assert manualintegrate(1 / (16 + 16 * x**2), x) == atan(x) / 16 + assert manualintegrate(1 / (4 + x**2), x) == atan(x / 2) / 2 + assert manualintegrate(1 / (1 + 4 * x**2), x) == atan(2*x) / 2 + ra = Symbol('a', real=True) + rb = Symbol('b', real=True) + assert manualintegrate(1/(ra + rb*x**2), x) == \ + Piecewise((atan(x/sqrt(ra/rb))/(rb*sqrt(ra/rb)), ra/rb > 0), + ((log(x - sqrt(-ra/rb)) - log(x + sqrt(-ra/rb)))/(2*sqrt(rb)*sqrt(-ra)), True)) + assert manualintegrate(1/(4 + rb*x**2), x) == \ + Piecewise((atan(x/(2*sqrt(1/rb)))/(2*rb*sqrt(1/rb)), 1/rb > 0), + (-I*(log(x - 2*sqrt(-1/rb)) - log(x + 2*sqrt(-1/rb)))/(4*sqrt(rb)), True)) + assert manualintegrate(1/(ra + 4*x**2), x) == \ + Piecewise((atan(2*x/sqrt(ra))/(2*sqrt(ra)), ra > 0), + ((log(x - sqrt(-ra)/2) - log(x + sqrt(-ra)/2))/(4*sqrt(-ra)), True)) + assert manualintegrate(1/(4 + 4*x**2), x) == atan(x) / 4 + + assert manualintegrate(1/(a + b*x**2), x) == Piecewise((atan(x/sqrt(a/b))/(b*sqrt(a/b)), Ne(a, 0)), + (-1/(b*x), True)) + + # asin + assert manualintegrate(1/sqrt(1-x**2), x) == asin(x) + assert manualintegrate(1/sqrt(4-4*x**2), x) == asin(x)/2 + assert manualintegrate(3/sqrt(1-9*x**2), x) == asin(3*x) + assert manualintegrate(1/sqrt(4-9*x**2), x) == asin(x*Rational(3, 2))/3 + + # asinh + assert manualintegrate(1/sqrt(x**2 + 1), x) == \ + asinh(x) + assert manualintegrate(1/sqrt(x**2 + 4), x) == \ + asinh(x/2) + assert manualintegrate(1/sqrt(4*x**2 + 4), x) == \ + asinh(x)/2 + assert manualintegrate(1/sqrt(4*x**2 + 1), x) == \ + asinh(2*x)/2 + assert manualintegrate(1/sqrt(ra*x**2 + 1), x) == \ + Piecewise((asin(x*sqrt(-ra))/sqrt(-ra), ra < 0), (asinh(sqrt(ra)*x)/sqrt(ra), ra > 0), (x, True)) + assert manualintegrate(1/sqrt(ra + x**2), x) == \ + Piecewise((asinh(x*sqrt(1/ra)), ra > 0), (log(2*x + 2*sqrt(ra + x**2)), True)) + + # log + assert manualintegrate(1/sqrt(x**2 - 1), x) == log(2*x + 2*sqrt(x**2 - 1)) + assert manualintegrate(1/sqrt(x**2 - 4), x) == log(2*x + 2*sqrt(x**2 - 4)) + assert manualintegrate(1/sqrt(4*x**2 - 4), x) == log(8*x + 4*sqrt(4*x**2 - 4))/2 + assert manualintegrate(1/sqrt(9*x**2 - 1), x) == log(18*x + 6*sqrt(9*x**2 - 1))/3 + assert manualintegrate(1/sqrt(ra*x**2 - 4), x) == \ + Piecewise((log(2*sqrt(ra)*sqrt(ra*x**2 - 4) + 2*ra*x)/sqrt(ra), Ne(ra, 0)), (-I*x/2, True)) + assert manualintegrate(1/sqrt(-ra + 4*x**2), x) == \ + Piecewise((asinh(2*x*sqrt(-1/ra))/2, ra < 0), (log(8*x + 4*sqrt(-ra + 4*x**2))/2, True)) + + # From https://www.wikiwand.com/en/List_of_integrals_of_inverse_trigonometric_functions + # asin + assert manualintegrate(asin(x), x) == x*asin(x) + sqrt(1 - x**2) + assert manualintegrate(asin(a*x), x) == Piecewise(((a*x*asin(a*x) + sqrt(-a**2*x**2 + 1))/a, Ne(a, 0)), (0, True)) + assert manualintegrate(x*asin(a*x), x) == \ + -a*Piecewise((-x*sqrt(-a**2*x**2 + 1)/(2*a**2) + + log(-2*a**2*x + 2*sqrt(-a**2)*sqrt(-a**2*x**2 + 1))/(2*a**2*sqrt(-a**2)), Ne(a**2, 0)), + (x**3/3, True))/2 + x**2*asin(a*x)/2 + # acos + assert manualintegrate(acos(x), x) == x*acos(x) - sqrt(1 - x**2) + assert manualintegrate(acos(a*x), x) == Piecewise(((a*x*acos(a*x) - sqrt(-a**2*x**2 + 1))/a, Ne(a, 0)), (pi*x/2, True)) + assert manualintegrate(x*acos(a*x), x) == \ + a*Piecewise((-x*sqrt(-a**2*x**2 + 1)/(2*a**2) + + log(-2*a**2*x + 2*sqrt(-a**2)*sqrt(-a**2*x**2 + 1))/(2*a**2*sqrt(-a**2)), Ne(a**2, 0)), + (x**3/3, True))/2 + x**2*acos(a*x)/2 + # atan + assert manualintegrate(atan(x), x) == x*atan(x) - log(x**2 + 1)/2 + assert manualintegrate(atan(a*x), x) == Piecewise(((a*x*atan(a*x) - log(a**2*x**2 + 1)/2)/a, Ne(a, 0)), (0, True)) + assert manualintegrate(x*atan(a*x), x) == -a*(x/a**2 - atan(x/sqrt(a**(-2)))/(a**4*sqrt(a**(-2))))/2 + x**2*atan(a*x)/2 + # acsc + assert manualintegrate(acsc(x), x) == x*acsc(x) + Integral(1/(x*sqrt(1 - 1/x**2)), x) + assert manualintegrate(acsc(a*x), x) == x*acsc(a*x) + Integral(1/(x*sqrt(1 - 1/(a**2*x**2))), x)/a + assert manualintegrate(x*acsc(a*x), x) == x**2*acsc(a*x)/2 + Integral(1/sqrt(1 - 1/(a**2*x**2)), x)/(2*a) + # asec + assert manualintegrate(asec(x), x) == x*asec(x) - Integral(1/(x*sqrt(1 - 1/x**2)), x) + assert manualintegrate(asec(a*x), x) == x*asec(a*x) - Integral(1/(x*sqrt(1 - 1/(a**2*x**2))), x)/a + assert manualintegrate(x*asec(a*x), x) == x**2*asec(a*x)/2 - Integral(1/sqrt(1 - 1/(a**2*x**2)), x)/(2*a) + # acot + assert manualintegrate(acot(x), x) == x*acot(x) + log(x**2 + 1)/2 + assert manualintegrate(acot(a*x), x) == Piecewise(((a*x*acot(a*x) + log(a**2*x**2 + 1)/2)/a, Ne(a, 0)), (pi*x/2, True)) + assert manualintegrate(x*acot(a*x), x) == a*(x/a**2 - atan(x/sqrt(a**(-2)))/(a**4*sqrt(a**(-2))))/2 + x**2*acot(a*x)/2 + + # piecewise + assert manualintegrate(1/sqrt(ra-rb*x**2), x) == \ + Piecewise((asin(x*sqrt(rb/ra))/sqrt(rb), And(-rb < 0, ra > 0)), + (asinh(x*sqrt(-rb/ra))/sqrt(-rb), And(-rb > 0, ra > 0)), + (log(-2*rb*x + 2*sqrt(-rb)*sqrt(ra - rb*x**2))/sqrt(-rb), Ne(rb, 0)), + (x/sqrt(ra), True)) + assert manualintegrate(1/sqrt(ra + rb*x**2), x) == \ + Piecewise((asin(x*sqrt(-rb/ra))/sqrt(-rb), And(ra > 0, rb < 0)), + (asinh(x*sqrt(rb/ra))/sqrt(rb), And(ra > 0, rb > 0)), + (log(2*sqrt(rb)*sqrt(ra + rb*x**2) + 2*rb*x)/sqrt(rb), Ne(rb, 0)), + (x/sqrt(ra), True)) + + +def test_manualintegrate_trig_substitution(): + assert manualintegrate(sqrt(16*x**2 - 9)/x, x) == \ + Piecewise((sqrt(16*x**2 - 9) - 3*acos(3/(4*x)), + And(x < Rational(3, 4), x > Rational(-3, 4)))) + assert manualintegrate(1/(x**4 * sqrt(25-x**2)), x) == \ + Piecewise((-sqrt(-x**2/25 + 1)/(125*x) - + (-x**2/25 + 1)**(3*S.Half)/(15*x**3), And(x < 5, x > -5))) + assert manualintegrate(x**7/(49*x**2 + 1)**(3 * S.Half), x) == \ + ((49*x**2 + 1)**(5*S.Half)/28824005 - + (49*x**2 + 1)**(3*S.Half)/5764801 + + 3*sqrt(49*x**2 + 1)/5764801 + 1/(5764801*sqrt(49*x**2 + 1))) + +def test_manualintegrate_trivial_substitution(): + assert manualintegrate((exp(x) - exp(-x))/x, x) == -Ei(-x) + Ei(x) + f = Function('f') + assert manualintegrate((f(x) - f(-x))/x, x) == \ + -Integral(f(-x)/x, x) + Integral(f(x)/x, x) + + +def test_manualintegrate_rational(): + assert manualintegrate(1/(4 - x**2), x) == -log(x - 2)/4 + log(x + 2)/4 + assert manualintegrate(1/(-1 + x**2), x) == log(x - 1)/2 - log(x + 1)/2 + + +def test_manualintegrate_special(): + f, F = 4*exp(-x**2/3), 2*sqrt(3)*sqrt(pi)*erf(sqrt(3)*x/3) + assert_is_integral_of(f, F) + f, F = 3*exp(4*x**2), 3*sqrt(pi)*erfi(2*x)/4 + assert_is_integral_of(f, F) + f, F = x**Rational(1, 3)*exp(-x/8), -16*uppergamma(Rational(4, 3), x/8) + assert_is_integral_of(f, F) + f, F = exp(2*x)/x, Ei(2*x) + assert_is_integral_of(f, F) + f, F = exp(1 + 2*x - x**2), sqrt(pi)*exp(2)*erf(x - 1)/2 + assert_is_integral_of(f, F) + f = sin(x**2 + 4*x + 1) + F = (sqrt(2)*sqrt(pi)*(-sin(3)*fresnelc(sqrt(2)*(2*x + 4)/(2*sqrt(pi))) + + cos(3)*fresnels(sqrt(2)*(2*x + 4)/(2*sqrt(pi))))/2) + assert_is_integral_of(f, F) + f, F = cos(4*x**2), sqrt(2)*sqrt(pi)*fresnelc(2*sqrt(2)*x/sqrt(pi))/4 + assert_is_integral_of(f, F) + f, F = sin(3*x + 2)/x, sin(2)*Ci(3*x) + cos(2)*Si(3*x) + assert_is_integral_of(f, F) + f, F = sinh(3*x - 2)/x, -sinh(2)*Chi(3*x) + cosh(2)*Shi(3*x) + assert_is_integral_of(f, F) + f, F = 5*cos(2*x - 3)/x, 5*cos(3)*Ci(2*x) + 5*sin(3)*Si(2*x) + assert_is_integral_of(f, F) + f, F = cosh(x/2)/x, Chi(x/2) + assert_is_integral_of(f, F) + f, F = cos(x**2)/x, Ci(x**2)/2 + assert_is_integral_of(f, F) + f, F = 1/log(2*x + 1), li(2*x + 1)/2 + assert_is_integral_of(f, F) + f, F = polylog(2, 5*x)/x, polylog(3, 5*x) + assert_is_integral_of(f, F) + f, F = 5/sqrt(3 - 2*sin(x)**2), 5*sqrt(3)*elliptic_f(x, Rational(2, 3))/3 + assert_is_integral_of(f, F) + f, F = sqrt(4 + 9*sin(x)**2), 2*elliptic_e(x, Rational(-9, 4)) + assert_is_integral_of(f, F) + + +def test_manualintegrate_derivative(): + assert manualintegrate(pi * Derivative(x**2 + 2*x + 3), x) == \ + pi * (x**2 + 2*x + 3) + assert manualintegrate(Derivative(x**2 + 2*x + 3, y), x) == \ + Integral(Derivative(x**2 + 2*x + 3, y)) + assert manualintegrate(Derivative(sin(x), x, x, x, y), x) == \ + Derivative(sin(x), x, x, y) + + +def test_manualintegrate_Heaviside(): + assert_is_integral_of(DiracDelta(3*x+2), Heaviside(3*x+2)/3) + assert_is_integral_of(DiracDelta(3*x, 0), Heaviside(3*x)/3) + assert manualintegrate(DiracDelta(a+b*x, 1), x) == \ + Piecewise((DiracDelta(a + b*x)/b, Ne(b, 0)), (x*DiracDelta(a, 1), True)) + assert_is_integral_of(DiracDelta(x/3-1, 2), 3*DiracDelta(x/3-1, 1)) + assert manualintegrate(Heaviside(x), x) == x*Heaviside(x) + assert manualintegrate(x*Heaviside(2), x) == x**2/2 + assert manualintegrate(x*Heaviside(-2), x) == 0 + assert manualintegrate(x*Heaviside( x), x) == x**2*Heaviside( x)/2 + assert manualintegrate(x*Heaviside(-x), x) == x**2*Heaviside(-x)/2 + assert manualintegrate(Heaviside(2*x + 4), x) == (x+2)*Heaviside(2*x + 4) + assert manualintegrate(x*Heaviside(x), x) == x**2*Heaviside(x)/2 + assert manualintegrate(Heaviside(x + 1)*Heaviside(1 - x)*x**2, x) == \ + ((x**3/3 + Rational(1, 3))*Heaviside(x + 1) - Rational(2, 3))*Heaviside(-x + 1) + + y = Symbol('y') + assert manualintegrate(sin(7 + x)*Heaviside(3*x - 7), x) == \ + (- cos(x + 7) + cos(Rational(28, 3)))*Heaviside(3*x - S(7)) + + assert manualintegrate(sin(y + x)*Heaviside(3*x - y), x) == \ + (cos(y*Rational(4, 3)) - cos(x + y))*Heaviside(3*x - y) + + +def test_manualintegrate_orthogonal_poly(): + n = symbols('n') + a, b = 7, Rational(5, 3) + polys = [jacobi(n, a, b, x), gegenbauer(n, a, x), chebyshevt(n, x), + chebyshevu(n, x), legendre(n, x), hermite(n, x), laguerre(n, x), + assoc_laguerre(n, a, x)] + for p in polys: + integral = manualintegrate(p, x) + for deg in [-2, -1, 0, 1, 3, 5, 8]: + # some accept negative "degree", some do not + try: + p_subbed = p.subs(n, deg) + except ValueError: + continue + assert (integral.subs(n, deg).diff(x) - p_subbed).expand() == 0 + + # can also integrate simple expressions with these polynomials + q = x*p.subs(x, 2*x + 1) + integral = manualintegrate(q, x) + for deg in [2, 4, 7]: + assert (integral.subs(n, deg).diff(x) - q.subs(n, deg)).expand() == 0 + + # cannot integrate with respect to any other parameter + t = symbols('t') + for i in range(len(p.args) - 1): + new_args = list(p.args) + new_args[i] = t + assert isinstance(manualintegrate(p.func(*new_args), t), Integral) + + +@slow +def test_issue_6799(): + r, x, phi = map(Symbol, 'r x phi'.split()) + n = Symbol('n', integer=True, positive=True) + + integrand = (cos(n*(x-phi))*cos(n*x)) + limits = (x, -pi, pi) + assert manualintegrate(integrand, x) == \ + ((n*x/2 + sin(2*n*x)/4)*cos(n*phi) - sin(n*phi)*cos(n*x)**2/2)/n + assert r * integrate(integrand, limits).trigsimp() / pi == r * cos(n * phi) + assert not integrate(integrand, limits).has(Dummy) + + +def test_issue_12251(): + assert manualintegrate(x**y, x) == Piecewise( + (x**(y + 1)/(y + 1), Ne(y, -1)), (log(x), True)) + + +def test_issue_3796(): + assert manualintegrate(diff(exp(x + x**2)), x) == exp(x + x**2) + assert integrate(x * exp(x**4), x, risch=False) == -I*sqrt(pi)*erf(I*x**2)/4 + + +def test_manual_true(): + assert integrate(exp(x) * sin(x), x, manual=True) == \ + (exp(x) * sin(x)) / 2 - (exp(x) * cos(x)) / 2 + assert integrate(sin(x) * cos(x), x, manual=True) in \ + [sin(x) ** 2 / 2, -cos(x)**2 / 2] + + +def test_issue_6746(): + y = Symbol('y') + n = Symbol('n') + assert manualintegrate(y**x, x) == Piecewise( + (y**x/log(y), Ne(log(y), 0)), (x, True)) + assert manualintegrate(y**(n*x), x) == Piecewise( + (Piecewise( + (y**(n*x)/log(y), Ne(log(y), 0)), + (n*x, True) + )/n, Ne(n, 0)), + (x, True)) + assert manualintegrate(exp(n*x), x) == Piecewise( + (exp(n*x)/n, Ne(n, 0)), (x, True)) + + y = Symbol('y', positive=True) + assert manualintegrate((y + 1)**x, x) == (y + 1)**x/log(y + 1) + y = Symbol('y', zero=True) + assert manualintegrate((y + 1)**x, x) == x + y = Symbol('y') + n = Symbol('n', nonzero=True) + assert manualintegrate(y**(n*x), x) == Piecewise( + (y**(n*x)/log(y), Ne(log(y), 0)), (n*x, True))/n + y = Symbol('y', positive=True) + assert manualintegrate((y + 1)**(n*x), x) == \ + (y + 1)**(n*x)/(n*log(y + 1)) + a = Symbol('a', negative=True) + b = Symbol('b') + assert manualintegrate(1/(a + b*x**2), x) == atan(x/sqrt(a/b))/(b*sqrt(a/b)) + b = Symbol('b', negative=True) + assert manualintegrate(1/(a + b*x**2), x) == \ + atan(x/(sqrt(-a)*sqrt(-1/b)))/(b*sqrt(-a)*sqrt(-1/b)) + assert manualintegrate(1/((x**a + y**b + 4)*sqrt(a*x**2 + 1)), x) == \ + y**(-b)*Integral(x**(-a)/(y**(-b)*sqrt(a*x**2 + 1) + + x**(-a)*sqrt(a*x**2 + 1) + 4*x**(-a)*y**(-b)*sqrt(a*x**2 + 1)), x) + assert manualintegrate(1/((x**2 + 4)*sqrt(4*x**2 + 1)), x) == \ + Integral(1/((x**2 + 4)*sqrt(4*x**2 + 1)), x) + assert manualintegrate(1/(x - a**x + x*b**2), x) == \ + Integral(1/(-a**x + b**2*x + x), x) + + +@slow +def test_issue_2850(): + assert manualintegrate(asin(x)*log(x), x) == -x*asin(x) - sqrt(-x**2 + 1) \ + + (x*asin(x) + sqrt(-x**2 + 1))*log(x) - Integral(sqrt(-x**2 + 1)/x, x) + assert manualintegrate(acos(x)*log(x), x) == -x*acos(x) + sqrt(-x**2 + 1) + \ + (x*acos(x) - sqrt(-x**2 + 1))*log(x) + Integral(sqrt(-x**2 + 1)/x, x) + assert manualintegrate(atan(x)*log(x), x) == -x*atan(x) + (x*atan(x) - \ + log(x**2 + 1)/2)*log(x) + log(x**2 + 1)/2 + Integral(log(x**2 + 1)/x, x)/2 + + +def test_issue_9462(): + assert manualintegrate(sin(2*x)*exp(x), x) == exp(x)*sin(2*x)/5 - 2*exp(x)*cos(2*x)/5 + assert not integral_steps(sin(2*x)*exp(x), x).contains_dont_know() + assert manualintegrate((x - 3) / (x**2 - 2*x + 2)**2, x) == \ + Integral(x/(x**4 - 4*x**3 + 8*x**2 - 8*x + 4), x) \ + - 3*Integral(1/(x**4 - 4*x**3 + 8*x**2 - 8*x + 4), x) + + +def test_cyclic_parts(): + f = cos(x)*exp(x/4) + F = 16*exp(x/4)*sin(x)/17 + 4*exp(x/4)*cos(x)/17 + assert manualintegrate(f, x) == F and F.diff(x) == f + f = x*cos(x)*exp(x/4) + F = (x*(16*exp(x/4)*sin(x)/17 + 4*exp(x/4)*cos(x)/17) - + 128*exp(x/4)*sin(x)/289 + 240*exp(x/4)*cos(x)/289) + assert manualintegrate(f, x) == F and F.diff(x) == f + + +@slow +def test_issue_10847_slow(): + assert manualintegrate((4*x**4 + 4*x**3 + 16*x**2 + 12*x + 8) + / (x**6 + 2*x**5 + 3*x**4 + 4*x**3 + 3*x**2 + 2*x + 1), x) == \ + 2*x/(x**2 + 1) + 3*atan(x) - 1/(x**2 + 1) - 3/(x + 1) + + +@slow +def test_issue_10847(): + + assert manualintegrate(x**2 / (x**2 - c), x) == \ + c*Piecewise((atan(x/sqrt(-c))/sqrt(-c), Ne(c, 0)), (-1/x, True)) + x + + rc = Symbol('c', real=True) + assert manualintegrate(x**2 / (x**2 - rc), x) == \ + rc*Piecewise((atan(x/sqrt(-rc))/sqrt(-rc), rc < 0), + ((log(-sqrt(rc) + x) - log(sqrt(rc) + x))/(2*sqrt(rc)), True)) + x + + assert manualintegrate(sqrt(x - y) * log(z / x), x) == \ + 4*y**2*Piecewise((atan(sqrt(x - y)/sqrt(y))/sqrt(y), Ne(y, 0)), + (-1/sqrt(x - y), True))/3 - 4*y*sqrt(x - y)/3 + \ + 2*(x - y)**Rational(3, 2)*log(z/x)/3 + 4*(x - y)**Rational(3, 2)/9 + ry = Symbol('y', real=True) + rz = Symbol('z', real=True) + assert manualintegrate(sqrt(x - ry) * log(rz / x), x) == \ + 4*ry**2*Piecewise((atan(sqrt(x - ry)/sqrt(ry))/sqrt(ry), ry > 0), + ((log(-sqrt(-ry) + sqrt(x - ry)) - log(sqrt(-ry) + sqrt(x - ry)))/(2*sqrt(-ry)), True))/3 \ + - 4*ry*sqrt(x - ry)/3 + 2*(x - ry)**Rational(3, 2)*log(rz/x)/3 \ + + 4*(x - ry)**Rational(3, 2)/9 + + assert manualintegrate(sqrt(x) * log(x), x) == 2*x**Rational(3, 2)*log(x)/3 - 4*x**Rational(3, 2)/9 + + result = manualintegrate(sqrt(a*x + b) / x, x) + assert result == Piecewise((-2*b*Piecewise( + (-atan(sqrt(a*x + b)/sqrt(-b))/sqrt(-b), Ne(b, 0)), + (1/sqrt(a*x + b), True)) + 2*sqrt(a*x + b), Ne(a, 0)), + (sqrt(b)*log(x), True)) + assert piecewise_fold(result) == Piecewise( + (2*b*atan(sqrt(a*x + b)/sqrt(-b))/sqrt(-b) + 2*sqrt(a*x + b), Ne(a, 0) & Ne(b, 0)), + (-2*b/sqrt(a*x + b) + 2*sqrt(a*x + b), Ne(a, 0)), + (sqrt(b)*log(x), True)) + + ra = Symbol('a', real=True) + rb = Symbol('b', real=True) + assert manualintegrate(sqrt(ra*x + rb) / x, x) == \ + Piecewise( + (-2*rb*Piecewise( + (-atan(sqrt(ra*x + rb)/sqrt(-rb))/sqrt(-rb), rb < 0), + (-I*(log(-sqrt(rb) + sqrt(ra*x + rb)) - log(sqrt(rb) + sqrt(ra*x + rb)))/(2*sqrt(-rb)), True)) + + 2*sqrt(ra*x + rb), Ne(ra, 0)), + (sqrt(rb)*log(x), True)) + + assert expand(manualintegrate(sqrt(ra*x + rb) / (x + rc), x)) == \ + Piecewise((-2*ra*rc*Piecewise((atan(sqrt(ra*x + rb)/sqrt(ra*rc - rb))/sqrt(ra*rc - rb), ra*rc - rb > 0), + (log(-sqrt(-ra*rc + rb) + sqrt(ra*x + rb))/(2*sqrt(-ra*rc + rb)) - + log(sqrt(-ra*rc + rb) + sqrt(ra*x + rb))/(2*sqrt(-ra*rc + rb)), True)) + + 2*rb*Piecewise((atan(sqrt(ra*x + rb)/sqrt(ra*rc - rb))/sqrt(ra*rc - rb), ra*rc - rb > 0), + (log(-sqrt(-ra*rc + rb) + sqrt(ra*x + rb))/(2*sqrt(-ra*rc + rb)) - + log(sqrt(-ra*rc + rb) + sqrt(ra*x + rb))/(2*sqrt(-ra*rc + rb)), True)) + + 2*sqrt(ra*x + rb), Ne(ra, 0)), (sqrt(rb)*log(rc + x), True)) + + assert manualintegrate(sqrt(2*x + 3) / (x + 1), x) == 2*sqrt(2*x + 3) - log(sqrt(2*x + 3) + 1) + log(sqrt(2*x + 3) - 1) + assert manualintegrate(sqrt(2*x + 3) / 2 * x, x) == (2*x + 3)**Rational(5, 2)/20 - (2*x + 3)**Rational(3, 2)/4 + assert manualintegrate(x**Rational(3,2) * log(x), x) == 2*x**Rational(5,2)*log(x)/5 - 4*x**Rational(5,2)/25 + assert manualintegrate(x**(-3) * log(x), x) == -log(x)/(2*x**2) - 1/(4*x**2) + assert manualintegrate(log(y)/(y**2*(1 - 1/y)), y) == \ + log(y)*log(-1 + 1/y) - Integral(log(-1 + 1/y)/y, y) + + +def test_issue_12899(): + assert manualintegrate(f(x,y).diff(x),y) == Integral(Derivative(f(x,y),x),y) + assert manualintegrate(f(x,y).diff(y).diff(x),y) == Derivative(f(x,y),x) + + +def test_constant_independent_of_symbol(): + assert manualintegrate(Integral(y, (x, 1, 2)), x) == \ + x*Integral(y, (x, 1, 2)) + + +def test_issue_12641(): + assert manualintegrate(sin(2*x), x) == -cos(2*x)/2 + assert manualintegrate(cos(x)*sin(2*x), x) == -2*cos(x)**3/3 + assert manualintegrate((sin(2*x)*cos(x))/(1 + cos(x)), x) == \ + -2*log(cos(x) + 1) - cos(x)**2 + 2*cos(x) + + +@slow +def test_issue_13297(): + assert manualintegrate(sin(x) * cos(x)**5, x) == -cos(x)**6 / 6 + + +def test_issue_14470(): + assert_is_integral_of(1/(x*sqrt(x + 1)), log(sqrt(x + 1) - 1) - log(sqrt(x + 1) + 1)) + + +@slow +def test_issue_9858(): + assert manualintegrate(exp(x)*cos(exp(x)), x) == sin(exp(x)) + assert manualintegrate(exp(2*x)*cos(exp(x)), x) == \ + exp(x)*sin(exp(x)) + cos(exp(x)) + res = manualintegrate(exp(10*x)*sin(exp(x)), x) + assert not res.has(Integral) + assert res.diff(x) == exp(10*x)*sin(exp(x)) + # an example with many similar integrations by parts + assert manualintegrate(sum(x*exp(k*x) for k in range(1, 8)), x) == ( + x*exp(7*x)/7 + x*exp(6*x)/6 + x*exp(5*x)/5 + x*exp(4*x)/4 + + x*exp(3*x)/3 + x*exp(2*x)/2 + x*exp(x) - exp(7*x)/49 -exp(6*x)/36 - + exp(5*x)/25 - exp(4*x)/16 - exp(3*x)/9 - exp(2*x)/4 - exp(x)) + + +def test_issue_8520(): + assert manualintegrate(x/(x**4 + 1), x) == atan(x**2)/2 + assert manualintegrate(x**2/(x**6 + 25), x) == atan(x**3/5)/15 + f = x/(9*x**4 + 4)**2 + assert manualintegrate(f, x).diff(x).factor() == f + + +def test_manual_subs(): + x, y = symbols('x y') + expr = log(x) + exp(x) + # if log(x) is y, then exp(y) is x + assert manual_subs(expr, log(x), y) == y + exp(exp(y)) + # if exp(x) is y, then log(y) need not be x + assert manual_subs(expr, exp(x), y) == log(x) + y + + raises(ValueError, lambda: manual_subs(expr, x)) + raises(ValueError, lambda: manual_subs(expr, exp(x), x, y)) + + +@slow +def test_issue_15471(): + f = log(x)*cos(log(x))/x**Rational(3, 4) + F = -128*x**Rational(1, 4)*sin(log(x))/289 + 240*x**Rational(1, 4)*cos(log(x))/289 + (16*x**Rational(1, 4)*sin(log(x))/17 + 4*x**Rational(1, 4)*cos(log(x))/17)*log(x) + assert_is_integral_of(f, F) + + +def test_quadratic_denom(): + f = (5*x + 2)/(3*x**2 - 2*x + 8) + assert manualintegrate(f, x) == 5*log(3*x**2 - 2*x + 8)/6 + 11*sqrt(23)*atan(3*sqrt(23)*(x - Rational(1, 3))/23)/69 + g = 3/(2*x**2 + 3*x + 1) + assert manualintegrate(g, x) == 3*log(4*x + 2) - 3*log(4*x + 4) + +def test_issue_22757(): + assert manualintegrate(sin(x), y) == y * sin(x) + + +def test_issue_23348(): + steps = integral_steps(tan(x), x) + constant_times_step = steps.substep.substep + assert constant_times_step.integrand == constant_times_step.constant * constant_times_step.other + + +def test_issue_23566(): + i = Integral(1/sqrt(x**2 - 1), (x, -2, -1)).doit(manual=True) + assert i == -log(4 - 2*sqrt(3)) + log(2) + assert str(i.n()) == '1.31695789692482' + + +def test_issue_25093(): + ap = Symbol('ap', positive=True) + an = Symbol('an', negative=True) + assert manualintegrate(exp(a*x**2 + b), x) == sqrt(pi)*exp(b)*erfi(sqrt(a)*x)/(2*sqrt(a)) + assert manualintegrate(exp(ap*x**2 + b), x) == sqrt(pi)*exp(b)*erfi(sqrt(ap)*x)/(2*sqrt(ap)) + assert manualintegrate(exp(an*x**2 + b), x) == -sqrt(pi)*exp(b)*erf(an*x/sqrt(-an))/(2*sqrt(-an)) + assert manualintegrate(sin(a*x**2 + b), x) == ( + sqrt(2)*sqrt(pi)*(sin(b)*fresnelc(sqrt(2)*sqrt(a)*x/sqrt(pi)) + + cos(b)*fresnels(sqrt(2)*sqrt(a)*x/sqrt(pi)))/(2*sqrt(a))) + assert manualintegrate(cos(a*x**2 + b), x) == ( + sqrt(2)*sqrt(pi)*(-sin(b)*fresnels(sqrt(2)*sqrt(a)*x/sqrt(pi)) + + cos(b)*fresnelc(sqrt(2)*sqrt(a)*x/sqrt(pi)))/(2*sqrt(a))) + + +def test_nested_pow(): + assert_is_integral_of(sqrt(x**2), x*sqrt(x**2)/2) + assert_is_integral_of(sqrt(x**(S(5)/3)), 6*x*sqrt(x**(S(5)/3))/11) + assert_is_integral_of(1/sqrt(x**2), x*log(x)/sqrt(x**2)) + assert_is_integral_of(x*sqrt(x**(-4)), x**2*sqrt(x**-4)*log(x)) + f = (c*(a+b*x)**d)**e + F1 = (c*(a + b*x)**d)**e*(a/b + x)/(d*e + 1) + F2 = (c*(a + b*x)**d)**e*(a/b + x)*log(a/b + x) + assert manualintegrate(f, x) == \ + Piecewise((Piecewise((F1, Ne(d*e, -1)), (F2, True)), Ne(b, 0)), (x*(a**d*c)**e, True)) + assert F1.diff(x).equals(f) + assert F2.diff(x).subs(d*e, -1).equals(f) + + +def test_manualintegrate_sqrt_linear(): + assert_is_integral_of((5*x**3+4)/sqrt(2+3*x), + 10*(3*x + 2)**(S(7)/2)/567 - 4*(3*x + 2)**(S(5)/2)/27 + + 40*(3*x + 2)**(S(3)/2)/81 + 136*sqrt(3*x + 2)/81) + assert manualintegrate(x/sqrt(a+b*x)**3, x) == \ + Piecewise((Mul(2, b**-2, a/sqrt(a + b*x) + sqrt(a + b*x)), Ne(b, 0)), (x**2/(2*a**(S(3)/2)), True)) + assert_is_integral_of((sqrt(3*x+3)+1)/((2*x+2)**(1/S(3))+1), + 3*sqrt(6)*(2*x + 2)**(S(7)/6)/14 - 3*sqrt(6)*(2*x + 2)**(S(5)/6)/10 - + 3*sqrt(6)*(2*x + 2)**(S.One/6)/2 + 3*(2*x + 2)**(S(2)/3)/4 - 3*(2*x + 2)**(S.One/3)/2 + + sqrt(6)*sqrt(2*x + 2)/2 + 3*log((2*x + 2)**(S.One/3) + 1)/2 + + 3*sqrt(6)*atan((2*x + 2)**(S.One/6))/2) + assert_is_integral_of(sqrt(x+sqrt(x)), + 2*sqrt(sqrt(x) + x)*(sqrt(x)/12 + x/3 - S(1)/8) + log(2*sqrt(x) + 2*sqrt(sqrt(x) + x) + 1)/8) + assert_is_integral_of(sqrt(2*x+3+sqrt(4*x+5))**3, + sqrt(2*x + sqrt(4*x + 5) + 3) * + (9*x/10 + 11*(4*x + 5)**(S(3)/2)/40 + sqrt(4*x + 5)/40 + (4*x + 5)**2/10 + S(11)/10)/2) + + +def test_manualintegrate_sqrt_quadratic(): + assert_is_integral_of(1/sqrt((x - I)**2-1), log(2*x + 2*sqrt(x**2 - 2*I*x - 2) - 2*I)) + assert_is_integral_of(1/sqrt(3*x**2+4*x+5), sqrt(3)*asinh(3*sqrt(11)*(x + S(2)/3)/11)/3) + assert_is_integral_of(1/sqrt(-3*x**2+4*x+5), sqrt(3)*asin(3*sqrt(19)*(x - S(2)/3)/19)/3) + assert_is_integral_of(1/sqrt(3*x**2+4*x-5), sqrt(3)*log(6*x + 2*sqrt(3)*sqrt(3*x**2 + 4*x - 5) + 4)/3) + assert_is_integral_of(1/sqrt(4*x**2-4*x+1), (x - S.Half)*log(x - S.Half)/(2*sqrt((x - S.Half)**2))) + assert manualintegrate(1/sqrt(a+b*x+c*x**2), x) == \ + Piecewise((log(b + 2*sqrt(c)*sqrt(a + b*x + c*x**2) + 2*c*x)/sqrt(c), Ne(c, 0) & Ne(a - b**2/(4*c), 0)), + ((b/(2*c) + x)*log(b/(2*c) + x)/sqrt(c*(b/(2*c) + x)**2), Ne(c, 0)), + (2*sqrt(a + b*x)/b, Ne(b, 0)), (x/sqrt(a), True)) + + assert_is_integral_of((7*x+6)/sqrt(3*x**2+4*x+5), + 7*sqrt(3*x**2 + 4*x + 5)/3 + 4*sqrt(3)*asinh(3*sqrt(11)*(x + S(2)/3)/11)/9) + assert_is_integral_of((7*x+6)/sqrt(-3*x**2+4*x+5), + -7*sqrt(-3*x**2 + 4*x + 5)/3 + 32*sqrt(3)*asin(3*sqrt(19)*(x - S(2)/3)/19)/9) + assert_is_integral_of((7*x+6)/sqrt(3*x**2+4*x-5), + 7*sqrt(3*x**2 + 4*x - 5)/3 + 4*sqrt(3)*log(6*x + 2*sqrt(3)*sqrt(3*x**2 + 4*x - 5) + 4)/9) + assert manualintegrate((d+e*x)/sqrt(a+b*x+c*x**2), x) == \ + Piecewise(((-b*e/(2*c) + d) * + Piecewise((log(b + 2*sqrt(c)*sqrt(a + b*x + c*x**2) + 2*c*x)/sqrt(c), Ne(a - b**2/(4*c), 0)), + ((b/(2*c) + x)*log(b/(2*c) + x)/sqrt(c*(b/(2*c) + x)**2), True)) + + e*sqrt(a + b*x + c*x**2)/c, Ne(c, 0)), + ((2*d*sqrt(a + b*x) + 2*e*(-a*sqrt(a + b*x) + (a + b*x)**(S(3)/2)/3)/b)/b, Ne(b, 0)), + ((d*x + e*x**2/2)/sqrt(a), True)) + + assert manualintegrate((3*x**3-x**2+2*x-4)/sqrt(x**2-3*x+2), x) == \ + sqrt(x**2 - 3*x + 2)*(x**2 + 13*x/4 + S(101)/8) + 135*log(2*x + 2*sqrt(x**2 - 3*x + 2) - 3)/16 + + assert_is_integral_of(sqrt(53225*x**2-66732*x+23013), + (x/2 - S(16683)/53225)*sqrt(53225*x**2 - 66732*x + 23013) + + 111576969*sqrt(2129)*asinh(53225*x/10563 - S(11122)/3521)/1133160250) + assert manualintegrate(sqrt(a+c*x**2), x) == \ + Piecewise((a*Piecewise((log(2*sqrt(c)*sqrt(a + c*x**2) + 2*c*x)/sqrt(c), Ne(a, 0)), + (x*log(x)/sqrt(c*x**2), True))/2 + x*sqrt(a + c*x**2)/2, Ne(c, 0)), + (sqrt(a)*x, True)) + assert manualintegrate(sqrt(a+b*x+c*x**2), x) == \ + Piecewise(((a/2 - b**2/(8*c)) * + Piecewise((log(b + 2*sqrt(c)*sqrt(a + b*x + c*x**2) + 2*c*x)/sqrt(c), Ne(a - b**2/(4*c), 0)), + ((b/(2*c) + x)*log(b/(2*c) + x)/sqrt(c*(b/(2*c) + x)**2), True)) + + (b/(4*c) + x/2)*sqrt(a + b*x + c*x**2), Ne(c, 0)), + (2*(a + b*x)**(S(3)/2)/(3*b), Ne(b, 0)), + (sqrt(a)*x, True)) + + assert_is_integral_of(x*sqrt(x**2+2*x+4), + (x**2/3 + x/6 + S(5)/6)*sqrt(x**2 + 2*x + 4) - 3*asinh(sqrt(3)*(x + 1)/3)/2) + + +def test_mul_pow_derivative(): + assert_is_integral_of(x*sec(x)*tan(x), x*sec(x) - log(tan(x) + sec(x))) + assert_is_integral_of(x*sec(x)**2, x*tan(x) + log(cos(x))) + assert_is_integral_of(x**3*Derivative(f(x), (x, 4)), + x**3*Derivative(f(x), (x, 3)) - 3*x**2*Derivative(f(x), (x, 2)) + + 6*x*Derivative(f(x), x) - 6*f(x)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_meijerint.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_meijerint.py new file mode 100644 index 0000000000000000000000000000000000000000..899bc96e63d6dd5bccd52856f15d3085e87d5807 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_meijerint.py @@ -0,0 +1,774 @@ +from sympy.core.function import expand_func +from sympy.core.numbers import (I, Rational, oo, pi) +from sympy.core.singleton import S +from sympy.core.sorting import default_sort_key +from sympy.functions.elementary.complexes import Abs, arg, re, unpolarify +from sympy.functions.elementary.exponential import (exp, exp_polar, log) +from sympy.functions.elementary.hyperbolic import cosh, acosh, sinh +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise, piecewise_fold +from sympy.functions.elementary.trigonometric import (cos, sin, sinc, asin) +from sympy.functions.special.error_functions import (erf, erfc) +from sympy.functions.special.gamma_functions import (gamma, polygamma) +from sympy.functions.special.hyper import (hyper, meijerg) +from sympy.integrals.integrals import (Integral, integrate) +from sympy.simplify.hyperexpand import hyperexpand +from sympy.simplify.simplify import simplify +from sympy.integrals.meijerint import (_rewrite_single, _rewrite1, + meijerint_indefinite, _inflate_g, _create_lookup_table, + meijerint_definite, meijerint_inversion) +from sympy.testing.pytest import slow +from sympy.core.random import (verify_numerically, + random_complex_number as randcplx) +from sympy.abc import x, y, a, b, c, d, s, t, z + + +def test_rewrite_single(): + def t(expr, c, m): + e = _rewrite_single(meijerg([a], [b], [c], [d], expr), x) + assert e is not None + assert isinstance(e[0][0][2], meijerg) + assert e[0][0][2].argument.as_coeff_mul(x) == (c, (m,)) + + def tn(expr): + assert _rewrite_single(meijerg([a], [b], [c], [d], expr), x) is None + + t(x, 1, x) + t(x**2, 1, x**2) + t(x**2 + y*x**2, y + 1, x**2) + tn(x**2 + x) + tn(x**y) + + def u(expr, x): + from sympy.core.add import Add + r = _rewrite_single(expr, x) + e = Add(*[res[0]*res[2] for res in r[0]]).replace( + exp_polar, exp) # XXX Hack? + assert verify_numerically(e, expr, x) + + u(exp(-x)*sin(x), x) + + # The following has stopped working because hyperexpand changed slightly. + # It is probably not worth fixing + #u(exp(-x)*sin(x)*cos(x), x) + + # This one cannot be done numerically, since it comes out as a g-function + # of argument 4*pi + # NOTE This also tests a bug in inverse mellin transform (which used to + # turn exp(4*pi*I*t) into a factor of exp(4*pi*I)**t instead of + # exp_polar). + #u(exp(x)*sin(x), x) + assert _rewrite_single(exp(x)*sin(x), x) == \ + ([(-sqrt(2)/(2*sqrt(pi)), 0, + meijerg(((Rational(-1, 2), 0, Rational(1, 4), S.Half, Rational(3, 4)), (1,)), + ((), (Rational(-1, 2), 0)), 64*exp_polar(-4*I*pi)/x**4))], True) + + +def test_rewrite1(): + assert _rewrite1(x**3*meijerg([a], [b], [c], [d], x**2 + y*x**2)*5, x) == \ + (5, x**3, [(1, 0, meijerg([a], [b], [c], [d], x**2*(y + 1)))], True) + + +def test_meijerint_indefinite_numerically(): + def t(fac, arg): + g = meijerg([a], [b], [c], [d], arg)*fac + subs = {a: randcplx()/10, b: randcplx()/10 + I, + c: randcplx(), d: randcplx()} + integral = meijerint_indefinite(g, x) + assert integral is not None + assert verify_numerically(g.subs(subs), integral.diff(x).subs(subs), x) + t(1, x) + t(2, x) + t(1, 2*x) + t(1, x**2) + t(5, x**S('3/2')) + t(x**3, x) + t(3*x**S('3/2'), 4*x**S('7/3')) + + +def test_meijerint_definite(): + v, b = meijerint_definite(x, x, 0, 0) + assert v.is_zero and b is True + v, b = meijerint_definite(x, x, oo, oo) + assert v.is_zero and b is True + + +def test_inflate(): + subs = {a: randcplx()/10, b: randcplx()/10 + I, c: randcplx(), + d: randcplx(), y: randcplx()/10} + + def t(a, b, arg, n): + from sympy.core.mul import Mul + m1 = meijerg(a, b, arg) + m2 = Mul(*_inflate_g(m1, n)) + # NOTE: (the random number)**9 must still be on the principal sheet. + # Thus make b&d small to create random numbers of small imaginary part. + return verify_numerically(m1.subs(subs), m2.subs(subs), x, b=0.1, d=-0.1) + assert t([[a], [b]], [[c], [d]], x, 3) + assert t([[a, y], [b]], [[c], [d]], x, 3) + assert t([[a], [b]], [[c, y], [d]], 2*x**3, 3) + + +def test_recursive(): + from sympy.core.symbol import symbols + a, b, c = symbols('a b c', positive=True) + r = exp(-(x - a)**2)*exp(-(x - b)**2) + e = integrate(r, (x, 0, oo), meijerg=True) + assert simplify(e.expand()) == ( + sqrt(2)*sqrt(pi)*( + (erf(sqrt(2)*(a + b)/2) + 1)*exp(-a**2/2 + a*b - b**2/2))/4) + e = integrate(exp(-(x - a)**2)*exp(-(x - b)**2)*exp(c*x), (x, 0, oo), meijerg=True) + assert simplify(e) == ( + sqrt(2)*sqrt(pi)*(erf(sqrt(2)*(2*a + 2*b + c)/4) + 1)*exp(-a**2 - b**2 + + (2*a + 2*b + c)**2/8)/4) + assert simplify(integrate(exp(-(x - a - b - c)**2), (x, 0, oo), meijerg=True)) == \ + sqrt(pi)/2*(1 + erf(a + b + c)) + assert simplify(integrate(exp(-(x + a + b + c)**2), (x, 0, oo), meijerg=True)) == \ + sqrt(pi)/2*(1 - erf(a + b + c)) + + +@slow +def test_meijerint(): + from sympy.core.function import expand + from sympy.core.symbol import symbols + s, t, mu = symbols('s t mu', real=True) + assert integrate(meijerg([], [], [0], [], s*t) + *meijerg([], [], [mu/2], [-mu/2], t**2/4), + (t, 0, oo)).is_Piecewise + s = symbols('s', positive=True) + assert integrate(x**s*meijerg([[], []], [[0], []], x), (x, 0, oo)) == \ + gamma(s + 1) + assert integrate(x**s*meijerg([[], []], [[0], []], x), (x, 0, oo), + meijerg=True) == gamma(s + 1) + assert isinstance(integrate(x**s*meijerg([[], []], [[0], []], x), + (x, 0, oo), meijerg=False), + Integral) + + assert meijerint_indefinite(exp(x), x) == exp(x) + + # TODO what simplifications should be done automatically? + # This tests "extra case" for antecedents_1. + a, b = symbols('a b', positive=True) + assert simplify(meijerint_definite(x**a, x, 0, b)[0]) == \ + b**(a + 1)/(a + 1) + + # This tests various conditions and expansions: + assert meijerint_definite((x + 1)**3*exp(-x), x, 0, oo) == (16, True) + + # Again, how about simplifications? + sigma, mu = symbols('sigma mu', positive=True) + i, c = meijerint_definite(exp(-((x - mu)/(2*sigma))**2), x, 0, oo) + assert simplify(i) == sqrt(pi)*sigma*(2 - erfc(mu/(2*sigma))) + assert c == True + + i, _ = meijerint_definite(exp(-mu*x)*exp(sigma*x), x, 0, oo) + # TODO it would be nice to test the condition + assert simplify(i) == 1/(mu - sigma) + + # Test substitutions to change limits + assert meijerint_definite(exp(x), x, -oo, 2) == (exp(2), True) + # Note: causes a NaN in _check_antecedents + assert expand(meijerint_definite(exp(x), x, 0, I)[0]) == exp(I) - 1 + assert expand(meijerint_definite(exp(-x), x, 0, x)[0]) == \ + 1 - exp(-exp(I*arg(x))*abs(x)) + + # Test -oo to oo + assert meijerint_definite(exp(-x**2), x, -oo, oo) == (sqrt(pi), True) + assert meijerint_definite(exp(-abs(x)), x, -oo, oo) == (2, True) + assert meijerint_definite(exp(-(2*x - 3)**2), x, -oo, oo) == \ + (sqrt(pi)/2, True) + assert meijerint_definite(exp(-abs(2*x - 3)), x, -oo, oo) == (1, True) + assert meijerint_definite(exp(-((x - mu)/sigma)**2/2)/sqrt(2*pi*sigma**2), + x, -oo, oo) == (1, True) + assert meijerint_definite(sinc(x)**2, x, -oo, oo) == (pi, True) + + # Test one of the extra conditions for 2 g-functinos + assert meijerint_definite(exp(-x)*sin(x), x, 0, oo) == (S.Half, True) + + # Test a bug + def res(n): + return (1/(1 + x**2)).diff(x, n).subs(x, 1)*(-1)**n + for n in range(6): + assert integrate(exp(-x)*sin(x)*x**n, (x, 0, oo), meijerg=True) == \ + res(n) + + # This used to test trigexpand... now it is done by linear substitution + assert simplify(integrate(exp(-x)*sin(x + a), (x, 0, oo), meijerg=True) + ) == sqrt(2)*sin(a + pi/4)/2 + + # Test the condition 14 from prudnikov. + # (This is besselj*besselj in disguise, to stop the product from being + # recognised in the tables.) + a, b, s = symbols('a b s') + assert meijerint_definite(meijerg([], [], [a/2], [-a/2], x/4) + *meijerg([], [], [b/2], [-b/2], x/4)*x**(s - 1), x, 0, oo + ) == ( + (4*2**(2*s - 2)*gamma(-2*s + 1)*gamma(a/2 + b/2 + s) + /(gamma(-a/2 + b/2 - s + 1)*gamma(a/2 - b/2 - s + 1) + *gamma(a/2 + b/2 - s + 1)), + (re(s) < 1) & (re(s) < S(1)/2) & (re(a)/2 + re(b)/2 + re(s) > 0))) + + # test a bug + assert integrate(sin(x**a)*sin(x**b), (x, 0, oo), meijerg=True) == \ + Integral(sin(x**a)*sin(x**b), (x, 0, oo)) + + # test better hyperexpand + assert integrate(exp(-x**2)*log(x), (x, 0, oo), meijerg=True) == \ + (sqrt(pi)*polygamma(0, S.Half)/4).expand() + + # Test hyperexpand bug. + from sympy.functions.special.gamma_functions import lowergamma + n = symbols('n', integer=True) + assert simplify(integrate(exp(-x)*x**n, x, meijerg=True)) == \ + lowergamma(n + 1, x) + + # Test a bug with argument 1/x + alpha = symbols('alpha', positive=True) + assert meijerint_definite((2 - x)**alpha*sin(alpha/x), x, 0, 2) == \ + (sqrt(pi)*alpha*gamma(alpha + 1)*meijerg(((), (alpha/2 + S.Half, + alpha/2 + 1)), ((0, 0, S.Half), (Rational(-1, 2),)), alpha**2/16)/4, True) + + # test a bug related to 3016 + a, s = symbols('a s', positive=True) + assert simplify(integrate(x**s*exp(-a*x**2), (x, -oo, oo))) == \ + a**(-s/2 - S.Half)*((-1)**s + 1)*gamma(s/2 + S.Half)/2 + + +def test_bessel(): + from sympy.functions.special.bessel import (besseli, besselj) + assert simplify(integrate(besselj(a, z)*besselj(b, z)/z, (z, 0, oo), + meijerg=True, conds='none')) == \ + 2*sin(pi*(a/2 - b/2))/(pi*(a - b)*(a + b)) + assert simplify(integrate(besselj(a, z)*besselj(a, z)/z, (z, 0, oo), + meijerg=True, conds='none')) == 1/(2*a) + + # TODO more orthogonality integrals + + assert simplify(integrate(sin(z*x)*(x**2 - 1)**(-(y + S.Half)), + (x, 1, oo), meijerg=True, conds='none') + *2/((z/2)**y*sqrt(pi)*gamma(S.Half - y))) == \ + besselj(y, z) + + # Werner Rosenheinrich + # SOME INDEFINITE INTEGRALS OF BESSEL FUNCTIONS + + assert integrate(x*besselj(0, x), x, meijerg=True) == x*besselj(1, x) + assert integrate(x*besseli(0, x), x, meijerg=True) == x*besseli(1, x) + # TODO can do higher powers, but come out as high order ... should they be + # reduced to order 0, 1? + assert integrate(besselj(1, x), x, meijerg=True) == -besselj(0, x) + assert integrate(besselj(1, x)**2/x, x, meijerg=True) == \ + -(besselj(0, x)**2 + besselj(1, x)**2)/2 + # TODO more besseli when tables are extended or recursive mellin works + assert integrate(besselj(0, x)**2/x**2, x, meijerg=True) == \ + -2*x*besselj(0, x)**2 - 2*x*besselj(1, x)**2 \ + + 2*besselj(0, x)*besselj(1, x) - besselj(0, x)**2/x + assert integrate(besselj(0, x)*besselj(1, x), x, meijerg=True) == \ + -besselj(0, x)**2/2 + assert integrate(x**2*besselj(0, x)*besselj(1, x), x, meijerg=True) == \ + x**2*besselj(1, x)**2/2 + assert integrate(besselj(0, x)*besselj(1, x)/x, x, meijerg=True) == \ + (x*besselj(0, x)**2 + x*besselj(1, x)**2 - + besselj(0, x)*besselj(1, x)) + # TODO how does besselj(0, a*x)*besselj(0, b*x) work? + # TODO how does besselj(0, x)**2*besselj(1, x)**2 work? + # TODO sin(x)*besselj(0, x) etc come out a mess + # TODO can x*log(x)*besselj(0, x) be done? + # TODO how does besselj(1, x)*besselj(0, x+a) work? + # TODO more indefinite integrals when struve functions etc are implemented + + # test a substitution + assert integrate(besselj(1, x**2)*x, x, meijerg=True) == \ + -besselj(0, x**2)/2 + + +def test_inversion(): + from sympy.functions.special.bessel import besselj + from sympy.functions.special.delta_functions import Heaviside + + def inv(f): + return piecewise_fold(meijerint_inversion(f, s, t)) + assert inv(1/(s**2 + 1)) == sin(t)*Heaviside(t) + assert inv(s/(s**2 + 1)) == cos(t)*Heaviside(t) + assert inv(exp(-s)/s) == Heaviside(t - 1) + assert inv(1/sqrt(1 + s**2)) == besselj(0, t)*Heaviside(t) + + # Test some antcedents checking. + assert meijerint_inversion(sqrt(s)/sqrt(1 + s**2), s, t) is None + assert inv(exp(s**2)) is None + assert meijerint_inversion(exp(-s**2), s, t) is None + + +def test_inversion_conditional_output(): + from sympy.core.symbol import Symbol + from sympy.integrals.transforms import InverseLaplaceTransform + + a = Symbol('a', positive=True) + F = sqrt(pi/a)*exp(-2*sqrt(a)*sqrt(s)) + f = meijerint_inversion(F, s, t) + assert not f.is_Piecewise + + b = Symbol('b', real=True) + F = F.subs(a, b) + f2 = meijerint_inversion(F, s, t) + assert f2.is_Piecewise + # first piece is same as f + assert f2.args[0][0] == f.subs(a, b) + # last piece is an unevaluated transform + assert f2.args[-1][1] + ILT = InverseLaplaceTransform(F, s, t, None) + assert f2.args[-1][0] == ILT or f2.args[-1][0] == ILT.as_integral + + +def test_inversion_exp_real_nonreal_shift(): + from sympy.core.symbol import Symbol + from sympy.functions.special.delta_functions import DiracDelta + r = Symbol('r', real=True) + c = Symbol('c', extended_real=False) + a = 1 + 2*I + z = Symbol('z') + assert not meijerint_inversion(exp(r*s), s, t).is_Piecewise + assert meijerint_inversion(exp(a*s), s, t) is None + assert meijerint_inversion(exp(c*s), s, t) is None + f = meijerint_inversion(exp(z*s), s, t) + assert f.is_Piecewise + assert isinstance(f.args[0][0], DiracDelta) + + +@slow +def test_lookup_table(): + from sympy.core.random import uniform, randrange + from sympy.core.add import Add + from sympy.integrals.meijerint import z as z_dummy + table = {} + _create_lookup_table(table) + for l in table.values(): + for formula, terms, cond, hint in sorted(l, key=default_sort_key): + subs = {} + for ai in list(formula.free_symbols) + [z_dummy]: + if hasattr(ai, 'properties') and ai.properties: + # these Wilds match positive integers + subs[ai] = randrange(1, 10) + else: + subs[ai] = uniform(1.5, 2.0) + if not isinstance(terms, list): + terms = terms(subs) + + # First test that hyperexpand can do this. + expanded = [hyperexpand(g) for (_, g) in terms] + assert all(x.is_Piecewise or not x.has(meijerg) for x in expanded) + + # Now test that the meijer g-function is indeed as advertised. + expanded = Add(*[f*x for (f, x) in terms]) + a, b = formula.n(subs=subs), expanded.n(subs=subs) + r = min(abs(a), abs(b)) + if r < 1: + assert abs(a - b).n() <= 1e-10 + else: + assert (abs(a - b)/r).n() <= 1e-10 + + +def test_branch_bug(): + from sympy.functions.special.gamma_functions import lowergamma + from sympy.simplify.powsimp import powdenest + # TODO gammasimp cannot prove that the factor is unity + assert powdenest(integrate(erf(x**3), x, meijerg=True).diff(x), + polar=True) == 2*erf(x**3)*gamma(Rational(2, 3))/3/gamma(Rational(5, 3)) + assert integrate(erf(x**3), x, meijerg=True) == \ + 2*x*erf(x**3)*gamma(Rational(2, 3))/(3*gamma(Rational(5, 3))) \ + - 2*gamma(Rational(2, 3))*lowergamma(Rational(2, 3), x**6)/(3*sqrt(pi)*gamma(Rational(5, 3))) + + +def test_linear_subs(): + from sympy.functions.special.bessel import besselj + assert integrate(sin(x - 1), x, meijerg=True) == -cos(1 - x) + assert integrate(besselj(1, x - 1), x, meijerg=True) == -besselj(0, 1 - x) + + +@slow +def test_probability(): + # various integrals from probability theory + from sympy.core.function import expand_mul + from sympy.core.symbol import (Symbol, symbols) + from sympy.simplify.gammasimp import gammasimp + from sympy.simplify.powsimp import powsimp + mu1, mu2 = symbols('mu1 mu2', nonzero=True) + sigma1, sigma2 = symbols('sigma1 sigma2', positive=True) + rate = Symbol('lambda', positive=True) + + def normal(x, mu, sigma): + return 1/sqrt(2*pi*sigma**2)*exp(-(x - mu)**2/2/sigma**2) + + def exponential(x, rate): + return rate*exp(-rate*x) + + assert integrate(normal(x, mu1, sigma1), (x, -oo, oo), meijerg=True) == 1 + assert integrate(x*normal(x, mu1, sigma1), (x, -oo, oo), meijerg=True) == \ + mu1 + assert integrate(x**2*normal(x, mu1, sigma1), (x, -oo, oo), meijerg=True) \ + == mu1**2 + sigma1**2 + assert integrate(x**3*normal(x, mu1, sigma1), (x, -oo, oo), meijerg=True) \ + == mu1**3 + 3*mu1*sigma1**2 + assert integrate(normal(x, mu1, sigma1)*normal(y, mu2, sigma2), + (x, -oo, oo), (y, -oo, oo), meijerg=True) == 1 + assert integrate(x*normal(x, mu1, sigma1)*normal(y, mu2, sigma2), + (x, -oo, oo), (y, -oo, oo), meijerg=True) == mu1 + assert integrate(y*normal(x, mu1, sigma1)*normal(y, mu2, sigma2), + (x, -oo, oo), (y, -oo, oo), meijerg=True) == mu2 + assert integrate(x*y*normal(x, mu1, sigma1)*normal(y, mu2, sigma2), + (x, -oo, oo), (y, -oo, oo), meijerg=True) == mu1*mu2 + assert integrate((x + y + 1)*normal(x, mu1, sigma1)*normal(y, mu2, sigma2), + (x, -oo, oo), (y, -oo, oo), meijerg=True) == 1 + mu1 + mu2 + assert integrate((x + y - 1)*normal(x, mu1, sigma1)*normal(y, mu2, sigma2), + (x, -oo, oo), (y, -oo, oo), meijerg=True) == \ + -1 + mu1 + mu2 + + i = integrate(x**2*normal(x, mu1, sigma1)*normal(y, mu2, sigma2), + (x, -oo, oo), (y, -oo, oo), meijerg=True) + assert not i.has(Abs) + assert simplify(i) == mu1**2 + sigma1**2 + assert integrate(y**2*normal(x, mu1, sigma1)*normal(y, mu2, sigma2), + (x, -oo, oo), (y, -oo, oo), meijerg=True) == \ + sigma2**2 + mu2**2 + + assert integrate(exponential(x, rate), (x, 0, oo), meijerg=True) == 1 + assert integrate(x*exponential(x, rate), (x, 0, oo), meijerg=True) == \ + 1/rate + assert integrate(x**2*exponential(x, rate), (x, 0, oo), meijerg=True) == \ + 2/rate**2 + + def E(expr): + res1 = integrate(expr*exponential(x, rate)*normal(y, mu1, sigma1), + (x, 0, oo), (y, -oo, oo), meijerg=True) + res2 = integrate(expr*exponential(x, rate)*normal(y, mu1, sigma1), + (y, -oo, oo), (x, 0, oo), meijerg=True) + assert expand_mul(res1) == expand_mul(res2) + return res1 + + assert E(1) == 1 + assert E(x*y) == mu1/rate + assert E(x*y**2) == mu1**2/rate + sigma1**2/rate + ans = sigma1**2 + 1/rate**2 + assert simplify(E((x + y + 1)**2) - E(x + y + 1)**2) == ans + assert simplify(E((x + y - 1)**2) - E(x + y - 1)**2) == ans + assert simplify(E((x + y)**2) - E(x + y)**2) == ans + + # Beta' distribution + alpha, beta = symbols('alpha beta', positive=True) + betadist = x**(alpha - 1)*(1 + x)**(-alpha - beta)*gamma(alpha + beta) \ + /gamma(alpha)/gamma(beta) + assert integrate(betadist, (x, 0, oo), meijerg=True) == 1 + i = integrate(x*betadist, (x, 0, oo), meijerg=True, conds='separate') + assert (gammasimp(i[0]), i[1]) == (alpha/(beta - 1), 1 < beta) + j = integrate(x**2*betadist, (x, 0, oo), meijerg=True, conds='separate') + assert j[1] == (beta > 2) + assert gammasimp(j[0] - i[0]**2) == (alpha + beta - 1)*alpha \ + /(beta - 2)/(beta - 1)**2 + + # Beta distribution + # NOTE: this is evaluated using antiderivatives. It also tests that + # meijerint_indefinite returns the simplest possible answer. + a, b = symbols('a b', positive=True) + betadist = x**(a - 1)*(-x + 1)**(b - 1)*gamma(a + b)/(gamma(a)*gamma(b)) + assert simplify(integrate(betadist, (x, 0, 1), meijerg=True)) == 1 + assert simplify(integrate(x*betadist, (x, 0, 1), meijerg=True)) == \ + a/(a + b) + assert simplify(integrate(x**2*betadist, (x, 0, 1), meijerg=True)) == \ + a*(a + 1)/(a + b)/(a + b + 1) + assert simplify(integrate(x**y*betadist, (x, 0, 1), meijerg=True)) == \ + gamma(a + b)*gamma(a + y)/gamma(a)/gamma(a + b + y) + + # Chi distribution + k = Symbol('k', integer=True, positive=True) + chi = 2**(1 - k/2)*x**(k - 1)*exp(-x**2/2)/gamma(k/2) + assert powsimp(integrate(chi, (x, 0, oo), meijerg=True)) == 1 + assert simplify(integrate(x*chi, (x, 0, oo), meijerg=True)) == \ + sqrt(2)*gamma((k + 1)/2)/gamma(k/2) + assert simplify(integrate(x**2*chi, (x, 0, oo), meijerg=True)) == k + + # Chi^2 distribution + chisquared = 2**(-k/2)/gamma(k/2)*x**(k/2 - 1)*exp(-x/2) + assert powsimp(integrate(chisquared, (x, 0, oo), meijerg=True)) == 1 + assert simplify(integrate(x*chisquared, (x, 0, oo), meijerg=True)) == k + assert simplify(integrate(x**2*chisquared, (x, 0, oo), meijerg=True)) == \ + k*(k + 2) + assert gammasimp(integrate(((x - k)/sqrt(2*k))**3*chisquared, (x, 0, oo), + meijerg=True)) == 2*sqrt(2)/sqrt(k) + + # Dagum distribution + a, b, p = symbols('a b p', positive=True) + # XXX (x/b)**a does not work + dagum = a*p/x*(x/b)**(a*p)/(1 + x**a/b**a)**(p + 1) + assert simplify(integrate(dagum, (x, 0, oo), meijerg=True)) == 1 + # XXX conditions are a mess + arg = x*dagum + assert simplify(integrate(arg, (x, 0, oo), meijerg=True, conds='none') + ) == a*b*gamma(1 - 1/a)*gamma(p + 1 + 1/a)/( + (a*p + 1)*gamma(p)) + assert simplify(integrate(x*arg, (x, 0, oo), meijerg=True, conds='none') + ) == a*b**2*gamma(1 - 2/a)*gamma(p + 1 + 2/a)/( + (a*p + 2)*gamma(p)) + + # F-distribution + d1, d2 = symbols('d1 d2', positive=True) + f = sqrt(((d1*x)**d1 * d2**d2)/(d1*x + d2)**(d1 + d2))/x \ + /gamma(d1/2)/gamma(d2/2)*gamma((d1 + d2)/2) + assert simplify(integrate(f, (x, 0, oo), meijerg=True)) == 1 + # TODO conditions are a mess + assert simplify(integrate(x*f, (x, 0, oo), meijerg=True, conds='none') + ) == d2/(d2 - 2) + assert simplify(integrate(x**2*f, (x, 0, oo), meijerg=True, conds='none') + ) == d2**2*(d1 + 2)/d1/(d2 - 4)/(d2 - 2) + + # TODO gamma, rayleigh + + # inverse gaussian + lamda, mu = symbols('lamda mu', positive=True) + dist = sqrt(lamda/2/pi)*x**(Rational(-3, 2))*exp(-lamda*(x - mu)**2/x/2/mu**2) + mysimp = lambda expr: simplify(expr.rewrite(exp)) + assert mysimp(integrate(dist, (x, 0, oo))) == 1 + assert mysimp(integrate(x*dist, (x, 0, oo))) == mu + assert mysimp(integrate((x - mu)**2*dist, (x, 0, oo))) == mu**3/lamda + assert mysimp(integrate((x - mu)**3*dist, (x, 0, oo))) == 3*mu**5/lamda**2 + + # Levi + c = Symbol('c', positive=True) + assert integrate(sqrt(c/2/pi)*exp(-c/2/(x - mu))/(x - mu)**S('3/2'), + (x, mu, oo)) == 1 + # higher moments oo + + # log-logistic + alpha, beta = symbols('alpha beta', positive=True) + distn = (beta/alpha)*x**(beta - 1)/alpha**(beta - 1)/ \ + (1 + x**beta/alpha**beta)**2 + # FIXME: If alpha, beta are not declared as finite the line below hangs + # after the changes in: + # https://github.com/sympy/sympy/pull/16603 + assert simplify(integrate(distn, (x, 0, oo))) == 1 + # NOTE the conditions are a mess, but correctly state beta > 1 + assert simplify(integrate(x*distn, (x, 0, oo), conds='none')) == \ + pi*alpha/beta/sin(pi/beta) + # (similar comment for conditions applies) + assert simplify(integrate(x**y*distn, (x, 0, oo), conds='none')) == \ + pi*alpha**y*y/beta/sin(pi*y/beta) + + # weibull + k = Symbol('k', positive=True) + n = Symbol('n', positive=True) + distn = k/lamda*(x/lamda)**(k - 1)*exp(-(x/lamda)**k) + assert simplify(integrate(distn, (x, 0, oo))) == 1 + assert simplify(integrate(x**n*distn, (x, 0, oo))) == \ + lamda**n*gamma(1 + n/k) + + # rice distribution + from sympy.functions.special.bessel import besseli + nu, sigma = symbols('nu sigma', positive=True) + rice = x/sigma**2*exp(-(x**2 + nu**2)/2/sigma**2)*besseli(0, x*nu/sigma**2) + assert integrate(rice, (x, 0, oo), meijerg=True) == 1 + # can someone verify higher moments? + + # Laplace distribution + mu = Symbol('mu', real=True) + b = Symbol('b', positive=True) + laplace = exp(-abs(x - mu)/b)/2/b + assert integrate(laplace, (x, -oo, oo), meijerg=True) == 1 + assert integrate(x*laplace, (x, -oo, oo), meijerg=True) == mu + assert integrate(x**2*laplace, (x, -oo, oo), meijerg=True) == \ + 2*b**2 + mu**2 + + # TODO are there other distributions supported on (-oo, oo) that we can do? + + # misc tests + k = Symbol('k', positive=True) + assert gammasimp(expand_mul(integrate(log(x)*x**(k - 1)*exp(-x)/gamma(k), + (x, 0, oo)))) == polygamma(0, k) + + +@slow +def test_expint(): + """ Test various exponential integrals. """ + from sympy.core.symbol import Symbol + from sympy.functions.elementary.hyperbolic import sinh + from sympy.functions.special.error_functions import (Chi, Ci, Ei, Shi, Si, expint) + assert simplify(unpolarify(integrate(exp(-z*x)/x**y, (x, 1, oo), + meijerg=True, conds='none' + ).rewrite(expint).expand(func=True))) == expint(y, z) + + assert integrate(exp(-z*x)/x, (x, 1, oo), meijerg=True, + conds='none').rewrite(expint).expand() == \ + expint(1, z) + assert integrate(exp(-z*x)/x**2, (x, 1, oo), meijerg=True, + conds='none').rewrite(expint).expand() == \ + expint(2, z).rewrite(Ei).rewrite(expint) + assert integrate(exp(-z*x)/x**3, (x, 1, oo), meijerg=True, + conds='none').rewrite(expint).expand() == \ + expint(3, z).rewrite(Ei).rewrite(expint).expand() + + t = Symbol('t', positive=True) + assert integrate(-cos(x)/x, (x, t, oo), meijerg=True).expand() == Ci(t) + assert integrate(-sin(x)/x, (x, t, oo), meijerg=True).expand() == \ + Si(t) - pi/2 + assert integrate(sin(x)/x, (x, 0, z), meijerg=True) == Si(z) + assert integrate(sinh(x)/x, (x, 0, z), meijerg=True) == Shi(z) + assert integrate(exp(-x)/x, x, meijerg=True).expand().rewrite(expint) == \ + I*pi - expint(1, x) + assert integrate(exp(-x)/x**2, x, meijerg=True).rewrite(expint).expand() \ + == expint(1, x) - exp(-x)/x - I*pi + + u = Symbol('u', polar=True) + assert integrate(cos(u)/u, u, meijerg=True).expand().as_independent(u)[1] \ + == Ci(u) + assert integrate(cosh(u)/u, u, meijerg=True).expand().as_independent(u)[1] \ + == Chi(u) + + assert integrate(expint(1, x), x, meijerg=True + ).rewrite(expint).expand() == x*expint(1, x) - exp(-x) + assert integrate(expint(2, x), x, meijerg=True + ).rewrite(expint).expand() == \ + -x**2*expint(1, x)/2 + x*exp(-x)/2 - exp(-x)/2 + assert simplify(unpolarify(integrate(expint(y, x), x, + meijerg=True).rewrite(expint).expand(func=True))) == \ + -expint(y + 1, x) + + assert integrate(Si(x), x, meijerg=True) == x*Si(x) + cos(x) + assert integrate(Ci(u), u, meijerg=True).expand() == u*Ci(u) - sin(u) + assert integrate(Shi(x), x, meijerg=True) == x*Shi(x) - cosh(x) + assert integrate(Chi(u), u, meijerg=True).expand() == u*Chi(u) - sinh(u) + + assert integrate(Si(x)*exp(-x), (x, 0, oo), meijerg=True) == pi/4 + assert integrate(expint(1, x)*sin(x), (x, 0, oo), meijerg=True) == log(2)/2 + + +def test_messy(): + from sympy.functions.elementary.hyperbolic import (acosh, acoth) + from sympy.functions.elementary.trigonometric import (asin, atan) + from sympy.functions.special.bessel import besselj + from sympy.functions.special.error_functions import (Chi, E1, Shi, Si) + from sympy.integrals.transforms import (fourier_transform, laplace_transform) + assert (laplace_transform(Si(x), x, s, simplify=True) == + ((-atan(s) + pi/2)/s, 0, True)) + + assert laplace_transform(Shi(x), x, s, simplify=True) == ( + acoth(s)/s, -oo, s**2 > 1) + + # where should the logs be simplified? + assert laplace_transform(Chi(x), x, s, simplify=True) == ( + (log(s**(-2)) - log(1 - 1/s**2))/(2*s), -oo, s**2 > 1) + + # TODO maybe simplify the inequalities? when the simplification + # allows for generators instead of symbols this will work + assert laplace_transform(besselj(a, x), x, s)[1:] == \ + (0, (re(a) > -2) & (re(a) > -1)) + + # NOTE s < 0 can be done, but argument reduction is not good enough yet + ans = fourier_transform(besselj(1, x)/x, x, s, noconds=False) + assert (ans[0].factor(deep=True).expand(), ans[1]) == \ + (Piecewise((0, (s > 1/(2*pi)) | (s < -1/(2*pi))), + (2*sqrt(-4*pi**2*s**2 + 1), True)), s > 0) + # TODO FT(besselj(0,x)) - conditions are messy (but for acceptable reasons) + # - folding could be better + + assert integrate(E1(x)*besselj(0, x), (x, 0, oo), meijerg=True) == \ + log(1 + sqrt(2)) + assert integrate(E1(x)*besselj(1, x), (x, 0, oo), meijerg=True) == \ + log(S.Half + sqrt(2)/2) + + assert integrate(1/x/sqrt(1 - x**2), x, meijerg=True) == \ + Piecewise((-acosh(1/x), abs(x**(-2)) > 1), (I*asin(1/x), True)) + + +def test_issue_6122(): + assert integrate(exp(-I*x**2), (x, -oo, oo), meijerg=True) == \ + -I*sqrt(pi)*exp(I*pi/4) + + +def test_issue_6252(): + expr = 1/x/(a + b*x)**Rational(1, 3) + anti = integrate(expr, x, meijerg=True) + assert not anti.has(hyper) + # XXX the expression is a mess, but actually upon differentiation and + # putting in numerical values seems to work... + + +def test_issue_6348(): + assert integrate(exp(I*x)/(1 + x**2), (x, -oo, oo)).simplify().rewrite(exp) \ + == pi*exp(-1) + + +def test_fresnel(): + from sympy.functions.special.error_functions import (fresnelc, fresnels) + + assert expand_func(integrate(sin(pi*x**2/2), x)) == fresnels(x) + assert expand_func(integrate(cos(pi*x**2/2), x)) == fresnelc(x) + + +def test_issue_6860(): + assert meijerint_indefinite(x**x**x, x) is None + + +def test_issue_7337(): + f = meijerint_indefinite(x*sqrt(2*x + 3), x).together() + assert f == sqrt(2*x + 3)*(2*x**2 + x - 3)/5 + assert f._eval_interval(x, S.NegativeOne, S.One) == Rational(2, 5) + + +def test_issue_8368(): + assert meijerint_indefinite(cosh(x)*exp(-x*t), x) == ( + (-t - 1)*exp(x) + (-t + 1)*exp(-x))*exp(-t*x)/2/(t**2 - 1) + + +def test_issue_10211(): + from sympy.abc import h, w + assert integrate((1/sqrt((y-x)**2 + h**2)**3), (x,0,w), (y,0,w)) == \ + 2*sqrt(1 + w**2/h**2)/h - 2/h + + +def test_issue_11806(): + from sympy.core.symbol import symbols + y, L = symbols('y L', positive=True) + assert integrate(1/sqrt(x**2 + y**2)**3, (x, -L, L)) == \ + 2*L/(y**2*sqrt(L**2 + y**2)) + +def test_issue_10681(): + from sympy.polys.domains.realfield import RR + from sympy.abc import R, r + f = integrate(r**2*(R**2-r**2)**0.5, r, meijerg=True) + g = (1.0/3)*R**1.0*r**3*hyper((-0.5, Rational(3, 2)), (Rational(5, 2),), + r**2*exp_polar(2*I*pi)/R**2) + assert RR.almosteq((f/g).n(), 1.0, 1e-12) + +def test_issue_13536(): + from sympy.core.symbol import Symbol + a = Symbol('a', positive=True) + assert integrate(1/x**2, (x, oo, a)) == -1/a + + +def test_issue_6462(): + from sympy.core.symbol import Symbol + x = Symbol('x') + n = Symbol('n') + # Not the actual issue, still wrong answer for n = 1, but that there is no + # exception + assert integrate(cos(x**n)/x**n, x, meijerg=True).subs(n, 2).equals( + integrate(cos(x**2)/x**2, x, meijerg=True)) + + +def test_indefinite_1_bug(): + assert integrate((b + t)**(-a), t, meijerg=True) == -b*(1 + t/b)**(1 - a)/(a*b**a - b**a) + + +def test_pr_23583(): + # This result is wrong. Check whether new result is correct when this test fail. + assert integrate(1/sqrt((x - I)**2-1), meijerg=True) == \ + Piecewise((acosh(x - I), Abs((x - I)**2) > 1), (-I*asin(x - I), True)) + + +# 25786 +def test_integrate_function_of_square_over_negatives(): + assert integrate(exp(-x**2), (x,-5,0), meijerg=True) == sqrt(pi)/2 * erf(5) + + +def test_issue_25949(): + from sympy.core.symbol import symbols + y = symbols("y", nonzero=True) + assert integrate(cosh(y*(x + 1)), (x, -1, -0.25), meijerg=True) == sinh(0.75*y)/y diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_prde.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_prde.py new file mode 100644 index 0000000000000000000000000000000000000000..a7429ea8634c742eb77cdb26f99b2cb15853cd42 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_prde.py @@ -0,0 +1,322 @@ +"""Most of these tests come from the examples in Bronstein's book.""" +from sympy.integrals.risch import DifferentialExtension, derivation +from sympy.integrals.prde import (prde_normal_denom, prde_special_denom, + prde_linear_constraints, constant_system, prde_spde, prde_no_cancel_b_large, + prde_no_cancel_b_small, limited_integrate_reduce, limited_integrate, + is_deriv_k, is_log_deriv_k_t_radical, parametric_log_deriv_heu, + is_log_deriv_k_t_radical_in_field, param_poly_rischDE, param_rischDE, + prde_cancel_liouvillian) + +from sympy.polys.polymatrix import PolyMatrix as Matrix + +from sympy.core.numbers import Rational +from sympy.core.singleton import S +from sympy.core.symbol import symbols +from sympy.polys.domains.rationalfield import QQ +from sympy.polys.polytools import Poly +from sympy.abc import x, t, n + +t0, t1, t2, t3, k = symbols('t:4 k') + + +def test_prde_normal_denom(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t**2, t)]}) + fa = Poly(1, t) + fd = Poly(x, t) + G = [(Poly(t, t), Poly(1 + t**2, t)), (Poly(1, t), Poly(x + x*t**2, t))] + assert prde_normal_denom(fa, fd, G, DE) == \ + (Poly(x, t, domain='ZZ(x)'), (Poly(1, t, domain='ZZ(x)'), Poly(1, t, + domain='ZZ(x)')), [(Poly(x*t, t, domain='ZZ(x)'), + Poly(t**2 + 1, t, domain='ZZ(x)')), (Poly(1, t, domain='ZZ(x)'), + Poly(t**2 + 1, t, domain='ZZ(x)'))], Poly(1, t, domain='ZZ(x)')) + G = [(Poly(t, t), Poly(t**2 + 2*t + 1, t)), (Poly(x*t, t), + Poly(t**2 + 2*t + 1, t)), (Poly(x*t**2, t), Poly(t**2 + 2*t + 1, t))] + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert prde_normal_denom(Poly(x, t), Poly(1, t), G, DE) == \ + (Poly(t + 1, t), (Poly((-1 + x)*t + x, t), Poly(1, t, domain='ZZ[x]')), [(Poly(t, t), + Poly(1, t)), (Poly(x*t, t), Poly(1, t, domain='ZZ[x]')), (Poly(x*t**2, t), + Poly(1, t, domain='ZZ[x]'))], Poly(t + 1, t)) + + +def test_prde_special_denom(): + a = Poly(t + 1, t) + ba = Poly(t**2, t) + bd = Poly(1, t) + G = [(Poly(t, t), Poly(1, t)), (Poly(t**2, t), Poly(1, t)), (Poly(t**3, t), Poly(1, t))] + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert prde_special_denom(a, ba, bd, G, DE) == \ + (Poly(t + 1, t), Poly(t**2, t), [(Poly(t, t), Poly(1, t)), + (Poly(t**2, t), Poly(1, t)), (Poly(t**3, t), Poly(1, t))], Poly(1, t)) + G = [(Poly(t, t), Poly(1, t)), (Poly(1, t), Poly(t, t))] + assert prde_special_denom(Poly(1, t), Poly(t**2, t), Poly(1, t), G, DE) == \ + (Poly(1, t), Poly(t**2 - 1, t), [(Poly(t**2, t), Poly(1, t)), + (Poly(1, t), Poly(1, t))], Poly(t, t)) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-2*x*t0, t0)]}) + DE.decrement_level() + G = [(Poly(t, t), Poly(t**2, t)), (Poly(2*t, t), Poly(t, t))] + assert prde_special_denom(Poly(5*x*t + 1, t), Poly(t**2 + 2*x**3*t, t), Poly(t**3 + 2, t), G, DE) == \ + (Poly(5*x*t + 1, t), Poly(0, t, domain='ZZ[x]'), [(Poly(t, t), Poly(t**2, t)), + (Poly(2*t, t), Poly(t, t))], Poly(1, x)) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly((t**2 + 1)*2*x, t)]}) + G = [(Poly(t + x, t), Poly(t*x, t)), (Poly(2*t, t), Poly(x**2, x))] + assert prde_special_denom(Poly(5*x*t + 1, t), Poly(t**2 + 2*x**3*t, t), Poly(t**3, t), G, DE) == \ + (Poly(5*x*t + 1, t), Poly(0, t, domain='ZZ[x]'), [(Poly(t + x, t), Poly(x*t, t)), + (Poly(2*t, t, x), Poly(x**2, t, x))], Poly(1, t)) + assert prde_special_denom(Poly(t + 1, t), Poly(t**2, t), Poly(t**3, t), G, DE) == \ + (Poly(t + 1, t), Poly(0, t, domain='ZZ[x]'), [(Poly(t + x, t), Poly(x*t, t)), (Poly(2*t, t, x), + Poly(x**2, t, x))], Poly(1, t)) + + +def test_prde_linear_constraints(): + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + G = [(Poly(2*x**3 + 3*x + 1, x), Poly(x**2 - 1, x)), (Poly(1, x), Poly(x - 1, x)), + (Poly(1, x), Poly(x + 1, x))] + assert prde_linear_constraints(Poly(1, x), Poly(0, x), G, DE) == \ + ((Poly(2*x, x, domain='QQ'), Poly(0, x, domain='QQ'), Poly(0, x, domain='QQ')), + Matrix([[1, 1, -1], [5, 1, 1]], x)) + G = [(Poly(t, t), Poly(1, t)), (Poly(t**2, t), Poly(1, t)), (Poly(t**3, t), Poly(1, t))] + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert prde_linear_constraints(Poly(t + 1, t), Poly(t**2, t), G, DE) == \ + ((Poly(t, t, domain='QQ'), Poly(t**2, t, domain='QQ'), Poly(t**3, t, domain='QQ')), + Matrix(0, 3, [], t)) + G = [(Poly(2*x, t), Poly(t, t)), (Poly(-x, t), Poly(t, t))] + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + assert prde_linear_constraints(Poly(1, t), Poly(0, t), G, DE) == \ + ((Poly(0, t, domain='QQ[x]'), Poly(0, t, domain='QQ[x]')), Matrix([[2*x, -x]], t)) + + +def test_constant_system(): + A = Matrix([[-(x + 3)/(x - 1), (x + 1)/(x - 1), 1], + [-x - 3, x + 1, x - 1], + [2*(x + 3)/(x - 1), 0, 0]], t) + u = Matrix([[(x + 1)/(x - 1)], [x + 1], [0]], t) + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + R = QQ.frac_field(x)[t] + assert constant_system(A, u, DE) == \ + (Matrix([[1, 0, 0], + [0, 1, 0], + [0, 0, 0], + [0, 0, 1]], ring=R), Matrix([0, 1, 0, 0], ring=R)) + + +def test_prde_spde(): + D = [Poly(x, t), Poly(-x*t, t)] + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + # TODO: when bound_degree() can handle this, test degree bound from that too + assert prde_spde(Poly(t, t), Poly(-1/x, t), D, n, DE) == \ + (Poly(t, t), Poly(0, t, domain='ZZ(x)'), + [Poly(2*x, t, domain='ZZ(x)'), Poly(-x, t, domain='ZZ(x)')], + [Poly(-x**2, t, domain='ZZ(x)'), Poly(0, t, domain='ZZ(x)')], n - 1) + + +def test_prde_no_cancel(): + # b large + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + assert prde_no_cancel_b_large(Poly(1, x), [Poly(x**2, x), Poly(1, x)], 2, DE) == \ + ([Poly(x**2 - 2*x + 2, x), Poly(1, x)], Matrix([[1, 0, -1, 0], + [0, 1, 0, -1]], x)) + assert prde_no_cancel_b_large(Poly(1, x), [Poly(x**3, x), Poly(1, x)], 3, DE) == \ + ([Poly(x**3 - 3*x**2 + 6*x - 6, x), Poly(1, x)], Matrix([[1, 0, -1, 0], + [0, 1, 0, -1]], x)) + assert prde_no_cancel_b_large(Poly(x, x), [Poly(x**2, x), Poly(1, x)], 1, DE) == \ + ([Poly(x, x, domain='ZZ'), Poly(0, x, domain='ZZ')], Matrix([[1, -1, 0, 0], + [1, 0, -1, 0], + [0, 1, 0, -1]], x)) + # b small + # XXX: Is there a better example of a monomial with D.degree() > 2? + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**3 + 1, t)]}) + + # My original q was t**4 + t + 1, but this solution implies q == t**4 + # (c1 = 4), with some of the ci for the original q equal to 0. + G = [Poly(t**6, t), Poly(x*t**5, t), Poly(t**3, t), Poly(x*t**2, t), Poly(1 + x, t)] + R = QQ.frac_field(x)[t] + assert prde_no_cancel_b_small(Poly(x*t, t), G, 4, DE) == \ + ([Poly(t**4/4 - x/12*t**3 + x**2/24*t**2 + (Rational(-11, 12) - x**3/24)*t + x/24, t), + Poly(x/3*t**3 - x**2/6*t**2 + (Rational(-1, 3) + x**3/6)*t - x/6, t), Poly(t, t), + Poly(0, t), Poly(0, t)], Matrix([[1, 0, -1, 0, 0, 0, 0, 0, 0, 0], + [0, 1, Rational(-1, 4), 0, 0, 0, 0, 0, 0, 0], + [0, 0, 0, 0, 0, 0, 0, 0, 0, 0], + [0, 0, 0, 1, 0, 0, 0, 0, 0, 0], + [0, 0, 0, 0, 1, 0, 0, 0, 0, 0], + [1, 0, 0, 0, 0, -1, 0, 0, 0, 0], + [0, 1, 0, 0, 0, 0, -1, 0, 0, 0], + [0, 0, 1, 0, 0, 0, 0, -1, 0, 0], + [0, 0, 0, 1, 0, 0, 0, 0, -1, 0], + [0, 0, 0, 0, 1, 0, 0, 0, 0, -1]], ring=R)) + + # TODO: Add test for deg(b) <= 0 with b small + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t**2, t)]}) + b = Poly(-1/x**2, t, field=True) # deg(b) == 0 + q = [Poly(x**i*t**j, t, field=True) for i in range(2) for j in range(3)] + h, A = prde_no_cancel_b_small(b, q, 3, DE) + V = A.nullspace() + R = QQ.frac_field(x)[t] + assert len(V) == 1 + assert V[0] == Matrix([Rational(-1, 2), 0, 0, 1, 0, 0]*3, ring=R) + assert (Matrix([h])*V[0][6:, :])[0] == Poly(x**2/2, t, domain='QQ(x)') + assert (Matrix([q])*V[0][:6, :])[0] == Poly(x - S.Half, t, domain='QQ(x)') + + +def test_prde_cancel_liouvillian(): + ### 1. case == 'primitive' + # used when integrating f = log(x) - log(x - 1) + # Not taken from 'the' book + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + p0 = Poly(0, t, field=True) + p1 = Poly((x - 1)*t, t, domain='ZZ(x)') + p2 = Poly(x - 1, t, domain='ZZ(x)') + p3 = Poly(-x**2 + x, t, domain='ZZ(x)') + h, A = prde_cancel_liouvillian(Poly(-1/(x - 1), t), [Poly(-x + 1, t), Poly(1, t)], 1, DE) + V = A.nullspace() + assert h == [p0, p0, p1, p0, p0, p0, p0, p0, p0, p0, p2, p3, p0, p0, p0, p0] + assert A.rank() == 16 + assert (Matrix([h])*V[0][:16, :]) == Matrix([[Poly(0, t, domain='QQ(x)')]]) + + ### 2. case == 'exp' + # used when integrating log(x/exp(x) + 1) + # Not taken from book + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-t, t)]}) + assert prde_cancel_liouvillian(Poly(0, t, domain='QQ[x]'), [Poly(1, t, domain='QQ(x)')], 0, DE) == \ + ([Poly(1, t, domain='QQ'), Poly(x, t, domain='ZZ(x)')], Matrix([[-1, 0, 1]], DE.t)) + + +def test_param_poly_rischDE(): + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + a = Poly(x**2 - x, x, field=True) + b = Poly(1, x, field=True) + q = [Poly(x, x, field=True), Poly(x**2, x, field=True)] + h, A = param_poly_rischDE(a, b, q, 3, DE) + + assert A.nullspace() == [Matrix([0, 1, 1, 1], DE.t)] # c1, c2, d1, d2 + # Solution of a*Dp + b*p = c1*q1 + c2*q2 = q2 = x**2 + # is d1*h1 + d2*h2 = h1 + h2 = x. + assert h[0] + h[1] == Poly(x, x, domain='QQ') + # a*Dp + b*p = q1 = x has no solution. + + a = Poly(x**2 - x, x, field=True) + b = Poly(x**2 - 5*x + 3, x, field=True) + q = [Poly(1, x, field=True), Poly(x, x, field=True), + Poly(x**2, x, field=True)] + h, A = param_poly_rischDE(a, b, q, 3, DE) + + assert A.nullspace() == [Matrix([3, -5, 1, -5, 1, 1], DE.t)] + p = -Poly(5, DE.t)*h[0] + h[1] + h[2] # Poly(1, x) + assert a*derivation(p, DE) + b*p == Poly(x**2 - 5*x + 3, x, domain='QQ') + + +def test_param_rischDE(): + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + p1, px = Poly(1, x, field=True), Poly(x, x, field=True) + G = [(p1, px), (p1, p1), (px, p1)] # [1/x, 1, x] + h, A = param_rischDE(-p1, Poly(x**2, x, field=True), G, DE) + assert len(h) == 3 + p = [hi[0].as_expr()/hi[1].as_expr() for hi in h] + V = A.nullspace() + assert len(V) == 2 + assert V[0] == Matrix([-1, 1, 0, -1, 1, 0], DE.t) + y = -p[0] + p[1] + 0*p[2] # x + assert y.diff(x) - y/x**2 == 1 - 1/x # Dy + f*y == -G0 + G1 + 0*G2 + + # the below test computation takes place while computing the integral + # of 'f = log(log(x + exp(x)))' + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + G = [(Poly(t + x, t, domain='ZZ(x)'), Poly(1, t, domain='QQ')), (Poly(0, t, domain='QQ'), Poly(1, t, domain='QQ'))] + h, A = param_rischDE(Poly(-t - 1, t, field=True), Poly(t + x, t, field=True), G, DE) + assert len(h) == 5 + p = [hi[0].as_expr()/hi[1].as_expr() for hi in h] + V = A.nullspace() + assert len(V) == 3 + assert V[0] == Matrix([0, 0, 0, 0, 1, 0, 0], DE.t) + y = 0*p[0] + 0*p[1] + 1*p[2] + 0*p[3] + 0*p[4] + assert y.diff(t) - y/(t + x) == 0 # Dy + f*y = 0*G0 + 0*G1 + + +def test_limited_integrate_reduce(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + assert limited_integrate_reduce(Poly(x, t), Poly(t**2, t), [(Poly(x, t), + Poly(t, t))], DE) == \ + (Poly(t, t), Poly(-1/x, t), Poly(t, t), 1, (Poly(x, t), Poly(1, t, domain='ZZ[x]')), + [(Poly(-x*t, t), Poly(1, t, domain='ZZ[x]'))]) + + +def test_limited_integrate(): + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + G = [(Poly(x, x), Poly(x + 1, x))] + assert limited_integrate(Poly(-(1 + x + 5*x**2 - 3*x**3), x), + Poly(1 - x - x**2 + x**3, x), G, DE) == \ + ((Poly(x**2 - x + 2, x), Poly(x - 1, x, domain='QQ')), [2]) + G = [(Poly(1, x), Poly(x, x))] + assert limited_integrate(Poly(5*x**2, x), Poly(3, x), G, DE) == \ + ((Poly(5*x**3/9, x), Poly(1, x, domain='QQ')), [0]) + + +def test_is_log_deriv_k_t_radical(): + DE = DifferentialExtension(extension={'D': [Poly(1, x)], 'exts': [None], + 'extargs': [None]}) + assert is_log_deriv_k_t_radical(Poly(2*x, x), Poly(1, x), DE) is None + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(2*t1, t1), Poly(1/x, t2)], + 'exts': [None, 'exp', 'log'], 'extargs': [None, 2*x, x]}) + assert is_log_deriv_k_t_radical(Poly(x + t2/2, t2), Poly(1, t2), DE) == \ + ([(t1, 1), (x, 1)], t1*x, 2, 0) + # TODO: Add more tests + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t0, t0), Poly(1/x, t)], + 'exts': [None, 'exp', 'log'], 'extargs': [None, x, x]}) + assert is_log_deriv_k_t_radical(Poly(x + t/2 + 3, t), Poly(1, t), DE) == \ + ([(t0, 2), (x, 1)], x*t0**2, 2, 3) + + +def test_is_deriv_k(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t1), Poly(1/(x + 1), t2)], + 'exts': [None, 'log', 'log'], 'extargs': [None, x, x + 1]}) + assert is_deriv_k(Poly(2*x**2 + 2*x, t2), Poly(1, t2), DE) == \ + ([(t1, 1), (t2, 1)], t1 + t2, 2) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t1), Poly(t2, t2)], + 'exts': [None, 'log', 'exp'], 'extargs': [None, x, x]}) + assert is_deriv_k(Poly(x**2*t2**3, t2), Poly(1, t2), DE) == \ + ([(x, 3), (t1, 2)], 2*t1 + 3*x, 1) + # TODO: Add more tests, including ones with exponentials + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(2/x, t1)], + 'exts': [None, 'log'], 'extargs': [None, x**2]}) + assert is_deriv_k(Poly(x, t1), Poly(1, t1), DE) == \ + ([(t1, S.Half)], t1/2, 1) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(2/(1 + x), t0)], + 'exts': [None, 'log'], 'extargs': [None, x**2 + 2*x + 1]}) + assert is_deriv_k(Poly(1 + x, t0), Poly(1, t0), DE) == \ + ([(t0, S.Half)], t0/2, 1) + + # Issue 10798 + # DE = DifferentialExtension(log(1/x), x) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-1/x, t)], + 'exts': [None, 'log'], 'extargs': [None, 1/x]}) + assert is_deriv_k(Poly(1, t), Poly(x, t), DE) == ([(t, 1)], t, 1) + + +def test_is_log_deriv_k_t_radical_in_field(): + # NOTE: any potential constant factor in the second element of the result + # doesn't matter, because it cancels in Da/a. + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + assert is_log_deriv_k_t_radical_in_field(Poly(5*t + 1, t), Poly(2*t*x, t), DE) == \ + (2, t*x**5) + assert is_log_deriv_k_t_radical_in_field(Poly(2 + 3*t, t), Poly(5*x*t, t), DE) == \ + (5, x**3*t**2) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-t/x**2, t)]}) + assert is_log_deriv_k_t_radical_in_field(Poly(-(1 + 2*t), t), + Poly(2*x**2 + 2*x**2*t, t), DE) == \ + (2, t + t**2) + assert is_log_deriv_k_t_radical_in_field(Poly(-1, t), Poly(x**2, t), DE) == \ + (1, t) + assert is_log_deriv_k_t_radical_in_field(Poly(1, t), Poly(2*x**2, t), DE) == \ + (2, 1/t) + + +def test_parametric_log_deriv(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + assert parametric_log_deriv_heu(Poly(5*t**2 + t - 6, t), Poly(2*x*t**2, t), + Poly(-1, t), Poly(x*t**2, t), DE) == \ + (2, 6, t*x**5) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_quadrature.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_quadrature.py new file mode 100644 index 0000000000000000000000000000000000000000..97471dbdbc13fda0bce7a8823ff2cefac4ab8802 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_quadrature.py @@ -0,0 +1,601 @@ +from sympy.core import S, Rational +from sympy.integrals.quadrature import (gauss_legendre, gauss_laguerre, + gauss_hermite, gauss_gen_laguerre, + gauss_chebyshev_t, gauss_chebyshev_u, + gauss_jacobi, gauss_lobatto) + + +def test_legendre(): + x, w = gauss_legendre(1, 17) + assert [str(r) for r in x] == ['0'] + assert [str(r) for r in w] == ['2.0000000000000000'] + + x, w = gauss_legendre(2, 17) + assert [str(r) for r in x] == [ + '-0.57735026918962576', + '0.57735026918962576'] + assert [str(r) for r in w] == [ + '1.0000000000000000', + '1.0000000000000000'] + + x, w = gauss_legendre(3, 17) + assert [str(r) for r in x] == [ + '-0.77459666924148338', + '0', + '0.77459666924148338'] + assert [str(r) for r in w] == [ + '0.55555555555555556', + '0.88888888888888889', + '0.55555555555555556'] + + x, w = gauss_legendre(4, 17) + assert [str(r) for r in x] == [ + '-0.86113631159405258', + '-0.33998104358485626', + '0.33998104358485626', + '0.86113631159405258'] + assert [str(r) for r in w] == [ + '0.34785484513745386', + '0.65214515486254614', + '0.65214515486254614', + '0.34785484513745386'] + + +def test_legendre_precise(): + x, w = gauss_legendre(3, 40) + assert [str(r) for r in x] == [ + '-0.7745966692414833770358530799564799221666', + '0', + '0.7745966692414833770358530799564799221666'] + assert [str(r) for r in w] == [ + '0.5555555555555555555555555555555555555556', + '0.8888888888888888888888888888888888888889', + '0.5555555555555555555555555555555555555556'] + + +def test_laguerre(): + x, w = gauss_laguerre(1, 17) + assert [str(r) for r in x] == ['1.0000000000000000'] + assert [str(r) for r in w] == ['1.0000000000000000'] + + x, w = gauss_laguerre(2, 17) + assert [str(r) for r in x] == [ + '0.58578643762690495', + '3.4142135623730950'] + assert [str(r) for r in w] == [ + '0.85355339059327376', + '0.14644660940672624'] + + x, w = gauss_laguerre(3, 17) + assert [str(r) for r in x] == [ + '0.41577455678347908', + '2.2942803602790417', + '6.2899450829374792', + ] + assert [str(r) for r in w] == [ + '0.71109300992917302', + '0.27851773356924085', + '0.010389256501586136', + ] + + x, w = gauss_laguerre(4, 17) + assert [str(r) for r in x] == [ + '0.32254768961939231', + '1.7457611011583466', + '4.5366202969211280', + '9.3950709123011331'] + assert [str(r) for r in w] == [ + '0.60315410434163360', + '0.35741869243779969', + '0.038887908515005384', + '0.00053929470556132745'] + + x, w = gauss_laguerre(5, 17) + assert [str(r) for r in x] == [ + '0.26356031971814091', + '1.4134030591065168', + '3.5964257710407221', + '7.0858100058588376', + '12.640800844275783'] + assert [str(r) for r in w] == [ + '0.52175561058280865', + '0.39866681108317593', + '0.075942449681707595', + '0.0036117586799220485', + '2.3369972385776228e-5'] + + +def test_laguerre_precise(): + x, w = gauss_laguerre(3, 40) + assert [str(r) for r in x] == [ + '0.4157745567834790833115338731282744735466', + '2.294280360279041719822050361359593868960', + '6.289945082937479196866415765512131657493'] + assert [str(r) for r in w] == [ + '0.7110930099291730154495901911425944313094', + '0.2785177335692408488014448884567264810349', + '0.01038925650158613574896492040067908765572'] + + +def test_hermite(): + x, w = gauss_hermite(1, 17) + assert [str(r) for r in x] == ['0'] + assert [str(r) for r in w] == ['1.7724538509055160'] + + x, w = gauss_hermite(2, 17) + assert [str(r) for r in x] == [ + '-0.70710678118654752', + '0.70710678118654752'] + assert [str(r) for r in w] == [ + '0.88622692545275801', + '0.88622692545275801'] + + x, w = gauss_hermite(3, 17) + assert [str(r) for r in x] == [ + '-1.2247448713915890', + '0', + '1.2247448713915890'] + assert [str(r) for r in w] == [ + '0.29540897515091934', + '1.1816359006036774', + '0.29540897515091934'] + + x, w = gauss_hermite(4, 17) + assert [str(r) for r in x] == [ + '-1.6506801238857846', + '-0.52464762327529032', + '0.52464762327529032', + '1.6506801238857846'] + assert [str(r) for r in w] == [ + '0.081312835447245177', + '0.80491409000551284', + '0.80491409000551284', + '0.081312835447245177'] + + x, w = gauss_hermite(5, 17) + assert [str(r) for r in x] == [ + '-2.0201828704560856', + '-0.95857246461381851', + '0', + '0.95857246461381851', + '2.0201828704560856'] + assert [str(r) for r in w] == [ + '0.019953242059045913', + '0.39361932315224116', + '0.94530872048294188', + '0.39361932315224116', + '0.019953242059045913'] + + +def test_hermite_precise(): + x, w = gauss_hermite(3, 40) + assert [str(r) for r in x] == [ + '-1.224744871391589049098642037352945695983', + '0', + '1.224744871391589049098642037352945695983'] + assert [str(r) for r in w] == [ + '0.2954089751509193378830279138901908637996', + '1.181635900603677351532111655560763455198', + '0.2954089751509193378830279138901908637996'] + + +def test_gen_laguerre(): + x, w = gauss_gen_laguerre(1, Rational(-1, 2), 17) + assert [str(r) for r in x] == ['0.50000000000000000'] + assert [str(r) for r in w] == ['1.7724538509055160'] + + x, w = gauss_gen_laguerre(2, Rational(-1, 2), 17) + assert [str(r) for r in x] == [ + '0.27525512860841095', + '2.7247448713915890'] + assert [str(r) for r in w] == [ + '1.6098281800110257', + '0.16262567089449035'] + + x, w = gauss_gen_laguerre(3, Rational(-1, 2), 17) + assert [str(r) for r in x] == [ + '0.19016350919348813', + '1.7844927485432516', + '5.5253437422632603'] + assert [str(r) for r in w] == [ + '1.4492591904487850', + '0.31413464064571329', + '0.0090600198110176913'] + + x, w = gauss_gen_laguerre(4, Rational(-1, 2), 17) + assert [str(r) for r in x] == [ + '0.14530352150331709', + '1.3390972881263614', + '3.9269635013582872', + '8.5886356890120343'] + assert [str(r) for r in w] == [ + '1.3222940251164826', + '0.41560465162978376', + '0.034155966014826951', + '0.00039920814442273524'] + + x, w = gauss_gen_laguerre(5, Rational(-1, 2), 17) + assert [str(r) for r in x] == [ + '0.11758132021177814', + '1.0745620124369040', + '3.0859374437175500', + '6.4147297336620305', + '11.807189489971737'] + assert [str(r) for r in w] == [ + '1.2217252674706516', + '0.48027722216462937', + '0.067748788910962126', + '0.0026872914935624654', + '1.5280865710465241e-5'] + + x, w = gauss_gen_laguerre(1, 2, 17) + assert [str(r) for r in x] == ['3.0000000000000000'] + assert [str(r) for r in w] == ['2.0000000000000000'] + + x, w = gauss_gen_laguerre(2, 2, 17) + assert [str(r) for r in x] == [ + '2.0000000000000000', + '6.0000000000000000'] + assert [str(r) for r in w] == [ + '1.5000000000000000', + '0.50000000000000000'] + + x, w = gauss_gen_laguerre(3, 2, 17) + assert [str(r) for r in x] == [ + '1.5173870806774125', + '4.3115831337195203', + '9.1710297856030672'] + assert [str(r) for r in w] == [ + '1.0374949614904253', + '0.90575000470306537', + '0.056755033806509347'] + + x, w = gauss_gen_laguerre(4, 2, 17) + assert [str(r) for r in x] == [ + '1.2267632635003021', + '3.4125073586969460', + '6.9026926058516134', + '12.458036771951139'] + assert [str(r) for r in w] == [ + '0.72552499769865438', + '1.0634242919791946', + '0.20669613102835355', + '0.0043545792937974889'] + + x, w = gauss_gen_laguerre(5, 2, 17) + assert [str(r) for r in x] == [ + '1.0311091440933816', + '2.8372128239538217', + '5.6202942725987079', + '9.6829098376640271', + '15.828473921690062'] + assert [str(r) for r in w] == [ + '0.52091739683509184', + '1.0667059331592211', + '0.38354972366693113', + '0.028564233532974658', + '0.00026271280578124935'] + + +def test_gen_laguerre_precise(): + x, w = gauss_gen_laguerre(3, Rational(-1, 2), 40) + assert [str(r) for r in x] == [ + '0.1901635091934881328718554276203028970878', + '1.784492748543251591186722461957367638500', + '5.525343742263260275941422110422329464413'] + assert [str(r) for r in w] == [ + '1.449259190448785048183829411195134343108', + '0.3141346406457132878326231270167565378246', + '0.009060019811017691281714945129254301865020'] + + x, w = gauss_gen_laguerre(3, 2, 40) + assert [str(r) for r in x] == [ + '1.517387080677412495020323111016672547482', + '4.311583133719520302881184669723530562299', + '9.171029785603067202098492219259796890218'] + assert [str(r) for r in w] == [ + '1.037494961490425285817554606541269153041', + '0.9057500047030653669269785048806009945254', + '0.05675503380650934725546688857812985243312'] + + +def test_chebyshev_t(): + x, w = gauss_chebyshev_t(1, 17) + assert [str(r) for r in x] == ['0'] + assert [str(r) for r in w] == ['3.1415926535897932'] + + x, w = gauss_chebyshev_t(2, 17) + assert [str(r) for r in x] == [ + '0.70710678118654752', + '-0.70710678118654752'] + assert [str(r) for r in w] == [ + '1.5707963267948966', + '1.5707963267948966'] + + x, w = gauss_chebyshev_t(3, 17) + assert [str(r) for r in x] == [ + '0.86602540378443865', + '0', + '-0.86602540378443865'] + assert [str(r) for r in w] == [ + '1.0471975511965977', + '1.0471975511965977', + '1.0471975511965977'] + + x, w = gauss_chebyshev_t(4, 17) + assert [str(r) for r in x] == [ + '0.92387953251128676', + '0.38268343236508977', + '-0.38268343236508977', + '-0.92387953251128676'] + assert [str(r) for r in w] == [ + '0.78539816339744831', + '0.78539816339744831', + '0.78539816339744831', + '0.78539816339744831'] + + x, w = gauss_chebyshev_t(5, 17) + assert [str(r) for r in x] == [ + '0.95105651629515357', + '0.58778525229247313', + '0', + '-0.58778525229247313', + '-0.95105651629515357'] + assert [str(r) for r in w] == [ + '0.62831853071795865', + '0.62831853071795865', + '0.62831853071795865', + '0.62831853071795865', + '0.62831853071795865'] + + +def test_chebyshev_t_precise(): + x, w = gauss_chebyshev_t(3, 40) + assert [str(r) for r in x] == [ + '0.8660254037844386467637231707529361834714', + '0', + '-0.8660254037844386467637231707529361834714'] + assert [str(r) for r in w] == [ + '1.047197551196597746154214461093167628066', + '1.047197551196597746154214461093167628066', + '1.047197551196597746154214461093167628066'] + + +def test_chebyshev_u(): + x, w = gauss_chebyshev_u(1, 17) + assert [str(r) for r in x] == ['0'] + assert [str(r) for r in w] == ['1.5707963267948966'] + + x, w = gauss_chebyshev_u(2, 17) + assert [str(r) for r in x] == [ + '0.50000000000000000', + '-0.50000000000000000'] + assert [str(r) for r in w] == [ + '0.78539816339744831', + '0.78539816339744831'] + + x, w = gauss_chebyshev_u(3, 17) + assert [str(r) for r in x] == [ + '0.70710678118654752', + '0', + '-0.70710678118654752'] + assert [str(r) for r in w] == [ + '0.39269908169872415', + '0.78539816339744831', + '0.39269908169872415'] + + x, w = gauss_chebyshev_u(4, 17) + assert [str(r) for r in x] == [ + '0.80901699437494742', + '0.30901699437494742', + '-0.30901699437494742', + '-0.80901699437494742'] + assert [str(r) for r in w] == [ + '0.21707871342270599', + '0.56831944997474231', + '0.56831944997474231', + '0.21707871342270599'] + + x, w = gauss_chebyshev_u(5, 17) + assert [str(r) for r in x] == [ + '0.86602540378443865', + '0.50000000000000000', + '0', + '-0.50000000000000000', + '-0.86602540378443865'] + assert [str(r) for r in w] == [ + '0.13089969389957472', + '0.39269908169872415', + '0.52359877559829887', + '0.39269908169872415', + '0.13089969389957472'] + + +def test_chebyshev_u_precise(): + x, w = gauss_chebyshev_u(3, 40) + assert [str(r) for r in x] == [ + '0.7071067811865475244008443621048490392848', + '0', + '-0.7071067811865475244008443621048490392848'] + assert [str(r) for r in w] == [ + '0.3926990816987241548078304229099378605246', + '0.7853981633974483096156608458198757210493', + '0.3926990816987241548078304229099378605246'] + + +def test_jacobi(): + x, w = gauss_jacobi(1, Rational(-1, 2), S.Half, 17) + assert [str(r) for r in x] == ['0.50000000000000000'] + assert [str(r) for r in w] == ['3.1415926535897932'] + + x, w = gauss_jacobi(2, Rational(-1, 2), S.Half, 17) + assert [str(r) for r in x] == [ + '-0.30901699437494742', + '0.80901699437494742'] + assert [str(r) for r in w] == [ + '0.86831485369082398', + '2.2732777998989693'] + + x, w = gauss_jacobi(3, Rational(-1, 2), S.Half, 17) + assert [str(r) for r in x] == [ + '-0.62348980185873353', + '0.22252093395631440', + '0.90096886790241913'] + assert [str(r) for r in w] == [ + '0.33795476356635433', + '1.0973322242791115', + '1.7063056657443274'] + + x, w = gauss_jacobi(4, Rational(-1, 2), S.Half, 17) + assert [str(r) for r in x] == [ + '-0.76604444311897804', + '-0.17364817766693035', + '0.50000000000000000', + '0.93969262078590838'] + assert [str(r) for r in w] == [ + '0.16333179083642836', + '0.57690240318269103', + '1.0471975511965977', + '1.3541609083740761'] + + x, w = gauss_jacobi(5, Rational(-1, 2), S.Half, 17) + assert [str(r) for r in x] == [ + '-0.84125353283118117', + '-0.41541501300188643', + '0.14231483827328514', + '0.65486073394528506', + '0.95949297361449739'] + assert [str(r) for r in w] == [ + '0.090675770007435372', + '0.33391416373675607', + '0.65248870981926643', + '0.94525424081394926', + '1.1192597692123861'] + + x, w = gauss_jacobi(1, 2, 3, 17) + assert [str(r) for r in x] == ['0.14285714285714286'] + assert [str(r) for r in w] == ['1.0666666666666667'] + + x, w = gauss_jacobi(2, 2, 3, 17) + assert [str(r) for r in x] == [ + '-0.24025307335204215', + '0.46247529557426437'] + assert [str(r) for r in w] == [ + '0.48514624517838660', + '0.58152042148828007'] + + x, w = gauss_jacobi(3, 2, 3, 17) + assert [str(r) for r in x] == [ + '-0.46115870378089762', + '0.10438533038323902', + '0.62950064612493132'] + assert [str(r) for r in w] == [ + '0.17937613502213266', + '0.61595640991147154', + '0.27133412173306246'] + + x, w = gauss_jacobi(4, 2, 3, 17) + assert [str(r) for r in x] == [ + '-0.59903470850824782', + '-0.14761105199952565', + '0.32554377081188859', + '0.72879429738819258'] + assert [str(r) for r in w] == [ + '0.067809641836772187', + '0.38956404952032481', + '0.47995970868024150', + '0.12933326662932816'] + + x, w = gauss_jacobi(5, 2, 3, 17) + assert [str(r) for r in x] == [ + '-0.69045775012676106', + '-0.32651993134900065', + '0.082337849552034905', + '0.47517887061283164', + '0.79279429464422850'] + assert [str(r) for r in w] == [ + '0.027410178066337099', + '0.21291786060364828', + '0.43908437944395081', + '0.32220656547221822', + '0.065047683080512268'] + + +def test_jacobi_precise(): + x, w = gauss_jacobi(3, Rational(-1, 2), S.Half, 40) + assert [str(r) for r in x] == [ + '-0.6234898018587335305250048840042398106323', + '0.2225209339563144042889025644967947594664', + '0.9009688679024191262361023195074450511659'] + assert [str(r) for r in w] == [ + '0.3379547635663543330553835737094171534907', + '1.097332224279111467485302294320899710461', + '1.706305665744327437921957515249186020246'] + + x, w = gauss_jacobi(3, 2, 3, 40) + assert [str(r) for r in x] == [ + '-0.4611587037808976179121958105554375981274', + '0.1043853303832390210914918407615869143233', + '0.6295006461249313240934312425211234110769'] + assert [str(r) for r in w] == [ + '0.1793761350221326596137764371503859752628', + '0.6159564099114715430909548532229749439714', + '0.2713341217330624639619353762933057474325'] + + +def test_lobatto(): + x, w = gauss_lobatto(2, 17) + assert [str(r) for r in x] == [ + '-1', + '1'] + assert [str(r) for r in w] == [ + '1.0000000000000000', + '1.0000000000000000'] + + x, w = gauss_lobatto(3, 17) + assert [str(r) for r in x] == [ + '-1', + '0', + '1'] + assert [str(r) for r in w] == [ + '0.33333333333333333', + '1.3333333333333333', + '0.33333333333333333'] + + x, w = gauss_lobatto(4, 17) + assert [str(r) for r in x] == [ + '-1', + '-0.44721359549995794', + '0.44721359549995794', + '1'] + assert [str(r) for r in w] == [ + '0.16666666666666667', + '0.83333333333333333', + '0.83333333333333333', + '0.16666666666666667'] + + x, w = gauss_lobatto(5, 17) + assert [str(r) for r in x] == [ + '-1', + '-0.65465367070797714', + '0', + '0.65465367070797714', + '1'] + assert [str(r) for r in w] == [ + '0.10000000000000000', + '0.54444444444444444', + '0.71111111111111111', + '0.54444444444444444', + '0.10000000000000000'] + + +def test_lobatto_precise(): + x, w = gauss_lobatto(3, 40) + assert [str(r) for r in x] == [ + '-1', + '0', + '1'] + assert [str(r) for r in w] == [ + '0.3333333333333333333333333333333333333333', + '1.333333333333333333333333333333333333333', + '0.3333333333333333333333333333333333333333'] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_rationaltools.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_rationaltools.py new file mode 100644 index 0000000000000000000000000000000000000000..809bf30c1c35f80e2a0b15c1e639603eab28a250 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_rationaltools.py @@ -0,0 +1,183 @@ +from sympy.core.numbers import (I, Rational) +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, symbols) +from sympy.functions.elementary.exponential import log +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import atan +from sympy.integrals.integrals import integrate +from sympy.polys.polytools import Poly +from sympy.simplify.simplify import simplify + +from sympy.integrals.rationaltools import ratint, ratint_logpart, log_to_atan + +from sympy.abc import a, b, x, t + +half = S.Half + + +def test_ratint(): + assert ratint(S.Zero, x) == 0 + assert ratint(S(7), x) == 7*x + + assert ratint(x, x) == x**2/2 + assert ratint(2*x, x) == x**2 + assert ratint(-2*x, x) == -x**2 + + assert ratint(8*x**7 + 2*x + 1, x) == x**8 + x**2 + x + + f = S.One + g = x + 1 + + assert ratint(f / g, x) == log(x + 1) + assert ratint((f, g), x) == log(x + 1) + + f = x**3 - x + g = x - 1 + + assert ratint(f/g, x) == x**3/3 + x**2/2 + + f = x + g = (x - a)*(x + a) + + assert ratint(f/g, x) == log(x**2 - a**2)/2 + + f = S.One + g = x**2 + 1 + + assert ratint(f/g, x, real=None) == atan(x) + assert ratint(f/g, x, real=True) == atan(x) + + assert ratint(f/g, x, real=False) == I*log(x + I)/2 - I*log(x - I)/2 + + f = S(36) + g = x**5 - 2*x**4 - 2*x**3 + 4*x**2 + x - 2 + + assert ratint(f/g, x) == \ + -4*log(x + 1) + 4*log(x - 2) + (12*x + 6)/(x**2 - 1) + + f = x**4 - 3*x**2 + 6 + g = x**6 - 5*x**4 + 5*x**2 + 4 + + assert ratint(f/g, x) == \ + atan(x) + atan(x**3) + atan(x/2 - Rational(3, 2)*x**3 + S.Half*x**5) + + f = x**7 - 24*x**4 - 4*x**2 + 8*x - 8 + g = x**8 + 6*x**6 + 12*x**4 + 8*x**2 + + assert ratint(f/g, x) == \ + (4 + 6*x + 8*x**2 + 3*x**3)/(4*x + 4*x**3 + x**5) + log(x) + + assert ratint((x**3*f)/(x*g), x) == \ + -(12 - 16*x + 6*x**2 - 14*x**3)/(4 + 4*x**2 + x**4) - \ + 5*sqrt(2)*atan(x*sqrt(2)/2) + S.Half*x**2 - 3*log(2 + x**2) + + f = x**5 - x**4 + 4*x**3 + x**2 - x + 5 + g = x**4 - 2*x**3 + 5*x**2 - 4*x + 4 + + assert ratint(f/g, x) == \ + x + S.Half*x**2 + S.Half*log(2 - x + x**2) + (9 - 4*x)/(7*x**2 - 7*x + 14) + \ + 13*sqrt(7)*atan(Rational(-1, 7)*sqrt(7) + 2*x*sqrt(7)/7)/49 + + assert ratint(1/(x**2 + x + 1), x) == \ + 2*sqrt(3)*atan(sqrt(3)/3 + 2*x*sqrt(3)/3)/3 + + assert ratint(1/(x**3 + 1), x) == \ + -log(1 - x + x**2)/6 + log(1 + x)/3 + sqrt(3)*atan(-sqrt(3) + /3 + 2*x*sqrt(3)/3)/3 + + assert ratint(1/(x**2 + x + 1), x, real=False) == \ + -I*3**half*log(half + x - half*I*3**half)/3 + \ + I*3**half*log(half + x + half*I*3**half)/3 + + assert ratint(1/(x**3 + 1), x, real=False) == log(1 + x)/3 + \ + (Rational(-1, 6) + I*3**half/6)*log(-half + x + I*3**half/2) + \ + (Rational(-1, 6) - I*3**half/6)*log(-half + x - I*3**half/2) + + # issue 4991 + assert ratint(1/(x*(a + b*x)**3), x) == \ + (3*a + 2*b*x)/(2*a**4 + 4*a**3*b*x + 2*a**2*b**2*x**2) + ( + log(x) - log(a/b + x))/a**3 + + assert ratint(x/(1 - x**2), x) == -log(x**2 - 1)/2 + assert ratint(-x/(1 - x**2), x) == log(x**2 - 1)/2 + + assert ratint((x/4 - 4/(1 - x)).diff(x), x) == x/4 + 4/(x - 1) + + ans = atan(x) + assert ratint(1/(x**2 + 1), x, symbol=x) == ans + assert ratint(1/(x**2 + 1), x, symbol='x') == ans + assert ratint(1/(x**2 + 1), x, symbol=a) == ans + # this asserts that as_dummy must return a unique symbol + # even if the symbol is already a Dummy + d = Dummy() + assert ratint(1/(d**2 + 1), d, symbol=d) == atan(d) + + +def test_ratint_logpart(): + assert ratint_logpart(x, x**2 - 9, x, t) == \ + [(Poly(x**2 - 9, x), Poly(-2*t + 1, t))] + assert ratint_logpart(x**2, x**3 - 5, x, t) == \ + [(Poly(x**3 - 5, x), Poly(-3*t + 1, t))] + + +def test_issue_5414(): + assert ratint(1/(x**2 + 16), x) == atan(x/4)/4 + + +def test_issue_5249(): + assert ratint( + 1/(x**2 + a**2), x) == (-I*log(-I*a + x)/2 + I*log(I*a + x)/2)/a + + +def test_issue_5817(): + a, b, c = symbols('a,b,c', positive=True) + + assert simplify(ratint(a/(b*c*x**2 + a**2 + b*a), x)) == \ + sqrt(a)*atan(sqrt( + b)*sqrt(c)*x/(sqrt(a)*sqrt(a + b)))/(sqrt(b)*sqrt(c)*sqrt(a + b)) + + +def test_issue_5981(): + u = symbols('u') + assert integrate(1/(u**2 + 1)) == atan(u) + +def test_issue_10488(): + a,b,c,x = symbols('a b c x', positive=True) + assert integrate(x/(a*x+b),x) == x/a - b*log(a*x + b)/a**2 + + +def test_issues_8246_12050_13501_14080(): + a = symbols('a', nonzero=True) + assert integrate(a/(x**2 + a**2), x) == atan(x/a) + assert integrate(1/(x**2 + a**2), x) == atan(x/a)/a + assert integrate(1/(1 + a**2*x**2), x) == atan(a*x)/a + + +def test_issue_6308(): + k, a0 = symbols('k a0', real=True) + assert integrate((x**2 + 1 - k**2)/(x**2 + 1 + a0**2), x) == \ + x - (a0**2 + k**2)*atan(x/sqrt(a0**2 + 1))/sqrt(a0**2 + 1) + + +def test_issue_5907(): + a = symbols('a', nonzero=True) + assert integrate(1/(x**2 + a**2)**2, x) == \ + x/(2*a**4 + 2*a**2*x**2) + atan(x/a)/(2*a**3) + + +def test_log_to_atan(): + f, g = (Poly(x + S.Half, x, domain='QQ'), Poly(sqrt(3)/2, x, domain='EX')) + fg_ans = 2*atan(2*sqrt(3)*x/3 + sqrt(3)/3) + assert log_to_atan(f, g) == fg_ans + assert log_to_atan(g, f) == -fg_ans + + +def test_issue_25896(): + # for both tests, C = 0 in log_to_real + # but this only has a log result + e = (2*x + 1)/(x**2 + x + 1) + 1/x + assert ratint(e, x) == log(x**3 + x**2 + x) + # while this has more + assert ratint((4*x + 7)/(x**2 + 4*x + 6) + 2/x, x) == ( + 2*log(x) + 2*log(x**2 + 4*x + 6) - sqrt(2)*atan( + sqrt(2)*x/2 + sqrt(2))/2) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_rde.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_rde.py new file mode 100644 index 0000000000000000000000000000000000000000..3c7df5ce05846dc270756cd878870bbff78ff976 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_rde.py @@ -0,0 +1,202 @@ +"""Most of these tests come from the examples in Bronstein's book.""" +from sympy.core.numbers import (I, Rational, oo) +from sympy.core.symbol import symbols +from sympy.polys.polytools import Poly +from sympy.integrals.risch import (DifferentialExtension, + NonElementaryIntegralException) +from sympy.integrals.rde import (order_at, order_at_oo, weak_normalizer, + normal_denom, special_denom, bound_degree, spde, solve_poly_rde, + no_cancel_equal, cancel_primitive, cancel_exp, rischDE) + +from sympy.testing.pytest import raises +from sympy.abc import x, t, z, n + +t0, t1, t2, k = symbols('t:3 k') + + +def test_order_at(): + a = Poly(t**4, t) + b = Poly((t**2 + 1)**3*t, t) + c = Poly((t**2 + 1)**6*t, t) + d = Poly((t**2 + 1)**10*t**10, t) + e = Poly((t**2 + 1)**100*t**37, t) + p1 = Poly(t, t) + p2 = Poly(1 + t**2, t) + assert order_at(a, p1, t) == 4 + assert order_at(b, p1, t) == 1 + assert order_at(c, p1, t) == 1 + assert order_at(d, p1, t) == 10 + assert order_at(e, p1, t) == 37 + assert order_at(a, p2, t) == 0 + assert order_at(b, p2, t) == 3 + assert order_at(c, p2, t) == 6 + assert order_at(d, p1, t) == 10 + assert order_at(e, p2, t) == 100 + assert order_at(Poly(0, t), Poly(t, t), t) is oo + assert order_at_oo(Poly(t**2 - 1, t), Poly(t + 1), t) == \ + order_at_oo(Poly(t - 1, t), Poly(1, t), t) == -1 + assert order_at_oo(Poly(0, t), Poly(1, t), t) is oo + +def test_weak_normalizer(): + a = Poly((1 + x)*t**5 + 4*t**4 + (-1 - 3*x)*t**3 - 4*t**2 + (-2 + 2*x)*t, t) + d = Poly(t**4 - 3*t**2 + 2, t) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + r = weak_normalizer(a, d, DE, z) + assert r == (Poly(t**5 - t**4 - 4*t**3 + 4*t**2 + 4*t - 4, t, domain='ZZ[x]'), + (Poly((1 + x)*t**2 + x*t, t, domain='ZZ[x]'), + Poly(t + 1, t, domain='ZZ[x]'))) + assert weak_normalizer(r[1][0], r[1][1], DE) == (Poly(1, t), r[1]) + r = weak_normalizer(Poly(1 + t**2), Poly(t**2 - 1, t), DE, z) + assert r == (Poly(t**4 - 2*t**2 + 1, t), (Poly(-3*t**2 + 1, t), Poly(t**2 - 1, t))) + assert weak_normalizer(r[1][0], r[1][1], DE, z) == (Poly(1, t), r[1]) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t**2)]}) + r = weak_normalizer(Poly(1 + t**2), Poly(t, t), DE, z) + assert r == (Poly(t, t), (Poly(0, t), Poly(1, t))) + assert weak_normalizer(r[1][0], r[1][1], DE, z) == (Poly(1, t), r[1]) + + +def test_normal_denom(): + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + raises(NonElementaryIntegralException, lambda: normal_denom(Poly(1, x), Poly(1, x), + Poly(1, x), Poly(x, x), DE)) + fa, fd = Poly(t**2 + 1, t), Poly(1, t) + ga, gd = Poly(1, t), Poly(t**2, t) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + assert normal_denom(fa, fd, ga, gd, DE) == \ + (Poly(t, t), (Poly(t**3 - t**2 + t - 1, t), Poly(1, t)), (Poly(1, t), + Poly(1, t)), Poly(t, t)) + + +def test_special_denom(): + # TODO: add more tests here + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert special_denom(Poly(1, t), Poly(t**2, t), Poly(1, t), Poly(t**2 - 1, t), + Poly(t, t), DE) == \ + (Poly(1, t), Poly(t**2 - 1, t), Poly(t**2 - 1, t), Poly(t, t)) +# assert special_denom(Poly(1, t), Poly(2*x, t), Poly((1 + 2*x)*t, t), DE) == 1 + + # issue 3940 + # Note, this isn't a very good test, because the denominator is just 1, + # but at least it tests the exp cancellation case + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-2*x*t0, t0), + Poly(I*k*t1, t1)]}) + DE.decrement_level() + assert special_denom(Poly(1, t0), Poly(I*k, t0), Poly(1, t0), Poly(t0, t0), + Poly(1, t0), DE) == \ + (Poly(1, t0, domain='ZZ'), Poly(I*k, t0, domain='ZZ_I[k,x]'), + Poly(t0, t0, domain='ZZ'), Poly(1, t0, domain='ZZ')) + + + assert special_denom(Poly(1, t), Poly(t**2, t), Poly(1, t), Poly(t**2 - 1, t), + Poly(t, t), DE, case='tan') == \ + (Poly(1, t, t0, domain='ZZ'), Poly(t**2, t0, t, domain='ZZ[x]'), + Poly(t, t, t0, domain='ZZ'), Poly(1, t0, domain='ZZ')) + + raises(ValueError, lambda: special_denom(Poly(1, t), Poly(t**2, t), Poly(1, t), Poly(t**2 - 1, t), + Poly(t, t), DE, case='unrecognized_case')) + + +def test_bound_degree_fail(): + # Primitive + DE = DifferentialExtension(extension={'D': [Poly(1, x), + Poly(t0/x**2, t0), Poly(1/x, t)]}) + assert bound_degree(Poly(t**2, t), Poly(-(1/x**2*t**2 + 1/x), t), + Poly((2*x - 1)*t**4 + (t0 + x)/x*t**3 - (t0 + 4*x**2)/2*x*t**2 + x*t, + t), DE) == 3 + + +def test_bound_degree(): + # Base + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + assert bound_degree(Poly(1, x), Poly(-2*x, x), Poly(1, x), DE) == 0 + + # Primitive (see above test_bound_degree_fail) + # TODO: Add test for when the degree bound becomes larger after limited_integrate + # TODO: Add test for db == da - 1 case + + # Exp + # TODO: Add tests + # TODO: Add test for when the degree becomes larger after parametric_log_deriv() + + # Nonlinear + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + assert bound_degree(Poly(t, t), Poly((t - 1)*(t**2 + 1), t), Poly(1, t), DE) == 0 + + +def test_spde(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + raises(NonElementaryIntegralException, lambda: spde(Poly(t, t), Poly((t - 1)*(t**2 + 1), t), Poly(1, t), 0, DE)) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert spde(Poly(t**2 + x*t*2 + x**2, t), Poly(t**2/x**2 + (2/x - 1)*t, t), + Poly(t**2/x**2 + (2/x - 1)*t, t), 0, DE) == \ + (Poly(0, t), Poly(0, t), 0, Poly(0, t), Poly(1, t, domain='ZZ(x)')) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t0/x**2, t0), Poly(1/x, t)]}) + assert spde(Poly(t**2, t), Poly(-t**2/x**2 - 1/x, t), + Poly((2*x - 1)*t**4 + (t0 + x)/x*t**3 - (t0 + 4*x**2)/(2*x)*t**2 + x*t, t), 3, DE) == \ + (Poly(0, t), Poly(0, t), 0, Poly(0, t), + Poly(t0*t**2/2 + x**2*t**2 - x**2*t, t, domain='ZZ(x,t0)')) + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + assert spde(Poly(x**2 + x + 1, x), Poly(-2*x - 1, x), Poly(x**5/2 + + 3*x**4/4 + x**3 - x**2 + 1, x), 4, DE) == \ + (Poly(0, x, domain='QQ'), Poly(x/2 - Rational(1, 4), x), 2, Poly(x**2 + x + 1, x), Poly(x*Rational(5, 4), x)) + assert spde(Poly(x**2 + x + 1, x), Poly(-2*x - 1, x), Poly(x**5/2 + + 3*x**4/4 + x**3 - x**2 + 1, x), n, DE) == \ + (Poly(0, x, domain='QQ'), Poly(x/2 - Rational(1, 4), x), -2 + n, Poly(x**2 + x + 1, x), Poly(x*Rational(5, 4), x)) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1, t)]}) + raises(NonElementaryIntegralException, lambda: spde(Poly((t - 1)*(t**2 + 1)**2, t), Poly((t - 1)*(t**2 + 1), t), Poly(1, t), 0, DE)) + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + assert spde(Poly(x**2 - x, x), Poly(1, x), Poly(9*x**4 - 10*x**3 + 2*x**2, x), 4, DE) == \ + (Poly(0, x, domain='ZZ'), Poly(0, x), 0, Poly(0, x), Poly(3*x**3 - 2*x**2, x, domain='QQ')) + assert spde(Poly(x**2 - x, x), Poly(x**2 - 5*x + 3, x), Poly(x**7 - x**6 - 2*x**4 + 3*x**3 - x**2, x), 5, DE) == \ + (Poly(1, x, domain='QQ'), Poly(x + 1, x, domain='QQ'), 1, Poly(x**4 - x**3, x), Poly(x**3 - x**2, x, domain='QQ')) + +def test_solve_poly_rde_no_cancel(): + # deg(b) large + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t**2, t)]}) + assert solve_poly_rde(Poly(t**2 + 1, t), Poly(t**3 + (x + 1)*t**2 + t + x + 2, t), + oo, DE) == Poly(t + x, t) + # deg(b) small + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + assert solve_poly_rde(Poly(0, x), Poly(x/2 - Rational(1, 4), x), oo, DE) == \ + Poly(x**2/4 - x/4, x) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + assert solve_poly_rde(Poly(2, t), Poly(t**2 + 2*t + 3, t), 1, DE) == \ + Poly(t + 1, t, x) + # deg(b) == deg(D) - 1 + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + assert no_cancel_equal(Poly(1 - t, t), + Poly(t**3 + t**2 - 2*x*t - 2*x, t), oo, DE) == \ + (Poly(t**2, t), 1, Poly((-2 - 2*x)*t - 2*x, t)) + + +def test_solve_poly_rde_cancel(): + # exp + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert cancel_exp(Poly(2*x, t), Poly(2*x, t), 0, DE) == \ + Poly(1, t) + assert cancel_exp(Poly(2*x, t), Poly((1 + 2*x)*t, t), 1, DE) == \ + Poly(t, t) + # TODO: Add more exp tests, including tests that require is_deriv_in_field() + + # primitive + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + + # If the DecrementLevel context manager is working correctly, this shouldn't + # cause any problems with the further tests. + raises(NonElementaryIntegralException, lambda: cancel_primitive(Poly(1, t), Poly(t, t), oo, DE)) + + assert cancel_primitive(Poly(1, t), Poly(t + 1/x, t), 2, DE) == \ + Poly(t, t) + assert cancel_primitive(Poly(4*x, t), Poly(4*x*t**2 + 2*t/x, t), 3, DE) == \ + Poly(t**2, t) + + # TODO: Add more primitive tests, including tests that require is_deriv_in_field() + + +def test_rischDE(): + # TODO: Add more tests for rischDE, including ones from the text + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + DE.decrement_level() + assert rischDE(Poly(-2*x, x), Poly(1, x), Poly(1 - 2*x - 2*x**2, x), + Poly(1, x), DE) == \ + (Poly(x + 1, x), Poly(1, x)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_risch.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_risch.py new file mode 100644 index 0000000000000000000000000000000000000000..68be260e1f3d42fb14c790afe6bda1768e777666 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_risch.py @@ -0,0 +1,763 @@ +"""Most of these tests come from the examples in Bronstein's book.""" +from sympy.core.function import (Function, Lambda, diff, expand_log) +from sympy.core.numbers import (I, Rational, pi) +from sympy.core.relational import Ne +from sympy.core.singleton import S +from sympy.core.symbol import (Symbol, symbols) +from sympy.functions.elementary.exponential import (exp, log) +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.piecewise import Piecewise +from sympy.functions.elementary.trigonometric import (atan, sin, tan) +from sympy.polys.polytools import (Poly, cancel, factor) +from sympy.integrals.risch import (gcdex_diophantine, frac_in, as_poly_1t, + derivation, splitfactor, splitfactor_sqf, canonical_representation, + hermite_reduce, polynomial_reduce, residue_reduce, residue_reduce_to_basic, + integrate_primitive, integrate_hyperexponential_polynomial, + integrate_hyperexponential, integrate_hypertangent_polynomial, + integrate_nonlinear_no_specials, integer_powers, DifferentialExtension, + risch_integrate, DecrementLevel, NonElementaryIntegral, recognize_log_derivative, + recognize_derivative, laurent_series) +from sympy.testing.pytest import raises + +from sympy.abc import x, t, nu, z, a, y +t0, t1, t2 = symbols('t:3') +i = Symbol('i') + +def test_gcdex_diophantine(): + assert gcdex_diophantine(Poly(x**4 - 2*x**3 - 6*x**2 + 12*x + 15), + Poly(x**3 + x**2 - 4*x - 4), Poly(x**2 - 1)) == \ + (Poly((-x**2 + 4*x - 3)/5), Poly((x**3 - 7*x**2 + 16*x - 10)/5)) + assert gcdex_diophantine(Poly(x**3 + 6*x + 7), Poly(x**2 + 3*x + 2), Poly(x + 1)) == \ + (Poly(1/13, x, domain='QQ'), Poly(-1/13*x + 3/13, x, domain='QQ')) + + +def test_frac_in(): + assert frac_in(Poly((x + 1)/x*t, t), x) == \ + (Poly(t*x + t, x), Poly(x, x)) + assert frac_in((x + 1)/x*t, x) == \ + (Poly(t*x + t, x), Poly(x, x)) + assert frac_in((Poly((x + 1)/x*t, t), Poly(t + 1, t)), x) == \ + (Poly(t*x + t, x), Poly((1 + t)*x, x)) + raises(ValueError, lambda: frac_in((x + 1)/log(x)*t, x)) + assert frac_in(Poly((2 + 2*x + x*(1 + x))/(1 + x)**2, t), x, cancel=True) == \ + (Poly(x + 2, x), Poly(x + 1, x)) + + +def test_as_poly_1t(): + assert as_poly_1t(2/t + t, t, z) in [ + Poly(t + 2*z, t, z), Poly(t + 2*z, z, t)] + assert as_poly_1t(2/t + 3/t**2, t, z) in [ + Poly(2*z + 3*z**2, t, z), Poly(2*z + 3*z**2, z, t)] + assert as_poly_1t(2/((exp(2) + 1)*t), t, z) in [ + Poly(2/(exp(2) + 1)*z, t, z), Poly(2/(exp(2) + 1)*z, z, t)] + assert as_poly_1t(2/((exp(2) + 1)*t) + t, t, z) in [ + Poly(t + 2/(exp(2) + 1)*z, t, z), Poly(t + 2/(exp(2) + 1)*z, z, t)] + assert as_poly_1t(S.Zero, t, z) == Poly(0, t, z) + + +def test_derivation(): + p = Poly(4*x**4*t**5 + (-4*x**3 - 4*x**4)*t**4 + (-3*x**2 + 2*x**3)*t**3 + + (2*x + 7*x**2 + 2*x**3)*t**2 + (1 - 4*x - 4*x**2)*t - 1 + 2*x, t) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-t**2 - 3/(2*x)*t + 1/(2*x), t)]}) + assert derivation(p, DE) == Poly(-20*x**4*t**6 + (2*x**3 + 16*x**4)*t**5 + + (21*x**2 + 12*x**3)*t**4 + (x*Rational(7, 2) - 25*x**2 - 12*x**3)*t**3 + + (-5 - x*Rational(15, 2) + 7*x**2)*t**2 - (3 - 8*x - 10*x**2 - 4*x**3)/(2*x)*t + + (1 - 4*x**2)/(2*x), t) + assert derivation(Poly(1, t), DE) == Poly(0, t) + assert derivation(Poly(t, t), DE) == DE.d + assert derivation(Poly(t**2 + 1/x*t + (1 - 2*x)/(4*x**2), t), DE) == \ + Poly(-2*t**3 - 4/x*t**2 - (5 - 2*x)/(2*x**2)*t - (1 - 2*x)/(2*x**3), t, domain='ZZ(x)') + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t1), Poly(t, t)]}) + assert derivation(Poly(x*t*t1, t), DE) == Poly(t*t1 + x*t*t1 + t, t) + assert derivation(Poly(x*t*t1, t), DE, coefficientD=True) == \ + Poly((1 + t1)*t, t) + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + assert derivation(Poly(x, x), DE) == Poly(1, x) + # Test basic option + assert derivation((x + 1)/(x - 1), DE, basic=True) == -2/(1 - 2*x + x**2) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert derivation((t + 1)/(t - 1), DE, basic=True) == -2*t/(1 - 2*t + t**2) + assert derivation(t + 1, DE, basic=True) == t + + +def test_splitfactor(): + p = Poly(4*x**4*t**5 + (-4*x**3 - 4*x**4)*t**4 + (-3*x**2 + 2*x**3)*t**3 + + (2*x + 7*x**2 + 2*x**3)*t**2 + (1 - 4*x - 4*x**2)*t - 1 + 2*x, t, field=True) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-t**2 - 3/(2*x)*t + 1/(2*x), t)]}) + assert splitfactor(p, DE) == (Poly(4*x**4*t**3 + (-8*x**3 - 4*x**4)*t**2 + + (4*x**2 + 8*x**3)*t - 4*x**2, t, domain='ZZ(x)'), + Poly(t**2 + 1/x*t + (1 - 2*x)/(4*x**2), t, domain='ZZ(x)')) + assert splitfactor(Poly(x, t), DE) == (Poly(x, t), Poly(1, t)) + r = Poly(-4*x**4*z**2 + 4*x**6*z**2 - z*x**3 - 4*x**5*z**3 + 4*x**3*z**3 + x**4 + z*x**5 - x**6, t) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + assert splitfactor(r, DE, coefficientD=True) == \ + (Poly(x*z - x**2 - z*x**3 + x**4, t), Poly(-x**2 + 4*x**2*z**2, t)) + assert splitfactor_sqf(r, DE, coefficientD=True) == \ + (((Poly(x*z - x**2 - z*x**3 + x**4, t), 1),), ((Poly(-x**2 + 4*x**2*z**2, t), 1),)) + assert splitfactor(Poly(0, t), DE) == (Poly(0, t), Poly(1, t)) + assert splitfactor_sqf(Poly(0, t), DE) == (((Poly(0, t), 1),), ()) + + +def test_canonical_representation(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t**2, t)]}) + assert canonical_representation(Poly(x - t, t), Poly(t**2, t), DE) == \ + (Poly(0, t, domain='ZZ[x]'), (Poly(0, t, domain='QQ[x]'), + Poly(1, t, domain='ZZ')), (Poly(-t + x, t, domain='QQ[x]'), + Poly(t**2, t))) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + assert canonical_representation(Poly(t**5 + t**3 + x**2*t + 1, t), + Poly((t**2 + 1)**3, t), DE) == \ + (Poly(0, t, domain='ZZ[x]'), (Poly(t**5 + t**3 + x**2*t + 1, t, domain='QQ[x]'), + Poly(t**6 + 3*t**4 + 3*t**2 + 1, t, domain='QQ')), + (Poly(0, t, domain='QQ[x]'), Poly(1, t, domain='QQ'))) + + +def test_hermite_reduce(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + + assert hermite_reduce(Poly(x - t, t), Poly(t**2, t), DE) == \ + ((Poly(-x, t, domain='QQ[x]'), Poly(t, t, domain='QQ[x]')), + (Poly(0, t, domain='QQ[x]'), Poly(1, t, domain='QQ[x]')), + (Poly(-x, t, domain='QQ[x]'), Poly(1, t, domain='QQ[x]'))) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-t**2 - t/x - (1 - nu**2/x**2), t)]}) + + assert hermite_reduce( + Poly(x**2*t**5 + x*t**4 - nu**2*t**3 - x*(x**2 + 1)*t**2 - (x**2 - nu**2)*t - x**5/4, t), + Poly(x**2*t**4 + x**2*(x**2 + 2)*t**2 + x**2 + x**4 + x**6/4, t), DE) == \ + ((Poly(-x**2 - 4, t, domain='ZZ(x,nu)'), Poly(4*t**2 + 2*x**2 + 4, t, domain='ZZ(x,nu)')), + (Poly((-2*nu**2 - x**4)*t - (2*x**3 + 2*x), t, domain='ZZ(x,nu)'), + Poly(2*x**2*t**2 + x**4 + 2*x**2, t, domain='ZZ(x,nu)')), + (Poly(x*t + 1, t, domain='ZZ(x,nu)'), Poly(x, t, domain='ZZ(x,nu)'))) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + + a = Poly((-2 + 3*x)*t**3 + (-1 + x)*t**2 + (-4*x + 2*x**2)*t + x**2, t) + d = Poly(x*t**6 - 4*x**2*t**5 + 6*x**3*t**4 - 4*x**4*t**3 + x**5*t**2, t) + + assert hermite_reduce(a, d, DE) == \ + ((Poly(3*t**2 + t + 3*x, t, domain='ZZ(x)'), + Poly(3*t**4 - 9*x*t**3 + 9*x**2*t**2 - 3*x**3*t, t, domain='ZZ(x)')), + (Poly(0, t, domain='ZZ(x)'), Poly(1, t, domain='ZZ(x)')), + (Poly(0, t, domain='ZZ(x)'), Poly(1, t, domain='ZZ(x)'))) + + assert hermite_reduce( + Poly(-t**2 + 2*t + 2, t, domain='ZZ(x)'), + Poly(-x*t**2 + 2*x*t - x, t, domain='ZZ(x)'), DE) == \ + ((Poly(3, t, domain='ZZ(x)'), Poly(t - 1, t, domain='ZZ(x)')), + (Poly(0, t, domain='ZZ(x)'), Poly(1, t, domain='ZZ(x)')), + (Poly(1, t, domain='ZZ(x)'), Poly(x, t, domain='ZZ(x)'))) + + assert hermite_reduce( + Poly(-x**2*t**6 + (-1 - 2*x**3 + x**4)*t**3 + (-3 - 3*x**4)*t**2 - + 2*x*t - x - 3*x**2, t, domain='ZZ(x)'), + Poly(x**4*t**6 - 2*x**2*t**3 + 1, t, domain='ZZ(x)'), DE) == \ + ((Poly(x**3*t + x**4 + 1, t, domain='ZZ(x)'), Poly(x**3*t**3 - x, t, domain='ZZ(x)')), + (Poly(0, t, domain='ZZ(x)'), Poly(1, t, domain='ZZ(x)')), + (Poly(-1, t, domain='ZZ(x)'), Poly(x**2, t, domain='ZZ(x)'))) + + assert hermite_reduce( + Poly((-2 + 3*x)*t**3 + (-1 + x)*t**2 + (-4*x + 2*x**2)*t + x**2, t), + Poly(x*t**6 - 4*x**2*t**5 + 6*x**3*t**4 - 4*x**4*t**3 + x**5*t**2, t), DE) == \ + ((Poly(3*t**2 + t + 3*x, t, domain='ZZ(x)'), + Poly(3*t**4 - 9*x*t**3 + 9*x**2*t**2 - 3*x**3*t, t, domain='ZZ(x)')), + (Poly(0, t, domain='ZZ(x)'), Poly(1, t, domain='ZZ(x)')), + (Poly(0, t, domain='ZZ(x)'), Poly(1, t, domain='ZZ(x)'))) + + +def test_polynomial_reduce(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t**2, t)]}) + assert polynomial_reduce(Poly(1 + x*t + t**2, t), DE) == \ + (Poly(t, t), Poly(x*t, t)) + assert polynomial_reduce(Poly(0, t), DE) == \ + (Poly(0, t), Poly(0, t)) + + +def test_laurent_series(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1, t)]}) + a = Poly(36, t) + d = Poly((t - 2)*(t**2 - 1)**2, t) + F = Poly(t**2 - 1, t) + n = 2 + assert laurent_series(a, d, F, n, DE) == \ + (Poly(-3*t**3 + 3*t**2 - 6*t - 8, t), Poly(t**5 + t**4 - 2*t**3 - 2*t**2 + t + 1, t), + [Poly(-3*t**3 - 6*t**2, t, domain='QQ'), Poly(2*t**6 + 6*t**5 - 8*t**3, t, domain='QQ')]) + + +def test_recognize_derivative(): + DE = DifferentialExtension(extension={'D': [Poly(1, t)]}) + a = Poly(36, t) + d = Poly((t - 2)*(t**2 - 1)**2, t) + assert recognize_derivative(a, d, DE) == False + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + a = Poly(2, t) + d = Poly(t**2 - 1, t) + assert recognize_derivative(a, d, DE) == False + assert recognize_derivative(Poly(x*t, t), Poly(1, t), DE) == True + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + assert recognize_derivative(Poly(t, t), Poly(1, t), DE) == True + + +def test_recognize_log_derivative(): + + a = Poly(2*x**2 + 4*x*t - 2*t - x**2*t, t) + d = Poly((2*x + t)*(t + x**2), t) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert recognize_log_derivative(a, d, DE, z) == True + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) + assert recognize_log_derivative(Poly(t + 1, t), Poly(t + x, t), DE) == True + assert recognize_log_derivative(Poly(2, t), Poly(t**2 - 1, t), DE) == True + DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) + assert recognize_log_derivative(Poly(1, x), Poly(x**2 - 2, x), DE) == False + assert recognize_log_derivative(Poly(1, x), Poly(x**2 + x, x), DE) == True + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + assert recognize_log_derivative(Poly(1, t), Poly(t**2 - 2, t), DE) == False + assert recognize_log_derivative(Poly(1, t), Poly(t**2 + t, t), DE) == False + + +def test_residue_reduce(): + a = Poly(2*t**2 - t - x**2, t) + d = Poly(t**3 - x**2*t, t) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)], 'Tfuncs': [log]}) + assert residue_reduce(a, d, DE, z, invert=False) == \ + ([(Poly(z**2 - Rational(1, 4), z, domain='ZZ(x)'), + Poly((1 + 3*x*z - 6*z**2 - 2*x**2 + 4*x**2*z**2)*t - x*z + x**2 + + 2*x**2*z**2 - 2*z*x**3, t, domain='ZZ(z, x)'))], False) + assert residue_reduce(a, d, DE, z, invert=True) == \ + ([(Poly(z**2 - Rational(1, 4), z, domain='ZZ(x)'), Poly(t + 2*x*z, t))], False) + assert residue_reduce(Poly(-2/x, t), Poly(t**2 - 1, t,), DE, z, invert=False) == \ + ([(Poly(z**2 - 1, z, domain='QQ'), Poly(-2*z*t/x - 2/x, t, domain='ZZ(z,x)'))], True) + ans = residue_reduce(Poly(-2/x, t), Poly(t**2 - 1, t), DE, z, invert=True) + assert ans == ([(Poly(z**2 - 1, z, domain='QQ'), Poly(t + z, t))], True) + assert residue_reduce_to_basic(ans[0], DE, z) == -log(-1 + log(x)) + log(1 + log(x)) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-t**2 - t/x - (1 - nu**2/x**2), t)]}) + # TODO: Skip or make faster + assert residue_reduce(Poly((-2*nu**2 - x**4)/(2*x**2)*t - (1 + x**2)/x, t), + Poly(t**2 + 1 + x**2/2, t), DE, z) == \ + ([(Poly(z + S.Half, z, domain='QQ'), Poly(t**2 + 1 + x**2/2, t, + domain='ZZ(x,nu)'))], True) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t**2, t)]}) + assert residue_reduce(Poly(-2*x*t + 1 - x**2, t), + Poly(t**2 + 2*x*t + 1 + x**2, t), DE, z) == \ + ([(Poly(z**2 + Rational(1, 4), z), Poly(t + x + 2*z, t))], True) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert residue_reduce(Poly(t, t), Poly(t + sqrt(2), t), DE, z) == \ + ([(Poly(z - 1, z, domain='QQ'), Poly(t + sqrt(2), t))], True) + + +def test_integrate_hyperexponential(): + # TODO: Add tests for integrate_hyperexponential() from the book + a = Poly((1 + 2*t1 + t1**2 + 2*t1**3)*t**2 + (1 + t1**2)*t + 1 + t1**2, t) + d = Poly(1, t) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t1**2, t1), + Poly(t*(1 + t1**2), t)], 'Tfuncs': [tan, Lambda(i, exp(tan(i)))]}) + assert integrate_hyperexponential(a, d, DE) == \ + (exp(2*tan(x))*tan(x) + exp(tan(x)), 1 + t1**2, True) + a = Poly((t1**3 + (x + 1)*t1**2 + t1 + x + 2)*t, t) + assert integrate_hyperexponential(a, d, DE) == \ + ((x + tan(x))*exp(tan(x)), 0, True) + + a = Poly(t, t) + d = Poly(1, t) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(2*x*t, t)], + 'Tfuncs': [Lambda(i, exp(x**2))]}) + + assert integrate_hyperexponential(a, d, DE) == \ + (0, NonElementaryIntegral(exp(x**2), x), False) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)], 'Tfuncs': [exp]}) + assert integrate_hyperexponential(a, d, DE) == (exp(x), 0, True) + + a = Poly(25*t**6 - 10*t**5 + 7*t**4 - 8*t**3 + 13*t**2 + 2*t - 1, t) + d = Poly(25*t**6 + 35*t**4 + 11*t**2 + 1, t) + assert integrate_hyperexponential(a, d, DE) == \ + (-(11 - 10*exp(x))/(5 + 25*exp(2*x)) + log(1 + exp(2*x)), -1, True) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t0, t0), Poly(t0*t, t)], + 'Tfuncs': [exp, Lambda(i, exp(exp(i)))]}) + assert integrate_hyperexponential(Poly(2*t0*t**2, t), Poly(1, t), DE) == (exp(2*exp(x)), 0, True) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t0, t0), Poly(-t0*t, t)], + 'Tfuncs': [exp, Lambda(i, exp(-exp(i)))]}) + assert integrate_hyperexponential(Poly(-27*exp(9) - 162*t0*exp(9) + + 27*x*t0*exp(9), t), Poly((36*exp(18) + x**2*exp(18) - 12*x*exp(18))*t, t), DE) == \ + (27*exp(exp(x))/(-6*exp(9) + x*exp(9)), 0, True) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)], 'Tfuncs': [exp]}) + assert integrate_hyperexponential(Poly(x**2/2*t, t), Poly(1, t), DE) == \ + ((2 - 2*x + x**2)*exp(x)/2, 0, True) + assert integrate_hyperexponential(Poly(1 + t, t), Poly(t, t), DE) == \ + (-exp(-x), 1, True) # x - exp(-x) + assert integrate_hyperexponential(Poly(x, t), Poly(t + 1, t), DE) == \ + (0, NonElementaryIntegral(x/(1 + exp(x)), x), False) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t0), Poly(2*x*t1, t1)], + 'Tfuncs': [log, Lambda(i, exp(i**2))]}) + + elem, nonelem, b = integrate_hyperexponential(Poly((8*x**7 - 12*x**5 + 6*x**3 - x)*t1**4 + + (8*t0*x**7 - 8*t0*x**6 - 4*t0*x**5 + 2*t0*x**3 + 2*t0*x**2 - t0*x + + 24*x**8 - 36*x**6 - 4*x**5 + 22*x**4 + 4*x**3 - 7*x**2 - x + 1)*t1**3 + + (8*t0*x**8 - 4*t0*x**6 - 16*t0*x**5 - 2*t0*x**4 + 12*t0*x**3 + + t0*x**2 - 2*t0*x + 24*x**9 - 36*x**7 - 8*x**6 + 22*x**5 + 12*x**4 - + 7*x**3 - 6*x**2 + x + 1)*t1**2 + (8*t0*x**8 - 8*t0*x**6 - 16*t0*x**5 + + 6*t0*x**4 + 10*t0*x**3 - 2*t0*x**2 - t0*x + 8*x**10 - 12*x**8 - 4*x**7 + + 2*x**6 + 12*x**5 + 3*x**4 - 9*x**3 - x**2 + 2*x)*t1 + 8*t0*x**7 - + 12*t0*x**6 - 4*t0*x**5 + 8*t0*x**4 - t0*x**2 - 4*x**7 + 4*x**6 + + 4*x**5 - 4*x**4 - x**3 + x**2, t1), Poly((8*x**7 - 12*x**5 + 6*x**3 - + x)*t1**4 + (24*x**8 + 8*x**7 - 36*x**6 - 12*x**5 + 18*x**4 + 6*x**3 - + 3*x**2 - x)*t1**3 + (24*x**9 + 24*x**8 - 36*x**7 - 36*x**6 + 18*x**5 + + 18*x**4 - 3*x**3 - 3*x**2)*t1**2 + (8*x**10 + 24*x**9 - 12*x**8 - + 36*x**7 + 6*x**6 + 18*x**5 - x**4 - 3*x**3)*t1 + 8*x**10 - 12*x**8 + + 6*x**6 - x**4, t1), DE) + + assert factor(elem) == -((x - 1)*log(x)/((x + exp(x**2))*(2*x**2 - 1))) + assert (nonelem, b) == (NonElementaryIntegral(exp(x**2)/(exp(x**2) + 1), x), False) + +def test_integrate_hyperexponential_polynomial(): + # Without proper cancellation within integrate_hyperexponential_polynomial(), + # this will take a long time to complete, and will return a complicated + # expression + p = Poly((-28*x**11*t0 - 6*x**8*t0 + 6*x**9*t0 - 15*x**8*t0**2 + + 15*x**7*t0**2 + 84*x**10*t0**2 - 140*x**9*t0**3 - 20*x**6*t0**3 + + 20*x**7*t0**3 - 15*x**6*t0**4 + 15*x**5*t0**4 + 140*x**8*t0**4 - + 84*x**7*t0**5 - 6*x**4*t0**5 + 6*x**5*t0**5 + x**3*t0**6 - x**4*t0**6 + + 28*x**6*t0**6 - 4*x**5*t0**7 + x**9 - x**10 + 4*x**12)/(-8*x**11*t0 + + 28*x**10*t0**2 - 56*x**9*t0**3 + 70*x**8*t0**4 - 56*x**7*t0**5 + + 28*x**6*t0**6 - 8*x**5*t0**7 + x**4*t0**8 + x**12)*t1**2 + + (-28*x**11*t0 - 12*x**8*t0 + 12*x**9*t0 - 30*x**8*t0**2 + + 30*x**7*t0**2 + 84*x**10*t0**2 - 140*x**9*t0**3 - 40*x**6*t0**3 + + 40*x**7*t0**3 - 30*x**6*t0**4 + 30*x**5*t0**4 + 140*x**8*t0**4 - + 84*x**7*t0**5 - 12*x**4*t0**5 + 12*x**5*t0**5 - 2*x**4*t0**6 + + 2*x**3*t0**6 + 28*x**6*t0**6 - 4*x**5*t0**7 + 2*x**9 - 2*x**10 + + 4*x**12)/(-8*x**11*t0 + 28*x**10*t0**2 - 56*x**9*t0**3 + + 70*x**8*t0**4 - 56*x**7*t0**5 + 28*x**6*t0**6 - 8*x**5*t0**7 + + x**4*t0**8 + x**12)*t1 + (-2*x**2*t0 + 2*x**3*t0 + x*t0**2 - + x**2*t0**2 + x**3 - x**4)/(-4*x**5*t0 + 6*x**4*t0**2 - 4*x**3*t0**3 + + x**2*t0**4 + x**6), t1, z, expand=False) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t0), Poly(2*x*t1, t1)]}) + assert integrate_hyperexponential_polynomial(p, DE, z) == ( + Poly((x - t0)*t1**2 + (-2*t0 + 2*x)*t1, t1), Poly(-2*x*t0 + x**2 + + t0**2, t1), True) + + DE = DifferentialExtension(extension={'D':[Poly(1, x), Poly(t0, t0)]}) + assert integrate_hyperexponential_polynomial(Poly(0, t0), DE, z) == ( + Poly(0, t0), Poly(1, t0), True) + + +def test_integrate_hyperexponential_returns_piecewise(): + a, b = symbols('a b') + DE = DifferentialExtension(a**x, x) + assert integrate_hyperexponential(DE.fa, DE.fd, DE) == (Piecewise( + (exp(x*log(a))/log(a), Ne(log(a), 0)), (x, True)), 0, True) + DE = DifferentialExtension(a**(b*x), x) + assert integrate_hyperexponential(DE.fa, DE.fd, DE) == (Piecewise( + (exp(b*x*log(a))/(b*log(a)), Ne(b*log(a), 0)), (x, True)), 0, True) + DE = DifferentialExtension(exp(a*x), x) + assert integrate_hyperexponential(DE.fa, DE.fd, DE) == (Piecewise( + (exp(a*x)/a, Ne(a, 0)), (x, True)), 0, True) + DE = DifferentialExtension(x*exp(a*x), x) + assert integrate_hyperexponential(DE.fa, DE.fd, DE) == (Piecewise( + ((a*x - 1)*exp(a*x)/a**2, Ne(a**2, 0)), (x**2/2, True)), 0, True) + DE = DifferentialExtension(x**2*exp(a*x), x) + assert integrate_hyperexponential(DE.fa, DE.fd, DE) == (Piecewise( + ((x**2*a**2 - 2*a*x + 2)*exp(a*x)/a**3, Ne(a**3, 0)), + (x**3/3, True)), 0, True) + DE = DifferentialExtension(x**y + z, y) + assert integrate_hyperexponential(DE.fa, DE.fd, DE) == (Piecewise( + (exp(log(x)*y)/log(x), Ne(log(x), 0)), (y, True)), z, True) + DE = DifferentialExtension(x**y + z + x**(2*y), y) + assert integrate_hyperexponential(DE.fa, DE.fd, DE) == (Piecewise( + ((exp(2*log(x)*y)*log(x) + + 2*exp(log(x)*y)*log(x))/(2*log(x)**2), Ne(2*log(x)**2, 0)), + (2*y, True), + ), z, True) + # TODO: Add a test where two different parts of the extension use a + # Piecewise, like y**x + z**x. + + +def test_issue_13947(): + a, t, s = symbols('a t s') + assert risch_integrate(2**(-pi)/(2**t + 1), t) == \ + 2**(-pi)*t - 2**(-pi)*log(2**t + 1)/log(2) + assert risch_integrate(a**(t - s)/(a**t + 1), t) == \ + exp(-s*log(a))*log(a**t + 1)/log(a) + + +def test_integrate_primitive(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)], + 'Tfuncs': [log]}) + assert integrate_primitive(Poly(t, t), Poly(1, t), DE) == (x*log(x), -1, True) + assert integrate_primitive(Poly(x, t), Poly(t, t), DE) == (0, NonElementaryIntegral(x/log(x), x), False) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t1), Poly(1/(x + 1), t2)], + 'Tfuncs': [log, Lambda(i, log(i + 1))]}) + assert integrate_primitive(Poly(t1, t2), Poly(t2, t2), DE) == \ + (0, NonElementaryIntegral(log(x)/log(1 + x), x), False) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t1), Poly(1/(x*t1), t2)], + 'Tfuncs': [log, Lambda(i, log(log(i)))]}) + assert integrate_primitive(Poly(t2, t2), Poly(t1, t2), DE) == \ + (0, NonElementaryIntegral(log(log(x))/log(x), x), False) + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t0)], + 'Tfuncs': [log]}) + assert integrate_primitive(Poly(x**2*t0**3 + (3*x**2 + x)*t0**2 + (3*x**2 + + 2*x)*t0 + x**2 + x, t0), Poly(x**2*t0**4 + 4*x**2*t0**3 + 6*x**2*t0**2 + + 4*x**2*t0 + x**2, t0), DE) == \ + (-1/(log(x) + 1), NonElementaryIntegral(1/(log(x) + 1), x), False) + +def test_integrate_hypertangent_polynomial(): + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**2 + 1, t)]}) + assert integrate_hypertangent_polynomial(Poly(t**2 + x*t + 1, t), DE) == \ + (Poly(t, t), Poly(x/2, t)) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(a*(t**2 + 1), t)]}) + assert integrate_hypertangent_polynomial(Poly(t**5, t), DE) == \ + (Poly(1/(4*a)*t**4 - 1/(2*a)*t**2, t), Poly(1/(2*a), t)) + + +def test_integrate_nonlinear_no_specials(): + a, d, = Poly(x**2*t**5 + x*t**4 - nu**2*t**3 - x*(x**2 + 1)*t**2 - (x**2 - + nu**2)*t - x**5/4, t), Poly(x**2*t**4 + x**2*(x**2 + 2)*t**2 + x**2 + x**4 + x**6/4, t) + # f(x) == phi_nu(x), the logarithmic derivative of J_v, the Bessel function, + # which has no specials (see Chapter 5, note 4 of Bronstein's book). + f = Function('phi_nu') + DE = DifferentialExtension(extension={'D': [Poly(1, x), + Poly(-t**2 - t/x - (1 - nu**2/x**2), t)], 'Tfuncs': [f]}) + assert integrate_nonlinear_no_specials(a, d, DE) == \ + (-log(1 + f(x)**2 + x**2/2)/2 + (- 4 - x**2)/(4 + 2*x**2 + 4*f(x)**2), True) + assert integrate_nonlinear_no_specials(Poly(t, t), Poly(1, t), DE) == \ + (0, False) + + +def test_integer_powers(): + assert integer_powers([x, x/2, x**2 + 1, x*Rational(2, 3)]) == [ + (x/6, [(x, 6), (x/2, 3), (x*Rational(2, 3), 4)]), + (1 + x**2, [(1 + x**2, 1)])] + + +def test_DifferentialExtension_exp(): + assert DifferentialExtension(exp(x) + exp(x**2), x)._important_attrs == \ + (Poly(t1 + t0, t1), Poly(1, t1), [Poly(1, x,), Poly(t0, t0), + Poly(2*x*t1, t1)], [x, t0, t1], [Lambda(i, exp(i)), + Lambda(i, exp(i**2))], [], [None, 'exp', 'exp'], [None, x, x**2]) + assert DifferentialExtension(exp(x) + exp(2*x), x)._important_attrs == \ + (Poly(t0**2 + t0, t0), Poly(1, t0), [Poly(1, x), Poly(t0, t0)], [x, t0], + [Lambda(i, exp(i))], [], [None, 'exp'], [None, x]) + assert DifferentialExtension(exp(x) + exp(x/2), x)._important_attrs == \ + (Poly(t0**2 + t0, t0), Poly(1, t0), [Poly(1, x), Poly(t0/2, t0)], + [x, t0], [Lambda(i, exp(i/2))], [], [None, 'exp'], [None, x/2]) + assert DifferentialExtension(exp(x) + exp(x**2) + exp(x + x**2), x)._important_attrs == \ + (Poly((1 + t0)*t1 + t0, t1), Poly(1, t1), [Poly(1, x), Poly(t0, t0), + Poly(2*x*t1, t1)], [x, t0, t1], [Lambda(i, exp(i)), + Lambda(i, exp(i**2))], [], [None, 'exp', 'exp'], [None, x, x**2]) + assert DifferentialExtension(exp(x) + exp(x**2) + exp(x + x**2 + 1), x)._important_attrs == \ + (Poly((1 + S.Exp1*t0)*t1 + t0, t1), Poly(1, t1), [Poly(1, x), + Poly(t0, t0), Poly(2*x*t1, t1)], [x, t0, t1], [Lambda(i, exp(i)), + Lambda(i, exp(i**2))], [], [None, 'exp', 'exp'], [None, x, x**2]) + assert DifferentialExtension(exp(x) + exp(x**2) + exp(x/2 + x**2), x)._important_attrs == \ + (Poly((t0 + 1)*t1 + t0**2, t1), Poly(1, t1), [Poly(1, x), + Poly(t0/2, t0), Poly(2*x*t1, t1)], [x, t0, t1], + [Lambda(i, exp(i/2)), Lambda(i, exp(i**2))], + [(exp(x/2), sqrt(exp(x)))], [None, 'exp', 'exp'], [None, x/2, x**2]) + assert DifferentialExtension(exp(x) + exp(x**2) + exp(x/2 + x**2 + 3), x)._important_attrs == \ + (Poly((t0*exp(3) + 1)*t1 + t0**2, t1), Poly(1, t1), [Poly(1, x), + Poly(t0/2, t0), Poly(2*x*t1, t1)], [x, t0, t1], [Lambda(i, exp(i/2)), + Lambda(i, exp(i**2))], [(exp(x/2), sqrt(exp(x)))], [None, 'exp', 'exp'], + [None, x/2, x**2]) + assert DifferentialExtension(sqrt(exp(x)), x)._important_attrs == \ + (Poly(t0, t0), Poly(1, t0), [Poly(1, x), Poly(t0/2, t0)], [x, t0], + [Lambda(i, exp(i/2))], [(exp(x/2), sqrt(exp(x)))], [None, 'exp'], [None, x/2]) + + assert DifferentialExtension(exp(x/2), x)._important_attrs == \ + (Poly(t0, t0), Poly(1, t0), [Poly(1, x), Poly(t0/2, t0)], [x, t0], + [Lambda(i, exp(i/2))], [], [None, 'exp'], [None, x/2]) + + +def test_DifferentialExtension_log(): + assert DifferentialExtension(log(x)*log(x + 1)*log(2*x**2 + 2*x), x)._important_attrs == \ + (Poly(t0*t1**2 + (t0*log(2) + t0**2)*t1, t1), Poly(1, t1), + [Poly(1, x), Poly(1/x, t0), + Poly(1/(x + 1), t1, expand=False)], [x, t0, t1], + [Lambda(i, log(i)), Lambda(i, log(i + 1))], [], [None, 'log', 'log'], + [None, x, x + 1]) + assert DifferentialExtension(x**x*log(x), x)._important_attrs == \ + (Poly(t0*t1, t1), Poly(1, t1), [Poly(1, x), Poly(1/x, t0), + Poly((1 + t0)*t1, t1)], [x, t0, t1], [Lambda(i, log(i)), + Lambda(i, exp(t0*i))], [(exp(x*log(x)), x**x)], [None, 'log', 'exp'], + [None, x, t0*x]) + + +def test_DifferentialExtension_symlog(): + # See comment on test_risch_integrate below + assert DifferentialExtension(log(x**x), x)._important_attrs == \ + (Poly(t0*x, t1), Poly(1, t1), [Poly(1, x), Poly(1/x, t0), Poly((t0 + + 1)*t1, t1)], [x, t0, t1], [Lambda(i, log(i)), Lambda(i, exp(i*t0))], + [(exp(x*log(x)), x**x)], [None, 'log', 'exp'], [None, x, t0*x]) + assert DifferentialExtension(log(x**y), x)._important_attrs == \ + (Poly(y*t0, t0), Poly(1, t0), [Poly(1, x), Poly(1/x, t0)], [x, t0], + [Lambda(i, log(i))], [(y*log(x), log(x**y))], [None, 'log'], + [None, x]) + assert DifferentialExtension(log(sqrt(x)), x)._important_attrs == \ + (Poly(t0, t0), Poly(2, t0), [Poly(1, x), Poly(1/x, t0)], [x, t0], + [Lambda(i, log(i))], [(log(x)/2, log(sqrt(x)))], [None, 'log'], + [None, x]) + + +def test_DifferentialExtension_handle_first(): + assert DifferentialExtension(exp(x)*log(x), x, handle_first='log')._important_attrs == \ + (Poly(t0*t1, t1), Poly(1, t1), [Poly(1, x), Poly(1/x, t0), + Poly(t1, t1)], [x, t0, t1], [Lambda(i, log(i)), Lambda(i, exp(i))], + [], [None, 'log', 'exp'], [None, x, x]) + assert DifferentialExtension(exp(x)*log(x), x, handle_first='exp')._important_attrs == \ + (Poly(t0*t1, t1), Poly(1, t1), [Poly(1, x), Poly(t0, t0), + Poly(1/x, t1)], [x, t0, t1], [Lambda(i, exp(i)), Lambda(i, log(i))], + [], [None, 'exp', 'log'], [None, x, x]) + + # This one must have the log first, regardless of what we set it to + # (because the log is inside of the exponential: x**x == exp(x*log(x))) + assert DifferentialExtension(-x**x*log(x)**2 + x**x - x**x/x, x, + handle_first='exp')._important_attrs == \ + DifferentialExtension(-x**x*log(x)**2 + x**x - x**x/x, x, + handle_first='log')._important_attrs == \ + (Poly((-1 + x - x*t0**2)*t1, t1), Poly(x, t1), + [Poly(1, x), Poly(1/x, t0), Poly((1 + t0)*t1, t1)], [x, t0, t1], + [Lambda(i, log(i)), Lambda(i, exp(t0*i))], [(exp(x*log(x)), x**x)], + [None, 'log', 'exp'], [None, x, t0*x]) + + +def test_DifferentialExtension_all_attrs(): + # Test 'unimportant' attributes + DE = DifferentialExtension(exp(x)*log(x), x, handle_first='exp') + assert DE.f == exp(x)*log(x) + assert DE.newf == t0*t1 + assert DE.x == x + assert DE.cases == ['base', 'exp', 'primitive'] + assert DE.case == 'primitive' + + assert DE.level == -1 + assert DE.t == t1 == DE.T[DE.level] + assert DE.d == Poly(1/x, t1) == DE.D[DE.level] + raises(ValueError, lambda: DE.increment_level()) + DE.decrement_level() + assert DE.level == -2 + assert DE.t == t0 == DE.T[DE.level] + assert DE.d == Poly(t0, t0) == DE.D[DE.level] + assert DE.case == 'exp' + DE.decrement_level() + assert DE.level == -3 + assert DE.t == x == DE.T[DE.level] == DE.x + assert DE.d == Poly(1, x) == DE.D[DE.level] + assert DE.case == 'base' + raises(ValueError, lambda: DE.decrement_level()) + DE.increment_level() + DE.increment_level() + assert DE.level == -1 + assert DE.t == t1 == DE.T[DE.level] + assert DE.d == Poly(1/x, t1) == DE.D[DE.level] + assert DE.case == 'primitive' + + # Test methods + assert DE.indices('log') == [2] + assert DE.indices('exp') == [1] + + +def test_DifferentialExtension_extension_flag(): + raises(ValueError, lambda: DifferentialExtension(extension={'T': [x, t]})) + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) + assert DE._important_attrs == (None, None, [Poly(1, x), Poly(t, t)], [x, t], + None, None, None, None) + assert DE.d == Poly(t, t) + assert DE.t == t + assert DE.level == -1 + assert DE.cases == ['base', 'exp'] + assert DE.x == x + assert DE.case == 'exp' + + DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)], + 'exts': [None, 'exp'], 'extargs': [None, x]}) + assert DE._important_attrs == (None, None, [Poly(1, x), Poly(t, t)], [x, t], + None, None, [None, 'exp'], [None, x]) + raises(ValueError, lambda: DifferentialExtension()) + + +def test_DifferentialExtension_misc(): + # Odd ends + assert DifferentialExtension(sin(y)*exp(x), x)._important_attrs == \ + (Poly(sin(y)*t0, t0, domain='ZZ[sin(y)]'), Poly(1, t0, domain='ZZ'), + [Poly(1, x, domain='ZZ'), Poly(t0, t0, domain='ZZ')], [x, t0], + [Lambda(i, exp(i))], [], [None, 'exp'], [None, x]) + raises(NotImplementedError, lambda: DifferentialExtension(sin(x), x)) + assert DifferentialExtension(10**x, x)._important_attrs == \ + (Poly(t0, t0), Poly(1, t0), [Poly(1, x), Poly(log(10)*t0, t0)], [x, t0], + [Lambda(i, exp(i*log(10)))], [(exp(x*log(10)), 10**x)], [None, 'exp'], + [None, x*log(10)]) + assert DifferentialExtension(log(x) + log(x**2), x)._important_attrs in [ + (Poly(3*t0, t0), Poly(2, t0), [Poly(1, x), Poly(2/x, t0)], [x, t0], + [Lambda(i, log(i**2))], [], [None, ], [], [1], [x**2]), + (Poly(3*t0, t0), Poly(1, t0), [Poly(1, x), Poly(1/x, t0)], [x, t0], + [Lambda(i, log(i))], [], [None, 'log'], [None, x])] + assert DifferentialExtension(S.Zero, x)._important_attrs == \ + (Poly(0, x), Poly(1, x), [Poly(1, x)], [x], [], [], [None], [None]) + assert DifferentialExtension(tan(atan(x).rewrite(log)), x)._important_attrs == \ + (Poly(x, x), Poly(1, x), [Poly(1, x)], [x], [], [], [None], [None]) + + +def test_DifferentialExtension_Rothstein(): + # Rothstein's integral + f = (2581284541*exp(x) + 1757211400)/(39916800*exp(3*x) + + 119750400*exp(x)**2 + 119750400*exp(x) + 39916800)*exp(1/(exp(x) + 1) - 10*x) + assert DifferentialExtension(f, x)._important_attrs == \ + (Poly((1757211400 + 2581284541*t0)*t1, t1), Poly(39916800 + + 119750400*t0 + 119750400*t0**2 + 39916800*t0**3, t1), + [Poly(1, x), Poly(t0, t0), Poly(-(10 + 21*t0 + 10*t0**2)/(1 + 2*t0 + + t0**2)*t1, t1, domain='ZZ(t0)')], [x, t0, t1], + [Lambda(i, exp(i)), Lambda(i, exp(1/(t0 + 1) - 10*i))], [], + [None, 'exp', 'exp'], [None, x, 1/(t0 + 1) - 10*x]) + + +class _TestingException(Exception): + """Dummy Exception class for testing.""" + pass + + +def test_DecrementLevel(): + DE = DifferentialExtension(x*log(exp(x) + 1), x) + assert DE.level == -1 + assert DE.t == t1 + assert DE.d == Poly(t0/(t0 + 1), t1) + assert DE.case == 'primitive' + + with DecrementLevel(DE): + assert DE.level == -2 + assert DE.t == t0 + assert DE.d == Poly(t0, t0) + assert DE.case == 'exp' + + with DecrementLevel(DE): + assert DE.level == -3 + assert DE.t == x + assert DE.d == Poly(1, x) + assert DE.case == 'base' + + assert DE.level == -2 + assert DE.t == t0 + assert DE.d == Poly(t0, t0) + assert DE.case == 'exp' + + assert DE.level == -1 + assert DE.t == t1 + assert DE.d == Poly(t0/(t0 + 1), t1) + assert DE.case == 'primitive' + + # Test that __exit__ is called after an exception correctly + try: + with DecrementLevel(DE): + raise _TestingException + except _TestingException: + pass + else: + raise AssertionError("Did not raise.") + + assert DE.level == -1 + assert DE.t == t1 + assert DE.d == Poly(t0/(t0 + 1), t1) + assert DE.case == 'primitive' + + +def test_risch_integrate(): + assert risch_integrate(t0*exp(x), x) == t0*exp(x) + assert risch_integrate(sin(x), x, rewrite_complex=True) == -exp(I*x)/2 - exp(-I*x)/2 + + # From my GSoC writeup + assert risch_integrate((1 + 2*x**2 + x**4 + 2*x**3*exp(2*x**2))/ + (x**4*exp(x**2) + 2*x**2*exp(x**2) + exp(x**2)), x) == \ + NonElementaryIntegral(exp(-x**2), x) + exp(x**2)/(1 + x**2) + + + assert risch_integrate(0, x) == 0 + + # also tests prde_cancel() + e1 = log(x/exp(x) + 1) + ans1 = risch_integrate(e1, x) + assert ans1 == (x*log(x*exp(-x) + 1) + NonElementaryIntegral((x**2 - x)/(x + exp(x)), x)) + assert cancel(diff(ans1, x) - e1) == 0 + + # also tests issue #10798 + e2 = (log(-1/y)/2 - log(1/y)/2)/y - (log(1 - 1/y)/2 - log(1 + 1/y)/2)/y + ans2 = risch_integrate(e2, y) + assert ans2 == log(1/y)*log(1 - 1/y)/2 - log(1/y)*log(1 + 1/y)/2 + \ + NonElementaryIntegral((I*pi*y**2 - 2*y*log(1/y) - I*pi)/(2*y**3 - 2*y), y) + assert expand_log(cancel(diff(ans2, y) - e2), force=True) == 0 + + # These are tested here in addition to in test_DifferentialExtension above + # (symlogs) to test that backsubs works correctly. The integrals should be + # written in terms of the original logarithms in the integrands. + + # XXX: Unfortunately, making backsubs work on this one is a little + # trickier, because x**x is converted to exp(x*log(x)), and so log(x**x) + # is converted to x*log(x). (x**2*log(x)).subs(x*log(x), log(x**x)) is + # smart enough, the issue is that these splits happen at different places + # in the algorithm. Maybe a heuristic is in order + assert risch_integrate(log(x**x), x) == x**2*log(x)/2 - x**2/4 + + assert risch_integrate(log(x**y), x) == x*log(x**y) - x*y + assert risch_integrate(log(sqrt(x)), x) == x*log(sqrt(x)) - x/2 + + +def test_risch_integrate_float(): + assert risch_integrate((-60*exp(x) - 19.2*exp(4*x))*exp(4*x), x) == -2.4*exp(8*x) - 12.0*exp(5*x) + + +def test_NonElementaryIntegral(): + assert isinstance(risch_integrate(exp(x**2), x), NonElementaryIntegral) + assert isinstance(risch_integrate(x**x*log(x), x), NonElementaryIntegral) + # Make sure methods of Integral still give back a NonElementaryIntegral + assert isinstance(NonElementaryIntegral(x**x*t0, x).subs(t0, log(x)), NonElementaryIntegral) + + +def test_xtothex(): + a = risch_integrate(x**x, x) + assert a == NonElementaryIntegral(x**x, x) + assert isinstance(a, NonElementaryIntegral) + + +def test_DifferentialExtension_equality(): + DE1 = DE2 = DifferentialExtension(log(x), x) + assert DE1 == DE2 + + +def test_DifferentialExtension_printing(): + DE = DifferentialExtension(exp(2*x**2) + log(exp(x**2) + 1), x) + assert repr(DE) == ("DifferentialExtension(dict([('f', exp(2*x**2) + log(exp(x**2) + 1)), " + "('x', x), ('T', [x, t0, t1]), ('D', [Poly(1, x, domain='ZZ'), Poly(2*x*t0, t0, domain='ZZ[x]'), " + "Poly(2*t0*x/(t0 + 1), t1, domain='ZZ(x,t0)')]), ('fa', Poly(t1 + t0**2, t1, domain='ZZ[t0]')), " + "('fd', Poly(1, t1, domain='ZZ')), ('Tfuncs', [Lambda(i, exp(i**2)), Lambda(i, log(t0 + 1))]), " + "('backsubs', []), ('exts', [None, 'exp', 'log']), ('extargs', [None, x**2, t0 + 1]), " + "('cases', ['base', 'exp', 'primitive']), ('case', 'primitive'), ('t', t1), " + "('d', Poly(2*t0*x/(t0 + 1), t1, domain='ZZ(x,t0)')), ('newf', t0**2 + t1), ('level', -1), " + "('dummy', False)]))") + + assert str(DE) == ("DifferentialExtension({fa=Poly(t1 + t0**2, t1, domain='ZZ[t0]'), " + "fd=Poly(1, t1, domain='ZZ'), D=[Poly(1, x, domain='ZZ'), Poly(2*x*t0, t0, domain='ZZ[x]'), " + "Poly(2*t0*x/(t0 + 1), t1, domain='ZZ(x,t0)')]})") + + +def test_issue_23948(): + f = ( + ( (-2*x**5 + 28*x**4 - 144*x**3 + 324*x**2 - 270*x)*log(x)**2 + +(-4*x**6 + 56*x**5 - 288*x**4 + 648*x**3 - 540*x**2)*log(x) + +(2*x**5 - 28*x**4 + 144*x**3 - 324*x**2 + 270*x)*exp(x) + +(2*x**5 - 28*x**4 + 144*x**3 - 324*x**2 + 270*x)*log(5) + -2*x**7 + 26*x**6 - 116*x**5 + 180*x**4 + 54*x**3 - 270*x**2 + )*log(-log(x)**2 - 2*x*log(x) + exp(x) + log(5) - x**2 - x)**2 + +( (4*x**5 - 44*x**4 + 168*x**3 - 216*x**2 - 108*x + 324)*log(x) + +(-2*x**5 + 24*x**4 - 108*x**3 + 216*x**2 - 162*x)*exp(x) + +4*x**6 - 42*x**5 + 144*x**4 - 108*x**3 - 324*x**2 + 486*x + )*log(-log(x)**2 - 2*x*log(x) + exp(x) + log(5) - x**2 - x) + )/(x*exp(x)**2*log(x)**2 + 2*x**2*exp(x)**2*log(x) - x*exp(x)**3 + +(-x*log(5) + x**3 + x**2)*exp(x)**2) + + F = ((x**4 - 12*x**3 + 54*x**2 - 108*x + 81)*exp(-2*x) + *log(-x**2 - 2*x*log(x) - x + exp(x) - log(x)**2 + log(5))**2) + + assert risch_integrate(f, x) == F diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_singularityfunctions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_singularityfunctions.py new file mode 100644 index 0000000000000000000000000000000000000000..587e5f104cbf095f851ec538601ca146377b51ae --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_singularityfunctions.py @@ -0,0 +1,22 @@ +from sympy.integrals.singularityfunctions import singularityintegrate +from sympy.core.function import Function +from sympy.core.symbol import symbols +from sympy.functions.special.singularity_functions import SingularityFunction + +x, a, n, y = symbols('x a n y') +f = Function('f') + + +def test_singularityintegrate(): + assert singularityintegrate(x, x) is None + assert singularityintegrate(x + SingularityFunction(x, 9, 1), x) is None + + assert 4*singularityintegrate(SingularityFunction(x, a, 3), x) == 4*SingularityFunction(x, a, 4)/4 + assert singularityintegrate(5*SingularityFunction(x, 5, -2), x) == 5*SingularityFunction(x, 5, -1) + assert singularityintegrate(6*SingularityFunction(x, 5, -1), x) == 6*SingularityFunction(x, 5, 0) + assert singularityintegrate(x*SingularityFunction(x, 0, -1), x) == 0 + assert singularityintegrate((x - 5)*SingularityFunction(x, 5, -1), x) == 0 + assert singularityintegrate(SingularityFunction(x, 0, -1) * f(x), x) == f(0) * SingularityFunction(x, 0, 0) + assert singularityintegrate(SingularityFunction(x, 1, -1) * f(x), x) == f(1) * SingularityFunction(x, 1, 0) + assert singularityintegrate(y*SingularityFunction(x, 0, -1)**2, x) == \ + y*SingularityFunction(0, 0, -1)*SingularityFunction(x, 0, 0) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_transforms.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_transforms.py new file mode 100644 index 0000000000000000000000000000000000000000..fdf7192594bad532c93ffb31e5b2f05cfd8970f1 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_transforms.py @@ -0,0 +1,637 @@ +from sympy.integrals.transforms import ( + mellin_transform, inverse_mellin_transform, + fourier_transform, inverse_fourier_transform, + sine_transform, inverse_sine_transform, + cosine_transform, inverse_cosine_transform, + hankel_transform, inverse_hankel_transform, + FourierTransform, SineTransform, CosineTransform, InverseFourierTransform, + InverseSineTransform, InverseCosineTransform, IntegralTransformError) +from sympy.integrals.laplace import ( + laplace_transform, inverse_laplace_transform) +from sympy.core.function import Function, expand_mul +from sympy.core import EulerGamma +from sympy.core.numbers import I, Rational, oo, pi +from sympy.core.singleton import S +from sympy.core.symbol import Symbol, symbols +from sympy.functions.combinatorial.factorials import factorial +from sympy.functions.elementary.complexes import re, unpolarify +from sympy.functions.elementary.exponential import exp, exp_polar, log +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.functions.elementary.trigonometric import atan, cos, sin, tan +from sympy.functions.special.bessel import besseli, besselj, besselk, bessely +from sympy.functions.special.delta_functions import Heaviside +from sympy.functions.special.error_functions import erf, expint +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import meijerg +from sympy.simplify.gammasimp import gammasimp +from sympy.simplify.hyperexpand import hyperexpand +from sympy.simplify.trigsimp import trigsimp +from sympy.testing.pytest import XFAIL, slow, skip, raises +from sympy.abc import x, s, a, b, c, d + + +nu, beta, rho = symbols('nu beta rho') + + +def test_undefined_function(): + from sympy.integrals.transforms import MellinTransform + f = Function('f') + assert mellin_transform(f(x), x, s) == MellinTransform(f(x), x, s) + assert mellin_transform(f(x) + exp(-x), x, s) == \ + (MellinTransform(f(x), x, s) + gamma(s + 1)/s, (0, oo), True) + + +def test_free_symbols(): + f = Function('f') + assert mellin_transform(f(x), x, s).free_symbols == {s} + assert mellin_transform(f(x)*a, x, s).free_symbols == {s, a} + + +def test_as_integral(): + from sympy.integrals.integrals import Integral + f = Function('f') + assert mellin_transform(f(x), x, s).rewrite('Integral') == \ + Integral(x**(s - 1)*f(x), (x, 0, oo)) + assert fourier_transform(f(x), x, s).rewrite('Integral') == \ + Integral(f(x)*exp(-2*I*pi*s*x), (x, -oo, oo)) + assert laplace_transform(f(x), x, s, noconds=True).rewrite('Integral') == \ + Integral(f(x)*exp(-s*x), (x, 0, oo)) + assert str(2*pi*I*inverse_mellin_transform(f(s), s, x, (a, b)).rewrite('Integral')) \ + == "Integral(f(s)/x**s, (s, _c - oo*I, _c + oo*I))" + assert str(2*pi*I*inverse_laplace_transform(f(s), s, x).rewrite('Integral')) == \ + "Integral(f(s)*exp(s*x), (s, _c - oo*I, _c + oo*I))" + assert inverse_fourier_transform(f(s), s, x).rewrite('Integral') == \ + Integral(f(s)*exp(2*I*pi*s*x), (s, -oo, oo)) + +# NOTE this is stuck in risch because meijerint cannot handle it + + +@slow +@XFAIL +def test_mellin_transform_fail(): + skip("Risch takes forever.") + + MT = mellin_transform + + bpos = symbols('b', positive=True) + # bneg = symbols('b', negative=True) + + expr = (sqrt(x + b**2) + b)**a/sqrt(x + b**2) + # TODO does not work with bneg, argument wrong. Needs changes to matching. + assert MT(expr.subs(b, -bpos), x, s) == \ + ((-1)**(a + 1)*2**(a + 2*s)*bpos**(a + 2*s - 1)*gamma(a + s) + *gamma(1 - a - 2*s)/gamma(1 - s), + (-re(a), -re(a)/2 + S.Half), True) + + expr = (sqrt(x + b**2) + b)**a + assert MT(expr.subs(b, -bpos), x, s) == \ + ( + 2**(a + 2*s)*a*bpos**(a + 2*s)*gamma(-a - 2* + s)*gamma(a + s)/gamma(-s + 1), + (-re(a), -re(a)/2), True) + + # Test exponent 1: + assert MT(expr.subs({b: -bpos, a: 1}), x, s) == \ + (-bpos**(2*s + 1)*gamma(s)*gamma(-s - S.Half)/(2*sqrt(pi)), + (-1, Rational(-1, 2)), True) + + +def test_mellin_transform(): + from sympy.functions.elementary.miscellaneous import (Max, Min) + MT = mellin_transform + + bpos = symbols('b', positive=True) + + # 8.4.2 + assert MT(x**nu*Heaviside(x - 1), x, s) == \ + (-1/(nu + s), (-oo, -re(nu)), True) + assert MT(x**nu*Heaviside(1 - x), x, s) == \ + (1/(nu + s), (-re(nu), oo), True) + + assert MT((1 - x)**(beta - 1)*Heaviside(1 - x), x, s) == \ + (gamma(beta)*gamma(s)/gamma(beta + s), (0, oo), re(beta) > 0) + assert MT((x - 1)**(beta - 1)*Heaviside(x - 1), x, s) == \ + (gamma(beta)*gamma(1 - beta - s)/gamma(1 - s), + (-oo, 1 - re(beta)), re(beta) > 0) + + assert MT((1 + x)**(-rho), x, s) == \ + (gamma(s)*gamma(rho - s)/gamma(rho), (0, re(rho)), True) + + assert MT(abs(1 - x)**(-rho), x, s) == ( + 2*sin(pi*rho/2)*gamma(1 - rho)* + cos(pi*(s - rho/2))*gamma(s)*gamma(rho-s)/pi, + (0, re(rho)), re(rho) < 1) + mt = MT((1 - x)**(beta - 1)*Heaviside(1 - x) + + a*(x - 1)**(beta - 1)*Heaviside(x - 1), x, s) + assert mt[1], mt[2] == ((0, -re(beta) + 1), re(beta) > 0) + + assert MT((x**a - b**a)/(x - b), x, s)[0] == \ + pi*b**(a + s - 1)*sin(pi*a)/(sin(pi*s)*sin(pi*(a + s))) + assert MT((x**a - bpos**a)/(x - bpos), x, s) == \ + (pi*bpos**(a + s - 1)*sin(pi*a)/(sin(pi*s)*sin(pi*(a + s))), + (Max(0, -re(a)), Min(1, 1 - re(a))), True) + + expr = (sqrt(x + b**2) + b)**a + assert MT(expr.subs(b, bpos), x, s) == \ + (-a*(2*bpos)**(a + 2*s)*gamma(s)*gamma(-a - 2*s)/gamma(-a - s + 1), + (0, -re(a)/2), True) + + expr = (sqrt(x + b**2) + b)**a/sqrt(x + b**2) + assert MT(expr.subs(b, bpos), x, s) == \ + (2**(a + 2*s)*bpos**(a + 2*s - 1)*gamma(s) + *gamma(1 - a - 2*s)/gamma(1 - a - s), + (0, -re(a)/2 + S.Half), True) + + # 8.4.2 + assert MT(exp(-x), x, s) == (gamma(s), (0, oo), True) + assert MT(exp(-1/x), x, s) == (gamma(-s), (-oo, 0), True) + + # 8.4.5 + assert MT(log(x)**4*Heaviside(1 - x), x, s) == (24/s**5, (0, oo), True) + assert MT(log(x)**3*Heaviside(x - 1), x, s) == (6/s**4, (-oo, 0), True) + assert MT(log(x + 1), x, s) == (pi/(s*sin(pi*s)), (-1, 0), True) + assert MT(log(1/x + 1), x, s) == (pi/(s*sin(pi*s)), (0, 1), True) + assert MT(log(abs(1 - x)), x, s) == (pi/(s*tan(pi*s)), (-1, 0), True) + assert MT(log(abs(1 - 1/x)), x, s) == (pi/(s*tan(pi*s)), (0, 1), True) + + # 8.4.14 + assert MT(erf(sqrt(x)), x, s) == \ + (-gamma(s + S.Half)/(sqrt(pi)*s), (Rational(-1, 2), 0), True) + + +def test_mellin_transform2(): + MT = mellin_transform + # TODO we cannot currently do these (needs summation of 3F2(-1)) + # this also implies that they cannot be written as a single g-function + # (although this is possible) + mt = MT(log(x)/(x + 1), x, s) + assert mt[1:] == ((0, 1), True) + assert not hyperexpand(mt[0], allow_hyper=True).has(meijerg) + mt = MT(log(x)**2/(x + 1), x, s) + assert mt[1:] == ((0, 1), True) + assert not hyperexpand(mt[0], allow_hyper=True).has(meijerg) + mt = MT(log(x)/(x + 1)**2, x, s) + assert mt[1:] == ((0, 2), True) + assert not hyperexpand(mt[0], allow_hyper=True).has(meijerg) + + +@slow +def test_mellin_transform_bessel(): + from sympy.functions.elementary.miscellaneous import Max + MT = mellin_transform + + # 8.4.19 + assert MT(besselj(a, 2*sqrt(x)), x, s) == \ + (gamma(a/2 + s)/gamma(a/2 - s + 1), (-re(a)/2, Rational(3, 4)), True) + assert MT(sin(sqrt(x))*besselj(a, sqrt(x)), x, s) == \ + (2**a*gamma(-2*s + S.Half)*gamma(a/2 + s + S.Half)/( + gamma(-a/2 - s + 1)*gamma(a - 2*s + 1)), ( + -re(a)/2 - S.Half, Rational(1, 4)), True) + assert MT(cos(sqrt(x))*besselj(a, sqrt(x)), x, s) == \ + (2**a*gamma(a/2 + s)*gamma(-2*s + S.Half)/( + gamma(-a/2 - s + S.Half)*gamma(a - 2*s + 1)), ( + -re(a)/2, Rational(1, 4)), True) + assert MT(besselj(a, sqrt(x))**2, x, s) == \ + (gamma(a + s)*gamma(S.Half - s) + / (sqrt(pi)*gamma(1 - s)*gamma(1 + a - s)), + (-re(a), S.Half), True) + assert MT(besselj(a, sqrt(x))*besselj(-a, sqrt(x)), x, s) == \ + (gamma(s)*gamma(S.Half - s) + / (sqrt(pi)*gamma(1 - a - s)*gamma(1 + a - s)), + (0, S.Half), True) + # NOTE: prudnikov gives the strip below as (1/2 - re(a), 1). As far as + # I can see this is wrong (since besselj(z) ~ 1/sqrt(z) for z large) + assert MT(besselj(a - 1, sqrt(x))*besselj(a, sqrt(x)), x, s) == \ + (gamma(1 - s)*gamma(a + s - S.Half) + / (sqrt(pi)*gamma(Rational(3, 2) - s)*gamma(a - s + S.Half)), + (S.Half - re(a), S.Half), True) + assert MT(besselj(a, sqrt(x))*besselj(b, sqrt(x)), x, s) == \ + (4**s*gamma(1 - 2*s)*gamma((a + b)/2 + s) + / (gamma(1 - s + (b - a)/2)*gamma(1 - s + (a - b)/2) + *gamma( 1 - s + (a + b)/2)), + (-(re(a) + re(b))/2, S.Half), True) + assert MT(besselj(a, sqrt(x))**2 + besselj(-a, sqrt(x))**2, x, s)[1:] == \ + ((Max(re(a), -re(a)), S.Half), True) + + # Section 8.4.20 + assert MT(bessely(a, 2*sqrt(x)), x, s) == \ + (-cos(pi*(a/2 - s))*gamma(s - a/2)*gamma(s + a/2)/pi, + (Max(-re(a)/2, re(a)/2), Rational(3, 4)), True) + assert MT(sin(sqrt(x))*bessely(a, sqrt(x)), x, s) == \ + (-4**s*sin(pi*(a/2 - s))*gamma(S.Half - 2*s) + * gamma((1 - a)/2 + s)*gamma((1 + a)/2 + s) + / (sqrt(pi)*gamma(1 - s - a/2)*gamma(1 - s + a/2)), + (Max(-(re(a) + 1)/2, (re(a) - 1)/2), Rational(1, 4)), True) + assert MT(cos(sqrt(x))*bessely(a, sqrt(x)), x, s) == \ + (-4**s*cos(pi*(a/2 - s))*gamma(s - a/2)*gamma(s + a/2)*gamma(S.Half - 2*s) + / (sqrt(pi)*gamma(S.Half - s - a/2)*gamma(S.Half - s + a/2)), + (Max(-re(a)/2, re(a)/2), Rational(1, 4)), True) + assert MT(besselj(a, sqrt(x))*bessely(a, sqrt(x)), x, s) == \ + (-cos(pi*s)*gamma(s)*gamma(a + s)*gamma(S.Half - s) + / (pi**S('3/2')*gamma(1 + a - s)), + (Max(-re(a), 0), S.Half), True) + assert MT(besselj(a, sqrt(x))*bessely(b, sqrt(x)), x, s) == \ + (-4**s*cos(pi*(a/2 - b/2 + s))*gamma(1 - 2*s) + * gamma(a/2 - b/2 + s)*gamma(a/2 + b/2 + s) + / (pi*gamma(a/2 - b/2 - s + 1)*gamma(a/2 + b/2 - s + 1)), + (Max((-re(a) + re(b))/2, (-re(a) - re(b))/2), S.Half), True) + # NOTE bessely(a, sqrt(x))**2 and bessely(a, sqrt(x))*bessely(b, sqrt(x)) + # are a mess (no matter what way you look at it ...) + assert MT(bessely(a, sqrt(x))**2, x, s)[1:] == \ + ((Max(-re(a), 0, re(a)), S.Half), True) + + # Section 8.4.22 + # TODO we can't do any of these (delicate cancellation) + + # Section 8.4.23 + assert MT(besselk(a, 2*sqrt(x)), x, s) == \ + (gamma( + s - a/2)*gamma(s + a/2)/2, (Max(-re(a)/2, re(a)/2), oo), True) + assert MT(besselj(a, 2*sqrt(2*sqrt(x)))*besselk( + a, 2*sqrt(2*sqrt(x))), x, s) == (4**(-s)*gamma(2*s)* + gamma(a/2 + s)/(2*gamma(a/2 - s + 1)), (Max(0, -re(a)/2), oo), True) + # TODO bessely(a, x)*besselk(a, x) is a mess + assert MT(besseli(a, sqrt(x))*besselk(a, sqrt(x)), x, s) == \ + (gamma(s)*gamma( + a + s)*gamma(-s + S.Half)/(2*sqrt(pi)*gamma(a - s + 1)), + (Max(-re(a), 0), S.Half), True) + assert MT(besseli(b, sqrt(x))*besselk(a, sqrt(x)), x, s) == \ + (2**(2*s - 1)*gamma(-2*s + 1)*gamma(-a/2 + b/2 + s)* \ + gamma(a/2 + b/2 + s)/(gamma(-a/2 + b/2 - s + 1)* \ + gamma(a/2 + b/2 - s + 1)), (Max(-re(a)/2 - re(b)/2, \ + re(a)/2 - re(b)/2), S.Half), True) + + # TODO products of besselk are a mess + + mt = MT(exp(-x/2)*besselk(a, x/2), x, s) + mt0 = gammasimp(trigsimp(gammasimp(mt[0].expand(func=True)))) + assert mt0 == 2*pi**Rational(3, 2)*cos(pi*s)*gamma(S.Half - s)/( + (cos(2*pi*a) - cos(2*pi*s))*gamma(-a - s + 1)*gamma(a - s + 1)) + assert mt[1:] == ((Max(-re(a), re(a)), oo), True) + # TODO exp(x/2)*besselk(a, x/2) [etc] cannot currently be done + # TODO various strange products of special orders + + +@slow +def test_expint(): + from sympy.functions.elementary.miscellaneous import Max + from sympy.functions.special.error_functions import Ci, E1, Si + from sympy.simplify.simplify import simplify + + aneg = Symbol('a', negative=True) + u = Symbol('u', polar=True) + + assert mellin_transform(E1(x), x, s) == (gamma(s)/s, (0, oo), True) + assert inverse_mellin_transform(gamma(s)/s, s, x, + (0, oo)).rewrite(expint).expand() == E1(x) + assert mellin_transform(expint(a, x), x, s) == \ + (gamma(s)/(a + s - 1), (Max(1 - re(a), 0), oo), True) + # XXX IMT has hickups with complicated strips ... + assert simplify(unpolarify( + inverse_mellin_transform(gamma(s)/(aneg + s - 1), s, x, + (1 - aneg, oo)).rewrite(expint).expand(func=True))) == \ + expint(aneg, x) + + assert mellin_transform(Si(x), x, s) == \ + (-2**s*sqrt(pi)*gamma(s/2 + S.Half)/( + 2*s*gamma(-s/2 + 1)), (-1, 0), True) + assert inverse_mellin_transform(-2**s*sqrt(pi)*gamma((s + 1)/2) + /(2*s*gamma(-s/2 + 1)), s, x, (-1, 0)) \ + == Si(x) + + assert mellin_transform(Ci(sqrt(x)), x, s) == \ + (-2**(2*s - 1)*sqrt(pi)*gamma(s)/(s*gamma(-s + S.Half)), (0, 1), True) + assert inverse_mellin_transform( + -4**s*sqrt(pi)*gamma(s)/(2*s*gamma(-s + S.Half)), + s, u, (0, 1)).expand() == Ci(sqrt(u)) + + +@slow +def test_inverse_mellin_transform(): + from sympy.core.function import expand + from sympy.functions.elementary.miscellaneous import (Max, Min) + from sympy.functions.elementary.trigonometric import cot + from sympy.simplify.powsimp import powsimp + from sympy.simplify.simplify import simplify + IMT = inverse_mellin_transform + + assert IMT(gamma(s), s, x, (0, oo)) == exp(-x) + assert IMT(gamma(-s), s, x, (-oo, 0)) == exp(-1/x) + assert simplify(IMT(s/(2*s**2 - 2), s, x, (2, oo))) == \ + (x**2 + 1)*Heaviside(1 - x)/(4*x) + + # test passing "None" + assert IMT(1/(s**2 - 1), s, x, (-1, None)) == \ + -x*Heaviside(-x + 1)/2 - Heaviside(x - 1)/(2*x) + assert IMT(1/(s**2 - 1), s, x, (None, 1)) == \ + -x*Heaviside(-x + 1)/2 - Heaviside(x - 1)/(2*x) + + # test expansion of sums + assert IMT(gamma(s) + gamma(s - 1), s, x, (1, oo)) == (x + 1)*exp(-x)/x + + # test factorisation of polys + r = symbols('r', real=True) + assert IMT(1/(s**2 + 1), s, exp(-x), (None, oo) + ).subs(x, r).rewrite(sin).simplify() \ + == sin(r)*Heaviside(1 - exp(-r)) + + # test multiplicative substitution + _a, _b = symbols('a b', positive=True) + assert IMT(_b**(-s/_a)*factorial(s/_a)/s, s, x, (0, oo)) == exp(-_b*x**_a) + assert IMT(factorial(_a/_b + s/_b)/(_a + s), s, x, (-_a, oo)) == x**_a*exp(-x**_b) + + def simp_pows(expr): + return simplify(powsimp(expand_mul(expr, deep=False), force=True)).replace(exp_polar, exp) + + # Now test the inverses of all direct transforms tested above + + # Section 8.4.2 + nu = symbols('nu', real=True) + assert IMT(-1/(nu + s), s, x, (-oo, None)) == x**nu*Heaviside(x - 1) + assert IMT(1/(nu + s), s, x, (None, oo)) == x**nu*Heaviside(1 - x) + assert simp_pows(IMT(gamma(beta)*gamma(s)/gamma(s + beta), s, x, (0, oo))) \ + == (1 - x)**(beta - 1)*Heaviside(1 - x) + assert simp_pows(IMT(gamma(beta)*gamma(1 - beta - s)/gamma(1 - s), + s, x, (-oo, None))) \ + == (x - 1)**(beta - 1)*Heaviside(x - 1) + assert simp_pows(IMT(gamma(s)*gamma(rho - s)/gamma(rho), s, x, (0, None))) \ + == (1/(x + 1))**rho + expr = IMT(d**c*d**(s - 1)*sin(pi*c) + *gamma(s)*gamma(s + c)*gamma(1 - s)*gamma(1 - s - c)/pi, + s, x, (Max(-re(c), 0), Min(1 - re(c), 1))) + assert powsimp(expand_mul(expr, deep=False)).replace(exp_polar, exp).simplify() \ + == (-d**c + x**c)/(-d + x) + + assert simplify(IMT(1/sqrt(pi)*(-c/2)*gamma(s)*gamma((1 - c)/2 - s) + *gamma(-c/2 - s)/gamma(1 - c - s), + s, x, (0, -re(c)/2))) == \ + (1 + sqrt(x + 1))**c + assert simplify(IMT(2**(a + 2*s)*b**(a + 2*s - 1)*gamma(s)*gamma(1 - a - 2*s) + /gamma(1 - a - s), s, x, (0, (-re(a) + 1)/2))) == \ + b**(a - 1)*(b**2*(sqrt(1 + x/b**2) + 1)**a + x*(sqrt(1 + x/b**2) + 1 + )**(a - 1))/(b**2 + x) + assert simplify(IMT(-2**(c + 2*s)*c*b**(c + 2*s)*gamma(s)*gamma(-c - 2*s) + / gamma(-c - s + 1), s, x, (0, -re(c)/2))) == \ + b**c*(sqrt(1 + x/b**2) + 1)**c + + # Section 8.4.5 + assert IMT(24/s**5, s, x, (0, oo)) == log(x)**4*Heaviside(1 - x) + assert expand(IMT(6/s**4, s, x, (-oo, 0)), force=True) == \ + log(x)**3*Heaviside(x - 1) + assert IMT(pi/(s*sin(pi*s)), s, x, (-1, 0)) == log(x + 1) + assert IMT(pi/(s*sin(pi*s/2)), s, x, (-2, 0)) == log(x**2 + 1) + assert IMT(pi/(s*sin(2*pi*s)), s, x, (Rational(-1, 2), 0)) == log(sqrt(x) + 1) + assert IMT(pi/(s*sin(pi*s)), s, x, (0, 1)) == log(1 + 1/x) + + # TODO + def mysimp(expr): + from sympy.core.function import expand + from sympy.simplify.powsimp import powsimp + from sympy.simplify.simplify import logcombine + return expand( + powsimp(logcombine(expr, force=True), force=True, deep=True), + force=True).replace(exp_polar, exp) + + assert mysimp(mysimp(IMT(pi/(s*tan(pi*s)), s, x, (-1, 0)))) in [ + log(1 - x)*Heaviside(1 - x) + log(x - 1)*Heaviside(x - 1), + log(x)*Heaviside(x - 1) + log(1 - 1/x)*Heaviside(x - 1) + log(-x + + 1)*Heaviside(-x + 1)] + # test passing cot + assert mysimp(IMT(pi*cot(pi*s)/s, s, x, (0, 1))) in [ + log(1/x - 1)*Heaviside(1 - x) + log(1 - 1/x)*Heaviside(x - 1), + -log(x)*Heaviside(-x + 1) + log(1 - 1/x)*Heaviside(x - 1) + log(-x + + 1)*Heaviside(-x + 1), ] + + # 8.4.14 + assert IMT(-gamma(s + S.Half)/(sqrt(pi)*s), s, x, (Rational(-1, 2), 0)) == \ + erf(sqrt(x)) + + # 8.4.19 + assert simplify(IMT(gamma(a/2 + s)/gamma(a/2 - s + 1), s, x, (-re(a)/2, Rational(3, 4)))) \ + == besselj(a, 2*sqrt(x)) + assert simplify(IMT(2**a*gamma(S.Half - 2*s)*gamma(s + (a + 1)/2) + / (gamma(1 - s - a/2)*gamma(1 - 2*s + a)), + s, x, (-(re(a) + 1)/2, Rational(1, 4)))) == \ + sin(sqrt(x))*besselj(a, sqrt(x)) + assert simplify(IMT(2**a*gamma(a/2 + s)*gamma(S.Half - 2*s) + / (gamma(S.Half - s - a/2)*gamma(1 - 2*s + a)), + s, x, (-re(a)/2, Rational(1, 4)))) == \ + cos(sqrt(x))*besselj(a, sqrt(x)) + # TODO this comes out as an amazing mess, but simplifies nicely + assert simplify(IMT(gamma(a + s)*gamma(S.Half - s) + / (sqrt(pi)*gamma(1 - s)*gamma(1 + a - s)), + s, x, (-re(a), S.Half))) == \ + besselj(a, sqrt(x))**2 + assert simplify(IMT(gamma(s)*gamma(S.Half - s) + / (sqrt(pi)*gamma(1 - s - a)*gamma(1 + a - s)), + s, x, (0, S.Half))) == \ + besselj(-a, sqrt(x))*besselj(a, sqrt(x)) + assert simplify(IMT(4**s*gamma(-2*s + 1)*gamma(a/2 + b/2 + s) + / (gamma(-a/2 + b/2 - s + 1)*gamma(a/2 - b/2 - s + 1) + *gamma(a/2 + b/2 - s + 1)), + s, x, (-(re(a) + re(b))/2, S.Half))) == \ + besselj(a, sqrt(x))*besselj(b, sqrt(x)) + + # Section 8.4.20 + # TODO this can be further simplified! + assert simplify(IMT(-2**(2*s)*cos(pi*a/2 - pi*b/2 + pi*s)*gamma(-2*s + 1) * + gamma(a/2 - b/2 + s)*gamma(a/2 + b/2 + s) / + (pi*gamma(a/2 - b/2 - s + 1)*gamma(a/2 + b/2 - s + 1)), + s, x, + (Max(-re(a)/2 - re(b)/2, -re(a)/2 + re(b)/2), S.Half))) == \ + besselj(a, sqrt(x))*-(besselj(-b, sqrt(x)) - + besselj(b, sqrt(x))*cos(pi*b))/sin(pi*b) + # TODO more + + # for coverage + + assert IMT(pi/cos(pi*s), s, x, (0, S.Half)) == sqrt(x)/(x + 1) + + +def test_fourier_transform(): + from sympy.core.function import (expand, expand_complex, expand_trig) + from sympy.polys.polytools import factor + from sympy.simplify.simplify import simplify + FT = fourier_transform + IFT = inverse_fourier_transform + + def simp(x): + return simplify(expand_trig(expand_complex(expand(x)))) + + def sinc(x): + return sin(pi*x)/(pi*x) + k = symbols('k', real=True) + f = Function("f") + + # TODO for this to work with real a, need to expand abs(a*x) to abs(a)*abs(x) + a = symbols('a', positive=True) + b = symbols('b', positive=True) + + posk = symbols('posk', positive=True) + + # Test unevaluated form + assert fourier_transform(f(x), x, k) == FourierTransform(f(x), x, k) + assert inverse_fourier_transform( + f(k), k, x) == InverseFourierTransform(f(k), k, x) + + # basic examples from wikipedia + assert simp(FT(Heaviside(1 - abs(2*a*x)), x, k)) == sinc(k/a)/a + # TODO IFT is a *mess* + assert simp(FT(Heaviside(1 - abs(a*x))*(1 - abs(a*x)), x, k)) == sinc(k/a)**2/a + # TODO IFT + + assert factor(FT(exp(-a*x)*Heaviside(x), x, k), extension=I) == \ + 1/(a + 2*pi*I*k) + # NOTE: the ift comes out in pieces + assert IFT(1/(a + 2*pi*I*x), x, posk, + noconds=False) == (exp(-a*posk), True) + assert IFT(1/(a + 2*pi*I*x), x, -posk, + noconds=False) == (0, True) + assert IFT(1/(a + 2*pi*I*x), x, symbols('k', negative=True), + noconds=False) == (0, True) + # TODO IFT without factoring comes out as meijer g + + assert factor(FT(x*exp(-a*x)*Heaviside(x), x, k), extension=I) == \ + 1/(a + 2*pi*I*k)**2 + assert FT(exp(-a*x)*sin(b*x)*Heaviside(x), x, k) == \ + b/(b**2 + (a + 2*I*pi*k)**2) + + assert FT(exp(-a*x**2), x, k) == sqrt(pi)*exp(-pi**2*k**2/a)/sqrt(a) + assert IFT(sqrt(pi/a)*exp(-(pi*k)**2/a), k, x) == exp(-a*x**2) + assert FT(exp(-a*abs(x)), x, k) == 2*a/(a**2 + 4*pi**2*k**2) + # TODO IFT (comes out as meijer G) + + # TODO besselj(n, x), n an integer > 0 actually can be done... + + # TODO are there other common transforms (no distributions!)? + + +def test_sine_transform(): + t = symbols("t") + w = symbols("w") + a = symbols("a") + f = Function("f") + + # Test unevaluated form + assert sine_transform(f(t), t, w) == SineTransform(f(t), t, w) + assert inverse_sine_transform( + f(w), w, t) == InverseSineTransform(f(w), w, t) + + assert sine_transform(1/sqrt(t), t, w) == 1/sqrt(w) + assert inverse_sine_transform(1/sqrt(w), w, t) == 1/sqrt(t) + + assert sine_transform((1/sqrt(t))**3, t, w) == 2*sqrt(w) + + assert sine_transform(t**(-a), t, w) == 2**( + -a + S.Half)*w**(a - 1)*gamma(-a/2 + 1)/gamma((a + 1)/2) + assert inverse_sine_transform(2**(-a + S( + 1)/2)*w**(a - 1)*gamma(-a/2 + 1)/gamma(a/2 + S.Half), w, t) == t**(-a) + + assert sine_transform( + exp(-a*t), t, w) == sqrt(2)*w/(sqrt(pi)*(a**2 + w**2)) + assert inverse_sine_transform( + sqrt(2)*w/(sqrt(pi)*(a**2 + w**2)), w, t) == exp(-a*t) + + assert sine_transform( + log(t)/t, t, w) == sqrt(2)*sqrt(pi)*-(log(w**2) + 2*EulerGamma)/4 + + assert sine_transform( + t*exp(-a*t**2), t, w) == sqrt(2)*w*exp(-w**2/(4*a))/(4*a**Rational(3, 2)) + assert inverse_sine_transform( + sqrt(2)*w*exp(-w**2/(4*a))/(4*a**Rational(3, 2)), w, t) == t*exp(-a*t**2) + + +def test_cosine_transform(): + from sympy.functions.special.error_functions import (Ci, Si) + + t = symbols("t") + w = symbols("w") + a = symbols("a") + f = Function("f") + + # Test unevaluated form + assert cosine_transform(f(t), t, w) == CosineTransform(f(t), t, w) + assert inverse_cosine_transform( + f(w), w, t) == InverseCosineTransform(f(w), w, t) + + assert cosine_transform(1/sqrt(t), t, w) == 1/sqrt(w) + assert inverse_cosine_transform(1/sqrt(w), w, t) == 1/sqrt(t) + + assert cosine_transform(1/( + a**2 + t**2), t, w) == sqrt(2)*sqrt(pi)*exp(-a*w)/(2*a) + + assert cosine_transform(t**( + -a), t, w) == 2**(-a + S.Half)*w**(a - 1)*gamma((-a + 1)/2)/gamma(a/2) + assert inverse_cosine_transform(2**(-a + S( + 1)/2)*w**(a - 1)*gamma(-a/2 + S.Half)/gamma(a/2), w, t) == t**(-a) + + assert cosine_transform( + exp(-a*t), t, w) == sqrt(2)*a/(sqrt(pi)*(a**2 + w**2)) + assert inverse_cosine_transform( + sqrt(2)*a/(sqrt(pi)*(a**2 + w**2)), w, t) == exp(-a*t) + + assert cosine_transform(exp(-a*sqrt(t))*cos(a*sqrt( + t)), t, w) == a*exp(-a**2/(2*w))/(2*w**Rational(3, 2)) + + assert cosine_transform(1/(a + t), t, w) == sqrt(2)*( + (-2*Si(a*w) + pi)*sin(a*w)/2 - cos(a*w)*Ci(a*w))/sqrt(pi) + assert inverse_cosine_transform(sqrt(2)*meijerg(((S.Half, 0), ()), ( + (S.Half, 0, 0), (S.Half,)), a**2*w**2/4)/(2*pi), w, t) == 1/(a + t) + + assert cosine_transform(1/sqrt(a**2 + t**2), t, w) == sqrt(2)*meijerg( + ((S.Half,), ()), ((0, 0), (S.Half,)), a**2*w**2/4)/(2*sqrt(pi)) + assert inverse_cosine_transform(sqrt(2)*meijerg(((S.Half,), ()), ((0, 0), (S.Half,)), a**2*w**2/4)/(2*sqrt(pi)), w, t) == 1/(t*sqrt(a**2/t**2 + 1)) + + +def test_hankel_transform(): + r = Symbol("r") + k = Symbol("k") + nu = Symbol("nu") + m = Symbol("m") + a = symbols("a") + + assert hankel_transform(1/r, r, k, 0) == 1/k + assert inverse_hankel_transform(1/k, k, r, 0) == 1/r + + assert hankel_transform( + 1/r**m, r, k, 0) == 2**(-m + 1)*k**(m - 2)*gamma(-m/2 + 1)/gamma(m/2) + assert inverse_hankel_transform( + 2**(-m + 1)*k**(m - 2)*gamma(-m/2 + 1)/gamma(m/2), k, r, 0) == r**(-m) + + assert hankel_transform(1/r**m, r, k, nu) == ( + 2*2**(-m)*k**(m - 2)*gamma(-m/2 + nu/2 + 1)/gamma(m/2 + nu/2)) + assert inverse_hankel_transform(2**(-m + 1)*k**( + m - 2)*gamma(-m/2 + nu/2 + 1)/gamma(m/2 + nu/2), k, r, nu) == r**(-m) + + assert hankel_transform(r**nu*exp(-a*r), r, k, nu) == \ + 2**(nu + 1)*a*k**(-nu - 3)*(a**2/k**2 + 1)**(-nu - S( + 3)/2)*gamma(nu + Rational(3, 2))/sqrt(pi) + assert inverse_hankel_transform( + 2**(nu + 1)*a*k**(-nu - 3)*(a**2/k**2 + 1)**(-nu - Rational(3, 2))*gamma( + nu + Rational(3, 2))/sqrt(pi), k, r, nu) == r**nu*exp(-a*r) + + +def test_issue_7181(): + assert mellin_transform(1/(1 - x), x, s) != None + + +def test_issue_8882(): + # This is the original test. + # from sympy import diff, Integral, integrate + # r = Symbol('r') + # psi = 1/r*sin(r)*exp(-(a0*r)) + # h = -1/2*diff(psi, r, r) - 1/r*psi + # f = 4*pi*psi*h*r**2 + # assert integrate(f, (r, -oo, 3), meijerg=True).has(Integral) == True + + # To save time, only the critical part is included. + F = -a**(-s + 1)*(4 + 1/a**2)**(-s/2)*sqrt(1/a**2)*exp(-s*I*pi)* \ + sin(s*atan(sqrt(1/a**2)/2))*gamma(s) + raises(IntegralTransformError, lambda: + inverse_mellin_transform(F, s, x, (-1, oo), + **{'as_meijerg': True, 'needeval': True})) + + +def test_issue_12591(): + x, y = symbols("x y", real=True) + assert fourier_transform(exp(x), x, y) == FourierTransform(exp(x), x, y) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_trigonometry.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_trigonometry.py new file mode 100644 index 0000000000000000000000000000000000000000..857c8503c5aa690d66e9cdab49730b4ea655a52c --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/tests/test_trigonometry.py @@ -0,0 +1,98 @@ +from sympy.core import Ne, Rational, Symbol +from sympy.functions import sin, cos, tan, csc, sec, cot, log, Piecewise +from sympy.integrals.trigonometry import trigintegrate + +x = Symbol('x') + + +def test_trigintegrate_odd(): + assert trigintegrate(Rational(1), x) == x + assert trigintegrate(x, x) is None + assert trigintegrate(x**2, x) is None + + assert trigintegrate(sin(x), x) == -cos(x) + assert trigintegrate(cos(x), x) == sin(x) + + assert trigintegrate(sin(3*x), x) == -cos(3*x)/3 + assert trigintegrate(cos(3*x), x) == sin(3*x)/3 + + y = Symbol('y') + assert trigintegrate(sin(y*x), x) == Piecewise( + (-cos(y*x)/y, Ne(y, 0)), (0, True)) + assert trigintegrate(cos(y*x), x) == Piecewise( + (sin(y*x)/y, Ne(y, 0)), (x, True)) + assert trigintegrate(sin(y*x)**2, x) == Piecewise( + ((x*y/2 - sin(x*y)*cos(x*y)/2)/y, Ne(y, 0)), (0, True)) + assert trigintegrate(sin(y*x)*cos(y*x), x) == Piecewise( + (sin(x*y)**2/(2*y), Ne(y, 0)), (0, True)) + assert trigintegrate(cos(y*x)**2, x) == Piecewise( + ((x*y/2 + sin(x*y)*cos(x*y)/2)/y, Ne(y, 0)), (x, True)) + + y = Symbol('y', positive=True) + # TODO: remove conds='none' below. For this to work we would have to rule + # out (e.g. by trying solve) the condition y = 0, incompatible with + # y.is_positive being True. + assert trigintegrate(sin(y*x), x, conds='none') == -cos(y*x)/y + assert trigintegrate(cos(y*x), x, conds='none') == sin(y*x)/y + + assert trigintegrate(sin(x)*cos(x), x) == sin(x)**2/2 + assert trigintegrate(sin(x)*cos(x)**2, x) == -cos(x)**3/3 + assert trigintegrate(sin(x)**2*cos(x), x) == sin(x)**3/3 + + # check if it selects right function to substitute, + # so the result is kept simple + assert trigintegrate(sin(x)**7 * cos(x), x) == sin(x)**8/8 + assert trigintegrate(sin(x) * cos(x)**7, x) == -cos(x)**8/8 + + assert trigintegrate(sin(x)**7 * cos(x)**3, x) == \ + -sin(x)**10/10 + sin(x)**8/8 + assert trigintegrate(sin(x)**3 * cos(x)**7, x) == \ + cos(x)**10/10 - cos(x)**8/8 + + # both n, m are odd and -ve, and not necessarily equal + assert trigintegrate(sin(x)**-1*cos(x)**-1, x) == \ + -log(sin(x)**2 - 1)/2 + log(sin(x)) + + +def test_trigintegrate_even(): + assert trigintegrate(sin(x)**2, x) == x/2 - cos(x)*sin(x)/2 + assert trigintegrate(cos(x)**2, x) == x/2 + cos(x)*sin(x)/2 + + assert trigintegrate(sin(3*x)**2, x) == x/2 - cos(3*x)*sin(3*x)/6 + assert trigintegrate(cos(3*x)**2, x) == x/2 + cos(3*x)*sin(3*x)/6 + assert trigintegrate(sin(x)**2 * cos(x)**2, x) == \ + x/8 - sin(2*x)*cos(2*x)/16 + + assert trigintegrate(sin(x)**4 * cos(x)**2, x) == \ + x/16 - sin(x) *cos(x)/16 - sin(x)**3*cos(x)/24 + \ + sin(x)**5*cos(x)/6 + + assert trigintegrate(sin(x)**2 * cos(x)**4, x) == \ + x/16 + cos(x) *sin(x)/16 + cos(x)**3*sin(x)/24 - \ + cos(x)**5*sin(x)/6 + + assert trigintegrate(sin(x)**(-4), x) == -2*cos(x)/(3*sin(x)) \ + - cos(x)/(3*sin(x)**3) + + assert trigintegrate(cos(x)**(-6), x) == sin(x)/(5*cos(x)**5) \ + + 4*sin(x)/(15*cos(x)**3) + 8*sin(x)/(15*cos(x)) + + +def test_trigintegrate_mixed(): + assert trigintegrate(sin(x)*sec(x), x) == -log(cos(x)) + assert trigintegrate(sin(x)*csc(x), x) == x + assert trigintegrate(sin(x)*cot(x), x) == sin(x) + + assert trigintegrate(cos(x)*sec(x), x) == x + assert trigintegrate(cos(x)*csc(x), x) == log(sin(x)) + assert trigintegrate(cos(x)*tan(x), x) == -cos(x) + assert trigintegrate(cos(x)*cot(x), x) == log(cos(x) - 1)/2 \ + - log(cos(x) + 1)/2 + cos(x) + assert trigintegrate(cot(x)*cos(x)**2, x) == log(sin(x)) - sin(x)**2/2 + + +def test_trigintegrate_symbolic(): + n = Symbol('n', integer=True) + assert trigintegrate(cos(x)**n, x) is None + assert trigintegrate(sin(x)**n, x) is None + assert trigintegrate(cot(x)**n, x) is None diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/transforms.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/transforms.py new file mode 100644 index 0000000000000000000000000000000000000000..19dbd990e4f0320e76707a1a2a8b1601fcd8a3df --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/transforms.py @@ -0,0 +1,1590 @@ +""" Integral Transforms """ +from functools import reduce, wraps +from itertools import repeat +from sympy.core import S, pi +from sympy.core.add import Add +from sympy.core.function import ( + AppliedUndef, count_ops, expand, expand_mul, Function) +from sympy.core.mul import Mul +from sympy.core.intfunc import igcd, ilcm +from sympy.core.sorting import default_sort_key +from sympy.core.symbol import Dummy +from sympy.core.traversal import postorder_traversal +from sympy.functions.combinatorial.factorials import factorial, rf +from sympy.functions.elementary.complexes import re, arg, Abs +from sympy.functions.elementary.exponential import exp, exp_polar +from sympy.functions.elementary.hyperbolic import cosh, coth, sinh, tanh +from sympy.functions.elementary.integers import ceiling +from sympy.functions.elementary.miscellaneous import Max, Min, sqrt +from sympy.functions.elementary.piecewise import piecewise_fold +from sympy.functions.elementary.trigonometric import cos, cot, sin, tan +from sympy.functions.special.bessel import besselj +from sympy.functions.special.delta_functions import Heaviside +from sympy.functions.special.gamma_functions import gamma +from sympy.functions.special.hyper import meijerg +from sympy.integrals import integrate, Integral +from sympy.integrals.meijerint import _dummy +from sympy.logic.boolalg import to_cnf, conjuncts, disjuncts, Or, And +from sympy.polys.polyroots import roots +from sympy.polys.polytools import factor, Poly +from sympy.polys.rootoftools import CRootOf +from sympy.utilities.iterables import iterable +from sympy.utilities.misc import debug + + +########################################################################## +# Helpers / Utilities +########################################################################## + + +class IntegralTransformError(NotImplementedError): + """ + Exception raised in relation to problems computing transforms. + + Explanation + =========== + + This class is mostly used internally; if integrals cannot be computed + objects representing unevaluated transforms are usually returned. + + The hint ``needeval=True`` can be used to disable returning transform + objects, and instead raise this exception if an integral cannot be + computed. + """ + def __init__(self, transform, function, msg): + super().__init__( + "%s Transform could not be computed: %s." % (transform, msg)) + self.function = function + + +class IntegralTransform(Function): + """ + Base class for integral transforms. + + Explanation + =========== + + This class represents unevaluated transforms. + + To implement a concrete transform, derive from this class and implement + the ``_compute_transform(f, x, s, **hints)`` and ``_as_integral(f, x, s)`` + functions. If the transform cannot be computed, raise :obj:`IntegralTransformError`. + + Also set ``cls._name``. For instance, + + >>> from sympy import LaplaceTransform + >>> LaplaceTransform._name + 'Laplace' + + Implement ``self._collapse_extra`` if your function returns more than just a + number and possibly a convergence condition. + """ + + @property + def function(self): + """ The function to be transformed. """ + return self.args[0] + + @property + def function_variable(self): + """ The dependent variable of the function to be transformed. """ + return self.args[1] + + @property + def transform_variable(self): + """ The independent transform variable. """ + return self.args[2] + + @property + def free_symbols(self): + """ + This method returns the symbols that will exist when the transform + is evaluated. + """ + return self.function.free_symbols.union({self.transform_variable}) \ + - {self.function_variable} + + def _compute_transform(self, f, x, s, **hints): + raise NotImplementedError + + def _as_integral(self, f, x, s): + raise NotImplementedError + + def _collapse_extra(self, extra): + cond = And(*extra) + if cond == False: + raise IntegralTransformError(self.__class__.name, None, '') + return cond + + def _try_directly(self, **hints): + T = None + try_directly = not any(func.has(self.function_variable) + for func in self.function.atoms(AppliedUndef)) + if try_directly: + try: + T = self._compute_transform(self.function, + self.function_variable, self.transform_variable, **hints) + except IntegralTransformError: + debug('[IT _try ] Caught IntegralTransformError, returns None') + T = None + + fn = self.function + if not fn.is_Add: + fn = expand_mul(fn) + return fn, T + + def doit(self, **hints): + """ + Try to evaluate the transform in closed form. + + Explanation + =========== + + This general function handles linearity, but apart from that leaves + pretty much everything to _compute_transform. + + Standard hints are the following: + + - ``simplify``: whether or not to simplify the result + - ``noconds``: if True, do not return convergence conditions + - ``needeval``: if True, raise IntegralTransformError instead of + returning IntegralTransform objects + + The default values of these hints depend on the concrete transform, + usually the default is + ``(simplify, noconds, needeval) = (True, False, False)``. + """ + needeval = hints.pop('needeval', False) + simplify = hints.pop('simplify', True) + hints['simplify'] = simplify + + fn, T = self._try_directly(**hints) + + if T is not None: + return T + + if fn.is_Add: + hints['needeval'] = needeval + res = [self.__class__(*([x] + list(self.args[1:]))).doit(**hints) + for x in fn.args] + extra = [] + ress = [] + for x in res: + if not isinstance(x, tuple): + x = [x] + ress.append(x[0]) + if len(x) == 2: + # only a condition + extra.append(x[1]) + elif len(x) > 2: + # some region parameters and a condition (Mellin, Laplace) + extra += [x[1:]] + if simplify==True: + res = Add(*ress).simplify() + else: + res = Add(*ress) + if not extra: + return res + try: + extra = self._collapse_extra(extra) + if iterable(extra): + return (res,) + tuple(extra) + else: + return (res, extra) + except IntegralTransformError: + pass + + if needeval: + raise IntegralTransformError( + self.__class__._name, self.function, 'needeval') + + # TODO handle derivatives etc + + # pull out constant coefficients + coeff, rest = fn.as_coeff_mul(self.function_variable) + return coeff*self.__class__(*([Mul(*rest)] + list(self.args[1:]))) + + @property + def as_integral(self): + return self._as_integral(self.function, self.function_variable, + self.transform_variable) + + def _eval_rewrite_as_Integral(self, *args, **kwargs): + return self.as_integral + + +def _simplify(expr, doit): + if doit: + from sympy.simplify import simplify + from sympy.simplify.powsimp import powdenest + return simplify(powdenest(piecewise_fold(expr), polar=True)) + return expr + + +def _noconds_(default): + """ + This is a decorator generator for dropping convergence conditions. + + Explanation + =========== + + Suppose you define a function ``transform(*args)`` which returns a tuple of + the form ``(result, cond1, cond2, ...)``. + + Decorating it ``@_noconds_(default)`` will add a new keyword argument + ``noconds`` to it. If ``noconds=True``, the return value will be altered to + be only ``result``, whereas if ``noconds=False`` the return value will not + be altered. + + The default value of the ``noconds`` keyword will be ``default`` (i.e. the + argument of this function). + """ + def make_wrapper(func): + @wraps(func) + def wrapper(*args, noconds=default, **kwargs): + res = func(*args, **kwargs) + if noconds: + return res[0] + return res + return wrapper + return make_wrapper +_noconds = _noconds_(False) + + +########################################################################## +# Mellin Transform +########################################################################## + +def _default_integrator(f, x): + return integrate(f, (x, S.Zero, S.Infinity)) + + +@_noconds +def _mellin_transform(f, x, s_, integrator=_default_integrator, simplify=True): + """ Backend function to compute Mellin transforms. """ + # We use a fresh dummy, because assumptions on s might drop conditions on + # convergence of the integral. + s = _dummy('s', 'mellin-transform', f) + F = integrator(x**(s - 1) * f, x) + + if not F.has(Integral): + return _simplify(F.subs(s, s_), simplify), (S.NegativeInfinity, S.Infinity), S.true + + if not F.is_Piecewise: # XXX can this work if integration gives continuous result now? + raise IntegralTransformError('Mellin', f, 'could not compute integral') + + F, cond = F.args[0] + if F.has(Integral): + raise IntegralTransformError( + 'Mellin', f, 'integral in unexpected form') + + def process_conds(cond): + """ + Turn ``cond`` into a strip (a, b), and auxiliary conditions. + """ + from sympy.solvers.inequalities import _solve_inequality + a = S.NegativeInfinity + b = S.Infinity + aux = S.true + conds = conjuncts(to_cnf(cond)) + t = Dummy('t', real=True) + for c in conds: + a_ = S.Infinity + b_ = S.NegativeInfinity + aux_ = [] + for d in disjuncts(c): + d_ = d.replace( + re, lambda x: x.as_real_imag()[0]).subs(re(s), t) + if not d.is_Relational or \ + d.rel_op in ('==', '!=') \ + or d_.has(s) or not d_.has(t): + aux_ += [d] + continue + soln = _solve_inequality(d_, t) + if not soln.is_Relational or \ + soln.rel_op in ('==', '!='): + aux_ += [d] + continue + if soln.lts == t: + b_ = Max(soln.gts, b_) + else: + a_ = Min(soln.lts, a_) + if a_ is not S.Infinity and a_ != b: + a = Max(a_, a) + elif b_ is not S.NegativeInfinity and b_ != a: + b = Min(b_, b) + else: + aux = And(aux, Or(*aux_)) + return a, b, aux + + conds = [process_conds(c) for c in disjuncts(cond)] + conds = [x for x in conds if x[2] != False] + conds.sort(key=lambda x: (x[0] - x[1], count_ops(x[2]))) + + if not conds: + raise IntegralTransformError('Mellin', f, 'no convergence found') + + a, b, aux = conds[0] + return _simplify(F.subs(s, s_), simplify), (a, b), aux + + +class MellinTransform(IntegralTransform): + """ + Class representing unevaluated Mellin transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute Mellin transforms, see the :func:`mellin_transform` + docstring. + """ + + _name = 'Mellin' + + def _compute_transform(self, f, x, s, **hints): + return _mellin_transform(f, x, s, **hints) + + def _as_integral(self, f, x, s): + return Integral(f*x**(s - 1), (x, S.Zero, S.Infinity)) + + def _collapse_extra(self, extra): + a = [] + b = [] + cond = [] + for (sa, sb), c in extra: + a += [sa] + b += [sb] + cond += [c] + res = (Max(*a), Min(*b)), And(*cond) + if (res[0][0] >= res[0][1]) == True or res[1] == False: + raise IntegralTransformError( + 'Mellin', None, 'no combined convergence.') + return res + + +def mellin_transform(f, x, s, **hints): + r""" + Compute the Mellin transform `F(s)` of `f(x)`, + + .. math :: F(s) = \int_0^\infty x^{s-1} f(x) \mathrm{d}x. + + For all "sensible" functions, this converges absolutely in a strip + `a < \operatorname{Re}(s) < b`. + + Explanation + =========== + + The Mellin transform is related via change of variables to the Fourier + transform, and also to the (bilateral) Laplace transform. + + This function returns ``(F, (a, b), cond)`` + where ``F`` is the Mellin transform of ``f``, ``(a, b)`` is the fundamental strip + (as above), and ``cond`` are auxiliary convergence conditions. + + If the integral cannot be computed in closed form, this function returns + an unevaluated :class:`MellinTransform` object. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. If ``noconds=False``, + then only `F` will be returned (i.e. not ``cond``, and also not the strip + ``(a, b)``). + + Examples + ======== + + >>> from sympy import mellin_transform, exp + >>> from sympy.abc import x, s + >>> mellin_transform(exp(-x), x, s) + (gamma(s), (0, oo), True) + + See Also + ======== + + inverse_mellin_transform, laplace_transform, fourier_transform + hankel_transform, inverse_hankel_transform + """ + return MellinTransform(f, x, s).doit(**hints) + + +def _rewrite_sin(m_n, s, a, b): + """ + Re-write the sine function ``sin(m*s + n)`` as gamma functions, compatible + with the strip (a, b). + + Return ``(gamma1, gamma2, fac)`` so that ``f == fac/(gamma1 * gamma2)``. + + Examples + ======== + + >>> from sympy.integrals.transforms import _rewrite_sin + >>> from sympy import pi, S + >>> from sympy.abc import s + >>> _rewrite_sin((pi, 0), s, 0, 1) + (gamma(s), gamma(1 - s), pi) + >>> _rewrite_sin((pi, 0), s, 1, 0) + (gamma(s - 1), gamma(2 - s), -pi) + >>> _rewrite_sin((pi, 0), s, -1, 0) + (gamma(s + 1), gamma(-s), -pi) + >>> _rewrite_sin((pi, pi/2), s, S(1)/2, S(3)/2) + (gamma(s - 1/2), gamma(3/2 - s), -pi) + >>> _rewrite_sin((pi, pi), s, 0, 1) + (gamma(s), gamma(1 - s), -pi) + >>> _rewrite_sin((2*pi, 0), s, 0, S(1)/2) + (gamma(2*s), gamma(1 - 2*s), pi) + >>> _rewrite_sin((2*pi, 0), s, S(1)/2, 1) + (gamma(2*s - 1), gamma(2 - 2*s), -pi) + """ + # (This is a separate function because it is moderately complicated, + # and I want to doctest it.) + # We want to use pi/sin(pi*x) = gamma(x)*gamma(1-x). + # But there is one complication: the gamma functions determine the + # integration contour in the definition of the G-function. Usually + # it would not matter if this is slightly shifted, unless this way + # we create an undefined function! + # So we try to write this in such a way that the gammas are + # eminently on the right side of the strip. + m, n = m_n + + m = expand_mul(m/pi) + n = expand_mul(n/pi) + r = ceiling(-m*a - n.as_real_imag()[0]) # Don't use re(n), does not expand + return gamma(m*s + n + r), gamma(1 - n - r - m*s), (-1)**r*pi + + +class MellinTransformStripError(ValueError): + """ + Exception raised by _rewrite_gamma. Mainly for internal use. + """ + pass + + +def _rewrite_gamma(f, s, a, b): + """ + Try to rewrite the product f(s) as a product of gamma functions, + so that the inverse Mellin transform of f can be expressed as a meijer + G function. + + Explanation + =========== + + Return (an, ap), (bm, bq), arg, exp, fac such that + G((an, ap), (bm, bq), arg/z**exp)*fac is the inverse Mellin transform of f(s). + + Raises IntegralTransformError or MellinTransformStripError on failure. + + It is asserted that f has no poles in the fundamental strip designated by + (a, b). One of a and b is allowed to be None. The fundamental strip is + important, because it determines the inversion contour. + + This function can handle exponentials, linear factors, trigonometric + functions. + + This is a helper function for inverse_mellin_transform that will not + attempt any transformations on f. + + Examples + ======== + + >>> from sympy.integrals.transforms import _rewrite_gamma + >>> from sympy.abc import s + >>> from sympy import oo + >>> _rewrite_gamma(s*(s+3)*(s-1), s, -oo, oo) + (([], [-3, 0, 1]), ([-2, 1, 2], []), 1, 1, -1) + >>> _rewrite_gamma((s-1)**2, s, -oo, oo) + (([], [1, 1]), ([2, 2], []), 1, 1, 1) + + Importance of the fundamental strip: + + >>> _rewrite_gamma(1/s, s, 0, oo) + (([1], []), ([], [0]), 1, 1, 1) + >>> _rewrite_gamma(1/s, s, None, oo) + (([1], []), ([], [0]), 1, 1, 1) + >>> _rewrite_gamma(1/s, s, 0, None) + (([1], []), ([], [0]), 1, 1, 1) + >>> _rewrite_gamma(1/s, s, -oo, 0) + (([], [1]), ([0], []), 1, 1, -1) + >>> _rewrite_gamma(1/s, s, None, 0) + (([], [1]), ([0], []), 1, 1, -1) + >>> _rewrite_gamma(1/s, s, -oo, None) + (([], [1]), ([0], []), 1, 1, -1) + + >>> _rewrite_gamma(2**(-s+3), s, -oo, oo) + (([], []), ([], []), 1/2, 1, 8) + """ + # Our strategy will be as follows: + # 1) Guess a constant c such that the inversion integral should be + # performed wrt s'=c*s (instead of plain s). Write s for s'. + # 2) Process all factors, rewrite them independently as gamma functions in + # argument s, or exponentials of s. + # 3) Try to transform all gamma functions s.t. they have argument + # a+s or a-s. + # 4) Check that the resulting G function parameters are valid. + # 5) Combine all the exponentials. + + a_, b_ = S([a, b]) + + def left(c, is_numer): + """ + Decide whether pole at c lies to the left of the fundamental strip. + """ + # heuristically, this is the best chance for us to solve the inequalities + c = expand(re(c)) + if a_ is None and b_ is S.Infinity: + return True + if a_ is None: + return c < b_ + if b_ is None: + return c <= a_ + if (c >= b_) == True: + return False + if (c <= a_) == True: + return True + if is_numer: + return None + if a_.free_symbols or b_.free_symbols or c.free_symbols: + return None # XXX + #raise IntegralTransformError('Inverse Mellin', f, + # 'Could not determine position of singularity %s' + # ' relative to fundamental strip' % c) + raise MellinTransformStripError('Pole inside critical strip?') + + # 1) + s_multipliers = [] + for g in f.atoms(gamma): + if not g.has(s): + continue + arg = g.args[0] + if arg.is_Add: + arg = arg.as_independent(s)[1] + coeff, _ = arg.as_coeff_mul(s) + s_multipliers += [coeff] + for g in f.atoms(sin, cos, tan, cot): + if not g.has(s): + continue + arg = g.args[0] + if arg.is_Add: + arg = arg.as_independent(s)[1] + coeff, _ = arg.as_coeff_mul(s) + s_multipliers += [coeff/pi] + s_multipliers = [Abs(x) if x.is_extended_real else x for x in s_multipliers] + common_coefficient = S.One + for x in s_multipliers: + if not x.is_Rational: + common_coefficient = x + break + s_multipliers = [x/common_coefficient for x in s_multipliers] + if not (all(x.is_Rational for x in s_multipliers) and + common_coefficient.is_extended_real): + raise IntegralTransformError("Gamma", None, "Nonrational multiplier") + s_multiplier = common_coefficient/reduce(ilcm, [S(x.q) + for x in s_multipliers], S.One) + if s_multiplier == common_coefficient: + if len(s_multipliers) == 0: + s_multiplier = common_coefficient + else: + s_multiplier = common_coefficient \ + *reduce(igcd, [S(x.p) for x in s_multipliers]) + + f = f.subs(s, s/s_multiplier) + fac = S.One/s_multiplier + exponent = S.One/s_multiplier + if a_ is not None: + a_ *= s_multiplier + if b_ is not None: + b_ *= s_multiplier + + # 2) + numer, denom = f.as_numer_denom() + numer = Mul.make_args(numer) + denom = Mul.make_args(denom) + args = list(zip(numer, repeat(True))) + list(zip(denom, repeat(False))) + + facs = [] + dfacs = [] + # *_gammas will contain pairs (a, c) representing Gamma(a*s + c) + numer_gammas = [] + denom_gammas = [] + # exponentials will contain bases for exponentials of s + exponentials = [] + + def exception(fact): + return IntegralTransformError("Inverse Mellin", f, "Unrecognised form '%s'." % fact) + while args: + fact, is_numer = args.pop() + if is_numer: + ugammas, lgammas = numer_gammas, denom_gammas + ufacs = facs + else: + ugammas, lgammas = denom_gammas, numer_gammas + ufacs = dfacs + + def linear_arg(arg): + """ Test if arg is of form a*s+b, raise exception if not. """ + if not arg.is_polynomial(s): + raise exception(fact) + p = Poly(arg, s) + if p.degree() != 1: + raise exception(fact) + return p.all_coeffs() + + # constants + if not fact.has(s): + ufacs += [fact] + # exponentials + elif fact.is_Pow or isinstance(fact, exp): + if fact.is_Pow: + base = fact.base + exp_ = fact.exp + else: + base = exp_polar(1) + exp_ = fact.exp + if exp_.is_Integer: + cond = is_numer + if exp_ < 0: + cond = not cond + args += [(base, cond)]*Abs(exp_) + continue + elif not base.has(s): + a, b = linear_arg(exp_) + if not is_numer: + base = 1/base + exponentials += [base**a] + facs += [base**b] + else: + raise exception(fact) + # linear factors + elif fact.is_polynomial(s): + p = Poly(fact, s) + if p.degree() != 1: + # We completely factor the poly. For this we need the roots. + # Now roots() only works in some cases (low degree), and CRootOf + # only works without parameters. So try both... + coeff = p.LT()[1] + rs = roots(p, s) + if len(rs) != p.degree(): + rs = CRootOf.all_roots(p) + ufacs += [coeff] + args += [(s - c, is_numer) for c in rs] + continue + a, c = p.all_coeffs() + ufacs += [a] + c /= -a + # Now need to convert s - c + if left(c, is_numer): + ugammas += [(S.One, -c + 1)] + lgammas += [(S.One, -c)] + else: + ufacs += [-1] + ugammas += [(S.NegativeOne, c + 1)] + lgammas += [(S.NegativeOne, c)] + elif isinstance(fact, gamma): + a, b = linear_arg(fact.args[0]) + if is_numer: + if (a > 0 and (left(-b/a, is_numer) == False)) or \ + (a < 0 and (left(-b/a, is_numer) == True)): + raise NotImplementedError( + 'Gammas partially over the strip.') + ugammas += [(a, b)] + elif isinstance(fact, sin): + # We try to re-write all trigs as gammas. This is not in + # general the best strategy, since sometimes this is impossible, + # but rewriting as exponentials would work. However trig functions + # in inverse mellin transforms usually all come from simplifying + # gamma terms, so this should work. + a = fact.args[0] + if is_numer: + # No problem with the poles. + gamma1, gamma2, fac_ = gamma(a/pi), gamma(1 - a/pi), pi + else: + gamma1, gamma2, fac_ = _rewrite_sin(linear_arg(a), s, a_, b_) + args += [(gamma1, not is_numer), (gamma2, not is_numer)] + ufacs += [fac_] + elif isinstance(fact, tan): + a = fact.args[0] + args += [(sin(a, evaluate=False), is_numer), + (sin(pi/2 - a, evaluate=False), not is_numer)] + elif isinstance(fact, cos): + a = fact.args[0] + args += [(sin(pi/2 - a, evaluate=False), is_numer)] + elif isinstance(fact, cot): + a = fact.args[0] + args += [(sin(pi/2 - a, evaluate=False), is_numer), + (sin(a, evaluate=False), not is_numer)] + else: + raise exception(fact) + + fac *= Mul(*facs)/Mul(*dfacs) + + # 3) + an, ap, bm, bq = [], [], [], [] + for gammas, plus, minus, is_numer in [(numer_gammas, an, bm, True), + (denom_gammas, bq, ap, False)]: + while gammas: + a, c = gammas.pop() + if a != -1 and a != +1: + # We use the gamma function multiplication theorem. + p = Abs(S(a)) + newa = a/p + newc = c/p + if not a.is_Integer: + raise TypeError("a is not an integer") + for k in range(p): + gammas += [(newa, newc + k/p)] + if is_numer: + fac *= (2*pi)**((1 - p)/2) * p**(c - S.Half) + exponentials += [p**a] + else: + fac /= (2*pi)**((1 - p)/2) * p**(c - S.Half) + exponentials += [p**(-a)] + continue + if a == +1: + plus.append(1 - c) + else: + minus.append(c) + + # 4) + # TODO + + # 5) + arg = Mul(*exponentials) + + # for testability, sort the arguments + an.sort(key=default_sort_key) + ap.sort(key=default_sort_key) + bm.sort(key=default_sort_key) + bq.sort(key=default_sort_key) + + return (an, ap), (bm, bq), arg, exponent, fac + + +@_noconds_(True) +def _inverse_mellin_transform(F, s, x_, strip, as_meijerg=False): + """ A helper for the real inverse_mellin_transform function, this one here + assumes x to be real and positive. """ + x = _dummy('t', 'inverse-mellin-transform', F, positive=True) + # Actually, we won't try integration at all. Instead we use the definition + # of the Meijer G function as a fairly general inverse mellin transform. + F = F.rewrite(gamma) + for g in [factor(F), expand_mul(F), expand(F)]: + if g.is_Add: + # do all terms separately + ress = [_inverse_mellin_transform(G, s, x, strip, as_meijerg, + noconds=False) + for G in g.args] + conds = [p[1] for p in ress] + ress = [p[0] for p in ress] + res = Add(*ress) + if not as_meijerg: + res = factor(res, gens=res.atoms(Heaviside)) + return res.subs(x, x_), And(*conds) + + try: + a, b, C, e, fac = _rewrite_gamma(g, s, strip[0], strip[1]) + except IntegralTransformError: + continue + try: + G = meijerg(a, b, C/x**e) + except ValueError: + continue + if as_meijerg: + h = G + else: + try: + from sympy.simplify import hyperexpand + h = hyperexpand(G) + except NotImplementedError: + raise IntegralTransformError( + 'Inverse Mellin', F, 'Could not calculate integral') + + if h.is_Piecewise and len(h.args) == 3: + # XXX we break modularity here! + h = Heaviside(x - Abs(C))*h.args[0].args[0] \ + + Heaviside(Abs(C) - x)*h.args[1].args[0] + # We must ensure that the integral along the line we want converges, + # and return that value. + # See [L], 5.2 + cond = [Abs(arg(G.argument)) < G.delta*pi] + # Note: we allow ">=" here, this corresponds to convergence if we let + # limits go to oo symmetrically. ">" corresponds to absolute convergence. + cond += [And(Or(len(G.ap) != len(G.bq), 0 >= re(G.nu) + 1), + Abs(arg(G.argument)) == G.delta*pi)] + cond = Or(*cond) + if cond == False: + raise IntegralTransformError( + 'Inverse Mellin', F, 'does not converge') + return (h*fac).subs(x, x_), cond + + raise IntegralTransformError('Inverse Mellin', F, '') + +_allowed = None + + +class InverseMellinTransform(IntegralTransform): + """ + Class representing unevaluated inverse Mellin transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute inverse Mellin transforms, see the + :func:`inverse_mellin_transform` docstring. + """ + + _name = 'Inverse Mellin' + _none_sentinel = Dummy('None') + _c = Dummy('c') + + def __new__(cls, F, s, x, a, b, **opts): + if a is None: + a = InverseMellinTransform._none_sentinel + if b is None: + b = InverseMellinTransform._none_sentinel + return IntegralTransform.__new__(cls, F, s, x, a, b, **opts) + + @property + def fundamental_strip(self): + a, b = self.args[3], self.args[4] + if a is InverseMellinTransform._none_sentinel: + a = None + if b is InverseMellinTransform._none_sentinel: + b = None + return a, b + + def _compute_transform(self, F, s, x, **hints): + # IntegralTransform's doit will cause this hint to exist, but + # InverseMellinTransform should ignore it + hints.pop('simplify', True) + global _allowed + if _allowed is None: + _allowed = { + exp, gamma, sin, cos, tan, cot, cosh, sinh, tanh, coth, + factorial, rf} + for f in postorder_traversal(F): + if f.is_Function and f.has(s) and f.func not in _allowed: + raise IntegralTransformError('Inverse Mellin', F, + 'Component %s not recognised.' % f) + strip = self.fundamental_strip + return _inverse_mellin_transform(F, s, x, strip, **hints) + + def _as_integral(self, F, s, x): + c = self.__class__._c + return Integral(F*x**(-s), (s, c - S.ImaginaryUnit*S.Infinity, c + + S.ImaginaryUnit*S.Infinity))/(2*S.Pi*S.ImaginaryUnit) + + +def inverse_mellin_transform(F, s, x, strip, **hints): + r""" + Compute the inverse Mellin transform of `F(s)` over the fundamental + strip given by ``strip=(a, b)``. + + Explanation + =========== + + This can be defined as + + .. math:: f(x) = \frac{1}{2\pi i} \int_{c - i\infty}^{c + i\infty} x^{-s} F(s) \mathrm{d}s, + + for any `c` in the fundamental strip. Under certain regularity + conditions on `F` and/or `f`, + this recovers `f` from its Mellin transform `F` + (and vice versa), for positive real `x`. + + One of `a` or `b` may be passed as ``None``; a suitable `c` will be + inferred. + + If the integral cannot be computed in closed form, this function returns + an unevaluated :class:`InverseMellinTransform` object. + + Note that this function will assume x to be positive and real, regardless + of the SymPy assumptions! + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + + Examples + ======== + + >>> from sympy import inverse_mellin_transform, oo, gamma + >>> from sympy.abc import x, s + >>> inverse_mellin_transform(gamma(s), s, x, (0, oo)) + exp(-x) + + The fundamental strip matters: + + >>> f = 1/(s**2 - 1) + >>> inverse_mellin_transform(f, s, x, (-oo, -1)) + x*(1 - 1/x**2)*Heaviside(x - 1)/2 + >>> inverse_mellin_transform(f, s, x, (-1, 1)) + -x*Heaviside(1 - x)/2 - Heaviside(x - 1)/(2*x) + >>> inverse_mellin_transform(f, s, x, (1, oo)) + (1/2 - x**2/2)*Heaviside(1 - x)/x + + See Also + ======== + + mellin_transform + hankel_transform, inverse_hankel_transform + """ + return InverseMellinTransform(F, s, x, strip[0], strip[1]).doit(**hints) + + +########################################################################## +# Fourier Transform +########################################################################## + +@_noconds_(True) +def _fourier_transform(f, x, k, a, b, name, simplify=True): + r""" + Compute a general Fourier-type transform + + .. math:: + + F(k) = a \int_{-\infty}^{\infty} e^{bixk} f(x)\, dx. + + For suitable choice of *a* and *b*, this reduces to the standard Fourier + and inverse Fourier transforms. + """ + F = integrate(a*f*exp(b*S.ImaginaryUnit*x*k), (x, S.NegativeInfinity, S.Infinity)) + + if not F.has(Integral): + return _simplify(F, simplify), S.true + + integral_f = integrate(f, (x, S.NegativeInfinity, S.Infinity)) + if integral_f in (S.NegativeInfinity, S.Infinity, S.NaN) or integral_f.has(Integral): + raise IntegralTransformError(name, f, 'function not integrable on real axis') + + if not F.is_Piecewise: + raise IntegralTransformError(name, f, 'could not compute integral') + + F, cond = F.args[0] + if F.has(Integral): + raise IntegralTransformError(name, f, 'integral in unexpected form') + + return _simplify(F, simplify), cond + + +class FourierTypeTransform(IntegralTransform): + """ Base class for Fourier transforms.""" + + def a(self): + raise NotImplementedError( + "Class %s must implement a(self) but does not" % self.__class__) + + def b(self): + raise NotImplementedError( + "Class %s must implement b(self) but does not" % self.__class__) + + def _compute_transform(self, f, x, k, **hints): + return _fourier_transform(f, x, k, + self.a(), self.b(), + self.__class__._name, **hints) + + def _as_integral(self, f, x, k): + a = self.a() + b = self.b() + return Integral(a*f*exp(b*S.ImaginaryUnit*x*k), (x, S.NegativeInfinity, S.Infinity)) + + +class FourierTransform(FourierTypeTransform): + """ + Class representing unevaluated Fourier transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute Fourier transforms, see the :func:`fourier_transform` + docstring. + """ + + _name = 'Fourier' + + def a(self): + return 1 + + def b(self): + return -2*S.Pi + + +def fourier_transform(f, x, k, **hints): + r""" + Compute the unitary, ordinary-frequency Fourier transform of ``f``, defined + as + + .. math:: F(k) = \int_{-\infty}^\infty f(x) e^{-2\pi i x k} \mathrm{d} x. + + Explanation + =========== + + If the transform cannot be computed in closed form, this + function returns an unevaluated :class:`FourierTransform` object. + + For other Fourier transform conventions, see the function + :func:`sympy.integrals.transforms._fourier_transform`. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + Note that for this transform, by default ``noconds=True``. + + Examples + ======== + + >>> from sympy import fourier_transform, exp + >>> from sympy.abc import x, k + >>> fourier_transform(exp(-x**2), x, k) + sqrt(pi)*exp(-pi**2*k**2) + >>> fourier_transform(exp(-x**2), x, k, noconds=False) + (sqrt(pi)*exp(-pi**2*k**2), True) + + See Also + ======== + + inverse_fourier_transform + sine_transform, inverse_sine_transform + cosine_transform, inverse_cosine_transform + hankel_transform, inverse_hankel_transform + mellin_transform, laplace_transform + """ + return FourierTransform(f, x, k).doit(**hints) + + +class InverseFourierTransform(FourierTypeTransform): + """ + Class representing unevaluated inverse Fourier transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute inverse Fourier transforms, see the + :func:`inverse_fourier_transform` docstring. + """ + + _name = 'Inverse Fourier' + + def a(self): + return 1 + + def b(self): + return 2*S.Pi + + +def inverse_fourier_transform(F, k, x, **hints): + r""" + Compute the unitary, ordinary-frequency inverse Fourier transform of `F`, + defined as + + .. math:: f(x) = \int_{-\infty}^\infty F(k) e^{2\pi i x k} \mathrm{d} k. + + Explanation + =========== + + If the transform cannot be computed in closed form, this + function returns an unevaluated :class:`InverseFourierTransform` object. + + For other Fourier transform conventions, see the function + :func:`sympy.integrals.transforms._fourier_transform`. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + Note that for this transform, by default ``noconds=True``. + + Examples + ======== + + >>> from sympy import inverse_fourier_transform, exp, sqrt, pi + >>> from sympy.abc import x, k + >>> inverse_fourier_transform(sqrt(pi)*exp(-(pi*k)**2), k, x) + exp(-x**2) + >>> inverse_fourier_transform(sqrt(pi)*exp(-(pi*k)**2), k, x, noconds=False) + (exp(-x**2), True) + + See Also + ======== + + fourier_transform + sine_transform, inverse_sine_transform + cosine_transform, inverse_cosine_transform + hankel_transform, inverse_hankel_transform + mellin_transform, laplace_transform + """ + return InverseFourierTransform(F, k, x).doit(**hints) + + +########################################################################## +# Fourier Sine and Cosine Transform +########################################################################## + +@_noconds_(True) +def _sine_cosine_transform(f, x, k, a, b, K, name, simplify=True): + """ + Compute a general sine or cosine-type transform + F(k) = a int_0^oo b*sin(x*k) f(x) dx. + F(k) = a int_0^oo b*cos(x*k) f(x) dx. + + For suitable choice of a and b, this reduces to the standard sine/cosine + and inverse sine/cosine transforms. + """ + F = integrate(a*f*K(b*x*k), (x, S.Zero, S.Infinity)) + + if not F.has(Integral): + return _simplify(F, simplify), S.true + + if not F.is_Piecewise: + raise IntegralTransformError(name, f, 'could not compute integral') + + F, cond = F.args[0] + if F.has(Integral): + raise IntegralTransformError(name, f, 'integral in unexpected form') + + return _simplify(F, simplify), cond + + +class SineCosineTypeTransform(IntegralTransform): + """ + Base class for sine and cosine transforms. + Specify cls._kern. + """ + + def a(self): + raise NotImplementedError( + "Class %s must implement a(self) but does not" % self.__class__) + + def b(self): + raise NotImplementedError( + "Class %s must implement b(self) but does not" % self.__class__) + + + def _compute_transform(self, f, x, k, **hints): + return _sine_cosine_transform(f, x, k, + self.a(), self.b(), + self.__class__._kern, + self.__class__._name, **hints) + + def _as_integral(self, f, x, k): + a = self.a() + b = self.b() + K = self.__class__._kern + return Integral(a*f*K(b*x*k), (x, S.Zero, S.Infinity)) + + +class SineTransform(SineCosineTypeTransform): + """ + Class representing unevaluated sine transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute sine transforms, see the :func:`sine_transform` + docstring. + """ + + _name = 'Sine' + _kern = sin + + def a(self): + return sqrt(2)/sqrt(pi) + + def b(self): + return S.One + + +def sine_transform(f, x, k, **hints): + r""" + Compute the unitary, ordinary-frequency sine transform of `f`, defined + as + + .. math:: F(k) = \sqrt{\frac{2}{\pi}} \int_{0}^\infty f(x) \sin(2\pi x k) \mathrm{d} x. + + Explanation + =========== + + If the transform cannot be computed in closed form, this + function returns an unevaluated :class:`SineTransform` object. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + Note that for this transform, by default ``noconds=True``. + + Examples + ======== + + >>> from sympy import sine_transform, exp + >>> from sympy.abc import x, k, a + >>> sine_transform(x*exp(-a*x**2), x, k) + sqrt(2)*k*exp(-k**2/(4*a))/(4*a**(3/2)) + >>> sine_transform(x**(-a), x, k) + 2**(1/2 - a)*k**(a - 1)*gamma(1 - a/2)/gamma(a/2 + 1/2) + + See Also + ======== + + fourier_transform, inverse_fourier_transform + inverse_sine_transform + cosine_transform, inverse_cosine_transform + hankel_transform, inverse_hankel_transform + mellin_transform, laplace_transform + """ + return SineTransform(f, x, k).doit(**hints) + + +class InverseSineTransform(SineCosineTypeTransform): + """ + Class representing unevaluated inverse sine transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute inverse sine transforms, see the + :func:`inverse_sine_transform` docstring. + """ + + _name = 'Inverse Sine' + _kern = sin + + def a(self): + return sqrt(2)/sqrt(pi) + + def b(self): + return S.One + + +def inverse_sine_transform(F, k, x, **hints): + r""" + Compute the unitary, ordinary-frequency inverse sine transform of `F`, + defined as + + .. math:: f(x) = \sqrt{\frac{2}{\pi}} \int_{0}^\infty F(k) \sin(2\pi x k) \mathrm{d} k. + + Explanation + =========== + + If the transform cannot be computed in closed form, this + function returns an unevaluated :class:`InverseSineTransform` object. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + Note that for this transform, by default ``noconds=True``. + + Examples + ======== + + >>> from sympy import inverse_sine_transform, exp, sqrt, gamma + >>> from sympy.abc import x, k, a + >>> inverse_sine_transform(2**((1-2*a)/2)*k**(a - 1)* + ... gamma(-a/2 + 1)/gamma((a+1)/2), k, x) + x**(-a) + >>> inverse_sine_transform(sqrt(2)*k*exp(-k**2/(4*a))/(4*sqrt(a)**3), k, x) + x*exp(-a*x**2) + + See Also + ======== + + fourier_transform, inverse_fourier_transform + sine_transform + cosine_transform, inverse_cosine_transform + hankel_transform, inverse_hankel_transform + mellin_transform, laplace_transform + """ + return InverseSineTransform(F, k, x).doit(**hints) + + +class CosineTransform(SineCosineTypeTransform): + """ + Class representing unevaluated cosine transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute cosine transforms, see the :func:`cosine_transform` + docstring. + """ + + _name = 'Cosine' + _kern = cos + + def a(self): + return sqrt(2)/sqrt(pi) + + def b(self): + return S.One + + +def cosine_transform(f, x, k, **hints): + r""" + Compute the unitary, ordinary-frequency cosine transform of `f`, defined + as + + .. math:: F(k) = \sqrt{\frac{2}{\pi}} \int_{0}^\infty f(x) \cos(2\pi x k) \mathrm{d} x. + + Explanation + =========== + + If the transform cannot be computed in closed form, this + function returns an unevaluated :class:`CosineTransform` object. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + Note that for this transform, by default ``noconds=True``. + + Examples + ======== + + >>> from sympy import cosine_transform, exp, sqrt, cos + >>> from sympy.abc import x, k, a + >>> cosine_transform(exp(-a*x), x, k) + sqrt(2)*a/(sqrt(pi)*(a**2 + k**2)) + >>> cosine_transform(exp(-a*sqrt(x))*cos(a*sqrt(x)), x, k) + a*exp(-a**2/(2*k))/(2*k**(3/2)) + + See Also + ======== + + fourier_transform, inverse_fourier_transform, + sine_transform, inverse_sine_transform + inverse_cosine_transform + hankel_transform, inverse_hankel_transform + mellin_transform, laplace_transform + """ + return CosineTransform(f, x, k).doit(**hints) + + +class InverseCosineTransform(SineCosineTypeTransform): + """ + Class representing unevaluated inverse cosine transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute inverse cosine transforms, see the + :func:`inverse_cosine_transform` docstring. + """ + + _name = 'Inverse Cosine' + _kern = cos + + def a(self): + return sqrt(2)/sqrt(pi) + + def b(self): + return S.One + + +def inverse_cosine_transform(F, k, x, **hints): + r""" + Compute the unitary, ordinary-frequency inverse cosine transform of `F`, + defined as + + .. math:: f(x) = \sqrt{\frac{2}{\pi}} \int_{0}^\infty F(k) \cos(2\pi x k) \mathrm{d} k. + + Explanation + =========== + + If the transform cannot be computed in closed form, this + function returns an unevaluated :class:`InverseCosineTransform` object. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + Note that for this transform, by default ``noconds=True``. + + Examples + ======== + + >>> from sympy import inverse_cosine_transform, sqrt, pi + >>> from sympy.abc import x, k, a + >>> inverse_cosine_transform(sqrt(2)*a/(sqrt(pi)*(a**2 + k**2)), k, x) + exp(-a*x) + >>> inverse_cosine_transform(1/sqrt(k), k, x) + 1/sqrt(x) + + See Also + ======== + + fourier_transform, inverse_fourier_transform, + sine_transform, inverse_sine_transform + cosine_transform + hankel_transform, inverse_hankel_transform + mellin_transform, laplace_transform + """ + return InverseCosineTransform(F, k, x).doit(**hints) + + +########################################################################## +# Hankel Transform +########################################################################## + +@_noconds_(True) +def _hankel_transform(f, r, k, nu, name, simplify=True): + r""" + Compute a general Hankel transform + + .. math:: F_\nu(k) = \int_{0}^\infty f(r) J_\nu(k r) r \mathrm{d} r. + """ + F = integrate(f*besselj(nu, k*r)*r, (r, S.Zero, S.Infinity)) + + if not F.has(Integral): + return _simplify(F, simplify), S.true + + if not F.is_Piecewise: + raise IntegralTransformError(name, f, 'could not compute integral') + + F, cond = F.args[0] + if F.has(Integral): + raise IntegralTransformError(name, f, 'integral in unexpected form') + + return _simplify(F, simplify), cond + + +class HankelTypeTransform(IntegralTransform): + """ + Base class for Hankel transforms. + """ + + def doit(self, **hints): + return self._compute_transform(self.function, + self.function_variable, + self.transform_variable, + self.args[3], + **hints) + + def _compute_transform(self, f, r, k, nu, **hints): + return _hankel_transform(f, r, k, nu, self._name, **hints) + + def _as_integral(self, f, r, k, nu): + return Integral(f*besselj(nu, k*r)*r, (r, S.Zero, S.Infinity)) + + @property + def as_integral(self): + return self._as_integral(self.function, + self.function_variable, + self.transform_variable, + self.args[3]) + + +class HankelTransform(HankelTypeTransform): + """ + Class representing unevaluated Hankel transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute Hankel transforms, see the :func:`hankel_transform` + docstring. + """ + + _name = 'Hankel' + + +def hankel_transform(f, r, k, nu, **hints): + r""" + Compute the Hankel transform of `f`, defined as + + .. math:: F_\nu(k) = \int_{0}^\infty f(r) J_\nu(k r) r \mathrm{d} r. + + Explanation + =========== + + If the transform cannot be computed in closed form, this + function returns an unevaluated :class:`HankelTransform` object. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + Note that for this transform, by default ``noconds=True``. + + Examples + ======== + + >>> from sympy import hankel_transform, inverse_hankel_transform + >>> from sympy import exp + >>> from sympy.abc import r, k, m, nu, a + + >>> ht = hankel_transform(1/r**m, r, k, nu) + >>> ht + 2*k**(m - 2)*gamma(-m/2 + nu/2 + 1)/(2**m*gamma(m/2 + nu/2)) + + >>> inverse_hankel_transform(ht, k, r, nu) + r**(-m) + + >>> ht = hankel_transform(exp(-a*r), r, k, 0) + >>> ht + a/(k**3*(a**2/k**2 + 1)**(3/2)) + + >>> inverse_hankel_transform(ht, k, r, 0) + exp(-a*r) + + See Also + ======== + + fourier_transform, inverse_fourier_transform + sine_transform, inverse_sine_transform + cosine_transform, inverse_cosine_transform + inverse_hankel_transform + mellin_transform, laplace_transform + """ + return HankelTransform(f, r, k, nu).doit(**hints) + + +class InverseHankelTransform(HankelTypeTransform): + """ + Class representing unevaluated inverse Hankel transforms. + + For usage of this class, see the :class:`IntegralTransform` docstring. + + For how to compute inverse Hankel transforms, see the + :func:`inverse_hankel_transform` docstring. + """ + + _name = 'Inverse Hankel' + + +def inverse_hankel_transform(F, k, r, nu, **hints): + r""" + Compute the inverse Hankel transform of `F` defined as + + .. math:: f(r) = \int_{0}^\infty F_\nu(k) J_\nu(k r) k \mathrm{d} k. + + Explanation + =========== + + If the transform cannot be computed in closed form, this + function returns an unevaluated :class:`InverseHankelTransform` object. + + For a description of possible hints, refer to the docstring of + :func:`sympy.integrals.transforms.IntegralTransform.doit`. + Note that for this transform, by default ``noconds=True``. + + Examples + ======== + + >>> from sympy import hankel_transform, inverse_hankel_transform + >>> from sympy import exp + >>> from sympy.abc import r, k, m, nu, a + + >>> ht = hankel_transform(1/r**m, r, k, nu) + >>> ht + 2*k**(m - 2)*gamma(-m/2 + nu/2 + 1)/(2**m*gamma(m/2 + nu/2)) + + >>> inverse_hankel_transform(ht, k, r, nu) + r**(-m) + + >>> ht = hankel_transform(exp(-a*r), r, k, 0) + >>> ht + a/(k**3*(a**2/k**2 + 1)**(3/2)) + + >>> inverse_hankel_transform(ht, k, r, 0) + exp(-a*r) + + See Also + ======== + + fourier_transform, inverse_fourier_transform + sine_transform, inverse_sine_transform + cosine_transform, inverse_cosine_transform + hankel_transform + mellin_transform, laplace_transform + """ + return InverseHankelTransform(F, k, r, nu).doit(**hints) + + +########################################################################## +# Laplace Transform +########################################################################## + +# Stub classes and functions that used to be here +import sympy.integrals.laplace as _laplace + +LaplaceTransform = _laplace.LaplaceTransform +laplace_transform = _laplace.laplace_transform +laplace_correspondence = _laplace.laplace_correspondence +laplace_initial_conds = _laplace.laplace_initial_conds +InverseLaplaceTransform = _laplace.InverseLaplaceTransform +inverse_laplace_transform = _laplace.inverse_laplace_transform diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/trigonometry.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/trigonometry.py new file mode 100644 index 0000000000000000000000000000000000000000..dd6389bcc79f28ed6c255546685da1a0e061c327 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/integrals/trigonometry.py @@ -0,0 +1,335 @@ +from sympy.core import cacheit, Dummy, Ne, Integer, Rational, S, Wild +from sympy.functions import binomial, sin, cos, Piecewise, Abs +from .integrals import integrate + +# TODO sin(a*x)*cos(b*x) -> sin((a+b)x) + sin((a-b)x) ? + +# creating, each time, Wild's and sin/cos/Mul is expensive. Also, our match & +# subs are very slow when not cached, and if we create Wild each time, we +# effectively block caching. +# +# so we cache the pattern + +# need to use a function instead of lamda since hash of lambda changes on +# each call to _pat_sincos +def _integer_instance(n): + return isinstance(n, Integer) + +@cacheit +def _pat_sincos(x): + a = Wild('a', exclude=[x]) + n, m = [Wild(s, exclude=[x], properties=[_integer_instance]) + for s in 'nm'] + pat = sin(a*x)**n * cos(a*x)**m + return pat, a, n, m + +_u = Dummy('u') + + +def trigintegrate(f, x, conds='piecewise'): + """ + Integrate f = Mul(trig) over x. + + Examples + ======== + + >>> from sympy import sin, cos, tan, sec + >>> from sympy.integrals.trigonometry import trigintegrate + >>> from sympy.abc import x + + >>> trigintegrate(sin(x)*cos(x), x) + sin(x)**2/2 + + >>> trigintegrate(sin(x)**2, x) + x/2 - sin(x)*cos(x)/2 + + >>> trigintegrate(tan(x)*sec(x), x) + 1/cos(x) + + >>> trigintegrate(sin(x)*tan(x), x) + -log(sin(x) - 1)/2 + log(sin(x) + 1)/2 - sin(x) + + References + ========== + + .. [1] https://en.wikibooks.org/wiki/Calculus/Integration_techniques + + See Also + ======== + + sympy.integrals.integrals.Integral.doit + sympy.integrals.integrals.Integral + """ + pat, a, n, m = _pat_sincos(x) + + f = f.rewrite('sincos') + M = f.match(pat) + + if M is None: + return + + n, m = M[n], M[m] + if n.is_zero and m.is_zero: + return x + zz = x if n.is_zero else S.Zero + + a = M[a] + + if n.is_odd or m.is_odd: + u = _u + n_, m_ = n.is_odd, m.is_odd + + # take smallest n or m -- to choose simplest substitution + if n_ and m_: + + # Make sure to choose the positive one + # otherwise an incorrect integral can occur. + if n < 0 and m > 0: + m_ = True + n_ = False + elif m < 0 and n > 0: + n_ = True + m_ = False + # Both are negative so choose the smallest n or m + # in absolute value for simplest substitution. + elif (n < 0 and m < 0): + n_ = n > m + m_ = not (n > m) + + # Both n and m are odd and positive + else: + n_ = (n < m) # NB: careful here, one of the + m_ = not (n < m) # conditions *must* be true + + # n m u=C (n-1)/2 m + # S(x) * C(x) dx --> -(1-u^2) * u du + if n_: + ff = -(1 - u**2)**((n - 1)/2) * u**m + uu = cos(a*x) + + # n m u=S n (m-1)/2 + # S(x) * C(x) dx --> u * (1-u^2) du + elif m_: + ff = u**n * (1 - u**2)**((m - 1)/2) + uu = sin(a*x) + + fi = integrate(ff, u) # XXX cyclic deps + fx = fi.subs(u, uu) + if conds == 'piecewise': + return Piecewise((fx / a, Ne(a, 0)), (zz, True)) + return fx / a + + # n & m are both even + # + # 2k 2m 2l 2l + # we transform S (x) * C (x) into terms with only S (x) or C (x) + # + # example: + # 100 4 100 2 2 100 4 2 + # S (x) * C (x) = S (x) * (1-S (x)) = S (x) * (1 + S (x) - 2*S (x)) + # + # 104 102 100 + # = S (x) - 2*S (x) + S (x) + # 2k + # then S is integrated with recursive formula + + # take largest n or m -- to choose simplest substitution + n_ = (Abs(n) > Abs(m)) + m_ = (Abs(m) > Abs(n)) + res = S.Zero + + if n_: + # 2k 2 k i 2i + # C = (1 - S ) = sum(i, (-) * B(k, i) * S ) + if m > 0: + for i in range(0, m//2 + 1): + res += (S.NegativeOne**i * binomial(m//2, i) * + _sin_pow_integrate(n + 2*i, x)) + + elif m == 0: + res = _sin_pow_integrate(n, x) + else: + + # m < 0 , |n| > |m| + # / + # | + # | m n + # | cos (x) sin (x) dx = + # | + # | + #/ + # / + # | + # -1 m+1 n-1 n - 1 | m+2 n-2 + # ________ cos (x) sin (x) + _______ | cos (x) sin (x) dx + # | + # m + 1 m + 1 | + # / + + res = (Rational(-1, m + 1) * cos(x)**(m + 1) * sin(x)**(n - 1) + + Rational(n - 1, m + 1) * + trigintegrate(cos(x)**(m + 2)*sin(x)**(n - 2), x)) + + elif m_: + # 2k 2 k i 2i + # S = (1 - C ) = sum(i, (-) * B(k, i) * C ) + if n > 0: + + # / / + # | | + # | m n | -m n + # | cos (x)*sin (x) dx or | cos (x) * sin (x) dx + # | | + # / / + # + # |m| > |n| ; m, n >0 ; m, n belong to Z - {0} + # n 2 + # sin (x) term is expanded here in terms of cos (x), + # and then integrated. + # + + for i in range(0, n//2 + 1): + res += (S.NegativeOne**i * binomial(n//2, i) * + _cos_pow_integrate(m + 2*i, x)) + + elif n == 0: + + # / + # | + # | 1 + # | _ _ _ + # | m + # | cos (x) + # / + # + + res = _cos_pow_integrate(m, x) + else: + + # n < 0 , |m| > |n| + # / + # | + # | m n + # | cos (x) sin (x) dx = + # | + # | + #/ + # / + # | + # 1 m-1 n+1 m - 1 | m-2 n+2 + # _______ cos (x) sin (x) + _______ | cos (x) sin (x) dx + # | + # n + 1 n + 1 | + # / + + res = (Rational(1, n + 1) * cos(x)**(m - 1)*sin(x)**(n + 1) + + Rational(m - 1, n + 1) * + trigintegrate(cos(x)**(m - 2)*sin(x)**(n + 2), x)) + + else: + if m == n: + ##Substitute sin(2x)/2 for sin(x)cos(x) and then Integrate. + res = integrate((sin(2*x)*S.Half)**m, x) + elif (m == -n): + if n < 0: + # Same as the scheme described above. + # the function argument to integrate in the end will + # be 1, this cannot be integrated by trigintegrate. + # Hence use sympy.integrals.integrate. + res = (Rational(1, n + 1) * cos(x)**(m - 1) * sin(x)**(n + 1) + + Rational(m - 1, n + 1) * + integrate(cos(x)**(m - 2) * sin(x)**(n + 2), x)) + else: + res = (Rational(-1, m + 1) * cos(x)**(m + 1) * sin(x)**(n - 1) + + Rational(n - 1, m + 1) * + integrate(cos(x)**(m + 2)*sin(x)**(n - 2), x)) + if conds == 'piecewise': + return Piecewise((res.subs(x, a*x) / a, Ne(a, 0)), (zz, True)) + return res.subs(x, a*x) / a + + +def _sin_pow_integrate(n, x): + if n > 0: + if n == 1: + #Recursion break + return -cos(x) + + # n > 0 + # / / + # | | + # | n -1 n-1 n - 1 | n-2 + # | sin (x) dx = ______ cos (x) sin (x) + _______ | sin (x) dx + # | | + # | n n | + #/ / + # + # + + return (Rational(-1, n) * cos(x) * sin(x)**(n - 1) + + Rational(n - 1, n) * _sin_pow_integrate(n - 2, x)) + + if n < 0: + if n == -1: + ##Make sure this does not come back here again. + ##Recursion breaks here or at n==0. + return trigintegrate(1/sin(x), x) + + # n < 0 + # / / + # | | + # | n 1 n+1 n + 2 | n+2 + # | sin (x) dx = _______ cos (x) sin (x) + _______ | sin (x) dx + # | | + # | n + 1 n + 1 | + #/ / + # + + return (Rational(1, n + 1) * cos(x) * sin(x)**(n + 1) + + Rational(n + 2, n + 1) * _sin_pow_integrate(n + 2, x)) + + else: + #n == 0 + #Recursion break. + return x + + +def _cos_pow_integrate(n, x): + if n > 0: + if n == 1: + #Recursion break. + return sin(x) + + # n > 0 + # / / + # | | + # | n 1 n-1 n - 1 | n-2 + # | sin (x) dx = ______ sin (x) cos (x) + _______ | cos (x) dx + # | | + # | n n | + #/ / + # + + return (Rational(1, n) * sin(x) * cos(x)**(n - 1) + + Rational(n - 1, n) * _cos_pow_integrate(n - 2, x)) + + if n < 0: + if n == -1: + ##Recursion break + return trigintegrate(1/cos(x), x) + + # n < 0 + # / / + # | | + # | n -1 n+1 n + 2 | n+2 + # | cos (x) dx = _______ sin (x) cos (x) + _______ | cos (x) dx + # | | + # | n + 1 n + 1 | + #/ / + # + + return (Rational(-1, n + 1) * sin(x) * cos(x)**(n + 1) + + Rational(n + 2, n + 1) * _cos_pow_integrate(n + 2, x)) + else: + # n == 0 + #Recursion Break. + return x diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..1b3f043ada6222d79dd52fd28b035e2ea45c5683 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/__init__.py @@ -0,0 +1,8 @@ +"""Helper module for setting up interactive SymPy sessions. """ + +from .printing import init_printing +from .session import init_session +from .traversal import interactive_traversal + + +__all__ = ['init_printing', 'init_session', 'interactive_traversal'] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/printing.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/printing.py new file mode 100644 index 0000000000000000000000000000000000000000..2fcc73e3e96a5b7e25f7fc7ebf54a5781c3b15b9 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/printing.py @@ -0,0 +1,532 @@ +"""Tools for setting up printing in interactive sessions. """ + +from io import BytesIO + +from sympy.printing.latex import latex as default_latex +from sympy.printing.preview import preview +from sympy.utilities.misc import debug +from sympy.printing.defaults import Printable +from sympy.external import import_module + + +def _init_python_printing(stringify_func, **settings): + """Setup printing in Python interactive session. """ + import sys + import builtins + + def _displayhook(arg): + """Python's pretty-printer display hook. + + This function was adapted from: + + https://www.python.org/dev/peps/pep-0217/ + + """ + if arg is not None: + builtins._ = None + print(stringify_func(arg, **settings)) + builtins._ = arg + + sys.displayhook = _displayhook + + +def _init_ipython_printing(ip, stringify_func, use_latex, euler, forecolor, + backcolor, fontsize, latex_mode, print_builtin, + latex_printer, scale, **settings): + """Setup printing in IPython interactive session. """ + IPython = import_module("IPython", min_module_version="1.0") + try: + from IPython.lib.latextools import latex_to_png + except ImportError: + pass + + # Guess best font color if none was given based on the ip.colors string. + # From the IPython documentation: + # It has four case-insensitive values: 'nocolor', 'neutral', 'linux', + # 'lightbg'. The default is neutral, which should be legible on either + # dark or light terminal backgrounds. linux is optimised for dark + # backgrounds and lightbg for light ones. + if forecolor is None: + color = ip.colors.lower() + if color == 'lightbg': + forecolor = 'Black' + elif color == 'linux': + forecolor = 'White' + else: + # No idea, go with gray. + forecolor = 'Gray' + debug("init_printing: Automatic foreground color:", forecolor) + + if use_latex == "svg": + extra_preamble = "\n\\special{color %s}" % forecolor + else: + extra_preamble = "" + + imagesize = 'tight' + offset = "0cm,0cm" + resolution = round(150*scale) + dvi = r"-T %s -D %d -bg %s -fg %s -O %s" % ( + imagesize, resolution, backcolor, forecolor, offset) + dvioptions = dvi.split() + + svg_scale = 150/72*scale + dvioptions_svg = ["--no-fonts", "--scale={}".format(svg_scale)] + + debug("init_printing: DVIOPTIONS:", dvioptions) + debug("init_printing: DVIOPTIONS_SVG:", dvioptions_svg) + + latex = latex_printer or default_latex + + def _print_plain(arg, p, cycle): + """caller for pretty, for use in IPython 0.11""" + if _can_print(arg): + p.text(stringify_func(arg)) + else: + p.text(IPython.lib.pretty.pretty(arg)) + + def _preview_wrapper(o): + exprbuffer = BytesIO() + try: + preview(o, output='png', viewer='BytesIO', euler=euler, + outputbuffer=exprbuffer, extra_preamble=extra_preamble, + dvioptions=dvioptions, fontsize=fontsize) + except Exception as e: + # IPython swallows exceptions + debug("png printing:", "_preview_wrapper exception raised:", + repr(e)) + raise + return exprbuffer.getvalue() + + def _svg_wrapper(o): + exprbuffer = BytesIO() + try: + preview(o, output='svg', viewer='BytesIO', euler=euler, + outputbuffer=exprbuffer, extra_preamble=extra_preamble, + dvioptions=dvioptions_svg, fontsize=fontsize) + except Exception as e: + # IPython swallows exceptions + debug("svg printing:", "_preview_wrapper exception raised:", + repr(e)) + raise + return exprbuffer.getvalue().decode('utf-8') + + def _matplotlib_wrapper(o): + # mathtext can't render some LaTeX commands. For example, it can't + # render any LaTeX environments such as array or matrix. So here we + # ensure that if mathtext fails to render, we return None. + try: + try: + return latex_to_png(o, color=forecolor, scale=scale) + except TypeError: # Old IPython version without color and scale + return latex_to_png(o) + except ValueError as e: + debug('matplotlib exception caught:', repr(e)) + return None + + + # Hook methods for builtin SymPy printers + printing_hooks = ('_latex', '_sympystr', '_pretty', '_sympyrepr') + + + def _can_print(o): + """Return True if type o can be printed with one of the SymPy printers. + + If o is a container type, this is True if and only if every element of + o can be printed in this way. + """ + + try: + # If you're adding another type, make sure you add it to printable_types + # later in this file as well + + builtin_types = (list, tuple, set, frozenset) + if isinstance(o, builtin_types): + # If the object is a custom subclass with a custom str or + # repr, use that instead. + if (type(o).__str__ not in (i.__str__ for i in builtin_types) or + type(o).__repr__ not in (i.__repr__ for i in builtin_types)): + return False + return all(_can_print(i) for i in o) + elif isinstance(o, dict): + return all(_can_print(i) and _can_print(o[i]) for i in o) + elif isinstance(o, bool): + return False + elif isinstance(o, Printable): + # types known to SymPy + return True + elif any(hasattr(o, hook) for hook in printing_hooks): + # types which add support themselves + return True + elif isinstance(o, (float, int)) and print_builtin: + return True + return False + except RuntimeError: + return False + # This is in case maximum recursion depth is reached. + # Since RecursionError is for versions of Python 3.5+ + # so this is to guard against RecursionError for older versions. + + def _print_latex_png(o): + """ + A function that returns a png rendered by an external latex + distribution, falling back to matplotlib rendering + """ + if _can_print(o): + s = latex(o, mode=latex_mode, **settings) + if latex_mode == 'plain': + s = '$\\displaystyle %s$' % s + try: + return _preview_wrapper(s) + except RuntimeError as e: + debug('preview failed with:', repr(e), + ' Falling back to matplotlib backend') + if latex_mode != 'inline': + s = latex(o, mode='inline', **settings) + return _matplotlib_wrapper(s) + + def _print_latex_svg(o): + """ + A function that returns a svg rendered by an external latex + distribution, no fallback available. + """ + if _can_print(o): + s = latex(o, mode=latex_mode, **settings) + if latex_mode == 'plain': + s = '$\\displaystyle %s$' % s + try: + return _svg_wrapper(s) + except RuntimeError as e: + debug('preview failed with:', repr(e), + ' No fallback available.') + + def _print_latex_matplotlib(o): + """ + A function that returns a png rendered by mathtext + """ + if _can_print(o): + s = latex(o, mode='inline', **settings) + return _matplotlib_wrapper(s) + + def _print_latex_text(o): + """ + A function to generate the latex representation of SymPy expressions. + """ + if _can_print(o): + s = latex(o, mode=latex_mode, **settings) + if latex_mode == 'plain': + return '$\\displaystyle %s$' % s + return s + + # Printable is our own type, so we handle it with methods instead of + # the approach required by builtin types. This allows downstream + # packages to override the methods in their own subclasses of Printable, + # which avoids the effects of gh-16002. + printable_types = [float, tuple, list, set, frozenset, dict, int] + + plaintext_formatter = ip.display_formatter.formatters['text/plain'] + + # Exception to the rule above: IPython has better dispatching rules + # for plaintext printing (xref ipython/ipython#8938), and we can't + # use `_repr_pretty_` without hitting a recursion error in _print_plain. + for cls in printable_types + [Printable]: + plaintext_formatter.for_type(cls, _print_plain) + + svg_formatter = ip.display_formatter.formatters['image/svg+xml'] + if use_latex in ('svg', ): + debug("init_printing: using svg formatter") + for cls in printable_types: + svg_formatter.for_type(cls, _print_latex_svg) + Printable._repr_svg_ = _print_latex_svg + else: + debug("init_printing: not using any svg formatter") + for cls in printable_types: + # Better way to set this, but currently does not work in IPython + #png_formatter.for_type(cls, None) + if cls in svg_formatter.type_printers: + svg_formatter.type_printers.pop(cls) + Printable._repr_svg_ = Printable._repr_disabled + + png_formatter = ip.display_formatter.formatters['image/png'] + if use_latex in (True, 'png'): + debug("init_printing: using png formatter") + for cls in printable_types: + png_formatter.for_type(cls, _print_latex_png) + Printable._repr_png_ = _print_latex_png + elif use_latex == 'matplotlib': + debug("init_printing: using matplotlib formatter") + for cls in printable_types: + png_formatter.for_type(cls, _print_latex_matplotlib) + Printable._repr_png_ = _print_latex_matplotlib + else: + debug("init_printing: not using any png formatter") + for cls in printable_types: + # Better way to set this, but currently does not work in IPython + #png_formatter.for_type(cls, None) + if cls in png_formatter.type_printers: + png_formatter.type_printers.pop(cls) + Printable._repr_png_ = Printable._repr_disabled + + latex_formatter = ip.display_formatter.formatters['text/latex'] + if use_latex in (True, 'mathjax'): + debug("init_printing: using mathjax formatter") + for cls in printable_types: + latex_formatter.for_type(cls, _print_latex_text) + Printable._repr_latex_ = _print_latex_text + else: + debug("init_printing: not using text/latex formatter") + for cls in printable_types: + # Better way to set this, but currently does not work in IPython + #latex_formatter.for_type(cls, None) + if cls in latex_formatter.type_printers: + latex_formatter.type_printers.pop(cls) + Printable._repr_latex_ = Printable._repr_disabled + +def _is_ipython(shell): + """Is a shell instance an IPython shell?""" + # shortcut, so we don't import IPython if we don't have to + from sys import modules + if 'IPython' not in modules: + return False + try: + from IPython.core.interactiveshell import InteractiveShell + except ImportError: + # IPython < 0.11 + try: + from IPython.iplib import InteractiveShell + except ImportError: + # Reaching this points means IPython has changed in a backward-incompatible way + # that we don't know about. Warn? + return False + return isinstance(shell, InteractiveShell) + +# Used by the doctester to override the default for no_global +NO_GLOBAL = False + +def init_printing(pretty_print=True, order=None, use_unicode=None, + use_latex=None, wrap_line=None, num_columns=None, + no_global=False, ip=None, euler=False, forecolor=None, + backcolor='Transparent', fontsize='10pt', + latex_mode='plain', print_builtin=True, + str_printer=None, pretty_printer=None, + latex_printer=None, scale=1.0, **settings): + r""" + Initializes pretty-printer depending on the environment. + + Parameters + ========== + + pretty_print : bool, default=True + If ``True``, use :func:`~.pretty_print` to stringify or the provided pretty + printer; if ``False``, use :func:`~.sstrrepr` to stringify or the provided string + printer. + order : string or None, default='lex' + There are a few different settings for this parameter: + ``'lex'`` (default), which is lexographic order; + ``'grlex'``, which is graded lexographic order; + ``'grevlex'``, which is reversed graded lexographic order; + ``'old'``, which is used for compatibility reasons and for long expressions; + ``None``, which sets it to lex. + use_unicode : bool or None, default=None + If ``True``, use unicode characters; + if ``False``, do not use unicode characters; + if ``None``, make a guess based on the environment. + use_latex : string, bool, or None, default=None + If ``True``, use default LaTeX rendering in GUI interfaces (png and + mathjax); + if ``False``, do not use LaTeX rendering; + if ``None``, make a guess based on the environment; + if ``'png'``, enable LaTeX rendering with an external LaTeX compiler, + falling back to matplotlib if external compilation fails; + if ``'matplotlib'``, enable LaTeX rendering with matplotlib; + if ``'mathjax'``, enable LaTeX text generation, for example MathJax + rendering in IPython notebook or text rendering in LaTeX documents; + if ``'svg'``, enable LaTeX rendering with an external latex compiler, + no fallback + wrap_line : bool + If True, lines will wrap at the end; if False, they will not wrap + but continue as one line. This is only relevant if ``pretty_print`` is + True. + num_columns : int or None, default=None + If ``int``, number of columns before wrapping is set to num_columns; if + ``None``, number of columns before wrapping is set to terminal width. + This is only relevant if ``pretty_print`` is ``True``. + no_global : bool, default=False + If ``True``, the settings become system wide; + if ``False``, use just for this console/session. + ip : An interactive console + This can either be an instance of IPython, + or a class that derives from code.InteractiveConsole. + euler : bool, optional, default=False + Loads the euler package in the LaTeX preamble for handwritten style + fonts (https://www.ctan.org/pkg/euler). + forecolor : string or None, optional, default=None + DVI setting for foreground color. ``None`` means that either ``'Black'``, + ``'White'``, or ``'Gray'`` will be selected based on a guess of the IPython + terminal color setting. See notes. + backcolor : string, optional, default='Transparent' + DVI setting for background color. See notes. + fontsize : string or int, optional, default='10pt' + A font size to pass to the LaTeX documentclass function in the + preamble. Note that the options are limited by the documentclass. + Consider using scale instead. + latex_mode : string, optional, default='plain' + The mode used in the LaTeX printer. Can be one of: + ``{'inline'|'plain'|'equation'|'equation*'}``. + print_builtin : boolean, optional, default=True + If ``True`` then floats and integers will be printed. If ``False`` the + printer will only print SymPy types. + str_printer : function, optional, default=None + A custom string printer function. This should mimic + :func:`~.sstrrepr`. + pretty_printer : function, optional, default=None + A custom pretty printer. This should mimic :func:`~.pretty`. + latex_printer : function, optional, default=None + A custom LaTeX printer. This should mimic :func:`~.latex`. + scale : float, optional, default=1.0 + Scale the LaTeX output when using the ``'png'`` or ``'svg'`` backends. + Useful for high dpi screens. + settings : + Any additional settings for the ``latex`` and ``pretty`` commands can + be used to fine-tune the output. + + Examples + ======== + + >>> from sympy.interactive import init_printing + >>> from sympy import Symbol, sqrt + >>> from sympy.abc import x, y + >>> sqrt(5) + sqrt(5) + >>> init_printing(pretty_print=True) # doctest: +SKIP + >>> sqrt(5) # doctest: +SKIP + ___ + \/ 5 + >>> theta = Symbol('theta') # doctest: +SKIP + >>> init_printing(use_unicode=True) # doctest: +SKIP + >>> theta # doctest: +SKIP + \u03b8 + >>> init_printing(use_unicode=False) # doctest: +SKIP + >>> theta # doctest: +SKIP + theta + >>> init_printing(order='lex') # doctest: +SKIP + >>> str(y + x + y**2 + x**2) # doctest: +SKIP + x**2 + x + y**2 + y + >>> init_printing(order='grlex') # doctest: +SKIP + >>> str(y + x + y**2 + x**2) # doctest: +SKIP + x**2 + x + y**2 + y + >>> init_printing(order='grevlex') # doctest: +SKIP + >>> str(y * x**2 + x * y**2) # doctest: +SKIP + x**2*y + x*y**2 + >>> init_printing(order='old') # doctest: +SKIP + >>> str(x**2 + y**2 + x + y) # doctest: +SKIP + x**2 + x + y**2 + y + >>> init_printing(num_columns=10) # doctest: +SKIP + >>> x**2 + x + y**2 + y # doctest: +SKIP + x + y + + x**2 + y**2 + + Notes + ===== + + The foreground and background colors can be selected when using ``'png'`` or + ``'svg'`` LaTeX rendering. Note that before the ``init_printing`` command is + executed, the LaTeX rendering is handled by the IPython console and not SymPy. + + The colors can be selected among the 68 standard colors known to ``dvips``, + for a list see [1]_. In addition, the background color can be + set to ``'Transparent'`` (which is the default value). + + When using the ``'Auto'`` foreground color, the guess is based on the + ``colors`` variable in the IPython console, see [2]_. Hence, if + that variable is set correctly in your IPython console, there is a high + chance that the output will be readable, although manual settings may be + needed. + + + References + ========== + + .. [1] https://en.wikibooks.org/wiki/LaTeX/Colors#The_68_standard_colors_known_to_dvips + + .. [2] https://ipython.readthedocs.io/en/stable/config/details.html#terminal-colors + + See Also + ======== + + sympy.printing.latex + sympy.printing.pretty + + """ + import sys + from sympy.printing.printer import Printer + + if pretty_print: + if pretty_printer is not None: + stringify_func = pretty_printer + else: + from sympy.printing import pretty as stringify_func + else: + if str_printer is not None: + stringify_func = str_printer + else: + from sympy.printing import sstrrepr as stringify_func + + # Even if ip is not passed, double check that not in IPython shell + in_ipython = False + if ip is None: + try: + ip = get_ipython() + except NameError: + pass + else: + in_ipython = (ip is not None) + + if ip and not in_ipython: + in_ipython = _is_ipython(ip) + + if in_ipython and pretty_print: + try: + from IPython.terminal.interactiveshell import TerminalInteractiveShell + from code import InteractiveConsole + except ImportError: + pass + else: + # This will be True if we are in the qtconsole or notebook + if not isinstance(ip, (InteractiveConsole, TerminalInteractiveShell)) \ + and 'ipython-console' not in ''.join(sys.argv): + if use_unicode is None: + debug("init_printing: Setting use_unicode to True") + use_unicode = True + if use_latex is None: + debug("init_printing: Setting use_latex to True") + use_latex = True + + if not NO_GLOBAL and not no_global: + Printer.set_global_settings(order=order, use_unicode=use_unicode, + wrap_line=wrap_line, num_columns=num_columns) + else: + _stringify_func = stringify_func + + if pretty_print: + stringify_func = lambda expr, **settings: \ + _stringify_func(expr, order=order, + use_unicode=use_unicode, + wrap_line=wrap_line, + num_columns=num_columns, + **settings) + else: + stringify_func = \ + lambda expr, **settings: _stringify_func( + expr, order=order, **settings) + + if in_ipython: + mode_in_settings = settings.pop("mode", None) + if mode_in_settings: + debug("init_printing: Mode is not able to be set due to internals" + "of IPython printing") + _init_ipython_printing(ip, stringify_func, use_latex, euler, + forecolor, backcolor, fontsize, latex_mode, + print_builtin, latex_printer, scale, + **settings) + else: + _init_python_printing(stringify_func, **settings) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/session.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/session.py new file mode 100644 index 0000000000000000000000000000000000000000..348b0938d69e5e7ffa9510f7d9ac759eb6683b8f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/session.py @@ -0,0 +1,463 @@ +"""Tools for setting up interactive sessions. """ + +from sympy.external.gmpy import GROUND_TYPES +from sympy.external.importtools import version_tuple + +from sympy.interactive.printing import init_printing + +from sympy.utilities.misc import ARCH + +preexec_source = """\ +from sympy import * +x, y, z, t = symbols('x y z t') +k, m, n = symbols('k m n', integer=True) +f, g, h = symbols('f g h', cls=Function) +init_printing() +""" + +verbose_message = """\ +These commands were executed: +%(source)s +Documentation can be found at https://docs.sympy.org/%(version)s +""" + +no_ipython = """\ +Could not locate IPython. Having IPython installed is greatly recommended. +See http://ipython.scipy.org for more details. If you use Debian/Ubuntu, +just install the 'ipython' package and start isympy again. +""" + + +def _make_message(ipython=True, quiet=False, source=None): + """Create a banner for an interactive session. """ + from sympy import __version__ as sympy_version + from sympy import SYMPY_DEBUG + + import sys + import os + + if quiet: + return "" + + python_version = "%d.%d.%d" % sys.version_info[:3] + + if ipython: + shell_name = "IPython" + else: + shell_name = "Python" + + info = ['ground types: %s' % GROUND_TYPES] + + cache = os.getenv('SYMPY_USE_CACHE') + + if cache is not None and cache.lower() == 'no': + info.append('cache: off') + + if SYMPY_DEBUG: + info.append('debugging: on') + + args = shell_name, sympy_version, python_version, ARCH, ', '.join(info) + message = "%s console for SymPy %s (Python %s-%s) (%s)\n" % args + + if source is None: + source = preexec_source + + _source = "" + + for line in source.split('\n')[:-1]: + if not line: + _source += '\n' + else: + _source += '>>> ' + line + '\n' + + doc_version = sympy_version + if 'dev' in doc_version: + doc_version = "dev" + else: + doc_version = "%s/" % doc_version + + message += '\n' + verbose_message % {'source': _source, + 'version': doc_version} + + return message + + +def int_to_Integer(s): + """ + Wrap integer literals with Integer. + + This is based on the decistmt example from + https://docs.python.org/3/library/tokenize.html. + + Only integer literals are converted. Float literals are left alone. + + Examples + ======== + + >>> from sympy import Integer # noqa: F401 + >>> from sympy.interactive.session import int_to_Integer + >>> s = '1.2 + 1/2 - 0x12 + a1' + >>> int_to_Integer(s) + '1.2 +Integer (1 )/Integer (2 )-Integer (0x12 )+a1 ' + >>> s = 'print (1/2)' + >>> int_to_Integer(s) + 'print (Integer (1 )/Integer (2 ))' + >>> exec(s) + 0.5 + >>> exec(int_to_Integer(s)) + 1/2 + """ + from tokenize import generate_tokens, untokenize, NUMBER, NAME, OP + from io import StringIO + + def _is_int(num): + """ + Returns true if string value num (with token NUMBER) represents an integer. + """ + # XXX: Is there something in the standard library that will do this? + if '.' in num or 'j' in num.lower() or 'e' in num.lower(): + return False + return True + + result = [] + g = generate_tokens(StringIO(s).readline) # tokenize the string + for toknum, tokval, _, _, _ in g: + if toknum == NUMBER and _is_int(tokval): # replace NUMBER tokens + result.extend([ + (NAME, 'Integer'), + (OP, '('), + (NUMBER, tokval), + (OP, ')') + ]) + else: + result.append((toknum, tokval)) + return untokenize(result) + + +def enable_automatic_int_sympification(shell): + """ + Allow IPython to automatically convert integer literals to Integer. + """ + import ast + old_run_cell = shell.run_cell + + def my_run_cell(cell, *args, **kwargs): + try: + # Check the cell for syntax errors. This way, the syntax error + # will show the original input, not the transformed input. The + # downside here is that IPython magic like %timeit will not work + # with transformed input (but on the other hand, IPython magic + # that doesn't expect transformed input will continue to work). + ast.parse(cell) + except SyntaxError: + pass + else: + cell = int_to_Integer(cell) + return old_run_cell(cell, *args, **kwargs) + + shell.run_cell = my_run_cell + + +def enable_automatic_symbols(shell): + """Allow IPython to automatically create symbols (``isympy -a``). """ + # XXX: This should perhaps use tokenize, like int_to_Integer() above. + # This would avoid re-executing the code, which can lead to subtle + # issues. For example: + # + # In [1]: a = 1 + # + # In [2]: for i in range(10): + # ...: a += 1 + # ...: + # + # In [3]: a + # Out[3]: 11 + # + # In [4]: a = 1 + # + # In [5]: for i in range(10): + # ...: a += 1 + # ...: print b + # ...: + # b + # b + # b + # b + # b + # b + # b + # b + # b + # b + # + # In [6]: a + # Out[6]: 12 + # + # Note how the for loop is executed again because `b` was not defined, but `a` + # was already incremented once, so the result is that it is incremented + # multiple times. + + import re + re_nameerror = re.compile( + "name '(?P[A-Za-z_][A-Za-z0-9_]*)' is not defined") + + def _handler(self, etype, value, tb, tb_offset=None): + """Handle :exc:`NameError` exception and allow injection of missing symbols. """ + if etype is NameError and tb.tb_next and not tb.tb_next.tb_next: + match = re_nameerror.match(str(value)) + + if match is not None: + # XXX: Make sure Symbol is in scope. Otherwise you'll get infinite recursion. + self.run_cell("%(symbol)s = Symbol('%(symbol)s')" % + {'symbol': match.group("symbol")}, store_history=False) + + try: + code = self.user_ns['In'][-1] + except (KeyError, IndexError): + pass + else: + self.run_cell(code, store_history=False) + return None + finally: + self.run_cell("del %s" % match.group("symbol"), + store_history=False) + + stb = self.InteractiveTB.structured_traceback( + etype, value, tb, tb_offset=tb_offset) + self._showtraceback(etype, value, stb) + + shell.set_custom_exc((NameError,), _handler) + + +def init_ipython_session(shell=None, argv=[], auto_symbols=False, auto_int_to_Integer=False): + """Construct new IPython session. """ + import IPython + + if version_tuple(IPython.__version__) >= version_tuple('0.11'): + if not shell: + # use an app to parse the command line, and init config + # IPython 1.0 deprecates the frontend module, so we import directly + # from the terminal module to prevent a deprecation message from being + # shown. + if version_tuple(IPython.__version__) >= version_tuple('1.0'): + from IPython.terminal import ipapp + else: + from IPython.frontend.terminal import ipapp + app = ipapp.TerminalIPythonApp() + + # don't draw IPython banner during initialization: + app.display_banner = False + app.initialize(argv) + + shell = app.shell + + if auto_symbols: + enable_automatic_symbols(shell) + if auto_int_to_Integer: + enable_automatic_int_sympification(shell) + + return shell + else: + from IPython.Shell import make_IPython + return make_IPython(argv) + + +def init_python_session(): + """Construct new Python session. """ + from code import InteractiveConsole + + class SymPyConsole(InteractiveConsole): + """An interactive console with readline support. """ + + def __init__(self): + ns_locals = {} + InteractiveConsole.__init__(self, locals=ns_locals) + try: + import rlcompleter + import readline + except ImportError: + pass + else: + import os + import atexit + + readline.set_completer(rlcompleter.Completer(ns_locals).complete) + readline.parse_and_bind('tab: complete') + + if hasattr(readline, 'read_history_file'): + history = os.path.expanduser('~/.sympy-history') + + try: + readline.read_history_file(history) + except OSError: + pass + + atexit.register(readline.write_history_file, history) + + return SymPyConsole() + + +def init_session(ipython=None, pretty_print=True, order=None, + use_unicode=None, use_latex=None, quiet=False, auto_symbols=False, + auto_int_to_Integer=False, str_printer=None, pretty_printer=None, + latex_printer=None, argv=[]): + """ + Initialize an embedded IPython or Python session. The IPython session is + initiated with the --pylab option, without the numpy imports, so that + matplotlib plotting can be interactive. + + Parameters + ========== + + pretty_print: boolean + If True, use pretty_print to stringify; + if False, use sstrrepr to stringify. + order: string or None + There are a few different settings for this parameter: + lex (default), which is lexographic order; + grlex, which is graded lexographic order; + grevlex, which is reversed graded lexographic order; + old, which is used for compatibility reasons and for long expressions; + None, which sets it to lex. + use_unicode: boolean or None + If True, use unicode characters; + if False, do not use unicode characters. + use_latex: boolean or None + If True, use latex rendering if IPython GUI's; + if False, do not use latex rendering. + quiet: boolean + If True, init_session will not print messages regarding its status; + if False, init_session will print messages regarding its status. + auto_symbols: boolean + If True, IPython will automatically create symbols for you. + If False, it will not. + The default is False. + auto_int_to_Integer: boolean + If True, IPython will automatically wrap int literals with Integer, so + that things like 1/2 give Rational(1, 2). + If False, it will not. + The default is False. + ipython: boolean or None + If True, printing will initialize for an IPython console; + if False, printing will initialize for a normal console; + The default is None, which automatically determines whether we are in + an ipython instance or not. + str_printer: function, optional, default=None + A custom string printer function. This should mimic + sympy.printing.sstrrepr(). + pretty_printer: function, optional, default=None + A custom pretty printer. This should mimic sympy.printing.pretty(). + latex_printer: function, optional, default=None + A custom LaTeX printer. This should mimic sympy.printing.latex() + This should mimic sympy.printing.latex(). + argv: list of arguments for IPython + See sympy.bin.isympy for options that can be used to initialize IPython. + + See Also + ======== + + sympy.interactive.printing.init_printing: for examples and the rest of the parameters. + + + Examples + ======== + + >>> from sympy import init_session, Symbol, sin, sqrt + >>> sin(x) #doctest: +SKIP + NameError: name 'x' is not defined + >>> init_session() #doctest: +SKIP + >>> sin(x) #doctest: +SKIP + sin(x) + >>> sqrt(5) #doctest: +SKIP + ___ + \\/ 5 + >>> init_session(pretty_print=False) #doctest: +SKIP + >>> sqrt(5) #doctest: +SKIP + sqrt(5) + >>> y + x + y**2 + x**2 #doctest: +SKIP + x**2 + x + y**2 + y + >>> init_session(order='grlex') #doctest: +SKIP + >>> y + x + y**2 + x**2 #doctest: +SKIP + x**2 + y**2 + x + y + >>> init_session(order='grevlex') #doctest: +SKIP + >>> y * x**2 + x * y**2 #doctest: +SKIP + x**2*y + x*y**2 + >>> init_session(order='old') #doctest: +SKIP + >>> x**2 + y**2 + x + y #doctest: +SKIP + x + y + x**2 + y**2 + >>> theta = Symbol('theta') #doctest: +SKIP + >>> theta #doctest: +SKIP + theta + >>> init_session(use_unicode=True) #doctest: +SKIP + >>> theta # doctest: +SKIP + \u03b8 + """ + import sys + + in_ipython = False + + if ipython is not False: + try: + import IPython + except ImportError: + if ipython is True: + raise RuntimeError("IPython is not available on this system") + ip = None + else: + try: + from IPython import get_ipython + ip = get_ipython() + except ImportError: + ip = None + in_ipython = bool(ip) + if ipython is None: + ipython = in_ipython + + if ipython is False: + ip = init_python_session() + mainloop = ip.interact + else: + ip = init_ipython_session(ip, argv=argv, auto_symbols=auto_symbols, + auto_int_to_Integer=auto_int_to_Integer) + + if version_tuple(IPython.__version__) >= version_tuple('0.11'): + # runsource is gone, use run_cell instead, which doesn't + # take a symbol arg. The second arg is `store_history`, + # and False means don't add the line to IPython's history. + ip.runsource = lambda src, symbol='exec': ip.run_cell(src, False) + + # Enable interactive plotting using pylab. + try: + ip.enable_pylab(import_all=False) + except Exception: + # Causes an import error if matplotlib is not installed. + # Causes other errors (depending on the backend) if there + # is no display, or if there is some problem in the + # backend, so we have a bare "except Exception" here + pass + if not in_ipython: + mainloop = ip.mainloop + + if auto_symbols and (not ipython or version_tuple(IPython.__version__) < version_tuple('0.11')): + raise RuntimeError("automatic construction of symbols is possible only in IPython 0.11 or above") + if auto_int_to_Integer and (not ipython or version_tuple(IPython.__version__) < version_tuple('0.11')): + raise RuntimeError("automatic int to Integer transformation is possible only in IPython 0.11 or above") + + _preexec_source = preexec_source + + ip.runsource(_preexec_source, symbol='exec') + init_printing(pretty_print=pretty_print, order=order, + use_unicode=use_unicode, use_latex=use_latex, ip=ip, + str_printer=str_printer, pretty_printer=pretty_printer, + latex_printer=latex_printer) + + message = _make_message(ipython, quiet, _preexec_source) + + if not in_ipython: + print(message) + mainloop() + sys.exit('Exiting ...') + else: + print(message) + import atexit + atexit.register(lambda: print("Exiting ...\n")) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/tests/test_interactive.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/tests/test_interactive.py new file mode 100644 index 0000000000000000000000000000000000000000..3e088c42fd872c13849e593b04734158f5d1e5bc --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/tests/test_interactive.py @@ -0,0 +1,10 @@ +from sympy.interactive.session import int_to_Integer + + +def test_int_to_Integer(): + assert int_to_Integer("1 + 2.2 + 0x3 + 40") == \ + 'Integer (1 )+2.2 +Integer (0x3 )+Integer (40 )' + assert int_to_Integer("0b101") == 'Integer (0b101 )' + assert int_to_Integer("ab1 + 1 + '1 + 2'") == "ab1 +Integer (1 )+'1 + 2'" + assert int_to_Integer("(2 + \n3)") == '(Integer (2 )+\nInteger (3 ))' + assert int_to_Integer("2 + 2.0 + 2j + 2e-10") == 'Integer (2 )+2.0 +2j +2e-10 ' diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/tests/test_ipython.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/tests/test_ipython.py new file mode 100644 index 0000000000000000000000000000000000000000..ac4734406d2f1197732a9dcbdd94b2b34e9fe170 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/tests/test_ipython.py @@ -0,0 +1,278 @@ +"""Tests of tools for setting up interactive IPython sessions. """ + +from sympy.interactive.session import (init_ipython_session, + enable_automatic_symbols, enable_automatic_int_sympification) + +from sympy.core import Symbol, Rational, Integer +from sympy.external import import_module +from sympy.testing.pytest import raises + +# TODO: The code below could be made more granular with something like: +# +# @requires('IPython', version=">=1.0") +# def test_automatic_symbols(ipython): + +ipython = import_module("IPython", min_module_version="1.0") + +if not ipython: + #bin/test will not execute any tests now + disabled = True + +# WARNING: These tests will modify the existing IPython environment. IPython +# uses a single instance for its interpreter, so there is no way to isolate +# the test from another IPython session. It also means that if this test is +# run twice in the same Python session it will fail. This isn't usually a +# problem because the test suite is run in a subprocess by default, but if the +# tests are run with subprocess=False it can pollute the current IPython +# session. See the discussion in issue #15149. + +def test_automatic_symbols(): + # NOTE: Because of the way the hook works, you have to use run_cell(code, + # True). This means that the code must have no Out, or it will be printed + # during the tests. + app = init_ipython_session() + app.run_cell("from sympy import *") + + enable_automatic_symbols(app) + + symbol = "verylongsymbolname" + assert symbol not in app.user_ns + app.run_cell("a = %s" % symbol, True) + assert symbol not in app.user_ns + app.run_cell("a = type(%s)" % symbol, True) + assert app.user_ns['a'] == Symbol + app.run_cell("%s = Symbol('%s')" % (symbol, symbol), True) + assert symbol in app.user_ns + + # Check that built-in names aren't overridden + app.run_cell("a = all == __builtin__.all", True) + assert "all" not in app.user_ns + assert app.user_ns['a'] is True + + # Check that SymPy names aren't overridden + app.run_cell("import sympy") + app.run_cell("a = factorial == sympy.factorial", True) + assert app.user_ns['a'] is True + + +def test_int_to_Integer(): + # XXX: Warning, don't test with == here. 0.5 == Rational(1, 2) is True! + app = init_ipython_session() + app.run_cell("from sympy import Integer") + app.run_cell("a = 1") + assert isinstance(app.user_ns['a'], int) + + enable_automatic_int_sympification(app) + app.run_cell("a = 1/2") + assert isinstance(app.user_ns['a'], Rational) + app.run_cell("a = 1") + assert isinstance(app.user_ns['a'], Integer) + app.run_cell("a = int(1)") + assert isinstance(app.user_ns['a'], int) + app.run_cell("a = (1/\n2)") + assert app.user_ns['a'] == Rational(1, 2) + # TODO: How can we test that the output of a SyntaxError is the original + # input, not the transformed input? + + +def test_ipythonprinting(): + # Initialize and setup IPython session + app = init_ipython_session() + app.run_cell("ip = get_ipython()") + app.run_cell("inst = ip.instance()") + app.run_cell("format = inst.display_formatter.format") + app.run_cell("from sympy import Symbol") + + # Printing without printing extension + app.run_cell("a = format(Symbol('pi'))") + app.run_cell("a2 = format(Symbol('pi')**2)") + # Deal with API change starting at IPython 1.0 + if int(ipython.__version__.split(".")[0]) < 1: + assert app.user_ns['a']['text/plain'] == "pi" + assert app.user_ns['a2']['text/plain'] == "pi**2" + else: + assert app.user_ns['a'][0]['text/plain'] == "pi" + assert app.user_ns['a2'][0]['text/plain'] == "pi**2" + + # Load printing extension + app.run_cell("from sympy import init_printing") + app.run_cell("init_printing()") + # Printing with printing extension + app.run_cell("a = format(Symbol('pi'))") + app.run_cell("a2 = format(Symbol('pi')**2)") + # Deal with API change starting at IPython 1.0 + if int(ipython.__version__.split(".")[0]) < 1: + assert app.user_ns['a']['text/plain'] in ('\N{GREEK SMALL LETTER PI}', 'pi') + assert app.user_ns['a2']['text/plain'] in (' 2\n\N{GREEK SMALL LETTER PI} ', ' 2\npi ') + else: + assert app.user_ns['a'][0]['text/plain'] in ('\N{GREEK SMALL LETTER PI}', 'pi') + assert app.user_ns['a2'][0]['text/plain'] in (' 2\n\N{GREEK SMALL LETTER PI} ', ' 2\npi ') + + +def test_print_builtin_option(): + # Initialize and setup IPython session + app = init_ipython_session() + app.run_cell("ip = get_ipython()") + app.run_cell("inst = ip.instance()") + app.run_cell("format = inst.display_formatter.format") + app.run_cell("from sympy import Symbol") + app.run_cell("from sympy import init_printing") + + app.run_cell("a = format({Symbol('pi'): 3.14, Symbol('n_i'): 3})") + # Deal with API change starting at IPython 1.0 + if int(ipython.__version__.split(".")[0]) < 1: + text = app.user_ns['a']['text/plain'] + raises(KeyError, lambda: app.user_ns['a']['text/latex']) + else: + text = app.user_ns['a'][0]['text/plain'] + raises(KeyError, lambda: app.user_ns['a'][0]['text/latex']) + # XXX: How can we make this ignore the terminal width? This test fails if + # the terminal is too narrow. + assert text in ("{pi: 3.14, n_i: 3}", + '{n\N{LATIN SUBSCRIPT SMALL LETTER I}: 3, \N{GREEK SMALL LETTER PI}: 3.14}', + "{n_i: 3, pi: 3.14}", + '{\N{GREEK SMALL LETTER PI}: 3.14, n\N{LATIN SUBSCRIPT SMALL LETTER I}: 3}') + + # If we enable the default printing, then the dictionary's should render + # as a LaTeX version of the whole dict: ${\pi: 3.14, n_i: 3}$ + app.run_cell("inst.display_formatter.formatters['text/latex'].enabled = True") + app.run_cell("init_printing(use_latex=True)") + app.run_cell("a = format({Symbol('pi'): 3.14, Symbol('n_i'): 3})") + # Deal with API change starting at IPython 1.0 + if int(ipython.__version__.split(".")[0]) < 1: + text = app.user_ns['a']['text/plain'] + latex = app.user_ns['a']['text/latex'] + else: + text = app.user_ns['a'][0]['text/plain'] + latex = app.user_ns['a'][0]['text/latex'] + assert text in ("{pi: 3.14, n_i: 3}", + '{n\N{LATIN SUBSCRIPT SMALL LETTER I}: 3, \N{GREEK SMALL LETTER PI}: 3.14}', + "{n_i: 3, pi: 3.14}", + '{\N{GREEK SMALL LETTER PI}: 3.14, n\N{LATIN SUBSCRIPT SMALL LETTER I}: 3}') + assert latex == r'$\displaystyle \left\{ n_{i} : 3, \ \pi : 3.14\right\}$' + + # Objects with an _latex overload should also be handled by our tuple + # printer. + app.run_cell("""\ + class WithOverload: + def _latex(self, printer): + return r"\\LaTeX" + """) + app.run_cell("a = format((WithOverload(),))") + # Deal with API change starting at IPython 1.0 + if int(ipython.__version__.split(".")[0]) < 1: + latex = app.user_ns['a']['text/latex'] + else: + latex = app.user_ns['a'][0]['text/latex'] + assert latex == r'$\displaystyle \left( \LaTeX,\right)$' + + app.run_cell("inst.display_formatter.formatters['text/latex'].enabled = True") + app.run_cell("init_printing(use_latex=True, print_builtin=False)") + app.run_cell("a = format({Symbol('pi'): 3.14, Symbol('n_i'): 3})") + # Deal with API change starting at IPython 1.0 + if int(ipython.__version__.split(".")[0]) < 1: + text = app.user_ns['a']['text/plain'] + raises(KeyError, lambda: app.user_ns['a']['text/latex']) + else: + text = app.user_ns['a'][0]['text/plain'] + raises(KeyError, lambda: app.user_ns['a'][0]['text/latex']) + # Note : In Python 3 we have one text type: str which holds Unicode data + # and two byte types bytes and bytearray. + # Python 3.3.3 + IPython 0.13.2 gives: '{n_i: 3, pi: 3.14}' + # Python 3.3.3 + IPython 1.1.0 gives: '{n_i: 3, pi: 3.14}' + assert text in ("{pi: 3.14, n_i: 3}", "{n_i: 3, pi: 3.14}") + + +def test_builtin_containers(): + # Initialize and setup IPython session + app = init_ipython_session() + app.run_cell("ip = get_ipython()") + app.run_cell("inst = ip.instance()") + app.run_cell("format = inst.display_formatter.format") + app.run_cell("inst.display_formatter.formatters['text/latex'].enabled = True") + app.run_cell("from sympy import init_printing, Matrix") + app.run_cell('init_printing(use_latex=True, use_unicode=False)') + + # Make sure containers that shouldn't pretty print don't. + app.run_cell('a = format((True, False))') + app.run_cell('import sys') + app.run_cell('b = format(sys.flags)') + app.run_cell('c = format((Matrix([1, 2]),))') + # Deal with API change starting at IPython 1.0 + if int(ipython.__version__.split(".")[0]) < 1: + assert app.user_ns['a']['text/plain'] == '(True, False)' + assert 'text/latex' not in app.user_ns['a'] + assert app.user_ns['b']['text/plain'][:10] == 'sys.flags(' + assert 'text/latex' not in app.user_ns['b'] + assert app.user_ns['c']['text/plain'] == \ +"""\ + [1] \n\ +([ ],) + [2] \ +""" + assert app.user_ns['c']['text/latex'] == '$\\displaystyle \\left( \\left[\\begin{matrix}1\\\\2\\end{matrix}\\right],\\right)$' + else: + assert app.user_ns['a'][0]['text/plain'] == '(True, False)' + assert 'text/latex' not in app.user_ns['a'][0] + assert app.user_ns['b'][0]['text/plain'][:10] == 'sys.flags(' + assert 'text/latex' not in app.user_ns['b'][0] + assert app.user_ns['c'][0]['text/plain'] == \ +"""\ + [1] \n\ +([ ],) + [2] \ +""" + assert app.user_ns['c'][0]['text/latex'] == '$\\displaystyle \\left( \\left[\\begin{matrix}1\\\\2\\end{matrix}\\right],\\right)$' + +def test_matplotlib_bad_latex(): + # Initialize and setup IPython session + app = init_ipython_session() + app.run_cell("import IPython") + app.run_cell("ip = get_ipython()") + app.run_cell("inst = ip.instance()") + app.run_cell("format = inst.display_formatter.format") + app.run_cell("from sympy import init_printing, Matrix") + app.run_cell("init_printing(use_latex='matplotlib')") + + # The png formatter is not enabled by default in this context + app.run_cell("inst.display_formatter.formatters['image/png'].enabled = True") + + # Make sure no warnings are raised by IPython + app.run_cell("import warnings") + # IPython.core.formatters.FormatterWarning was introduced in IPython 2.0 + if int(ipython.__version__.split(".")[0]) < 2: + app.run_cell("warnings.simplefilter('error')") + else: + app.run_cell("warnings.simplefilter('error', IPython.core.formatters.FormatterWarning)") + + # This should not raise an exception + app.run_cell("a = format(Matrix([1, 2, 3]))") + + # issue 9799 + app.run_cell("from sympy import Piecewise, Symbol, Eq") + app.run_cell("x = Symbol('x'); pw = format(Piecewise((1, Eq(x, 0)), (0, True)))") + + +def test_override_repr_latex(): + # Initialize and setup IPython session + app = init_ipython_session() + app.run_cell("import IPython") + app.run_cell("ip = get_ipython()") + app.run_cell("inst = ip.instance()") + app.run_cell("format = inst.display_formatter.format") + app.run_cell("inst.display_formatter.formatters['text/latex'].enabled = True") + app.run_cell("from sympy import init_printing") + app.run_cell("from sympy import Symbol") + app.run_cell("init_printing(use_latex=True)") + app.run_cell("""\ + class SymbolWithOverload(Symbol): + def _repr_latex_(self): + return r"Hello " + super()._repr_latex_() + " world" + """) + app.run_cell("a = format(SymbolWithOverload('s'))") + + if int(ipython.__version__.split(".")[0]) < 1: + latex = app.user_ns['a']['text/latex'] + else: + latex = app.user_ns['a'][0]['text/latex'] + assert latex == r'Hello $\displaystyle s$ world' diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/traversal.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/traversal.py new file mode 100644 index 0000000000000000000000000000000000000000..1315ec4ef7868b666bb6b978b3d8b20442d100b0 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/interactive/traversal.py @@ -0,0 +1,95 @@ +from sympy.core.basic import Basic +from sympy.printing import pprint + +import random + +def interactive_traversal(expr): + """Traverse a tree asking a user which branch to choose. """ + + RED, BRED = '\033[0;31m', '\033[1;31m' + GREEN, BGREEN = '\033[0;32m', '\033[1;32m' + YELLOW, BYELLOW = '\033[0;33m', '\033[1;33m' # noqa + BLUE, BBLUE = '\033[0;34m', '\033[1;34m' # noqa + MAGENTA, BMAGENTA = '\033[0;35m', '\033[1;35m'# noqa + CYAN, BCYAN = '\033[0;36m', '\033[1;36m' # noqa + END = '\033[0m' + + def cprint(*args): + print("".join(map(str, args)) + END) + + def _interactive_traversal(expr, stage): + if stage > 0: + print() + + cprint("Current expression (stage ", BYELLOW, stage, END, "):") + print(BCYAN) + pprint(expr) + print(END) + + if isinstance(expr, Basic): + if expr.is_Add: + args = expr.as_ordered_terms() + elif expr.is_Mul: + args = expr.as_ordered_factors() + else: + args = expr.args + elif hasattr(expr, "__iter__"): + args = list(expr) + else: + return expr + + n_args = len(args) + + if not n_args: + return expr + + for i, arg in enumerate(args): + cprint(GREEN, "[", BGREEN, i, GREEN, "] ", BLUE, type(arg), END) + pprint(arg) + print() + + if n_args == 1: + choices = '0' + else: + choices = '0-%d' % (n_args - 1) + + try: + choice = input("Your choice [%s,f,l,r,d,?]: " % choices) + except EOFError: + result = expr + print() + else: + if choice == '?': + cprint(RED, "%s - select subexpression with the given index" % + choices) + cprint(RED, "f - select the first subexpression") + cprint(RED, "l - select the last subexpression") + cprint(RED, "r - select a random subexpression") + cprint(RED, "d - done\n") + + result = _interactive_traversal(expr, stage) + elif choice in ('d', ''): + result = expr + elif choice == 'f': + result = _interactive_traversal(args[0], stage + 1) + elif choice == 'l': + result = _interactive_traversal(args[-1], stage + 1) + elif choice == 'r': + result = _interactive_traversal(random.choice(args), stage + 1) + else: + try: + choice = int(choice) + except ValueError: + cprint(BRED, + "Choice must be a number in %s range\n" % choices) + result = _interactive_traversal(expr, stage) + else: + if choice < 0 or choice >= n_args: + cprint(BRED, "Choice must be in %s range\n" % choices) + result = _interactive_traversal(expr, stage) + else: + result = _interactive_traversal(args[choice], stage + 1) + + return result + + return _interactive_traversal(expr, 0) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..d023d86f2c6f0c64d7ac460c50eedc355e78b21f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/__init__.py @@ -0,0 +1,3 @@ +from sympy.liealgebras.cartan_type import CartanType + +__all__ = ['CartanType'] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/cartan_matrix.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/cartan_matrix.py new file mode 100644 index 0000000000000000000000000000000000000000..2d29b37bc9a1a26790ee88b5902951afe4fc4560 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/cartan_matrix.py @@ -0,0 +1,25 @@ +from .cartan_type import CartanType + +def CartanMatrix(ct): + """Access the Cartan matrix of a specific Lie algebra + + Examples + ======== + + >>> from sympy.liealgebras.cartan_matrix import CartanMatrix + >>> CartanMatrix("A2") + Matrix([ + [ 2, -1], + [-1, 2]]) + + >>> CartanMatrix(['C', 3]) + Matrix([ + [ 2, -1, 0], + [-1, 2, -1], + [ 0, -2, 2]]) + + This method works by returning the Cartan matrix + which corresponds to Cartan type t. + """ + + return CartanType(ct).cartan_matrix() diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/cartan_type.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/cartan_type.py new file mode 100644 index 0000000000000000000000000000000000000000..16bb152469238ea912a30c2d0f8210d6f729bdb1 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/cartan_type.py @@ -0,0 +1,73 @@ +from sympy.core import Atom, Basic + + +class CartanType_generator(): + """ + Constructor for actually creating things + """ + def __call__(self, *args): + c = args[0] + if isinstance(c, list): + letter, n = c[0], int(c[1]) + elif isinstance(c, str): + letter, n = c[0], int(c[1:]) + else: + raise TypeError("Argument must be a string (e.g. 'A3') or a list (e.g. ['A', 3])") + + if n < 0: + raise ValueError("Lie algebra rank cannot be negative") + if letter == "A": + from . import type_a + return type_a.TypeA(n) + if letter == "B": + from . import type_b + return type_b.TypeB(n) + + if letter == "C": + from . import type_c + return type_c.TypeC(n) + + if letter == "D": + from . import type_d + return type_d.TypeD(n) + + if letter == "E": + if n >= 6 and n <= 8: + from . import type_e + return type_e.TypeE(n) + + if letter == "F": + if n == 4: + from . import type_f + return type_f.TypeF(n) + + if letter == "G": + if n == 2: + from . import type_g + return type_g.TypeG(n) + +CartanType = CartanType_generator() + + +class Standard_Cartan(Atom): + """ + Concrete base class for Cartan types such as A4, etc + """ + + def __new__(cls, series, n): + obj = Basic.__new__(cls) + obj.n = n + obj.series = series + return obj + + def rank(self): + """ + Returns the rank of the Lie algebra + """ + return self.n + + def series(self): + """ + Returns the type of the Lie algebra + """ + return self.series diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/dynkin_diagram.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/dynkin_diagram.py new file mode 100644 index 0000000000000000000000000000000000000000..cc9e2dac4d54490b803eeaf9637cb9b66b01f058 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/dynkin_diagram.py @@ -0,0 +1,24 @@ +from .cartan_type import CartanType + + +def DynkinDiagram(t): + """Display the Dynkin diagram of a given Lie algebra + + Works by generating the CartanType for the input, t, and then returning the + Dynkin diagram method from the individual classes. + + Examples + ======== + + >>> from sympy.liealgebras.dynkin_diagram import DynkinDiagram + >>> print(DynkinDiagram("A3")) + 0---0---0 + 1 2 3 + + >>> print(DynkinDiagram("B4")) + 0---0---0=>=0 + 1 2 3 4 + + """ + + return CartanType(t).dynkin_diagram() diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/root_system.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/root_system.py new file mode 100644 index 0000000000000000000000000000000000000000..36eb24605e78bbdc669736910d89be5606df1389 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/root_system.py @@ -0,0 +1,196 @@ +from .cartan_type import CartanType +from sympy.core.basic import Atom + +class RootSystem(Atom): + """Represent the root system of a simple Lie algebra + + Every simple Lie algebra has a unique root system. To find the root + system, we first consider the Cartan subalgebra of g, which is the maximal + abelian subalgebra, and consider the adjoint action of g on this + subalgebra. There is a root system associated with this action. Now, a + root system over a vector space V is a set of finite vectors Phi (called + roots), which satisfy: + + 1. The roots span V + 2. The only scalar multiples of x in Phi are x and -x + 3. For every x in Phi, the set Phi is closed under reflection + through the hyperplane perpendicular to x. + 4. If x and y are roots in Phi, then the projection of y onto + the line through x is a half-integral multiple of x. + + Now, there is a subset of Phi, which we will call Delta, such that: + 1. Delta is a basis of V + 2. Each root x in Phi can be written x = sum k_y y for y in Delta + + The elements of Delta are called the simple roots. + Therefore, we see that the simple roots span the root space of a given + simple Lie algebra. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Root_system + .. [2] Lie Algebras and Representation Theory - Humphreys + + """ + + def __new__(cls, cartantype): + """Create a new RootSystem object + + This method assigns an attribute called cartan_type to each instance of + a RootSystem object. When an instance of RootSystem is called, it + needs an argument, which should be an instance of a simple Lie algebra. + We then take the CartanType of this argument and set it as the + cartan_type attribute of the RootSystem instance. + + """ + obj = Atom.__new__(cls) + obj.cartan_type = CartanType(cartantype) + return obj + + def simple_roots(self): + """Generate the simple roots of the Lie algebra + + The rank of the Lie algebra determines the number of simple roots that + it has. This method obtains the rank of the Lie algebra, and then uses + the simple_root method from the Lie algebra classes to generate all the + simple roots. + + Examples + ======== + + >>> from sympy.liealgebras.root_system import RootSystem + >>> c = RootSystem("A3") + >>> roots = c.simple_roots() + >>> roots + {1: [1, -1, 0, 0], 2: [0, 1, -1, 0], 3: [0, 0, 1, -1]} + + """ + n = self.cartan_type.rank() + roots = {i: self.cartan_type.simple_root(i) for i in range(1, n+1)} + return roots + + + def all_roots(self): + """Generate all the roots of a given root system + + The result is a dictionary where the keys are integer numbers. It + generates the roots by getting the dictionary of all positive roots + from the bases classes, and then taking each root, and multiplying it + by -1 and adding it to the dictionary. In this way all the negative + roots are generated. + + """ + alpha = self.cartan_type.positive_roots() + keys = list(alpha.keys()) + k = max(keys) + for val in keys: + k += 1 + root = alpha[val] + newroot = [-x for x in root] + alpha[k] = newroot + return alpha + + def root_space(self): + """Return the span of the simple roots + + The root space is the vector space spanned by the simple roots, i.e. it + is a vector space with a distinguished basis, the simple roots. This + method returns a string that represents the root space as the span of + the simple roots, alpha[1],...., alpha[n]. + + Examples + ======== + + >>> from sympy.liealgebras.root_system import RootSystem + >>> c = RootSystem("A3") + >>> c.root_space() + 'alpha[1] + alpha[2] + alpha[3]' + + """ + n = self.cartan_type.rank() + rs = " + ".join("alpha["+str(i) +"]" for i in range(1, n+1)) + return rs + + def add_simple_roots(self, root1, root2): + """Add two simple roots together + + The function takes as input two integers, root1 and root2. It then + uses these integers as keys in the dictionary of simple roots, and gets + the corresponding simple roots, and then adds them together. + + Examples + ======== + + >>> from sympy.liealgebras.root_system import RootSystem + >>> c = RootSystem("A3") + >>> newroot = c.add_simple_roots(1, 2) + >>> newroot + [1, 0, -1, 0] + + """ + + alpha = self.simple_roots() + if root1 > len(alpha) or root2 > len(alpha): + raise ValueError("You've used a root that doesn't exist!") + a1 = alpha[root1] + a2 = alpha[root2] + newroot = [_a1 + _a2 for _a1, _a2 in zip(a1, a2)] + return newroot + + def add_as_roots(self, root1, root2): + """Add two roots together if and only if their sum is also a root + + It takes as input two vectors which should be roots. It then computes + their sum and checks if it is in the list of all possible roots. If it + is, it returns the sum. Otherwise it returns a string saying that the + sum is not a root. + + Examples + ======== + + >>> from sympy.liealgebras.root_system import RootSystem + >>> c = RootSystem("A3") + >>> c.add_as_roots([1, 0, -1, 0], [0, 0, 1, -1]) + [1, 0, 0, -1] + >>> c.add_as_roots([1, -1, 0, 0], [0, 0, -1, 1]) + 'The sum of these two roots is not a root' + + """ + alpha = self.all_roots() + newroot = [r1 + r2 for r1, r2 in zip(root1, root2)] + if newroot in alpha.values(): + return newroot + else: + return "The sum of these two roots is not a root" + + + def cartan_matrix(self): + """Cartan matrix of Lie algebra associated with this root system + + Examples + ======== + + >>> from sympy.liealgebras.root_system import RootSystem + >>> c = RootSystem("A3") + >>> c.cartan_matrix() + Matrix([ + [ 2, -1, 0], + [-1, 2, -1], + [ 0, -1, 2]]) + """ + return self.cartan_type.cartan_matrix() + + def dynkin_diagram(self): + """Dynkin diagram of the Lie algebra associated with this root system + + Examples + ======== + + >>> from sympy.liealgebras.root_system import RootSystem + >>> c = RootSystem("A3") + >>> print(c.dynkin_diagram()) + 0---0---0 + 1 2 3 + """ + return self.cartan_type.dynkin_diagram() diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_cartan_matrix.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_cartan_matrix.py new file mode 100644 index 0000000000000000000000000000000000000000..98b1793dee63e0e87c610768554a8388dfd641a1 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_cartan_matrix.py @@ -0,0 +1,10 @@ +from sympy.liealgebras.cartan_matrix import CartanMatrix +from sympy.matrices import Matrix + +def test_CartanMatrix(): + c = CartanMatrix("A3") + m = Matrix(3, 3, [2, -1, 0, -1, 2, -1, 0, -1, 2]) + assert c == m + a = CartanMatrix(["G",2]) + mt = Matrix(2, 2, [2, -1, -3, 2]) + assert a == mt diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_cartan_type.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_cartan_type.py new file mode 100644 index 0000000000000000000000000000000000000000..257eeca41d0f5f2eb240cc270f76d452848ed405 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_cartan_type.py @@ -0,0 +1,12 @@ +from sympy.liealgebras.cartan_type import CartanType, Standard_Cartan + +def test_Standard_Cartan(): + c = CartanType("A4") + assert c.rank() == 4 + assert c.series == "A" + m = Standard_Cartan("A", 2) + assert m.rank() == 2 + assert m.series == "A" + b = CartanType("B12") + assert b.rank() == 12 + assert b.series == "B" diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_dynkin_diagram.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_dynkin_diagram.py new file mode 100644 index 0000000000000000000000000000000000000000..ad2ee4c162945c437ecf83d75c7fef9455c9464a --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_dynkin_diagram.py @@ -0,0 +1,9 @@ +from sympy.liealgebras.dynkin_diagram import DynkinDiagram + +def test_DynkinDiagram(): + c = DynkinDiagram("A3") + diag = "0---0---0\n1 2 3" + assert c == diag + ct = DynkinDiagram(["B", 3]) + diag2 = "0---0=>=0\n1 2 3" + assert ct == diag2 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_root_system.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_root_system.py new file mode 100644 index 0000000000000000000000000000000000000000..42110da5a1c59a7e6b2e537ee13746bfce361579 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_root_system.py @@ -0,0 +1,18 @@ +from sympy.liealgebras.root_system import RootSystem +from sympy.liealgebras.type_a import TypeA +from sympy.matrices import Matrix + +def test_root_system(): + c = RootSystem("A3") + assert c.cartan_type == TypeA(3) + assert c.simple_roots() == {1: [1, -1, 0, 0], 2: [0, 1, -1, 0], 3: [0, 0, 1, -1]} + assert c.root_space() == "alpha[1] + alpha[2] + alpha[3]" + assert c.cartan_matrix() == Matrix([[ 2, -1, 0], [-1, 2, -1], [ 0, -1, 2]]) + assert c.dynkin_diagram() == "0---0---0\n1 2 3" + assert c.add_simple_roots(1, 2) == [1, 0, -1, 0] + assert c.all_roots() == {1: [1, -1, 0, 0], 2: [1, 0, -1, 0], + 3: [1, 0, 0, -1], 4: [0, 1, -1, 0], 5: [0, 1, 0, -1], + 6: [0, 0, 1, -1], 7: [-1, 1, 0, 0], 8: [-1, 0, 1, 0], + 9: [-1, 0, 0, 1], 10: [0, -1, 1, 0], + 11: [0, -1, 0, 1], 12: [0, 0, -1, 1]} + assert c.add_as_roots([1, 0, -1, 0], [0, 0, 1, -1]) == [1, 0, 0, -1] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_A.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_A.py new file mode 100644 index 0000000000000000000000000000000000000000..85d6f451ee167cf6db17ab20e59efab86ac0b691 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_A.py @@ -0,0 +1,17 @@ +from sympy.liealgebras.cartan_type import CartanType +from sympy.matrices import Matrix + +def test_type_A(): + c = CartanType("A3") + m = Matrix(3, 3, [2, -1, 0, -1, 2, -1, 0, -1, 2]) + assert m == c.cartan_matrix() + assert c.basis() == 8 + assert c.roots() == 12 + assert c.dimension() == 4 + assert c.simple_root(1) == [1, -1, 0, 0] + assert c.highest_root() == [1, 0, 0, -1] + assert c.lie_algebra() == "su(4)" + diag = "0---0---0\n1 2 3" + assert c.dynkin_diagram() == diag + assert c.positive_roots() == {1: [1, -1, 0, 0], 2: [1, 0, -1, 0], + 3: [1, 0, 0, -1], 4: [0, 1, -1, 0], 5: [0, 1, 0, -1], 6: [0, 0, 1, -1]} diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_B.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_B.py new file mode 100644 index 0000000000000000000000000000000000000000..8f2a9011f96bc647e48d39e16cf10703a99d86b3 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_B.py @@ -0,0 +1,17 @@ +from sympy.liealgebras.cartan_type import CartanType +from sympy.matrices import Matrix + +def test_type_B(): + c = CartanType("B3") + m = Matrix(3, 3, [2, -1, 0, -1, 2, -2, 0, -1, 2]) + assert m == c.cartan_matrix() + assert c.dimension() == 3 + assert c.roots() == 18 + assert c.simple_root(3) == [0, 0, 1] + assert c.basis() == 3 + assert c.lie_algebra() == "so(6)" + diag = "0---0=>=0\n1 2 3" + assert c.dynkin_diagram() == diag + assert c.positive_roots() == {1: [1, -1, 0], 2: [1, 1, 0], 3: [1, 0, -1], + 4: [1, 0, 1], 5: [0, 1, -1], 6: [0, 1, 1], 7: [1, 0, 0], + 8: [0, 1, 0], 9: [0, 0, 1]} diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_C.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_C.py new file mode 100644 index 0000000000000000000000000000000000000000..8154c201e6c50adb7c74458b240ed98b9a0dd123 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_C.py @@ -0,0 +1,22 @@ +from sympy.liealgebras.cartan_type import CartanType +from sympy.matrices import Matrix + +def test_type_C(): + c = CartanType("C4") + m = Matrix(4, 4, [2, -1, 0, 0, -1, 2, -1, 0, 0, -1, 2, -1, 0, 0, -2, 2]) + assert c.cartan_matrix() == m + assert c.dimension() == 4 + assert c.simple_root(4) == [0, 0, 0, 2] + assert c.roots() == 32 + assert c.basis() == 36 + assert c.lie_algebra() == "sp(8)" + t = CartanType(['C', 3]) + assert t.dimension() == 3 + diag = "0---0---0=<=0\n1 2 3 4" + assert c.dynkin_diagram() == diag + assert c.positive_roots() == {1: [1, -1, 0, 0], 2: [1, 1, 0, 0], + 3: [1, 0, -1, 0], 4: [1, 0, 1, 0], 5: [1, 0, 0, -1], + 6: [1, 0, 0, 1], 7: [0, 1, -1, 0], 8: [0, 1, 1, 0], + 9: [0, 1, 0, -1], 10: [0, 1, 0, 1], 11: [0, 0, 1, -1], + 12: [0, 0, 1, 1], 13: [2, 0, 0, 0], 14: [0, 2, 0, 0], 15: [0, 0, 2, 0], + 16: [0, 0, 0, 2]} diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_D.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_D.py new file mode 100644 index 0000000000000000000000000000000000000000..ddf6a34cb5be475cc30042e95bf8eae2376a2223 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_D.py @@ -0,0 +1,19 @@ +from sympy.liealgebras.cartan_type import CartanType +from sympy.matrices import Matrix + + + +def test_type_D(): + c = CartanType("D4") + m = Matrix(4, 4, [2, -1, 0, 0, -1, 2, -1, -1, 0, -1, 2, 0, 0, -1, 0, 2]) + assert c.cartan_matrix() == m + assert c.basis() == 6 + assert c.lie_algebra() == "so(8)" + assert c.roots() == 24 + assert c.simple_root(3) == [0, 0, 1, -1] + diag = " 3\n 0\n |\n |\n0---0---0\n1 2 4" + assert diag == c.dynkin_diagram() + assert c.positive_roots() == {1: [1, -1, 0, 0], 2: [1, 1, 0, 0], + 3: [1, 0, -1, 0], 4: [1, 0, 1, 0], 5: [1, 0, 0, -1], 6: [1, 0, 0, 1], + 7: [0, 1, -1, 0], 8: [0, 1, 1, 0], 9: [0, 1, 0, -1], 10: [0, 1, 0, 1], + 11: [0, 0, 1, -1], 12: [0, 0, 1, 1]} diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_E.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_E.py new file mode 100644 index 0000000000000000000000000000000000000000..bdb08342f41ede3390f34e9b297864eda16bedc7 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_E.py @@ -0,0 +1,22 @@ +from sympy.liealgebras.cartan_type import CartanType +from sympy.matrices import Matrix +from sympy.core.backend import Rational + +def test_type_E(): + c = CartanType("E6") + m = Matrix(6, 6, [2, 0, -1, 0, 0, 0, 0, 2, 0, -1, 0, 0, + -1, 0, 2, -1, 0, 0, 0, -1, -1, 2, -1, 0, 0, 0, 0, + -1, 2, -1, 0, 0, 0, 0, -1, 2]) + assert c.cartan_matrix() == m + assert c.dimension() == 8 + assert c.simple_root(6) == [0, 0, 0, -1, 1, 0, 0, 0] + assert c.roots() == 72 + assert c.basis() == 78 + diag = " "*8 + "2\n" + " "*8 + "0\n" + " "*8 + "|\n" + " "*8 + "|\n" + diag += "---".join("0" for i in range(1, 6))+"\n" + diag += "1 " + " ".join(str(i) for i in range(3, 7)) + assert c.dynkin_diagram() == diag + posroots = c.positive_roots() + assert posroots[8] == [1, 0, 0, 0, 1, 0, 0, 0] + assert posroots[21] == [Rational(1,2),Rational(1,2),Rational(1,2),Rational(1,2), + Rational(1,2),Rational(-1,2),Rational(-1,2),Rational(1,2)] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_F.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_F.py new file mode 100644 index 0000000000000000000000000000000000000000..fbb58223d0b5886e6044108c9c5cc3bbf371dd14 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_F.py @@ -0,0 +1,24 @@ +from sympy.liealgebras.cartan_type import CartanType +from sympy.matrices import Matrix +from sympy.core.backend import S + +def test_type_F(): + c = CartanType("F4") + m = Matrix(4, 4, [2, -1, 0, 0, -1, 2, -2, 0, 0, -1, 2, -1, 0, 0, -1, 2]) + assert c.cartan_matrix() == m + assert c.dimension() == 4 + assert c.simple_root(1) == [1, -1, 0, 0] + assert c.simple_root(2) == [0, 1, -1, 0] + assert c.simple_root(3) == [0, 0, 0, 1] + assert c.simple_root(4) == [-S.Half, -S.Half, -S.Half, -S.Half] + assert c.roots() == 48 + assert c.basis() == 52 + diag = "0---0=>=0---0\n" + " ".join(str(i) for i in range(1, 5)) + assert c.dynkin_diagram() == diag + assert c.positive_roots() == {1: [1, -1, 0, 0], 2: [1, 1, 0, 0], 3: [1, 0, -1, 0], + 4: [1, 0, 1, 0], 5: [1, 0, 0, -1], 6: [1, 0, 0, 1], 7: [0, 1, -1, 0], + 8: [0, 1, 1, 0], 9: [0, 1, 0, -1], 10: [0, 1, 0, 1], 11: [0, 0, 1, -1], + 12: [0, 0, 1, 1], 13: [1, 0, 0, 0], 14: [0, 1, 0, 0], 15: [0, 0, 1, 0], + 16: [0, 0, 0, 1], 17: [S.Half, S.Half, S.Half, S.Half], 18: [S.Half, -S.Half, S.Half, S.Half], + 19: [S.Half, S.Half, -S.Half, S.Half], 20: [S.Half, S.Half, S.Half, -S.Half], 21: [S.Half, S.Half, -S.Half, -S.Half], + 22: [S.Half, -S.Half, S.Half, -S.Half], 23: [S.Half, -S.Half, -S.Half, S.Half], 24: [S.Half, -S.Half, -S.Half, -S.Half]} diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_G.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_G.py new file mode 100644 index 0000000000000000000000000000000000000000..c427eeb85bad8fc77d17a1563a7b796d4e0f217f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_type_G.py @@ -0,0 +1,16 @@ +# coding=utf-8 +from sympy.liealgebras.cartan_type import CartanType +from sympy.matrices import Matrix + +def test_type_G(): + c = CartanType("G2") + m = Matrix(2, 2, [2, -1, -3, 2]) + assert c.cartan_matrix() == m + assert c.simple_root(2) == [1, -2, 1] + assert c.basis() == 14 + assert c.roots() == 12 + assert c.dimension() == 3 + diag = "0≡<≡0\n1 2" + assert diag == c.dynkin_diagram() + assert c.positive_roots() == {1: [0, 1, -1], 2: [1, -2, 1], 3: [1, -1, 0], + 4: [1, 0, 1], 5: [1, 1, -2], 6: [2, -1, -1]} diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_weyl_group.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_weyl_group.py new file mode 100644 index 0000000000000000000000000000000000000000..e4e57246fdcb5a431d8bbd65f1f60e0254a9cdf0 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/tests/test_weyl_group.py @@ -0,0 +1,35 @@ +from sympy.liealgebras.weyl_group import WeylGroup +from sympy.matrices import Matrix + +def test_weyl_group(): + c = WeylGroup("A3") + assert c.matrix_form('r1*r2') == Matrix([[0, 0, 1, 0], [1, 0, 0, 0], + [0, 1, 0, 0], [0, 0, 0, 1]]) + assert c.generators() == ['r1', 'r2', 'r3'] + assert c.group_order() == 24.0 + assert c.group_name() == "S4: the symmetric group acting on 4 elements." + assert c.coxeter_diagram() == "0---0---0\n1 2 3" + assert c.element_order('r1*r2*r3') == 4 + assert c.element_order('r1*r3*r2*r3') == 3 + d = WeylGroup("B5") + assert d.group_order() == 3840 + assert d.element_order('r1*r2*r4*r5') == 12 + assert d.matrix_form('r2*r3') == Matrix([[0, 0, 1, 0, 0], [1, 0, 0, 0, 0], + [0, 1, 0, 0, 0], [0, 0, 0, 1, 0], [0, 0, 0, 0, 1]]) + assert d.element_order('r1*r2*r1*r3*r5') == 6 + e = WeylGroup("D5") + assert e.element_order('r2*r3*r5') == 4 + assert e.matrix_form('r2*r3*r5') == Matrix([[1, 0, 0, 0, 0], [0, 0, 0, 0, -1], + [0, 1, 0, 0, 0], [0, 0, 1, 0, 0], [0, 0, 0, -1, 0]]) + f = WeylGroup("G2") + assert f.element_order('r1*r2*r1*r2') == 3 + assert f.element_order('r2*r1*r1*r2') == 1 + + assert f.matrix_form('r1*r2*r1*r2') == Matrix([[0, 1, 0], [0, 0, 1], [1, 0, 0]]) + g = WeylGroup("F4") + assert g.matrix_form('r2*r3') == Matrix([[1, 0, 0, 0], [0, 1, 0, 0], + [0, 0, 0, -1], [0, 0, 1, 0]]) + + assert g.element_order('r2*r3') == 4 + h = WeylGroup("E6") + assert h.group_order() == 51840 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_a.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_a.py new file mode 100644 index 0000000000000000000000000000000000000000..96dc615366ae20d668d651620ac088f15751c50e --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_a.py @@ -0,0 +1,164 @@ +from sympy.liealgebras.cartan_type import Standard_Cartan +from sympy.core.backend import eye + + +class TypeA(Standard_Cartan): + """ + This class contains the information about + the A series of simple Lie algebras. + ==== + """ + + def __new__(cls, n): + if n < 1: + raise ValueError("n cannot be less than 1") + return Standard_Cartan.__new__(cls, "A", n) + + + def dimension(self): + """Dimension of the vector space V underlying the Lie algebra + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("A4") + >>> c.dimension() + 5 + """ + return self.n+1 + + + def basic_root(self, i, j): + """ + This is a method just to generate roots + with a 1 iin the ith position and a -1 + in the jth position. + + """ + + n = self.n + root = [0]*(n+1) + root[i] = 1 + root[j] = -1 + return root + + def simple_root(self, i): + """ + Every lie algebra has a unique root system. + Given a root system Q, there is a subset of the + roots such that an element of Q is called a + simple root if it cannot be written as the sum + of two elements in Q. If we let D denote the + set of simple roots, then it is clear that every + element of Q can be written as a linear combination + of elements of D with all coefficients non-negative. + + In A_n the ith simple root is the root which has a 1 + in the ith position, a -1 in the (i+1)th position, + and zeroes elsewhere. + + This method returns the ith simple root for the A series. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("A4") + >>> c.simple_root(1) + [1, -1, 0, 0, 0] + + """ + + return self.basic_root(i-1, i) + + def positive_roots(self): + """ + This method generates all the positive roots of + A_n. This is half of all of the roots of A_n; + by multiplying all the positive roots by -1 we + get the negative roots. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("A3") + >>> c.positive_roots() + {1: [1, -1, 0, 0], 2: [1, 0, -1, 0], 3: [1, 0, 0, -1], 4: [0, 1, -1, 0], + 5: [0, 1, 0, -1], 6: [0, 0, 1, -1]} + """ + + n = self.n + posroots = {} + k = 0 + for i in range(0, n): + for j in range(i+1, n+1): + k += 1 + posroots[k] = self.basic_root(i, j) + return posroots + + def highest_root(self): + """ + Returns the highest weight root for A_n + """ + + return self.basic_root(0, self.n) + + def roots(self): + """ + Returns the total number of roots for A_n + """ + n = self.n + return n*(n+1) + + def cartan_matrix(self): + """ + Returns the Cartan matrix for A_n. + The Cartan matrix matrix for a Lie algebra is + generated by assigning an ordering to the simple + roots, (alpha[1], ...., alpha[l]). Then the ijth + entry of the Cartan matrix is (). + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType('A4') + >>> c.cartan_matrix() + Matrix([ + [ 2, -1, 0, 0], + [-1, 2, -1, 0], + [ 0, -1, 2, -1], + [ 0, 0, -1, 2]]) + + """ + + n = self.n + m = 2 * eye(n) + for i in range(1, n - 1): + m[i, i+1] = -1 + m[i, i-1] = -1 + m[0,1] = -1 + m[n-1, n-2] = -1 + return m + + def basis(self): + """ + Returns the number of independent generators of A_n + """ + n = self.n + return n**2 - 1 + + def lie_algebra(self): + """ + Returns the Lie algebra associated with A_n + """ + n = self.n + return "su(" + str(n + 1) + ")" + + def dynkin_diagram(self): + n = self.n + diag = "---".join("0" for i in range(1, n+1)) + "\n" + diag += " ".join(str(i) for i in range(1, n+1)) + return diag diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_b.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_b.py new file mode 100644 index 0000000000000000000000000000000000000000..c6ee85502261f4702769067c64021521a2bc1725 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_b.py @@ -0,0 +1,170 @@ +from .cartan_type import Standard_Cartan +from sympy.core.backend import eye + +class TypeB(Standard_Cartan): + + def __new__(cls, n): + if n < 2: + raise ValueError("n cannot be less than 2") + return Standard_Cartan.__new__(cls, "B", n) + + def dimension(self): + """Dimension of the vector space V underlying the Lie algebra + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("B3") + >>> c.dimension() + 3 + """ + + return self.n + + def basic_root(self, i, j): + """ + This is a method just to generate roots + with a 1 iin the ith position and a -1 + in the jth position. + + """ + root = [0]*self.n + root[i] = 1 + root[j] = -1 + return root + + def simple_root(self, i): + """ + Every lie algebra has a unique root system. + Given a root system Q, there is a subset of the + roots such that an element of Q is called a + simple root if it cannot be written as the sum + of two elements in Q. If we let D denote the + set of simple roots, then it is clear that every + element of Q can be written as a linear combination + of elements of D with all coefficients non-negative. + + In B_n the first n-1 simple roots are the same as the + roots in A_(n-1) (a 1 in the ith position, a -1 in + the (i+1)th position, and zeroes elsewhere). The n-th + simple root is the root with a 1 in the nth position + and zeroes elsewhere. + + This method returns the ith simple root for the B series. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("B3") + >>> c.simple_root(2) + [0, 1, -1] + + """ + n = self.n + if i < n: + return self.basic_root(i-1, i) + else: + root = [0]*self.n + root[n-1] = 1 + return root + + def positive_roots(self): + """ + This method generates all the positive roots of + A_n. This is half of all of the roots of B_n; + by multiplying all the positive roots by -1 we + get the negative roots. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("A3") + >>> c.positive_roots() + {1: [1, -1, 0, 0], 2: [1, 0, -1, 0], 3: [1, 0, 0, -1], 4: [0, 1, -1, 0], + 5: [0, 1, 0, -1], 6: [0, 0, 1, -1]} + """ + + n = self.n + posroots = {} + k = 0 + for i in range(0, n-1): + for j in range(i+1, n): + k += 1 + posroots[k] = self.basic_root(i, j) + k += 1 + root = self.basic_root(i, j) + root[j] = 1 + posroots[k] = root + + for i in range(0, n): + k += 1 + root = [0]*n + root[i] = 1 + posroots[k] = root + + return posroots + + def roots(self): + """ + Returns the total number of roots for B_n" + """ + + n = self.n + return 2*(n**2) + + def cartan_matrix(self): + """ + Returns the Cartan matrix for B_n. + The Cartan matrix matrix for a Lie algebra is + generated by assigning an ordering to the simple + roots, (alpha[1], ...., alpha[l]). Then the ijth + entry of the Cartan matrix is (). + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType('B4') + >>> c.cartan_matrix() + Matrix([ + [ 2, -1, 0, 0], + [-1, 2, -1, 0], + [ 0, -1, 2, -2], + [ 0, 0, -1, 2]]) + + """ + + n = self.n + m = 2* eye(n) + for i in range(1, n - 1): + m[i, i+1] = -1 + m[i, i-1] = -1 + m[0, 1] = -1 + m[n-2, n-1] = -2 + m[n-1, n-2] = -1 + return m + + def basis(self): + """ + Returns the number of independent generators of B_n + """ + + n = self.n + return (n**2 - n)/2 + + def lie_algebra(self): + """ + Returns the Lie algebra associated with B_n + """ + + n = self.n + return "so(" + str(2*n) + ")" + + def dynkin_diagram(self): + n = self.n + diag = "---".join("0" for i in range(1, n)) + "=>=0\n" + diag += " ".join(str(i) for i in range(1, n+1)) + return diag diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_c.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_c.py new file mode 100644 index 0000000000000000000000000000000000000000..615bb900b5ba9613fd02e43f476d34eef0d5d35c --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_c.py @@ -0,0 +1,169 @@ +from .cartan_type import Standard_Cartan +from sympy.core.backend import eye + +class TypeC(Standard_Cartan): + + def __new__(cls, n): + if n < 3: + raise ValueError("n cannot be less than 3") + return Standard_Cartan.__new__(cls, "C", n) + + + def dimension(self): + """Dimension of the vector space V underlying the Lie algebra + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("C3") + >>> c.dimension() + 3 + """ + n = self.n + return n + + def basic_root(self, i, j): + """Generate roots with 1 in ith position and a -1 in jth position + """ + n = self.n + root = [0]*n + root[i] = 1 + root[j] = -1 + return root + + def simple_root(self, i): + """The ith simple root for the C series + + Every lie algebra has a unique root system. + Given a root system Q, there is a subset of the + roots such that an element of Q is called a + simple root if it cannot be written as the sum + of two elements in Q. If we let D denote the + set of simple roots, then it is clear that every + element of Q can be written as a linear combination + of elements of D with all coefficients non-negative. + + In C_n, the first n-1 simple roots are the same as + the roots in A_(n-1) (a 1 in the ith position, a -1 + in the (i+1)th position, and zeroes elsewhere). The + nth simple root is the root in which there is a 2 in + the nth position and zeroes elsewhere. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("C3") + >>> c.simple_root(2) + [0, 1, -1] + + """ + + n = self.n + if i < n: + return self.basic_root(i-1,i) + else: + root = [0]*self.n + root[n-1] = 2 + return root + + + def positive_roots(self): + """Generates all the positive roots of A_n + + This is half of all of the roots of C_n; by multiplying all the + positive roots by -1 we get the negative roots. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("A3") + >>> c.positive_roots() + {1: [1, -1, 0, 0], 2: [1, 0, -1, 0], 3: [1, 0, 0, -1], 4: [0, 1, -1, 0], + 5: [0, 1, 0, -1], 6: [0, 0, 1, -1]} + + """ + + n = self.n + posroots = {} + k = 0 + for i in range(0, n-1): + for j in range(i+1, n): + k += 1 + posroots[k] = self.basic_root(i, j) + k += 1 + root = self.basic_root(i, j) + root[j] = 1 + posroots[k] = root + + for i in range(0, n): + k += 1 + root = [0]*n + root[i] = 2 + posroots[k] = root + + return posroots + + def roots(self): + """ + Returns the total number of roots for C_n" + """ + + n = self.n + return 2*(n**2) + + def cartan_matrix(self): + """The Cartan matrix for C_n + + The Cartan matrix matrix for a Lie algebra is + generated by assigning an ordering to the simple + roots, (alpha[1], ...., alpha[l]). Then the ijth + entry of the Cartan matrix is (). + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType('C4') + >>> c.cartan_matrix() + Matrix([ + [ 2, -1, 0, 0], + [-1, 2, -1, 0], + [ 0, -1, 2, -1], + [ 0, 0, -2, 2]]) + + """ + + n = self.n + m = 2 * eye(n) + for i in range(1, n - 1): + m[i, i+1] = -1 + m[i, i-1] = -1 + m[0,1] = -1 + m[n-1, n-2] = -2 + return m + + + def basis(self): + """ + Returns the number of independent generators of C_n + """ + + n = self.n + return n*(2*n + 1) + + def lie_algebra(self): + """ + Returns the Lie algebra associated with C_n" + """ + + n = self.n + return "sp(" + str(2*n) + ")" + + def dynkin_diagram(self): + n = self.n + diag = "---".join("0" for i in range(1, n)) + "=<=0\n" + diag += " ".join(str(i) for i in range(1, n+1)) + return diag diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_d.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_d.py new file mode 100644 index 0000000000000000000000000000000000000000..9450d76e906c79e23db0ce223ed0de03d71c1199 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_d.py @@ -0,0 +1,173 @@ +from .cartan_type import Standard_Cartan +from sympy.core.backend import eye + +class TypeD(Standard_Cartan): + + def __new__(cls, n): + if n < 3: + raise ValueError("n cannot be less than 3") + return Standard_Cartan.__new__(cls, "D", n) + + + def dimension(self): + """Dmension of the vector space V underlying the Lie algebra + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("D4") + >>> c.dimension() + 4 + """ + + return self.n + + def basic_root(self, i, j): + """ + This is a method just to generate roots + with a 1 iin the ith position and a -1 + in the jth position. + + """ + + n = self.n + root = [0]*n + root[i] = 1 + root[j] = -1 + return root + + def simple_root(self, i): + """ + Every lie algebra has a unique root system. + Given a root system Q, there is a subset of the + roots such that an element of Q is called a + simple root if it cannot be written as the sum + of two elements in Q. If we let D denote the + set of simple roots, then it is clear that every + element of Q can be written as a linear combination + of elements of D with all coefficients non-negative. + + In D_n, the first n-1 simple roots are the same as + the roots in A_(n-1) (a 1 in the ith position, a -1 + in the (i+1)th position, and zeroes elsewhere). + The nth simple root is the root in which there 1s in + the nth and (n-1)th positions, and zeroes elsewhere. + + This method returns the ith simple root for the D series. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("D4") + >>> c.simple_root(2) + [0, 1, -1, 0] + + """ + + n = self.n + if i < n: + return self.basic_root(i-1, i) + else: + root = [0]*n + root[n-2] = 1 + root[n-1] = 1 + return root + + + def positive_roots(self): + """ + This method generates all the positive roots of + A_n. This is half of all of the roots of D_n + by multiplying all the positive roots by -1 we + get the negative roots. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("A3") + >>> c.positive_roots() + {1: [1, -1, 0, 0], 2: [1, 0, -1, 0], 3: [1, 0, 0, -1], 4: [0, 1, -1, 0], + 5: [0, 1, 0, -1], 6: [0, 0, 1, -1]} + """ + + n = self.n + posroots = {} + k = 0 + for i in range(0, n-1): + for j in range(i+1, n): + k += 1 + posroots[k] = self.basic_root(i, j) + k += 1 + root = self.basic_root(i, j) + root[j] = 1 + posroots[k] = root + return posroots + + def roots(self): + """ + Returns the total number of roots for D_n" + """ + + n = self.n + return 2*n*(n-1) + + def cartan_matrix(self): + """ + Returns the Cartan matrix for D_n. + The Cartan matrix matrix for a Lie algebra is + generated by assigning an ordering to the simple + roots, (alpha[1], ...., alpha[l]). Then the ijth + entry of the Cartan matrix is (). + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType('D4') + >>> c.cartan_matrix() + Matrix([ + [ 2, -1, 0, 0], + [-1, 2, -1, -1], + [ 0, -1, 2, 0], + [ 0, -1, 0, 2]]) + + """ + + n = self.n + m = 2*eye(n) + for i in range(1, n - 2): + m[i,i+1] = -1 + m[i,i-1] = -1 + m[n-2, n-3] = -1 + m[n-3, n-1] = -1 + m[n-1, n-3] = -1 + m[0, 1] = -1 + return m + + def basis(self): + """ + Returns the number of independent generators of D_n + """ + n = self.n + return n*(n-1)/2 + + def lie_algebra(self): + """ + Returns the Lie algebra associated with D_n" + """ + + n = self.n + return "so(" + str(2*n) + ")" + + def dynkin_diagram(self): + n = self.n + diag = " "*4*(n-3) + str(n-1) + "\n" + diag += " "*4*(n-3) + "0\n" + diag += " "*4*(n-3) +"|\n" + diag += " "*4*(n-3) + "|\n" + diag += "---".join("0" for i in range(1,n)) + "\n" + diag += " ".join(str(i) for i in range(1, n-1)) + " "+str(n) + return diag diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_e.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_e.py new file mode 100644 index 0000000000000000000000000000000000000000..3db9a820d31bff31acc58ba1592a1b10f8be53db --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_e.py @@ -0,0 +1,275 @@ +import itertools + +from .cartan_type import Standard_Cartan +from sympy.core.backend import eye, Rational +from sympy.core.singleton import S + +class TypeE(Standard_Cartan): + + def __new__(cls, n): + if n < 6 or n > 8: + raise ValueError("Invalid value of n") + return Standard_Cartan.__new__(cls, "E", n) + + def dimension(self): + """Dimension of the vector space V underlying the Lie algebra + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("E6") + >>> c.dimension() + 8 + """ + + return 8 + + def basic_root(self, i, j): + """ + This is a method just to generate roots + with a -1 in the ith position and a 1 + in the jth position. + + """ + + root = [0]*8 + root[i] = -1 + root[j] = 1 + return root + + def simple_root(self, i): + """ + Every Lie algebra has a unique root system. + Given a root system Q, there is a subset of the + roots such that an element of Q is called a + simple root if it cannot be written as the sum + of two elements in Q. If we let D denote the + set of simple roots, then it is clear that every + element of Q can be written as a linear combination + of elements of D with all coefficients non-negative. + + This method returns the ith simple root for E_n. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("E6") + >>> c.simple_root(2) + [1, 1, 0, 0, 0, 0, 0, 0] + """ + n = self.n + if i == 1: + root = [-0.5]*8 + root[0] = 0.5 + root[7] = 0.5 + return root + elif i == 2: + root = [0]*8 + root[1] = 1 + root[0] = 1 + return root + else: + if i in (7, 8) and n == 6: + raise ValueError("E6 only has six simple roots!") + if i == 8 and n == 7: + raise ValueError("E7 only has seven simple roots!") + + return self.basic_root(i - 3, i - 2) + + def positive_roots(self): + """ + This method generates all the positive roots of + A_n. This is half of all of the roots of E_n; + by multiplying all the positive roots by -1 we + get the negative roots. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("A3") + >>> c.positive_roots() + {1: [1, -1, 0, 0], 2: [1, 0, -1, 0], 3: [1, 0, 0, -1], 4: [0, 1, -1, 0], + 5: [0, 1, 0, -1], 6: [0, 0, 1, -1]} + """ + n = self.n + neghalf = Rational(-1, 2) + poshalf = S.Half + if n == 6: + posroots = {} + k = 0 + for i in range(n-1): + for j in range(i+1, n-1): + k += 1 + root = self.basic_root(i, j) + posroots[k] = root + k += 1 + root = self.basic_root(i, j) + root[i] = 1 + posroots[k] = root + + root = [poshalf, poshalf, poshalf, poshalf, poshalf, + neghalf, neghalf, poshalf] + for a, b, c, d, e in itertools.product( + range(2), range(2), range(2), range(2), range(2)): + if (a + b + c + d + e)%2 == 0: + k += 1 + if a == 1: + root[0] = neghalf + if b == 1: + root[1] = neghalf + if c == 1: + root[2] = neghalf + if d == 1: + root[3] = neghalf + if e == 1: + root[4] = neghalf + posroots[k] = root[:] + return posroots + if n == 7: + posroots = {} + k = 0 + for i in range(n-1): + for j in range(i+1, n-1): + k += 1 + root = self.basic_root(i, j) + posroots[k] = root + k += 1 + root = self.basic_root(i, j) + root[i] = 1 + posroots[k] = root + + k += 1 + posroots[k] = [0, 0, 0, 0, 0, 1, 1, 0] + root = [poshalf, poshalf, poshalf, poshalf, poshalf, + neghalf, neghalf, poshalf] + for a, b, c, d, e, f in itertools.product( + range(2), range(2), range(2), range(2), range(2), range(2)): + if (a + b + c + d + e + f)%2 == 0: + k += 1 + if a == 1: + root[0] = neghalf + if b == 1: + root[1] = neghalf + if c == 1: + root[2] = neghalf + if d == 1: + root[3] = neghalf + if e == 1: + root[4] = neghalf + if f == 1: + root[5] = poshalf + posroots[k] = root[:] + return posroots + if n == 8: + posroots = {} + k = 0 + for i in range(n): + for j in range(i+1, n): + k += 1 + root = self.basic_root(i, j) + posroots[k] = root + k += 1 + root = self.basic_root(i, j) + root[i] = 1 + posroots[k] = root + + root = [poshalf, poshalf, poshalf, poshalf, poshalf, + neghalf, neghalf, poshalf] + for a, b, c, d, e, f, g in itertools.product( + range(2), range(2), range(2), range(2), range(2), + range(2), range(2)): + if (a + b + c + d + e + f + g)%2 == 0: + k += 1 + if a == 1: + root[0] = neghalf + if b == 1: + root[1] = neghalf + if c == 1: + root[2] = neghalf + if d == 1: + root[3] = neghalf + if e == 1: + root[4] = neghalf + if f == 1: + root[5] = poshalf + if g == 1: + root[6] = poshalf + posroots[k] = root[:] + return posroots + + + + def roots(self): + """ + Returns the total number of roots of E_n + """ + + n = self.n + if n == 6: + return 72 + if n == 7: + return 126 + if n == 8: + return 240 + + + def cartan_matrix(self): + """ + Returns the Cartan matrix for G_2 + The Cartan matrix matrix for a Lie algebra is + generated by assigning an ordering to the simple + roots, (alpha[1], ...., alpha[l]). Then the ijth + entry of the Cartan matrix is (). + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType('A4') + >>> c.cartan_matrix() + Matrix([ + [ 2, -1, 0, 0], + [-1, 2, -1, 0], + [ 0, -1, 2, -1], + [ 0, 0, -1, 2]]) + + + """ + + n = self.n + m = 2*eye(n) + for i in range(3, n - 1): + m[i, i+1] = -1 + m[i, i-1] = -1 + m[0, 2] = m[2, 0] = -1 + m[1, 3] = m[3, 1] = -1 + m[2, 3] = -1 + m[n-1, n-2] = -1 + return m + + + def basis(self): + """ + Returns the number of independent generators of E_n + """ + + n = self.n + if n == 6: + return 78 + if n == 7: + return 133 + if n == 8: + return 248 + + def dynkin_diagram(self): + n = self.n + diag = " "*8 + str(2) + "\n" + diag += " "*8 + "0\n" + diag += " "*8 + "|\n" + diag += " "*8 + "|\n" + diag += "---".join("0" for i in range(1, n)) + "\n" + diag += "1 " + " ".join(str(i) for i in range(3, n+1)) + return diag diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_f.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_f.py new file mode 100644 index 0000000000000000000000000000000000000000..f04da557870f2cd21818cf69c454ef598e2ab65a --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_f.py @@ -0,0 +1,162 @@ +from .cartan_type import Standard_Cartan +from sympy.core.backend import Matrix, Rational + + +class TypeF(Standard_Cartan): + + def __new__(cls, n): + if n != 4: + raise ValueError("n should be 4") + return Standard_Cartan.__new__(cls, "F", 4) + + def dimension(self): + """Dimension of the vector space V underlying the Lie algebra + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("F4") + >>> c.dimension() + 4 + """ + + return 4 + + + def basic_root(self, i, j): + """Generate roots with 1 in ith position and -1 in jth position + + """ + + n = self.n + root = [0]*n + root[i] = 1 + root[j] = -1 + return root + + def simple_root(self, i): + """The ith simple root of F_4 + + Every lie algebra has a unique root system. + Given a root system Q, there is a subset of the + roots such that an element of Q is called a + simple root if it cannot be written as the sum + of two elements in Q. If we let D denote the + set of simple roots, then it is clear that every + element of Q can be written as a linear combination + of elements of D with all coefficients non-negative. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("F4") + >>> c.simple_root(3) + [0, 0, 0, 1] + + """ + + if i < 3: + return self.basic_root(i-1, i) + if i == 3: + root = [0]*4 + root[3] = 1 + return root + if i == 4: + root = [Rational(-1, 2)]*4 + return root + + def positive_roots(self): + """Generate all the positive roots of A_n + + This is half of all of the roots of F_4; by multiplying all the + positive roots by -1 we get the negative roots. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("A3") + >>> c.positive_roots() + {1: [1, -1, 0, 0], 2: [1, 0, -1, 0], 3: [1, 0, 0, -1], 4: [0, 1, -1, 0], + 5: [0, 1, 0, -1], 6: [0, 0, 1, -1]} + + """ + + n = self.n + posroots = {} + k = 0 + for i in range(0, n-1): + for j in range(i+1, n): + k += 1 + posroots[k] = self.basic_root(i, j) + k += 1 + root = self.basic_root(i, j) + root[j] = 1 + posroots[k] = root + + for i in range(0, n): + k += 1 + root = [0]*n + root[i] = 1 + posroots[k] = root + + k += 1 + root = [Rational(1, 2)]*n + posroots[k] = root + for i in range(1, 4): + k += 1 + root = [Rational(1, 2)]*n + root[i] = Rational(-1, 2) + posroots[k] = root + + posroots[k+1] = [Rational(1, 2), Rational(1, 2), Rational(-1, 2), Rational(-1, 2)] + posroots[k+2] = [Rational(1, 2), Rational(-1, 2), Rational(1, 2), Rational(-1, 2)] + posroots[k+3] = [Rational(1, 2), Rational(-1, 2), Rational(-1, 2), Rational(1, 2)] + posroots[k+4] = [Rational(1, 2), Rational(-1, 2), Rational(-1, 2), Rational(-1, 2)] + + return posroots + + + def roots(self): + """ + Returns the total number of roots for F_4 + """ + return 48 + + def cartan_matrix(self): + """The Cartan matrix for F_4 + + The Cartan matrix matrix for a Lie algebra is + generated by assigning an ordering to the simple + roots, (alpha[1], ...., alpha[l]). Then the ijth + entry of the Cartan matrix is (). + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType('A4') + >>> c.cartan_matrix() + Matrix([ + [ 2, -1, 0, 0], + [-1, 2, -1, 0], + [ 0, -1, 2, -1], + [ 0, 0, -1, 2]]) + """ + + m = Matrix( 4, 4, [2, -1, 0, 0, -1, 2, -2, 0, 0, + -1, 2, -1, 0, 0, -1, 2]) + return m + + def basis(self): + """ + Returns the number of independent generators of F_4 + """ + return 52 + + def dynkin_diagram(self): + diag = "0---0=>=0---0\n" + diag += " ".join(str(i) for i in range(1, 5)) + return diag diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_g.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_g.py new file mode 100644 index 0000000000000000000000000000000000000000..014409cf5ed966b53c596b14e0073e89ceee05b6 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/type_g.py @@ -0,0 +1,111 @@ +# -*- coding: utf-8 -*- + +from .cartan_type import Standard_Cartan +from sympy.core.backend import Matrix + +class TypeG(Standard_Cartan): + + def __new__(cls, n): + if n != 2: + raise ValueError("n should be 2") + return Standard_Cartan.__new__(cls, "G", 2) + + + def dimension(self): + """Dimension of the vector space V underlying the Lie algebra + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("G2") + >>> c.dimension() + 3 + """ + return 3 + + def simple_root(self, i): + """The ith simple root of G_2 + + Every lie algebra has a unique root system. + Given a root system Q, there is a subset of the + roots such that an element of Q is called a + simple root if it cannot be written as the sum + of two elements in Q. If we let D denote the + set of simple roots, then it is clear that every + element of Q can be written as a linear combination + of elements of D with all coefficients non-negative. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("G2") + >>> c.simple_root(1) + [0, 1, -1] + + """ + if i == 1: + return [0, 1, -1] + else: + return [1, -2, 1] + + def positive_roots(self): + """Generate all the positive roots of A_n + + This is half of all of the roots of A_n; by multiplying all the + positive roots by -1 we get the negative roots. + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("A3") + >>> c.positive_roots() + {1: [1, -1, 0, 0], 2: [1, 0, -1, 0], 3: [1, 0, 0, -1], 4: [0, 1, -1, 0], + 5: [0, 1, 0, -1], 6: [0, 0, 1, -1]} + + """ + + roots = {1: [0, 1, -1], 2: [1, -2, 1], 3: [1, -1, 0], 4: [1, 0, 1], + 5: [1, 1, -2], 6: [2, -1, -1]} + return roots + + def roots(self): + """ + Returns the total number of roots of G_2" + """ + return 12 + + def cartan_matrix(self): + """The Cartan matrix for G_2 + + The Cartan matrix matrix for a Lie algebra is + generated by assigning an ordering to the simple + roots, (alpha[1], ...., alpha[l]). Then the ijth + entry of the Cartan matrix is (). + + Examples + ======== + + >>> from sympy.liealgebras.cartan_type import CartanType + >>> c = CartanType("G2") + >>> c.cartan_matrix() + Matrix([ + [ 2, -1], + [-3, 2]]) + + """ + + m = Matrix( 2, 2, [2, -1, -3, 2]) + return m + + def basis(self): + """ + Returns the number of independent generators of G_2 + """ + return 14 + + def dynkin_diagram(self): + diag = "0≡<≡0\n1 2" + return diag diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/weyl_group.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/weyl_group.py new file mode 100644 index 0000000000000000000000000000000000000000..15ff70b6f1fc4649268a38ee13e1f717a1c9f5fa --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/liealgebras/weyl_group.py @@ -0,0 +1,403 @@ +# -*- coding: utf-8 -*- + +from .cartan_type import CartanType +from mpmath import fac +from sympy.core.backend import Matrix, eye, Rational, igcd +from sympy.core.basic import Atom + +class WeylGroup(Atom): + + """ + For each semisimple Lie group, we have a Weyl group. It is a subgroup of + the isometry group of the root system. Specifically, it's the subgroup + that is generated by reflections through the hyperplanes orthogonal to + the roots. Therefore, Weyl groups are reflection groups, and so a Weyl + group is a finite Coxeter group. + + """ + + def __new__(cls, cartantype): + obj = Atom.__new__(cls) + obj.cartan_type = CartanType(cartantype) + return obj + + def generators(self): + """ + This method creates the generating reflections of the Weyl group for + a given Lie algebra. For a Lie algebra of rank n, there are n + different generating reflections. This function returns them as + a list. + + Examples + ======== + + >>> from sympy.liealgebras.weyl_group import WeylGroup + >>> c = WeylGroup("F4") + >>> c.generators() + ['r1', 'r2', 'r3', 'r4'] + """ + n = self.cartan_type.rank() + generators = [] + for i in range(1, n+1): + reflection = "r"+str(i) + generators.append(reflection) + return generators + + def group_order(self): + """ + This method returns the order of the Weyl group. + For types A, B, C, D, and E the order depends on + the rank of the Lie algebra. For types F and G, + the order is fixed. + + Examples + ======== + + >>> from sympy.liealgebras.weyl_group import WeylGroup + >>> c = WeylGroup("D4") + >>> c.group_order() + 192.0 + """ + n = self.cartan_type.rank() + if self.cartan_type.series == "A": + return fac(n+1) + + if self.cartan_type.series in ("B", "C"): + return fac(n)*(2**n) + + if self.cartan_type.series == "D": + return fac(n)*(2**(n-1)) + + if self.cartan_type.series == "E": + if n == 6: + return 51840 + if n == 7: + return 2903040 + if n == 8: + return 696729600 + if self.cartan_type.series == "F": + return 1152 + + if self.cartan_type.series == "G": + return 12 + + def group_name(self): + """ + This method returns some general information about the Weyl group for + a given Lie algebra. It returns the name of the group and the elements + it acts on, if relevant. + """ + n = self.cartan_type.rank() + if self.cartan_type.series == "A": + return "S"+str(n+1) + ": the symmetric group acting on " + str(n+1) + " elements." + + if self.cartan_type.series in ("B", "C"): + return "The hyperoctahedral group acting on " + str(2*n) + " elements." + + if self.cartan_type.series == "D": + return "The symmetry group of the " + str(n) + "-dimensional demihypercube." + + if self.cartan_type.series == "E": + if n == 6: + return "The symmetry group of the 6-polytope." + + if n == 7: + return "The symmetry group of the 7-polytope." + + if n == 8: + return "The symmetry group of the 8-polytope." + + if self.cartan_type.series == "F": + return "The symmetry group of the 24-cell, or icositetrachoron." + + if self.cartan_type.series == "G": + return "D6, the dihedral group of order 12, and symmetry group of the hexagon." + + def element_order(self, weylelt): + """ + This method returns the order of a given Weyl group element, which should + be specified by the user in the form of products of the generating + reflections, i.e. of the form r1*r2 etc. + + For types A-F, this method current works by taking the matrix form of + the specified element, and then finding what power of the matrix is the + identity. It then returns this power. + + Examples + ======== + + >>> from sympy.liealgebras.weyl_group import WeylGroup + >>> b = WeylGroup("B4") + >>> b.element_order('r1*r4*r2') + 4 + """ + n = self.cartan_type.rank() + if self.cartan_type.series == "A": + a = self.matrix_form(weylelt) + order = 1 + while a != eye(n+1): + a *= self.matrix_form(weylelt) + order += 1 + return order + + if self.cartan_type.series == "D": + a = self.matrix_form(weylelt) + order = 1 + while a != eye(n): + a *= self.matrix_form(weylelt) + order += 1 + return order + + if self.cartan_type.series == "E": + a = self.matrix_form(weylelt) + order = 1 + while a != eye(8): + a *= self.matrix_form(weylelt) + order += 1 + return order + + if self.cartan_type.series == "G": + elts = list(weylelt) + reflections = elts[1::3] + m = self.delete_doubles(reflections) + while self.delete_doubles(m) != m: + m = self.delete_doubles(m) + reflections = m + if len(reflections) % 2 == 1: + return 2 + + elif len(reflections) == 0: + return 1 + + else: + if len(reflections) == 1: + return 2 + else: + m = len(reflections) // 2 + lcm = (6 * m)/ igcd(m, 6) + order = lcm / m + return order + + + if self.cartan_type.series == 'F': + a = self.matrix_form(weylelt) + order = 1 + while a != eye(4): + a *= self.matrix_form(weylelt) + order += 1 + return order + + + if self.cartan_type.series in ("B", "C"): + a = self.matrix_form(weylelt) + order = 1 + while a != eye(n): + a *= self.matrix_form(weylelt) + order += 1 + return order + + def delete_doubles(self, reflections): + """ + This is a helper method for determining the order of an element in the + Weyl group of G2. It takes a Weyl element and if repeated simple reflections + in it, it deletes them. + """ + counter = 0 + copy = list(reflections) + for elt in copy: + if counter < len(copy)-1: + if copy[counter + 1] == elt: + del copy[counter] + del copy[counter] + counter += 1 + + + return copy + + + def matrix_form(self, weylelt): + """ + This method takes input from the user in the form of products of the + generating reflections, and returns the matrix corresponding to the + element of the Weyl group. Since each element of the Weyl group is + a reflection of some type, there is a corresponding matrix representation. + This method uses the standard representation for all the generating + reflections. + + Examples + ======== + + >>> from sympy.liealgebras.weyl_group import WeylGroup + >>> f = WeylGroup("F4") + >>> f.matrix_form('r2*r3') + Matrix([ + [1, 0, 0, 0], + [0, 1, 0, 0], + [0, 0, 0, -1], + [0, 0, 1, 0]]) + + """ + elts = list(weylelt) + reflections = elts[1::3] + n = self.cartan_type.rank() + if self.cartan_type.series == 'A': + matrixform = eye(n+1) + for elt in reflections: + a = int(elt) + mat = eye(n+1) + mat[a-1, a-1] = 0 + mat[a-1, a] = 1 + mat[a, a-1] = 1 + mat[a, a] = 0 + matrixform *= mat + return matrixform + + if self.cartan_type.series == 'D': + matrixform = eye(n) + for elt in reflections: + a = int(elt) + mat = eye(n) + if a < n: + mat[a-1, a-1] = 0 + mat[a-1, a] = 1 + mat[a, a-1] = 1 + mat[a, a] = 0 + matrixform *= mat + else: + mat[n-2, n-1] = -1 + mat[n-2, n-2] = 0 + mat[n-1, n-2] = -1 + mat[n-1, n-1] = 0 + matrixform *= mat + return matrixform + + if self.cartan_type.series == 'G': + matrixform = eye(3) + for elt in reflections: + a = int(elt) + if a == 1: + gen1 = Matrix([[1, 0, 0], [0, 0, 1], [0, 1, 0]]) + matrixform *= gen1 + else: + gen2 = Matrix([[Rational(2, 3), Rational(2, 3), Rational(-1, 3)], + [Rational(2, 3), Rational(-1, 3), Rational(2, 3)], + [Rational(-1, 3), Rational(2, 3), Rational(2, 3)]]) + matrixform *= gen2 + return matrixform + + if self.cartan_type.series == 'F': + matrixform = eye(4) + for elt in reflections: + a = int(elt) + if a == 1: + mat = Matrix([[1, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 0], [0, 0, 0, 1]]) + matrixform *= mat + elif a == 2: + mat = Matrix([[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 0, 1], [0, 0, 1, 0]]) + matrixform *= mat + elif a == 3: + mat = Matrix([[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, -1]]) + matrixform *= mat + else: + + mat = Matrix([[Rational(1, 2), Rational(1, 2), Rational(1, 2), Rational(1, 2)], + [Rational(1, 2), Rational(1, 2), Rational(-1, 2), Rational(-1, 2)], + [Rational(1, 2), Rational(-1, 2), Rational(1, 2), Rational(-1, 2)], + [Rational(1, 2), Rational(-1, 2), Rational(-1, 2), Rational(1, 2)]]) + matrixform *= mat + return matrixform + + if self.cartan_type.series == 'E': + matrixform = eye(8) + for elt in reflections: + a = int(elt) + if a == 1: + mat = Matrix([[Rational(3, 4), Rational(1, 4), Rational(1, 4), Rational(1, 4), + Rational(1, 4), Rational(1, 4), Rational(1, 4), Rational(-1, 4)], + [Rational(1, 4), Rational(3, 4), Rational(-1, 4), Rational(-1, 4), + Rational(-1, 4), Rational(-1, 4), Rational(1, 4), Rational(-1, 4)], + [Rational(1, 4), Rational(-1, 4), Rational(3, 4), Rational(-1, 4), + Rational(-1, 4), Rational(-1, 4), Rational(-1, 4), Rational(1, 4)], + [Rational(1, 4), Rational(-1, 4), Rational(-1, 4), Rational(3, 4), + Rational(-1, 4), Rational(-1, 4), Rational(-1, 4), Rational(1, 4)], + [Rational(1, 4), Rational(-1, 4), Rational(-1, 4), Rational(-1, 4), + Rational(3, 4), Rational(-1, 4), Rational(-1, 4), Rational(1, 4)], + [Rational(1, 4), Rational(-1, 4), Rational(-1, 4), Rational(-1, 4), + Rational(-1, 4), Rational(3, 4), Rational(-1, 4), Rational(1, 4)], + [Rational(1, 4), Rational(-1, 4), Rational(-1, 4), Rational(-1, 4), + Rational(-1, 4), Rational(-1, 4), Rational(-3, 4), Rational(1, 4)], + [Rational(1, 4), Rational(-1, 4), Rational(-1, 4), Rational(-1, 4), + Rational(-1, 4), Rational(-1, 4), Rational(-1, 4), Rational(3, 4)]]) + matrixform *= mat + elif a == 2: + mat = eye(8) + mat[0, 0] = 0 + mat[0, 1] = -1 + mat[1, 0] = -1 + mat[1, 1] = 0 + matrixform *= mat + else: + mat = eye(8) + mat[a-3, a-3] = 0 + mat[a-3, a-2] = 1 + mat[a-2, a-3] = 1 + mat[a-2, a-2] = 0 + matrixform *= mat + return matrixform + + + if self.cartan_type.series in ("B", "C"): + matrixform = eye(n) + for elt in reflections: + a = int(elt) + mat = eye(n) + if a == 1: + mat[0, 0] = -1 + matrixform *= mat + else: + mat[a - 2, a - 2] = 0 + mat[a-2, a-1] = 1 + mat[a - 1, a - 2] = 1 + mat[a -1, a - 1] = 0 + matrixform *= mat + return matrixform + + + + def coxeter_diagram(self): + """ + This method returns the Coxeter diagram corresponding to a Weyl group. + The Coxeter diagram can be obtained from a Lie algebra's Dynkin diagram + by deleting all arrows; the Coxeter diagram is the undirected graph. + The vertices of the Coxeter diagram represent the generating reflections + of the Weyl group, $s_i$. An edge is drawn between $s_i$ and $s_j$ if the order + $m(i, j)$ of $s_is_j$ is greater than two. If there is one edge, the order + $m(i, j)$ is 3. If there are two edges, the order $m(i, j)$ is 4, and if there + are three edges, the order $m(i, j)$ is 6. + + Examples + ======== + + >>> from sympy.liealgebras.weyl_group import WeylGroup + >>> c = WeylGroup("B3") + >>> print(c.coxeter_diagram()) + 0---0===0 + 1 2 3 + """ + n = self.cartan_type.rank() + if self.cartan_type.series in ("A", "D", "E"): + return self.cartan_type.dynkin_diagram() + + if self.cartan_type.series in ("B", "C"): + diag = "---".join("0" for i in range(1, n)) + "===0\n" + diag += " ".join(str(i) for i in range(1, n+1)) + return diag + + if self.cartan_type.series == "F": + diag = "0---0===0---0\n" + diag += " ".join(str(i) for i in range(1, 5)) + return diag + + if self.cartan_type.series == "G": + diag = "0≡≡≡0\n1 2" + return diag diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..cb26903a384e9df3a0f02a92c488c5442cee1486 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/__init__.py @@ -0,0 +1,12 @@ +from .boolalg import (to_cnf, to_dnf, to_nnf, And, Or, Not, Xor, Nand, Nor, Implies, + Equivalent, ITE, POSform, SOPform, simplify_logic, bool_map, true, false, + gateinputcount) +from .inference import satisfiable + +__all__ = [ + 'to_cnf', 'to_dnf', 'to_nnf', 'And', 'Or', 'Not', 'Xor', 'Nand', 'Nor', + 'Implies', 'Equivalent', 'ITE', 'POSform', 'SOPform', 'simplify_logic', + 'bool_map', 'true', 'false', 'gateinputcount', + + 'satisfiable', +] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/dpll.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/dpll.py new file mode 100644 index 0000000000000000000000000000000000000000..40e6802f7626c982a9a6cd7146baea3ac6b8b6e0 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/dpll.py @@ -0,0 +1,308 @@ +"""Implementation of DPLL algorithm + +Further improvements: eliminate calls to pl_true, implement branching rules, +efficient unit propagation. + +References: + - https://en.wikipedia.org/wiki/DPLL_algorithm + - https://www.researchgate.net/publication/242384772_Implementations_of_the_DPLL_Algorithm +""" + +from sympy.core.sorting import default_sort_key +from sympy.logic.boolalg import Or, Not, conjuncts, disjuncts, to_cnf, \ + to_int_repr, _find_predicates +from sympy.assumptions.cnf import CNF +from sympy.logic.inference import pl_true, literal_symbol + + +def dpll_satisfiable(expr): + """ + Check satisfiability of a propositional sentence. + It returns a model rather than True when it succeeds + + >>> from sympy.abc import A, B + >>> from sympy.logic.algorithms.dpll import dpll_satisfiable + >>> dpll_satisfiable(A & ~B) + {A: True, B: False} + >>> dpll_satisfiable(A & ~A) + False + + """ + if not isinstance(expr, CNF): + clauses = conjuncts(to_cnf(expr)) + else: + clauses = expr.clauses + if False in clauses: + return False + symbols = sorted(_find_predicates(expr), key=default_sort_key) + symbols_int_repr = set(range(1, len(symbols) + 1)) + clauses_int_repr = to_int_repr(clauses, symbols) + result = dpll_int_repr(clauses_int_repr, symbols_int_repr, {}) + if not result: + return result + output = {} + for key in result: + output.update({symbols[key - 1]: result[key]}) + return output + + +def dpll(clauses, symbols, model): + """ + Compute satisfiability in a partial model. + Clauses is an array of conjuncts. + + >>> from sympy.abc import A, B, D + >>> from sympy.logic.algorithms.dpll import dpll + >>> dpll([A, B, D], [A, B], {D: False}) + False + + """ + # compute DP kernel + P, value = find_unit_clause(clauses, model) + while P: + model.update({P: value}) + symbols.remove(P) + if not value: + P = ~P + clauses = unit_propagate(clauses, P) + P, value = find_unit_clause(clauses, model) + P, value = find_pure_symbol(symbols, clauses) + while P: + model.update({P: value}) + symbols.remove(P) + if not value: + P = ~P + clauses = unit_propagate(clauses, P) + P, value = find_pure_symbol(symbols, clauses) + # end DP kernel + unknown_clauses = [] + for c in clauses: + val = pl_true(c, model) + if val is False: + return False + if val is not True: + unknown_clauses.append(c) + if not unknown_clauses: + return model + if not clauses: + return model + P = symbols.pop() + model_copy = model.copy() + model.update({P: True}) + model_copy.update({P: False}) + symbols_copy = symbols[:] + return (dpll(unit_propagate(unknown_clauses, P), symbols, model) or + dpll(unit_propagate(unknown_clauses, Not(P)), symbols_copy, model_copy)) + + +def dpll_int_repr(clauses, symbols, model): + """ + Compute satisfiability in a partial model. + Arguments are expected to be in integer representation + + >>> from sympy.logic.algorithms.dpll import dpll_int_repr + >>> dpll_int_repr([{1}, {2}, {3}], {1, 2}, {3: False}) + False + + """ + # compute DP kernel + P, value = find_unit_clause_int_repr(clauses, model) + while P: + model.update({P: value}) + symbols.remove(P) + if not value: + P = -P + clauses = unit_propagate_int_repr(clauses, P) + P, value = find_unit_clause_int_repr(clauses, model) + P, value = find_pure_symbol_int_repr(symbols, clauses) + while P: + model.update({P: value}) + symbols.remove(P) + if not value: + P = -P + clauses = unit_propagate_int_repr(clauses, P) + P, value = find_pure_symbol_int_repr(symbols, clauses) + # end DP kernel + unknown_clauses = [] + for c in clauses: + val = pl_true_int_repr(c, model) + if val is False: + return False + if val is not True: + unknown_clauses.append(c) + if not unknown_clauses: + return model + P = symbols.pop() + model_copy = model.copy() + model.update({P: True}) + model_copy.update({P: False}) + symbols_copy = symbols.copy() + return (dpll_int_repr(unit_propagate_int_repr(unknown_clauses, P), symbols, model) or + dpll_int_repr(unit_propagate_int_repr(unknown_clauses, -P), symbols_copy, model_copy)) + +### helper methods for DPLL + + +def pl_true_int_repr(clause, model={}): + """ + Lightweight version of pl_true. + Argument clause represents the set of args of an Or clause. This is used + inside dpll_int_repr, it is not meant to be used directly. + + >>> from sympy.logic.algorithms.dpll import pl_true_int_repr + >>> pl_true_int_repr({1, 2}, {1: False}) + >>> pl_true_int_repr({1, 2}, {1: False, 2: False}) + False + + """ + result = False + for lit in clause: + if lit < 0: + p = model.get(-lit) + if p is not None: + p = not p + else: + p = model.get(lit) + if p is True: + return True + elif p is None: + result = None + return result + + +def unit_propagate(clauses, symbol): + """ + Returns an equivalent set of clauses + If a set of clauses contains the unit clause l, the other clauses are + simplified by the application of the two following rules: + + 1. every clause containing l is removed + 2. in every clause that contains ~l this literal is deleted + + Arguments are expected to be in CNF. + + >>> from sympy.abc import A, B, D + >>> from sympy.logic.algorithms.dpll import unit_propagate + >>> unit_propagate([A | B, D | ~B, B], B) + [D, B] + + """ + output = [] + for c in clauses: + if c.func != Or: + output.append(c) + continue + for arg in c.args: + if arg == ~symbol: + output.append(Or(*[x for x in c.args if x != ~symbol])) + break + if arg == symbol: + break + else: + output.append(c) + return output + + +def unit_propagate_int_repr(clauses, s): + """ + Same as unit_propagate, but arguments are expected to be in integer + representation + + >>> from sympy.logic.algorithms.dpll import unit_propagate_int_repr + >>> unit_propagate_int_repr([{1, 2}, {3, -2}, {2}], 2) + [{3}] + + """ + negated = {-s} + return [clause - negated for clause in clauses if s not in clause] + + +def find_pure_symbol(symbols, unknown_clauses): + """ + Find a symbol and its value if it appears only as a positive literal + (or only as a negative) in clauses. + + >>> from sympy.abc import A, B, D + >>> from sympy.logic.algorithms.dpll import find_pure_symbol + >>> find_pure_symbol([A, B, D], [A|~B,~B|~D,D|A]) + (A, True) + + """ + for sym in symbols: + found_pos, found_neg = False, False + for c in unknown_clauses: + if not found_pos and sym in disjuncts(c): + found_pos = True + if not found_neg and Not(sym) in disjuncts(c): + found_neg = True + if found_pos != found_neg: + return sym, found_pos + return None, None + + +def find_pure_symbol_int_repr(symbols, unknown_clauses): + """ + Same as find_pure_symbol, but arguments are expected + to be in integer representation + + >>> from sympy.logic.algorithms.dpll import find_pure_symbol_int_repr + >>> find_pure_symbol_int_repr({1,2,3}, + ... [{1, -2}, {-2, -3}, {3, 1}]) + (1, True) + + """ + all_symbols = set().union(*unknown_clauses) + found_pos = all_symbols.intersection(symbols) + found_neg = all_symbols.intersection([-s for s in symbols]) + for p in found_pos: + if -p not in found_neg: + return p, True + for p in found_neg: + if -p not in found_pos: + return -p, False + return None, None + + +def find_unit_clause(clauses, model): + """ + A unit clause has only 1 variable that is not bound in the model. + + >>> from sympy.abc import A, B, D + >>> from sympy.logic.algorithms.dpll import find_unit_clause + >>> find_unit_clause([A | B | D, B | ~D, A | ~B], {A:True}) + (B, False) + + """ + for clause in clauses: + num_not_in_model = 0 + for literal in disjuncts(clause): + sym = literal_symbol(literal) + if sym not in model: + num_not_in_model += 1 + P, value = sym, not isinstance(literal, Not) + if num_not_in_model == 1: + return P, value + return None, None + + +def find_unit_clause_int_repr(clauses, model): + """ + Same as find_unit_clause, but arguments are expected to be in + integer representation. + + >>> from sympy.logic.algorithms.dpll import find_unit_clause_int_repr + >>> find_unit_clause_int_repr([{1, 2, 3}, + ... {2, -3}, {1, -2}], {1: True}) + (2, False) + + """ + bound = set(model) | {-sym for sym in model} + for clause in clauses: + unbound = clause - bound + if len(unbound) == 1: + p = unbound.pop() + if p < 0: + return -p, False + else: + return p, True + return None, None diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/dpll2.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/dpll2.py new file mode 100644 index 0000000000000000000000000000000000000000..4f18c81189d6be565dc9b7caa3f0bf48e978bb56 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/dpll2.py @@ -0,0 +1,688 @@ +"""Implementation of DPLL algorithm + +Features: + - Clause learning + - Watch literal scheme + - VSIDS heuristic + +References: + - https://en.wikipedia.org/wiki/DPLL_algorithm +""" + +from collections import defaultdict +from heapq import heappush, heappop + +from sympy.core.sorting import ordered +from sympy.assumptions.cnf import EncodedCNF + +from sympy.logic.algorithms.lra_theory import LRASolver + + +def dpll_satisfiable(expr, all_models=False, use_lra_theory=False): + """ + Check satisfiability of a propositional sentence. + It returns a model rather than True when it succeeds. + Returns a generator of all models if all_models is True. + + Examples + ======== + + >>> from sympy.abc import A, B + >>> from sympy.logic.algorithms.dpll2 import dpll_satisfiable + >>> dpll_satisfiable(A & ~B) + {A: True, B: False} + >>> dpll_satisfiable(A & ~A) + False + + """ + if not isinstance(expr, EncodedCNF): + exprs = EncodedCNF() + exprs.add_prop(expr) + expr = exprs + + # Return UNSAT when False (encoded as 0) is present in the CNF + if {0} in expr.data: + if all_models: + return (f for f in [False]) + return False + + if use_lra_theory: + lra, immediate_conflicts = LRASolver.from_encoded_cnf(expr) + else: + lra = None + immediate_conflicts = [] + solver = SATSolver(expr.data + immediate_conflicts, expr.variables, set(), expr.symbols, lra_theory=lra) + models = solver._find_model() + + if all_models: + return _all_models(models) + + try: + return next(models) + except StopIteration: + return False + + # Uncomment to confirm the solution is valid (hitting set for the clauses) + #else: + #for cls in clauses_int_repr: + #assert solver.var_settings.intersection(cls) + + +def _all_models(models): + satisfiable = False + try: + while True: + yield next(models) + satisfiable = True + except StopIteration: + if not satisfiable: + yield False + + +class SATSolver: + """ + Class for representing a SAT solver capable of + finding a model to a boolean theory in conjunctive + normal form. + """ + + def __init__(self, clauses, variables, var_settings, symbols=None, + heuristic='vsids', clause_learning='none', INTERVAL=500, + lra_theory = None): + + self.var_settings = var_settings + self.heuristic = heuristic + self.is_unsatisfied = False + self._unit_prop_queue = [] + self.update_functions = [] + self.INTERVAL = INTERVAL + + if symbols is None: + self.symbols = list(ordered(variables)) + else: + self.symbols = symbols + + self._initialize_variables(variables) + self._initialize_clauses(clauses) + + if 'vsids' == heuristic: + self._vsids_init() + self.heur_calculate = self._vsids_calculate + self.heur_lit_assigned = self._vsids_lit_assigned + self.heur_lit_unset = self._vsids_lit_unset + self.heur_clause_added = self._vsids_clause_added + + # Note: Uncomment this if/when clause learning is enabled + #self.update_functions.append(self._vsids_decay) + + else: + raise NotImplementedError + + if 'simple' == clause_learning: + self.add_learned_clause = self._simple_add_learned_clause + self.compute_conflict = self._simple_compute_conflict + self.update_functions.append(self._simple_clean_clauses) + elif 'none' == clause_learning: + self.add_learned_clause = lambda x: None + self.compute_conflict = lambda: None + else: + raise NotImplementedError + + # Create the base level + self.levels = [Level(0)] + self._current_level.varsettings = var_settings + + # Keep stats + self.num_decisions = 0 + self.num_learned_clauses = 0 + self.original_num_clauses = len(self.clauses) + + self.lra = lra_theory + + def _initialize_variables(self, variables): + """Set up the variable data structures needed.""" + self.sentinels = defaultdict(set) + self.occurrence_count = defaultdict(int) + self.variable_set = [False] * (len(variables) + 1) + + def _initialize_clauses(self, clauses): + """Set up the clause data structures needed. + + For each clause, the following changes are made: + - Unit clauses are queued for propagation right away. + - Non-unit clauses have their first and last literals set as sentinels. + - The number of clauses a literal appears in is computed. + """ + self.clauses = [list(clause) for clause in clauses] + + for i, clause in enumerate(self.clauses): + + # Handle the unit clauses + if 1 == len(clause): + self._unit_prop_queue.append(clause[0]) + continue + + self.sentinels[clause[0]].add(i) + self.sentinels[clause[-1]].add(i) + + for lit in clause: + self.occurrence_count[lit] += 1 + + def _find_model(self): + """ + Main DPLL loop. Returns a generator of models. + + Variables are chosen successively, and assigned to be either + True or False. If a solution is not found with this setting, + the opposite is chosen and the search continues. The solver + halts when every variable has a setting. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + >>> list(l._find_model()) + [{1: True, 2: False, 3: False}, {1: True, 2: True, 3: True}] + + >>> from sympy.abc import A, B, C + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set(), [A, B, C]) + >>> list(l._find_model()) + [{A: True, B: False, C: False}, {A: True, B: True, C: True}] + + """ + + # We use this variable to keep track of if we should flip a + # variable setting in successive rounds + flip_var = False + + # Check if unit prop says the theory is unsat right off the bat + self._simplify() + if self.is_unsatisfied: + return + + # While the theory still has clauses remaining + while True: + # Perform cleanup / fixup at regular intervals + if self.num_decisions % self.INTERVAL == 0: + for func in self.update_functions: + func() + + if flip_var: + # We have just backtracked and we are trying to opposite literal + flip_var = False + lit = self._current_level.decision + + else: + # Pick a literal to set + lit = self.heur_calculate() + self.num_decisions += 1 + + # Stopping condition for a satisfying theory + if 0 == lit: + + # check if assignment satisfies lra theory + if self.lra: + for enc_var in self.var_settings: + res = self.lra.assert_lit(enc_var) + if res is not None: + break + res = self.lra.check() + self.lra.reset_bounds() + else: + res = None + if res is None or res[0]: + yield {self.symbols[abs(lit) - 1]: + lit > 0 for lit in self.var_settings} + else: + self._simple_add_learned_clause(res[1]) + + # backtrack until we unassign one of the literals causing the conflict + while not any(-lit in res[1] for lit in self._current_level.var_settings): + self._undo() + + while self._current_level.flipped: + self._undo() + if len(self.levels) == 1: + return + flip_lit = -self._current_level.decision + self._undo() + self.levels.append(Level(flip_lit, flipped=True)) + flip_var = True + continue + + # Start the new decision level + self.levels.append(Level(lit)) + + # Assign the literal, updating the clauses it satisfies + self._assign_literal(lit) + + # _simplify the theory + self._simplify() + + # Check if we've made the theory unsat + if self.is_unsatisfied: + + self.is_unsatisfied = False + + # We unroll all of the decisions until we can flip a literal + while self._current_level.flipped: + self._undo() + + # If we've unrolled all the way, the theory is unsat + if 1 == len(self.levels): + return + + # Detect and add a learned clause + self.add_learned_clause(self.compute_conflict()) + + # Try the opposite setting of the most recent decision + flip_lit = -self._current_level.decision + self._undo() + self.levels.append(Level(flip_lit, flipped=True)) + flip_var = True + + ######################## + # Helper Methods # + ######################## + @property + def _current_level(self): + """The current decision level data structure + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{1}, {2}], {1, 2}, set()) + >>> next(l._find_model()) + {1: True, 2: True} + >>> l._current_level.decision + 0 + >>> l._current_level.flipped + False + >>> l._current_level.var_settings + {1, 2} + + """ + return self.levels[-1] + + def _clause_sat(self, cls): + """Check if a clause is satisfied by the current variable setting. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{1}, {-1}], {1}, set()) + >>> try: + ... next(l._find_model()) + ... except StopIteration: + ... pass + >>> l._clause_sat(0) + False + >>> l._clause_sat(1) + True + + """ + for lit in self.clauses[cls]: + if lit in self.var_settings: + return True + return False + + def _is_sentinel(self, lit, cls): + """Check if a literal is a sentinel of a given clause. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + >>> next(l._find_model()) + {1: True, 2: False, 3: False} + >>> l._is_sentinel(2, 3) + True + >>> l._is_sentinel(-3, 1) + False + + """ + return cls in self.sentinels[lit] + + def _assign_literal(self, lit): + """Make a literal assignment. + + The literal assignment must be recorded as part of the current + decision level. Additionally, if the literal is marked as a + sentinel of any clause, then a new sentinel must be chosen. If + this is not possible, then unit propagation is triggered and + another literal is added to the queue to be set in the future. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + >>> next(l._find_model()) + {1: True, 2: False, 3: False} + >>> l.var_settings + {-3, -2, 1} + + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + >>> l._assign_literal(-1) + >>> try: + ... next(l._find_model()) + ... except StopIteration: + ... pass + >>> l.var_settings + {-1} + + """ + self.var_settings.add(lit) + self._current_level.var_settings.add(lit) + self.variable_set[abs(lit)] = True + self.heur_lit_assigned(lit) + + sentinel_list = list(self.sentinels[-lit]) + + for cls in sentinel_list: + if not self._clause_sat(cls): + other_sentinel = None + for newlit in self.clauses[cls]: + if newlit != -lit: + if self._is_sentinel(newlit, cls): + other_sentinel = newlit + elif not self.variable_set[abs(newlit)]: + self.sentinels[-lit].remove(cls) + self.sentinels[newlit].add(cls) + other_sentinel = None + break + + # Check if no sentinel update exists + if other_sentinel: + self._unit_prop_queue.append(other_sentinel) + + def _undo(self): + """ + _undo the changes of the most recent decision level. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + >>> next(l._find_model()) + {1: True, 2: False, 3: False} + >>> level = l._current_level + >>> level.decision, level.var_settings, level.flipped + (-3, {-3, -2}, False) + >>> l._undo() + >>> level = l._current_level + >>> level.decision, level.var_settings, level.flipped + (0, {1}, False) + + """ + # Undo the variable settings + for lit in self._current_level.var_settings: + self.var_settings.remove(lit) + self.heur_lit_unset(lit) + self.variable_set[abs(lit)] = False + + # Pop the level off the stack + self.levels.pop() + + ######################### + # Propagation # + ######################### + """ + Propagation methods should attempt to soundly simplify the boolean + theory, and return True if any simplification occurred and False + otherwise. + """ + def _simplify(self): + """Iterate over the various forms of propagation to simplify the theory. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + >>> l.variable_set + [False, False, False, False] + >>> l.sentinels + {-3: {0, 2}, -2: {3, 4}, 2: {0, 3}, 3: {2, 4}} + + >>> l._simplify() + + >>> l.variable_set + [False, True, False, False] + >>> l.sentinels + {-3: {0, 2}, -2: {3, 4}, -1: set(), 2: {0, 3}, + ...3: {2, 4}} + + """ + changed = True + while changed: + changed = False + changed |= self._unit_prop() + changed |= self._pure_literal() + + def _unit_prop(self): + """Perform unit propagation on the current theory.""" + result = len(self._unit_prop_queue) > 0 + while self._unit_prop_queue: + next_lit = self._unit_prop_queue.pop() + if -next_lit in self.var_settings: + self.is_unsatisfied = True + self._unit_prop_queue = [] + return False + else: + self._assign_literal(next_lit) + + return result + + def _pure_literal(self): + """Look for pure literals and assign them when found.""" + return False + + ######################### + # Heuristics # + ######################### + def _vsids_init(self): + """Initialize the data structures needed for the VSIDS heuristic.""" + self.lit_heap = [] + self.lit_scores = {} + + for var in range(1, len(self.variable_set)): + self.lit_scores[var] = float(-self.occurrence_count[var]) + self.lit_scores[-var] = float(-self.occurrence_count[-var]) + heappush(self.lit_heap, (self.lit_scores[var], var)) + heappush(self.lit_heap, (self.lit_scores[-var], -var)) + + def _vsids_decay(self): + """Decay the VSIDS scores for every literal. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + + >>> l.lit_scores + {-3: -2.0, -2: -2.0, -1: 0.0, 1: 0.0, 2: -2.0, 3: -2.0} + + >>> l._vsids_decay() + + >>> l.lit_scores + {-3: -1.0, -2: -1.0, -1: 0.0, 1: 0.0, 2: -1.0, 3: -1.0} + + """ + # We divide every literal score by 2 for a decay factor + # Note: This doesn't change the heap property + for lit in self.lit_scores.keys(): + self.lit_scores[lit] /= 2.0 + + def _vsids_calculate(self): + """ + VSIDS Heuristic Calculation + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + + >>> l.lit_heap + [(-2.0, -3), (-2.0, 2), (-2.0, -2), (0.0, 1), (-2.0, 3), (0.0, -1)] + + >>> l._vsids_calculate() + -3 + + >>> l.lit_heap + [(-2.0, -2), (-2.0, 2), (0.0, -1), (0.0, 1), (-2.0, 3)] + + """ + if len(self.lit_heap) == 0: + return 0 + + # Clean out the front of the heap as long the variables are set + while self.variable_set[abs(self.lit_heap[0][1])]: + heappop(self.lit_heap) + if len(self.lit_heap) == 0: + return 0 + + return heappop(self.lit_heap)[1] + + def _vsids_lit_assigned(self, lit): + """Handle the assignment of a literal for the VSIDS heuristic.""" + pass + + def _vsids_lit_unset(self, lit): + """Handle the unsetting of a literal for the VSIDS heuristic. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + >>> l.lit_heap + [(-2.0, -3), (-2.0, 2), (-2.0, -2), (0.0, 1), (-2.0, 3), (0.0, -1)] + + >>> l._vsids_lit_unset(2) + + >>> l.lit_heap + [(-2.0, -3), (-2.0, -2), (-2.0, -2), (-2.0, 2), (-2.0, 3), (0.0, -1), + ...(-2.0, 2), (0.0, 1)] + + """ + var = abs(lit) + heappush(self.lit_heap, (self.lit_scores[var], var)) + heappush(self.lit_heap, (self.lit_scores[-var], -var)) + + def _vsids_clause_added(self, cls): + """Handle the addition of a new clause for the VSIDS heuristic. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + + >>> l.num_learned_clauses + 0 + >>> l.lit_scores + {-3: -2.0, -2: -2.0, -1: 0.0, 1: 0.0, 2: -2.0, 3: -2.0} + + >>> l._vsids_clause_added({2, -3}) + + >>> l.num_learned_clauses + 1 + >>> l.lit_scores + {-3: -1.0, -2: -2.0, -1: 0.0, 1: 0.0, 2: -1.0, 3: -2.0} + + """ + self.num_learned_clauses += 1 + for lit in cls: + self.lit_scores[lit] += 1 + + ######################## + # Clause Learning # + ######################## + def _simple_add_learned_clause(self, cls): + """Add a new clause to the theory. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + + >>> l.num_learned_clauses + 0 + >>> l.clauses + [[2, -3], [1], [3, -3], [2, -2], [3, -2]] + >>> l.sentinels + {-3: {0, 2}, -2: {3, 4}, 2: {0, 3}, 3: {2, 4}} + + >>> l._simple_add_learned_clause([3]) + + >>> l.clauses + [[2, -3], [1], [3, -3], [2, -2], [3, -2], [3]] + >>> l.sentinels + {-3: {0, 2}, -2: {3, 4}, 2: {0, 3}, 3: {2, 4, 5}} + + """ + cls_num = len(self.clauses) + self.clauses.append(cls) + + for lit in cls: + self.occurrence_count[lit] += 1 + + self.sentinels[cls[0]].add(cls_num) + self.sentinels[cls[-1]].add(cls_num) + + self.heur_clause_added(cls) + + def _simple_compute_conflict(self): + """ Build a clause representing the fact that at least one decision made + so far is wrong. + + Examples + ======== + + >>> from sympy.logic.algorithms.dpll2 import SATSolver + >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2}, + ... {3, -2}], {1, 2, 3}, set()) + >>> next(l._find_model()) + {1: True, 2: False, 3: False} + >>> l._simple_compute_conflict() + [3] + + """ + return [-(level.decision) for level in self.levels[1:]] + + def _simple_clean_clauses(self): + """Clean up learned clauses.""" + pass + + +class Level: + """ + Represents a single level in the DPLL algorithm, and contains + enough information for a sound backtracking procedure. + """ + + def __init__(self, decision, flipped=False): + self.decision = decision + self.var_settings = set() + self.flipped = flipped diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/lra_theory.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/lra_theory.py new file mode 100644 index 0000000000000000000000000000000000000000..1690760d36003aed6866f593120c05a5b8f92c83 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/lra_theory.py @@ -0,0 +1,912 @@ +"""Implements "A Fast Linear-Arithmetic Solver for DPLL(T)" + +The LRASolver class defined in this file can be used +in conjunction with a SAT solver to check the +satisfiability of formulas involving inequalities. + +Here's an example of how that would work: + + Suppose you want to check the satisfiability of + the following formula: + + >>> from sympy.core.relational import Eq + >>> from sympy.abc import x, y + >>> f = ((x > 0) | (x < 0)) & (Eq(x, 0) | Eq(y, 1)) & (~Eq(y, 1) | Eq(1, 2)) + + First a preprocessing step should be done on f. During preprocessing, + f should be checked for any predicates such as `Q.prime` that can't be + handled. Also unequality like `~Eq(y, 1)` should be split. + + I should mention that the paper says to split both equalities and + unequality, but this implementation only requires that unequality + be split. + + >>> f = ((x > 0) | (x < 0)) & (Eq(x, 0) | Eq(y, 1)) & ((y < 1) | (y > 1) | Eq(1, 2)) + + Then an LRASolver instance needs to be initialized with this formula. + + >>> from sympy.assumptions.cnf import CNF, EncodedCNF + >>> from sympy.assumptions.ask import Q + >>> from sympy.logic.algorithms.lra_theory import LRASolver + >>> cnf = CNF.from_prop(f) + >>> enc = EncodedCNF() + >>> enc.add_from_cnf(cnf) + >>> lra, conflicts = LRASolver.from_encoded_cnf(enc) + + Any immediate one-lital conflicts clauses will be detected here. + In this example, `~Eq(1, 2)` is one such conflict clause. We'll + want to add it to `f` so that the SAT solver is forced to + assign Eq(1, 2) to False. + + >>> f = f & ~Eq(1, 2) + + Now that the one-literal conflict clauses have been added + and an lra object has been initialized, we can pass `f` + to a SAT solver. The SAT solver will give us a satisfying + assignment such as: + + (1 = 2): False + (y = 1): True + (y < 1): True + (y > 1): True + (x = 0): True + (x < 0): True + (x > 0): True + + Next you would pass this assignment to the LRASolver + which will be able to determine that this particular + assignment is satisfiable or not. + + Note that since EncodedCNF is inherently non-deterministic, + the int each predicate is encoded as is not consistent. As a + result, the code below likely does not reflect the assignment + given above. + + >>> lra.assert_lit(-1) #doctest: +SKIP + >>> lra.assert_lit(2) #doctest: +SKIP + >>> lra.assert_lit(3) #doctest: +SKIP + >>> lra.assert_lit(4) #doctest: +SKIP + >>> lra.assert_lit(5) #doctest: +SKIP + >>> lra.assert_lit(6) #doctest: +SKIP + >>> lra.assert_lit(7) #doctest: +SKIP + >>> is_sat, conflict_or_assignment = lra.check() + + As the particular assignment suggested is not satisfiable, + the LRASolver will return unsat and a conflict clause when + given that assignment. The conflict clause will always be + minimal, but there can be multiple minimal conflict clauses. + One possible conflict clause could be `~(x < 0) | ~(x > 0)`. + + We would then add whatever conflict clause is given to + `f` to prevent the SAT solver from coming up with an + assignment with the same conflicting literals. In this case, + the conflict clause `~(x < 0) | ~(x > 0)` would prevent + any assignment where both (x < 0) and (x > 0) were both + true. + + The SAT solver would then find another assignment + and we would check that assignment with the LRASolver + and so on. Eventually either a satisfying assignment + that the SAT solver and LRASolver agreed on would be found + or enough conflict clauses would be added so that the + boolean formula was unsatisfiable. + + +This implementation is based on [1]_, which includes a +detailed explanation of the algorithm and pseudocode +for the most important functions. + +[1]_ also explains how backtracking and theory propagation +could be implemented to speed up the current implementation, +but these are not currently implemented. + +TODO: + - Handle non-rational real numbers + - Handle positive and negative infinity + - Implement backtracking and theory proposition + - Simplify matrix by removing unused variables using Gaussian elimination + +References +========== + +.. [1] Dutertre, B., de Moura, L.: + A Fast Linear-Arithmetic Solver for DPLL(T) + https://link.springer.com/chapter/10.1007/11817963_11 +""" +from sympy.solvers.solveset import linear_eq_to_matrix +from sympy.matrices.dense import eye +from sympy.assumptions import Predicate +from sympy.assumptions.assume import AppliedPredicate +from sympy.assumptions.ask import Q +from sympy.core import Dummy +from sympy.core.mul import Mul +from sympy.core.add import Add +from sympy.core.relational import Eq, Ne +from sympy.core.sympify import sympify +from sympy.core.singleton import S +from sympy.core.numbers import Rational, oo +from sympy.matrices.dense import Matrix + +class UnhandledInput(Exception): + """ + Raised while creating an LRASolver if non-linearity + or non-rational numbers are present. + """ + +# predicates that LRASolver understands and makes use of +ALLOWED_PRED = {Q.eq, Q.gt, Q.lt, Q.le, Q.ge} + +# if true ~Q.gt(x, y) implies Q.le(x, y) +HANDLE_NEGATION = True + +class LRASolver(): + """ + Linear Arithmetic Solver for DPLL(T) implemented with an algorithm based on + the Dual Simplex method. Uses Bland's pivoting rule to avoid cycling. + + References + ========== + + .. [1] Dutertre, B., de Moura, L.: + A Fast Linear-Arithmetic Solver for DPLL(T) + https://link.springer.com/chapter/10.1007/11817963_11 + """ + + def __init__(self, A, slack_variables, nonslack_variables, enc_to_boundary, s_subs, testing_mode): + """ + Use the "from_encoded_cnf" method to create a new LRASolver. + """ + self.run_checks = testing_mode + self.s_subs = s_subs # used only for test_lra_theory.test_random_problems + + if any(not isinstance(a, Rational) for a in A): + raise UnhandledInput("Non-rational numbers are not handled") + if any(not isinstance(b.bound, Rational) for b in enc_to_boundary.values()): + raise UnhandledInput("Non-rational numbers are not handled") + m, n = len(slack_variables), len(slack_variables)+len(nonslack_variables) + if m != 0: + assert A.shape == (m, n) + if self.run_checks: + assert A[:, n-m:] == -eye(m) + + self.enc_to_boundary = enc_to_boundary # mapping of int to Boundary objects + self.boundary_to_enc = {value: key for key, value in enc_to_boundary.items()} + self.A = A + self.slack = slack_variables + self.nonslack = nonslack_variables + self.all_var = nonslack_variables + slack_variables + + self.slack_set = set(slack_variables) + + self.is_sat = True # While True, all constraints asserted so far are satisfiable + self.result = None # always one of: (True, assignment), (False, conflict clause), None + + @staticmethod + def from_encoded_cnf(encoded_cnf, testing_mode=False): + """ + Creates an LRASolver from an EncodedCNF object + and a list of conflict clauses for propositions + that can be simplified to True or False. + + Parameters + ========== + + encoded_cnf : EncodedCNF + + testing_mode : bool + Setting testing_mode to True enables some slow assert statements + and sorting to reduce nonterministic behavior. + + Returns + ======= + + (lra, conflicts) + + lra : LRASolver + + conflicts : list + Contains a one-literal conflict clause for each proposition + that can be simplified to True or False. + + Example + ======= + + >>> from sympy.core.relational import Eq + >>> from sympy.assumptions.cnf import CNF, EncodedCNF + >>> from sympy.assumptions.ask import Q + >>> from sympy.logic.algorithms.lra_theory import LRASolver + >>> from sympy.abc import x, y, z + >>> phi = (x >= 0) & ((x + y <= 2) | (x + 2 * y - z >= 6)) + >>> phi = phi & (Eq(x + y, 2) | (x + 2 * y - z > 4)) + >>> phi = phi & Q.gt(2, 1) + >>> cnf = CNF.from_prop(phi) + >>> enc = EncodedCNF() + >>> enc.from_cnf(cnf) + >>> lra, conflicts = LRASolver.from_encoded_cnf(enc, testing_mode=True) + >>> lra #doctest: +SKIP + + >>> conflicts #doctest: +SKIP + [[4]] + """ + # This function has three main jobs: + # - raise errors if the input formula is not handled + # - preprocesses the formula into a matrix and single variable constraints + # - create one-literal conflict clauses from predicates that are always True + # or always False such as Q.gt(3, 2) + # + # See the preprocessing section of "A Fast Linear-Arithmetic Solver for DPLL(T)" + # for an explanation of how the formula is converted into a matrix + # and a set of single variable constraints. + + encoding = {} # maps int to boundary + A = [] + + basic = [] + s_count = 0 + s_subs = {} + nonbasic = [] + + if testing_mode: + # sort to reduce nondeterminism + encoded_cnf_items = sorted(encoded_cnf.encoding.items(), key=lambda x: str(x)) + else: + encoded_cnf_items = encoded_cnf.encoding.items() + + empty_var = Dummy() + var_to_lra_var = {} + conflicts = [] + + for prop, enc in encoded_cnf_items: + if isinstance(prop, Predicate): + prop = prop(empty_var) + if not isinstance(prop, AppliedPredicate): + if prop == True: + conflicts.append([enc]) + continue + if prop == False: + conflicts.append([-enc]) + continue + + raise ValueError(f"Unhandled Predicate: {prop}") + + assert prop.function in ALLOWED_PRED + if prop.lhs == S.NaN or prop.rhs == S.NaN: + raise ValueError(f"{prop} contains nan") + if prop.lhs.is_imaginary or prop.rhs.is_imaginary: + raise UnhandledInput(f"{prop} contains an imaginary component") + if prop.lhs == oo or prop.rhs == oo: + raise UnhandledInput(f"{prop} contains infinity") + + prop = _eval_binrel(prop) # simplify variable-less quantities to True / False if possible + if prop == True: + conflicts.append([enc]) + continue + elif prop == False: + conflicts.append([-enc]) + continue + elif prop is None: + raise UnhandledInput(f"{prop} could not be simplified") + + expr = prop.lhs - prop.rhs + if prop.function in [Q.ge, Q.gt]: + expr = -expr + + # expr should be less than (or equal to) 0 + # otherwise prop is False + if prop.function in [Q.le, Q.ge]: + bool = (expr <= 0) + elif prop.function in [Q.lt, Q.gt]: + bool = (expr < 0) + else: + assert prop.function == Q.eq + bool = Eq(expr, 0) + + if bool == True: + conflicts.append([enc]) + continue + elif bool == False: + conflicts.append([-enc]) + continue + + + vars, const = _sep_const_terms(expr) # example: (2x + 3y + 2) --> (2x + 3y), (2) + vars, var_coeff = _sep_const_coeff(vars) # examples: (2x) --> (x, 2); (2x + 3y) --> (2x + 3y), (1) + const = const / var_coeff + + terms = _list_terms(vars) # example: (2x + 3y) --> [2x, 3y] + for term in terms: + term, _ = _sep_const_coeff(term) + assert len(term.free_symbols) > 0 + if term not in var_to_lra_var: + var_to_lra_var[term] = LRAVariable(term) + nonbasic.append(term) + + if len(terms) > 1: + if vars not in s_subs: + s_count += 1 + d = Dummy(f"s{s_count}") + var_to_lra_var[d] = LRAVariable(d) + basic.append(d) + s_subs[vars] = d + A.append(vars - d) + var = s_subs[vars] + else: + var = terms[0] + + assert var_coeff != 0 + + equality = prop.function == Q.eq + upper = var_coeff > 0 if not equality else None + strict = prop.function in [Q.gt, Q.lt] + b = Boundary(var_to_lra_var[var], -const, upper, equality, strict) + encoding[enc] = b + + fs = [v.free_symbols for v in nonbasic + basic] + assert all(len(syms) > 0 for syms in fs) + fs_count = sum(len(syms) for syms in fs) + if len(fs) > 0 and len(set.union(*fs)) < fs_count: + raise UnhandledInput("Nonlinearity is not handled") + + A, _ = linear_eq_to_matrix(A, nonbasic + basic) + nonbasic = [var_to_lra_var[nb] for nb in nonbasic] + basic = [var_to_lra_var[b] for b in basic] + for idx, var in enumerate(nonbasic + basic): + var.col_idx = idx + + return LRASolver(A, basic, nonbasic, encoding, s_subs, testing_mode), conflicts + + def reset_bounds(self): + """ + Resets the state of the LRASolver to before + anything was asserted. + """ + self.result = None + for var in self.all_var: + var.lower = LRARational(-float("inf"), 0) + var.lower_from_eq = False + var.lower_from_neg = False + var.upper = LRARational(float("inf"), 0) + var.upper_from_eq= False + var.lower_from_neg = False + var.assign = LRARational(0, 0) + + def assert_lit(self, enc_constraint): + """ + Assert a literal representing a constraint + and update the internal state accordingly. + + Note that due to peculiarities of this implementation + asserting ~(x > 0) will assert (x <= 0) but asserting + ~Eq(x, 0) will not do anything. + + Parameters + ========== + + enc_constraint : int + A mapping of encodings to constraints + can be found in `self.enc_to_boundary`. + + Returns + ======= + + None or (False, explanation) + + explanation : set of ints + A conflict clause that "explains" why + the literals asserted so far are unsatisfiable. + """ + if abs(enc_constraint) not in self.enc_to_boundary: + return None + + if not HANDLE_NEGATION and enc_constraint < 0: + return None + + boundary = self.enc_to_boundary[abs(enc_constraint)] + sym, c, negated = boundary.var, boundary.bound, enc_constraint < 0 + + if boundary.equality and negated: + return None # negated equality is not handled and should only appear in conflict clauses + + upper = boundary.upper != negated + if boundary.strict != negated: + delta = -1 if upper else 1 + c = LRARational(c, delta) + else: + c = LRARational(c, 0) + + if boundary.equality: + res1 = self._assert_lower(sym, c, from_equality=True, from_neg=negated) + if res1 and res1[0] == False: + res = res1 + else: + res2 = self._assert_upper(sym, c, from_equality=True, from_neg=negated) + res = res2 + elif upper: + res = self._assert_upper(sym, c, from_neg=negated) + else: + res = self._assert_lower(sym, c, from_neg=negated) + + if self.is_sat and sym not in self.slack_set: + self.is_sat = res is None + else: + self.is_sat = False + + return res + + def _assert_upper(self, xi, ci, from_equality=False, from_neg=False): + """ + Adjusts the upper bound on variable xi if the new upper bound is + more limiting. The assignment of variable xi is adjusted to be + within the new bound if needed. + + Also calls `self._update` to update the assignment for slack variables + to keep all equalities satisfied. + """ + if self.result: + assert self.result[0] != False + self.result = None + if ci >= xi.upper: + return None + if ci < xi.lower: + assert (xi.lower[1] >= 0) is True + assert (ci[1] <= 0) is True + + lit1, neg1 = Boundary.from_lower(xi) + + lit2 = Boundary(var=xi, const=ci[0], strict=ci[1] != 0, upper=True, equality=from_equality) + if from_neg: + lit2 = lit2.get_negated() + neg2 = -1 if from_neg else 1 + + conflict = [-neg1*self.boundary_to_enc[lit1], -neg2*self.boundary_to_enc[lit2]] + self.result = False, conflict + return self.result + xi.upper = ci + xi.upper_from_eq = from_equality + xi.upper_from_neg = from_neg + if xi in self.nonslack and xi.assign > ci: + self._update(xi, ci) + + if self.run_checks and all(v.assign[0] != float("inf") and v.assign[0] != -float("inf") + for v in self.all_var): + M = self.A + X = Matrix([v.assign[0] for v in self.all_var]) + assert all(abs(val) < 10 ** (-10) for val in M * X) + + return None + + def _assert_lower(self, xi, ci, from_equality=False, from_neg=False): + """ + Adjusts the lower bound on variable xi if the new lower bound is + more limiting. The assignment of variable xi is adjusted to be + within the new bound if needed. + + Also calls `self._update` to update the assignment for slack variables + to keep all equalities satisfied. + """ + if self.result: + assert self.result[0] != False + self.result = None + if ci <= xi.lower: + return None + if ci > xi.upper: + assert (xi.upper[1] <= 0) is True + assert (ci[1] >= 0) is True + + lit1, neg1 = Boundary.from_upper(xi) + + lit2 = Boundary(var=xi, const=ci[0], strict=ci[1] != 0, upper=False, equality=from_equality) + if from_neg: + lit2 = lit2.get_negated() + neg2 = -1 if from_neg else 1 + + conflict = [-neg1*self.boundary_to_enc[lit1],-neg2*self.boundary_to_enc[lit2]] + self.result = False, conflict + return self.result + xi.lower = ci + xi.lower_from_eq = from_equality + xi.lower_from_neg = from_neg + if xi in self.nonslack and xi.assign < ci: + self._update(xi, ci) + + if self.run_checks and all(v.assign[0] != float("inf") and v.assign[0] != -float("inf") + for v in self.all_var): + M = self.A + X = Matrix([v.assign[0] for v in self.all_var]) + assert all(abs(val) < 10 ** (-10) for val in M * X) + + return None + + def _update(self, xi, v): + """ + Updates all slack variables that have equations that contain + variable xi so that they stay satisfied given xi is equal to v. + """ + i = xi.col_idx + for j, b in enumerate(self.slack): + aji = self.A[j, i] + b.assign = b.assign + (v - xi.assign)*aji + xi.assign = v + + def check(self): + """ + Searches for an assignment that satisfies all constraints + or determines that no such assignment exists and gives + a minimal conflict clause that "explains" why the + constraints are unsatisfiable. + + Returns + ======= + + (True, assignment) or (False, explanation) + + assignment : dict of LRAVariables to values + Assigned values are tuples that represent a rational number + plus some infinatesimal delta. + + explanation : set of ints + """ + if self.is_sat: + return True, {var: var.assign for var in self.all_var} + if self.result: + return self.result + + from sympy.matrices.dense import Matrix + M = self.A.copy() + basic = {s: i for i, s in enumerate(self.slack)} # contains the row index associated with each basic variable + nonbasic = set(self.nonslack) + while True: + if self.run_checks: + # nonbasic variables must always be within bounds + assert all(((nb.assign >= nb.lower) == True) and ((nb.assign <= nb.upper) == True) for nb in nonbasic) + + # assignments for x must always satisfy Ax = 0 + # probably have to turn this off when dealing with strict ineq + if all(v.assign[0] != float("inf") and v.assign[0] != -float("inf") + for v in self.all_var): + X = Matrix([v.assign[0] for v in self.all_var]) + assert all(abs(val) < 10**(-10) for val in M*X) + + # check upper and lower match this format: + # x <= rat + delta iff x < rat + # x >= rat - delta iff x > rat + # this wouldn't make sense: + # x <= rat - delta + # x >= rat + delta + assert all(x.upper[1] <= 0 for x in self.all_var) + assert all(x.lower[1] >= 0 for x in self.all_var) + + cand = [b for b in basic if b.assign < b.lower or b.assign > b.upper] + + if len(cand) == 0: + return True, {var: var.assign for var in self.all_var} + + xi = min(cand, key=lambda v: v.col_idx) # Bland's rule + i = basic[xi] + + if xi.assign < xi.lower: + cand = [nb for nb in nonbasic + if (M[i, nb.col_idx] > 0 and nb.assign < nb.upper) + or (M[i, nb.col_idx] < 0 and nb.assign > nb.lower)] + if len(cand) == 0: + N_plus = [nb for nb in nonbasic if M[i, nb.col_idx] > 0] + N_minus = [nb for nb in nonbasic if M[i, nb.col_idx] < 0] + + conflict = [] + conflict += [Boundary.from_upper(nb) for nb in N_plus] + conflict += [Boundary.from_lower(nb) for nb in N_minus] + conflict.append(Boundary.from_lower(xi)) + conflict = [-neg*self.boundary_to_enc[c] for c, neg in conflict] + return False, conflict + xj = min(cand, key=str) + M = self._pivot_and_update(M, basic, nonbasic, xi, xj, xi.lower) + + if xi.assign > xi.upper: + cand = [nb for nb in nonbasic + if (M[i, nb.col_idx] < 0 and nb.assign < nb.upper) + or (M[i, nb.col_idx] > 0 and nb.assign > nb.lower)] + + if len(cand) == 0: + N_plus = [nb for nb in nonbasic if M[i, nb.col_idx] > 0] + N_minus = [nb for nb in nonbasic if M[i, nb.col_idx] < 0] + + conflict = [] + conflict += [Boundary.from_upper(nb) for nb in N_minus] + conflict += [Boundary.from_lower(nb) for nb in N_plus] + conflict.append(Boundary.from_upper(xi)) + + conflict = [-neg*self.boundary_to_enc[c] for c, neg in conflict] + return False, conflict + xj = min(cand, key=lambda v: v.col_idx) + M = self._pivot_and_update(M, basic, nonbasic, xi, xj, xi.upper) + + def _pivot_and_update(self, M, basic, nonbasic, xi, xj, v): + """ + Pivots basic variable xi with nonbasic variable xj, + and sets value of xi to v and adjusts the values of all basic variables + to keep equations satisfied. + """ + i, j = basic[xi], xj.col_idx + assert M[i, j] != 0 + theta = (v - xi.assign)*(1/M[i, j]) + xi.assign = v + xj.assign = xj.assign + theta + for xk in basic: + if xk != xi: + k = basic[xk] + akj = M[k, j] + xk.assign = xk.assign + theta*akj + # pivot + basic[xj] = basic[xi] + del basic[xi] + nonbasic.add(xi) + nonbasic.remove(xj) + return self._pivot(M, i, j) + + @staticmethod + def _pivot(M, i, j): + """ + Performs a pivot operation about entry i, j of M by performing + a series of row operations on a copy of M and returning the result. + The original M is left unmodified. + + Conceptually, M represents a system of equations and pivoting + can be thought of as rearranging equation i to be in terms of + variable j and then substituting in the rest of the equations + to get rid of other occurances of variable j. + + Example + ======= + + >>> from sympy.matrices.dense import Matrix + >>> from sympy.logic.algorithms.lra_theory import LRASolver + >>> from sympy import var + >>> Matrix(3, 3, var('a:i')) + Matrix([ + [a, b, c], + [d, e, f], + [g, h, i]]) + + This matrix is equivalent to: + 0 = a*x + b*y + c*z + 0 = d*x + e*y + f*z + 0 = g*x + h*y + i*z + + >>> LRASolver._pivot(_, 1, 0) + Matrix([ + [ 0, -a*e/d + b, -a*f/d + c], + [-1, -e/d, -f/d], + [ 0, h - e*g/d, i - f*g/d]]) + + We rearrange equation 1 in terms of variable 0 (x) + and substitute to remove x from the other equations. + + 0 = 0 + (-a*e/d + b)*y + (-a*f/d + c)*z + 0 = -x + (-e/d)*y + (-f/d)*z + 0 = 0 + (h - e*g/d)*y + (i - f*g/d)*z + """ + _, _, Mij = M[i, :], M[:, j], M[i, j] + if Mij == 0: + raise ZeroDivisionError("Tried to pivot about zero-valued entry.") + A = M.copy() + A[i, :] = -A[i, :]/Mij + for row in range(M.shape[0]): + if row != i: + A[row, :] = A[row, :] + A[row, j] * A[i, :] + + return A + + +def _sep_const_coeff(expr): + """ + Example + ======= + + >>> from sympy.logic.algorithms.lra_theory import _sep_const_coeff + >>> from sympy.abc import x, y + >>> _sep_const_coeff(2*x) + (x, 2) + >>> _sep_const_coeff(2*x + 3*y) + (2*x + 3*y, 1) + """ + if isinstance(expr, Add): + return expr, sympify(1) + + if isinstance(expr, Mul): + coeffs = expr.args + else: + coeffs = [expr] + + var, const = [], [] + for c in coeffs: + c = sympify(c) + if len(c.free_symbols)==0: + const.append(c) + else: + var.append(c) + return Mul(*var), Mul(*const) + + +def _list_terms(expr): + if not isinstance(expr, Add): + return [expr] + + return expr.args + + +def _sep_const_terms(expr): + """ + Example + ======= + + >>> from sympy.logic.algorithms.lra_theory import _sep_const_terms + >>> from sympy.abc import x, y + >>> _sep_const_terms(2*x + 3*y + 2) + (2*x + 3*y, 2) + """ + if isinstance(expr, Add): + terms = expr.args + else: + terms = [expr] + + var, const = [], [] + for t in terms: + if len(t.free_symbols) == 0: + const.append(t) + else: + var.append(t) + return sum(var), sum(const) + + +def _eval_binrel(binrel): + """ + Simplify binary relation to True / False if possible. + """ + if not (len(binrel.lhs.free_symbols) == 0 and len(binrel.rhs.free_symbols) == 0): + return binrel + if binrel.function == Q.lt: + res = binrel.lhs < binrel.rhs + elif binrel.function == Q.gt: + res = binrel.lhs > binrel.rhs + elif binrel.function == Q.le: + res = binrel.lhs <= binrel.rhs + elif binrel.function == Q.ge: + res = binrel.lhs >= binrel.rhs + elif binrel.function == Q.eq: + res = Eq(binrel.lhs, binrel.rhs) + elif binrel.function == Q.ne: + res = Ne(binrel.lhs, binrel.rhs) + + if res == True or res == False: + return res + else: + return None + + +class Boundary: + """ + Represents an upper or lower bound or an equality between a symbol + and some constant. + """ + def __init__(self, var, const, upper, equality, strict=None): + if not equality in [True, False]: + assert equality in [True, False] + + + self.var = var + if isinstance(const, tuple): + s = const[1] != 0 + if strict: + assert s == strict + self.bound = const[0] + self.strict = s + else: + self.bound = const + self.strict = strict + self.upper = upper if not equality else None + self.equality = equality + self.strict = strict + assert self.strict is not None + + @staticmethod + def from_upper(var): + neg = -1 if var.upper_from_neg else 1 + b = Boundary(var, var.upper[0], True, var.upper_from_eq, var.upper[1] != 0) + if neg < 0: + b = b.get_negated() + return b, neg + + @staticmethod + def from_lower(var): + neg = -1 if var.lower_from_neg else 1 + b = Boundary(var, var.lower[0], False, var.lower_from_eq, var.lower[1] != 0) + if neg < 0: + b = b.get_negated() + return b, neg + + def get_negated(self): + return Boundary(self.var, self.bound, not self.upper, self.equality, not self.strict) + + def get_inequality(self): + if self.equality: + return Eq(self.var.var, self.bound) + elif self.upper and self.strict: + return self.var.var < self.bound + elif not self.upper and self.strict: + return self.var.var > self.bound + elif self.upper: + return self.var.var <= self.bound + else: + return self.var.var >= self.bound + + def __repr__(self): + return repr("Boundary(" + repr(self.get_inequality()) + ")") + + def __eq__(self, other): + other = (other.var, other.bound, other.strict, other.upper, other.equality) + return (self.var, self.bound, self.strict, self.upper, self.equality) == other + + def __hash__(self): + return hash((self.var, self.bound, self.strict, self.upper, self.equality)) + + +class LRARational(): + """ + Represents a rational plus or minus some amount + of arbitrary small deltas. + """ + def __init__(self, rational, delta): + self.value = (rational, delta) + + def __lt__(self, other): + return self.value < other.value + + def __le__(self, other): + return self.value <= other.value + + def __eq__(self, other): + return self.value == other.value + + def __add__(self, other): + return LRARational(self.value[0] + other.value[0], self.value[1] + other.value[1]) + + def __sub__(self, other): + return LRARational(self.value[0] - other.value[0], self.value[1] - other.value[1]) + + def __mul__(self, other): + assert not isinstance(other, LRARational) + return LRARational(self.value[0] * other, self.value[1] * other) + + def __getitem__(self, index): + return self.value[index] + + def __repr__(self): + return repr(self.value) + + +class LRAVariable(): + """ + Object to keep track of upper and lower bounds + on `self.var`. + """ + def __init__(self, var): + self.upper = LRARational(float("inf"), 0) + self.upper_from_eq = False + self.upper_from_neg = False + self.lower = LRARational(-float("inf"), 0) + self.lower_from_eq = False + self.lower_from_neg = False + self.assign = LRARational(0,0) + self.var = var + self.col_idx = None + + def __repr__(self): + return repr(self.var) + + def __eq__(self, other): + if not isinstance(other, LRAVariable): + return False + return other.var == self.var + + def __hash__(self): + return hash(self.var) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/minisat22_wrapper.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/minisat22_wrapper.py new file mode 100644 index 0000000000000000000000000000000000000000..1d5c1f8f14f04309f7cb8197cc05d01a3c108545 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/minisat22_wrapper.py @@ -0,0 +1,46 @@ +from sympy.assumptions.cnf import EncodedCNF + +def minisat22_satisfiable(expr, all_models=False, minimal=False): + + if not isinstance(expr, EncodedCNF): + exprs = EncodedCNF() + exprs.add_prop(expr) + expr = exprs + + from pysat.solvers import Minisat22 + + # Return UNSAT when False (encoded as 0) is present in the CNF + if {0} in expr.data: + if all_models: + return (f for f in [False]) + return False + + r = Minisat22(expr.data) + + if minimal: + r.set_phases([-(i+1) for i in range(r.nof_vars())]) + + if not r.solve(): + return False + + if not all_models: + return {expr.symbols[abs(lit) - 1]: lit > 0 for lit in r.get_model()} + + else: + # Make solutions SymPy compatible by creating a generator + def _gen(results): + satisfiable = False + while results.solve(): + sol = results.get_model() + yield {expr.symbols[abs(lit) - 1]: lit > 0 for lit in sol} + if minimal: + results.add_clause([-i for i in sol if i>0]) + else: + results.add_clause([-i for i in sol]) + satisfiable = True + if not satisfiable: + yield False + raise StopIteration + + + return _gen(r) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/pycosat_wrapper.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/pycosat_wrapper.py new file mode 100644 index 0000000000000000000000000000000000000000..5ff498b7e3f6b73d95e9b949598ef32df4ecf226 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/pycosat_wrapper.py @@ -0,0 +1,41 @@ +from sympy.assumptions.cnf import EncodedCNF + + +def pycosat_satisfiable(expr, all_models=False): + import pycosat + if not isinstance(expr, EncodedCNF): + exprs = EncodedCNF() + exprs.add_prop(expr) + expr = exprs + + # Return UNSAT when False (encoded as 0) is present in the CNF + if {0} in expr.data: + if all_models: + return (f for f in [False]) + return False + + if not all_models: + r = pycosat.solve(expr.data) + result = (r != "UNSAT") + if not result: + return result + return {expr.symbols[abs(lit) - 1]: lit > 0 for lit in r} + else: + r = pycosat.itersolve(expr.data) + result = (r != "UNSAT") + if not result: + return result + + # Make solutions SymPy compatible by creating a generator + def _gen(results): + satisfiable = False + try: + while True: + sol = next(results) + yield {expr.symbols[abs(lit) - 1]: lit > 0 for lit in sol} + satisfiable = True + except StopIteration: + if not satisfiable: + yield False + + return _gen(r) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/z3_wrapper.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/z3_wrapper.py new file mode 100644 index 0000000000000000000000000000000000000000..fe44f713a2edfd5286c0f81b737212146766b11b --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/algorithms/z3_wrapper.py @@ -0,0 +1,115 @@ +from sympy.printing.smtlib import smtlib_code +from sympy.assumptions.assume import AppliedPredicate +from sympy.assumptions.cnf import EncodedCNF +from sympy.assumptions.ask import Q + +from sympy.core import Add, Mul +from sympy.core.relational import Equality, LessThan, GreaterThan, StrictLessThan, StrictGreaterThan +from sympy.functions.elementary.complexes import Abs +from sympy.functions.elementary.exponential import Pow +from sympy.functions.elementary.miscellaneous import Min, Max +from sympy.logic.boolalg import And, Or, Xor, Implies +from sympy.logic.boolalg import Not, ITE +from sympy.assumptions.relation.equality import StrictGreaterThanPredicate, StrictLessThanPredicate, GreaterThanPredicate, LessThanPredicate, EqualityPredicate +from sympy.external import import_module + +def z3_satisfiable(expr, all_models=False): + if not isinstance(expr, EncodedCNF): + exprs = EncodedCNF() + exprs.add_prop(expr) + expr = exprs + + z3 = import_module("z3") + if z3 is None: + raise ImportError("z3 is not installed") + + s = encoded_cnf_to_z3_solver(expr, z3) + + res = str(s.check()) + if res == "unsat": + return False + elif res == "sat": + return z3_model_to_sympy_model(s.model(), expr) + else: + return None + + +def z3_model_to_sympy_model(z3_model, enc_cnf): + rev_enc = {value : key for key, value in enc_cnf.encoding.items()} + return {rev_enc[int(var.name()[1:])] : bool(z3_model[var]) for var in z3_model} + + +def clause_to_assertion(clause): + clause_strings = [f"d{abs(lit)}" if lit > 0 else f"(not d{abs(lit)})" for lit in clause] + return "(assert (or " + " ".join(clause_strings) + "))" + + +def encoded_cnf_to_z3_solver(enc_cnf, z3): + def dummify_bool(pred): + return False + assert isinstance(pred, AppliedPredicate) + + if pred.function in [Q.positive, Q.negative, Q.zero]: + return pred + else: + return False + + s = z3.Solver() + + declarations = [f"(declare-const d{var} Bool)" for var in enc_cnf.variables] + assertions = [clause_to_assertion(clause) for clause in enc_cnf.data] + + symbols = set() + for pred, enc in enc_cnf.encoding.items(): + if not isinstance(pred, AppliedPredicate): + continue + if pred.function not in (Q.gt, Q.lt, Q.ge, Q.le, Q.ne, Q.eq, Q.positive, Q.negative, Q.extended_negative, Q.extended_positive, Q.zero, Q.nonzero, Q.nonnegative, Q.nonpositive, Q.extended_nonzero, Q.extended_nonnegative, Q.extended_nonpositive): + continue + + pred_str = smtlib_code(pred, auto_declare=False, auto_assert=False, known_functions=known_functions) + + symbols |= pred.free_symbols + pred = pred_str + clause = f"(implies d{enc} {pred})" + assertion = "(assert " + clause + ")" + assertions.append(assertion) + + for sym in symbols: + declarations.append(f"(declare-const {sym} Real)") + + declarations = "\n".join(declarations) + assertions = "\n".join(assertions) + s.from_string(declarations) + s.from_string(assertions) + + return s + + +known_functions = { + Add: '+', + Mul: '*', + + Equality: '=', + LessThan: '<=', + GreaterThan: '>=', + StrictLessThan: '<', + StrictGreaterThan: '>', + + EqualityPredicate(): '=', + LessThanPredicate(): '<=', + GreaterThanPredicate(): '>=', + StrictLessThanPredicate(): '<', + StrictGreaterThanPredicate(): '>', + + Abs: 'abs', + Min: 'min', + Max: 'max', + Pow: '^', + + And: 'and', + Or: 'or', + Xor: 'xor', + Not: 'not', + ITE: 'ite', + Implies: '=>', + } diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/boolalg.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/boolalg.py new file mode 100644 index 0000000000000000000000000000000000000000..8e11a9b6361ac5d7e355d5d4fb176d8df443e07e --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/boolalg.py @@ -0,0 +1,3587 @@ +""" +Boolean algebra module for SymPy +""" + +from __future__ import annotations +from typing import TYPE_CHECKING, overload, Any +from collections.abc import Iterable, Mapping + +from collections import defaultdict +from itertools import chain, combinations, product, permutations +from sympy.core.add import Add +from sympy.core.basic import Basic +from sympy.core.cache import cacheit +from sympy.core.containers import Tuple +from sympy.core.decorators import sympify_method_args, sympify_return +from sympy.core.function import Application, Derivative +from sympy.core.kind import BooleanKind, NumberKind +from sympy.core.numbers import Number +from sympy.core.operations import LatticeOp +from sympy.core.singleton import Singleton, S +from sympy.core.sorting import ordered +from sympy.core.sympify import _sympy_converter, _sympify, sympify +from sympy.utilities.iterables import sift, ibin +from sympy.utilities.misc import filldedent + + +def as_Boolean(e): + """Like ``bool``, return the Boolean value of an expression, e, + which can be any instance of :py:class:`~.Boolean` or ``bool``. + + Examples + ======== + + >>> from sympy import true, false, nan + >>> from sympy.logic.boolalg import as_Boolean + >>> from sympy.abc import x + >>> as_Boolean(0) is false + True + >>> as_Boolean(1) is true + True + >>> as_Boolean(x) + x + >>> as_Boolean(2) + Traceback (most recent call last): + ... + TypeError: expecting bool or Boolean, not `2`. + >>> as_Boolean(nan) + Traceback (most recent call last): + ... + TypeError: expecting bool or Boolean, not `nan`. + + """ + from sympy.core.symbol import Symbol + if e == True: + return true + if e == False: + return false + if isinstance(e, Symbol): + z = e.is_zero + if z is None: + return e + return false if z else true + if isinstance(e, Boolean): + return e + raise TypeError('expecting bool or Boolean, not `%s`.' % e) + + +@sympify_method_args +class Boolean(Basic): + """A Boolean object is an object for which logic operations make sense.""" + + __slots__ = () + + kind = BooleanKind + + if TYPE_CHECKING: + + def __new__(cls, *args: Basic | complex) -> Boolean: + ... + + @overload # type: ignore + def subs(self, arg1: Mapping[Basic | complex, Boolean | complex], arg2: None=None) -> Boolean: ... + @overload + def subs(self, arg1: Iterable[tuple[Basic | complex, Boolean | complex]], arg2: None=None, **kwargs: Any) -> Boolean: ... + @overload + def subs(self, arg1: Boolean | complex, arg2: Boolean | complex) -> Boolean: ... + @overload + def subs(self, arg1: Mapping[Basic | complex, Basic | complex], arg2: None=None, **kwargs: Any) -> Basic: ... + @overload + def subs(self, arg1: Iterable[tuple[Basic | complex, Basic | complex]], arg2: None=None, **kwargs: Any) -> Basic: ... + @overload + def subs(self, arg1: Basic | complex, arg2: Basic | complex, **kwargs: Any) -> Basic: ... + + def subs(self, arg1: Mapping[Basic | complex, Basic | complex] | Basic | complex, # type: ignore + arg2: Basic | complex | None = None, **kwargs: Any) -> Basic: + ... + + def simplify(self, **kwargs) -> Boolean: + ... + + @sympify_return([('other', 'Boolean')], NotImplemented) + def __and__(self, other): + return And(self, other) + + __rand__ = __and__ + + @sympify_return([('other', 'Boolean')], NotImplemented) + def __or__(self, other): + return Or(self, other) + + __ror__ = __or__ + + def __invert__(self): + """Overloading for ~""" + return Not(self) + + @sympify_return([('other', 'Boolean')], NotImplemented) + def __rshift__(self, other): + return Implies(self, other) + + @sympify_return([('other', 'Boolean')], NotImplemented) + def __lshift__(self, other): + return Implies(other, self) + + __rrshift__ = __lshift__ + __rlshift__ = __rshift__ + + @sympify_return([('other', 'Boolean')], NotImplemented) + def __xor__(self, other): + return Xor(self, other) + + __rxor__ = __xor__ + + def equals(self, other): + """ + Returns ``True`` if the given formulas have the same truth table. + For two formulas to be equal they must have the same literals. + + Examples + ======== + + >>> from sympy.abc import A, B, C + >>> from sympy import And, Or, Not + >>> (A >> B).equals(~B >> ~A) + True + >>> Not(And(A, B, C)).equals(And(Not(A), Not(B), Not(C))) + False + >>> Not(And(A, Not(A))).equals(Or(B, Not(B))) + False + + """ + from sympy.logic.inference import satisfiable + from sympy.core.relational import Relational + + if self.has(Relational) or other.has(Relational): + raise NotImplementedError('handling of relationals') + return self.atoms() == other.atoms() and \ + not satisfiable(Not(Equivalent(self, other))) + + def to_nnf(self, simplify=True): + # override where necessary + return self + + def as_set(self): + """ + Rewrites Boolean expression in terms of real sets. + + Examples + ======== + + >>> from sympy import Symbol, Eq, Or, And + >>> x = Symbol('x', real=True) + >>> Eq(x, 0).as_set() + {0} + >>> (x > 0).as_set() + Interval.open(0, oo) + >>> And(-2 < x, x < 2).as_set() + Interval.open(-2, 2) + >>> Or(x < -2, 2 < x).as_set() + Union(Interval.open(-oo, -2), Interval.open(2, oo)) + + """ + from sympy.calculus.util import periodicity + from sympy.core.relational import Relational + + free = self.free_symbols + if len(free) == 1: + x = free.pop() + if x.kind is NumberKind: + reps = {} + for r in self.atoms(Relational): + if periodicity(r, x) not in (0, None): + s = r._eval_as_set() + if s in (S.EmptySet, S.UniversalSet, S.Reals): + reps[r] = s.as_relational(x) + continue + raise NotImplementedError(filldedent(''' + as_set is not implemented for relationals + with periodic solutions + ''')) + new = self.subs(reps) + if new.func != self.func: + return new.as_set() # restart with new obj + else: + return new._eval_as_set() + + return self._eval_as_set() + else: + raise NotImplementedError("Sorry, as_set has not yet been" + " implemented for multivariate" + " expressions") + + @property + def binary_symbols(self): + from sympy.core.relational import Eq, Ne + return set().union(*[i.binary_symbols for i in self.args + if i.is_Boolean or i.is_Symbol + or isinstance(i, (Eq, Ne))]) + + def _eval_refine(self, assumptions): + from sympy.assumptions import ask + ret = ask(self, assumptions) + if ret is True: + return true + elif ret is False: + return false + return None + + +class BooleanAtom(Boolean): + """ + Base class of :py:class:`~.BooleanTrue` and :py:class:`~.BooleanFalse`. + """ + is_Boolean = True + is_Atom = True + _op_priority = 11 # higher than Expr + + def simplify(self, *a, **kw): + return self + + def expand(self, *a, **kw): + return self + + @property + def canonical(self): + return self + + def _noop(self, other=None): + raise TypeError('BooleanAtom not allowed in this context.') + + __add__ = _noop + __radd__ = _noop + __sub__ = _noop + __rsub__ = _noop + __mul__ = _noop + __rmul__ = _noop + __pow__ = _noop + __rpow__ = _noop + __truediv__ = _noop + __rtruediv__ = _noop + __mod__ = _noop + __rmod__ = _noop + _eval_power = _noop + + def __lt__(self, other): + raise TypeError(filldedent(''' + A Boolean argument can only be used in + Eq and Ne; all other relationals expect + real expressions. + ''')) + + __le__ = __lt__ + __gt__ = __lt__ + __ge__ = __lt__ + # \\\ + + def _eval_simplify(self, **kwargs): + return self + + +class BooleanTrue(BooleanAtom, metaclass=Singleton): + """ + SymPy version of ``True``, a singleton that can be accessed via ``S.true``. + + This is the SymPy version of ``True``, for use in the logic module. The + primary advantage of using ``true`` instead of ``True`` is that shorthand Boolean + operations like ``~`` and ``>>`` will work as expected on this class, whereas with + True they act bitwise on 1. Functions in the logic module will return this + class when they evaluate to true. + + Notes + ===== + + There is liable to be some confusion as to when ``True`` should + be used and when ``S.true`` should be used in various contexts + throughout SymPy. An important thing to remember is that + ``sympify(True)`` returns ``S.true``. This means that for the most + part, you can just use ``True`` and it will automatically be converted + to ``S.true`` when necessary, similar to how you can generally use 1 + instead of ``S.One``. + + The rule of thumb is: + + "If the boolean in question can be replaced by an arbitrary symbolic + ``Boolean``, like ``Or(x, y)`` or ``x > 1``, use ``S.true``. + Otherwise, use ``True``" + + In other words, use ``S.true`` only on those contexts where the + boolean is being used as a symbolic representation of truth. + For example, if the object ends up in the ``.args`` of any expression, + then it must necessarily be ``S.true`` instead of ``True``, as + elements of ``.args`` must be ``Basic``. On the other hand, + ``==`` is not a symbolic operation in SymPy, since it always returns + ``True`` or ``False``, and does so in terms of structural equality + rather than mathematical, so it should return ``True``. The assumptions + system should use ``True`` and ``False``. Aside from not satisfying + the above rule of thumb, the assumptions system uses a three-valued logic + (``True``, ``False``, ``None``), whereas ``S.true`` and ``S.false`` + represent a two-valued logic. When in doubt, use ``True``. + + "``S.true == True is True``." + + While "``S.true is True``" is ``False``, "``S.true == True``" + is ``True``, so if there is any doubt over whether a function or + expression will return ``S.true`` or ``True``, just use ``==`` + instead of ``is`` to do the comparison, and it will work in either + case. Finally, for boolean flags, it's better to just use ``if x`` + instead of ``if x is True``. To quote PEP 8: + + Do not compare boolean values to ``True`` or ``False`` + using ``==``. + + * Yes: ``if greeting:`` + * No: ``if greeting == True:`` + * Worse: ``if greeting is True:`` + + Examples + ======== + + >>> from sympy import sympify, true, false, Or + >>> sympify(True) + True + >>> _ is True, _ is true + (False, True) + + >>> Or(true, false) + True + >>> _ is true + True + + Python operators give a boolean result for true but a + bitwise result for True + + >>> ~true, ~True # doctest: +SKIP + (False, -2) + >>> true >> true, True >> True + (True, 0) + + See Also + ======== + + sympy.logic.boolalg.BooleanFalse + + """ + def __bool__(self): + return True + + def __hash__(self): + return hash(True) + + def __eq__(self, other): + if other is True: + return True + if other is False: + return False + return super().__eq__(other) + + @property + def negated(self): + return false + + def as_set(self): + """ + Rewrite logic operators and relationals in terms of real sets. + + Examples + ======== + + >>> from sympy import true + >>> true.as_set() + UniversalSet + + """ + return S.UniversalSet + + +class BooleanFalse(BooleanAtom, metaclass=Singleton): + """ + SymPy version of ``False``, a singleton that can be accessed via ``S.false``. + + This is the SymPy version of ``False``, for use in the logic module. The + primary advantage of using ``false`` instead of ``False`` is that shorthand + Boolean operations like ``~`` and ``>>`` will work as expected on this class, + whereas with ``False`` they act bitwise on 0. Functions in the logic module + will return this class when they evaluate to false. + + Notes + ====== + + See the notes section in :py:class:`sympy.logic.boolalg.BooleanTrue` + + Examples + ======== + + >>> from sympy import sympify, true, false, Or + >>> sympify(False) + False + >>> _ is False, _ is false + (False, True) + + >>> Or(true, false) + True + >>> _ is true + True + + Python operators give a boolean result for false but a + bitwise result for False + + >>> ~false, ~False # doctest: +SKIP + (True, -1) + >>> false >> false, False >> False + (True, 0) + + See Also + ======== + + sympy.logic.boolalg.BooleanTrue + + """ + def __bool__(self): + return False + + def __hash__(self): + return hash(False) + + def __eq__(self, other): + if other is True: + return False + if other is False: + return True + return super().__eq__(other) + + @property + def negated(self): + return true + + def as_set(self): + """ + Rewrite logic operators and relationals in terms of real sets. + + Examples + ======== + + >>> from sympy import false + >>> false.as_set() + EmptySet + """ + return S.EmptySet + + +true = BooleanTrue() +false = BooleanFalse() +# We want S.true and S.false to work, rather than S.BooleanTrue and +# S.BooleanFalse, but making the class and instance names the same causes some +# major issues (like the inability to import the class directly from this +# file). +S.true = true +S.false = false + +_sympy_converter[bool] = lambda x: true if x else false + + +class BooleanFunction(Application, Boolean): + """Boolean function is a function that lives in a boolean space + It is used as base class for :py:class:`~.And`, :py:class:`~.Or`, + :py:class:`~.Not`, etc. + """ + is_Boolean = True + + def _eval_simplify(self, **kwargs): + rv = simplify_univariate(self) + if not isinstance(rv, BooleanFunction): + return rv.simplify(**kwargs) + rv = rv.func(*[a.simplify(**kwargs) for a in rv.args]) + return simplify_logic(rv) + + def simplify(self, **kwargs): + from sympy.simplify.simplify import simplify + return simplify(self, **kwargs) + + def __lt__(self, other): + raise TypeError(filldedent(''' + A Boolean argument can only be used in + Eq and Ne; all other relationals expect + real expressions. + ''')) + __le__ = __lt__ + __ge__ = __lt__ + __gt__ = __lt__ + + @classmethod + def binary_check_and_simplify(self, *args): + return [as_Boolean(i) for i in args] + + def to_nnf(self, simplify=True): + return self._to_nnf(*self.args, simplify=simplify) + + def to_anf(self, deep=True): + return self._to_anf(*self.args, deep=deep) + + @classmethod + def _to_nnf(cls, *args, **kwargs): + simplify = kwargs.get('simplify', True) + argset = set() + for arg in args: + if not is_literal(arg): + arg = arg.to_nnf(simplify) + if simplify: + if isinstance(arg, cls): + arg = arg.args + else: + arg = (arg,) + for a in arg: + if Not(a) in argset: + return cls.zero + argset.add(a) + else: + argset.add(arg) + return cls(*argset) + + @classmethod + def _to_anf(cls, *args, **kwargs): + deep = kwargs.get('deep', True) + new_args = [] + for arg in args: + if deep: + if not is_literal(arg) or isinstance(arg, Not): + arg = arg.to_anf(deep=deep) + new_args.append(arg) + return cls(*new_args, remove_true=False) + + # the diff method below is copied from Expr class + def diff(self, *symbols, **assumptions): + assumptions.setdefault("evaluate", True) + return Derivative(self, *symbols, **assumptions) + + def _eval_derivative(self, x): + if x in self.binary_symbols: + from sympy.core.relational import Eq + from sympy.functions.elementary.piecewise import Piecewise + return Piecewise( + (0, Eq(self.subs(x, 0), self.subs(x, 1))), + (1, True)) + elif x in self.free_symbols: + # not implemented, see https://www.encyclopediaofmath.org/ + # index.php/Boolean_differential_calculus + pass + else: + return S.Zero + + +class And(LatticeOp, BooleanFunction): + """ + Logical AND function. + + It evaluates its arguments in order, returning false immediately + when an argument is false and true if they are all true. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy import And + >>> x & y + x & y + + Notes + ===== + + The ``&`` operator is provided as a convenience, but note that its use + here is different from its normal use in Python, which is bitwise + and. Hence, ``And(a, b)`` and ``a & b`` will produce different results if + ``a`` and ``b`` are integers. + + >>> And(x, y).subs(x, 1) + y + + """ + zero = false + identity = true + + nargs = None + + if TYPE_CHECKING: + + def __new__(cls, *args: Boolean | bool) -> Boolean: # type: ignore + ... + + @property + def args(self) -> tuple[Boolean, ...]: + ... + + @classmethod + def _new_args_filter(cls, args): + args = BooleanFunction.binary_check_and_simplify(*args) + args = LatticeOp._new_args_filter(args, And) + newargs = [] + rel = set() + for x in ordered(args): + if x.is_Relational: + c = x.canonical + if c in rel: + continue + elif c.negated.canonical in rel: + return [false] + else: + rel.add(c) + newargs.append(x) + return newargs + + def _eval_subs(self, old, new): + args = [] + bad = None + for i in self.args: + try: + i = i.subs(old, new) + except TypeError: + # store TypeError + if bad is None: + bad = i + continue + if i == False: + return false + elif i != True: + args.append(i) + if bad is not None: + # let it raise + bad.subs(old, new) + # If old is And, replace the parts of the arguments with new if all + # are there + if isinstance(old, And): + old_set = set(old.args) + if old_set.issubset(args): + args = set(args) - old_set + args.add(new) + + return self.func(*args) + + def _eval_simplify(self, **kwargs): + from sympy.core.relational import Equality, Relational + from sympy.solvers.solveset import linear_coeffs + # standard simplify + rv = super()._eval_simplify(**kwargs) + if not isinstance(rv, And): + return rv + + # simplify args that are equalities involving + # symbols so x == 0 & x == y -> x==0 & y == 0 + Rel, nonRel = sift(rv.args, lambda i: isinstance(i, Relational), + binary=True) + if not Rel: + return rv + eqs, other = sift(Rel, lambda i: isinstance(i, Equality), binary=True) + + measure = kwargs['measure'] + if eqs: + ratio = kwargs['ratio'] + reps = {} + sifted = {} + # group by length of free symbols + sifted = sift(ordered([ + (i.free_symbols, i) for i in eqs]), + lambda x: len(x[0])) + eqs = [] + nonlineqs = [] + while 1 in sifted: + for free, e in sifted.pop(1): + x = free.pop() + if (e.lhs != x or x in e.rhs.free_symbols) and x not in reps: + try: + m, b = linear_coeffs( + Add(e.lhs, -e.rhs, evaluate=False), x) + enew = e.func(x, -b/m) + if measure(enew) <= ratio*measure(e): + e = enew + else: + eqs.append(e) + continue + except ValueError: + pass + if x in reps: + eqs.append(e.subs(x, reps[x])) + elif e.lhs == x and x not in e.rhs.free_symbols: + reps[x] = e.rhs + eqs.append(e) + else: + # x is not yet identified, but may be later + nonlineqs.append(e) + resifted = defaultdict(list) + for k in sifted: + for f, e in sifted[k]: + e = e.xreplace(reps) + f = e.free_symbols + resifted[len(f)].append((f, e)) + sifted = resifted + for k in sifted: + eqs.extend([e for f, e in sifted[k]]) + nonlineqs = [ei.subs(reps) for ei in nonlineqs] + other = [ei.subs(reps) for ei in other] + rv = rv.func(*([i.canonical for i in (eqs + nonlineqs + other)] + nonRel)) + patterns = _simplify_patterns_and() + threeterm_patterns = _simplify_patterns_and3() + return _apply_patternbased_simplification(rv, patterns, + measure, false, + threeterm_patterns=threeterm_patterns) + + def _eval_as_set(self): + from sympy.sets.sets import Intersection + return Intersection(*[arg.as_set() for arg in self.args]) + + def _eval_rewrite_as_Nor(self, *args, **kwargs): + return Nor(*[Not(arg) for arg in self.args]) + + def to_anf(self, deep=True): + if deep: + result = And._to_anf(*self.args, deep=deep) + return distribute_xor_over_and(result) + return self + + +class Or(LatticeOp, BooleanFunction): + """ + Logical OR function + + It evaluates its arguments in order, returning true immediately + when an argument is true, and false if they are all false. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy import Or + >>> x | y + x | y + + Notes + ===== + + The ``|`` operator is provided as a convenience, but note that its use + here is different from its normal use in Python, which is bitwise + or. Hence, ``Or(a, b)`` and ``a | b`` will return different things if + ``a`` and ``b`` are integers. + + >>> Or(x, y).subs(x, 0) + y + + """ + zero = true + identity = false + + if TYPE_CHECKING: + + def __new__(cls, *args: Boolean | bool) -> Boolean: # type: ignore + ... + + @property + def args(self) -> tuple[Boolean, ...]: + ... + + @classmethod + def _new_args_filter(cls, args): + newargs = [] + rel = [] + args = BooleanFunction.binary_check_and_simplify(*args) + for x in args: + if x.is_Relational: + c = x.canonical + if c in rel: + continue + nc = c.negated.canonical + if any(r == nc for r in rel): + return [true] + rel.append(c) + newargs.append(x) + return LatticeOp._new_args_filter(newargs, Or) + + def _eval_subs(self, old, new): + args = [] + bad = None + for i in self.args: + try: + i = i.subs(old, new) + except TypeError: + # store TypeError + if bad is None: + bad = i + continue + if i == True: + return true + elif i != False: + args.append(i) + if bad is not None: + # let it raise + bad.subs(old, new) + # If old is Or, replace the parts of the arguments with new if all + # are there + if isinstance(old, Or): + old_set = set(old.args) + if old_set.issubset(args): + args = set(args) - old_set + args.add(new) + + return self.func(*args) + + def _eval_as_set(self): + from sympy.sets.sets import Union + return Union(*[arg.as_set() for arg in self.args]) + + def _eval_rewrite_as_Nand(self, *args, **kwargs): + return Nand(*[Not(arg) for arg in self.args]) + + def _eval_simplify(self, **kwargs): + from sympy.core.relational import Le, Ge, Eq + lege = self.atoms(Le, Ge) + if lege: + reps = {i: self.func( + Eq(i.lhs, i.rhs), i.strict) for i in lege} + return self.xreplace(reps)._eval_simplify(**kwargs) + # standard simplify + rv = super()._eval_simplify(**kwargs) + if not isinstance(rv, Or): + return rv + patterns = _simplify_patterns_or() + return _apply_patternbased_simplification(rv, patterns, + kwargs['measure'], true) + + def to_anf(self, deep=True): + args = range(1, len(self.args) + 1) + args = (combinations(self.args, j) for j in args) + args = chain.from_iterable(args) # powerset + args = (And(*arg) for arg in args) + args = (to_anf(x, deep=deep) if deep else x for x in args) + return Xor(*list(args), remove_true=False) + + +class Not(BooleanFunction): + """ + Logical Not function (negation) + + + Returns ``true`` if the statement is ``false`` or ``False``. + Returns ``false`` if the statement is ``true`` or ``True``. + + Examples + ======== + + >>> from sympy import Not, And, Or + >>> from sympy.abc import x, A, B + >>> Not(True) + False + >>> Not(False) + True + >>> Not(And(True, False)) + True + >>> Not(Or(True, False)) + False + >>> Not(And(And(True, x), Or(x, False))) + ~x + >>> ~x + ~x + >>> Not(And(Or(A, B), Or(~A, ~B))) + ~((A | B) & (~A | ~B)) + + Notes + ===== + + - The ``~`` operator is provided as a convenience, but note that its use + here is different from its normal use in Python, which is bitwise + not. In particular, ``~a`` and ``Not(a)`` will be different if ``a`` is + an integer. Furthermore, since bools in Python subclass from ``int``, + ``~True`` is the same as ``~1`` which is ``-2``, which has a boolean + value of True. To avoid this issue, use the SymPy boolean types + ``true`` and ``false``. + + - As of Python 3.12, the bitwise not operator ``~`` used on a + Python ``bool`` is deprecated and will emit a warning. + + >>> from sympy import true + >>> ~True # doctest: +SKIP + -2 + >>> ~true + False + + """ + + is_Not = True + + @classmethod + def eval(cls, arg): + if isinstance(arg, Number) or arg in (True, False): + return false if arg else true + if arg.is_Not: + return arg.args[0] + # Simplify Relational objects. + if arg.is_Relational: + return arg.negated + + def _eval_as_set(self): + """ + Rewrite logic operators and relationals in terms of real sets. + + Examples + ======== + + >>> from sympy import Not, Symbol + >>> x = Symbol('x') + >>> Not(x > 0).as_set() + Interval(-oo, 0) + """ + return self.args[0].as_set().complement(S.Reals) + + def to_nnf(self, simplify=True): + if is_literal(self): + return self + + expr = self.args[0] + + func, args = expr.func, expr.args + + if func == And: + return Or._to_nnf(*[Not(arg) for arg in args], simplify=simplify) + + if func == Or: + return And._to_nnf(*[Not(arg) for arg in args], simplify=simplify) + + if func == Implies: + a, b = args + return And._to_nnf(a, Not(b), simplify=simplify) + + if func == Equivalent: + return And._to_nnf(Or(*args), Or(*[Not(arg) for arg in args]), + simplify=simplify) + + if func == Xor: + result = [] + for i in range(1, len(args)+1, 2): + for neg in combinations(args, i): + clause = [Not(s) if s in neg else s for s in args] + result.append(Or(*clause)) + return And._to_nnf(*result, simplify=simplify) + + if func == ITE: + a, b, c = args + return And._to_nnf(Or(a, Not(c)), Or(Not(a), Not(b)), simplify=simplify) + + raise ValueError("Illegal operator %s in expression" % func) + + def to_anf(self, deep=True): + return Xor._to_anf(true, self.args[0], deep=deep) + + +class Xor(BooleanFunction): + """ + Logical XOR (exclusive OR) function. + + + Returns True if an odd number of the arguments are True and the rest are + False. + + Returns False if an even number of the arguments are True and the rest are + False. + + Examples + ======== + + >>> from sympy.logic.boolalg import Xor + >>> from sympy import symbols + >>> x, y = symbols('x y') + >>> Xor(True, False) + True + >>> Xor(True, True) + False + >>> Xor(True, False, True, True, False) + True + >>> Xor(True, False, True, False) + False + >>> x ^ y + x ^ y + + Notes + ===== + + The ``^`` operator is provided as a convenience, but note that its use + here is different from its normal use in Python, which is bitwise xor. In + particular, ``a ^ b`` and ``Xor(a, b)`` will be different if ``a`` and + ``b`` are integers. + + >>> Xor(x, y).subs(y, 0) + x + + """ + def __new__(cls, *args, remove_true=True, **kwargs): + argset = set() + obj = super().__new__(cls, *args, **kwargs) + for arg in obj._args: + if isinstance(arg, Number) or arg in (True, False): + if arg: + arg = true + else: + continue + if isinstance(arg, Xor): + for a in arg.args: + argset.remove(a) if a in argset else argset.add(a) + elif arg in argset: + argset.remove(arg) + else: + argset.add(arg) + rel = [(r, r.canonical, r.negated.canonical) + for r in argset if r.is_Relational] + odd = False # is number of complimentary pairs odd? start 0 -> False + remove = [] + for i, (r, c, nc) in enumerate(rel): + for j in range(i + 1, len(rel)): + rj, cj = rel[j][:2] + if cj == nc: + odd = not odd + break + elif cj == c: + break + else: + continue + remove.append((r, rj)) + if odd: + argset.remove(true) if true in argset else argset.add(true) + for a, b in remove: + argset.remove(a) + argset.remove(b) + if len(argset) == 0: + return false + elif len(argset) == 1: + return argset.pop() + elif True in argset and remove_true: + argset.remove(True) + return Not(Xor(*argset)) + else: + obj._args = tuple(ordered(argset)) + obj._argset = frozenset(argset) + return obj + + # XXX: This should be cached on the object rather than using cacheit + # Maybe it can be computed in __new__? + @property # type: ignore + @cacheit + def args(self): + return tuple(ordered(self._argset)) + + def to_nnf(self, simplify=True): + args = [] + for i in range(0, len(self.args)+1, 2): + for neg in combinations(self.args, i): + clause = [Not(s) if s in neg else s for s in self.args] + args.append(Or(*clause)) + return And._to_nnf(*args, simplify=simplify) + + def _eval_rewrite_as_Or(self, *args, **kwargs): + a = self.args + return Or(*[_convert_to_varsSOP(x, self.args) + for x in _get_odd_parity_terms(len(a))]) + + def _eval_rewrite_as_And(self, *args, **kwargs): + a = self.args + return And(*[_convert_to_varsPOS(x, self.args) + for x in _get_even_parity_terms(len(a))]) + + def _eval_simplify(self, **kwargs): + # as standard simplify uses simplify_logic which writes things as + # And and Or, we only simplify the partial expressions before using + # patterns + rv = self.func(*[a.simplify(**kwargs) for a in self.args]) + rv = rv.to_anf() + if not isinstance(rv, Xor): # This shouldn't really happen here + return rv + patterns = _simplify_patterns_xor() + return _apply_patternbased_simplification(rv, patterns, + kwargs['measure'], None) + + def _eval_subs(self, old, new): + # If old is Xor, replace the parts of the arguments with new if all + # are there + if isinstance(old, Xor): + old_set = set(old.args) + if old_set.issubset(self.args): + args = set(self.args) - old_set + args.add(new) + return self.func(*args) + + +class Nand(BooleanFunction): + """ + Logical NAND function. + + It evaluates its arguments in order, giving True immediately if any + of them are False, and False if they are all True. + + Returns True if any of the arguments are False + Returns False if all arguments are True + + Examples + ======== + + >>> from sympy.logic.boolalg import Nand + >>> from sympy import symbols + >>> x, y = symbols('x y') + >>> Nand(False, True) + True + >>> Nand(True, True) + False + >>> Nand(x, y) + ~(x & y) + + """ + @classmethod + def eval(cls, *args): + return Not(And(*args)) + + +class Nor(BooleanFunction): + """ + Logical NOR function. + + It evaluates its arguments in order, giving False immediately if any + of them are True, and True if they are all False. + + Returns False if any argument is True + Returns True if all arguments are False + + Examples + ======== + + >>> from sympy.logic.boolalg import Nor + >>> from sympy import symbols + >>> x, y = symbols('x y') + + >>> Nor(True, False) + False + >>> Nor(True, True) + False + >>> Nor(False, True) + False + >>> Nor(False, False) + True + >>> Nor(x, y) + ~(x | y) + + """ + @classmethod + def eval(cls, *args): + return Not(Or(*args)) + + +class Xnor(BooleanFunction): + """ + Logical XNOR function. + + Returns False if an odd number of the arguments are True and the rest are + False. + + Returns True if an even number of the arguments are True and the rest are + False. + + Examples + ======== + + >>> from sympy.logic.boolalg import Xnor + >>> from sympy import symbols + >>> x, y = symbols('x y') + >>> Xnor(True, False) + False + >>> Xnor(True, True) + True + >>> Xnor(True, False, True, True, False) + False + >>> Xnor(True, False, True, False) + True + + """ + @classmethod + def eval(cls, *args): + return Not(Xor(*args)) + + +class Implies(BooleanFunction): + r""" + Logical implication. + + A implies B is equivalent to if A then B. Mathematically, it is written + as `A \Rightarrow B` and is equivalent to `\neg A \vee B` or ``~A | B``. + + Accepts two Boolean arguments; A and B. + Returns False if A is True and B is False + Returns True otherwise. + + Examples + ======== + + >>> from sympy.logic.boolalg import Implies + >>> from sympy import symbols + >>> x, y = symbols('x y') + + >>> Implies(True, False) + False + >>> Implies(False, False) + True + >>> Implies(True, True) + True + >>> Implies(False, True) + True + >>> x >> y + Implies(x, y) + >>> y << x + Implies(x, y) + + Notes + ===== + + The ``>>`` and ``<<`` operators are provided as a convenience, but note + that their use here is different from their normal use in Python, which is + bit shifts. Hence, ``Implies(a, b)`` and ``a >> b`` will return different + things if ``a`` and ``b`` are integers. In particular, since Python + considers ``True`` and ``False`` to be integers, ``True >> True`` will be + the same as ``1 >> 1``, i.e., 0, which has a truth value of False. To + avoid this issue, use the SymPy objects ``true`` and ``false``. + + >>> from sympy import true, false + >>> True >> False + 1 + >>> true >> false + False + + """ + @classmethod + def eval(cls, *args): + try: + newargs = [] + for x in args: + if isinstance(x, Number) or x in (0, 1): + newargs.append(bool(x)) + else: + newargs.append(x) + A, B = newargs + except ValueError: + raise ValueError( + "%d operand(s) used for an Implies " + "(pairs are required): %s" % (len(args), str(args))) + if A in (True, False) or B in (True, False): + return Or(Not(A), B) + elif A == B: + return true + elif A.is_Relational and B.is_Relational: + if A.canonical == B.canonical: + return true + if A.negated.canonical == B.canonical: + return B + else: + return Basic.__new__(cls, *args) + + def to_nnf(self, simplify=True): + a, b = self.args + return Or._to_nnf(Not(a), b, simplify=simplify) + + def to_anf(self, deep=True): + a, b = self.args + return Xor._to_anf(true, a, And(a, b), deep=deep) + + +class Equivalent(BooleanFunction): + """ + Equivalence relation. + + ``Equivalent(A, B)`` is True iff A and B are both True or both False. + + Returns True if all of the arguments are logically equivalent. + Returns False otherwise. + + For two arguments, this is equivalent to :py:class:`~.Xnor`. + + Examples + ======== + + >>> from sympy.logic.boolalg import Equivalent, And + >>> from sympy.abc import x + >>> Equivalent(False, False, False) + True + >>> Equivalent(True, False, False) + False + >>> Equivalent(x, And(x, True)) + True + + """ + def __new__(cls, *args, **options): + from sympy.core.relational import Relational + args = [_sympify(arg) for arg in args] + + argset = set(args) + for x in args: + if isinstance(x, Number) or x in [True, False]: # Includes 0, 1 + argset.discard(x) + argset.add(bool(x)) + rel = [] + for r in argset: + if isinstance(r, Relational): + rel.append((r, r.canonical, r.negated.canonical)) + remove = [] + for i, (r, c, nc) in enumerate(rel): + for j in range(i + 1, len(rel)): + rj, cj = rel[j][:2] + if cj == nc: + return false + elif cj == c: + remove.append((r, rj)) + break + for a, b in remove: + argset.remove(a) + argset.remove(b) + argset.add(True) + if len(argset) <= 1: + return true + if True in argset: + argset.discard(True) + return And(*argset) + if False in argset: + argset.discard(False) + return And(*[Not(arg) for arg in argset]) + _args = frozenset(argset) + obj = super().__new__(cls, _args) + obj._argset = _args + return obj + + # XXX: This should be cached on the object rather than using cacheit + # Maybe it can be computed in __new__? + @property # type: ignore + @cacheit + def args(self): + return tuple(ordered(self._argset)) + + def to_nnf(self, simplify=True): + args = [] + for a, b in zip(self.args, self.args[1:]): + args.append(Or(Not(a), b)) + args.append(Or(Not(self.args[-1]), self.args[0])) + return And._to_nnf(*args, simplify=simplify) + + def to_anf(self, deep=True): + a = And(*self.args) + b = And(*[to_anf(Not(arg), deep=False) for arg in self.args]) + b = distribute_xor_over_and(b) + return Xor._to_anf(a, b, deep=deep) + + +class ITE(BooleanFunction): + """ + If-then-else clause. + + ``ITE(A, B, C)`` evaluates and returns the result of B if A is true + else it returns the result of C. All args must be Booleans. + + From a logic gate perspective, ITE corresponds to a 2-to-1 multiplexer, + where A is the select signal. + + Examples + ======== + + >>> from sympy.logic.boolalg import ITE, And, Xor, Or + >>> from sympy.abc import x, y, z + >>> ITE(True, False, True) + False + >>> ITE(Or(True, False), And(True, True), Xor(True, True)) + True + >>> ITE(x, y, z) + ITE(x, y, z) + >>> ITE(True, x, y) + x + >>> ITE(False, x, y) + y + >>> ITE(x, y, y) + y + + Trying to use non-Boolean args will generate a TypeError: + + >>> ITE(True, [], ()) + Traceback (most recent call last): + ... + TypeError: expecting bool, Boolean or ITE, not `[]` + + """ + def __new__(cls, *args, **kwargs): + from sympy.core.relational import Eq, Ne + if len(args) != 3: + raise ValueError('expecting exactly 3 args') + a, b, c = args + # check use of binary symbols + if isinstance(a, (Eq, Ne)): + # in this context, we can evaluate the Eq/Ne + # if one arg is a binary symbol and the other + # is true/false + b, c = map(as_Boolean, (b, c)) + bin_syms = set().union(*[i.binary_symbols for i in (b, c)]) + if len(set(a.args) - bin_syms) == 1: + # one arg is a binary_symbols + _a = a + if a.lhs is true: + a = a.rhs + elif a.rhs is true: + a = a.lhs + elif a.lhs is false: + a = Not(a.rhs) + elif a.rhs is false: + a = Not(a.lhs) + else: + # binary can only equal True or False + a = false + if isinstance(_a, Ne): + a = Not(a) + else: + a, b, c = BooleanFunction.binary_check_and_simplify( + a, b, c) + rv = None + if kwargs.get('evaluate', True): + rv = cls.eval(a, b, c) + if rv is None: + rv = BooleanFunction.__new__(cls, a, b, c, evaluate=False) + return rv + + @classmethod + def eval(cls, *args): + from sympy.core.relational import Eq, Ne + # do the args give a singular result? + a, b, c = args + if isinstance(a, (Ne, Eq)): + _a = a + if true in a.args: + a = a.lhs if a.rhs is true else a.rhs + elif false in a.args: + a = Not(a.lhs) if a.rhs is false else Not(a.rhs) + else: + _a = None + if _a is not None and isinstance(_a, Ne): + a = Not(a) + if a is true: + return b + if a is false: + return c + if b == c: + return b + else: + # or maybe the results allow the answer to be expressed + # in terms of the condition + if b is true and c is false: + return a + if b is false and c is true: + return Not(a) + if [a, b, c] != args: + return cls(a, b, c, evaluate=False) + + def to_nnf(self, simplify=True): + a, b, c = self.args + return And._to_nnf(Or(Not(a), b), Or(a, c), simplify=simplify) + + def _eval_as_set(self): + return self.to_nnf().as_set() + + def _eval_rewrite_as_Piecewise(self, *args, **kwargs): + from sympy.functions.elementary.piecewise import Piecewise + return Piecewise((args[1], args[0]), (args[2], True)) + + +class Exclusive(BooleanFunction): + """ + True if only one or no argument is true. + + ``Exclusive(A, B, C)`` is equivalent to ``~(A & B) & ~(A & C) & ~(B & C)``. + + For two arguments, this is equivalent to :py:class:`~.Xor`. + + Examples + ======== + + >>> from sympy.logic.boolalg import Exclusive + >>> Exclusive(False, False, False) + True + >>> Exclusive(False, True, False) + True + >>> Exclusive(False, True, True) + False + + """ + @classmethod + def eval(cls, *args): + and_args = [] + for a, b in combinations(args, 2): + and_args.append(Not(And(a, b))) + return And(*and_args) + + +# end class definitions. Some useful methods + + +def conjuncts(expr): + """Return a list of the conjuncts in ``expr``. + + Examples + ======== + + >>> from sympy.logic.boolalg import conjuncts + >>> from sympy.abc import A, B + >>> conjuncts(A & B) + frozenset({A, B}) + >>> conjuncts(A | B) + frozenset({A | B}) + + """ + return And.make_args(expr) + + +def disjuncts(expr): + """Return a list of the disjuncts in ``expr``. + + Examples + ======== + + >>> from sympy.logic.boolalg import disjuncts + >>> from sympy.abc import A, B + >>> disjuncts(A | B) + frozenset({A, B}) + >>> disjuncts(A & B) + frozenset({A & B}) + + """ + return Or.make_args(expr) + + +def distribute_and_over_or(expr): + """ + Given a sentence ``expr`` consisting of conjunctions and disjunctions + of literals, return an equivalent sentence in CNF. + + Examples + ======== + + >>> from sympy.logic.boolalg import distribute_and_over_or, And, Or, Not + >>> from sympy.abc import A, B, C + >>> distribute_and_over_or(Or(A, And(Not(B), Not(C)))) + (A | ~B) & (A | ~C) + + """ + return _distribute((expr, And, Or)) + + +def distribute_or_over_and(expr): + """ + Given a sentence ``expr`` consisting of conjunctions and disjunctions + of literals, return an equivalent sentence in DNF. + + Note that the output is NOT simplified. + + Examples + ======== + + >>> from sympy.logic.boolalg import distribute_or_over_and, And, Or, Not + >>> from sympy.abc import A, B, C + >>> distribute_or_over_and(And(Or(Not(A), B), C)) + (B & C) | (C & ~A) + + """ + return _distribute((expr, Or, And)) + + +def distribute_xor_over_and(expr): + """ + Given a sentence ``expr`` consisting of conjunction and + exclusive disjunctions of literals, return an + equivalent exclusive disjunction. + + Note that the output is NOT simplified. + + Examples + ======== + + >>> from sympy.logic.boolalg import distribute_xor_over_and, And, Xor, Not + >>> from sympy.abc import A, B, C + >>> distribute_xor_over_and(And(Xor(Not(A), B), C)) + (B & C) ^ (C & ~A) + """ + return _distribute((expr, Xor, And)) + + +def _distribute(info): + """ + Distributes ``info[1]`` over ``info[2]`` with respect to ``info[0]``. + """ + if isinstance(info[0], info[2]): + for arg in info[0].args: + if isinstance(arg, info[1]): + conj = arg + break + else: + return info[0] + rest = info[2](*[a for a in info[0].args if a is not conj]) + return info[1](*list(map(_distribute, + [(info[2](c, rest), info[1], info[2]) + for c in conj.args])), remove_true=False) + elif isinstance(info[0], info[1]): + return info[1](*list(map(_distribute, + [(x, info[1], info[2]) + for x in info[0].args])), + remove_true=False) + else: + return info[0] + + +def to_anf(expr, deep=True): + r""" + Converts expr to Algebraic Normal Form (ANF). + + ANF is a canonical normal form, which means that two + equivalent formulas will convert to the same ANF. + + A logical expression is in ANF if it has the form + + .. math:: 1 \oplus a \oplus b \oplus ab \oplus abc + + i.e. it can be: + - purely true, + - purely false, + - conjunction of variables, + - exclusive disjunction. + + The exclusive disjunction can only contain true, variables + or conjunction of variables. No negations are permitted. + + If ``deep`` is ``False``, arguments of the boolean + expression are considered variables, i.e. only the + top-level expression is converted to ANF. + + Examples + ======== + >>> from sympy.logic.boolalg import And, Or, Not, Implies, Equivalent + >>> from sympy.logic.boolalg import to_anf + >>> from sympy.abc import A, B, C + >>> to_anf(Not(A)) + A ^ True + >>> to_anf(And(Or(A, B), Not(C))) + A ^ B ^ (A & B) ^ (A & C) ^ (B & C) ^ (A & B & C) + >>> to_anf(Implies(Not(A), Equivalent(B, C)), deep=False) + True ^ ~A ^ (~A & (Equivalent(B, C))) + + """ + expr = sympify(expr) + + if is_anf(expr): + return expr + return expr.to_anf(deep=deep) + + +def to_nnf(expr, simplify=True): + """ + Converts ``expr`` to Negation Normal Form (NNF). + + A logical expression is in NNF if it + contains only :py:class:`~.And`, :py:class:`~.Or` and :py:class:`~.Not`, + and :py:class:`~.Not` is applied only to literals. + If ``simplify`` is ``True``, the result contains no redundant clauses. + + Examples + ======== + + >>> from sympy.abc import A, B, C, D + >>> from sympy.logic.boolalg import Not, Equivalent, to_nnf + >>> to_nnf(Not((~A & ~B) | (C & D))) + (A | B) & (~C | ~D) + >>> to_nnf(Equivalent(A >> B, B >> A)) + (A | ~B | (A & ~B)) & (B | ~A | (B & ~A)) + + """ + if is_nnf(expr, simplify): + return expr + return expr.to_nnf(simplify) + + +def to_cnf(expr, simplify=False, force=False): + """ + Convert a propositional logical sentence ``expr`` to conjunctive normal + form: ``((A | ~B | ...) & (B | C | ...) & ...)``. + If ``simplify`` is ``True``, ``expr`` is evaluated to its simplest CNF + form using the Quine-McCluskey algorithm; this may take a long + time. If there are more than 8 variables the ``force`` flag must be set + to ``True`` to simplify (default is ``False``). + + Examples + ======== + + >>> from sympy.logic.boolalg import to_cnf + >>> from sympy.abc import A, B, D + >>> to_cnf(~(A | B) | D) + (D | ~A) & (D | ~B) + >>> to_cnf((A | B) & (A | ~A), True) + A | B + + """ + expr = sympify(expr) + if not isinstance(expr, BooleanFunction): + return expr + + if simplify: + if not force and len(_find_predicates(expr)) > 8: + raise ValueError(filldedent(''' + To simplify a logical expression with more + than 8 variables may take a long time and requires + the use of `force=True`.''')) + return simplify_logic(expr, 'cnf', True, force=force) + + # Don't convert unless we have to + if is_cnf(expr): + return expr + + expr = eliminate_implications(expr) + res = distribute_and_over_or(expr) + + return res + + +def to_dnf(expr, simplify=False, force=False): + """ + Convert a propositional logical sentence ``expr`` to disjunctive normal + form: ``((A & ~B & ...) | (B & C & ...) | ...)``. + If ``simplify`` is ``True``, ``expr`` is evaluated to its simplest DNF form using + the Quine-McCluskey algorithm; this may take a long + time. If there are more than 8 variables, the ``force`` flag must be set to + ``True`` to simplify (default is ``False``). + + Examples + ======== + + >>> from sympy.logic.boolalg import to_dnf + >>> from sympy.abc import A, B, C + >>> to_dnf(B & (A | C)) + (A & B) | (B & C) + >>> to_dnf((A & B) | (A & ~B) | (B & C) | (~B & C), True) + A | C + + """ + expr = sympify(expr) + if not isinstance(expr, BooleanFunction): + return expr + + if simplify: + if not force and len(_find_predicates(expr)) > 8: + raise ValueError(filldedent(''' + To simplify a logical expression with more + than 8 variables may take a long time and requires + the use of `force=True`.''')) + return simplify_logic(expr, 'dnf', True, force=force) + + # Don't convert unless we have to + if is_dnf(expr): + return expr + + expr = eliminate_implications(expr) + return distribute_or_over_and(expr) + + +def is_anf(expr): + r""" + Checks if ``expr`` is in Algebraic Normal Form (ANF). + + A logical expression is in ANF if it has the form + + .. math:: 1 \oplus a \oplus b \oplus ab \oplus abc + + i.e. it is purely true, purely false, conjunction of + variables or exclusive disjunction. The exclusive + disjunction can only contain true, variables or + conjunction of variables. No negations are permitted. + + Examples + ======== + + >>> from sympy.logic.boolalg import And, Not, Xor, true, is_anf + >>> from sympy.abc import A, B, C + >>> is_anf(true) + True + >>> is_anf(A) + True + >>> is_anf(And(A, B, C)) + True + >>> is_anf(Xor(A, Not(B))) + False + + """ + expr = sympify(expr) + + if is_literal(expr) and not isinstance(expr, Not): + return True + + if isinstance(expr, And): + for arg in expr.args: + if not arg.is_Symbol: + return False + return True + + elif isinstance(expr, Xor): + for arg in expr.args: + if isinstance(arg, And): + for a in arg.args: + if not a.is_Symbol: + return False + elif is_literal(arg): + if isinstance(arg, Not): + return False + else: + return False + return True + + else: + return False + + +def is_nnf(expr, simplified=True): + """ + Checks if ``expr`` is in Negation Normal Form (NNF). + + A logical expression is in NNF if it + contains only :py:class:`~.And`, :py:class:`~.Or` and :py:class:`~.Not`, + and :py:class:`~.Not` is applied only to literals. + If ``simplified`` is ``True``, checks if result contains no redundant clauses. + + Examples + ======== + + >>> from sympy.abc import A, B, C + >>> from sympy.logic.boolalg import Not, is_nnf + >>> is_nnf(A & B | ~C) + True + >>> is_nnf((A | ~A) & (B | C)) + False + >>> is_nnf((A | ~A) & (B | C), False) + True + >>> is_nnf(Not(A & B) | C) + False + >>> is_nnf((A >> B) & (B >> A)) + False + + """ + + expr = sympify(expr) + if is_literal(expr): + return True + + stack = [expr] + + while stack: + expr = stack.pop() + if expr.func in (And, Or): + if simplified: + args = expr.args + for arg in args: + if Not(arg) in args: + return False + stack.extend(expr.args) + + elif not is_literal(expr): + return False + + return True + + +def is_cnf(expr): + """ + Test whether or not an expression is in conjunctive normal form. + + Examples + ======== + + >>> from sympy.logic.boolalg import is_cnf + >>> from sympy.abc import A, B, C + >>> is_cnf(A | B | C) + True + >>> is_cnf(A & B & C) + True + >>> is_cnf((A & B) | C) + False + + """ + return _is_form(expr, And, Or) + + +def is_dnf(expr): + """ + Test whether or not an expression is in disjunctive normal form. + + Examples + ======== + + >>> from sympy.logic.boolalg import is_dnf + >>> from sympy.abc import A, B, C + >>> is_dnf(A | B | C) + True + >>> is_dnf(A & B & C) + True + >>> is_dnf((A & B) | C) + True + >>> is_dnf(A & (B | C)) + False + + """ + return _is_form(expr, Or, And) + + +def _is_form(expr, function1, function2): + """ + Test whether or not an expression is of the required form. + + """ + expr = sympify(expr) + + vals = function1.make_args(expr) if isinstance(expr, function1) else [expr] + for lit in vals: + if isinstance(lit, function2): + vals2 = function2.make_args(lit) if isinstance(lit, function2) else [lit] + for l in vals2: + if is_literal(l) is False: + return False + elif is_literal(lit) is False: + return False + + return True + + +def eliminate_implications(expr): + """ + Change :py:class:`~.Implies` and :py:class:`~.Equivalent` into + :py:class:`~.And`, :py:class:`~.Or`, and :py:class:`~.Not`. + That is, return an expression that is equivalent to ``expr``, but has only + ``&``, ``|``, and ``~`` as logical + operators. + + Examples + ======== + + >>> from sympy.logic.boolalg import Implies, Equivalent, \ + eliminate_implications + >>> from sympy.abc import A, B, C + >>> eliminate_implications(Implies(A, B)) + B | ~A + >>> eliminate_implications(Equivalent(A, B)) + (A | ~B) & (B | ~A) + >>> eliminate_implications(Equivalent(A, B, C)) + (A | ~C) & (B | ~A) & (C | ~B) + + """ + return to_nnf(expr, simplify=False) + + +def is_literal(expr): + """ + Returns True if expr is a literal, else False. + + Examples + ======== + + >>> from sympy import Or, Q + >>> from sympy.abc import A, B + >>> from sympy.logic.boolalg import is_literal + >>> is_literal(A) + True + >>> is_literal(~A) + True + >>> is_literal(Q.zero(A)) + True + >>> is_literal(A + B) + True + >>> is_literal(Or(A, B)) + False + + """ + from sympy.assumptions import AppliedPredicate + + if isinstance(expr, Not): + return is_literal(expr.args[0]) + elif expr in (True, False) or isinstance(expr, AppliedPredicate) or expr.is_Atom: + return True + elif not isinstance(expr, BooleanFunction) and all( + (isinstance(expr, AppliedPredicate) or a.is_Atom) for a in expr.args): + return True + return False + + +def to_int_repr(clauses, symbols): + """ + Takes clauses in CNF format and puts them into an integer representation. + + Examples + ======== + + >>> from sympy.logic.boolalg import to_int_repr + >>> from sympy.abc import x, y + >>> to_int_repr([x | y, y], [x, y]) == [{1, 2}, {2}] + True + + """ + + # Convert the symbol list into a dict + symbols = dict(zip(symbols, range(1, len(symbols) + 1))) + + def append_symbol(arg, symbols): + if isinstance(arg, Not): + return -symbols[arg.args[0]] + else: + return symbols[arg] + + return [{append_symbol(arg, symbols) for arg in Or.make_args(c)} + for c in clauses] + + +def term_to_integer(term): + """ + Return an integer corresponding to the base-2 digits given by *term*. + + Parameters + ========== + + term : a string or list of ones and zeros + + Examples + ======== + + >>> from sympy.logic.boolalg import term_to_integer + >>> term_to_integer([1, 0, 0]) + 4 + >>> term_to_integer('100') + 4 + + """ + + return int(''.join(list(map(str, list(term)))), 2) + + +integer_to_term = ibin # XXX could delete? + + +def truth_table(expr, variables, input=True): + """ + Return a generator of all possible configurations of the input variables, + and the result of the boolean expression for those values. + + Parameters + ========== + + expr : Boolean expression + + variables : list of variables + + input : bool (default ``True``) + Indicates whether to return the input combinations. + + Examples + ======== + + >>> from sympy.logic.boolalg import truth_table + >>> from sympy.abc import x,y + >>> table = truth_table(x >> y, [x, y]) + >>> for t in table: + ... print('{0} -> {1}'.format(*t)) + [0, 0] -> True + [0, 1] -> True + [1, 0] -> False + [1, 1] -> True + + >>> table = truth_table(x | y, [x, y]) + >>> list(table) + [([0, 0], False), ([0, 1], True), ([1, 0], True), ([1, 1], True)] + + If ``input`` is ``False``, ``truth_table`` returns only a list of truth values. + In this case, the corresponding input values of variables can be + deduced from the index of a given output. + + >>> from sympy.utilities.iterables import ibin + >>> vars = [y, x] + >>> values = truth_table(x >> y, vars, input=False) + >>> values = list(values) + >>> values + [True, False, True, True] + + >>> for i, value in enumerate(values): + ... print('{0} -> {1}'.format(list(zip( + ... vars, ibin(i, len(vars)))), value)) + [(y, 0), (x, 0)] -> True + [(y, 0), (x, 1)] -> False + [(y, 1), (x, 0)] -> True + [(y, 1), (x, 1)] -> True + + """ + variables = [sympify(v) for v in variables] + + expr = sympify(expr) + if not isinstance(expr, BooleanFunction) and not is_literal(expr): + return + + table = product((0, 1), repeat=len(variables)) + for term in table: + value = expr.xreplace(dict(zip(variables, term))) + + if input: + yield list(term), value + else: + yield value + + +def _check_pair(minterm1, minterm2): + """ + Checks if a pair of minterms differs by only one bit. If yes, returns + index, else returns `-1`. + """ + # Early termination seems to be faster than list comprehension, + # at least for large examples. + index = -1 + for x, i in enumerate(minterm1): # zip(minterm1, minterm2) is slower + if i != minterm2[x]: + if index == -1: + index = x + else: + return -1 + return index + + +def _convert_to_varsSOP(minterm, variables): + """ + Converts a term in the expansion of a function from binary to its + variable form (for SOP). + """ + temp = [variables[n] if val == 1 else Not(variables[n]) + for n, val in enumerate(minterm) if val != 3] + return And(*temp) + + +def _convert_to_varsPOS(maxterm, variables): + """ + Converts a term in the expansion of a function from binary to its + variable form (for POS). + """ + temp = [variables[n] if val == 0 else Not(variables[n]) + for n, val in enumerate(maxterm) if val != 3] + return Or(*temp) + + +def _convert_to_varsANF(term, variables): + """ + Converts a term in the expansion of a function from binary to its + variable form (for ANF). + + Parameters + ========== + + term : list of 1's and 0's (complementation pattern) + variables : list of variables + + """ + temp = [variables[n] for n, t in enumerate(term) if t == 1] + + if not temp: + return true + + return And(*temp) + + +def _get_odd_parity_terms(n): + """ + Returns a list of lists, with all possible combinations of n zeros and ones + with an odd number of ones. + """ + return [e for e in [ibin(i, n) for i in range(2**n)] if sum(e) % 2 == 1] + + +def _get_even_parity_terms(n): + """ + Returns a list of lists, with all possible combinations of n zeros and ones + with an even number of ones. + """ + return [e for e in [ibin(i, n) for i in range(2**n)] if sum(e) % 2 == 0] + + +def _simplified_pairs(terms): + """ + Reduces a set of minterms, if possible, to a simplified set of minterms + with one less variable in the terms using QM method. + """ + if not terms: + return [] + + simplified_terms = [] + todo = list(range(len(terms))) + + # Count number of ones as _check_pair can only potentially match if there + # is at most a difference of a single one + termdict = defaultdict(list) + for n, term in enumerate(terms): + ones = sum(1 for t in term if t == 1) + termdict[ones].append(n) + + variables = len(terms[0]) + for k in range(variables): + for i in termdict[k]: + for j in termdict[k+1]: + index = _check_pair(terms[i], terms[j]) + if index != -1: + # Mark terms handled + todo[i] = todo[j] = None + # Copy old term + newterm = terms[i][:] + # Set differing position to don't care + newterm[index] = 3 + # Add if not already there + if newterm not in simplified_terms: + simplified_terms.append(newterm) + + if simplified_terms: + # Further simplifications only among the new terms + simplified_terms = _simplified_pairs(simplified_terms) + + # Add remaining, non-simplified, terms + simplified_terms.extend([terms[i] for i in todo if i is not None]) + return simplified_terms + + +def _rem_redundancy(l1, terms): + """ + After the truth table has been sufficiently simplified, use the prime + implicant table method to recognize and eliminate redundant pairs, + and return the essential arguments. + """ + + if not terms: + return [] + + nterms = len(terms) + nl1 = len(l1) + + # Create dominating matrix + dommatrix = [[0]*nl1 for n in range(nterms)] + colcount = [0]*nl1 + rowcount = [0]*nterms + for primei, prime in enumerate(l1): + for termi, term in enumerate(terms): + # Check prime implicant covering term + if all(t == 3 or t == mt for t, mt in zip(prime, term)): + dommatrix[termi][primei] = 1 + colcount[primei] += 1 + rowcount[termi] += 1 + + # Keep track if anything changed + anythingchanged = True + # Then, go again + while anythingchanged: + anythingchanged = False + + for rowi in range(nterms): + # Still non-dominated? + if rowcount[rowi]: + row = dommatrix[rowi] + for row2i in range(nterms): + # Still non-dominated? + if rowi != row2i and rowcount[rowi] and (rowcount[rowi] <= rowcount[row2i]): + row2 = dommatrix[row2i] + if all(row2[n] >= row[n] for n in range(nl1)): + # row2 dominating row, remove row2 + rowcount[row2i] = 0 + anythingchanged = True + for primei, prime in enumerate(row2): + if prime: + # Make corresponding entry 0 + dommatrix[row2i][primei] = 0 + colcount[primei] -= 1 + + colcache = {} + + for coli in range(nl1): + # Still non-dominated? + if colcount[coli]: + if coli in colcache: + col = colcache[coli] + else: + col = [dommatrix[i][coli] for i in range(nterms)] + colcache[coli] = col + for col2i in range(nl1): + # Still non-dominated? + if coli != col2i and colcount[col2i] and (colcount[coli] >= colcount[col2i]): + if col2i in colcache: + col2 = colcache[col2i] + else: + col2 = [dommatrix[i][col2i] for i in range(nterms)] + colcache[col2i] = col2 + if all(col[n] >= col2[n] for n in range(nterms)): + # col dominating col2, remove col2 + colcount[col2i] = 0 + anythingchanged = True + for termi, term in enumerate(col2): + if term and dommatrix[termi][col2i]: + # Make corresponding entry 0 + dommatrix[termi][col2i] = 0 + rowcount[termi] -= 1 + + if not anythingchanged: + # Heuristically select the prime implicant covering most terms + maxterms = 0 + bestcolidx = -1 + for coli in range(nl1): + s = colcount[coli] + if s > maxterms: + bestcolidx = coli + maxterms = s + + # In case we found a prime implicant covering at least two terms + if bestcolidx != -1 and maxterms > 1: + for primei, prime in enumerate(l1): + if primei != bestcolidx: + for termi, term in enumerate(colcache[bestcolidx]): + if term and dommatrix[termi][primei]: + # Make corresponding entry 0 + dommatrix[termi][primei] = 0 + anythingchanged = True + rowcount[termi] -= 1 + colcount[primei] -= 1 + + return [l1[i] for i in range(nl1) if colcount[i]] + + +def _input_to_binlist(inputlist, variables): + binlist = [] + bits = len(variables) + for val in inputlist: + if isinstance(val, int): + binlist.append(ibin(val, bits)) + elif isinstance(val, dict): + nonspecvars = list(variables) + for key in val.keys(): + nonspecvars.remove(key) + for t in product((0, 1), repeat=len(nonspecvars)): + d = dict(zip(nonspecvars, t)) + d.update(val) + binlist.append([d[v] for v in variables]) + elif isinstance(val, (list, tuple)): + if len(val) != bits: + raise ValueError("Each term must contain {bits} bits as there are" + "\n{bits} variables (or be an integer)." + "".format(bits=bits)) + binlist.append(list(val)) + else: + raise TypeError("A term list can only contain lists," + " ints or dicts.") + return binlist + + +def SOPform(variables, minterms, dontcares=None): + """ + The SOPform function uses simplified_pairs and a redundant group- + eliminating algorithm to convert the list of all input combos that + generate '1' (the minterms) into the smallest sum-of-products form. + + The variables must be given as the first argument. + + Return a logical :py:class:`~.Or` function (i.e., the "sum of products" or + "SOP" form) that gives the desired outcome. If there are inputs that can + be ignored, pass them as a list, too. + + The result will be one of the (perhaps many) functions that satisfy + the conditions. + + Examples + ======== + + >>> from sympy.logic import SOPform + >>> from sympy import symbols + >>> w, x, y, z = symbols('w x y z') + >>> minterms = [[0, 0, 0, 1], [0, 0, 1, 1], + ... [0, 1, 1, 1], [1, 0, 1, 1], [1, 1, 1, 1]] + >>> dontcares = [[0, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 1]] + >>> SOPform([w, x, y, z], minterms, dontcares) + (y & z) | (~w & ~x) + + The terms can also be represented as integers: + + >>> minterms = [1, 3, 7, 11, 15] + >>> dontcares = [0, 2, 5] + >>> SOPform([w, x, y, z], minterms, dontcares) + (y & z) | (~w & ~x) + + They can also be specified using dicts, which does not have to be fully + specified: + + >>> minterms = [{w: 0, x: 1}, {y: 1, z: 1, x: 0}] + >>> SOPform([w, x, y, z], minterms) + (x & ~w) | (y & z & ~x) + + Or a combination: + + >>> minterms = [4, 7, 11, [1, 1, 1, 1]] + >>> dontcares = [{w : 0, x : 0, y: 0}, 5] + >>> SOPform([w, x, y, z], minterms, dontcares) + (w & y & z) | (~w & ~y) | (x & z & ~w) + + See also + ======== + + POSform + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Quine-McCluskey_algorithm + .. [2] https://en.wikipedia.org/wiki/Don%27t-care_term + + """ + if not minterms: + return false + + variables = tuple(map(sympify, variables)) + + + minterms = _input_to_binlist(minterms, variables) + dontcares = _input_to_binlist((dontcares or []), variables) + for d in dontcares: + if d in minterms: + raise ValueError('%s in minterms is also in dontcares' % d) + + return _sop_form(variables, minterms, dontcares) + + +def _sop_form(variables, minterms, dontcares): + new = _simplified_pairs(minterms + dontcares) + essential = _rem_redundancy(new, minterms) + return Or(*[_convert_to_varsSOP(x, variables) for x in essential]) + + +def POSform(variables, minterms, dontcares=None): + """ + The POSform function uses simplified_pairs and a redundant-group + eliminating algorithm to convert the list of all input combinations + that generate '1' (the minterms) into the smallest product-of-sums form. + + The variables must be given as the first argument. + + Return a logical :py:class:`~.And` function (i.e., the "product of sums" + or "POS" form) that gives the desired outcome. If there are inputs that can + be ignored, pass them as a list, too. + + The result will be one of the (perhaps many) functions that satisfy + the conditions. + + Examples + ======== + + >>> from sympy.logic import POSform + >>> from sympy import symbols + >>> w, x, y, z = symbols('w x y z') + >>> minterms = [[0, 0, 0, 1], [0, 0, 1, 1], [0, 1, 1, 1], + ... [1, 0, 1, 1], [1, 1, 1, 1]] + >>> dontcares = [[0, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 1]] + >>> POSform([w, x, y, z], minterms, dontcares) + z & (y | ~w) + + The terms can also be represented as integers: + + >>> minterms = [1, 3, 7, 11, 15] + >>> dontcares = [0, 2, 5] + >>> POSform([w, x, y, z], minterms, dontcares) + z & (y | ~w) + + They can also be specified using dicts, which does not have to be fully + specified: + + >>> minterms = [{w: 0, x: 1}, {y: 1, z: 1, x: 0}] + >>> POSform([w, x, y, z], minterms) + (x | y) & (x | z) & (~w | ~x) + + Or a combination: + + >>> minterms = [4, 7, 11, [1, 1, 1, 1]] + >>> dontcares = [{w : 0, x : 0, y: 0}, 5] + >>> POSform([w, x, y, z], minterms, dontcares) + (w | x) & (y | ~w) & (z | ~y) + + See also + ======== + + SOPform + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Quine-McCluskey_algorithm + .. [2] https://en.wikipedia.org/wiki/Don%27t-care_term + + """ + if not minterms: + return false + + variables = tuple(map(sympify, variables)) + minterms = _input_to_binlist(minterms, variables) + dontcares = _input_to_binlist((dontcares or []), variables) + for d in dontcares: + if d in minterms: + raise ValueError('%s in minterms is also in dontcares' % d) + + maxterms = [] + for t in product((0, 1), repeat=len(variables)): + t = list(t) + if (t not in minterms) and (t not in dontcares): + maxterms.append(t) + + new = _simplified_pairs(maxterms + dontcares) + essential = _rem_redundancy(new, maxterms) + return And(*[_convert_to_varsPOS(x, variables) for x in essential]) + + +def ANFform(variables, truthvalues): + """ + The ANFform function converts the list of truth values to + Algebraic Normal Form (ANF). + + The variables must be given as the first argument. + + Return True, False, logical :py:class:`~.And` function (i.e., the + "Zhegalkin monomial") or logical :py:class:`~.Xor` function (i.e., + the "Zhegalkin polynomial"). When True and False + are represented by 1 and 0, respectively, then + :py:class:`~.And` is multiplication and :py:class:`~.Xor` is addition. + + Formally a "Zhegalkin monomial" is the product (logical + And) of a finite set of distinct variables, including + the empty set whose product is denoted 1 (True). + A "Zhegalkin polynomial" is the sum (logical Xor) of a + set of Zhegalkin monomials, with the empty set denoted + by 0 (False). + + Parameters + ========== + + variables : list of variables + truthvalues : list of 1's and 0's (result column of truth table) + + Examples + ======== + >>> from sympy.logic.boolalg import ANFform + >>> from sympy.abc import x, y + >>> ANFform([x], [1, 0]) + x ^ True + >>> ANFform([x, y], [0, 1, 1, 1]) + x ^ y ^ (x & y) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Zhegalkin_polynomial + + """ + + n_vars = len(variables) + n_values = len(truthvalues) + + if n_values != 2 ** n_vars: + raise ValueError("The number of truth values must be equal to 2^%d, " + "got %d" % (n_vars, n_values)) + + variables = tuple(map(sympify, variables)) + + coeffs = anf_coeffs(truthvalues) + terms = [] + + for i, t in enumerate(product((0, 1), repeat=n_vars)): + if coeffs[i] == 1: + terms.append(t) + + return Xor(*[_convert_to_varsANF(x, variables) for x in terms], + remove_true=False) + + +def anf_coeffs(truthvalues): + """ + Convert a list of truth values of some boolean expression + to the list of coefficients of the polynomial mod 2 (exclusive + disjunction) representing the boolean expression in ANF + (i.e., the "Zhegalkin polynomial"). + + There are `2^n` possible Zhegalkin monomials in `n` variables, since + each monomial is fully specified by the presence or absence of + each variable. + + We can enumerate all the monomials. For example, boolean + function with four variables ``(a, b, c, d)`` can contain + up to `2^4 = 16` monomials. The 13-th monomial is the + product ``a & b & d``, because 13 in binary is 1, 1, 0, 1. + + A given monomial's presence or absence in a polynomial corresponds + to that monomial's coefficient being 1 or 0 respectively. + + Examples + ======== + >>> from sympy.logic.boolalg import anf_coeffs, bool_monomial, Xor + >>> from sympy.abc import a, b, c + >>> truthvalues = [0, 1, 1, 0, 0, 1, 0, 1] + >>> coeffs = anf_coeffs(truthvalues) + >>> coeffs + [0, 1, 1, 0, 0, 0, 1, 0] + >>> polynomial = Xor(*[ + ... bool_monomial(k, [a, b, c]) + ... for k, coeff in enumerate(coeffs) if coeff == 1 + ... ]) + >>> polynomial + b ^ c ^ (a & b) + + """ + + s = '{:b}'.format(len(truthvalues)) + n = len(s) - 1 + + if len(truthvalues) != 2**n: + raise ValueError("The number of truth values must be a power of two, " + "got %d" % len(truthvalues)) + + coeffs = [[v] for v in truthvalues] + + for i in range(n): + tmp = [] + for j in range(2 ** (n-i-1)): + tmp.append(coeffs[2*j] + + list(map(lambda x, y: x^y, coeffs[2*j], coeffs[2*j+1]))) + coeffs = tmp + + return coeffs[0] + + +def bool_minterm(k, variables): + """ + Return the k-th minterm. + + Minterms are numbered by a binary encoding of the complementation + pattern of the variables. This convention assigns the value 1 to + the direct form and 0 to the complemented form. + + Parameters + ========== + + k : int or list of 1's and 0's (complementation pattern) + variables : list of variables + + Examples + ======== + + >>> from sympy.logic.boolalg import bool_minterm + >>> from sympy.abc import x, y, z + >>> bool_minterm([1, 0, 1], [x, y, z]) + x & z & ~y + >>> bool_minterm(6, [x, y, z]) + x & y & ~z + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Canonical_normal_form#Indexing_minterms + + """ + if isinstance(k, int): + k = ibin(k, len(variables)) + variables = tuple(map(sympify, variables)) + return _convert_to_varsSOP(k, variables) + + +def bool_maxterm(k, variables): + """ + Return the k-th maxterm. + + Each maxterm is assigned an index based on the opposite + conventional binary encoding used for minterms. The maxterm + convention assigns the value 0 to the direct form and 1 to + the complemented form. + + Parameters + ========== + + k : int or list of 1's and 0's (complementation pattern) + variables : list of variables + + Examples + ======== + >>> from sympy.logic.boolalg import bool_maxterm + >>> from sympy.abc import x, y, z + >>> bool_maxterm([1, 0, 1], [x, y, z]) + y | ~x | ~z + >>> bool_maxterm(6, [x, y, z]) + z | ~x | ~y + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Canonical_normal_form#Indexing_maxterms + + """ + if isinstance(k, int): + k = ibin(k, len(variables)) + variables = tuple(map(sympify, variables)) + return _convert_to_varsPOS(k, variables) + + +def bool_monomial(k, variables): + """ + Return the k-th monomial. + + Monomials are numbered by a binary encoding of the presence and + absences of the variables. This convention assigns the value + 1 to the presence of variable and 0 to the absence of variable. + + Each boolean function can be uniquely represented by a + Zhegalkin Polynomial (Algebraic Normal Form). The Zhegalkin + Polynomial of the boolean function with `n` variables can contain + up to `2^n` monomials. We can enumerate all the monomials. + Each monomial is fully specified by the presence or absence + of each variable. + + For example, boolean function with four variables ``(a, b, c, d)`` + can contain up to `2^4 = 16` monomials. The 13-th monomial is the + product ``a & b & d``, because 13 in binary is 1, 1, 0, 1. + + Parameters + ========== + + k : int or list of 1's and 0's + variables : list of variables + + Examples + ======== + >>> from sympy.logic.boolalg import bool_monomial + >>> from sympy.abc import x, y, z + >>> bool_monomial([1, 0, 1], [x, y, z]) + x & z + >>> bool_monomial(6, [x, y, z]) + x & y + + """ + if isinstance(k, int): + k = ibin(k, len(variables)) + variables = tuple(map(sympify, variables)) + return _convert_to_varsANF(k, variables) + + +def _find_predicates(expr): + """Helper to find logical predicates in BooleanFunctions. + + A logical predicate is defined here as anything within a BooleanFunction + that is not a BooleanFunction itself. + + """ + if not isinstance(expr, BooleanFunction): + return {expr} + return set().union(*(map(_find_predicates, expr.args))) + + +def simplify_logic(expr, form=None, deep=True, force=False, dontcare=None): + """ + This function simplifies a boolean function to its simplified version + in SOP or POS form. The return type is an :py:class:`~.Or` or + :py:class:`~.And` object in SymPy. + + Parameters + ========== + + expr : Boolean + + form : string (``'cnf'`` or ``'dnf'``) or ``None`` (default). + If ``'cnf'`` or ``'dnf'``, the simplest expression in the corresponding + normal form is returned; if ``None``, the answer is returned + according to the form with fewest args (in CNF by default). + + deep : bool (default ``True``) + Indicates whether to recursively simplify any + non-boolean functions contained within the input. + + force : bool (default ``False``) + As the simplifications require exponential time in the number + of variables, there is by default a limit on expressions with + 8 variables. When the expression has more than 8 variables + only symbolical simplification (controlled by ``deep``) is + made. By setting ``force`` to ``True``, this limit is removed. Be + aware that this can lead to very long simplification times. + + dontcare : Boolean + Optimize expression under the assumption that inputs where this + expression is true are don't care. This is useful in e.g. Piecewise + conditions, where later conditions do not need to consider inputs that + are converted by previous conditions. For example, if a previous + condition is ``And(A, B)``, the simplification of expr can be made + with don't cares for ``And(A, B)``. + + Examples + ======== + + >>> from sympy.logic import simplify_logic + >>> from sympy.abc import x, y, z + >>> b = (~x & ~y & ~z) | ( ~x & ~y & z) + >>> simplify_logic(b) + ~x & ~y + >>> simplify_logic(x | y, dontcare=y) + x + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Don%27t-care_term + + """ + + if form not in (None, 'cnf', 'dnf'): + raise ValueError("form can be cnf or dnf only") + expr = sympify(expr) + # check for quick exit if form is given: right form and all args are + # literal and do not involve Not + if form: + form_ok = False + if form == 'cnf': + form_ok = is_cnf(expr) + elif form == 'dnf': + form_ok = is_dnf(expr) + + if form_ok and all(is_literal(a) + for a in expr.args): + return expr + from sympy.core.relational import Relational + if deep: + variables = expr.atoms(Relational) + from sympy.simplify.simplify import simplify + s = tuple(map(simplify, variables)) + expr = expr.xreplace(dict(zip(variables, s))) + if not isinstance(expr, BooleanFunction): + return expr + # Replace Relationals with Dummys to possibly + # reduce the number of variables + repl = {} + undo = {} + from sympy.core.symbol import Dummy + variables = expr.atoms(Relational) + if dontcare is not None: + dontcare = sympify(dontcare) + variables.update(dontcare.atoms(Relational)) + while variables: + var = variables.pop() + if var.is_Relational: + d = Dummy() + undo[d] = var + repl[var] = d + nvar = var.negated + if nvar in variables: + repl[nvar] = Not(d) + variables.remove(nvar) + + expr = expr.xreplace(repl) + + if dontcare is not None: + dontcare = dontcare.xreplace(repl) + + # Get new variables after replacing + variables = _find_predicates(expr) + if not force and len(variables) > 8: + return expr.xreplace(undo) + if dontcare is not None: + # Add variables from dontcare + dcvariables = _find_predicates(dontcare) + variables.update(dcvariables) + # if too many restore to variables only + if not force and len(variables) > 8: + variables = _find_predicates(expr) + dontcare = None + # group into constants and variable values + c, v = sift(ordered(variables), lambda x: x in (True, False), binary=True) + variables = c + v + # standardize constants to be 1 or 0 in keeping with truthtable + c = [1 if i == True else 0 for i in c] + truthtable = _get_truthtable(v, expr, c) + if dontcare is not None: + dctruthtable = _get_truthtable(v, dontcare, c) + truthtable = [t for t in truthtable if t not in dctruthtable] + else: + dctruthtable = [] + big = len(truthtable) >= (2 ** (len(variables) - 1)) + if form == 'dnf' or form is None and big: + return _sop_form(variables, truthtable, dctruthtable).xreplace(undo) + return POSform(variables, truthtable, dctruthtable).xreplace(undo) + + +def _get_truthtable(variables, expr, const): + """ Return a list of all combinations leading to a True result for ``expr``. + """ + _variables = variables.copy() + def _get_tt(inputs): + if _variables: + v = _variables.pop() + tab = [[i[0].xreplace({v: false}), [0] + i[1]] for i in inputs if i[0] is not false] + tab.extend([[i[0].xreplace({v: true}), [1] + i[1]] for i in inputs if i[0] is not false]) + return _get_tt(tab) + return inputs + res = [const + k[1] for k in _get_tt([[expr, []]]) if k[0]] + if res == [[]]: + return [] + else: + return res + + +def _finger(eq): + """ + Assign a 5-item fingerprint to each symbol in the equation: + [ + # of times it appeared as a Symbol; + # of times it appeared as a Not(symbol); + # of times it appeared as a Symbol in an And or Or; + # of times it appeared as a Not(Symbol) in an And or Or; + a sorted tuple of tuples, (i, j, k), where i is the number of arguments + in an And or Or with which it appeared as a Symbol, and j is + the number of arguments that were Not(Symbol); k is the number + of times that (i, j) was seen. + ] + + Examples + ======== + + >>> from sympy.logic.boolalg import _finger as finger + >>> from sympy import And, Or, Not, Xor, to_cnf, symbols + >>> from sympy.abc import a, b, x, y + >>> eq = Or(And(Not(y), a), And(Not(y), b), And(x, y)) + >>> dict(finger(eq)) + {(0, 0, 1, 0, ((2, 0, 1),)): [x], + (0, 0, 1, 0, ((2, 1, 1),)): [a, b], + (0, 0, 1, 2, ((2, 0, 1),)): [y]} + >>> dict(finger(x & ~y)) + {(0, 1, 0, 0, ()): [y], (1, 0, 0, 0, ()): [x]} + + In the following, the (5, 2, 6) means that there were 6 Or + functions in which a symbol appeared as itself amongst 5 arguments in + which there were also 2 negated symbols, e.g. ``(a0 | a1 | a2 | ~a3 | ~a4)`` + is counted once for a0, a1 and a2. + + >>> dict(finger(to_cnf(Xor(*symbols('a:5'))))) + {(0, 0, 8, 8, ((5, 0, 1), (5, 2, 6), (5, 4, 1))): [a0, a1, a2, a3, a4]} + + The equation must not have more than one level of nesting: + + >>> dict(finger(And(Or(x, y), y))) + {(0, 0, 1, 0, ((2, 0, 1),)): [x], (1, 0, 1, 0, ((2, 0, 1),)): [y]} + >>> dict(finger(And(Or(x, And(a, x)), y))) + Traceback (most recent call last): + ... + NotImplementedError: unexpected level of nesting + + So y and x have unique fingerprints, but a and b do not. + """ + f = eq.free_symbols + d = dict(list(zip(f, [[0]*4 + [defaultdict(int)] for fi in f]))) + for a in eq.args: + if a.is_Symbol: + d[a][0] += 1 + elif a.is_Not: + d[a.args[0]][1] += 1 + else: + o = len(a.args), sum(isinstance(ai, Not) for ai in a.args) + for ai in a.args: + if ai.is_Symbol: + d[ai][2] += 1 + d[ai][-1][o] += 1 + elif ai.is_Not: + d[ai.args[0]][3] += 1 + else: + raise NotImplementedError('unexpected level of nesting') + inv = defaultdict(list) + for k, v in ordered(iter(d.items())): + v[-1] = tuple(sorted([i + (j,) for i, j in v[-1].items()])) + inv[tuple(v)].append(k) + return inv + + +def bool_map(bool1, bool2): + """ + Return the simplified version of *bool1*, and the mapping of variables + that makes the two expressions *bool1* and *bool2* represent the same + logical behaviour for some correspondence between the variables + of each. + If more than one mappings of this sort exist, one of them + is returned. + + For example, ``And(x, y)`` is logically equivalent to ``And(a, b)`` for + the mapping ``{x: a, y: b}`` or ``{x: b, y: a}``. + If no such mapping exists, return ``False``. + + Examples + ======== + + >>> from sympy import SOPform, bool_map, Or, And, Not, Xor + >>> from sympy.abc import w, x, y, z, a, b, c, d + >>> function1 = SOPform([x, z, y],[[1, 0, 1], [0, 0, 1]]) + >>> function2 = SOPform([a, b, c],[[1, 0, 1], [1, 0, 0]]) + >>> bool_map(function1, function2) + (y & ~z, {y: a, z: b}) + + The results are not necessarily unique, but they are canonical. Here, + ``(w, z)`` could be ``(a, d)`` or ``(d, a)``: + + >>> eq = Or(And(Not(y), w), And(Not(y), z), And(x, y)) + >>> eq2 = Or(And(Not(c), a), And(Not(c), d), And(b, c)) + >>> bool_map(eq, eq2) + ((x & y) | (w & ~y) | (z & ~y), {w: a, x: b, y: c, z: d}) + >>> eq = And(Xor(a, b), c, And(c,d)) + >>> bool_map(eq, eq.subs(c, x)) + (c & d & (a | b) & (~a | ~b), {a: a, b: b, c: d, d: x}) + + """ + + def match(function1, function2): + """Return the mapping that equates variables between two + simplified boolean expressions if possible. + + By "simplified" we mean that a function has been denested + and is either an And (or an Or) whose arguments are either + symbols (x), negated symbols (Not(x)), or Or (or an And) whose + arguments are only symbols or negated symbols. For example, + ``And(x, Not(y), Or(w, Not(z)))``. + + Basic.match is not robust enough (see issue 4835) so this is + a workaround that is valid for simplified boolean expressions + """ + + # do some quick checks + if function1.__class__ != function2.__class__: + return None # maybe simplification makes them the same? + if len(function1.args) != len(function2.args): + return None # maybe simplification makes them the same? + if function1.is_Symbol: + return {function1: function2} + + # get the fingerprint dictionaries + f1 = _finger(function1) + f2 = _finger(function2) + + # more quick checks + if len(f1) != len(f2): + return False + + # assemble the match dictionary if possible + matchdict = {} + for k in f1.keys(): + if k not in f2: + return False + if len(f1[k]) != len(f2[k]): + return False + for i, x in enumerate(f1[k]): + matchdict[x] = f2[k][i] + return matchdict + + a = simplify_logic(bool1) + b = simplify_logic(bool2) + m = match(a, b) + if m: + return a, m + return m + + +def _apply_patternbased_simplification(rv, patterns, measure, + dominatingvalue, + replacementvalue=None, + threeterm_patterns=None): + """ + Replace patterns of Relational + + Parameters + ========== + + rv : Expr + Boolean expression + + patterns : tuple + Tuple of tuples, with (pattern to simplify, simplified pattern) with + two terms. + + measure : function + Simplification measure. + + dominatingvalue : Boolean or ``None`` + The dominating value for the function of consideration. + For example, for :py:class:`~.And` ``S.false`` is dominating. + As soon as one expression is ``S.false`` in :py:class:`~.And`, + the whole expression is ``S.false``. + + replacementvalue : Boolean or ``None``, optional + The resulting value for the whole expression if one argument + evaluates to ``dominatingvalue``. + For example, for :py:class:`~.Nand` ``S.false`` is dominating, but + in this case the resulting value is ``S.true``. Default is ``None``. + If ``replacementvalue`` is ``None`` and ``dominatingvalue`` is not + ``None``, ``replacementvalue = dominatingvalue``. + + threeterm_patterns : tuple, optional + Tuple of tuples, with (pattern to simplify, simplified pattern) with + three terms. + + """ + from sympy.core.relational import Relational, _canonical + + if replacementvalue is None and dominatingvalue is not None: + replacementvalue = dominatingvalue + # Use replacement patterns for Relationals + Rel, nonRel = sift(rv.args, lambda i: isinstance(i, Relational), + binary=True) + if len(Rel) <= 1: + return rv + Rel, nonRealRel = sift(Rel, lambda i: not any(s.is_real is False + for s in i.free_symbols), + binary=True) + Rel = [i.canonical for i in Rel] + + if threeterm_patterns and len(Rel) >= 3: + Rel = _apply_patternbased_threeterm_simplification(Rel, + threeterm_patterns, rv.func, dominatingvalue, + replacementvalue, measure) + + Rel = _apply_patternbased_twoterm_simplification(Rel, patterns, + rv.func, dominatingvalue, replacementvalue, measure) + + rv = rv.func(*([_canonical(i) for i in ordered(Rel)] + + nonRel + nonRealRel)) + return rv + + +def _apply_patternbased_twoterm_simplification(Rel, patterns, func, + dominatingvalue, + replacementvalue, + measure): + """ Apply pattern-based two-term simplification.""" + from sympy.functions.elementary.miscellaneous import Min, Max + from sympy.core.relational import Ge, Gt, _Inequality + changed = True + while changed and len(Rel) >= 2: + changed = False + # Use only < or <= + Rel = [r.reversed if isinstance(r, (Ge, Gt)) else r for r in Rel] + # Sort based on ordered + Rel = list(ordered(Rel)) + # Eq and Ne must be tested reversed as well + rtmp = [(r, ) if isinstance(r, _Inequality) else (r, r.reversed) for r in Rel] + # Create a list of possible replacements + results = [] + # Try all combinations of possibly reversed relational + for ((i, pi), (j, pj)) in combinations(enumerate(rtmp), 2): + for pattern, simp in patterns: + res = [] + for p1, p2 in product(pi, pj): + # use SymPy matching + oldexpr = Tuple(p1, p2) + tmpres = oldexpr.match(pattern) + if tmpres: + res.append((tmpres, oldexpr)) + + if res: + for tmpres, oldexpr in res: + # we have a matching, compute replacement + np = simp.xreplace(tmpres) + if np == dominatingvalue: + # if dominatingvalue, the whole expression + # will be replacementvalue + return [replacementvalue] + # add replacement + if not isinstance(np, ITE) and not np.has(Min, Max): + # We only want to use ITE and Min/Max replacements if + # they simplify to a relational + costsaving = measure(func(*oldexpr.args)) - measure(np) + if costsaving > 0: + results.append((costsaving, ([i, j], np))) + if results: + # Sort results based on complexity + results = sorted(results, + key=lambda pair: pair[0], reverse=True) + # Replace the one providing most simplification + replacement = results[0][1] + idx, newrel = replacement + idx.sort() + # Remove the old relationals + for index in reversed(idx): + del Rel[index] + if dominatingvalue is None or newrel != Not(dominatingvalue): + # Insert the new one (no need to insert a value that will + # not affect the result) + if newrel.func == func: + for a in newrel.args: + Rel.append(a) + else: + Rel.append(newrel) + # We did change something so try again + changed = True + return Rel + + +def _apply_patternbased_threeterm_simplification(Rel, patterns, func, + dominatingvalue, + replacementvalue, + measure): + """ Apply pattern-based three-term simplification.""" + from sympy.functions.elementary.miscellaneous import Min, Max + from sympy.core.relational import Le, Lt, _Inequality + changed = True + while changed and len(Rel) >= 3: + changed = False + # Use only > or >= + Rel = [r.reversed if isinstance(r, (Le, Lt)) else r for r in Rel] + # Sort based on ordered + Rel = list(ordered(Rel)) + # Create a list of possible replacements + results = [] + # Eq and Ne must be tested reversed as well + rtmp = [(r, ) if isinstance(r, _Inequality) else (r, r.reversed) for r in Rel] + # Try all combinations of possibly reversed relational + for ((i, pi), (j, pj), (k, pk)) in permutations(enumerate(rtmp), 3): + for pattern, simp in patterns: + res = [] + for p1, p2, p3 in product(pi, pj, pk): + # use SymPy matching + oldexpr = Tuple(p1, p2, p3) + tmpres = oldexpr.match(pattern) + if tmpres: + res.append((tmpres, oldexpr)) + + if res: + for tmpres, oldexpr in res: + # we have a matching, compute replacement + np = simp.xreplace(tmpres) + if np == dominatingvalue: + # if dominatingvalue, the whole expression + # will be replacementvalue + return [replacementvalue] + # add replacement + if not isinstance(np, ITE) and not np.has(Min, Max): + # We only want to use ITE and Min/Max replacements if + # they simplify to a relational + costsaving = measure(func(*oldexpr.args)) - measure(np) + if costsaving > 0: + results.append((costsaving, ([i, j, k], np))) + if results: + # Sort results based on complexity + results = sorted(results, + key=lambda pair: pair[0], reverse=True) + # Replace the one providing most simplification + replacement = results[0][1] + idx, newrel = replacement + idx.sort() + # Remove the old relationals + for index in reversed(idx): + del Rel[index] + if dominatingvalue is None or newrel != Not(dominatingvalue): + # Insert the new one (no need to insert a value that will + # not affect the result) + if newrel.func == func: + for a in newrel.args: + Rel.append(a) + else: + Rel.append(newrel) + # We did change something so try again + changed = True + return Rel + + +@cacheit +def _simplify_patterns_and(): + """ Two-term patterns for And.""" + + from sympy.core import Wild + from sympy.core.relational import Eq, Ne, Ge, Gt, Le, Lt + from sympy.functions.elementary.complexes import Abs + from sympy.functions.elementary.miscellaneous import Min, Max + a = Wild('a') + b = Wild('b') + c = Wild('c') + # Relationals patterns should be in alphabetical order + # (pattern1, pattern2, simplified) + # Do not use Ge, Gt + _matchers_and = ((Tuple(Eq(a, b), Lt(a, b)), false), + #(Tuple(Eq(a, b), Lt(b, a)), S.false), + #(Tuple(Le(b, a), Lt(a, b)), S.false), + #(Tuple(Lt(b, a), Le(a, b)), S.false), + (Tuple(Lt(b, a), Lt(a, b)), false), + (Tuple(Eq(a, b), Le(b, a)), Eq(a, b)), + #(Tuple(Eq(a, b), Le(a, b)), Eq(a, b)), + #(Tuple(Le(b, a), Lt(b, a)), Gt(a, b)), + (Tuple(Le(b, a), Le(a, b)), Eq(a, b)), + #(Tuple(Le(b, a), Ne(a, b)), Gt(a, b)), + #(Tuple(Lt(b, a), Ne(a, b)), Gt(a, b)), + (Tuple(Le(a, b), Lt(a, b)), Lt(a, b)), + (Tuple(Le(a, b), Ne(a, b)), Lt(a, b)), + (Tuple(Lt(a, b), Ne(a, b)), Lt(a, b)), + # Sign + (Tuple(Eq(a, b), Eq(a, -b)), And(Eq(a, S.Zero), Eq(b, S.Zero))), + # Min/Max/ITE + (Tuple(Le(b, a), Le(c, a)), Ge(a, Max(b, c))), + (Tuple(Le(b, a), Lt(c, a)), ITE(b > c, Ge(a, b), Gt(a, c))), + (Tuple(Lt(b, a), Lt(c, a)), Gt(a, Max(b, c))), + (Tuple(Le(a, b), Le(a, c)), Le(a, Min(b, c))), + (Tuple(Le(a, b), Lt(a, c)), ITE(b < c, Le(a, b), Lt(a, c))), + (Tuple(Lt(a, b), Lt(a, c)), Lt(a, Min(b, c))), + (Tuple(Le(a, b), Le(c, a)), ITE(Eq(b, c), Eq(a, b), ITE(b < c, false, And(Le(a, b), Ge(a, c))))), + (Tuple(Le(c, a), Le(a, b)), ITE(Eq(b, c), Eq(a, b), ITE(b < c, false, And(Le(a, b), Ge(a, c))))), + (Tuple(Lt(a, b), Lt(c, a)), ITE(b < c, false, And(Lt(a, b), Gt(a, c)))), + (Tuple(Lt(c, a), Lt(a, b)), ITE(b < c, false, And(Lt(a, b), Gt(a, c)))), + (Tuple(Le(a, b), Lt(c, a)), ITE(b <= c, false, And(Le(a, b), Gt(a, c)))), + (Tuple(Le(c, a), Lt(a, b)), ITE(b <= c, false, And(Lt(a, b), Ge(a, c)))), + (Tuple(Eq(a, b), Eq(a, c)), ITE(Eq(b, c), Eq(a, b), false)), + (Tuple(Lt(a, b), Lt(-b, a)), ITE(b > 0, Lt(Abs(a), b), false)), + (Tuple(Le(a, b), Le(-b, a)), ITE(b >= 0, Le(Abs(a), b), false)), + ) + return _matchers_and + + +@cacheit +def _simplify_patterns_and3(): + """ Three-term patterns for And.""" + + from sympy.core import Wild + from sympy.core.relational import Eq, Ge, Gt + + a = Wild('a') + b = Wild('b') + c = Wild('c') + # Relationals patterns should be in alphabetical order + # (pattern1, pattern2, pattern3, simplified) + # Do not use Le, Lt + _matchers_and = ((Tuple(Ge(a, b), Ge(b, c), Gt(c, a)), false), + (Tuple(Ge(a, b), Gt(b, c), Gt(c, a)), false), + (Tuple(Gt(a, b), Gt(b, c), Gt(c, a)), false), + # (Tuple(Ge(c, a), Gt(a, b), Gt(b, c)), S.false), + # Lower bound relations + # Commented out combinations that does not simplify + (Tuple(Ge(a, b), Ge(a, c), Ge(b, c)), And(Ge(a, b), Ge(b, c))), + (Tuple(Ge(a, b), Ge(a, c), Gt(b, c)), And(Ge(a, b), Gt(b, c))), + # (Tuple(Ge(a, b), Gt(a, c), Ge(b, c)), And(Ge(a, b), Ge(b, c))), + (Tuple(Ge(a, b), Gt(a, c), Gt(b, c)), And(Ge(a, b), Gt(b, c))), + # (Tuple(Gt(a, b), Ge(a, c), Ge(b, c)), And(Gt(a, b), Ge(b, c))), + (Tuple(Ge(a, c), Gt(a, b), Gt(b, c)), And(Gt(a, b), Gt(b, c))), + (Tuple(Ge(b, c), Gt(a, b), Gt(a, c)), And(Gt(a, b), Ge(b, c))), + (Tuple(Gt(a, b), Gt(a, c), Gt(b, c)), And(Gt(a, b), Gt(b, c))), + # Upper bound relations + # Commented out combinations that does not simplify + (Tuple(Ge(b, a), Ge(c, a), Ge(b, c)), And(Ge(c, a), Ge(b, c))), + (Tuple(Ge(b, a), Ge(c, a), Gt(b, c)), And(Ge(c, a), Gt(b, c))), + # (Tuple(Ge(b, a), Gt(c, a), Ge(b, c)), And(Gt(c, a), Ge(b, c))), + (Tuple(Ge(b, a), Gt(c, a), Gt(b, c)), And(Gt(c, a), Gt(b, c))), + # (Tuple(Gt(b, a), Ge(c, a), Ge(b, c)), And(Ge(c, a), Ge(b, c))), + (Tuple(Ge(c, a), Gt(b, a), Gt(b, c)), And(Ge(c, a), Gt(b, c))), + (Tuple(Ge(b, c), Gt(b, a), Gt(c, a)), And(Gt(c, a), Ge(b, c))), + (Tuple(Gt(b, a), Gt(c, a), Gt(b, c)), And(Gt(c, a), Gt(b, c))), + # Circular relation + (Tuple(Ge(a, b), Ge(b, c), Ge(c, a)), And(Eq(a, b), Eq(b, c))), + ) + return _matchers_and + + +@cacheit +def _simplify_patterns_or(): + """ Two-term patterns for Or.""" + + from sympy.core import Wild + from sympy.core.relational import Eq, Ne, Ge, Gt, Le, Lt + from sympy.functions.elementary.complexes import Abs + from sympy.functions.elementary.miscellaneous import Min, Max + a = Wild('a') + b = Wild('b') + c = Wild('c') + # Relationals patterns should be in alphabetical order + # (pattern1, pattern2, simplified) + # Do not use Ge, Gt + _matchers_or = ((Tuple(Le(b, a), Le(a, b)), true), + #(Tuple(Le(b, a), Lt(a, b)), true), + (Tuple(Le(b, a), Ne(a, b)), true), + #(Tuple(Le(a, b), Lt(b, a)), true), + #(Tuple(Le(a, b), Ne(a, b)), true), + #(Tuple(Eq(a, b), Le(b, a)), Ge(a, b)), + #(Tuple(Eq(a, b), Lt(b, a)), Ge(a, b)), + (Tuple(Eq(a, b), Le(a, b)), Le(a, b)), + (Tuple(Eq(a, b), Lt(a, b)), Le(a, b)), + #(Tuple(Le(b, a), Lt(b, a)), Ge(a, b)), + (Tuple(Lt(b, a), Lt(a, b)), Ne(a, b)), + (Tuple(Lt(b, a), Ne(a, b)), Ne(a, b)), + (Tuple(Le(a, b), Lt(a, b)), Le(a, b)), + #(Tuple(Lt(a, b), Ne(a, b)), Ne(a, b)), + (Tuple(Eq(a, b), Ne(a, c)), ITE(Eq(b, c), true, Ne(a, c))), + (Tuple(Ne(a, b), Ne(a, c)), ITE(Eq(b, c), Ne(a, b), true)), + # Min/Max/ITE + (Tuple(Le(b, a), Le(c, a)), Ge(a, Min(b, c))), + #(Tuple(Ge(b, a), Ge(c, a)), Ge(Min(b, c), a)), + (Tuple(Le(b, a), Lt(c, a)), ITE(b > c, Lt(c, a), Le(b, a))), + (Tuple(Lt(b, a), Lt(c, a)), Gt(a, Min(b, c))), + #(Tuple(Gt(b, a), Gt(c, a)), Gt(Min(b, c), a)), + (Tuple(Le(a, b), Le(a, c)), Le(a, Max(b, c))), + #(Tuple(Le(b, a), Le(c, a)), Le(Max(b, c), a)), + (Tuple(Le(a, b), Lt(a, c)), ITE(b >= c, Le(a, b), Lt(a, c))), + (Tuple(Lt(a, b), Lt(a, c)), Lt(a, Max(b, c))), + #(Tuple(Lt(b, a), Lt(c, a)), Lt(Max(b, c), a)), + (Tuple(Le(a, b), Le(c, a)), ITE(b >= c, true, Or(Le(a, b), Ge(a, c)))), + (Tuple(Le(c, a), Le(a, b)), ITE(b >= c, true, Or(Le(a, b), Ge(a, c)))), + (Tuple(Lt(a, b), Lt(c, a)), ITE(b > c, true, Or(Lt(a, b), Gt(a, c)))), + (Tuple(Lt(c, a), Lt(a, b)), ITE(b > c, true, Or(Lt(a, b), Gt(a, c)))), + (Tuple(Le(a, b), Lt(c, a)), ITE(b >= c, true, Or(Le(a, b), Gt(a, c)))), + (Tuple(Le(c, a), Lt(a, b)), ITE(b >= c, true, Or(Lt(a, b), Ge(a, c)))), + (Tuple(Lt(b, a), Lt(a, -b)), ITE(b >= 0, Gt(Abs(a), b), true)), + (Tuple(Le(b, a), Le(a, -b)), ITE(b > 0, Ge(Abs(a), b), true)), + ) + return _matchers_or + + +@cacheit +def _simplify_patterns_xor(): + """ Two-term patterns for Xor.""" + + from sympy.functions.elementary.miscellaneous import Min, Max + from sympy.core import Wild + from sympy.core.relational import Eq, Ne, Ge, Gt, Le, Lt + a = Wild('a') + b = Wild('b') + c = Wild('c') + # Relationals patterns should be in alphabetical order + # (pattern1, pattern2, simplified) + # Do not use Ge, Gt + _matchers_xor = (#(Tuple(Le(b, a), Lt(a, b)), true), + #(Tuple(Lt(b, a), Le(a, b)), true), + #(Tuple(Eq(a, b), Le(b, a)), Gt(a, b)), + #(Tuple(Eq(a, b), Lt(b, a)), Ge(a, b)), + (Tuple(Eq(a, b), Le(a, b)), Lt(a, b)), + (Tuple(Eq(a, b), Lt(a, b)), Le(a, b)), + (Tuple(Le(a, b), Lt(a, b)), Eq(a, b)), + (Tuple(Le(a, b), Le(b, a)), Ne(a, b)), + (Tuple(Le(b, a), Ne(a, b)), Le(a, b)), + # (Tuple(Lt(b, a), Lt(a, b)), Ne(a, b)), + (Tuple(Lt(b, a), Ne(a, b)), Lt(a, b)), + # (Tuple(Le(a, b), Lt(a, b)), Eq(a, b)), + # (Tuple(Le(a, b), Ne(a, b)), Ge(a, b)), + # (Tuple(Lt(a, b), Ne(a, b)), Gt(a, b)), + # Min/Max/ITE + (Tuple(Le(b, a), Le(c, a)), + And(Ge(a, Min(b, c)), Lt(a, Max(b, c)))), + (Tuple(Le(b, a), Lt(c, a)), + ITE(b > c, And(Gt(a, c), Lt(a, b)), + And(Ge(a, b), Le(a, c)))), + (Tuple(Lt(b, a), Lt(c, a)), + And(Gt(a, Min(b, c)), Le(a, Max(b, c)))), + (Tuple(Le(a, b), Le(a, c)), + And(Le(a, Max(b, c)), Gt(a, Min(b, c)))), + (Tuple(Le(a, b), Lt(a, c)), + ITE(b < c, And(Lt(a, c), Gt(a, b)), + And(Le(a, b), Ge(a, c)))), + (Tuple(Lt(a, b), Lt(a, c)), + And(Lt(a, Max(b, c)), Ge(a, Min(b, c)))), + ) + return _matchers_xor + + +def simplify_univariate(expr): + """return a simplified version of univariate boolean expression, else ``expr``""" + from sympy.functions.elementary.piecewise import Piecewise + from sympy.core.relational import Eq, Ne + if not isinstance(expr, BooleanFunction): + return expr + if expr.atoms(Eq, Ne): + return expr + c = expr + free = c.free_symbols + if len(free) != 1: + return c + x = free.pop() + ok, i = Piecewise((0, c), evaluate=False + )._intervals(x, err_on_Eq=True) + if not ok: + return c + if not i: + return false + args = [] + for a, b, _, _ in i: + if a is S.NegativeInfinity: + if b is S.Infinity: + c = true + else: + if c.subs(x, b) == True: + c = (x <= b) + else: + c = (x < b) + else: + incl_a = (c.subs(x, a) == True) + incl_b = (c.subs(x, b) == True) + if incl_a and incl_b: + if b.is_infinite: + c = (x >= a) + else: + c = And(a <= x, x <= b) + elif incl_a: + c = And(a <= x, x < b) + elif incl_b: + if b.is_infinite: + c = (x > a) + else: + c = And(a < x, x <= b) + else: + c = And(a < x, x < b) + args.append(c) + return Or(*args) + + +# Classes corresponding to logic gates +# Used in gateinputcount method +BooleanGates = (And, Or, Xor, Nand, Nor, Not, Xnor, ITE) + +def gateinputcount(expr): + """ + Return the total number of inputs for the logic gates realizing the + Boolean expression. + + Returns + ======= + + int + Number of gate inputs + + Note + ==== + + Not all Boolean functions count as gate here, only those that are + considered to be standard gates. These are: :py:class:`~.And`, + :py:class:`~.Or`, :py:class:`~.Xor`, :py:class:`~.Not`, and + :py:class:`~.ITE` (multiplexer). :py:class:`~.Nand`, :py:class:`~.Nor`, + and :py:class:`~.Xnor` will be evaluated to ``Not(And())`` etc. + + Examples + ======== + + >>> from sympy.logic import And, Or, Nand, Not, gateinputcount + >>> from sympy.abc import x, y, z + >>> expr = And(x, y) + >>> gateinputcount(expr) + 2 + >>> gateinputcount(Or(expr, z)) + 4 + + Note that ``Nand`` is automatically evaluated to ``Not(And())`` so + + >>> gateinputcount(Nand(x, y, z)) + 4 + >>> gateinputcount(Not(And(x, y, z))) + 4 + + Although this can be avoided by using ``evaluate=False`` + + >>> gateinputcount(Nand(x, y, z, evaluate=False)) + 3 + + Also note that a comparison will count as a Boolean variable: + + >>> gateinputcount(And(x > z, y >= 2)) + 2 + + As will a symbol: + >>> gateinputcount(x) + 0 + + """ + if not isinstance(expr, Boolean): + raise TypeError("Expression must be Boolean") + if isinstance(expr, BooleanGates): + return len(expr.args) + sum(gateinputcount(x) for x in expr.args) + return 0 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/inference.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/inference.py new file mode 100644 index 0000000000000000000000000000000000000000..c3798231c09ae351ea7e7026d622b834fea3e3fa --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/inference.py @@ -0,0 +1,340 @@ +"""Inference in propositional logic""" + +from sympy.logic.boolalg import And, Not, conjuncts, to_cnf, BooleanFunction +from sympy.core.sorting import ordered +from sympy.core.sympify import sympify +from sympy.external.importtools import import_module + + +def literal_symbol(literal): + """ + The symbol in this literal (without the negation). + + Examples + ======== + + >>> from sympy.abc import A + >>> from sympy.logic.inference import literal_symbol + >>> literal_symbol(A) + A + >>> literal_symbol(~A) + A + + """ + + if literal is True or literal is False: + return literal + elif literal.is_Symbol: + return literal + elif literal.is_Not: + return literal_symbol(literal.args[0]) + else: + raise ValueError("Argument must be a boolean literal.") + + +def satisfiable(expr, algorithm=None, all_models=False, minimal=False, use_lra_theory=False): + """ + Check satisfiability of a propositional sentence. + Returns a model when it succeeds. + Returns {true: true} for trivially true expressions. + + On setting all_models to True, if given expr is satisfiable then + returns a generator of models. However, if expr is unsatisfiable + then returns a generator containing the single element False. + + Examples + ======== + + >>> from sympy.abc import A, B + >>> from sympy.logic.inference import satisfiable + >>> satisfiable(A & ~B) + {A: True, B: False} + >>> satisfiable(A & ~A) + False + >>> satisfiable(True) + {True: True} + >>> next(satisfiable(A & ~A, all_models=True)) + False + >>> models = satisfiable((A >> B) & B, all_models=True) + >>> next(models) + {A: False, B: True} + >>> next(models) + {A: True, B: True} + >>> def use_models(models): + ... for model in models: + ... if model: + ... # Do something with the model. + ... print(model) + ... else: + ... # Given expr is unsatisfiable. + ... print("UNSAT") + >>> use_models(satisfiable(A >> ~A, all_models=True)) + {A: False} + >>> use_models(satisfiable(A ^ A, all_models=True)) + UNSAT + + """ + if use_lra_theory: + if algorithm is not None and algorithm != "dpll2": + raise ValueError(f"Currently only dpll2 can handle using lra theory. {algorithm} is not handled.") + algorithm = "dpll2" + + if algorithm is None or algorithm == "pycosat": + pycosat = import_module('pycosat') + if pycosat is not None: + algorithm = "pycosat" + else: + if algorithm == "pycosat": + raise ImportError("pycosat module is not present") + # Silently fall back to dpll2 if pycosat + # is not installed + algorithm = "dpll2" + + if algorithm=="minisat22": + pysat = import_module('pysat') + if pysat is None: + algorithm = "dpll2" + + if algorithm=="z3": + z3 = import_module('z3') + if z3 is None: + algorithm = "dpll2" + + if algorithm == "dpll": + from sympy.logic.algorithms.dpll import dpll_satisfiable + return dpll_satisfiable(expr) + elif algorithm == "dpll2": + from sympy.logic.algorithms.dpll2 import dpll_satisfiable + return dpll_satisfiable(expr, all_models, use_lra_theory=use_lra_theory) + elif algorithm == "pycosat": + from sympy.logic.algorithms.pycosat_wrapper import pycosat_satisfiable + return pycosat_satisfiable(expr, all_models) + elif algorithm == "minisat22": + from sympy.logic.algorithms.minisat22_wrapper import minisat22_satisfiable + return minisat22_satisfiable(expr, all_models, minimal) + elif algorithm == "z3": + from sympy.logic.algorithms.z3_wrapper import z3_satisfiable + return z3_satisfiable(expr, all_models) + + raise NotImplementedError + + +def valid(expr): + """ + Check validity of a propositional sentence. + A valid propositional sentence is True under every assignment. + + Examples + ======== + + >>> from sympy.abc import A, B + >>> from sympy.logic.inference import valid + >>> valid(A | ~A) + True + >>> valid(A | B) + False + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Validity + + """ + return not satisfiable(Not(expr)) + + +def pl_true(expr, model=None, deep=False): + """ + Returns whether the given assignment is a model or not. + + If the assignment does not specify the value for every proposition, + this may return None to indicate 'not obvious'. + + Parameters + ========== + + model : dict, optional, default: {} + Mapping of symbols to boolean values to indicate assignment. + deep: boolean, optional, default: False + Gives the value of the expression under partial assignments + correctly. May still return None to indicate 'not obvious'. + + + Examples + ======== + + >>> from sympy.abc import A, B + >>> from sympy.logic.inference import pl_true + >>> pl_true( A & B, {A: True, B: True}) + True + >>> pl_true(A & B, {A: False}) + False + >>> pl_true(A & B, {A: True}) + >>> pl_true(A & B, {A: True}, deep=True) + >>> pl_true(A >> (B >> A)) + >>> pl_true(A >> (B >> A), deep=True) + True + >>> pl_true(A & ~A) + >>> pl_true(A & ~A, deep=True) + False + >>> pl_true(A & B & (~A | ~B), {A: True}) + >>> pl_true(A & B & (~A | ~B), {A: True}, deep=True) + False + + """ + + from sympy.core.symbol import Symbol + + boolean = (True, False) + + def _validate(expr): + if isinstance(expr, Symbol) or expr in boolean: + return True + if not isinstance(expr, BooleanFunction): + return False + return all(_validate(arg) for arg in expr.args) + + if expr in boolean: + return expr + expr = sympify(expr) + if not _validate(expr): + raise ValueError("%s is not a valid boolean expression" % expr) + if not model: + model = {} + model = {k: v for k, v in model.items() if v in boolean} + result = expr.subs(model) + if result in boolean: + return bool(result) + if deep: + model = dict.fromkeys(result.atoms(), True) + if pl_true(result, model): + if valid(result): + return True + else: + if not satisfiable(result): + return False + return None + + +def entails(expr, formula_set=None): + """ + Check whether the given expr_set entail an expr. + If formula_set is empty then it returns the validity of expr. + + Examples + ======== + + >>> from sympy.abc import A, B, C + >>> from sympy.logic.inference import entails + >>> entails(A, [A >> B, B >> C]) + False + >>> entails(C, [A >> B, B >> C, A]) + True + >>> entails(A >> B) + False + >>> entails(A >> (B >> A)) + True + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Logical_consequence + + """ + if formula_set: + formula_set = list(formula_set) + else: + formula_set = [] + formula_set.append(Not(expr)) + return not satisfiable(And(*formula_set)) + + +class KB: + """Base class for all knowledge bases""" + def __init__(self, sentence=None): + self.clauses_ = set() + if sentence: + self.tell(sentence) + + def tell(self, sentence): + raise NotImplementedError + + def ask(self, query): + raise NotImplementedError + + def retract(self, sentence): + raise NotImplementedError + + @property + def clauses(self): + return list(ordered(self.clauses_)) + + +class PropKB(KB): + """A KB for Propositional Logic. Inefficient, with no indexing.""" + + def tell(self, sentence): + """Add the sentence's clauses to the KB + + Examples + ======== + + >>> from sympy.logic.inference import PropKB + >>> from sympy.abc import x, y + >>> l = PropKB() + >>> l.clauses + [] + + >>> l.tell(x | y) + >>> l.clauses + [x | y] + + >>> l.tell(y) + >>> l.clauses + [y, x | y] + + """ + for c in conjuncts(to_cnf(sentence)): + self.clauses_.add(c) + + def ask(self, query): + """Checks if the query is true given the set of clauses. + + Examples + ======== + + >>> from sympy.logic.inference import PropKB + >>> from sympy.abc import x, y + >>> l = PropKB() + >>> l.tell(x & ~y) + >>> l.ask(x) + True + >>> l.ask(y) + False + + """ + return entails(query, self.clauses_) + + def retract(self, sentence): + """Remove the sentence's clauses from the KB + + Examples + ======== + + >>> from sympy.logic.inference import PropKB + >>> from sympy.abc import x, y + >>> l = PropKB() + >>> l.clauses + [] + + >>> l.tell(x | y) + >>> l.clauses + [x | y] + + >>> l.retract(x | y) + >>> l.clauses + [] + + """ + for c in conjuncts(to_cnf(sentence)): + self.clauses_.discard(c) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_boolalg.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_boolalg.py new file mode 100644 index 0000000000000000000000000000000000000000..88cdd647fdcc723faee328f71df96030841a3edb --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_boolalg.py @@ -0,0 +1,1367 @@ +from sympy.assumptions.ask import Q +from sympy.assumptions.refine import refine +from sympy.core.numbers import oo +from sympy.core.relational import Equality, Eq, Ne +from sympy.core.singleton import S +from sympy.core.symbol import (Dummy, symbols) +from sympy.functions import Piecewise +from sympy.functions.elementary.trigonometric import cos, sin +from sympy.sets.sets import Interval, Union +from sympy.sets.contains import Contains +from sympy.simplify.simplify import simplify +from sympy.logic.boolalg import ( + And, Boolean, Equivalent, ITE, Implies, Nand, Nor, Not, Or, + POSform, SOPform, Xor, Xnor, conjuncts, disjuncts, + distribute_or_over_and, distribute_and_over_or, + eliminate_implications, is_nnf, is_cnf, is_dnf, simplify_logic, + to_nnf, to_cnf, to_dnf, to_int_repr, bool_map, true, false, + BooleanAtom, is_literal, term_to_integer, + truth_table, as_Boolean, to_anf, is_anf, distribute_xor_over_and, + anf_coeffs, ANFform, bool_minterm, bool_maxterm, bool_monomial, + _check_pair, _convert_to_varsSOP, _convert_to_varsPOS, Exclusive, + gateinputcount) +from sympy.assumptions.cnf import CNF + +from sympy.testing.pytest import raises, XFAIL, slow + +from itertools import combinations, permutations, product + +A, B, C, D = symbols('A:D') +a, b, c, d, e, w, x, y, z = symbols('a:e w:z') + + +def test_overloading(): + """Test that |, & are overloaded as expected""" + + assert A & B == And(A, B) + assert A | B == Or(A, B) + assert (A & B) | C == Or(And(A, B), C) + assert A >> B == Implies(A, B) + assert A << B == Implies(B, A) + assert ~A == Not(A) + assert A ^ B == Xor(A, B) + + +def test_And(): + assert And() is true + assert And(A) == A + assert And(True) is true + assert And(False) is false + assert And(True, True) is true + assert And(True, False) is false + assert And(False, False) is false + assert And(True, A) == A + assert And(False, A) is false + assert And(True, True, True) is true + assert And(True, True, A) == A + assert And(True, False, A) is false + assert And(1, A) == A + raises(TypeError, lambda: And(2, A)) + assert And(A < 1, A >= 1) is false + e = A > 1 + assert And(e, e.canonical) == e.canonical + g, l, ge, le = A > B, B < A, A >= B, B <= A + assert And(g, l, ge, le) == And(ge, g) + assert {And(*i) for i in permutations((l, g, le, ge))} == {And(ge, g)} + assert And(And(Eq(a, 0), Eq(b, 0)), And(Ne(a, 0), Eq(c, 0))) is false + + +def test_Or(): + assert Or() is false + assert Or(A) == A + assert Or(True) is true + assert Or(False) is false + assert Or(True, True) is true + assert Or(True, False) is true + assert Or(False, False) is false + assert Or(True, A) is true + assert Or(False, A) == A + assert Or(True, False, False) is true + assert Or(True, False, A) is true + assert Or(False, False, A) == A + assert Or(1, A) is true + raises(TypeError, lambda: Or(2, A)) + assert Or(A < 1, A >= 1) is true + e = A > 1 + assert Or(e, e.canonical) == e + g, l, ge, le = A > B, B < A, A >= B, B <= A + assert Or(g, l, ge, le) == Or(g, ge) + + +def test_Xor(): + assert Xor() is false + assert Xor(A) == A + assert Xor(A, A) is false + assert Xor(True, A, A) is true + assert Xor(A, A, A, A, A) == A + assert Xor(True, False, False, A, B) == ~Xor(A, B) + assert Xor(True) is true + assert Xor(False) is false + assert Xor(True, True) is false + assert Xor(True, False) is true + assert Xor(False, False) is false + assert Xor(True, A) == ~A + assert Xor(False, A) == A + assert Xor(True, False, False) is true + assert Xor(True, False, A) == ~A + assert Xor(False, False, A) == A + assert isinstance(Xor(A, B), Xor) + assert Xor(A, B, Xor(C, D)) == Xor(A, B, C, D) + assert Xor(A, B, Xor(B, C)) == Xor(A, C) + assert Xor(A < 1, A >= 1, B) == Xor(0, 1, B) == Xor(1, 0, B) + e = A > 1 + assert Xor(e, e.canonical) == Xor(0, 0) == Xor(1, 1) + + +def test_rewrite_as_And(): + expr = x ^ y + assert expr.rewrite(And) == (x | y) & (~x | ~y) + + +def test_rewrite_as_Or(): + expr = x ^ y + assert expr.rewrite(Or) == (x & ~y) | (y & ~x) + + +def test_rewrite_as_Nand(): + expr = (y & z) | (z & ~w) + assert expr.rewrite(Nand) == ~(~(y & z) & ~(z & ~w)) + + +def test_rewrite_as_Nor(): + expr = z & (y | ~w) + assert expr.rewrite(Nor) == ~(~z | ~(y | ~w)) + + +def test_Not(): + raises(TypeError, lambda: Not(True, False)) + assert Not(True) is false + assert Not(False) is true + assert Not(0) is true + assert Not(1) is false + assert Not(2) is false + + +def test_Nand(): + assert Nand() is false + assert Nand(A) == ~A + assert Nand(True) is false + assert Nand(False) is true + assert Nand(True, True) is false + assert Nand(True, False) is true + assert Nand(False, False) is true + assert Nand(True, A) == ~A + assert Nand(False, A) is true + assert Nand(True, True, True) is false + assert Nand(True, True, A) == ~A + assert Nand(True, False, A) is true + + +def test_Nor(): + assert Nor() is true + assert Nor(A) == ~A + assert Nor(True) is false + assert Nor(False) is true + assert Nor(True, True) is false + assert Nor(True, False) is false + assert Nor(False, False) is true + assert Nor(True, A) is false + assert Nor(False, A) == ~A + assert Nor(True, True, True) is false + assert Nor(True, True, A) is false + assert Nor(True, False, A) is false + + +def test_Xnor(): + assert Xnor() is true + assert Xnor(A) == ~A + assert Xnor(A, A) is true + assert Xnor(True, A, A) is false + assert Xnor(A, A, A, A, A) == ~A + assert Xnor(True) is false + assert Xnor(False) is true + assert Xnor(True, True) is true + assert Xnor(True, False) is false + assert Xnor(False, False) is true + assert Xnor(True, A) == A + assert Xnor(False, A) == ~A + assert Xnor(True, False, False) is false + assert Xnor(True, False, A) == A + assert Xnor(False, False, A) == ~A + + +def test_Implies(): + raises(ValueError, lambda: Implies(A, B, C)) + assert Implies(True, True) is true + assert Implies(True, False) is false + assert Implies(False, True) is true + assert Implies(False, False) is true + assert Implies(0, A) is true + assert Implies(1, 1) is true + assert Implies(1, 0) is false + assert A >> B == B << A + assert (A < 1) >> (A >= 1) == (A >= 1) + assert (A < 1) >> (S.One > A) is true + assert A >> A is true + + +def test_Equivalent(): + assert Equivalent(A, B) == Equivalent(B, A) == Equivalent(A, B, A) + assert Equivalent() is true + assert Equivalent(A, A) == Equivalent(A) is true + assert Equivalent(True, True) == Equivalent(False, False) is true + assert Equivalent(True, False) == Equivalent(False, True) is false + assert Equivalent(A, True) == A + assert Equivalent(A, False) == Not(A) + assert Equivalent(A, B, True) == A & B + assert Equivalent(A, B, False) == ~A & ~B + assert Equivalent(1, A) == A + assert Equivalent(0, A) == Not(A) + assert Equivalent(A, Equivalent(B, C)) != Equivalent(Equivalent(A, B), C) + assert Equivalent(A < 1, A >= 1) is false + assert Equivalent(A < 1, A >= 1, 0) is false + assert Equivalent(A < 1, A >= 1, 1) is false + assert Equivalent(A < 1, S.One > A) == Equivalent(1, 1) == Equivalent(0, 0) + assert Equivalent(Equality(A, B), Equality(B, A)) is true + + +def test_Exclusive(): + assert Exclusive(False, False, False) is true + assert Exclusive(True, False, False) is true + assert Exclusive(True, True, False) is false + assert Exclusive(True, True, True) is false + + +def test_equals(): + assert Not(Or(A, B)).equals(And(Not(A), Not(B))) is True + assert Equivalent(A, B).equals((A >> B) & (B >> A)) is True + assert ((A | ~B) & (~A | B)).equals((~A & ~B) | (A & B)) is True + assert (A >> B).equals(~A >> ~B) is False + assert (A >> (B >> A)).equals(A >> (C >> A)) is False + raises(NotImplementedError, lambda: (A & B).equals(A > B)) + + +def test_simplification_boolalg(): + """ + Test working of simplification methods. + """ + set1 = [[0, 0, 1], [0, 1, 1], [1, 0, 0], [1, 1, 0]] + set2 = [[0, 0, 0], [0, 1, 0], [1, 0, 1], [1, 1, 1]] + assert SOPform([x, y, z], set1) == Or(And(Not(x), z), And(Not(z), x)) + assert Not(SOPform([x, y, z], set2)) == \ + Not(Or(And(Not(x), Not(z)), And(x, z))) + assert POSform([x, y, z], set1 + set2) is true + assert SOPform([x, y, z], set1 + set2) is true + assert SOPform([Dummy(), Dummy(), Dummy()], set1 + set2) is true + + minterms = [[0, 0, 0, 1], [0, 0, 1, 1], [0, 1, 1, 1], [1, 0, 1, 1], + [1, 1, 1, 1]] + dontcares = [[0, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 1]] + assert ( + SOPform([w, x, y, z], minterms, dontcares) == + Or(And(y, z), And(Not(w), Not(x)))) + assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z) + + minterms = [1, 3, 7, 11, 15] + dontcares = [0, 2, 5] + assert ( + SOPform([w, x, y, z], minterms, dontcares) == + Or(And(y, z), And(Not(w), Not(x)))) + assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z) + + minterms = [1, [0, 0, 1, 1], 7, [1, 0, 1, 1], + [1, 1, 1, 1]] + dontcares = [0, [0, 0, 1, 0], 5] + assert ( + SOPform([w, x, y, z], minterms, dontcares) == + Or(And(y, z), And(Not(w), Not(x)))) + assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z) + + minterms = [1, {y: 1, z: 1}] + dontcares = [0, [0, 0, 1, 0], 5] + assert ( + SOPform([w, x, y, z], minterms, dontcares) == + Or(And(y, z), And(Not(w), Not(x)))) + assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z) + + minterms = [{y: 1, z: 1}, 1] + dontcares = [[0, 0, 0, 0]] + + minterms = [[0, 0, 0]] + raises(ValueError, lambda: SOPform([w, x, y, z], minterms)) + raises(ValueError, lambda: POSform([w, x, y, z], minterms)) + + raises(TypeError, lambda: POSform([w, x, y, z], ["abcdefg"])) + + # test simplification + ans = And(A, Or(B, C)) + assert simplify_logic(A & (B | C)) == ans + assert simplify_logic((A & B) | (A & C)) == ans + assert simplify_logic(Implies(A, B)) == Or(Not(A), B) + assert simplify_logic(Equivalent(A, B)) == \ + Or(And(A, B), And(Not(A), Not(B))) + assert simplify_logic(And(Equality(A, 2), C)) == And(Equality(A, 2), C) + assert simplify_logic(And(Equality(A, 2), A)) == And(Equality(A, 2), A) + assert simplify_logic(And(Equality(A, B), C)) == And(Equality(A, B), C) + assert simplify_logic(Or(And(Equality(A, 3), B), And(Equality(A, 3), C))) \ + == And(Equality(A, 3), Or(B, C)) + b = (~x & ~y & ~z) | (~x & ~y & z) + e = And(A, b) + assert simplify_logic(e) == A & ~x & ~y + raises(ValueError, lambda: simplify_logic(A & (B | C), form='blabla')) + assert simplify(Or(x <= y, And(x < y, z))) == (x <= y) + assert simplify(Or(x <= y, And(y > x, z))) == (x <= y) + assert simplify(Or(x >= y, And(y < x, z))) == (x >= y) + + # Check that expressions with nine variables or more are not simplified + # (without the force-flag) + a, b, c, d, e, f, g, h, j = symbols('a b c d e f g h j') + expr = a & b & c & d & e & f & g & h & j | \ + a & b & c & d & e & f & g & h & ~j + # This expression can be simplified to get rid of the j variables + assert simplify_logic(expr) == expr + + # Test dontcare + assert simplify_logic((a & b) | c | d, dontcare=(a & b)) == c | d + + # check input + ans = SOPform([x, y], [[1, 0]]) + assert SOPform([x, y], [[1, 0]]) == ans + assert POSform([x, y], [[1, 0]]) == ans + + raises(ValueError, lambda: SOPform([x], [[1]], [[1]])) + assert SOPform([x], [[1]], [[0]]) is true + assert SOPform([x], [[0]], [[1]]) is true + assert SOPform([x], [], []) is false + + raises(ValueError, lambda: POSform([x], [[1]], [[1]])) + assert POSform([x], [[1]], [[0]]) is true + assert POSform([x], [[0]], [[1]]) is true + assert POSform([x], [], []) is false + + # check working of simplify + assert simplify((A & B) | (A & C)) == And(A, Or(B, C)) + assert simplify(And(x, Not(x))) == False + assert simplify(Or(x, Not(x))) == True + assert simplify(And(Eq(x, 0), Eq(x, y))) == And(Eq(x, 0), Eq(y, 0)) + assert And(Eq(x - 1, 0), Eq(x, y)).simplify() == And(Eq(x, 1), Eq(y, 1)) + assert And(Ne(x - 1, 0), Ne(x, y)).simplify() == And(Ne(x, 1), Ne(x, y)) + assert And(Eq(x - 1, 0), Ne(x, y)).simplify() == And(Eq(x, 1), Ne(y, 1)) + assert And(Eq(x - 1, 0), Eq(x, z + y), Eq(y + x, 0)).simplify( + ) == And(Eq(x, 1), Eq(y, -1), Eq(z, 2)) + assert And(Eq(x - 1, 0), Eq(x + 2, 3)).simplify() == Eq(x, 1) + assert And(Ne(x - 1, 0), Ne(x + 2, 3)).simplify() == Ne(x, 1) + assert And(Eq(x - 1, 0), Eq(x + 2, 2)).simplify() == False + assert And(Ne(x - 1, 0), Ne(x + 2, 2)).simplify( + ) == And(Ne(x, 1), Ne(x, 0)) + assert simplify(Xor(x, ~x)) == True + + +def test_bool_map(): + """ + Test working of bool_map function. + """ + + minterms = [[0, 0, 0, 1], [0, 0, 1, 1], [0, 1, 1, 1], [1, 0, 1, 1], + [1, 1, 1, 1]] + assert bool_map(Not(Not(a)), a) == (a, {a: a}) + assert bool_map(SOPform([w, x, y, z], minterms), + POSform([w, x, y, z], minterms)) == \ + (And(Or(Not(w), y), Or(Not(x), y), z), {x: x, w: w, z: z, y: y}) + assert bool_map(SOPform([x, z, y], [[1, 0, 1]]), + SOPform([a, b, c], [[1, 0, 1]])) != False + function1 = SOPform([x, z, y], [[1, 0, 1], [0, 0, 1]]) + function2 = SOPform([a, b, c], [[1, 0, 1], [1, 0, 0]]) + assert bool_map(function1, function2) == \ + (function1, {y: a, z: b}) + assert bool_map(Xor(x, y), ~Xor(x, y)) == False + assert bool_map(And(x, y), Or(x, y)) is None + assert bool_map(And(x, y), And(x, y, z)) is None + # issue 16179 + assert bool_map(Xor(x, y, z), ~Xor(x, y, z)) == False + assert bool_map(Xor(a, x, y, z), ~Xor(a, x, y, z)) == False + + +def test_bool_symbol(): + """Test that mixing symbols with boolean values + works as expected""" + + assert And(A, True) == A + assert And(A, True, True) == A + assert And(A, False) is false + assert And(A, True, False) is false + assert Or(A, True) is true + assert Or(A, False) == A + + +def test_is_boolean(): + assert isinstance(True, Boolean) is False + assert isinstance(true, Boolean) is True + assert 1 == True + assert 1 != true + assert (1 == true) is False + assert 0 == False + assert 0 != false + assert (0 == false) is False + assert true.is_Boolean is True + assert (A & B).is_Boolean + assert (A | B).is_Boolean + assert (~A).is_Boolean + assert (A ^ B).is_Boolean + assert A.is_Boolean != isinstance(A, Boolean) + assert isinstance(A, Boolean) + + +def test_subs(): + assert (A & B).subs(A, True) == B + assert (A & B).subs(A, False) is false + assert (A & B).subs(B, True) == A + assert (A & B).subs(B, False) is false + assert (A & B).subs({A: True, B: True}) is true + assert (A | B).subs(A, True) is true + assert (A | B).subs(A, False) == B + assert (A | B).subs(B, True) is true + assert (A | B).subs(B, False) == A + assert (A | B).subs({A: True, B: True}) is true + + +""" +we test for axioms of boolean algebra +see https://en.wikipedia.org/wiki/Boolean_algebra_(structure) +""" + + +def test_commutative(): + """Test for commutativity of And and Or""" + A, B = map(Boolean, symbols('A,B')) + + assert A & B == B & A + assert A | B == B | A + + +def test_and_associativity(): + """Test for associativity of And""" + + assert (A & B) & C == A & (B & C) + + +def test_or_assicativity(): + assert ((A | B) | C) == (A | (B | C)) + + +def test_double_negation(): + a = Boolean() + assert ~(~a) == a + + +# test methods + +def test_eliminate_implications(): + assert eliminate_implications(Implies(A, B, evaluate=False)) == (~A) | B + assert eliminate_implications( + A >> (C >> Not(B))) == Or(Or(Not(B), Not(C)), Not(A)) + assert eliminate_implications(Equivalent(A, B, C, D)) == \ + (~A | B) & (~B | C) & (~C | D) & (~D | A) + + +def test_conjuncts(): + assert conjuncts(A & B & C) == {A, B, C} + assert conjuncts((A | B) & C) == {A | B, C} + assert conjuncts(A) == {A} + assert conjuncts(True) == {True} + assert conjuncts(False) == {False} + + +def test_disjuncts(): + assert disjuncts(A | B | C) == {A, B, C} + assert disjuncts((A | B) & C) == {(A | B) & C} + assert disjuncts(A) == {A} + assert disjuncts(True) == {True} + assert disjuncts(False) == {False} + + +def test_distribute(): + assert distribute_and_over_or(Or(And(A, B), C)) == And(Or(A, C), Or(B, C)) + assert distribute_or_over_and(And(A, Or(B, C))) == Or(And(A, B), And(A, C)) + assert distribute_xor_over_and(And(A, Xor(B, C))) == Xor(And(A, B), And(A, C)) + + +def test_to_anf(): + x, y, z = symbols('x,y,z') + assert to_anf(And(x, y)) == And(x, y) + assert to_anf(Or(x, y)) == Xor(x, y, And(x, y)) + assert to_anf(Or(Implies(x, y), And(x, y), y)) == \ + Xor(x, True, x & y, remove_true=False) + assert to_anf(Or(Nand(x, y), Nor(x, y), Xnor(x, y), Implies(x, y))) == True + assert to_anf(Or(x, Not(y), Nor(x, z), And(x, y), Nand(y, z))) == \ + Xor(True, And(y, z), And(x, y, z), remove_true=False) + assert to_anf(Xor(x, y)) == Xor(x, y) + assert to_anf(Not(x)) == Xor(x, True, remove_true=False) + assert to_anf(Nand(x, y)) == Xor(True, And(x, y), remove_true=False) + assert to_anf(Nor(x, y)) == Xor(x, y, True, And(x, y), remove_true=False) + assert to_anf(Implies(x, y)) == Xor(x, True, And(x, y), remove_true=False) + assert to_anf(Equivalent(x, y)) == Xor(x, y, True, remove_true=False) + assert to_anf(Nand(x | y, x >> y), deep=False) == \ + Xor(True, And(Or(x, y), Implies(x, y)), remove_true=False) + assert to_anf(Nor(x ^ y, x & y), deep=False) == \ + Xor(True, Or(Xor(x, y), And(x, y)), remove_true=False) + # issue 25218 + assert to_anf(x ^ ~(x ^ y ^ ~y)) == False + + +def test_to_nnf(): + assert to_nnf(true) is true + assert to_nnf(false) is false + assert to_nnf(A) == A + assert to_nnf(A | ~A | B) is true + assert to_nnf(A & ~A & B) is false + assert to_nnf(A >> B) == ~A | B + assert to_nnf(Equivalent(A, B, C)) == (~A | B) & (~B | C) & (~C | A) + assert to_nnf(A ^ B ^ C) == \ + (A | B | C) & (~A | ~B | C) & (A | ~B | ~C) & (~A | B | ~C) + assert to_nnf(ITE(A, B, C)) == (~A | B) & (A | C) + assert to_nnf(Not(A | B | C)) == ~A & ~B & ~C + assert to_nnf(Not(A & B & C)) == ~A | ~B | ~C + assert to_nnf(Not(A >> B)) == A & ~B + assert to_nnf(Not(Equivalent(A, B, C))) == And(Or(A, B, C), Or(~A, ~B, ~C)) + assert to_nnf(Not(A ^ B ^ C)) == \ + (~A | B | C) & (A | ~B | C) & (A | B | ~C) & (~A | ~B | ~C) + assert to_nnf(Not(ITE(A, B, C))) == (~A | ~B) & (A | ~C) + assert to_nnf((A >> B) ^ (B >> A)) == (A & ~B) | (~A & B) + assert to_nnf((A >> B) ^ (B >> A), False) == \ + (~A | ~B | A | B) & ((A & ~B) | (~A & B)) + assert ITE(A, 1, 0).to_nnf() == A + assert ITE(A, 0, 1).to_nnf() == ~A + # although ITE can hold non-Boolean, it will complain if + # an attempt is made to convert the ITE to Boolean nnf + raises(TypeError, lambda: ITE(A < 1, [1], B).to_nnf()) + + +def test_to_cnf(): + assert to_cnf(~(B | C)) == And(Not(B), Not(C)) + assert to_cnf((A & B) | C) == And(Or(A, C), Or(B, C)) + assert to_cnf(A >> B) == (~A) | B + assert to_cnf(A >> (B & C)) == (~A | B) & (~A | C) + assert to_cnf(A & (B | C) | ~A & (B | C), True) == B | C + assert to_cnf(A & B) == And(A, B) + + assert to_cnf(Equivalent(A, B)) == And(Or(A, Not(B)), Or(B, Not(A))) + assert to_cnf(Equivalent(A, B & C)) == \ + (~A | B) & (~A | C) & (~B | ~C | A) + assert to_cnf(Equivalent(A, B | C), True) == \ + And(Or(Not(B), A), Or(Not(C), A), Or(B, C, Not(A))) + assert to_cnf(A + 1) == A + 1 + + +def test_issue_18904(): + x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15 = symbols('x1:16') + eq = ((x1 & x2 & x3 & x4 & x5 & x6 & x7 & x8 & x9) | + (x1 & x2 & x3 & x4 & x5 & x6 & x7 & x10 & x9) | + (x1 & x11 & x3 & x12 & x5 & x13 & x14 & x15 & x9)) + assert is_cnf(to_cnf(eq)) + raises(ValueError, lambda: to_cnf(eq, simplify=True)) + for f, t in zip((And, Or), (to_cnf, to_dnf)): + eq = f(x1, x2, x3, x4, x5, x6, x7, x8, x9) + raises(ValueError, lambda: to_cnf(eq, simplify=True)) + assert t(eq, simplify=True, force=True) == eq + + +def test_issue_9949(): + assert is_cnf(to_cnf((b > -5) | (a > 2) & (a < 4))) + + +def test_to_CNF(): + assert CNF.CNF_to_cnf(CNF.to_CNF(~(B | C))) == to_cnf(~(B | C)) + assert CNF.CNF_to_cnf(CNF.to_CNF((A & B) | C)) == to_cnf((A & B) | C) + assert CNF.CNF_to_cnf(CNF.to_CNF(A >> B)) == to_cnf(A >> B) + assert CNF.CNF_to_cnf(CNF.to_CNF(A >> (B & C))) == to_cnf(A >> (B & C)) + assert CNF.CNF_to_cnf(CNF.to_CNF(A & (B | C) | ~A & (B | C))) == to_cnf(A & (B | C) | ~A & (B | C)) + assert CNF.CNF_to_cnf(CNF.to_CNF(A & B)) == to_cnf(A & B) + + +def test_to_dnf(): + assert to_dnf(~(B | C)) == And(Not(B), Not(C)) + assert to_dnf(A & (B | C)) == Or(And(A, B), And(A, C)) + assert to_dnf(A >> B) == (~A) | B + assert to_dnf(A >> (B & C)) == (~A) | (B & C) + assert to_dnf(A | B) == A | B + + assert to_dnf(Equivalent(A, B), True) == \ + Or(And(A, B), And(Not(A), Not(B))) + assert to_dnf(Equivalent(A, B & C), True) == \ + Or(And(A, B, C), And(Not(A), Not(B)), And(Not(A), Not(C))) + assert to_dnf(A + 1) == A + 1 + + +def test_to_int_repr(): + x, y, z = map(Boolean, symbols('x,y,z')) + + def sorted_recursive(arg): + try: + return sorted(sorted_recursive(x) for x in arg) + except TypeError: # arg is not a sequence + return arg + + assert sorted_recursive(to_int_repr([x | y, z | x], [x, y, z])) == \ + sorted_recursive([[1, 2], [1, 3]]) + assert sorted_recursive(to_int_repr([x | y, z | ~x], [x, y, z])) == \ + sorted_recursive([[1, 2], [3, -1]]) + + +def test_is_anf(): + x, y = symbols('x,y') + assert is_anf(true) is True + assert is_anf(false) is True + assert is_anf(x) is True + assert is_anf(And(x, y)) is True + assert is_anf(Xor(x, y, And(x, y))) is True + assert is_anf(Xor(x, y, Or(x, y))) is False + assert is_anf(Xor(Not(x), y)) is False + + +def test_is_nnf(): + assert is_nnf(true) is True + assert is_nnf(A) is True + assert is_nnf(~A) is True + assert is_nnf(A & B) is True + assert is_nnf((A & B) | (~A & A) | (~B & B) | (~A & ~B), False) is True + assert is_nnf((A | B) & (~A | ~B)) is True + assert is_nnf(Not(Or(A, B))) is False + assert is_nnf(A ^ B) is False + assert is_nnf((A & B) | (~A & A) | (~B & B) | (~A & ~B), True) is False + + +def test_is_cnf(): + assert is_cnf(x) is True + assert is_cnf(x | y | z) is True + assert is_cnf(x & y & z) is True + assert is_cnf((x | y) & z) is True + assert is_cnf((x & y) | z) is False + assert is_cnf(~(x & y) | z) is False + + +def test_is_dnf(): + assert is_dnf(x) is True + assert is_dnf(x | y | z) is True + assert is_dnf(x & y & z) is True + assert is_dnf((x & y) | z) is True + assert is_dnf((x | y) & z) is False + assert is_dnf(~(x | y) & z) is False + + +def test_ITE(): + A, B, C = symbols('A:C') + assert ITE(True, False, True) is false + assert ITE(True, True, False) is true + assert ITE(False, True, False) is false + assert ITE(False, False, True) is true + assert isinstance(ITE(A, B, C), ITE) + + A = True + assert ITE(A, B, C) == B + A = False + assert ITE(A, B, C) == C + B = True + assert ITE(And(A, B), B, C) == C + assert ITE(Or(A, False), And(B, True), False) is false + assert ITE(x, A, B) == Not(x) + assert ITE(x, B, A) == x + assert ITE(1, x, y) == x + assert ITE(0, x, y) == y + raises(TypeError, lambda: ITE(2, x, y)) + raises(TypeError, lambda: ITE(1, [], y)) + raises(TypeError, lambda: ITE(1, (), y)) + raises(TypeError, lambda: ITE(1, y, [])) + assert ITE(1, 1, 1) is S.true + assert isinstance(ITE(1, 1, 1, evaluate=False), ITE) + + assert ITE(Eq(x, True), y, x) == ITE(x, y, x) + assert ITE(Eq(x, False), y, x) == ITE(~x, y, x) + assert ITE(Ne(x, True), y, x) == ITE(~x, y, x) + assert ITE(Ne(x, False), y, x) == ITE(x, y, x) + assert ITE(Eq(S.true, x), y, x) == ITE(x, y, x) + assert ITE(Eq(S.false, x), y, x) == ITE(~x, y, x) + assert ITE(Ne(S.true, x), y, x) == ITE(~x, y, x) + assert ITE(Ne(S.false, x), y, x) == ITE(x, y, x) + # 0 and 1 in the context are not treated as True/False + # so the equality must always be False since dissimilar + # objects cannot be equal + assert ITE(Eq(x, 0), y, x) == x + assert ITE(Eq(x, 1), y, x) == x + assert ITE(Ne(x, 0), y, x) == y + assert ITE(Ne(x, 1), y, x) == y + assert ITE(Eq(x, 0), y, z).subs(x, 0) == y + assert ITE(Eq(x, 0), y, z).subs(x, 1) == z + raises(ValueError, lambda: ITE(x > 1, y, x, z)) + + +def test_is_literal(): + assert is_literal(True) is True + assert is_literal(False) is True + assert is_literal(A) is True + assert is_literal(~A) is True + assert is_literal(Or(A, B)) is False + assert is_literal(Q.zero(A)) is True + assert is_literal(Not(Q.zero(A))) is True + assert is_literal(Or(A, B)) is False + assert is_literal(And(Q.zero(A), Q.zero(B))) is False + assert is_literal(x < 3) + assert not is_literal(x + y < 3) + + +def test_operators(): + # Mostly test __and__, __rand__, and so on + assert True & A == A & True == A + assert False & A == A & False == False + assert A & B == And(A, B) + assert True | A == A | True == True + assert False | A == A | False == A + assert A | B == Or(A, B) + assert ~A == Not(A) + assert True >> A == A << True == A + assert False >> A == A << False == True + assert A >> True == True << A == True + assert A >> False == False << A == ~A + assert A >> B == B << A == Implies(A, B) + assert True ^ A == A ^ True == ~A + assert False ^ A == A ^ False == A + assert A ^ B == Xor(A, B) + + +def test_true_false(): + assert true is S.true + assert false is S.false + assert true is not True + assert false is not False + assert true + assert not false + assert true == True + assert false == False + assert not (true == False) + assert not (false == True) + assert not (true == false) + + assert hash(true) == hash(True) + assert hash(false) == hash(False) + assert len({true, True}) == len({false, False}) == 1 + + assert isinstance(true, BooleanAtom) + assert isinstance(false, BooleanAtom) + # We don't want to subclass from bool, because bool subclasses from + # int. But operators like &, |, ^, <<, >>, and ~ act differently on 0 and + # 1 then we want them to on true and false. See the docstrings of the + # various And, Or, etc. functions for examples. + assert not isinstance(true, bool) + assert not isinstance(false, bool) + + # Note: using 'is' comparison is important here. We want these to return + # true and false, not True and False + + assert Not(true) is false + assert Not(True) is false + assert Not(false) is true + assert Not(False) is true + assert ~true is false + assert ~false is true + + for T, F in product((True, true), (False, false)): + assert And(T, F) is false + assert And(F, T) is false + assert And(F, F) is false + assert And(T, T) is true + assert And(T, x) == x + assert And(F, x) is false + if not (T is True and F is False): + assert T & F is false + assert F & T is false + if F is not False: + assert F & F is false + if T is not True: + assert T & T is true + + assert Or(T, F) is true + assert Or(F, T) is true + assert Or(F, F) is false + assert Or(T, T) is true + assert Or(T, x) is true + assert Or(F, x) == x + if not (T is True and F is False): + assert T | F is true + assert F | T is true + if F is not False: + assert F | F is false + if T is not True: + assert T | T is true + + assert Xor(T, F) is true + assert Xor(F, T) is true + assert Xor(F, F) is false + assert Xor(T, T) is false + assert Xor(T, x) == ~x + assert Xor(F, x) == x + if not (T is True and F is False): + assert T ^ F is true + assert F ^ T is true + if F is not False: + assert F ^ F is false + if T is not True: + assert T ^ T is false + + assert Nand(T, F) is true + assert Nand(F, T) is true + assert Nand(F, F) is true + assert Nand(T, T) is false + assert Nand(T, x) == ~x + assert Nand(F, x) is true + + assert Nor(T, F) is false + assert Nor(F, T) is false + assert Nor(F, F) is true + assert Nor(T, T) is false + assert Nor(T, x) is false + assert Nor(F, x) == ~x + + assert Implies(T, F) is false + assert Implies(F, T) is true + assert Implies(F, F) is true + assert Implies(T, T) is true + assert Implies(T, x) == x + assert Implies(F, x) is true + assert Implies(x, T) is true + assert Implies(x, F) == ~x + if not (T is True and F is False): + assert T >> F is false + assert F << T is false + assert F >> T is true + assert T << F is true + if F is not False: + assert F >> F is true + assert F << F is true + if T is not True: + assert T >> T is true + assert T << T is true + + assert Equivalent(T, F) is false + assert Equivalent(F, T) is false + assert Equivalent(F, F) is true + assert Equivalent(T, T) is true + assert Equivalent(T, x) == x + assert Equivalent(F, x) == ~x + assert Equivalent(x, T) == x + assert Equivalent(x, F) == ~x + + assert ITE(T, T, T) is true + assert ITE(T, T, F) is true + assert ITE(T, F, T) is false + assert ITE(T, F, F) is false + assert ITE(F, T, T) is true + assert ITE(F, T, F) is false + assert ITE(F, F, T) is true + assert ITE(F, F, F) is false + + assert all(i.simplify(1, 2) is i for i in (S.true, S.false)) + + +def test_bool_as_set(): + assert ITE(y <= 0, False, y >= 1).as_set() == Interval(1, oo) + assert And(x <= 2, x >= -2).as_set() == Interval(-2, 2) + assert Or(x >= 2, x <= -2).as_set() == Interval(-oo, -2) + Interval(2, oo) + assert Not(x > 2).as_set() == Interval(-oo, 2) + # issue 10240 + assert Not(And(x > 2, x < 3)).as_set() == \ + Union(Interval(-oo, 2), Interval(3, oo)) + assert true.as_set() == S.UniversalSet + assert false.as_set() is S.EmptySet + assert x.as_set() == S.UniversalSet + assert And(Or(x < 1, x > 3), x < 2).as_set() == Interval.open(-oo, 1) + assert And(x < 1, sin(x) < 3).as_set() == (x < 1).as_set() + raises(NotImplementedError, lambda: (sin(x) < 1).as_set()) + # watch for object morph in as_set + assert Eq(-1, cos(2 * x) ** 2 / sin(2 * x) ** 2).as_set() is S.EmptySet + + +@XFAIL +def test_multivariate_bool_as_set(): + x, y = symbols('x,y') + + assert And(x >= 0, y >= 0).as_set() == Interval(0, oo) * Interval(0, oo) + assert Or(x >= 0, y >= 0).as_set() == S.Reals * S.Reals - \ + Interval(-oo, 0, True, True) * Interval(-oo, 0, True, True) + + +def test_all_or_nothing(): + x = symbols('x', extended_real=True) + args = x >= -oo, x <= oo + v = And(*args) + if v.func is And: + assert len(v.args) == len(args) - args.count(S.true) + else: + assert v == True + v = Or(*args) + if v.func is Or: + assert len(v.args) == 2 + else: + assert v == True + + +def test_canonical_atoms(): + assert true.canonical == true + assert false.canonical == false + + +def test_negated_atoms(): + assert true.negated == false + assert false.negated == true + + +def test_issue_8777(): + assert And(x > 2, x < oo).as_set() == Interval(2, oo, left_open=True) + assert And(x >= 1, x < oo).as_set() == Interval(1, oo) + assert (x < oo).as_set() == Interval(-oo, oo) + assert (x > -oo).as_set() == Interval(-oo, oo) + + +def test_issue_8975(): + assert Or(And(-oo < x, x <= -2), And(2 <= x, x < oo)).as_set() == \ + Interval(-oo, -2) + Interval(2, oo) + + +def test_term_to_integer(): + assert term_to_integer([1, 0, 1, 0, 0, 1, 0]) == 82 + assert term_to_integer('0010101000111001') == 10809 + + +def test_issue_21971(): + a, b, c, d = symbols('a b c d') + f = a & b & c | a & c + assert f.subs(a & c, d) == b & d | d + assert f.subs(a & b & c, d) == a & c | d + + f = (a | b | c) & (a | c) + assert f.subs(a | c, d) == (b | d) & d + assert f.subs(a | b | c, d) == (a | c) & d + + f = (a ^ b ^ c) & (a ^ c) + assert f.subs(a ^ c, d) == (b ^ d) & d + assert f.subs(a ^ b ^ c, d) == (a ^ c) & d + + +def test_truth_table(): + assert list(truth_table(And(x, y), [x, y], input=False)) == \ + [False, False, False, True] + assert list(truth_table(x | y, [x, y], input=False)) == \ + [False, True, True, True] + assert list(truth_table(x >> y, [x, y], input=False)) == \ + [True, True, False, True] + assert list(truth_table(And(x, y), [x, y])) == \ + [([0, 0], False), ([0, 1], False), ([1, 0], False), ([1, 1], True)] + + +def test_issue_8571(): + for t in (S.true, S.false): + raises(TypeError, lambda: +t) + raises(TypeError, lambda: -t) + raises(TypeError, lambda: abs(t)) + # use int(bool(t)) to get 0 or 1 + raises(TypeError, lambda: int(t)) + + for o in [S.Zero, S.One, x]: + for _ in range(2): + raises(TypeError, lambda: o + t) + raises(TypeError, lambda: o - t) + raises(TypeError, lambda: o % t) + raises(TypeError, lambda: o * t) + raises(TypeError, lambda: o / t) + raises(TypeError, lambda: o ** t) + o, t = t, o # do again in reversed order + + +def test_expand_relational(): + n = symbols('n', negative=True) + p, q = symbols('p q', positive=True) + r = ((n + q * (-n / q + 1)) / (q * (-n / q + 1)) < 0) + assert r is not S.false + assert r.expand() is S.false + assert (q > 0).expand() is S.true + + +def test_issue_12717(): + assert S.true.is_Atom == True + assert S.false.is_Atom == True + + +def test_as_Boolean(): + nz = symbols('nz', nonzero=True) + assert all(as_Boolean(i) is S.true for i in (True, S.true, 1, nz)) + z = symbols('z', zero=True) + assert all(as_Boolean(i) is S.false for i in (False, S.false, 0, z)) + assert all(as_Boolean(i) == i for i in (x, x < 0)) + for i in (2, S(2), x + 1, []): + raises(TypeError, lambda: as_Boolean(i)) + + +def test_binary_symbols(): + assert ITE(x < 1, y, z).binary_symbols == {y, z} + for f in (Eq, Ne): + assert f(x, 1).binary_symbols == set() + assert f(x, True).binary_symbols == {x} + assert f(x, False).binary_symbols == {x} + assert S.true.binary_symbols == set() + assert S.false.binary_symbols == set() + assert x.binary_symbols == {x} + assert And(x, Eq(y, False), Eq(z, 1)).binary_symbols == {x, y} + assert Q.prime(x).binary_symbols == set() + assert Q.lt(x, 1).binary_symbols == set() + assert Q.is_true(x).binary_symbols == {x} + assert Q.eq(x, True).binary_symbols == {x} + assert Q.prime(x).binary_symbols == set() + + +def test_BooleanFunction_diff(): + assert And(x, y).diff(x) == Piecewise((0, Eq(y, False)), (1, True)) + + +def test_issue_14700(): + A, B, C, D, E, F, G, H = symbols('A B C D E F G H') + q = ((B & D & H & ~F) | (B & H & ~C & ~D) | (B & H & ~C & ~F) | + (B & H & ~D & ~G) | (B & H & ~F & ~G) | (C & G & ~B & ~D) | + (C & G & ~D & ~H) | (C & G & ~F & ~H) | (D & F & H & ~B) | + (D & F & ~G & ~H) | (B & D & F & ~C & ~H) | (D & E & F & ~B & ~C) | + (D & F & ~A & ~B & ~C) | (D & F & ~A & ~C & ~H) | + (A & B & D & F & ~E & ~H)) + soldnf = ((B & D & H & ~F) | (D & F & H & ~B) | (B & H & ~C & ~D) | + (B & H & ~D & ~G) | (C & G & ~B & ~D) | (C & G & ~D & ~H) | + (C & G & ~F & ~H) | (D & F & ~G & ~H) | (D & E & F & ~C & ~H) | + (D & F & ~A & ~C & ~H) | (A & B & D & F & ~E & ~H)) + solcnf = ((B | C | D) & (B | D | G) & (C | D | H) & (C | F | H) & + (D | G | H) & (F | G | H) & (B | F | ~D | ~H) & + (~B | ~D | ~F | ~H) & (D | ~B | ~C | ~G | ~H) & + (A | H | ~C | ~D | ~F | ~G) & (H | ~C | ~D | ~E | ~F | ~G) & + (B | E | H | ~A | ~D | ~F | ~G)) + assert simplify_logic(q, "dnf") == soldnf + assert simplify_logic(q, "cnf") == solcnf + + minterms = [[0, 1, 0, 0], [0, 1, 0, 1], [0, 1, 1, 0], [0, 1, 1, 1], + [0, 0, 1, 1], [1, 0, 1, 1]] + dontcares = [[1, 0, 0, 0], [1, 0, 0, 1], [1, 1, 0, 0], [1, 1, 0, 1]] + assert SOPform([w, x, y, z], minterms) == (x & ~w) | (y & z & ~x) + # Should not be more complicated with don't cares + assert SOPform([w, x, y, z], minterms, dontcares) == \ + (x & ~w) | (y & z & ~x) + + +def test_issue_25115(): + cond = Contains(x, S.Integers) + # Previously this raised an exception: + assert simplify_logic(cond) == cond + + +def test_relational_simplification(): + w, x, y, z = symbols('w x y z', real=True) + d, e = symbols('d e', real=False) + # Test all combinations or sign and order + assert Or(x >= y, x < y).simplify() == S.true + assert Or(x >= y, y > x).simplify() == S.true + assert Or(x >= y, -x > -y).simplify() == S.true + assert Or(x >= y, -y < -x).simplify() == S.true + assert Or(-x <= -y, x < y).simplify() == S.true + assert Or(-x <= -y, -x > -y).simplify() == S.true + assert Or(-x <= -y, y > x).simplify() == S.true + assert Or(-x <= -y, -y < -x).simplify() == S.true + assert Or(y <= x, x < y).simplify() == S.true + assert Or(y <= x, y > x).simplify() == S.true + assert Or(y <= x, -x > -y).simplify() == S.true + assert Or(y <= x, -y < -x).simplify() == S.true + assert Or(-y >= -x, x < y).simplify() == S.true + assert Or(-y >= -x, y > x).simplify() == S.true + assert Or(-y >= -x, -x > -y).simplify() == S.true + assert Or(-y >= -x, -y < -x).simplify() == S.true + + assert Or(x < y, x >= y).simplify() == S.true + assert Or(y > x, x >= y).simplify() == S.true + assert Or(-x > -y, x >= y).simplify() == S.true + assert Or(-y < -x, x >= y).simplify() == S.true + assert Or(x < y, -x <= -y).simplify() == S.true + assert Or(-x > -y, -x <= -y).simplify() == S.true + assert Or(y > x, -x <= -y).simplify() == S.true + assert Or(-y < -x, -x <= -y).simplify() == S.true + assert Or(x < y, y <= x).simplify() == S.true + assert Or(y > x, y <= x).simplify() == S.true + assert Or(-x > -y, y <= x).simplify() == S.true + assert Or(-y < -x, y <= x).simplify() == S.true + assert Or(x < y, -y >= -x).simplify() == S.true + assert Or(y > x, -y >= -x).simplify() == S.true + assert Or(-x > -y, -y >= -x).simplify() == S.true + assert Or(-y < -x, -y >= -x).simplify() == S.true + + # Some other tests + assert Or(x >= y, w < z, x <= y).simplify() == S.true + assert And(x >= y, x < y).simplify() == S.false + assert Or(x >= y, Eq(y, x)).simplify() == (x >= y) + assert And(x >= y, Eq(y, x)).simplify() == Eq(x, y) + assert And(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y).simplify() == \ + (Eq(x, y) & (x >= 1) & (y >= 5) & (y > z)) + assert Or(Eq(x, y), x >= y, w < y, z < y).simplify() == \ + (x >= y) | (y > z) | (w < y) + assert And(Eq(x, y), x >= y, w < y, y >= z, z < y).simplify() == \ + Eq(x, y) & (y > z) & (w < y) + # assert And(Eq(x, y), x >= y, w < y, y >= z, z < y).simplify(relational_minmax=True) == \ + # And(Eq(x, y), y > Max(w, z)) + # assert Or(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y).simplify(relational_minmax=True) == \ + # (Eq(x, y) | (x >= 1) | (y > Min(2, z))) + assert And(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y).simplify() == \ + (Eq(x, y) & (x >= 1) & (y >= 5) & (y > z)) + assert (Eq(x, y) & Eq(d, e) & (x >= y) & (d >= e)).simplify() == \ + (Eq(x, y) & Eq(d, e) & (d >= e)) + assert And(Eq(x, y), Eq(x, -y)).simplify() == And(Eq(x, 0), Eq(y, 0)) + assert Xor(x >= y, x <= y).simplify() == Ne(x, y) + assert And(x > 1, x < -1, Eq(x, y)).simplify() == S.false + # From #16690 + assert And(x >= y, Eq(y, 0)).simplify() == And(x >= 0, Eq(y, 0)) + assert Or(Ne(x, 1), Ne(x, 2)).simplify() == S.true + assert And(Eq(x, 1), Ne(2, x)).simplify() == Eq(x, 1) + assert Or(Eq(x, 1), Ne(2, x)).simplify() == Ne(x, 2) + + +def test_issue_8373(): + x = symbols('x', real=True) + assert Or(x < 1, x > -1).simplify() == S.true + assert Or(x < 1, x >= 1).simplify() == S.true + assert And(x < 1, x >= 1).simplify() == S.false + assert Or(x <= 1, x >= 1).simplify() == S.true + + +def test_issue_7950(): + x = symbols('x', real=True) + assert And(Eq(x, 1), Eq(x, 2)).simplify() == S.false + + +@slow +def test_relational_simplification_numerically(): + def test_simplification_numerically_function(original, simplified): + symb = original.free_symbols + n = len(symb) + valuelist = list(set(combinations(list(range(-(n - 1), n)) * n, n))) + for values in valuelist: + sublist = dict(zip(symb, values)) + originalvalue = original.subs(sublist) + simplifiedvalue = simplified.subs(sublist) + assert originalvalue == simplifiedvalue, "Original: {}\nand" \ + " simplified: {}\ndo not evaluate to the same value for {}" \ + "".format(original, simplified, sublist) + + w, x, y, z = symbols('w x y z', real=True) + d, e = symbols('d e', real=False) + + expressions = (And(Eq(x, y), x >= y, w < y, y >= z, z < y), + And(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y), + Or(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y), + And(x >= y, Eq(y, x)), + Or(And(Eq(x, y), x >= y, w < y, Or(y >= z, z < y)), + And(Eq(x, y), x >= 1, 2 < y, y >= -1, z < y)), + (Eq(x, y) & Eq(d, e) & (x >= y) & (d >= e)), + ) + + for expression in expressions: + test_simplification_numerically_function(expression, + expression.simplify()) + + +def test_relational_simplification_patterns_numerically(): + from sympy.core import Wild + from sympy.logic.boolalg import _simplify_patterns_and, \ + _simplify_patterns_or, _simplify_patterns_xor + a = Wild('a') + b = Wild('b') + c = Wild('c') + symb = [a, b, c] + patternlists = [[And, _simplify_patterns_and()], + [Or, _simplify_patterns_or()], + [Xor, _simplify_patterns_xor()]] + valuelist = list(set(combinations(list(range(-2, 3)) * 3, 3))) + # Skip combinations of +/-2 and 0, except for all 0 + valuelist = [v for v in valuelist if any(w % 2 for w in v) or not any(v)] + for func, patternlist in patternlists: + for pattern in patternlist: + original = func(*pattern[0].args) + simplified = pattern[1] + for values in valuelist: + sublist = dict(zip(symb, values)) + originalvalue = original.xreplace(sublist) + simplifiedvalue = simplified.xreplace(sublist) + assert originalvalue == simplifiedvalue, "Original: {}\nand" \ + " simplified: {}\ndo not evaluate to the same value for" \ + "{}".format(pattern[0], simplified, sublist) + + +def test_issue_16803(): + n = symbols('n') + # No simplification done, but should not raise an exception + assert ((n > 3) | (n < 0) | ((n > 0) & (n < 3))).simplify() == \ + (n > 3) | (n < 0) | ((n > 0) & (n < 3)) + + +def test_issue_17530(): + r = {x: oo, y: oo} + assert Or(x + y > 0, x - y < 0).subs(r) + assert not And(x + y < 0, x - y < 0).subs(r) + raises(TypeError, lambda: Or(x + y < 0, x - y < 0).subs(r)) + raises(TypeError, lambda: And(x + y > 0, x - y < 0).subs(r)) + raises(TypeError, lambda: And(x + y > 0, x - y < 0).subs(r)) + + +def test_anf_coeffs(): + assert anf_coeffs([1, 0]) == [1, 1] + assert anf_coeffs([0, 0, 0, 1]) == [0, 0, 0, 1] + assert anf_coeffs([0, 1, 1, 1]) == [0, 1, 1, 1] + assert anf_coeffs([1, 1, 1, 0]) == [1, 0, 0, 1] + assert anf_coeffs([1, 0, 0, 0]) == [1, 1, 1, 1] + assert anf_coeffs([1, 0, 0, 1]) == [1, 1, 1, 0] + assert anf_coeffs([1, 1, 0, 1]) == [1, 0, 1, 1] + + +def test_ANFform(): + x, y = symbols('x,y') + assert ANFform([x], [1, 1]) == True + assert ANFform([x], [0, 0]) == False + assert ANFform([x], [1, 0]) == Xor(x, True, remove_true=False) + assert ANFform([x, y], [1, 1, 1, 0]) == \ + Xor(True, And(x, y), remove_true=False) + + +def test_bool_minterm(): + x, y = symbols('x,y') + assert bool_minterm(3, [x, y]) == And(x, y) + assert bool_minterm([1, 0], [x, y]) == And(Not(y), x) + + +def test_bool_maxterm(): + x, y = symbols('x,y') + assert bool_maxterm(2, [x, y]) == Or(Not(x), y) + assert bool_maxterm([0, 1], [x, y]) == Or(Not(y), x) + + +def test_bool_monomial(): + x, y = symbols('x,y') + assert bool_monomial(1, [x, y]) == y + assert bool_monomial([1, 1], [x, y]) == And(x, y) + + +def test_check_pair(): + assert _check_pair([0, 1, 0], [0, 1, 1]) == 2 + assert _check_pair([0, 1, 0], [1, 1, 1]) == -1 + + +def test_issue_19114(): + expr = (B & C) | (A & ~C) | (~A & ~B) + # Expression is minimal, but there are multiple minimal forms possible + res1 = (A & B) | (C & ~A) | (~B & ~C) + result = to_dnf(expr, simplify=True) + assert result in (expr, res1) + + +def test_issue_20870(): + result = SOPform([a, b, c, d], [1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 14, 15]) + expected = ((d & ~b) | (a & b & c) | (a & ~c & ~d) | + (b & ~a & ~c) | (c & ~a & ~d)) + assert result == expected + + +def test_convert_to_varsSOP(): + assert _convert_to_varsSOP([0, 1, 0], [x, y, z]) == And(Not(x), y, Not(z)) + assert _convert_to_varsSOP([3, 1, 0], [x, y, z]) == And(y, Not(z)) + + +def test_convert_to_varsPOS(): + assert _convert_to_varsPOS([0, 1, 0], [x, y, z]) == Or(x, Not(y), z) + assert _convert_to_varsPOS([3, 1, 0], [x, y, z]) == Or(Not(y), z) + + +def test_gateinputcount(): + a, b, c, d, e = symbols('a:e') + assert gateinputcount(And(a, b)) == 2 + assert gateinputcount(a | b & c & d ^ (e | a)) == 9 + assert gateinputcount(And(a, True)) == 0 + raises(TypeError, lambda: gateinputcount(a * b)) + + +def test_refine(): + # relational + assert not refine(x < 0, ~(x < 0)) + assert refine(x < 0, (x < 0)) + assert refine(x < 0, (0 > x)) is S.true + assert refine(x < 0, (y < 0)) == (x < 0) + assert not refine(x <= 0, ~(x <= 0)) + assert refine(x <= 0, (x <= 0)) + assert refine(x <= 0, (0 >= x)) is S.true + assert refine(x <= 0, (y <= 0)) == (x <= 0) + assert not refine(x > 0, ~(x > 0)) + assert refine(x > 0, (x > 0)) + assert refine(x > 0, (0 < x)) is S.true + assert refine(x > 0, (y > 0)) == (x > 0) + assert not refine(x >= 0, ~(x >= 0)) + assert refine(x >= 0, (x >= 0)) + assert refine(x >= 0, (0 <= x)) is S.true + assert refine(x >= 0, (y >= 0)) == (x >= 0) + assert not refine(Eq(x, 0), ~(Eq(x, 0))) + assert refine(Eq(x, 0), (Eq(x, 0))) + assert refine(Eq(x, 0), (Eq(0, x))) is S.true + assert refine(Eq(x, 0), (Eq(y, 0))) == Eq(x, 0) + assert not refine(Ne(x, 0), ~(Ne(x, 0))) + assert refine(Ne(x, 0), (Ne(0, x))) is S.true + assert refine(Ne(x, 0), (Ne(x, 0))) + assert refine(Ne(x, 0), (Ne(y, 0))) == (Ne(x, 0)) + + # boolean functions + assert refine(And(x > 0, y > 0), (x > 0)) == (y > 0) + assert refine(And(x > 0, y > 0), (x > 0) & (y > 0)) is S.true + + # predicates + assert refine(Q.positive(x), Q.positive(x)) is S.true + assert refine(Q.positive(x), Q.negative(x)) is S.false + assert refine(Q.positive(x), Q.real(x)) == Q.positive(x) + + +def test_relational_threeterm_simplification_patterns_numerically(): + from sympy.core import Wild + from sympy.logic.boolalg import _simplify_patterns_and3 + a = Wild('a') + b = Wild('b') + c = Wild('c') + symb = [a, b, c] + patternlists = [[And, _simplify_patterns_and3()]] + valuelist = list(set(combinations(list(range(-2, 3)) * 3, 3))) + # Skip combinations of +/-2 and 0, except for all 0 + valuelist = [v for v in valuelist if any(w % 2 for w in v) or not any(v)] + for func, patternlist in patternlists: + for pattern in patternlist: + original = func(*pattern[0].args) + simplified = pattern[1] + for values in valuelist: + sublist = dict(zip(symb, values)) + originalvalue = original.xreplace(sublist) + simplifiedvalue = simplified.xreplace(sublist) + assert originalvalue == simplifiedvalue, "Original: {}\nand" \ + " simplified: {}\ndo not evaluate to the same value for" \ + "{}".format(pattern[0], simplified, sublist) + + +def test_issue_25451(): + x = Or(And(a, c), Eq(a, b)) + assert isinstance(x, Or) + assert set(x.args) == {And(a, c), Eq(a, b)} + + +def test_issue_26985(): + a, b, c, d = symbols('a b c d') + + # Expression before applying to_anf + x = Xor(c, And(a, b), And(a, c)) + y = Xor(a, b, And(a, c)) + + # Applying to_anf + result = Xor(Xor(d, And(x, y)), And(x, y)) + result_anf = to_anf(Xor(to_anf(Xor(d, And(x, y))), And(x, y))) + + assert result_anf == d + assert result == d diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_dimacs.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_dimacs.py new file mode 100644 index 0000000000000000000000000000000000000000..3a9a51a39d33fb807688614cb5809b621ce21a2c --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_dimacs.py @@ -0,0 +1,234 @@ +"""Various tests on satisfiability using dimacs cnf file syntax +You can find lots of cnf files in +ftp://dimacs.rutgers.edu/pub/challenge/satisfiability/benchmarks/cnf/ +""" + +from sympy.logic.utilities.dimacs import load +from sympy.logic.algorithms.dpll import dpll_satisfiable + + +def test_f1(): + assert bool(dpll_satisfiable(load(f1))) + + +def test_f2(): + assert bool(dpll_satisfiable(load(f2))) + + +def test_f3(): + assert bool(dpll_satisfiable(load(f3))) + + +def test_f4(): + assert not bool(dpll_satisfiable(load(f4))) + + +def test_f5(): + assert bool(dpll_satisfiable(load(f5))) + +f1 = """c simple example +c Resolution: SATISFIABLE +c +p cnf 3 2 +1 -3 0 +2 3 -1 0 +""" + + +f2 = """c an example from Quinn's text, 16 variables and 18 clauses. +c Resolution: SATISFIABLE +c +p cnf 16 18 + 1 2 0 + -2 -4 0 + 3 4 0 + -4 -5 0 + 5 -6 0 + 6 -7 0 + 6 7 0 + 7 -16 0 + 8 -9 0 + -8 -14 0 + 9 10 0 + 9 -10 0 +-10 -11 0 + 10 12 0 + 11 12 0 + 13 14 0 + 14 -15 0 + 15 16 0 +""" + +f3 = """c +p cnf 6 9 +-1 0 +-3 0 +2 -1 0 +2 -4 0 +5 -4 0 +-1 -3 0 +-4 -6 0 +1 3 -2 0 +4 6 -2 -5 0 +""" + +f4 = """c +c file: hole6.cnf [http://people.sc.fsu.edu/~jburkardt/data/cnf/hole6.cnf] +c +c SOURCE: John Hooker (jh38+@andrew.cmu.edu) +c +c DESCRIPTION: Pigeon hole problem of placing n (for file 'holen.cnf') pigeons +c in n+1 holes without placing 2 pigeons in the same hole +c +c NOTE: Part of the collection at the Forschungsinstitut fuer +c anwendungsorientierte Wissensverarbeitung in Ulm Germany. +c +c NOTE: Not satisfiable +c +p cnf 42 133 +-1 -7 0 +-1 -13 0 +-1 -19 0 +-1 -25 0 +-1 -31 0 +-1 -37 0 +-7 -13 0 +-7 -19 0 +-7 -25 0 +-7 -31 0 +-7 -37 0 +-13 -19 0 +-13 -25 0 +-13 -31 0 +-13 -37 0 +-19 -25 0 +-19 -31 0 +-19 -37 0 +-25 -31 0 +-25 -37 0 +-31 -37 0 +-2 -8 0 +-2 -14 0 +-2 -20 0 +-2 -26 0 +-2 -32 0 +-2 -38 0 +-8 -14 0 +-8 -20 0 +-8 -26 0 +-8 -32 0 +-8 -38 0 +-14 -20 0 +-14 -26 0 +-14 -32 0 +-14 -38 0 +-20 -26 0 +-20 -32 0 +-20 -38 0 +-26 -32 0 +-26 -38 0 +-32 -38 0 +-3 -9 0 +-3 -15 0 +-3 -21 0 +-3 -27 0 +-3 -33 0 +-3 -39 0 +-9 -15 0 +-9 -21 0 +-9 -27 0 +-9 -33 0 +-9 -39 0 +-15 -21 0 +-15 -27 0 +-15 -33 0 +-15 -39 0 +-21 -27 0 +-21 -33 0 +-21 -39 0 +-27 -33 0 +-27 -39 0 +-33 -39 0 +-4 -10 0 +-4 -16 0 +-4 -22 0 +-4 -28 0 +-4 -34 0 +-4 -40 0 +-10 -16 0 +-10 -22 0 +-10 -28 0 +-10 -34 0 +-10 -40 0 +-16 -22 0 +-16 -28 0 +-16 -34 0 +-16 -40 0 +-22 -28 0 +-22 -34 0 +-22 -40 0 +-28 -34 0 +-28 -40 0 +-34 -40 0 +-5 -11 0 +-5 -17 0 +-5 -23 0 +-5 -29 0 +-5 -35 0 +-5 -41 0 +-11 -17 0 +-11 -23 0 +-11 -29 0 +-11 -35 0 +-11 -41 0 +-17 -23 0 +-17 -29 0 +-17 -35 0 +-17 -41 0 +-23 -29 0 +-23 -35 0 +-23 -41 0 +-29 -35 0 +-29 -41 0 +-35 -41 0 +-6 -12 0 +-6 -18 0 +-6 -24 0 +-6 -30 0 +-6 -36 0 +-6 -42 0 +-12 -18 0 +-12 -24 0 +-12 -30 0 +-12 -36 0 +-12 -42 0 +-18 -24 0 +-18 -30 0 +-18 -36 0 +-18 -42 0 +-24 -30 0 +-24 -36 0 +-24 -42 0 +-30 -36 0 +-30 -42 0 +-36 -42 0 + 6 5 4 3 2 1 0 + 12 11 10 9 8 7 0 + 18 17 16 15 14 13 0 + 24 23 22 21 20 19 0 + 30 29 28 27 26 25 0 + 36 35 34 33 32 31 0 + 42 41 40 39 38 37 0 +""" + +f5 = """c simple example requiring variable selection +c +c NOTE: Satisfiable +c +p cnf 5 5 +1 2 3 0 +1 -2 3 0 +4 5 -3 0 +1 -4 -3 0 +-1 -5 0 +""" diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_inference.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_inference.py new file mode 100644 index 0000000000000000000000000000000000000000..ff37b1b104f6f106ec5df7809fd34959bce35917 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_inference.py @@ -0,0 +1,396 @@ +"""For more tests on satisfiability, see test_dimacs""" + +from sympy.assumptions.ask import Q +from sympy.core.symbol import symbols +from sympy.core.relational import Unequality +from sympy.logic.boolalg import And, Or, Implies, Equivalent, true, false +from sympy.logic.inference import literal_symbol, \ + pl_true, satisfiable, valid, entails, PropKB +from sympy.logic.algorithms.dpll import dpll, dpll_satisfiable, \ + find_pure_symbol, find_unit_clause, unit_propagate, \ + find_pure_symbol_int_repr, find_unit_clause_int_repr, \ + unit_propagate_int_repr +from sympy.logic.algorithms.dpll2 import dpll_satisfiable as dpll2_satisfiable + +from sympy.logic.algorithms.z3_wrapper import z3_satisfiable +from sympy.assumptions.cnf import CNF, EncodedCNF +from sympy.logic.tests.test_lra_theory import make_random_problem +from sympy.core.random import randint + +from sympy.testing.pytest import raises, skip +from sympy.external import import_module + + +def test_literal(): + A, B = symbols('A,B') + assert literal_symbol(True) is True + assert literal_symbol(False) is False + assert literal_symbol(A) is A + assert literal_symbol(~A) is A + + +def test_find_pure_symbol(): + A, B, C = symbols('A,B,C') + assert find_pure_symbol([A], [A]) == (A, True) + assert find_pure_symbol([A, B], [~A | B, ~B | A]) == (None, None) + assert find_pure_symbol([A, B, C], [ A | ~B, ~B | ~C, C | A]) == (A, True) + assert find_pure_symbol([A, B, C], [~A | B, B | ~C, C | A]) == (B, True) + assert find_pure_symbol([A, B, C], [~A | ~B, ~B | ~C, C | A]) == (B, False) + assert find_pure_symbol( + [A, B, C], [~A | B, ~B | ~C, C | A]) == (None, None) + + +def test_find_pure_symbol_int_repr(): + assert find_pure_symbol_int_repr([1], [{1}]) == (1, True) + assert find_pure_symbol_int_repr([1, 2], + [{-1, 2}, {-2, 1}]) == (None, None) + assert find_pure_symbol_int_repr([1, 2, 3], + [{1, -2}, {-2, -3}, {3, 1}]) == (1, True) + assert find_pure_symbol_int_repr([1, 2, 3], + [{-1, 2}, {2, -3}, {3, 1}]) == (2, True) + assert find_pure_symbol_int_repr([1, 2, 3], + [{-1, -2}, {-2, -3}, {3, 1}]) == (2, False) + assert find_pure_symbol_int_repr([1, 2, 3], + [{-1, 2}, {-2, -3}, {3, 1}]) == (None, None) + + +def test_unit_clause(): + A, B, C = symbols('A,B,C') + assert find_unit_clause([A], {}) == (A, True) + assert find_unit_clause([A, ~A], {}) == (A, True) # Wrong ?? + assert find_unit_clause([A | B], {A: True}) == (B, True) + assert find_unit_clause([A | B], {B: True}) == (A, True) + assert find_unit_clause( + [A | B | C, B | ~C, A | ~B], {A: True}) == (B, False) + assert find_unit_clause([A | B | C, B | ~C, A | B], {A: True}) == (B, True) + assert find_unit_clause([A | B | C, B | ~C, A ], {}) == (A, True) + + +def test_unit_clause_int_repr(): + assert find_unit_clause_int_repr(map(set, [[1]]), {}) == (1, True) + assert find_unit_clause_int_repr(map(set, [[1], [-1]]), {}) == (1, True) + assert find_unit_clause_int_repr([{1, 2}], {1: True}) == (2, True) + assert find_unit_clause_int_repr([{1, 2}], {2: True}) == (1, True) + assert find_unit_clause_int_repr(map(set, + [[1, 2, 3], [2, -3], [1, -2]]), {1: True}) == (2, False) + assert find_unit_clause_int_repr(map(set, + [[1, 2, 3], [3, -3], [1, 2]]), {1: True}) == (2, True) + + A, B, C = symbols('A,B,C') + assert find_unit_clause([A | B | C, B | ~C, A ], {}) == (A, True) + + +def test_unit_propagate(): + A, B, C = symbols('A,B,C') + assert unit_propagate([A | B], A) == [] + assert unit_propagate([A | B, ~A | C, ~C | B, A], A) == [C, ~C | B, A] + + +def test_unit_propagate_int_repr(): + assert unit_propagate_int_repr([{1, 2}], 1) == [] + assert unit_propagate_int_repr(map(set, + [[1, 2], [-1, 3], [-3, 2], [1]]), 1) == [{3}, {-3, 2}] + + +def test_dpll(): + """This is also tested in test_dimacs""" + A, B, C = symbols('A,B,C') + assert dpll([A | B], [A, B], {A: True, B: True}) == {A: True, B: True} + + +def test_dpll_satisfiable(): + A, B, C = symbols('A,B,C') + assert dpll_satisfiable( A & ~A ) is False + assert dpll_satisfiable( A & ~B ) == {A: True, B: False} + assert dpll_satisfiable( + A | B ) in ({A: True}, {B: True}, {A: True, B: True}) + assert dpll_satisfiable( + (~A | B) & (~B | A) ) in ({A: True, B: True}, {A: False, B: False}) + assert dpll_satisfiable( (A | B) & (~B | C) ) in ({A: True, B: False}, + {A: True, C: True}, {B: True, C: True}) + assert dpll_satisfiable( A & B & C ) == {A: True, B: True, C: True} + assert dpll_satisfiable( (A | B) & (A >> B) ) == {B: True} + assert dpll_satisfiable( Equivalent(A, B) & A ) == {A: True, B: True} + assert dpll_satisfiable( Equivalent(A, B) & ~A ) == {A: False, B: False} + + +def test_dpll2_satisfiable(): + A, B, C = symbols('A,B,C') + assert dpll2_satisfiable( A & ~A ) is False + assert dpll2_satisfiable( A & ~B ) == {A: True, B: False} + assert dpll2_satisfiable( + A | B ) in ({A: True}, {B: True}, {A: True, B: True}) + assert dpll2_satisfiable( + (~A | B) & (~B | A) ) in ({A: True, B: True}, {A: False, B: False}) + assert dpll2_satisfiable( (A | B) & (~B | C) ) in ({A: True, B: False, C: True}, + {A: True, B: True, C: True}) + assert dpll2_satisfiable( A & B & C ) == {A: True, B: True, C: True} + assert dpll2_satisfiable( (A | B) & (A >> B) ) in ({B: True, A: False}, + {B: True, A: True}) + assert dpll2_satisfiable( Equivalent(A, B) & A ) == {A: True, B: True} + assert dpll2_satisfiable( Equivalent(A, B) & ~A ) == {A: False, B: False} + + +def test_minisat22_satisfiable(): + A, B, C = symbols('A,B,C') + minisat22_satisfiable = lambda expr: satisfiable(expr, algorithm="minisat22") + assert minisat22_satisfiable( A & ~A ) is False + assert minisat22_satisfiable( A & ~B ) == {A: True, B: False} + assert minisat22_satisfiable( + A | B ) in ({A: True}, {B: False}, {A: False, B: True}, {A: True, B: True}, {A: True, B: False}) + assert minisat22_satisfiable( + (~A | B) & (~B | A) ) in ({A: True, B: True}, {A: False, B: False}) + assert minisat22_satisfiable( (A | B) & (~B | C) ) in ({A: True, B: False, C: True}, + {A: True, B: True, C: True}, {A: False, B: True, C: True}, {A: True, B: False, C: False}) + assert minisat22_satisfiable( A & B & C ) == {A: True, B: True, C: True} + assert minisat22_satisfiable( (A | B) & (A >> B) ) in ({B: True, A: False}, + {B: True, A: True}) + assert minisat22_satisfiable( Equivalent(A, B) & A ) == {A: True, B: True} + assert minisat22_satisfiable( Equivalent(A, B) & ~A ) == {A: False, B: False} + +def test_minisat22_minimal_satisfiable(): + A, B, C = symbols('A,B,C') + minisat22_satisfiable = lambda expr, minimal=True: satisfiable(expr, algorithm="minisat22", minimal=True) + assert minisat22_satisfiable( A & ~A ) is False + assert minisat22_satisfiable( A & ~B ) == {A: True, B: False} + assert minisat22_satisfiable( + A | B ) in ({A: True}, {B: False}, {A: False, B: True}, {A: True, B: True}, {A: True, B: False}) + assert minisat22_satisfiable( + (~A | B) & (~B | A) ) in ({A: True, B: True}, {A: False, B: False}) + assert minisat22_satisfiable( (A | B) & (~B | C) ) in ({A: True, B: False, C: True}, + {A: True, B: True, C: True}, {A: False, B: True, C: True}, {A: True, B: False, C: False}) + assert minisat22_satisfiable( A & B & C ) == {A: True, B: True, C: True} + assert minisat22_satisfiable( (A | B) & (A >> B) ) in ({B: True, A: False}, + {B: True, A: True}) + assert minisat22_satisfiable( Equivalent(A, B) & A ) == {A: True, B: True} + assert minisat22_satisfiable( Equivalent(A, B) & ~A ) == {A: False, B: False} + g = satisfiable((A | B | C),algorithm="minisat22",minimal=True,all_models=True) + sol = next(g) + first_solution = {key for key, value in sol.items() if value} + sol=next(g) + second_solution = {key for key, value in sol.items() if value} + sol=next(g) + third_solution = {key for key, value in sol.items() if value} + assert not first_solution <= second_solution + assert not second_solution <= third_solution + assert not first_solution <= third_solution + +def test_satisfiable(): + A, B, C = symbols('A,B,C') + assert satisfiable(A & (A >> B) & ~B) is False + + +def test_valid(): + A, B, C = symbols('A,B,C') + assert valid(A >> (B >> A)) is True + assert valid((A >> (B >> C)) >> ((A >> B) >> (A >> C))) is True + assert valid((~B >> ~A) >> (A >> B)) is True + assert valid(A | B | C) is False + assert valid(A >> B) is False + + +def test_pl_true(): + A, B, C = symbols('A,B,C') + assert pl_true(True) is True + assert pl_true( A & B, {A: True, B: True}) is True + assert pl_true( A | B, {A: True}) is True + assert pl_true( A | B, {B: True}) is True + assert pl_true( A | B, {A: None, B: True}) is True + assert pl_true( A >> B, {A: False}) is True + assert pl_true( A | B | ~C, {A: False, B: True, C: True}) is True + assert pl_true(Equivalent(A, B), {A: False, B: False}) is True + + # test for false + assert pl_true(False) is False + assert pl_true( A & B, {A: False, B: False}) is False + assert pl_true( A & B, {A: False}) is False + assert pl_true( A & B, {B: False}) is False + assert pl_true( A | B, {A: False, B: False}) is False + + #test for None + assert pl_true(B, {B: None}) is None + assert pl_true( A & B, {A: True, B: None}) is None + assert pl_true( A >> B, {A: True, B: None}) is None + assert pl_true(Equivalent(A, B), {A: None}) is None + assert pl_true(Equivalent(A, B), {A: True, B: None}) is None + + # Test for deep + assert pl_true(A | B, {A: False}, deep=True) is None + assert pl_true(~A & ~B, {A: False}, deep=True) is None + assert pl_true(A | B, {A: False, B: False}, deep=True) is False + assert pl_true(A & B & (~A | ~B), {A: True}, deep=True) is False + assert pl_true((C >> A) >> (B >> A), {C: True}, deep=True) is True + + +def test_pl_true_wrong_input(): + from sympy.core.numbers import pi + raises(ValueError, lambda: pl_true('John Cleese')) + raises(ValueError, lambda: pl_true(42 + pi + pi ** 2)) + raises(ValueError, lambda: pl_true(42)) + + +def test_entails(): + A, B, C = symbols('A, B, C') + assert entails(A, [A >> B, ~B]) is False + assert entails(B, [Equivalent(A, B), A]) is True + assert entails((A >> B) >> (~A >> ~B)) is False + assert entails((A >> B) >> (~B >> ~A)) is True + + +def test_PropKB(): + A, B, C = symbols('A,B,C') + kb = PropKB() + assert kb.ask(A >> B) is False + assert kb.ask(A >> (B >> A)) is True + kb.tell(A >> B) + kb.tell(B >> C) + assert kb.ask(A) is False + assert kb.ask(B) is False + assert kb.ask(C) is False + assert kb.ask(~A) is False + assert kb.ask(~B) is False + assert kb.ask(~C) is False + assert kb.ask(A >> C) is True + kb.tell(A) + assert kb.ask(A) is True + assert kb.ask(B) is True + assert kb.ask(C) is True + assert kb.ask(~C) is False + kb.retract(A) + assert kb.ask(C) is False + + +def test_propKB_tolerant(): + """"tolerant to bad input""" + kb = PropKB() + A, B, C = symbols('A,B,C') + assert kb.ask(B) is False + +def test_satisfiable_non_symbols(): + x, y = symbols('x y') + assumptions = Q.zero(x*y) + facts = Implies(Q.zero(x*y), Q.zero(x) | Q.zero(y)) + query = ~Q.zero(x) & ~Q.zero(y) + refutations = [ + {Q.zero(x): True, Q.zero(x*y): True}, + {Q.zero(y): True, Q.zero(x*y): True}, + {Q.zero(x): True, Q.zero(y): True, Q.zero(x*y): True}, + {Q.zero(x): True, Q.zero(y): False, Q.zero(x*y): True}, + {Q.zero(x): False, Q.zero(y): True, Q.zero(x*y): True}] + assert not satisfiable(And(assumptions, facts, query), algorithm='dpll') + assert satisfiable(And(assumptions, facts, ~query), algorithm='dpll') in refutations + assert not satisfiable(And(assumptions, facts, query), algorithm='dpll2') + assert satisfiable(And(assumptions, facts, ~query), algorithm='dpll2') in refutations + +def test_satisfiable_bool(): + from sympy.core.singleton import S + assert satisfiable(true) == {true: true} + assert satisfiable(S.true) == {true: true} + assert satisfiable(false) is False + assert satisfiable(S.false) is False + + +def test_satisfiable_all_models(): + from sympy.abc import A, B + assert next(satisfiable(False, all_models=True)) is False + assert list(satisfiable((A >> ~A) & A, all_models=True)) == [False] + assert list(satisfiable(True, all_models=True)) == [{true: true}] + + models = [{A: True, B: False}, {A: False, B: True}] + result = satisfiable(A ^ B, all_models=True) + models.remove(next(result)) + models.remove(next(result)) + raises(StopIteration, lambda: next(result)) + assert not models + + assert list(satisfiable(Equivalent(A, B), all_models=True)) == \ + [{A: False, B: False}, {A: True, B: True}] + + models = [{A: False, B: False}, {A: False, B: True}, {A: True, B: True}] + for model in satisfiable(A >> B, all_models=True): + models.remove(model) + assert not models + + # This is a santiy test to check that only the required number + # of solutions are generated. The expr below has 2**100 - 1 models + # which would time out the test if all are generated at once. + from sympy.utilities.iterables import numbered_symbols + from sympy.logic.boolalg import Or + sym = numbered_symbols() + X = [next(sym) for i in range(100)] + result = satisfiable(Or(*X), all_models=True) + for i in range(10): + assert next(result) + + +def test_z3(): + z3 = import_module("z3") + + if not z3: + skip("z3 not installed.") + A, B, C = symbols('A,B,C') + x, y, z = symbols('x,y,z') + assert z3_satisfiable((x >= 2) & (x < 1)) is False + assert z3_satisfiable( A & ~A ) is False + + model = z3_satisfiable(A & (~A | B | C)) + assert bool(model) is True + assert model[A] is True + + # test nonlinear function + assert z3_satisfiable((x ** 2 >= 2) & (x < 1) & (x > -1)) is False + + +def test_z3_vs_lra_dpll2(): + z3 = import_module("z3") + if z3 is None: + skip("z3 not installed.") + + def boolean_formula_to_encoded_cnf(bf): + cnf = CNF.from_prop(bf) + enc = EncodedCNF() + enc.from_cnf(cnf) + return enc + + def make_random_cnf(num_clauses=5, num_constraints=10, num_var=2): + assert num_clauses <= num_constraints + constraints = make_random_problem(num_variables=num_var, num_constraints=num_constraints, rational=False) + clauses = [[cons] for cons in constraints[:num_clauses]] + for cons in constraints[num_clauses:]: + if isinstance(cons, Unequality): + cons = ~cons + i = randint(0, num_clauses-1) + clauses[i].append(cons) + + clauses = [Or(*clause) for clause in clauses] + cnf = And(*clauses) + return boolean_formula_to_encoded_cnf(cnf) + + lra_dpll2_satisfiable = lambda x: dpll2_satisfiable(x, use_lra_theory=True) + + for _ in range(50): + cnf = make_random_cnf(num_clauses=10, num_constraints=15, num_var=2) + + try: + z3_sat = z3_satisfiable(cnf) + except z3.z3types.Z3Exception: + continue + + lra_dpll2_sat = lra_dpll2_satisfiable(cnf) is not False + + assert z3_sat == lra_dpll2_sat + +def test_issue_27733(): + x, y = symbols('x,y') + clauses = [[1, -3, -2], [5, 7, -8, -6, -4], [-10, -9, 10, 11, -4], [-12, 13, 14], [-10, 9, -6, 11, -4], + [16, -15, 18, -19, -17], [11, -6, 10, -9], [9, 11, -10, -9], [2, -3, -1], [-13, 12], [-15, 3, -17], + [-16, -15, 19, -17], [-6, -9, 10, 11, -4], [20, -1, -2], [-23, -22, -21], [10, 11, -10, -9], + [9, 11, -4, -10], [24, -6, -4], [-14, 12], [-10, -9, 9, -6, 11], [25, -27, -26], [-15, 19, -18, -17], + [5, 8, -7, -6, -4], [-30, -29, 28], [12], [14]] + + encoding = {Q.gt(y, i): i for i in range(1, 31) if i != 11 and i != 12} + encoding[Q.gt(x, 0)] = 11 + encoding[Q.lt(x, 0)] = 12 + + cnf = EncodedCNF(clauses, encoding) + assert satisfiable(cnf, use_lra_theory=True) is False diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_lra_theory.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_lra_theory.py new file mode 100644 index 0000000000000000000000000000000000000000..207a3c5ba2c1b16ee5323382deee0863a5dfb595 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/tests/test_lra_theory.py @@ -0,0 +1,440 @@ +from sympy.core.numbers import Rational, I, oo +from sympy.core.relational import Eq +from sympy.core.symbol import symbols +from sympy.core.singleton import S +from sympy.matrices.dense import Matrix +from sympy.matrices.dense import randMatrix +from sympy.assumptions.ask import Q +from sympy.logic.boolalg import And +from sympy.abc import x, y, z +from sympy.assumptions.cnf import CNF, EncodedCNF +from sympy.functions.elementary.trigonometric import cos +from sympy.external import import_module + +from sympy.logic.algorithms.lra_theory import LRASolver, UnhandledInput, LRARational, HANDLE_NEGATION +from sympy.core.random import random, choice, randint +from sympy.core.sympify import sympify +from sympy.ntheory.generate import randprime +from sympy.core.relational import StrictLessThan, StrictGreaterThan +import itertools + +from sympy.testing.pytest import raises, XFAIL, skip + +def make_random_problem(num_variables=2, num_constraints=2, sparsity=.1, rational=True, + disable_strict = False, disable_nonstrict=False, disable_equality=False): + def rand(sparsity=sparsity): + if random() < sparsity: + return sympify(0) + if rational: + int1, int2 = [randprime(0, 50) for _ in range(2)] + return Rational(int1, int2) * choice([-1, 1]) + else: + return randint(1, 10) * choice([-1, 1]) + + variables = symbols('x1:%s' % (num_variables + 1)) + constraints = [] + for _ in range(num_constraints): + lhs, rhs = sum(rand() * x for x in variables), rand(sparsity=0) # sparsity=0 bc of bug with smtlib_code + options = [] + if not disable_equality: + options += [Eq(lhs, rhs)] + if not disable_nonstrict: + options += [lhs <= rhs, lhs >= rhs] + if not disable_strict: + options += [lhs < rhs, lhs > rhs] + + constraints.append(choice(options)) + + return constraints + +def check_if_satisfiable_with_z3(constraints): + from sympy.external.importtools import import_module + from sympy.printing.smtlib import smtlib_code + from sympy.logic.boolalg import And + boolean_formula = And(*constraints) + z3 = import_module("z3") + if z3: + smtlib_string = smtlib_code(boolean_formula) + s = z3.Solver() + s.from_string(smtlib_string) + res = str(s.check()) + if res == 'sat': + return True + elif res == 'unsat': + return False + else: + raise ValueError(f"z3 was not able to check the satisfiability of {boolean_formula}") + +def find_rational_assignment(constr, assignment, iter=20): + eps = sympify(1) + + for _ in range(iter): + assign = {key: val[0] + val[1]*eps for key, val in assignment.items()} + try: + for cons in constr: + assert cons.subs(assign) == True + return assign + except AssertionError: + eps = eps/2 + + return None + +def boolean_formula_to_encoded_cnf(bf): + cnf = CNF.from_prop(bf) + enc = EncodedCNF() + enc.from_cnf(cnf) + return enc + + +def test_from_encoded_cnf(): + s1, s2 = symbols("s1 s2") + + # Test preprocessing + # Example is from section 3 of paper. + phi = (x >= 0) & ((x + y <= 2) | (x + 2 * y - z >= 6)) & (Eq(x + y, 2) | (x + 2 * y - z > 4)) + enc = boolean_formula_to_encoded_cnf(phi) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + assert lra.A.shape == (2, 5) + assert str(lra.slack) == '[_s1, _s2]' + assert str(lra.nonslack) == '[x, y, z]' + assert lra.A == Matrix([[ 1, 1, 0, -1, 0], + [-1, -2, 1, 0, -1]]) + assert {(str(b.var), b.bound, b.upper, b.equality, b.strict) for b in lra.enc_to_boundary.values()} == {('_s1', 2, None, True, False), + ('_s1', 2, True, False, False), + ('_s2', -4, True, False, True), + ('_s2', -6, True, False, False), + ('x', 0, False, False, False)} + + +def test_problem(): + from sympy.logic.algorithms.lra_theory import LRASolver + from sympy.assumptions.cnf import CNF, EncodedCNF + cons = [-2 * x - 2 * y >= 7, -9 * y >= 7, -6 * y >= 5] + cnf = CNF().from_prop(And(*cons)) + enc = EncodedCNF() + enc.from_cnf(cnf) + lra, _ = LRASolver.from_encoded_cnf(enc) + lra.assert_lit(1) + lra.assert_lit(2) + lra.assert_lit(3) + is_sat, assignment = lra.check() + assert is_sat is True + + +def test_random_problems(): + z3 = import_module("z3") + if z3 is None: + skip("z3 is not installed") + + special_cases = []; x1, x2, x3 = symbols("x1 x2 x3") + special_cases.append([x1 - 3 * x2 <= -5, 6 * x1 + 4 * x2 <= 0, -7 * x1 + 3 * x2 <= 3]) + special_cases.append([-3 * x1 >= 3, Eq(4 * x1, -1)]) + special_cases.append([-4 * x1 < 4, 6 * x1 <= -6]) + special_cases.append([-3 * x2 >= 7, 6 * x1 <= -5, -3 * x2 <= -4]) + special_cases.append([x + y >= 2, x + y <= 1]) + special_cases.append([x >= 0, x + y <= 2, x + 2 * y - z >= 6]) # from paper example + special_cases.append([-2 * x1 - 2 * x2 >= 7, -9 * x1 >= 7, -6 * x1 >= 5]) + special_cases.append([2 * x1 > -3, -9 * x1 < -6, 9 * x1 <= 6]) + special_cases.append([-2*x1 < -4, 9*x1 > -9]) + special_cases.append([-6*x1 >= -1, -8*x1 + x2 >= 5, -8*x1 + 7*x2 < 4, x1 > 7]) + special_cases.append([Eq(x1, 2), Eq(5*x1, -2), Eq(-7*x2, -6), Eq(9*x1 + 10*x2, 9)]) + special_cases.append([Eq(3*x1, 6), Eq(x1 - 8*x2, -9), Eq(-7*x1 + 5*x2, 3), Eq(3*x2, 7)]) + special_cases.append([-4*x1 < 4, 6*x1 <= -6]) + special_cases.append([-3*x1 + 8*x2 >= -8, -10*x2 > 9, 8*x1 - 4*x2 < 8, 10*x1 - 9*x2 >= -9]) + special_cases.append([x1 + 5*x2 >= -6, 9*x1 - 3*x2 >= -9, 6*x1 + 6*x2 < -10, -3*x1 + 3*x2 < -7]) + special_cases.append([-9*x1 < 7, -5*x1 - 7*x2 < -1, 3*x1 + 7*x2 > 1, -6*x1 - 6*x2 > 9]) + special_cases.append([9*x1 - 6*x2 >= -7, 9*x1 + 4*x2 < -8, -7*x2 <= 1, 10*x2 <= -7]) + + feasible_count = 0 + for i in range(50): + if i % 8 == 0: + constraints = make_random_problem(num_variables=1, num_constraints=2, rational=False) + elif i % 8 == 1: + constraints = make_random_problem(num_variables=2, num_constraints=4, rational=False, disable_equality=True, + disable_nonstrict=True) + elif i % 8 == 2: + constraints = make_random_problem(num_variables=2, num_constraints=4, rational=False, disable_strict=True) + elif i % 8 == 3: + constraints = make_random_problem(num_variables=3, num_constraints=12, rational=False) + else: + constraints = make_random_problem(num_variables=3, num_constraints=6, rational=False) + + if i < len(special_cases): + constraints = special_cases[i] + + if False in constraints or True in constraints: + continue + + phi = And(*constraints) + if phi == False: + continue + cnf = CNF.from_prop(phi); enc = EncodedCNF() + enc.from_cnf(cnf) + assert all(0 not in clause for clause in enc.data) + + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + s_subs = lra.s_subs + + lra.run_checks = True + s_subs_rev = {value: key for key, value in s_subs.items()} + lits = {lit for clause in enc.data for lit in clause} + + bounds = [(lra.enc_to_boundary[l], l) for l in lits if l in lra.enc_to_boundary] + bounds = sorted(bounds, key=lambda x: (str(x[0].var), x[0].bound, str(x[0].upper))) # to remove nondeterminism + + for b, l in bounds: + if lra.result and lra.result[0] == False: + break + lra.assert_lit(l) + + feasible = lra.check() + + if feasible[0] == True: + feasible_count += 1 + assert check_if_satisfiable_with_z3(constraints) is True + cons_funcs = [cons.func for cons in constraints] + assignment = feasible[1] + assignment = {key.var : value for key, value in assignment.items()} + if not (StrictLessThan in cons_funcs or StrictGreaterThan in cons_funcs): + assignment = {key: value[0] for key, value in assignment.items()} + for cons in constraints: + assert cons.subs(assignment) == True + + else: + rat_assignment = find_rational_assignment(constraints, assignment) + assert rat_assignment is not None + else: + assert check_if_satisfiable_with_z3(constraints) is False + + conflict = feasible[1] + assert len(conflict) >= 2 + conflict = {lra.enc_to_boundary[-l].get_inequality() for l in conflict} + conflict = {clause.subs(s_subs_rev) for clause in conflict} + assert check_if_satisfiable_with_z3(conflict) is False + + # check that conflict clause is probably minimal + for subset in itertools.combinations(conflict, len(conflict)-1): + assert check_if_satisfiable_with_z3(subset) is True + + +@XFAIL +def test_pos_neg_zero(): + bf = Q.positive(x) & Q.negative(x) & Q.zero(y) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for lit in enc.encoding.values(): + if lra.assert_lit(lit) is not None: + break + assert len(lra.enc_to_boundary) == 3 + assert lra.check()[0] == False + + bf = Q.positive(x) & Q.lt(x, -1) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for lit in enc.encoding.values(): + if lra.assert_lit(lit) is not None: + break + assert len(lra.enc_to_boundary) == 2 + assert lra.check()[0] == False + + bf = Q.positive(x) & Q.zero(x) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for lit in enc.encoding.values(): + if lra.assert_lit(lit) is not None: + break + assert len(lra.enc_to_boundary) == 2 + assert lra.check()[0] == False + + bf = Q.positive(x) & Q.zero(y) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for lit in enc.encoding.values(): + if lra.assert_lit(lit) is not None: + break + assert len(lra.enc_to_boundary) == 2 + assert lra.check()[0] == True + + +@XFAIL +def test_pos_neg_infinite(): + bf = Q.positive_infinite(x) & Q.lt(x, 10000000) & Q.positive_infinite(y) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for lit in enc.encoding.values(): + if lra.assert_lit(lit) is not None: + break + assert len(lra.enc_to_boundary) == 3 + assert lra.check()[0] == False + + bf = Q.positive_infinite(x) & Q.gt(x, 10000000) & Q.positive_infinite(y) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for lit in enc.encoding.values(): + if lra.assert_lit(lit) is not None: + break + assert len(lra.enc_to_boundary) == 3 + assert lra.check()[0] == True + + bf = Q.positive_infinite(x) & Q.negative_infinite(x) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for lit in enc.encoding.values(): + if lra.assert_lit(lit) is not None: + break + assert len(lra.enc_to_boundary) == 2 + assert lra.check()[0] == False + + +def test_binrel_evaluation(): + bf = Q.gt(3, 2) + enc = boolean_formula_to_encoded_cnf(bf) + lra, conflicts = LRASolver.from_encoded_cnf(enc, testing_mode=True) + assert len(lra.enc_to_boundary) == 0 + assert conflicts == [[1]] + + bf = Q.lt(3, 2) + enc = boolean_formula_to_encoded_cnf(bf) + lra, conflicts = LRASolver.from_encoded_cnf(enc, testing_mode=True) + assert len(lra.enc_to_boundary) == 0 + assert conflicts == [[-1]] + + +def test_negation(): + assert HANDLE_NEGATION is True + bf = Q.gt(x, 1) & ~Q.gt(x, 0) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for clause in enc.data: + for lit in clause: + lra.assert_lit(lit) + assert len(lra.enc_to_boundary) == 2 + assert lra.check()[0] == False + assert sorted(lra.check()[1]) in [[-1, 2], [-2, 1]] + + bf = ~Q.gt(x, 1) & ~Q.lt(x, 0) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for clause in enc.data: + for lit in clause: + lra.assert_lit(lit) + assert len(lra.enc_to_boundary) == 2 + assert lra.check()[0] == True + + bf = ~Q.gt(x, 0) & ~Q.lt(x, 1) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for clause in enc.data: + for lit in clause: + lra.assert_lit(lit) + assert len(lra.enc_to_boundary) == 2 + assert lra.check()[0] == False + + bf = ~Q.gt(x, 0) & ~Q.le(x, 0) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for clause in enc.data: + for lit in clause: + lra.assert_lit(lit) + assert len(lra.enc_to_boundary) == 2 + assert lra.check()[0] == False + + bf = ~Q.le(x+y, 2) & ~Q.ge(x-y, 2) & ~Q.ge(y, 0) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for clause in enc.data: + for lit in clause: + lra.assert_lit(lit) + assert len(lra.enc_to_boundary) == 3 + assert lra.check()[0] == False + assert len(lra.check()[1]) == 3 + assert all(i > 0 for i in lra.check()[1]) + + +def test_unhandled_input(): + nan = S.NaN + bf = Q.gt(3, nan) & Q.gt(x, nan) + enc = boolean_formula_to_encoded_cnf(bf) + raises(ValueError, lambda: LRASolver.from_encoded_cnf(enc, testing_mode=True)) + + bf = Q.gt(3, I) & Q.gt(x, I) + enc = boolean_formula_to_encoded_cnf(bf) + raises(UnhandledInput, lambda: LRASolver.from_encoded_cnf(enc, testing_mode=True)) + + bf = Q.gt(3, float("inf")) & Q.gt(x, float("inf")) + enc = boolean_formula_to_encoded_cnf(bf) + raises(UnhandledInput, lambda: LRASolver.from_encoded_cnf(enc, testing_mode=True)) + + bf = Q.gt(3, oo) & Q.gt(x, oo) + enc = boolean_formula_to_encoded_cnf(bf) + raises(UnhandledInput, lambda: LRASolver.from_encoded_cnf(enc, testing_mode=True)) + + # test non-linearity + bf = Q.gt(x**2 + x, 2) + enc = boolean_formula_to_encoded_cnf(bf) + raises(UnhandledInput, lambda: LRASolver.from_encoded_cnf(enc, testing_mode=True)) + + bf = Q.gt(cos(x) + x, 2) + enc = boolean_formula_to_encoded_cnf(bf) + raises(UnhandledInput, lambda: LRASolver.from_encoded_cnf(enc, testing_mode=True)) + +@XFAIL +def test_infinite_strict_inequalities(): + # Extensive testing of the interaction between strict inequalities + # and constraints containing infinity is needed because + # the paper's rule for strict inequalities don't work when + # infinite numbers are allowed. Using the paper's rules you + # can end up with situations where oo + delta > oo is considered + # True when oo + delta should be equal to oo. + # See https://math.stackexchange.com/questions/4757069/can-this-method-of-converting-strict-inequalities-to-equisatisfiable-nonstrict-i + bf = (-x - y >= -float("inf")) & (x > 0) & (y >= float("inf")) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for lit in sorted(enc.encoding.values()): + if lra.assert_lit(lit) is not None: + break + assert len(lra.enc_to_boundary) == 3 + assert lra.check()[0] == True + + +def test_pivot(): + for _ in range(10): + m = randMatrix(5) + rref = m.rref() + for _ in range(5): + i, j = randint(0, 4), randint(0, 4) + if m[i, j] != 0: + assert LRASolver._pivot(m, i, j).rref() == rref + + +def test_reset_bounds(): + bf = Q.ge(x, 1) & Q.lt(x, 1) + enc = boolean_formula_to_encoded_cnf(bf) + lra, _ = LRASolver.from_encoded_cnf(enc, testing_mode=True) + for clause in enc.data: + for lit in clause: + lra.assert_lit(lit) + assert len(lra.enc_to_boundary) == 2 + assert lra.check()[0] == False + + lra.reset_bounds() + assert lra.check()[0] == True + for var in lra.all_var: + assert var.upper == LRARational(float("inf"), 0) + assert var.upper_from_eq == False + assert var.upper_from_neg == False + assert var.lower == LRARational(-float("inf"), 0) + assert var.lower_from_eq == False + assert var.lower_from_neg == False + assert var.assign == LRARational(0, 0) + assert var.var is not None + assert var.col_idx is not None + + +def test_empty_cnf(): + cnf = CNF() + enc = EncodedCNF() + enc.from_cnf(cnf) + lra, conflict = LRASolver.from_encoded_cnf(enc) + assert len(conflict) == 0 + assert lra.check() == (True, {}) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/utilities/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/utilities/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..3526c3e53d624bc70afe2df05f123c835781364c --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/utilities/__init__.py @@ -0,0 +1,3 @@ +from .dimacs import load_file + +__all__ = ['load_file'] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/utilities/dimacs.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/utilities/dimacs.py new file mode 100644 index 0000000000000000000000000000000000000000..51302d8052c8ed8443239c1e21a2f063cf34e4ab --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/logic/utilities/dimacs.py @@ -0,0 +1,69 @@ +"""For reading in DIMACS file format + +www.cs.ubc.ca/~hoos/SATLIB/Benchmarks/SAT/satformat.ps + +""" + +from sympy.core import Symbol +from sympy.logic.boolalg import And, Or +import re +from pathlib import Path + + +def load(s): + """Loads a boolean expression from a string. + + Examples + ======== + + >>> from sympy.logic.utilities.dimacs import load + >>> load('1') + cnf_1 + >>> load('1 2') + cnf_1 | cnf_2 + >>> load('1 \\n 2') + cnf_1 & cnf_2 + >>> load('1 2 \\n 3') + cnf_3 & (cnf_1 | cnf_2) + """ + clauses = [] + + lines = s.split('\n') + + pComment = re.compile(r'c.*') + pStats = re.compile(r'p\s*cnf\s*(\d*)\s*(\d*)') + + while len(lines) > 0: + line = lines.pop(0) + + # Only deal with lines that aren't comments + if not pComment.match(line): + m = pStats.match(line) + + if not m: + nums = line.rstrip('\n').split(' ') + list = [] + for lit in nums: + if lit != '': + if int(lit) == 0: + continue + num = abs(int(lit)) + sign = True + if int(lit) < 0: + sign = False + + if sign: + list.append(Symbol("cnf_%s" % num)) + else: + list.append(~Symbol("cnf_%s" % num)) + + if len(list) > 0: + clauses.append(Or(*list)) + + return And(*clauses) + + +def load_file(location): + """Loads a boolean expression from a file.""" + s = Path(location).read_text() + return load(s) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/__init__.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/__init__.py new file mode 100644 index 0000000000000000000000000000000000000000..37b558f3f03f149dae6af20254e9b88192f7f1ed --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/__init__.py @@ -0,0 +1,72 @@ +"""A module that handles matrices. + +Includes functions for fast creating matrices like zero, one/eye, random +matrix, etc. +""" +from .exceptions import ShapeError, NonSquareMatrixError +from .kind import MatrixKind +from .dense import ( + GramSchmidt, casoratian, diag, eye, hessian, jordan_cell, + list2numpy, matrix2numpy, matrix_multiply_elementwise, ones, + randMatrix, rot_axis1, rot_axis2, rot_axis3, rot_ccw_axis1, + rot_ccw_axis2, rot_ccw_axis3, rot_givens, + symarray, wronskian, zeros) +from .dense import MutableDenseMatrix +from .matrixbase import DeferredVector, MatrixBase + +MutableMatrix = MutableDenseMatrix +Matrix = MutableMatrix + +from .sparse import MutableSparseMatrix +from .sparsetools import banded +from .immutable import ImmutableDenseMatrix, ImmutableSparseMatrix + +ImmutableMatrix = ImmutableDenseMatrix +SparseMatrix = MutableSparseMatrix + +from .expressions import ( + MatrixSlice, BlockDiagMatrix, BlockMatrix, FunctionMatrix, Identity, + Inverse, MatAdd, MatMul, MatPow, MatrixExpr, MatrixSymbol, Trace, + Transpose, ZeroMatrix, OneMatrix, blockcut, block_collapse, matrix_symbols, Adjoint, + hadamard_product, HadamardProduct, HadamardPower, Determinant, det, + diagonalize_vector, DiagMatrix, DiagonalMatrix, DiagonalOf, trace, + DotProduct, kronecker_product, KroneckerProduct, + PermutationMatrix, MatrixPermute, MatrixSet, Permanent, per) + +from .utilities import dotprodsimp + +__all__ = [ + 'ShapeError', 'NonSquareMatrixError', 'MatrixKind', + + 'GramSchmidt', 'casoratian', 'diag', 'eye', 'hessian', 'jordan_cell', + 'list2numpy', 'matrix2numpy', 'matrix_multiply_elementwise', 'ones', + 'randMatrix', 'rot_axis1', 'rot_axis2', 'rot_axis3', 'symarray', + 'wronskian', 'zeros', 'rot_ccw_axis1', 'rot_ccw_axis2', 'rot_ccw_axis3', + 'rot_givens', + + 'MutableDenseMatrix', + + 'DeferredVector', 'MatrixBase', + + 'Matrix', 'MutableMatrix', + + 'MutableSparseMatrix', + + 'banded', + + 'ImmutableDenseMatrix', 'ImmutableSparseMatrix', + + 'ImmutableMatrix', 'SparseMatrix', + + 'MatrixSlice', 'BlockDiagMatrix', 'BlockMatrix', 'FunctionMatrix', + 'Identity', 'Inverse', 'MatAdd', 'MatMul', 'MatPow', 'MatrixExpr', + 'MatrixSymbol', 'Trace', 'Transpose', 'ZeroMatrix', 'OneMatrix', + 'blockcut', 'block_collapse', 'matrix_symbols', 'Adjoint', + 'hadamard_product', 'HadamardProduct', 'HadamardPower', 'Determinant', + 'det', 'diagonalize_vector', 'DiagMatrix', 'DiagonalMatrix', + 'DiagonalOf', 'trace', 'DotProduct', 'kronecker_product', + 'KroneckerProduct', 'PermutationMatrix', 'MatrixPermute', 'MatrixSet', + 'Permanent', 'per', + + 'dotprodsimp', +] diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/common.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/common.py new file mode 100644 index 0000000000000000000000000000000000000000..bcb54726fe1a0c36658d8bf63b974db5a3ce8bad --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/common.py @@ -0,0 +1,3258 @@ +""" +A module containing deprecated matrix mixin classes. + +The classes in this module are deprecated and will be removed in a future +release. They are kept here for backwards compatibility in case downstream +code was subclassing them. + +Importing anything else from this module is deprecated so anything here +should either not be used or should be imported from somewhere else. +""" +from __future__ import annotations +from collections import defaultdict +from collections.abc import Iterable +from inspect import isfunction +from functools import reduce + +from sympy.assumptions.refine import refine +from sympy.core import SympifyError, Add +from sympy.core.basic import Atom +from sympy.core.decorators import call_highest_priority +from sympy.core.logic import fuzzy_and, FuzzyBool +from sympy.core.numbers import Integer +from sympy.core.mod import Mod +from sympy.core.singleton import S +from sympy.core.symbol import Symbol +from sympy.core.sympify import sympify +from sympy.functions.elementary.complexes import Abs, re, im +from sympy.utilities.exceptions import sympy_deprecation_warning +from .utilities import _dotprodsimp, _simplify +from sympy.polys.polytools import Poly +from sympy.utilities.iterables import flatten, is_sequence +from sympy.utilities.misc import as_int, filldedent +from sympy.tensor.array import NDimArray + +from .utilities import _get_intermediate_simp_bool + + +# These exception types were previously defined in this module but were moved +# to exceptions.py. We reimport them here for backwards compatibility in case +# downstream code was importing them from here. +from .exceptions import ( # noqa: F401 + MatrixError, ShapeError, NonSquareMatrixError, NonInvertibleMatrixError, + NonPositiveDefiniteMatrixError +) + + +_DEPRECATED_MIXINS = ( + 'MatrixShaping', + 'MatrixSpecial', + 'MatrixProperties', + 'MatrixOperations', + 'MatrixArithmetic', + 'MatrixCommon', + 'MatrixDeterminant', + 'MatrixReductions', + 'MatrixSubspaces', + 'MatrixEigen', + 'MatrixCalculus', + 'MatrixDeprecated', +) + + +class _MatrixDeprecatedMeta(type): + + # + # Override the default __instancecheck__ implementation to ensure that + # e.g. isinstance(M, MatrixCommon) still works when M is one of the + # matrix classes. Matrix no longer inherits from MatrixCommon so + # isinstance(M, MatrixCommon) would now return False by default. + # + # There were lots of places in the codebase where this was being done + # so it seems likely that downstream code may be doing it too. All use + # of these mixins is deprecated though so we give a deprecation warning + # unconditionally if they are being used with isinstance. + # + # Any code seeing this deprecation warning should be changed to use + # isinstance(M, MatrixBase) instead which also works in previous versions + # of SymPy. + # + + def __instancecheck__(cls, instance): + + sympy_deprecation_warning( + f""" + Checking whether an object is an instance of {cls.__name__} is + deprecated. + + Use `isinstance(obj, Matrix)` instead of `isinstance(obj, {cls.__name__})`. + """, + deprecated_since_version="1.13", + active_deprecations_target="deprecated-matrix-mixins", + stacklevel=3, + ) + + from sympy.matrices.matrixbase import MatrixBase + from sympy.matrices.matrices import ( + MatrixDeterminant, + MatrixReductions, + MatrixSubspaces, + MatrixEigen, + MatrixCalculus, + MatrixDeprecated + ) + + all_mixins = ( + MatrixRequired, + MatrixShaping, + MatrixSpecial, + MatrixProperties, + MatrixOperations, + MatrixArithmetic, + MatrixCommon, + MatrixDeterminant, + MatrixReductions, + MatrixSubspaces, + MatrixEigen, + MatrixCalculus, + MatrixDeprecated + ) + + if cls in all_mixins and isinstance(instance, MatrixBase): + return True + else: + return super().__instancecheck__(instance) + + +class MatrixRequired(metaclass=_MatrixDeprecatedMeta): + """Deprecated mixin class for making matrix classes.""" + + rows: int + cols: int + _simplify = None + + def __init_subclass__(cls, **kwargs): + + # Warn if any downstream code is subclassing this class or any of the + # deprecated mixin classes that are all ultimately subclasses of this + # class. + # + # We don't want to warn about the deprecated mixins themselves being + # created, but only about them being used as mixins by downstream code. + # Otherwise just importing this module would trigger a warning. + # Ultimately the whole module should be deprecated and removed but for + # SymPy 1.13 it is premature to do that given that this module was the + # main way to import matrix exception types in all previous versions. + + if cls.__name__ not in _DEPRECATED_MIXINS: + sympy_deprecation_warning( + f""" + Inheriting from the Matrix mixin classes is deprecated. + + The class {cls.__name__} is subclassing a deprecated mixin. + """, + deprecated_since_version="1.13", + active_deprecations_target="deprecated-matrix-mixins", + stacklevel=3, + ) + + super().__init_subclass__(**kwargs) + + @classmethod + def _new(cls, *args, **kwargs): + """`_new` must, at minimum, be callable as + `_new(rows, cols, mat) where mat is a flat list of the + elements of the matrix.""" + raise NotImplementedError("Subclasses must implement this.") + + def __eq__(self, other): + raise NotImplementedError("Subclasses must implement this.") + + def __getitem__(self, key): + """Implementations of __getitem__ should accept ints, in which + case the matrix is indexed as a flat list, tuples (i,j) in which + case the (i,j) entry is returned, slices, or mixed tuples (a,b) + where a and b are any combination of slices and integers.""" + raise NotImplementedError("Subclasses must implement this.") + + def __len__(self): + """The total number of entries in the matrix.""" + raise NotImplementedError("Subclasses must implement this.") + + @property + def shape(self): + raise NotImplementedError("Subclasses must implement this.") + + +class MatrixShaping(MatrixRequired): + """Provides basic matrix shaping and extracting of submatrices""" + + def _eval_col_del(self, col): + def entry(i, j): + return self[i, j] if j < col else self[i, j + 1] + return self._new(self.rows, self.cols - 1, entry) + + def _eval_col_insert(self, pos, other): + + def entry(i, j): + if j < pos: + return self[i, j] + elif pos <= j < pos + other.cols: + return other[i, j - pos] + return self[i, j - other.cols] + + return self._new(self.rows, self.cols + other.cols, entry) + + def _eval_col_join(self, other): + rows = self.rows + + def entry(i, j): + if i < rows: + return self[i, j] + return other[i - rows, j] + + return classof(self, other)._new(self.rows + other.rows, self.cols, + entry) + + def _eval_extract(self, rowsList, colsList): + mat = list(self) + cols = self.cols + indices = (i * cols + j for i in rowsList for j in colsList) + return self._new(len(rowsList), len(colsList), + [mat[i] for i in indices]) + + def _eval_get_diag_blocks(self): + sub_blocks = [] + + def recurse_sub_blocks(M): + for i in range(1, M.shape[0] + 1): + if i == 1: + to_the_right = M[0, i:] + to_the_bottom = M[i:, 0] + else: + to_the_right = M[:i, i:] + to_the_bottom = M[i:, :i] + if any(to_the_right) or any(to_the_bottom): + continue + sub_blocks.append(M[:i, :i]) + if M.shape != M[:i, :i].shape: + recurse_sub_blocks(M[i:, i:]) + return + + recurse_sub_blocks(self) + return sub_blocks + + def _eval_row_del(self, row): + def entry(i, j): + return self[i, j] if i < row else self[i + 1, j] + return self._new(self.rows - 1, self.cols, entry) + + def _eval_row_insert(self, pos, other): + entries = list(self) + insert_pos = pos * self.cols + entries[insert_pos:insert_pos] = list(other) + return self._new(self.rows + other.rows, self.cols, entries) + + def _eval_row_join(self, other): + cols = self.cols + + def entry(i, j): + if j < cols: + return self[i, j] + return other[i, j - cols] + + return classof(self, other)._new(self.rows, self.cols + other.cols, + entry) + + def _eval_tolist(self): + return [list(self[i,:]) for i in range(self.rows)] + + def _eval_todok(self): + dok = {} + rows, cols = self.shape + for i in range(rows): + for j in range(cols): + val = self[i, j] + if val != self.zero: + dok[i, j] = val + return dok + + def _eval_vec(self): + rows = self.rows + + def entry(n, _): + # we want to read off the columns first + j = n // rows + i = n - j * rows + return self[i, j] + + return self._new(len(self), 1, entry) + + def _eval_vech(self, diagonal): + c = self.cols + v = [] + if diagonal: + for j in range(c): + for i in range(j, c): + v.append(self[i, j]) + else: + for j in range(c): + for i in range(j + 1, c): + v.append(self[i, j]) + return self._new(len(v), 1, v) + + def col_del(self, col): + """Delete the specified column.""" + if col < 0: + col += self.cols + if not 0 <= col < self.cols: + raise IndexError("Column {} is out of range.".format(col)) + return self._eval_col_del(col) + + def col_insert(self, pos, other): + """Insert one or more columns at the given column position. + + Examples + ======== + + >>> from sympy import zeros, ones + >>> M = zeros(3) + >>> V = ones(3, 1) + >>> M.col_insert(1, V) + Matrix([ + [0, 1, 0, 0], + [0, 1, 0, 0], + [0, 1, 0, 0]]) + + See Also + ======== + + col + row_insert + """ + # Allows you to build a matrix even if it is null matrix + if not self: + return type(self)(other) + + pos = as_int(pos) + + if pos < 0: + pos = self.cols + pos + if pos < 0: + pos = 0 + elif pos > self.cols: + pos = self.cols + + if self.rows != other.rows: + raise ShapeError( + "The matrices have incompatible number of rows ({} and {})" + .format(self.rows, other.rows)) + + return self._eval_col_insert(pos, other) + + def col_join(self, other): + """Concatenates two matrices along self's last and other's first row. + + Examples + ======== + + >>> from sympy import zeros, ones + >>> M = zeros(3) + >>> V = ones(1, 3) + >>> M.col_join(V) + Matrix([ + [0, 0, 0], + [0, 0, 0], + [0, 0, 0], + [1, 1, 1]]) + + See Also + ======== + + col + row_join + """ + # A null matrix can always be stacked (see #10770) + if self.rows == 0 and self.cols != other.cols: + return self._new(0, other.cols, []).col_join(other) + + if self.cols != other.cols: + raise ShapeError( + "The matrices have incompatible number of columns ({} and {})" + .format(self.cols, other.cols)) + return self._eval_col_join(other) + + def col(self, j): + """Elementary column selector. + + Examples + ======== + + >>> from sympy import eye + >>> eye(2).col(0) + Matrix([ + [1], + [0]]) + + See Also + ======== + + row + col_del + col_join + col_insert + """ + return self[:, j] + + def extract(self, rowsList, colsList): + r"""Return a submatrix by specifying a list of rows and columns. + Negative indices can be given. All indices must be in the range + $-n \le i < n$ where $n$ is the number of rows or columns. + + Examples + ======== + + >>> from sympy import Matrix + >>> m = Matrix(4, 3, range(12)) + >>> m + Matrix([ + [0, 1, 2], + [3, 4, 5], + [6, 7, 8], + [9, 10, 11]]) + >>> m.extract([0, 1, 3], [0, 1]) + Matrix([ + [0, 1], + [3, 4], + [9, 10]]) + + Rows or columns can be repeated: + + >>> m.extract([0, 0, 1], [-1]) + Matrix([ + [2], + [2], + [5]]) + + Every other row can be taken by using range to provide the indices: + + >>> m.extract(range(0, m.rows, 2), [-1]) + Matrix([ + [2], + [8]]) + + RowsList or colsList can also be a list of booleans, in which case + the rows or columns corresponding to the True values will be selected: + + >>> m.extract([0, 1, 2, 3], [True, False, True]) + Matrix([ + [0, 2], + [3, 5], + [6, 8], + [9, 11]]) + """ + + if not is_sequence(rowsList) or not is_sequence(colsList): + raise TypeError("rowsList and colsList must be iterable") + # ensure rowsList and colsList are lists of integers + if rowsList and all(isinstance(i, bool) for i in rowsList): + rowsList = [index for index, item in enumerate(rowsList) if item] + if colsList and all(isinstance(i, bool) for i in colsList): + colsList = [index for index, item in enumerate(colsList) if item] + + # ensure everything is in range + rowsList = [a2idx(k, self.rows) for k in rowsList] + colsList = [a2idx(k, self.cols) for k in colsList] + + return self._eval_extract(rowsList, colsList) + + def get_diag_blocks(self): + """Obtains the square sub-matrices on the main diagonal of a square matrix. + + Useful for inverting symbolic matrices or solving systems of + linear equations which may be decoupled by having a block diagonal + structure. + + Examples + ======== + + >>> from sympy import Matrix + >>> from sympy.abc import x, y, z + >>> A = Matrix([[1, 3, 0, 0], [y, z*z, 0, 0], [0, 0, x, 0], [0, 0, 0, 0]]) + >>> a1, a2, a3 = A.get_diag_blocks() + >>> a1 + Matrix([ + [1, 3], + [y, z**2]]) + >>> a2 + Matrix([[x]]) + >>> a3 + Matrix([[0]]) + + """ + return self._eval_get_diag_blocks() + + @classmethod + def hstack(cls, *args): + """Return a matrix formed by joining args horizontally (i.e. + by repeated application of row_join). + + Examples + ======== + + >>> from sympy import Matrix, eye + >>> Matrix.hstack(eye(2), 2*eye(2)) + Matrix([ + [1, 0, 2, 0], + [0, 1, 0, 2]]) + """ + if len(args) == 0: + return cls._new() + + kls = type(args[0]) + return reduce(kls.row_join, args) + + def reshape(self, rows, cols): + """Reshape the matrix. Total number of elements must remain the same. + + Examples + ======== + + >>> from sympy import Matrix + >>> m = Matrix(2, 3, lambda i, j: 1) + >>> m + Matrix([ + [1, 1, 1], + [1, 1, 1]]) + >>> m.reshape(1, 6) + Matrix([[1, 1, 1, 1, 1, 1]]) + >>> m.reshape(3, 2) + Matrix([ + [1, 1], + [1, 1], + [1, 1]]) + + """ + if self.rows * self.cols != rows * cols: + raise ValueError("Invalid reshape parameters %d %d" % (rows, cols)) + return self._new(rows, cols, lambda i, j: self[i * cols + j]) + + def row_del(self, row): + """Delete the specified row.""" + if row < 0: + row += self.rows + if not 0 <= row < self.rows: + raise IndexError("Row {} is out of range.".format(row)) + + return self._eval_row_del(row) + + def row_insert(self, pos, other): + """Insert one or more rows at the given row position. + + Examples + ======== + + >>> from sympy import zeros, ones + >>> M = zeros(3) + >>> V = ones(1, 3) + >>> M.row_insert(1, V) + Matrix([ + [0, 0, 0], + [1, 1, 1], + [0, 0, 0], + [0, 0, 0]]) + + See Also + ======== + + row + col_insert + """ + # Allows you to build a matrix even if it is null matrix + if not self: + return self._new(other) + + pos = as_int(pos) + + if pos < 0: + pos = self.rows + pos + if pos < 0: + pos = 0 + elif pos > self.rows: + pos = self.rows + + if self.cols != other.cols: + raise ShapeError( + "The matrices have incompatible number of columns ({} and {})" + .format(self.cols, other.cols)) + + return self._eval_row_insert(pos, other) + + def row_join(self, other): + """Concatenates two matrices along self's last and rhs's first column + + Examples + ======== + + >>> from sympy import zeros, ones + >>> M = zeros(3) + >>> V = ones(3, 1) + >>> M.row_join(V) + Matrix([ + [0, 0, 0, 1], + [0, 0, 0, 1], + [0, 0, 0, 1]]) + + See Also + ======== + + row + col_join + """ + # A null matrix can always be stacked (see #10770) + if self.cols == 0 and self.rows != other.rows: + return self._new(other.rows, 0, []).row_join(other) + + if self.rows != other.rows: + raise ShapeError( + "The matrices have incompatible number of rows ({} and {})" + .format(self.rows, other.rows)) + return self._eval_row_join(other) + + def diagonal(self, k=0): + """Returns the kth diagonal of self. The main diagonal + corresponds to `k=0`; diagonals above and below correspond to + `k > 0` and `k < 0`, respectively. The values of `self[i, j]` + for which `j - i = k`, are returned in order of increasing + `i + j`, starting with `i + j = |k|`. + + Examples + ======== + + >>> from sympy import Matrix + >>> m = Matrix(3, 3, lambda i, j: j - i); m + Matrix([ + [ 0, 1, 2], + [-1, 0, 1], + [-2, -1, 0]]) + >>> _.diagonal() + Matrix([[0, 0, 0]]) + >>> m.diagonal(1) + Matrix([[1, 1]]) + >>> m.diagonal(-2) + Matrix([[-2]]) + + Even though the diagonal is returned as a Matrix, the element + retrieval can be done with a single index: + + >>> Matrix.diag(1, 2, 3).diagonal()[1] # instead of [0, 1] + 2 + + See Also + ======== + + diag + """ + rv = [] + k = as_int(k) + r = 0 if k > 0 else -k + c = 0 if r else k + while True: + if r == self.rows or c == self.cols: + break + rv.append(self[r, c]) + r += 1 + c += 1 + if not rv: + raise ValueError(filldedent(''' + The %s diagonal is out of range [%s, %s]''' % ( + k, 1 - self.rows, self.cols - 1))) + return self._new(1, len(rv), rv) + + def row(self, i): + """Elementary row selector. + + Examples + ======== + + >>> from sympy import eye + >>> eye(2).row(0) + Matrix([[1, 0]]) + + See Also + ======== + + col + row_del + row_join + row_insert + """ + return self[i, :] + + @property + def shape(self): + """The shape (dimensions) of the matrix as the 2-tuple (rows, cols). + + Examples + ======== + + >>> from sympy import zeros + >>> M = zeros(2, 3) + >>> M.shape + (2, 3) + >>> M.rows + 2 + >>> M.cols + 3 + """ + return (self.rows, self.cols) + + def todok(self): + """Return the matrix as dictionary of keys. + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix.eye(3) + >>> M.todok() + {(0, 0): 1, (1, 1): 1, (2, 2): 1} + """ + return self._eval_todok() + + def tolist(self): + """Return the Matrix as a nested Python list. + + Examples + ======== + + >>> from sympy import Matrix, ones + >>> m = Matrix(3, 3, range(9)) + >>> m + Matrix([ + [0, 1, 2], + [3, 4, 5], + [6, 7, 8]]) + >>> m.tolist() + [[0, 1, 2], [3, 4, 5], [6, 7, 8]] + >>> ones(3, 0).tolist() + [[], [], []] + + When there are no rows then it will not be possible to tell how + many columns were in the original matrix: + + >>> ones(0, 3).tolist() + [] + + """ + if not self.rows: + return [] + if not self.cols: + return [[] for i in range(self.rows)] + return self._eval_tolist() + + def todod(M): + """Returns matrix as dict of dicts containing non-zero elements of the Matrix + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix([[0, 1],[0, 3]]) + >>> A + Matrix([ + [0, 1], + [0, 3]]) + >>> A.todod() + {0: {1: 1}, 1: {1: 3}} + + + """ + rowsdict = {} + Mlol = M.tolist() + for i, Mi in enumerate(Mlol): + row = {j: Mij for j, Mij in enumerate(Mi) if Mij} + if row: + rowsdict[i] = row + return rowsdict + + def vec(self): + """Return the Matrix converted into a one column matrix by stacking columns + + Examples + ======== + + >>> from sympy import Matrix + >>> m=Matrix([[1, 3], [2, 4]]) + >>> m + Matrix([ + [1, 3], + [2, 4]]) + >>> m.vec() + Matrix([ + [1], + [2], + [3], + [4]]) + + See Also + ======== + + vech + """ + return self._eval_vec() + + def vech(self, diagonal=True, check_symmetry=True): + """Reshapes the matrix into a column vector by stacking the + elements in the lower triangle. + + Parameters + ========== + + diagonal : bool, optional + If ``True``, it includes the diagonal elements. + + check_symmetry : bool, optional + If ``True``, it checks whether the matrix is symmetric. + + Examples + ======== + + >>> from sympy import Matrix + >>> m=Matrix([[1, 2], [2, 3]]) + >>> m + Matrix([ + [1, 2], + [2, 3]]) + >>> m.vech() + Matrix([ + [1], + [2], + [3]]) + >>> m.vech(diagonal=False) + Matrix([[2]]) + + Notes + ===== + + This should work for symmetric matrices and ``vech`` can + represent symmetric matrices in vector form with less size than + ``vec``. + + See Also + ======== + + vec + """ + if not self.is_square: + raise NonSquareMatrixError + + if check_symmetry and not self.is_symmetric(): + raise ValueError("The matrix is not symmetric.") + + return self._eval_vech(diagonal) + + @classmethod + def vstack(cls, *args): + """Return a matrix formed by joining args vertically (i.e. + by repeated application of col_join). + + Examples + ======== + + >>> from sympy import Matrix, eye + >>> Matrix.vstack(eye(2), 2*eye(2)) + Matrix([ + [1, 0], + [0, 1], + [2, 0], + [0, 2]]) + """ + if len(args) == 0: + return cls._new() + + kls = type(args[0]) + return reduce(kls.col_join, args) + + +class MatrixSpecial(MatrixRequired): + """Construction of special matrices""" + + @classmethod + def _eval_diag(cls, rows, cols, diag_dict): + """diag_dict is a defaultdict containing + all the entries of the diagonal matrix.""" + def entry(i, j): + return diag_dict[(i, j)] + return cls._new(rows, cols, entry) + + @classmethod + def _eval_eye(cls, rows, cols): + vals = [cls.zero]*(rows*cols) + vals[::cols+1] = [cls.one]*min(rows, cols) + return cls._new(rows, cols, vals, copy=False) + + @classmethod + def _eval_jordan_block(cls, size: int, eigenvalue, band='upper'): + if band == 'lower': + def entry(i, j): + if i == j: + return eigenvalue + elif j + 1 == i: + return cls.one + return cls.zero + else: + def entry(i, j): + if i == j: + return eigenvalue + elif i + 1 == j: + return cls.one + return cls.zero + return cls._new(size, size, entry) + + @classmethod + def _eval_ones(cls, rows, cols): + def entry(i, j): + return cls.one + return cls._new(rows, cols, entry) + + @classmethod + def _eval_zeros(cls, rows, cols): + return cls._new(rows, cols, [cls.zero]*(rows*cols), copy=False) + + @classmethod + def _eval_wilkinson(cls, n): + def entry(i, j): + return cls.one if i + 1 == j else cls.zero + + D = cls._new(2*n + 1, 2*n + 1, entry) + + wminus = cls.diag(list(range(-n, n + 1)), unpack=True) + D + D.T + wplus = abs(cls.diag(list(range(-n, n + 1)), unpack=True)) + D + D.T + + return wminus, wplus + + @classmethod + def diag(kls, *args, strict=False, unpack=True, rows=None, cols=None, **kwargs): + """Returns a matrix with the specified diagonal. + If matrices are passed, a block-diagonal matrix + is created (i.e. the "direct sum" of the matrices). + + kwargs + ====== + + rows : rows of the resulting matrix; computed if + not given. + + cols : columns of the resulting matrix; computed if + not given. + + cls : class for the resulting matrix + + unpack : bool which, when True (default), unpacks a single + sequence rather than interpreting it as a Matrix. + + strict : bool which, when False (default), allows Matrices to + have variable-length rows. + + Examples + ======== + + >>> from sympy import Matrix + >>> Matrix.diag(1, 2, 3) + Matrix([ + [1, 0, 0], + [0, 2, 0], + [0, 0, 3]]) + + The current default is to unpack a single sequence. If this is + not desired, set `unpack=False` and it will be interpreted as + a matrix. + + >>> Matrix.diag([1, 2, 3]) == Matrix.diag(1, 2, 3) + True + + When more than one element is passed, each is interpreted as + something to put on the diagonal. Lists are converted to + matrices. Filling of the diagonal always continues from + the bottom right hand corner of the previous item: this + will create a block-diagonal matrix whether the matrices + are square or not. + + >>> col = [1, 2, 3] + >>> row = [[4, 5]] + >>> Matrix.diag(col, row) + Matrix([ + [1, 0, 0], + [2, 0, 0], + [3, 0, 0], + [0, 4, 5]]) + + When `unpack` is False, elements within a list need not all be + of the same length. Setting `strict` to True would raise a + ValueError for the following: + + >>> Matrix.diag([[1, 2, 3], [4, 5], [6]], unpack=False) + Matrix([ + [1, 2, 3], + [4, 5, 0], + [6, 0, 0]]) + + The type of the returned matrix can be set with the ``cls`` + keyword. + + >>> from sympy import ImmutableMatrix + >>> from sympy.utilities.misc import func_name + >>> func_name(Matrix.diag(1, cls=ImmutableMatrix)) + 'ImmutableDenseMatrix' + + A zero dimension matrix can be used to position the start of + the filling at the start of an arbitrary row or column: + + >>> from sympy import ones + >>> r2 = ones(0, 2) + >>> Matrix.diag(r2, 1, 2) + Matrix([ + [0, 0, 1, 0], + [0, 0, 0, 2]]) + + See Also + ======== + eye + diagonal + .dense.diag + .expressions.blockmatrix.BlockMatrix + .sparsetools.banded + """ + from sympy.matrices.matrixbase import MatrixBase + from sympy.matrices.dense import Matrix + from sympy.matrices import SparseMatrix + klass = kwargs.get('cls', kls) + if unpack and len(args) == 1 and is_sequence(args[0]) and \ + not isinstance(args[0], MatrixBase): + args = args[0] + + # fill a default dict with the diagonal entries + diag_entries = defaultdict(int) + rmax = cmax = 0 # keep track of the biggest index seen + for m in args: + if isinstance(m, list): + if strict: + # if malformed, Matrix will raise an error + _ = Matrix(m) + r, c = _.shape + m = _.tolist() + else: + r, c, smat = SparseMatrix._handle_creation_inputs(m) + for (i, j), _ in smat.items(): + diag_entries[(i + rmax, j + cmax)] = _ + m = [] # to skip process below + elif hasattr(m, 'shape'): # a Matrix + # convert to list of lists + r, c = m.shape + m = m.tolist() + else: # in this case, we're a single value + diag_entries[(rmax, cmax)] = m + rmax += 1 + cmax += 1 + continue + # process list of lists + for i, mi in enumerate(m): + for j, _ in enumerate(mi): + diag_entries[(i + rmax, j + cmax)] = _ + rmax += r + cmax += c + if rows is None: + rows, cols = cols, rows + if rows is None: + rows, cols = rmax, cmax + else: + cols = rows if cols is None else cols + if rows < rmax or cols < cmax: + raise ValueError(filldedent(''' + The constructed matrix is {} x {} but a size of {} x {} + was specified.'''.format(rmax, cmax, rows, cols))) + return klass._eval_diag(rows, cols, diag_entries) + + @classmethod + def eye(kls, rows, cols=None, **kwargs): + """Returns an identity matrix. + + Parameters + ========== + + rows : rows of the matrix + cols : cols of the matrix (if None, cols=rows) + + kwargs + ====== + cls : class of the returned matrix + """ + if cols is None: + cols = rows + if rows < 0 or cols < 0: + raise ValueError("Cannot create a {} x {} matrix. " + "Both dimensions must be positive".format(rows, cols)) + klass = kwargs.get('cls', kls) + rows, cols = as_int(rows), as_int(cols) + + return klass._eval_eye(rows, cols) + + @classmethod + def jordan_block(kls, size=None, eigenvalue=None, *, band='upper', **kwargs): + """Returns a Jordan block + + Parameters + ========== + + size : Integer, optional + Specifies the shape of the Jordan block matrix. + + eigenvalue : Number or Symbol + Specifies the value for the main diagonal of the matrix. + + .. note:: + The keyword ``eigenval`` is also specified as an alias + of this keyword, but it is not recommended to use. + + We may deprecate the alias in later release. + + band : 'upper' or 'lower', optional + Specifies the position of the off-diagonal to put `1` s on. + + cls : Matrix, optional + Specifies the matrix class of the output form. + + If it is not specified, the class type where the method is + being executed on will be returned. + + Returns + ======= + + Matrix + A Jordan block matrix. + + Raises + ====== + + ValueError + If insufficient arguments are given for matrix size + specification, or no eigenvalue is given. + + Examples + ======== + + Creating a default Jordan block: + + >>> from sympy import Matrix + >>> from sympy.abc import x + >>> Matrix.jordan_block(4, x) + Matrix([ + [x, 1, 0, 0], + [0, x, 1, 0], + [0, 0, x, 1], + [0, 0, 0, x]]) + + Creating an alternative Jordan block matrix where `1` is on + lower off-diagonal: + + >>> Matrix.jordan_block(4, x, band='lower') + Matrix([ + [x, 0, 0, 0], + [1, x, 0, 0], + [0, 1, x, 0], + [0, 0, 1, x]]) + + Creating a Jordan block with keyword arguments + + >>> Matrix.jordan_block(size=4, eigenvalue=x) + Matrix([ + [x, 1, 0, 0], + [0, x, 1, 0], + [0, 0, x, 1], + [0, 0, 0, x]]) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Jordan_matrix + """ + klass = kwargs.pop('cls', kls) + + eigenval = kwargs.get('eigenval', None) + if eigenvalue is None and eigenval is None: + raise ValueError("Must supply an eigenvalue") + elif eigenvalue != eigenval and None not in (eigenval, eigenvalue): + raise ValueError( + "Inconsistent values are given: 'eigenval'={}, " + "'eigenvalue'={}".format(eigenval, eigenvalue)) + else: + if eigenval is not None: + eigenvalue = eigenval + + if size is None: + raise ValueError("Must supply a matrix size") + + size = as_int(size) + return klass._eval_jordan_block(size, eigenvalue, band) + + @classmethod + def ones(kls, rows, cols=None, **kwargs): + """Returns a matrix of ones. + + Parameters + ========== + + rows : rows of the matrix + cols : cols of the matrix (if None, cols=rows) + + kwargs + ====== + cls : class of the returned matrix + """ + if cols is None: + cols = rows + klass = kwargs.get('cls', kls) + rows, cols = as_int(rows), as_int(cols) + + return klass._eval_ones(rows, cols) + + @classmethod + def zeros(kls, rows, cols=None, **kwargs): + """Returns a matrix of zeros. + + Parameters + ========== + + rows : rows of the matrix + cols : cols of the matrix (if None, cols=rows) + + kwargs + ====== + cls : class of the returned matrix + """ + if cols is None: + cols = rows + if rows < 0 or cols < 0: + raise ValueError("Cannot create a {} x {} matrix. " + "Both dimensions must be positive".format(rows, cols)) + klass = kwargs.get('cls', kls) + rows, cols = as_int(rows), as_int(cols) + + return klass._eval_zeros(rows, cols) + + @classmethod + def companion(kls, poly): + """Returns a companion matrix of a polynomial. + + Examples + ======== + + >>> from sympy import Matrix, Poly, Symbol, symbols + >>> x = Symbol('x') + >>> c0, c1, c2, c3, c4 = symbols('c0:5') + >>> p = Poly(c0 + c1*x + c2*x**2 + c3*x**3 + c4*x**4 + x**5, x) + >>> Matrix.companion(p) + Matrix([ + [0, 0, 0, 0, -c0], + [1, 0, 0, 0, -c1], + [0, 1, 0, 0, -c2], + [0, 0, 1, 0, -c3], + [0, 0, 0, 1, -c4]]) + """ + poly = kls._sympify(poly) + if not isinstance(poly, Poly): + raise ValueError("{} must be a Poly instance.".format(poly)) + if not poly.is_monic: + raise ValueError("{} must be a monic polynomial.".format(poly)) + if not poly.is_univariate: + raise ValueError( + "{} must be a univariate polynomial.".format(poly)) + + size = poly.degree() + if not size >= 1: + raise ValueError( + "{} must have degree not less than 1.".format(poly)) + + coeffs = poly.all_coeffs() + def entry(i, j): + if j == size - 1: + return -coeffs[-1 - i] + elif i == j + 1: + return kls.one + return kls.zero + return kls._new(size, size, entry) + + + @classmethod + def wilkinson(kls, n, **kwargs): + """Returns two square Wilkinson Matrix of size 2*n + 1 + $W_{2n + 1}^-, W_{2n + 1}^+ =$ Wilkinson(n) + + Examples + ======== + + >>> from sympy import Matrix + >>> wminus, wplus = Matrix.wilkinson(3) + >>> wminus + Matrix([ + [-3, 1, 0, 0, 0, 0, 0], + [ 1, -2, 1, 0, 0, 0, 0], + [ 0, 1, -1, 1, 0, 0, 0], + [ 0, 0, 1, 0, 1, 0, 0], + [ 0, 0, 0, 1, 1, 1, 0], + [ 0, 0, 0, 0, 1, 2, 1], + [ 0, 0, 0, 0, 0, 1, 3]]) + >>> wplus + Matrix([ + [3, 1, 0, 0, 0, 0, 0], + [1, 2, 1, 0, 0, 0, 0], + [0, 1, 1, 1, 0, 0, 0], + [0, 0, 1, 0, 1, 0, 0], + [0, 0, 0, 1, 1, 1, 0], + [0, 0, 0, 0, 1, 2, 1], + [0, 0, 0, 0, 0, 1, 3]]) + + References + ========== + + .. [1] https://blogs.mathworks.com/cleve/2013/04/15/wilkinsons-matrices-2/ + .. [2] J. H. Wilkinson, The Algebraic Eigenvalue Problem, Claredon Press, Oxford, 1965, 662 pp. + + """ + klass = kwargs.get('cls', kls) + n = as_int(n) + return klass._eval_wilkinson(n) + +class MatrixProperties(MatrixRequired): + """Provides basic properties of a matrix.""" + + def _eval_atoms(self, *types): + result = set() + for i in self: + result.update(i.atoms(*types)) + return result + + def _eval_free_symbols(self): + return set().union(*(i.free_symbols for i in self if i)) + + def _eval_has(self, *patterns): + return any(a.has(*patterns) for a in self) + + def _eval_is_anti_symmetric(self, simpfunc): + if not all(simpfunc(self[i, j] + self[j, i]).is_zero for i in range(self.rows) for j in range(self.cols)): + return False + return True + + def _eval_is_diagonal(self): + for i in range(self.rows): + for j in range(self.cols): + if i != j and self[i, j]: + return False + return True + + # _eval_is_hermitian is called by some general SymPy + # routines and has a different *args signature. Make + # sure the names don't clash by adding `_matrix_` in name. + def _eval_is_matrix_hermitian(self, simpfunc): + mat = self._new(self.rows, self.cols, lambda i, j: simpfunc(self[i, j] - self[j, i].conjugate())) + return mat.is_zero_matrix + + def _eval_is_Identity(self) -> FuzzyBool: + def dirac(i, j): + if i == j: + return 1 + return 0 + + return all(self[i, j] == dirac(i, j) + for i in range(self.rows) + for j in range(self.cols)) + + def _eval_is_lower_hessenberg(self): + return all(self[i, j].is_zero + for i in range(self.rows) + for j in range(i + 2, self.cols)) + + def _eval_is_lower(self): + return all(self[i, j].is_zero + for i in range(self.rows) + for j in range(i + 1, self.cols)) + + def _eval_is_symbolic(self): + return self.has(Symbol) + + def _eval_is_symmetric(self, simpfunc): + mat = self._new(self.rows, self.cols, lambda i, j: simpfunc(self[i, j] - self[j, i])) + return mat.is_zero_matrix + + def _eval_is_zero_matrix(self): + if any(i.is_zero == False for i in self): + return False + if any(i.is_zero is None for i in self): + return None + return True + + def _eval_is_upper_hessenberg(self): + return all(self[i, j].is_zero + for i in range(2, self.rows) + for j in range(min(self.cols, (i - 1)))) + + def _eval_values(self): + return [i for i in self if not i.is_zero] + + def _has_positive_diagonals(self): + diagonal_entries = (self[i, i] for i in range(self.rows)) + return fuzzy_and(x.is_positive for x in diagonal_entries) + + def _has_nonnegative_diagonals(self): + diagonal_entries = (self[i, i] for i in range(self.rows)) + return fuzzy_and(x.is_nonnegative for x in diagonal_entries) + + def atoms(self, *types): + """Returns the atoms that form the current object. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy import Matrix + >>> Matrix([[x]]) + Matrix([[x]]) + >>> _.atoms() + {x} + >>> Matrix([[x, y], [y, x]]) + Matrix([ + [x, y], + [y, x]]) + >>> _.atoms() + {x, y} + """ + + types = tuple(t if isinstance(t, type) else type(t) for t in types) + if not types: + types = (Atom,) + return self._eval_atoms(*types) + + @property + def free_symbols(self): + """Returns the free symbols within the matrix. + + Examples + ======== + + >>> from sympy.abc import x + >>> from sympy import Matrix + >>> Matrix([[x], [1]]).free_symbols + {x} + """ + return self._eval_free_symbols() + + def has(self, *patterns): + """Test whether any subexpression matches any of the patterns. + + Examples + ======== + + >>> from sympy import Matrix, SparseMatrix, Float + >>> from sympy.abc import x, y + >>> A = Matrix(((1, x), (0.2, 3))) + >>> B = SparseMatrix(((1, x), (0.2, 3))) + >>> A.has(x) + True + >>> A.has(y) + False + >>> A.has(Float) + True + >>> B.has(x) + True + >>> B.has(y) + False + >>> B.has(Float) + True + """ + return self._eval_has(*patterns) + + def is_anti_symmetric(self, simplify=True): + """Check if matrix M is an antisymmetric matrix, + that is, M is a square matrix with all M[i, j] == -M[j, i]. + + When ``simplify=True`` (default), the sum M[i, j] + M[j, i] is + simplified before testing to see if it is zero. By default, + the SymPy simplify function is used. To use a custom function + set simplify to a function that accepts a single argument which + returns a simplified expression. To skip simplification, set + simplify to False but note that although this will be faster, + it may induce false negatives. + + Examples + ======== + + >>> from sympy import Matrix, symbols + >>> m = Matrix(2, 2, [0, 1, -1, 0]) + >>> m + Matrix([ + [ 0, 1], + [-1, 0]]) + >>> m.is_anti_symmetric() + True + >>> x, y = symbols('x y') + >>> m = Matrix(2, 3, [0, 0, x, -y, 0, 0]) + >>> m + Matrix([ + [ 0, 0, x], + [-y, 0, 0]]) + >>> m.is_anti_symmetric() + False + + >>> from sympy.abc import x, y + >>> m = Matrix(3, 3, [0, x**2 + 2*x + 1, y, + ... -(x + 1)**2, 0, x*y, + ... -y, -x*y, 0]) + + Simplification of matrix elements is done by default so even + though two elements which should be equal and opposite would not + pass an equality test, the matrix is still reported as + anti-symmetric: + + >>> m[0, 1] == -m[1, 0] + False + >>> m.is_anti_symmetric() + True + + If ``simplify=False`` is used for the case when a Matrix is already + simplified, this will speed things up. Here, we see that without + simplification the matrix does not appear anti-symmetric: + + >>> print(m.is_anti_symmetric(simplify=False)) + None + + But if the matrix were already expanded, then it would appear + anti-symmetric and simplification in the is_anti_symmetric routine + is not needed: + + >>> m = m.expand() + >>> m.is_anti_symmetric(simplify=False) + True + """ + # accept custom simplification + simpfunc = simplify + if not isfunction(simplify): + simpfunc = _simplify if simplify else lambda x: x + + if not self.is_square: + return False + return self._eval_is_anti_symmetric(simpfunc) + + def is_diagonal(self): + """Check if matrix is diagonal, + that is matrix in which the entries outside the main diagonal are all zero. + + Examples + ======== + + >>> from sympy import Matrix, diag + >>> m = Matrix(2, 2, [1, 0, 0, 2]) + >>> m + Matrix([ + [1, 0], + [0, 2]]) + >>> m.is_diagonal() + True + + >>> m = Matrix(2, 2, [1, 1, 0, 2]) + >>> m + Matrix([ + [1, 1], + [0, 2]]) + >>> m.is_diagonal() + False + + >>> m = diag(1, 2, 3) + >>> m + Matrix([ + [1, 0, 0], + [0, 2, 0], + [0, 0, 3]]) + >>> m.is_diagonal() + True + + See Also + ======== + + is_lower + is_upper + sympy.matrices.matrixbase.MatrixCommon.is_diagonalizable + diagonalize + """ + return self._eval_is_diagonal() + + @property + def is_weakly_diagonally_dominant(self): + r"""Tests if the matrix is row weakly diagonally dominant. + + Explanation + =========== + + A $n, n$ matrix $A$ is row weakly diagonally dominant if + + .. math:: + \left|A_{i, i}\right| \ge \sum_{j = 0, j \neq i}^{n-1} + \left|A_{i, j}\right| \quad {\text{for all }} + i \in \{ 0, ..., n-1 \} + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix([[3, -2, 1], [1, -3, 2], [-1, 2, 4]]) + >>> A.is_weakly_diagonally_dominant + True + + >>> A = Matrix([[-2, 2, 1], [1, 3, 2], [1, -2, 0]]) + >>> A.is_weakly_diagonally_dominant + False + + >>> A = Matrix([[-4, 2, 1], [1, 6, 2], [1, -2, 5]]) + >>> A.is_weakly_diagonally_dominant + True + + Notes + ===== + + If you want to test whether a matrix is column diagonally + dominant, you can apply the test after transposing the matrix. + """ + if not self.is_square: + return False + + rows, cols = self.shape + + def test_row(i): + summation = self.zero + for j in range(cols): + if i != j: + summation += Abs(self[i, j]) + return (Abs(self[i, i]) - summation).is_nonnegative + + return fuzzy_and(test_row(i) for i in range(rows)) + + @property + def is_strongly_diagonally_dominant(self): + r"""Tests if the matrix is row strongly diagonally dominant. + + Explanation + =========== + + A $n, n$ matrix $A$ is row strongly diagonally dominant if + + .. math:: + \left|A_{i, i}\right| > \sum_{j = 0, j \neq i}^{n-1} + \left|A_{i, j}\right| \quad {\text{for all }} + i \in \{ 0, ..., n-1 \} + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix([[3, -2, 1], [1, -3, 2], [-1, 2, 4]]) + >>> A.is_strongly_diagonally_dominant + False + + >>> A = Matrix([[-2, 2, 1], [1, 3, 2], [1, -2, 0]]) + >>> A.is_strongly_diagonally_dominant + False + + >>> A = Matrix([[-4, 2, 1], [1, 6, 2], [1, -2, 5]]) + >>> A.is_strongly_diagonally_dominant + True + + Notes + ===== + + If you want to test whether a matrix is column diagonally + dominant, you can apply the test after transposing the matrix. + """ + if not self.is_square: + return False + + rows, cols = self.shape + + def test_row(i): + summation = self.zero + for j in range(cols): + if i != j: + summation += Abs(self[i, j]) + return (Abs(self[i, i]) - summation).is_positive + + return fuzzy_and(test_row(i) for i in range(rows)) + + @property + def is_hermitian(self): + """Checks if the matrix is Hermitian. + + In a Hermitian matrix element i,j is the complex conjugate of + element j,i. + + Examples + ======== + + >>> from sympy import Matrix + >>> from sympy import I + >>> from sympy.abc import x + >>> a = Matrix([[1, I], [-I, 1]]) + >>> a + Matrix([ + [ 1, I], + [-I, 1]]) + >>> a.is_hermitian + True + >>> a[0, 0] = 2*I + >>> a.is_hermitian + False + >>> a[0, 0] = x + >>> a.is_hermitian + >>> a[0, 1] = a[1, 0]*I + >>> a.is_hermitian + False + """ + if not self.is_square: + return False + + return self._eval_is_matrix_hermitian(_simplify) + + @property + def is_Identity(self) -> FuzzyBool: + if not self.is_square: + return False + return self._eval_is_Identity() + + @property + def is_lower_hessenberg(self): + r"""Checks if the matrix is in the lower-Hessenberg form. + + The lower hessenberg matrix has zero entries + above the first superdiagonal. + + Examples + ======== + + >>> from sympy import Matrix + >>> a = Matrix([[1, 2, 0, 0], [5, 2, 3, 0], [3, 4, 3, 7], [5, 6, 1, 1]]) + >>> a + Matrix([ + [1, 2, 0, 0], + [5, 2, 3, 0], + [3, 4, 3, 7], + [5, 6, 1, 1]]) + >>> a.is_lower_hessenberg + True + + See Also + ======== + + is_upper_hessenberg + is_lower + """ + return self._eval_is_lower_hessenberg() + + @property + def is_lower(self): + """Check if matrix is a lower triangular matrix. True can be returned + even if the matrix is not square. + + Examples + ======== + + >>> from sympy import Matrix + >>> m = Matrix(2, 2, [1, 0, 0, 1]) + >>> m + Matrix([ + [1, 0], + [0, 1]]) + >>> m.is_lower + True + + >>> m = Matrix(4, 3, [0, 0, 0, 2, 0, 0, 1, 4, 0, 6, 6, 5]) + >>> m + Matrix([ + [0, 0, 0], + [2, 0, 0], + [1, 4, 0], + [6, 6, 5]]) + >>> m.is_lower + True + + >>> from sympy.abc import x, y + >>> m = Matrix(2, 2, [x**2 + y, y**2 + x, 0, x + y]) + >>> m + Matrix([ + [x**2 + y, x + y**2], + [ 0, x + y]]) + >>> m.is_lower + False + + See Also + ======== + + is_upper + is_diagonal + is_lower_hessenberg + """ + return self._eval_is_lower() + + @property + def is_square(self): + """Checks if a matrix is square. + + A matrix is square if the number of rows equals the number of columns. + The empty matrix is square by definition, since the number of rows and + the number of columns are both zero. + + Examples + ======== + + >>> from sympy import Matrix + >>> a = Matrix([[1, 2, 3], [4, 5, 6]]) + >>> b = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) + >>> c = Matrix([]) + >>> a.is_square + False + >>> b.is_square + True + >>> c.is_square + True + """ + return self.rows == self.cols + + def is_symbolic(self): + """Checks if any elements contain Symbols. + + Examples + ======== + + >>> from sympy import Matrix + >>> from sympy.abc import x, y + >>> M = Matrix([[x, y], [1, 0]]) + >>> M.is_symbolic() + True + + """ + return self._eval_is_symbolic() + + def is_symmetric(self, simplify=True): + """Check if matrix is symmetric matrix, + that is square matrix and is equal to its transpose. + + By default, simplifications occur before testing symmetry. + They can be skipped using 'simplify=False'; while speeding things a bit, + this may however induce false negatives. + + Examples + ======== + + >>> from sympy import Matrix + >>> m = Matrix(2, 2, [0, 1, 1, 2]) + >>> m + Matrix([ + [0, 1], + [1, 2]]) + >>> m.is_symmetric() + True + + >>> m = Matrix(2, 2, [0, 1, 2, 0]) + >>> m + Matrix([ + [0, 1], + [2, 0]]) + >>> m.is_symmetric() + False + + >>> m = Matrix(2, 3, [0, 0, 0, 0, 0, 0]) + >>> m + Matrix([ + [0, 0, 0], + [0, 0, 0]]) + >>> m.is_symmetric() + False + + >>> from sympy.abc import x, y + >>> m = Matrix(3, 3, [1, x**2 + 2*x + 1, y, (x + 1)**2, 2, 0, y, 0, 3]) + >>> m + Matrix([ + [ 1, x**2 + 2*x + 1, y], + [(x + 1)**2, 2, 0], + [ y, 0, 3]]) + >>> m.is_symmetric() + True + + If the matrix is already simplified, you may speed-up is_symmetric() + test by using 'simplify=False'. + + >>> bool(m.is_symmetric(simplify=False)) + False + >>> m1 = m.expand() + >>> m1.is_symmetric(simplify=False) + True + """ + simpfunc = simplify + if not isfunction(simplify): + simpfunc = _simplify if simplify else lambda x: x + + if not self.is_square: + return False + + return self._eval_is_symmetric(simpfunc) + + @property + def is_upper_hessenberg(self): + """Checks if the matrix is the upper-Hessenberg form. + + The upper hessenberg matrix has zero entries + below the first subdiagonal. + + Examples + ======== + + >>> from sympy import Matrix + >>> a = Matrix([[1, 4, 2, 3], [3, 4, 1, 7], [0, 2, 3, 4], [0, 0, 1, 3]]) + >>> a + Matrix([ + [1, 4, 2, 3], + [3, 4, 1, 7], + [0, 2, 3, 4], + [0, 0, 1, 3]]) + >>> a.is_upper_hessenberg + True + + See Also + ======== + + is_lower_hessenberg + is_upper + """ + return self._eval_is_upper_hessenberg() + + @property + def is_upper(self): + """Check if matrix is an upper triangular matrix. True can be returned + even if the matrix is not square. + + Examples + ======== + + >>> from sympy import Matrix + >>> m = Matrix(2, 2, [1, 0, 0, 1]) + >>> m + Matrix([ + [1, 0], + [0, 1]]) + >>> m.is_upper + True + + >>> m = Matrix(4, 3, [5, 1, 9, 0, 4, 6, 0, 0, 5, 0, 0, 0]) + >>> m + Matrix([ + [5, 1, 9], + [0, 4, 6], + [0, 0, 5], + [0, 0, 0]]) + >>> m.is_upper + True + + >>> m = Matrix(2, 3, [4, 2, 5, 6, 1, 1]) + >>> m + Matrix([ + [4, 2, 5], + [6, 1, 1]]) + >>> m.is_upper + False + + See Also + ======== + + is_lower + is_diagonal + is_upper_hessenberg + """ + return all(self[i, j].is_zero + for i in range(1, self.rows) + for j in range(min(i, self.cols))) + + @property + def is_zero_matrix(self): + """Checks if a matrix is a zero matrix. + + A matrix is zero if every element is zero. A matrix need not be square + to be considered zero. The empty matrix is zero by the principle of + vacuous truth. For a matrix that may or may not be zero (e.g. + contains a symbol), this will be None + + Examples + ======== + + >>> from sympy import Matrix, zeros + >>> from sympy.abc import x + >>> a = Matrix([[0, 0], [0, 0]]) + >>> b = zeros(3, 4) + >>> c = Matrix([[0, 1], [0, 0]]) + >>> d = Matrix([]) + >>> e = Matrix([[x, 0], [0, 0]]) + >>> a.is_zero_matrix + True + >>> b.is_zero_matrix + True + >>> c.is_zero_matrix + False + >>> d.is_zero_matrix + True + >>> e.is_zero_matrix + """ + return self._eval_is_zero_matrix() + + def values(self): + """Return non-zero values of self.""" + return self._eval_values() + + +class MatrixOperations(MatrixRequired): + """Provides basic matrix shape and elementwise + operations. Should not be instantiated directly.""" + + def _eval_adjoint(self): + return self.transpose().conjugate() + + def _eval_applyfunc(self, f): + out = self._new(self.rows, self.cols, [f(x) for x in self]) + return out + + def _eval_as_real_imag(self): # type: ignore + return (self.applyfunc(re), self.applyfunc(im)) + + def _eval_conjugate(self): + return self.applyfunc(lambda x: x.conjugate()) + + def _eval_permute_cols(self, perm): + # apply the permutation to a list + mapping = list(perm) + + def entry(i, j): + return self[i, mapping[j]] + + return self._new(self.rows, self.cols, entry) + + def _eval_permute_rows(self, perm): + # apply the permutation to a list + mapping = list(perm) + + def entry(i, j): + return self[mapping[i], j] + + return self._new(self.rows, self.cols, entry) + + def _eval_trace(self): + return sum(self[i, i] for i in range(self.rows)) + + def _eval_transpose(self): + return self._new(self.cols, self.rows, lambda i, j: self[j, i]) + + def adjoint(self): + """Conjugate transpose or Hermitian conjugation.""" + return self._eval_adjoint() + + def applyfunc(self, f): + """Apply a function to each element of the matrix. + + Examples + ======== + + >>> from sympy import Matrix + >>> m = Matrix(2, 2, lambda i, j: i*2+j) + >>> m + Matrix([ + [0, 1], + [2, 3]]) + >>> m.applyfunc(lambda i: 2*i) + Matrix([ + [0, 2], + [4, 6]]) + + """ + if not callable(f): + raise TypeError("`f` must be callable.") + + return self._eval_applyfunc(f) + + def as_real_imag(self, deep=True, **hints): + """Returns a tuple containing the (real, imaginary) part of matrix.""" + # XXX: Ignoring deep and hints... + return self._eval_as_real_imag() + + def conjugate(self): + """Return the by-element conjugation. + + Examples + ======== + + >>> from sympy import SparseMatrix, I + >>> a = SparseMatrix(((1, 2 + I), (3, 4), (I, -I))) + >>> a + Matrix([ + [1, 2 + I], + [3, 4], + [I, -I]]) + >>> a.C + Matrix([ + [ 1, 2 - I], + [ 3, 4], + [-I, I]]) + + See Also + ======== + + transpose: Matrix transposition + H: Hermite conjugation + sympy.matrices.matrixbase.MatrixBase.D: Dirac conjugation + """ + return self._eval_conjugate() + + def doit(self, **hints): + return self.applyfunc(lambda x: x.doit(**hints)) + + def evalf(self, n=15, subs=None, maxn=100, chop=False, strict=False, quad=None, verbose=False): + """Apply evalf() to each element of self.""" + options = {'subs':subs, 'maxn':maxn, 'chop':chop, 'strict':strict, + 'quad':quad, 'verbose':verbose} + return self.applyfunc(lambda i: i.evalf(n, **options)) + + def expand(self, deep=True, modulus=None, power_base=True, power_exp=True, + mul=True, log=True, multinomial=True, basic=True, **hints): + """Apply core.function.expand to each entry of the matrix. + + Examples + ======== + + >>> from sympy.abc import x + >>> from sympy import Matrix + >>> Matrix(1, 1, [x*(x+1)]) + Matrix([[x*(x + 1)]]) + >>> _.expand() + Matrix([[x**2 + x]]) + + """ + return self.applyfunc(lambda x: x.expand( + deep, modulus, power_base, power_exp, mul, log, multinomial, basic, + **hints)) + + @property + def H(self): + """Return Hermite conjugate. + + Examples + ======== + + >>> from sympy import Matrix, I + >>> m = Matrix((0, 1 + I, 2, 3)) + >>> m + Matrix([ + [ 0], + [1 + I], + [ 2], + [ 3]]) + >>> m.H + Matrix([[0, 1 - I, 2, 3]]) + + See Also + ======== + + conjugate: By-element conjugation + sympy.matrices.matrixbase.MatrixBase.D: Dirac conjugation + """ + return self.T.C + + def permute(self, perm, orientation='rows', direction='forward'): + r"""Permute the rows or columns of a matrix by the given list of + swaps. + + Parameters + ========== + + perm : Permutation, list, or list of lists + A representation for the permutation. + + If it is ``Permutation``, it is used directly with some + resizing with respect to the matrix size. + + If it is specified as list of lists, + (e.g., ``[[0, 1], [0, 2]]``), then the permutation is formed + from applying the product of cycles. The direction how the + cyclic product is applied is described in below. + + If it is specified as a list, the list should represent + an array form of a permutation. (e.g., ``[1, 2, 0]``) which + would would form the swapping function + `0 \mapsto 1, 1 \mapsto 2, 2\mapsto 0`. + + orientation : 'rows', 'cols' + A flag to control whether to permute the rows or the columns + + direction : 'forward', 'backward' + A flag to control whether to apply the permutations from + the start of the list first, or from the back of the list + first. + + For example, if the permutation specification is + ``[[0, 1], [0, 2]]``, + + If the flag is set to ``'forward'``, the cycle would be + formed as `0 \mapsto 2, 2 \mapsto 1, 1 \mapsto 0`. + + If the flag is set to ``'backward'``, the cycle would be + formed as `0 \mapsto 1, 1 \mapsto 2, 2 \mapsto 0`. + + If the argument ``perm`` is not in a form of list of lists, + this flag takes no effect. + + Examples + ======== + + >>> from sympy import eye + >>> M = eye(3) + >>> M.permute([[0, 1], [0, 2]], orientation='rows', direction='forward') + Matrix([ + [0, 0, 1], + [1, 0, 0], + [0, 1, 0]]) + + >>> from sympy import eye + >>> M = eye(3) + >>> M.permute([[0, 1], [0, 2]], orientation='rows', direction='backward') + Matrix([ + [0, 1, 0], + [0, 0, 1], + [1, 0, 0]]) + + Notes + ===== + + If a bijective function + `\sigma : \mathbb{N}_0 \rightarrow \mathbb{N}_0` denotes the + permutation. + + If the matrix `A` is the matrix to permute, represented as + a horizontal or a vertical stack of vectors: + + .. math:: + A = + \begin{bmatrix} + a_0 \\ a_1 \\ \vdots \\ a_{n-1} + \end{bmatrix} = + \begin{bmatrix} + \alpha_0 & \alpha_1 & \cdots & \alpha_{n-1} + \end{bmatrix} + + If the matrix `B` is the result, the permutation of matrix rows + is defined as: + + .. math:: + B := \begin{bmatrix} + a_{\sigma(0)} \\ a_{\sigma(1)} \\ \vdots \\ a_{\sigma(n-1)} + \end{bmatrix} + + And the permutation of matrix columns is defined as: + + .. math:: + B := \begin{bmatrix} + \alpha_{\sigma(0)} & \alpha_{\sigma(1)} & + \cdots & \alpha_{\sigma(n-1)} + \end{bmatrix} + """ + from sympy.combinatorics import Permutation + + # allow british variants and `columns` + if direction == 'forwards': + direction = 'forward' + if direction == 'backwards': + direction = 'backward' + if orientation == 'columns': + orientation = 'cols' + + if direction not in ('forward', 'backward'): + raise TypeError("direction='{}' is an invalid kwarg. " + "Try 'forward' or 'backward'".format(direction)) + if orientation not in ('rows', 'cols'): + raise TypeError("orientation='{}' is an invalid kwarg. " + "Try 'rows' or 'cols'".format(orientation)) + + if not isinstance(perm, (Permutation, Iterable)): + raise ValueError( + "{} must be a list, a list of lists, " + "or a SymPy permutation object.".format(perm)) + + # ensure all swaps are in range + max_index = self.rows if orientation == 'rows' else self.cols + if not all(0 <= t <= max_index for t in flatten(list(perm))): + raise IndexError("`swap` indices out of range.") + + if perm and not isinstance(perm, Permutation) and \ + isinstance(perm[0], Iterable): + if direction == 'forward': + perm = list(reversed(perm)) + perm = Permutation(perm, size=max_index+1) + else: + perm = Permutation(perm, size=max_index+1) + + if orientation == 'rows': + return self._eval_permute_rows(perm) + if orientation == 'cols': + return self._eval_permute_cols(perm) + + def permute_cols(self, swaps, direction='forward'): + """Alias for + ``self.permute(swaps, orientation='cols', direction=direction)`` + + See Also + ======== + + permute + """ + return self.permute(swaps, orientation='cols', direction=direction) + + def permute_rows(self, swaps, direction='forward'): + """Alias for + ``self.permute(swaps, orientation='rows', direction=direction)`` + + See Also + ======== + + permute + """ + return self.permute(swaps, orientation='rows', direction=direction) + + def refine(self, assumptions=True): + """Apply refine to each element of the matrix. + + Examples + ======== + + >>> from sympy import Symbol, Matrix, Abs, sqrt, Q + >>> x = Symbol('x') + >>> Matrix([[Abs(x)**2, sqrt(x**2)],[sqrt(x**2), Abs(x)**2]]) + Matrix([ + [ Abs(x)**2, sqrt(x**2)], + [sqrt(x**2), Abs(x)**2]]) + >>> _.refine(Q.real(x)) + Matrix([ + [ x**2, Abs(x)], + [Abs(x), x**2]]) + + """ + return self.applyfunc(lambda x: refine(x, assumptions)) + + def replace(self, F, G, map=False, simultaneous=True, exact=None): + """Replaces Function F in Matrix entries with Function G. + + Examples + ======== + + >>> from sympy import symbols, Function, Matrix + >>> F, G = symbols('F, G', cls=Function) + >>> M = Matrix(2, 2, lambda i, j: F(i+j)) ; M + Matrix([ + [F(0), F(1)], + [F(1), F(2)]]) + >>> N = M.replace(F,G) + >>> N + Matrix([ + [G(0), G(1)], + [G(1), G(2)]]) + """ + return self.applyfunc( + lambda x: x.replace(F, G, map=map, simultaneous=simultaneous, exact=exact)) + + def rot90(self, k=1): + """Rotates Matrix by 90 degrees + + Parameters + ========== + + k : int + Specifies how many times the matrix is rotated by 90 degrees + (clockwise when positive, counter-clockwise when negative). + + Examples + ======== + + >>> from sympy import Matrix, symbols + >>> A = Matrix(2, 2, symbols('a:d')) + >>> A + Matrix([ + [a, b], + [c, d]]) + + Rotating the matrix clockwise one time: + + >>> A.rot90(1) + Matrix([ + [c, a], + [d, b]]) + + Rotating the matrix anticlockwise two times: + + >>> A.rot90(-2) + Matrix([ + [d, c], + [b, a]]) + """ + + mod = k%4 + if mod == 0: + return self + if mod == 1: + return self[::-1, ::].T + if mod == 2: + return self[::-1, ::-1] + if mod == 3: + return self[::, ::-1].T + + def simplify(self, **kwargs): + """Apply simplify to each element of the matrix. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy import SparseMatrix, sin, cos + >>> SparseMatrix(1, 1, [x*sin(y)**2 + x*cos(y)**2]) + Matrix([[x*sin(y)**2 + x*cos(y)**2]]) + >>> _.simplify() + Matrix([[x]]) + """ + return self.applyfunc(lambda x: x.simplify(**kwargs)) + + def subs(self, *args, **kwargs): # should mirror core.basic.subs + """Return a new matrix with subs applied to each entry. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy import SparseMatrix, Matrix + >>> SparseMatrix(1, 1, [x]) + Matrix([[x]]) + >>> _.subs(x, y) + Matrix([[y]]) + >>> Matrix(_).subs(y, x) + Matrix([[x]]) + """ + + if len(args) == 1 and not isinstance(args[0], (dict, set)) and iter(args[0]) and not is_sequence(args[0]): + args = (list(args[0]),) + + return self.applyfunc(lambda x: x.subs(*args, **kwargs)) + + def trace(self): + """ + Returns the trace of a square matrix i.e. the sum of the + diagonal elements. + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix(2, 2, [1, 2, 3, 4]) + >>> A.trace() + 5 + + """ + if self.rows != self.cols: + raise NonSquareMatrixError() + return self._eval_trace() + + def transpose(self): + """ + Returns the transpose of the matrix. + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix(2, 2, [1, 2, 3, 4]) + >>> A.transpose() + Matrix([ + [1, 3], + [2, 4]]) + + >>> from sympy import Matrix, I + >>> m=Matrix(((1, 2+I), (3, 4))) + >>> m + Matrix([ + [1, 2 + I], + [3, 4]]) + >>> m.transpose() + Matrix([ + [ 1, 3], + [2 + I, 4]]) + >>> m.T == m.transpose() + True + + See Also + ======== + + conjugate: By-element conjugation + + """ + return self._eval_transpose() + + @property + def T(self): + '''Matrix transposition''' + return self.transpose() + + @property + def C(self): + '''By-element conjugation''' + return self.conjugate() + + def n(self, *args, **kwargs): + """Apply evalf() to each element of self.""" + return self.evalf(*args, **kwargs) + + def xreplace(self, rule): # should mirror core.basic.xreplace + """Return a new matrix with xreplace applied to each entry. + + Examples + ======== + + >>> from sympy.abc import x, y + >>> from sympy import SparseMatrix, Matrix + >>> SparseMatrix(1, 1, [x]) + Matrix([[x]]) + >>> _.xreplace({x: y}) + Matrix([[y]]) + >>> Matrix(_).xreplace({y: x}) + Matrix([[x]]) + """ + return self.applyfunc(lambda x: x.xreplace(rule)) + + def _eval_simplify(self, **kwargs): + # XXX: We can't use self.simplify here as mutable subclasses will + # override simplify and have it return None + return MatrixOperations.simplify(self, **kwargs) + + def _eval_trigsimp(self, **opts): + from sympy.simplify.trigsimp import trigsimp + return self.applyfunc(lambda x: trigsimp(x, **opts)) + + def upper_triangular(self, k=0): + """Return the elements on and above the kth diagonal of a matrix. + If k is not specified then simply returns upper-triangular portion + of a matrix + + Examples + ======== + + >>> from sympy import ones + >>> A = ones(4) + >>> A.upper_triangular() + Matrix([ + [1, 1, 1, 1], + [0, 1, 1, 1], + [0, 0, 1, 1], + [0, 0, 0, 1]]) + + >>> A.upper_triangular(2) + Matrix([ + [0, 0, 1, 1], + [0, 0, 0, 1], + [0, 0, 0, 0], + [0, 0, 0, 0]]) + + >>> A.upper_triangular(-1) + Matrix([ + [1, 1, 1, 1], + [1, 1, 1, 1], + [0, 1, 1, 1], + [0, 0, 1, 1]]) + + """ + + def entry(i, j): + return self[i, j] if i + k <= j else self.zero + + return self._new(self.rows, self.cols, entry) + + + def lower_triangular(self, k=0): + """Return the elements on and below the kth diagonal of a matrix. + If k is not specified then simply returns lower-triangular portion + of a matrix + + Examples + ======== + + >>> from sympy import ones + >>> A = ones(4) + >>> A.lower_triangular() + Matrix([ + [1, 0, 0, 0], + [1, 1, 0, 0], + [1, 1, 1, 0], + [1, 1, 1, 1]]) + + >>> A.lower_triangular(-2) + Matrix([ + [0, 0, 0, 0], + [0, 0, 0, 0], + [1, 0, 0, 0], + [1, 1, 0, 0]]) + + >>> A.lower_triangular(1) + Matrix([ + [1, 1, 0, 0], + [1, 1, 1, 0], + [1, 1, 1, 1], + [1, 1, 1, 1]]) + + """ + + def entry(i, j): + return self[i, j] if i + k >= j else self.zero + + return self._new(self.rows, self.cols, entry) + + + +class MatrixArithmetic(MatrixRequired): + """Provides basic matrix arithmetic operations. + Should not be instantiated directly.""" + + _op_priority = 10.01 + + def _eval_Abs(self): + return self._new(self.rows, self.cols, lambda i, j: Abs(self[i, j])) + + def _eval_add(self, other): + return self._new(self.rows, self.cols, + lambda i, j: self[i, j] + other[i, j]) + + def _eval_matrix_mul(self, other): + def entry(i, j): + vec = [self[i,k]*other[k,j] for k in range(self.cols)] + try: + return Add(*vec) + except (TypeError, SympifyError): + # Some matrices don't work with `sum` or `Add` + # They don't work with `sum` because `sum` tries to add `0` + # Fall back to a safe way to multiply if the `Add` fails. + return reduce(lambda a, b: a + b, vec) + + return self._new(self.rows, other.cols, entry) + + def _eval_matrix_mul_elementwise(self, other): + return self._new(self.rows, self.cols, lambda i, j: self[i,j]*other[i,j]) + + def _eval_matrix_rmul(self, other): + def entry(i, j): + return sum(other[i,k]*self[k,j] for k in range(other.cols)) + return self._new(other.rows, self.cols, entry) + + def _eval_pow_by_recursion(self, num): + if num == 1: + return self + + if num % 2 == 1: + a, b = self, self._eval_pow_by_recursion(num - 1) + else: + a = b = self._eval_pow_by_recursion(num // 2) + + return a.multiply(b) + + def _eval_pow_by_cayley(self, exp): + from sympy.discrete.recurrences import linrec_coeffs + row = self.shape[0] + p = self.charpoly() + + coeffs = (-p).all_coeffs()[1:] + coeffs = linrec_coeffs(coeffs, exp) + new_mat = self.eye(row) + ans = self.zeros(row) + + for i in range(row): + ans += coeffs[i]*new_mat + new_mat *= self + + return ans + + def _eval_pow_by_recursion_dotprodsimp(self, num, prevsimp=None): + if prevsimp is None: + prevsimp = [True]*len(self) + + if num == 1: + return self + + if num % 2 == 1: + a, b = self, self._eval_pow_by_recursion_dotprodsimp(num - 1, + prevsimp=prevsimp) + else: + a = b = self._eval_pow_by_recursion_dotprodsimp(num // 2, + prevsimp=prevsimp) + + m = a.multiply(b, dotprodsimp=False) + lenm = len(m) + elems = [None]*lenm + + for i in range(lenm): + if prevsimp[i]: + elems[i], prevsimp[i] = _dotprodsimp(m[i], withsimp=True) + else: + elems[i] = m[i] + + return m._new(m.rows, m.cols, elems) + + def _eval_scalar_mul(self, other): + return self._new(self.rows, self.cols, lambda i, j: self[i,j]*other) + + def _eval_scalar_rmul(self, other): + return self._new(self.rows, self.cols, lambda i, j: other*self[i,j]) + + def _eval_Mod(self, other): + return self._new(self.rows, self.cols, lambda i, j: Mod(self[i, j], other)) + + # Python arithmetic functions + def __abs__(self): + """Returns a new matrix with entry-wise absolute values.""" + return self._eval_Abs() + + @call_highest_priority('__radd__') + def __add__(self, other): + """Return self + other, raising ShapeError if shapes do not match.""" + if isinstance(other, NDimArray): # Matrix and array addition is currently not implemented + return NotImplemented + other = _matrixify(other) + # matrix-like objects can have shapes. This is + # our first sanity check. + if hasattr(other, 'shape'): + if self.shape != other.shape: + raise ShapeError("Matrix size mismatch: %s + %s" % ( + self.shape, other.shape)) + + # honest SymPy matrices defer to their class's routine + if getattr(other, 'is_Matrix', False): + # call the highest-priority class's _eval_add + a, b = self, other + if a.__class__ != classof(a, b): + b, a = a, b + return a._eval_add(b) + # Matrix-like objects can be passed to CommonMatrix routines directly. + if getattr(other, 'is_MatrixLike', False): + return MatrixArithmetic._eval_add(self, other) + + raise TypeError('cannot add %s and %s' % (type(self), type(other))) + + @call_highest_priority('__rtruediv__') + def __truediv__(self, other): + return self * (self.one / other) + + @call_highest_priority('__rmatmul__') + def __matmul__(self, other): + other = _matrixify(other) + if not getattr(other, 'is_Matrix', False) and not getattr(other, 'is_MatrixLike', False): + return NotImplemented + + return self.__mul__(other) + + def __mod__(self, other): + return self.applyfunc(lambda x: x % other) + + @call_highest_priority('__rmul__') + def __mul__(self, other): + """Return self*other where other is either a scalar or a matrix + of compatible dimensions. + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix([[1, 2, 3], [4, 5, 6]]) + >>> 2*A == A*2 == Matrix([[2, 4, 6], [8, 10, 12]]) + True + >>> B = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) + >>> A*B + Matrix([ + [30, 36, 42], + [66, 81, 96]]) + >>> B*A + Traceback (most recent call last): + ... + ShapeError: Matrices size mismatch. + >>> + + See Also + ======== + + matrix_multiply_elementwise + """ + + return self.multiply(other) + + def multiply(self, other, dotprodsimp=None): + """Same as __mul__() but with optional simplification. + + Parameters + ========== + + dotprodsimp : bool, optional + Specifies whether intermediate term algebraic simplification is used + during matrix multiplications to control expression blowup and thus + speed up calculation. Default is off. + """ + + isimpbool = _get_intermediate_simp_bool(False, dotprodsimp) + other = _matrixify(other) + # matrix-like objects can have shapes. This is + # our first sanity check. Double check other is not explicitly not a Matrix. + if (hasattr(other, 'shape') and len(other.shape) == 2 and + (getattr(other, 'is_Matrix', True) or + getattr(other, 'is_MatrixLike', True))): + if self.shape[1] != other.shape[0]: + raise ShapeError("Matrix size mismatch: %s * %s." % ( + self.shape, other.shape)) + + # honest SymPy matrices defer to their class's routine + if getattr(other, 'is_Matrix', False): + m = self._eval_matrix_mul(other) + if isimpbool: + return m._new(m.rows, m.cols, [_dotprodsimp(e) for e in m]) + return m + + # Matrix-like objects can be passed to CommonMatrix routines directly. + if getattr(other, 'is_MatrixLike', False): + return MatrixArithmetic._eval_matrix_mul(self, other) + + # if 'other' is not iterable then scalar multiplication. + if not isinstance(other, Iterable): + try: + return self._eval_scalar_mul(other) + except TypeError: + pass + + return NotImplemented + + def multiply_elementwise(self, other): + """Return the Hadamard product (elementwise product) of A and B + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix([[0, 1, 2], [3, 4, 5]]) + >>> B = Matrix([[1, 10, 100], [100, 10, 1]]) + >>> A.multiply_elementwise(B) + Matrix([ + [ 0, 10, 200], + [300, 40, 5]]) + + See Also + ======== + + sympy.matrices.matrixbase.MatrixBase.cross + sympy.matrices.matrixbase.MatrixBase.dot + multiply + """ + if self.shape != other.shape: + raise ShapeError("Matrix shapes must agree {} != {}".format(self.shape, other.shape)) + + return self._eval_matrix_mul_elementwise(other) + + def __neg__(self): + return self._eval_scalar_mul(-1) + + @call_highest_priority('__rpow__') + def __pow__(self, exp): + """Return self**exp a scalar or symbol.""" + + return self.pow(exp) + + + def pow(self, exp, method=None): + r"""Return self**exp a scalar or symbol. + + Parameters + ========== + + method : multiply, mulsimp, jordan, cayley + If multiply then it returns exponentiation using recursion. + If jordan then Jordan form exponentiation will be used. + If cayley then the exponentiation is done using Cayley-Hamilton + theorem. + If mulsimp then the exponentiation is done using recursion + with dotprodsimp. This specifies whether intermediate term + algebraic simplification is used during naive matrix power to + control expression blowup and thus speed up calculation. + If None, then it heuristically decides which method to use. + + """ + + if method is not None and method not in ['multiply', 'mulsimp', 'jordan', 'cayley']: + raise TypeError('No such method') + if self.rows != self.cols: + raise NonSquareMatrixError() + a = self + jordan_pow = getattr(a, '_matrix_pow_by_jordan_blocks', None) + exp = sympify(exp) + + if exp.is_zero: + return a._new(a.rows, a.cols, lambda i, j: int(i == j)) + if exp == 1: + return a + + diagonal = getattr(a, 'is_diagonal', None) + if diagonal is not None and diagonal(): + return a._new(a.rows, a.cols, lambda i, j: a[i,j]**exp if i == j else 0) + + if exp.is_Number and exp % 1 == 0: + if a.rows == 1: + return a._new([[a[0]**exp]]) + if exp < 0: + exp = -exp + a = a.inv() + # When certain conditions are met, + # Jordan block algorithm is faster than + # computation by recursion. + if method == 'jordan': + try: + return jordan_pow(exp) + except MatrixError: + if method == 'jordan': + raise + + elif method == 'cayley': + if not exp.is_Number or exp % 1 != 0: + raise ValueError("cayley method is only valid for integer powers") + return a._eval_pow_by_cayley(exp) + + elif method == "mulsimp": + if not exp.is_Number or exp % 1 != 0: + raise ValueError("mulsimp method is only valid for integer powers") + return a._eval_pow_by_recursion_dotprodsimp(exp) + + elif method == "multiply": + if not exp.is_Number or exp % 1 != 0: + raise ValueError("multiply method is only valid for integer powers") + return a._eval_pow_by_recursion(exp) + + elif method is None and exp.is_Number and exp % 1 == 0: + if exp.is_Float: + exp = Integer(exp) + # Decide heuristically which method to apply + if a.rows == 2 and exp > 100000: + return jordan_pow(exp) + elif _get_intermediate_simp_bool(True, None): + return a._eval_pow_by_recursion_dotprodsimp(exp) + elif exp > 10000: + return a._eval_pow_by_cayley(exp) + else: + return a._eval_pow_by_recursion(exp) + + if jordan_pow: + try: + return jordan_pow(exp) + except NonInvertibleMatrixError: + # Raised by jordan_pow on zero determinant matrix unless exp is + # definitely known to be a non-negative integer. + # Here we raise if n is definitely not a non-negative integer + # but otherwise we can leave this as an unevaluated MatPow. + if exp.is_integer is False or exp.is_nonnegative is False: + raise + + from sympy.matrices.expressions import MatPow + return MatPow(a, exp) + + @call_highest_priority('__add__') + def __radd__(self, other): + return self + other + + @call_highest_priority('__matmul__') + def __rmatmul__(self, other): + other = _matrixify(other) + if not getattr(other, 'is_Matrix', False) and not getattr(other, 'is_MatrixLike', False): + return NotImplemented + + return self.__rmul__(other) + + @call_highest_priority('__mul__') + def __rmul__(self, other): + return self.rmultiply(other) + + def rmultiply(self, other, dotprodsimp=None): + """Same as __rmul__() but with optional simplification. + + Parameters + ========== + + dotprodsimp : bool, optional + Specifies whether intermediate term algebraic simplification is used + during matrix multiplications to control expression blowup and thus + speed up calculation. Default is off. + """ + isimpbool = _get_intermediate_simp_bool(False, dotprodsimp) + other = _matrixify(other) + # matrix-like objects can have shapes. This is + # our first sanity check. Double check other is not explicitly not a Matrix. + if (hasattr(other, 'shape') and len(other.shape) == 2 and + (getattr(other, 'is_Matrix', True) or + getattr(other, 'is_MatrixLike', True))): + if self.shape[0] != other.shape[1]: + raise ShapeError("Matrix size mismatch.") + + # honest SymPy matrices defer to their class's routine + if getattr(other, 'is_Matrix', False): + m = self._eval_matrix_rmul(other) + if isimpbool: + return m._new(m.rows, m.cols, [_dotprodsimp(e) for e in m]) + return m + # Matrix-like objects can be passed to CommonMatrix routines directly. + if getattr(other, 'is_MatrixLike', False): + return MatrixArithmetic._eval_matrix_rmul(self, other) + + # if 'other' is not iterable then scalar multiplication. + if not isinstance(other, Iterable): + try: + return self._eval_scalar_rmul(other) + except TypeError: + pass + + return NotImplemented + + @call_highest_priority('__sub__') + def __rsub__(self, a): + return (-self) + a + + @call_highest_priority('__rsub__') + def __sub__(self, a): + return self + (-a) + + +class MatrixCommon(MatrixArithmetic, MatrixOperations, MatrixProperties, + MatrixSpecial, MatrixShaping): + """All common matrix operations including basic arithmetic, shaping, + and special matrices like `zeros`, and `eye`.""" + _diff_wrt: bool = True + + +class _MinimalMatrix: + """Class providing the minimum functionality + for a matrix-like object and implementing every method + required for a `MatrixRequired`. This class does not have everything + needed to become a full-fledged SymPy object, but it will satisfy the + requirements of anything inheriting from `MatrixRequired`. If you wish + to make a specialized matrix type, make sure to implement these + methods and properties with the exception of `__init__` and `__repr__` + which are included for convenience.""" + + is_MatrixLike = True + _sympify = staticmethod(sympify) + _class_priority = 3 + zero = S.Zero + one = S.One + + is_Matrix = True + is_MatrixExpr = False + + @classmethod + def _new(cls, *args, **kwargs): + return cls(*args, **kwargs) + + def __init__(self, rows, cols=None, mat=None, copy=False): + if isfunction(mat): + # if we passed in a function, use that to populate the indices + mat = [mat(i, j) for i in range(rows) for j in range(cols)] + if cols is None and mat is None: + mat = rows + rows, cols = getattr(mat, 'shape', (rows, cols)) + try: + # if we passed in a list of lists, flatten it and set the size + if cols is None and mat is None: + mat = rows + cols = len(mat[0]) + rows = len(mat) + mat = [x for l in mat for x in l] + except (IndexError, TypeError): + pass + self.mat = tuple(self._sympify(x) for x in mat) + self.rows, self.cols = rows, cols + if self.rows is None or self.cols is None: + raise NotImplementedError("Cannot initialize matrix with given parameters") + + def __getitem__(self, key): + def _normalize_slices(row_slice, col_slice): + """Ensure that row_slice and col_slice do not have + `None` in their arguments. Any integers are converted + to slices of length 1""" + if not isinstance(row_slice, slice): + row_slice = slice(row_slice, row_slice + 1, None) + row_slice = slice(*row_slice.indices(self.rows)) + + if not isinstance(col_slice, slice): + col_slice = slice(col_slice, col_slice + 1, None) + col_slice = slice(*col_slice.indices(self.cols)) + + return (row_slice, col_slice) + + def _coord_to_index(i, j): + """Return the index in _mat corresponding + to the (i,j) position in the matrix. """ + return i * self.cols + j + + if isinstance(key, tuple): + i, j = key + if isinstance(i, slice) or isinstance(j, slice): + # if the coordinates are not slices, make them so + # and expand the slices so they don't contain `None` + i, j = _normalize_slices(i, j) + + rowsList, colsList = list(range(self.rows))[i], \ + list(range(self.cols))[j] + indices = (i * self.cols + j for i in rowsList for j in + colsList) + return self._new(len(rowsList), len(colsList), + [self.mat[i] for i in indices]) + + # if the key is a tuple of ints, change + # it to an array index + key = _coord_to_index(i, j) + return self.mat[key] + + def __eq__(self, other): + try: + classof(self, other) + except TypeError: + return False + return ( + self.shape == other.shape and list(self) == list(other)) + + def __len__(self): + return self.rows*self.cols + + def __repr__(self): + return "_MinimalMatrix({}, {}, {})".format(self.rows, self.cols, + self.mat) + + @property + def shape(self): + return (self.rows, self.cols) + + +class _CastableMatrix: # this is needed here ONLY FOR TESTS. + def as_mutable(self): + return self + + def as_immutable(self): + return self + + +class _MatrixWrapper: + """Wrapper class providing the minimum functionality for a matrix-like + object: .rows, .cols, .shape, indexability, and iterability. CommonMatrix + math operations should work on matrix-like objects. This one is intended for + matrix-like objects which use the same indexing format as SymPy with respect + to returning matrix elements instead of rows for non-tuple indexes. + """ + + is_Matrix = False # needs to be here because of __getattr__ + is_MatrixLike = True + + def __init__(self, mat, shape): + self.mat = mat + self.shape = shape + self.rows, self.cols = shape + + def __getitem__(self, key): + if isinstance(key, tuple): + return sympify(self.mat.__getitem__(key)) + + return sympify(self.mat.__getitem__((key // self.rows, key % self.cols))) + + def __iter__(self): # supports numpy.matrix and numpy.array + mat = self.mat + cols = self.cols + + return iter(sympify(mat[r, c]) for r in range(self.rows) for c in range(cols)) + + +def _matrixify(mat): + """If `mat` is a Matrix or is matrix-like, + return a Matrix or MatrixWrapper object. Otherwise + `mat` is passed through without modification.""" + + if getattr(mat, 'is_Matrix', False) or getattr(mat, 'is_MatrixLike', False): + return mat + + if not(getattr(mat, 'is_Matrix', True) or getattr(mat, 'is_MatrixLike', True)): + return mat + + shape = None + + if hasattr(mat, 'shape'): # numpy, scipy.sparse + if len(mat.shape) == 2: + shape = mat.shape + elif hasattr(mat, 'rows') and hasattr(mat, 'cols'): # mpmath + shape = (mat.rows, mat.cols) + + if shape: + return _MatrixWrapper(mat, shape) + + return mat + + +def a2idx(j, n=None): + """Return integer after making positive and validating against n.""" + if not isinstance(j, int): + jindex = getattr(j, '__index__', None) + if jindex is not None: + j = jindex() + else: + raise IndexError("Invalid index a[%r]" % (j,)) + if n is not None: + if j < 0: + j += n + if not (j >= 0 and j < n): + raise IndexError("Index out of range: a[%s]" % (j,)) + return int(j) + + +def classof(A, B): + """ + Get the type of the result when combining matrices of different types. + + Currently the strategy is that immutability is contagious. + + Examples + ======== + + >>> from sympy import Matrix, ImmutableMatrix + >>> from sympy.matrices.matrixbase import classof + >>> M = Matrix([[1, 2], [3, 4]]) # a Mutable Matrix + >>> IM = ImmutableMatrix([[1, 2], [3, 4]]) + >>> classof(M, IM) + + """ + priority_A = getattr(A, '_class_priority', None) + priority_B = getattr(B, '_class_priority', None) + if None not in (priority_A, priority_B): + if A._class_priority > B._class_priority: + return A.__class__ + else: + return B.__class__ + + try: + import numpy + except ImportError: + pass + else: + if isinstance(A, numpy.ndarray): + return B.__class__ + if isinstance(B, numpy.ndarray): + return A.__class__ + + raise TypeError("Incompatible classes %s, %s" % (A.__class__, B.__class__)) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/decompositions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/decompositions.py new file mode 100644 index 0000000000000000000000000000000000000000..a8dd466d84c957b870396a050fd25ec21e7113a3 --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/decompositions.py @@ -0,0 +1,1621 @@ +import copy + +from sympy.core import S +from sympy.core.function import expand_mul +from sympy.functions.elementary.miscellaneous import Min, sqrt +from sympy.functions.elementary.complexes import sign + +from .exceptions import NonSquareMatrixError, NonPositiveDefiniteMatrixError +from .utilities import _get_intermediate_simp, _iszero +from .determinant import _find_reasonable_pivot_naive + + +def _rank_decomposition(M, iszerofunc=_iszero, simplify=False): + r"""Returns a pair of matrices (`C`, `F`) with matching rank + such that `A = C F`. + + Parameters + ========== + + iszerofunc : Function, optional + A function used for detecting whether an element can + act as a pivot. ``lambda x: x.is_zero`` is used by default. + + simplify : Bool or Function, optional + A function used to simplify elements when looking for a + pivot. By default SymPy's ``simplify`` is used. + + Returns + ======= + + (C, F) : Matrices + `C` and `F` are full-rank matrices with rank as same as `A`, + whose product gives `A`. + + See Notes for additional mathematical details. + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix([ + ... [1, 3, 1, 4], + ... [2, 7, 3, 9], + ... [1, 5, 3, 1], + ... [1, 2, 0, 8] + ... ]) + >>> C, F = A.rank_decomposition() + >>> C + Matrix([ + [1, 3, 4], + [2, 7, 9], + [1, 5, 1], + [1, 2, 8]]) + >>> F + Matrix([ + [1, 0, -2, 0], + [0, 1, 1, 0], + [0, 0, 0, 1]]) + >>> C * F == A + True + + Notes + ===== + + Obtaining `F`, an RREF of `A`, is equivalent to creating a + product + + .. math:: + E_n E_{n-1} ... E_1 A = F + + where `E_n, E_{n-1}, \dots, E_1` are the elimination matrices or + permutation matrices equivalent to each row-reduction step. + + The inverse of the same product of elimination matrices gives + `C`: + + .. math:: + C = \left(E_n E_{n-1} \dots E_1\right)^{-1} + + It is not necessary, however, to actually compute the inverse: + the columns of `C` are those from the original matrix with the + same column indices as the indices of the pivot columns of `F`. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Rank_factorization + + .. [2] Piziak, R.; Odell, P. L. (1 June 1999). + "Full Rank Factorization of Matrices". + Mathematics Magazine. 72 (3): 193. doi:10.2307/2690882 + + See Also + ======== + + sympy.matrices.matrixbase.MatrixBase.rref + """ + + F, pivot_cols = M.rref(simplify=simplify, iszerofunc=iszerofunc, + pivots=True) + rank = len(pivot_cols) + + C = M.extract(range(M.rows), pivot_cols) + F = F[:rank, :] + + return C, F + + +def _liupc(M): + """Liu's algorithm, for pre-determination of the Elimination Tree of + the given matrix, used in row-based symbolic Cholesky factorization. + + Examples + ======== + + >>> from sympy import SparseMatrix + >>> S = SparseMatrix([ + ... [1, 0, 3, 2], + ... [0, 0, 1, 0], + ... [4, 0, 0, 5], + ... [0, 6, 7, 0]]) + >>> S.liupc() + ([[0], [], [0], [1, 2]], [4, 3, 4, 4]) + + References + ========== + + .. [1] Symbolic Sparse Cholesky Factorization using Elimination Trees, + Jeroen Van Grondelle (1999) + https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.39.7582 + """ + # Algorithm 2.4, p 17 of reference + + # get the indices of the elements that are non-zero on or below diag + R = [[] for r in range(M.rows)] + + for r, c, _ in M.row_list(): + if c <= r: + R[r].append(c) + + inf = len(R) # nothing will be this large + parent = [inf]*M.rows + virtual = [inf]*M.rows + + for r in range(M.rows): + for c in R[r][:-1]: + while virtual[c] < r: + t = virtual[c] + virtual[c] = r + c = t + + if virtual[c] == inf: + parent[c] = virtual[c] = r + + return R, parent + +def _row_structure_symbolic_cholesky(M): + """Symbolic cholesky factorization, for pre-determination of the + non-zero structure of the Cholesky factororization. + + Examples + ======== + + >>> from sympy import SparseMatrix + >>> S = SparseMatrix([ + ... [1, 0, 3, 2], + ... [0, 0, 1, 0], + ... [4, 0, 0, 5], + ... [0, 6, 7, 0]]) + >>> S.row_structure_symbolic_cholesky() + [[0], [], [0], [1, 2]] + + References + ========== + + .. [1] Symbolic Sparse Cholesky Factorization using Elimination Trees, + Jeroen Van Grondelle (1999) + https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.39.7582 + """ + + R, parent = M.liupc() + inf = len(R) # this acts as infinity + Lrow = copy.deepcopy(R) + + for k in range(M.rows): + for j in R[k]: + while j != inf and j != k: + Lrow[k].append(j) + j = parent[j] + + Lrow[k] = sorted(set(Lrow[k])) + + return Lrow + + +def _cholesky(M, hermitian=True): + """Returns the Cholesky-type decomposition L of a matrix A + such that L * L.H == A if hermitian flag is True, + or L * L.T == A if hermitian is False. + + A must be a Hermitian positive-definite matrix if hermitian is True, + or a symmetric matrix if it is False. + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix(((25, 15, -5), (15, 18, 0), (-5, 0, 11))) + >>> A.cholesky() + Matrix([ + [ 5, 0, 0], + [ 3, 3, 0], + [-1, 1, 3]]) + >>> A.cholesky() * A.cholesky().T + Matrix([ + [25, 15, -5], + [15, 18, 0], + [-5, 0, 11]]) + + The matrix can have complex entries: + + >>> from sympy import I + >>> A = Matrix(((9, 3*I), (-3*I, 5))) + >>> A.cholesky() + Matrix([ + [ 3, 0], + [-I, 2]]) + >>> A.cholesky() * A.cholesky().H + Matrix([ + [ 9, 3*I], + [-3*I, 5]]) + + Non-hermitian Cholesky-type decomposition may be useful when the + matrix is not positive-definite. + + >>> A = Matrix([[1, 2], [2, 1]]) + >>> L = A.cholesky(hermitian=False) + >>> L + Matrix([ + [1, 0], + [2, sqrt(3)*I]]) + >>> L*L.T == A + True + + See Also + ======== + + sympy.matrices.dense.DenseMatrix.LDLdecomposition + sympy.matrices.matrixbase.MatrixBase.LUdecomposition + QRdecomposition + """ + + from .dense import MutableDenseMatrix + + if not M.is_square: + raise NonSquareMatrixError("Matrix must be square.") + if hermitian and not M.is_hermitian: + raise ValueError("Matrix must be Hermitian.") + if not hermitian and not M.is_symmetric(): + raise ValueError("Matrix must be symmetric.") + + L = MutableDenseMatrix.zeros(M.rows, M.rows) + + if hermitian: + for i in range(M.rows): + for j in range(i): + L[i, j] = ((1 / L[j, j])*(M[i, j] - + sum(L[i, k]*L[j, k].conjugate() for k in range(j)))) + + Lii2 = (M[i, i] - + sum(L[i, k]*L[i, k].conjugate() for k in range(i))) + + if Lii2.is_positive is False: + raise NonPositiveDefiniteMatrixError( + "Matrix must be positive-definite") + + L[i, i] = sqrt(Lii2) + + else: + for i in range(M.rows): + for j in range(i): + L[i, j] = ((1 / L[j, j])*(M[i, j] - + sum(L[i, k]*L[j, k] for k in range(j)))) + + L[i, i] = sqrt(M[i, i] - + sum(L[i, k]**2 for k in range(i))) + + return M._new(L) + +def _cholesky_sparse(M, hermitian=True): + """ + Returns the Cholesky decomposition L of a matrix A + such that L * L.T = A + + A must be a square, symmetric, positive-definite + and non-singular matrix + + Examples + ======== + + >>> from sympy import SparseMatrix + >>> A = SparseMatrix(((25,15,-5),(15,18,0),(-5,0,11))) + >>> A.cholesky() + Matrix([ + [ 5, 0, 0], + [ 3, 3, 0], + [-1, 1, 3]]) + >>> A.cholesky() * A.cholesky().T == A + True + + The matrix can have complex entries: + + >>> from sympy import I + >>> A = SparseMatrix(((9, 3*I), (-3*I, 5))) + >>> A.cholesky() + Matrix([ + [ 3, 0], + [-I, 2]]) + >>> A.cholesky() * A.cholesky().H + Matrix([ + [ 9, 3*I], + [-3*I, 5]]) + + Non-hermitian Cholesky-type decomposition may be useful when the + matrix is not positive-definite. + + >>> A = SparseMatrix([[1, 2], [2, 1]]) + >>> L = A.cholesky(hermitian=False) + >>> L + Matrix([ + [1, 0], + [2, sqrt(3)*I]]) + >>> L*L.T == A + True + + See Also + ======== + + sympy.matrices.sparse.SparseMatrix.LDLdecomposition + sympy.matrices.matrixbase.MatrixBase.LUdecomposition + QRdecomposition + """ + + from .dense import MutableDenseMatrix + + if not M.is_square: + raise NonSquareMatrixError("Matrix must be square.") + if hermitian and not M.is_hermitian: + raise ValueError("Matrix must be Hermitian.") + if not hermitian and not M.is_symmetric(): + raise ValueError("Matrix must be symmetric.") + + dps = _get_intermediate_simp(expand_mul, expand_mul) + Crowstruc = M.row_structure_symbolic_cholesky() + C = MutableDenseMatrix.zeros(M.rows) + + for i in range(len(Crowstruc)): + for j in Crowstruc[i]: + if i != j: + C[i, j] = M[i, j] + summ = 0 + + for p1 in Crowstruc[i]: + if p1 < j: + for p2 in Crowstruc[j]: + if p2 < j: + if p1 == p2: + if hermitian: + summ += C[i, p1]*C[j, p1].conjugate() + else: + summ += C[i, p1]*C[j, p1] + else: + break + else: + break + + C[i, j] = dps((C[i, j] - summ) / C[j, j]) + + else: # i == j + C[j, j] = M[j, j] + summ = 0 + + for k in Crowstruc[j]: + if k < j: + if hermitian: + summ += C[j, k]*C[j, k].conjugate() + else: + summ += C[j, k]**2 + else: + break + + Cjj2 = dps(C[j, j] - summ) + + if hermitian and Cjj2.is_positive is False: + raise NonPositiveDefiniteMatrixError( + "Matrix must be positive-definite") + + C[j, j] = sqrt(Cjj2) + + return M._new(C) + + +def _LDLdecomposition(M, hermitian=True): + """Returns the LDL Decomposition (L, D) of matrix A, + such that L * D * L.H == A if hermitian flag is True, or + L * D * L.T == A if hermitian is False. + This method eliminates the use of square root. + Further this ensures that all the diagonal entries of L are 1. + A must be a Hermitian positive-definite matrix if hermitian is True, + or a symmetric matrix otherwise. + + Examples + ======== + + >>> from sympy import Matrix, eye + >>> A = Matrix(((25, 15, -5), (15, 18, 0), (-5, 0, 11))) + >>> L, D = A.LDLdecomposition() + >>> L + Matrix([ + [ 1, 0, 0], + [ 3/5, 1, 0], + [-1/5, 1/3, 1]]) + >>> D + Matrix([ + [25, 0, 0], + [ 0, 9, 0], + [ 0, 0, 9]]) + >>> L * D * L.T * A.inv() == eye(A.rows) + True + + The matrix can have complex entries: + + >>> from sympy import I + >>> A = Matrix(((9, 3*I), (-3*I, 5))) + >>> L, D = A.LDLdecomposition() + >>> L + Matrix([ + [ 1, 0], + [-I/3, 1]]) + >>> D + Matrix([ + [9, 0], + [0, 4]]) + >>> L*D*L.H == A + True + + See Also + ======== + + sympy.matrices.dense.DenseMatrix.cholesky + sympy.matrices.matrixbase.MatrixBase.LUdecomposition + QRdecomposition + """ + + from .dense import MutableDenseMatrix + + if not M.is_square: + raise NonSquareMatrixError("Matrix must be square.") + if hermitian and not M.is_hermitian: + raise ValueError("Matrix must be Hermitian.") + if not hermitian and not M.is_symmetric(): + raise ValueError("Matrix must be symmetric.") + + D = MutableDenseMatrix.zeros(M.rows, M.rows) + L = MutableDenseMatrix.eye(M.rows) + + if hermitian: + for i in range(M.rows): + for j in range(i): + L[i, j] = (1 / D[j, j])*(M[i, j] - sum( + L[i, k]*L[j, k].conjugate()*D[k, k] for k in range(j))) + + D[i, i] = (M[i, i] - + sum(L[i, k]*L[i, k].conjugate()*D[k, k] for k in range(i))) + + if D[i, i].is_positive is False: + raise NonPositiveDefiniteMatrixError( + "Matrix must be positive-definite") + + else: + for i in range(M.rows): + for j in range(i): + L[i, j] = (1 / D[j, j])*(M[i, j] - sum( + L[i, k]*L[j, k]*D[k, k] for k in range(j))) + + D[i, i] = M[i, i] - sum(L[i, k]**2*D[k, k] for k in range(i)) + + return M._new(L), M._new(D) + +def _LDLdecomposition_sparse(M, hermitian=True): + """ + Returns the LDL Decomposition (matrices ``L`` and ``D``) of matrix + ``A``, such that ``L * D * L.T == A``. ``A`` must be a square, + symmetric, positive-definite and non-singular. + + This method eliminates the use of square root and ensures that all + the diagonal entries of L are 1. + + Examples + ======== + + >>> from sympy import SparseMatrix + >>> A = SparseMatrix(((25, 15, -5), (15, 18, 0), (-5, 0, 11))) + >>> L, D = A.LDLdecomposition() + >>> L + Matrix([ + [ 1, 0, 0], + [ 3/5, 1, 0], + [-1/5, 1/3, 1]]) + >>> D + Matrix([ + [25, 0, 0], + [ 0, 9, 0], + [ 0, 0, 9]]) + >>> L * D * L.T == A + True + + """ + + from .dense import MutableDenseMatrix + + if not M.is_square: + raise NonSquareMatrixError("Matrix must be square.") + if hermitian and not M.is_hermitian: + raise ValueError("Matrix must be Hermitian.") + if not hermitian and not M.is_symmetric(): + raise ValueError("Matrix must be symmetric.") + + dps = _get_intermediate_simp(expand_mul, expand_mul) + Lrowstruc = M.row_structure_symbolic_cholesky() + L = MutableDenseMatrix.eye(M.rows) + D = MutableDenseMatrix.zeros(M.rows, M.cols) + + for i in range(len(Lrowstruc)): + for j in Lrowstruc[i]: + if i != j: + L[i, j] = M[i, j] + summ = 0 + + for p1 in Lrowstruc[i]: + if p1 < j: + for p2 in Lrowstruc[j]: + if p2 < j: + if p1 == p2: + if hermitian: + summ += L[i, p1]*L[j, p1].conjugate()*D[p1, p1] + else: + summ += L[i, p1]*L[j, p1]*D[p1, p1] + else: + break + else: + break + + L[i, j] = dps((L[i, j] - summ) / D[j, j]) + + else: # i == j + D[i, i] = M[i, i] + summ = 0 + + for k in Lrowstruc[i]: + if k < i: + if hermitian: + summ += L[i, k]*L[i, k].conjugate()*D[k, k] + else: + summ += L[i, k]**2*D[k, k] + else: + break + + D[i, i] = dps(D[i, i] - summ) + + if hermitian and D[i, i].is_positive is False: + raise NonPositiveDefiniteMatrixError( + "Matrix must be positive-definite") + + return M._new(L), M._new(D) + + +def _LUdecomposition(M, iszerofunc=_iszero, simpfunc=None, rankcheck=False): + """Returns (L, U, perm) where L is a lower triangular matrix with unit + diagonal, U is an upper triangular matrix, and perm is a list of row + swap index pairs. If A is the original matrix, then + ``A = (L*U).permuteBkwd(perm)``, and the row permutation matrix P such + that $P A = L U$ can be computed by ``P = eye(A.rows).permuteFwd(perm)``. + + See documentation for LUCombined for details about the keyword argument + rankcheck, iszerofunc, and simpfunc. + + Parameters + ========== + + rankcheck : bool, optional + Determines if this function should detect the rank + deficiency of the matrixis and should raise a + ``ValueError``. + + iszerofunc : function, optional + A function which determines if a given expression is zero. + + The function should be a callable that takes a single + SymPy expression and returns a 3-valued boolean value + ``True``, ``False``, or ``None``. + + It is internally used by the pivot searching algorithm. + See the notes section for a more information about the + pivot searching algorithm. + + simpfunc : function or None, optional + A function that simplifies the input. + + If this is specified as a function, this function should be + a callable that takes a single SymPy expression and returns + an another SymPy expression that is algebraically + equivalent. + + If ``None``, it indicates that the pivot search algorithm + should not attempt to simplify any candidate pivots. + + It is internally used by the pivot searching algorithm. + See the notes section for a more information about the + pivot searching algorithm. + + Examples + ======== + + >>> from sympy import Matrix + >>> a = Matrix([[4, 3], [6, 3]]) + >>> L, U, _ = a.LUdecomposition() + >>> L + Matrix([ + [ 1, 0], + [3/2, 1]]) + >>> U + Matrix([ + [4, 3], + [0, -3/2]]) + + See Also + ======== + + sympy.matrices.dense.DenseMatrix.cholesky + sympy.matrices.dense.DenseMatrix.LDLdecomposition + QRdecomposition + LUdecomposition_Simple + LUdecompositionFF + LUsolve + """ + + combined, p = M.LUdecomposition_Simple(iszerofunc=iszerofunc, + simpfunc=simpfunc, rankcheck=rankcheck) + + # L is lower triangular ``M.rows x M.rows`` + # U is upper triangular ``M.rows x M.cols`` + # L has unit diagonal. For each column in combined, the subcolumn + # below the diagonal of combined is shared by L. + # If L has more columns than combined, then the remaining subcolumns + # below the diagonal of L are zero. + # The upper triangular portion of L and combined are equal. + def entry_L(i, j): + if i < j: + # Super diagonal entry + return M.zero + elif i == j: + return M.one + elif j < combined.cols: + return combined[i, j] + + # Subdiagonal entry of L with no corresponding + # entry in combined + return M.zero + + def entry_U(i, j): + return M.zero if i > j else combined[i, j] + + L = M._new(combined.rows, combined.rows, entry_L) + U = M._new(combined.rows, combined.cols, entry_U) + + return L, U, p + +def _LUdecomposition_Simple(M, iszerofunc=_iszero, simpfunc=None, + rankcheck=False): + r"""Compute the PLU decomposition of the matrix. + + Parameters + ========== + + rankcheck : bool, optional + Determines if this function should detect the rank + deficiency of the matrixis and should raise a + ``ValueError``. + + iszerofunc : function, optional + A function which determines if a given expression is zero. + + The function should be a callable that takes a single + SymPy expression and returns a 3-valued boolean value + ``True``, ``False``, or ``None``. + + It is internally used by the pivot searching algorithm. + See the notes section for a more information about the + pivot searching algorithm. + + simpfunc : function or None, optional + A function that simplifies the input. + + If this is specified as a function, this function should be + a callable that takes a single SymPy expression and returns + an another SymPy expression that is algebraically + equivalent. + + If ``None``, it indicates that the pivot search algorithm + should not attempt to simplify any candidate pivots. + + It is internally used by the pivot searching algorithm. + See the notes section for a more information about the + pivot searching algorithm. + + Returns + ======= + + (lu, row_swaps) : (Matrix, list) + If the original matrix is a $m, n$ matrix: + + *lu* is a $m, n$ matrix, which contains result of the + decomposition in a compressed form. See the notes section + to see how the matrix is compressed. + + *row_swaps* is a $m$-element list where each element is a + pair of row exchange indices. + + ``A = (L*U).permute_backward(perm)``, and the row + permutation matrix $P$ from the formula $P A = L U$ can be + computed by ``P=eye(A.row).permute_forward(perm)``. + + Raises + ====== + + ValueError + Raised if ``rankcheck=True`` and the matrix is found to + be rank deficient during the computation. + + Notes + ===== + + About the PLU decomposition: + + PLU decomposition is a generalization of a LU decomposition + which can be extended for rank-deficient matrices. + + It can further be generalized for non-square matrices, and this + is the notation that SymPy is using. + + PLU decomposition is a decomposition of a $m, n$ matrix $A$ in + the form of $P A = L U$ where + + * $L$ is a $m, m$ lower triangular matrix with unit diagonal + entries. + * $U$ is a $m, n$ upper triangular matrix. + * $P$ is a $m, m$ permutation matrix. + + So, for a square matrix, the decomposition would look like: + + .. math:: + L = \begin{bmatrix} + 1 & 0 & 0 & \cdots & 0 \\ + L_{1, 0} & 1 & 0 & \cdots & 0 \\ + L_{2, 0} & L_{2, 1} & 1 & \cdots & 0 \\ + \vdots & \vdots & \vdots & \ddots & \vdots \\ + L_{n-1, 0} & L_{n-1, 1} & L_{n-1, 2} & \cdots & 1 + \end{bmatrix} + + .. math:: + U = \begin{bmatrix} + U_{0, 0} & U_{0, 1} & U_{0, 2} & \cdots & U_{0, n-1} \\ + 0 & U_{1, 1} & U_{1, 2} & \cdots & U_{1, n-1} \\ + 0 & 0 & U_{2, 2} & \cdots & U_{2, n-1} \\ + \vdots & \vdots & \vdots & \ddots & \vdots \\ + 0 & 0 & 0 & \cdots & U_{n-1, n-1} + \end{bmatrix} + + And for a matrix with more rows than the columns, + the decomposition would look like: + + .. math:: + L = \begin{bmatrix} + 1 & 0 & 0 & \cdots & 0 & 0 & \cdots & 0 \\ + L_{1, 0} & 1 & 0 & \cdots & 0 & 0 & \cdots & 0 \\ + L_{2, 0} & L_{2, 1} & 1 & \cdots & 0 & 0 & \cdots & 0 \\ + \vdots & \vdots & \vdots & \ddots & \vdots & \vdots & \ddots + & \vdots \\ + L_{n-1, 0} & L_{n-1, 1} & L_{n-1, 2} & \cdots & 1 & 0 + & \cdots & 0 \\ + L_{n, 0} & L_{n, 1} & L_{n, 2} & \cdots & L_{n, n-1} & 1 + & \cdots & 0 \\ + \vdots & \vdots & \vdots & \ddots & \vdots & \vdots + & \ddots & \vdots \\ + L_{m-1, 0} & L_{m-1, 1} & L_{m-1, 2} & \cdots & L_{m-1, n-1} + & 0 & \cdots & 1 \\ + \end{bmatrix} + + .. math:: + U = \begin{bmatrix} + U_{0, 0} & U_{0, 1} & U_{0, 2} & \cdots & U_{0, n-1} \\ + 0 & U_{1, 1} & U_{1, 2} & \cdots & U_{1, n-1} \\ + 0 & 0 & U_{2, 2} & \cdots & U_{2, n-1} \\ + \vdots & \vdots & \vdots & \ddots & \vdots \\ + 0 & 0 & 0 & \cdots & U_{n-1, n-1} \\ + 0 & 0 & 0 & \cdots & 0 \\ + \vdots & \vdots & \vdots & \ddots & \vdots \\ + 0 & 0 & 0 & \cdots & 0 + \end{bmatrix} + + Finally, for a matrix with more columns than the rows, the + decomposition would look like: + + .. math:: + L = \begin{bmatrix} + 1 & 0 & 0 & \cdots & 0 \\ + L_{1, 0} & 1 & 0 & \cdots & 0 \\ + L_{2, 0} & L_{2, 1} & 1 & \cdots & 0 \\ + \vdots & \vdots & \vdots & \ddots & \vdots \\ + L_{m-1, 0} & L_{m-1, 1} & L_{m-1, 2} & \cdots & 1 + \end{bmatrix} + + .. math:: + U = \begin{bmatrix} + U_{0, 0} & U_{0, 1} & U_{0, 2} & \cdots & U_{0, m-1} + & \cdots & U_{0, n-1} \\ + 0 & U_{1, 1} & U_{1, 2} & \cdots & U_{1, m-1} + & \cdots & U_{1, n-1} \\ + 0 & 0 & U_{2, 2} & \cdots & U_{2, m-1} + & \cdots & U_{2, n-1} \\ + \vdots & \vdots & \vdots & \ddots & \vdots + & \cdots & \vdots \\ + 0 & 0 & 0 & \cdots & U_{m-1, m-1} + & \cdots & U_{m-1, n-1} \\ + \end{bmatrix} + + About the compressed LU storage: + + The results of the decomposition are often stored in compressed + forms rather than returning $L$ and $U$ matrices individually. + + It may be less intiuitive, but it is commonly used for a lot of + numeric libraries because of the efficiency. + + The storage matrix is defined as following for this specific + method: + + * The subdiagonal elements of $L$ are stored in the subdiagonal + portion of $LU$, that is $LU_{i, j} = L_{i, j}$ whenever + $i > j$. + * The elements on the diagonal of $L$ are all 1, and are not + explicitly stored. + * $U$ is stored in the upper triangular portion of $LU$, that is + $LU_{i, j} = U_{i, j}$ whenever $i <= j$. + * For a case of $m > n$, the right side of the $L$ matrix is + trivial to store. + * For a case of $m < n$, the below side of the $U$ matrix is + trivial to store. + + So, for a square matrix, the compressed output matrix would be: + + .. math:: + LU = \begin{bmatrix} + U_{0, 0} & U_{0, 1} & U_{0, 2} & \cdots & U_{0, n-1} \\ + L_{1, 0} & U_{1, 1} & U_{1, 2} & \cdots & U_{1, n-1} \\ + L_{2, 0} & L_{2, 1} & U_{2, 2} & \cdots & U_{2, n-1} \\ + \vdots & \vdots & \vdots & \ddots & \vdots \\ + L_{n-1, 0} & L_{n-1, 1} & L_{n-1, 2} & \cdots & U_{n-1, n-1} + \end{bmatrix} + + For a matrix with more rows than the columns, the compressed + output matrix would be: + + .. math:: + LU = \begin{bmatrix} + U_{0, 0} & U_{0, 1} & U_{0, 2} & \cdots & U_{0, n-1} \\ + L_{1, 0} & U_{1, 1} & U_{1, 2} & \cdots & U_{1, n-1} \\ + L_{2, 0} & L_{2, 1} & U_{2, 2} & \cdots & U_{2, n-1} \\ + \vdots & \vdots & \vdots & \ddots & \vdots \\ + L_{n-1, 0} & L_{n-1, 1} & L_{n-1, 2} & \cdots + & U_{n-1, n-1} \\ + \vdots & \vdots & \vdots & \ddots & \vdots \\ + L_{m-1, 0} & L_{m-1, 1} & L_{m-1, 2} & \cdots + & L_{m-1, n-1} \\ + \end{bmatrix} + + For a matrix with more columns than the rows, the compressed + output matrix would be: + + .. math:: + LU = \begin{bmatrix} + U_{0, 0} & U_{0, 1} & U_{0, 2} & \cdots & U_{0, m-1} + & \cdots & U_{0, n-1} \\ + L_{1, 0} & U_{1, 1} & U_{1, 2} & \cdots & U_{1, m-1} + & \cdots & U_{1, n-1} \\ + L_{2, 0} & L_{2, 1} & U_{2, 2} & \cdots & U_{2, m-1} + & \cdots & U_{2, n-1} \\ + \vdots & \vdots & \vdots & \ddots & \vdots + & \cdots & \vdots \\ + L_{m-1, 0} & L_{m-1, 1} & L_{m-1, 2} & \cdots & U_{m-1, m-1} + & \cdots & U_{m-1, n-1} \\ + \end{bmatrix} + + About the pivot searching algorithm: + + When a matrix contains symbolic entries, the pivot search algorithm + differs from the case where every entry can be categorized as zero or + nonzero. + The algorithm searches column by column through the submatrix whose + top left entry coincides with the pivot position. + If it exists, the pivot is the first entry in the current search + column that iszerofunc guarantees is nonzero. + If no such candidate exists, then each candidate pivot is simplified + if simpfunc is not None. + The search is repeated, with the difference that a candidate may be + the pivot if ``iszerofunc()`` cannot guarantee that it is nonzero. + In the second search the pivot is the first candidate that + iszerofunc can guarantee is nonzero. + If no such candidate exists, then the pivot is the first candidate + for which iszerofunc returns None. + If no such candidate exists, then the search is repeated in the next + column to the right. + The pivot search algorithm differs from the one in ``rref()``, which + relies on ``_find_reasonable_pivot()``. + Future versions of ``LUdecomposition_simple()`` may use + ``_find_reasonable_pivot()``. + + See Also + ======== + + sympy.matrices.matrixbase.MatrixBase.LUdecomposition + LUdecompositionFF + LUsolve + """ + + if rankcheck: + # https://github.com/sympy/sympy/issues/9796 + pass + + if S.Zero in M.shape: + # Define LU decomposition of a matrix with no entries as a matrix + # of the same dimensions with all zero entries. + return M.zeros(M.rows, M.cols), [] + + dps = _get_intermediate_simp() + lu = M.as_mutable() + row_swaps = [] + + pivot_col = 0 + + for pivot_row in range(0, lu.rows - 1): + # Search for pivot. Prefer entry that iszeropivot determines + # is nonzero, over entry that iszeropivot cannot guarantee + # is zero. + # XXX ``_find_reasonable_pivot`` uses slow zero testing. Blocked by bug #10279 + # Future versions of LUdecomposition_simple can pass iszerofunc and simpfunc + # to _find_reasonable_pivot(). + # In pass 3 of _find_reasonable_pivot(), the predicate in ``if x.equals(S.Zero):`` + # calls sympy.simplify(), and not the simplification function passed in via + # the keyword argument simpfunc. + iszeropivot = True + + while pivot_col != M.cols and iszeropivot: + sub_col = (lu[r, pivot_col] for r in range(pivot_row, M.rows)) + + pivot_row_offset, pivot_value, is_assumed_non_zero, ind_simplified_pairs =\ + _find_reasonable_pivot_naive(sub_col, iszerofunc, simpfunc) + + iszeropivot = pivot_value is None + + if iszeropivot: + # All candidate pivots in this column are zero. + # Proceed to next column. + pivot_col += 1 + + if rankcheck and pivot_col != pivot_row: + # All entries including and below the pivot position are + # zero, which indicates that the rank of the matrix is + # strictly less than min(num rows, num cols) + # Mimic behavior of previous implementation, by throwing a + # ValueError. + raise ValueError("Rank of matrix is strictly less than" + " number of rows or columns." + " Pass keyword argument" + " rankcheck=False to compute" + " the LU decomposition of this matrix.") + + candidate_pivot_row = None if pivot_row_offset is None else pivot_row + pivot_row_offset + + if candidate_pivot_row is None and iszeropivot: + # If candidate_pivot_row is None and iszeropivot is True + # after pivot search has completed, then the submatrix + # below and to the right of (pivot_row, pivot_col) is + # all zeros, indicating that Gaussian elimination is + # complete. + return lu, row_swaps + + # Update entries simplified during pivot search. + for offset, val in ind_simplified_pairs: + lu[pivot_row + offset, pivot_col] = val + + if pivot_row != candidate_pivot_row: + # Row swap book keeping: + # Record which rows were swapped. + # Update stored portion of L factor by multiplying L on the + # left and right with the current permutation. + # Swap rows of U. + row_swaps.append([pivot_row, candidate_pivot_row]) + + # Update L. + lu[pivot_row, 0:pivot_row], lu[candidate_pivot_row, 0:pivot_row] = \ + lu[candidate_pivot_row, 0:pivot_row], lu[pivot_row, 0:pivot_row] + + # Swap pivot row of U with candidate pivot row. + lu[pivot_row, pivot_col:lu.cols], lu[candidate_pivot_row, pivot_col:lu.cols] = \ + lu[candidate_pivot_row, pivot_col:lu.cols], lu[pivot_row, pivot_col:lu.cols] + + # Introduce zeros below the pivot by adding a multiple of the + # pivot row to a row under it, and store the result in the + # row under it. + # Only entries in the target row whose index is greater than + # start_col may be nonzero. + start_col = pivot_col + 1 + + for row in range(pivot_row + 1, lu.rows): + # Store factors of L in the subcolumn below + # (pivot_row, pivot_row). + lu[row, pivot_row] = \ + dps(lu[row, pivot_col]/lu[pivot_row, pivot_col]) + + # Form the linear combination of the pivot row and the current + # row below the pivot row that zeros the entries below the pivot. + # Employing slicing instead of a loop here raises + # NotImplementedError: Cannot add Zero to MutableSparseMatrix + # in sympy/matrices/tests/test_sparse.py. + # c = pivot_row + 1 if pivot_row == pivot_col else pivot_col + for c in range(start_col, lu.cols): + lu[row, c] = dps(lu[row, c] - lu[row, pivot_row]*lu[pivot_row, c]) + + if pivot_row != pivot_col: + # matrix rank < min(num rows, num cols), + # so factors of L are not stored directly below the pivot. + # These entries are zero by construction, so don't bother + # computing them. + for row in range(pivot_row + 1, lu.rows): + lu[row, pivot_col] = M.zero + + pivot_col += 1 + + if pivot_col == lu.cols: + # All candidate pivots are zero implies that Gaussian + # elimination is complete. + return lu, row_swaps + + if rankcheck: + if iszerofunc( + lu[Min(lu.rows, lu.cols) - 1, Min(lu.rows, lu.cols) - 1]): + raise ValueError("Rank of matrix is strictly less than" + " number of rows or columns." + " Pass keyword argument" + " rankcheck=False to compute" + " the LU decomposition of this matrix.") + + return lu, row_swaps + +def _LUdecompositionFF(M): + """Compute a fraction-free LU decomposition. + + Returns 4 matrices P, L, D, U such that PA = L D**-1 U. + If the elements of the matrix belong to some integral domain I, then all + elements of L, D and U are guaranteed to belong to I. + + See Also + ======== + + sympy.matrices.matrixbase.MatrixBase.LUdecomposition + LUdecomposition_Simple + LUsolve + + References + ========== + + .. [1] W. Zhou & D.J. Jeffrey, "Fraction-free matrix factors: new forms + for LU and QR factors". Frontiers in Computer Science in China, + Vol 2, no. 1, pp. 67-80, 2008. + """ + + from sympy.matrices import SparseMatrix + + zeros = SparseMatrix.zeros + eye = SparseMatrix.eye + n, m = M.rows, M.cols + U, L, P = M.as_mutable(), eye(n), eye(n) + DD = zeros(n, n) + oldpivot = 1 + + for k in range(n - 1): + if U[k, k] == 0: + for kpivot in range(k + 1, n): + if U[kpivot, k]: + break + else: + raise ValueError("Matrix is not full rank") + + U[k, k:], U[kpivot, k:] = U[kpivot, k:], U[k, k:] + L[k, :k], L[kpivot, :k] = L[kpivot, :k], L[k, :k] + P[k, :], P[kpivot, :] = P[kpivot, :], P[k, :] + + L [k, k] = Ukk = U[k, k] + DD[k, k] = oldpivot * Ukk + + for i in range(k + 1, n): + L[i, k] = Uik = U[i, k] + + for j in range(k + 1, m): + U[i, j] = (Ukk * U[i, j] - U[k, j] * Uik) / oldpivot + + U[i, k] = 0 + + oldpivot = Ukk + + DD[n - 1, n - 1] = oldpivot + + return P, L, DD, U + +def _singular_value_decomposition(A): + r"""Returns a Condensed Singular Value decomposition. + + Explanation + =========== + + A Singular Value decomposition is a decomposition in the form $A = U \Sigma V^H$ + where + + - $U, V$ are column orthogonal matrix. + - $\Sigma$ is a diagonal matrix, where the main diagonal contains singular + values of matrix A. + + A column orthogonal matrix satisfies + $\mathbb{I} = U^H U$ while a full orthogonal matrix satisfies + relation $\mathbb{I} = U U^H = U^H U$ where $\mathbb{I}$ is an identity + matrix with matching dimensions. + + For matrices which are not square or are rank-deficient, it is + sufficient to return a column orthogonal matrix because augmenting + them may introduce redundant computations. + In condensed Singular Value Decomposition we only return column orthogonal + matrices because of this reason + + If you want to augment the results to return a full orthogonal + decomposition, you should use the following procedures. + + - Augment the $U, V$ matrices with columns that are orthogonal to every + other columns and make it square. + - Augment the $\Sigma$ matrix with zero rows to make it have the same + shape as the original matrix. + + The procedure will be illustrated in the examples section. + + Examples + ======== + + we take a full rank matrix first: + + >>> from sympy import Matrix + >>> A = Matrix([[1, 2],[2,1]]) + >>> U, S, V = A.singular_value_decomposition() + >>> U + Matrix([ + [ sqrt(2)/2, sqrt(2)/2], + [-sqrt(2)/2, sqrt(2)/2]]) + >>> S + Matrix([ + [1, 0], + [0, 3]]) + >>> V + Matrix([ + [-sqrt(2)/2, sqrt(2)/2], + [ sqrt(2)/2, sqrt(2)/2]]) + + If a matrix if square and full rank both U, V + are orthogonal in both directions + + >>> U * U.H + Matrix([ + [1, 0], + [0, 1]]) + >>> U.H * U + Matrix([ + [1, 0], + [0, 1]]) + + >>> V * V.H + Matrix([ + [1, 0], + [0, 1]]) + >>> V.H * V + Matrix([ + [1, 0], + [0, 1]]) + >>> A == U * S * V.H + True + + >>> C = Matrix([ + ... [1, 0, 0, 0, 2], + ... [0, 0, 3, 0, 0], + ... [0, 0, 0, 0, 0], + ... [0, 2, 0, 0, 0], + ... ]) + >>> U, S, V = C.singular_value_decomposition() + + >>> V.H * V + Matrix([ + [1, 0, 0], + [0, 1, 0], + [0, 0, 1]]) + >>> V * V.H + Matrix([ + [1/5, 0, 0, 0, 2/5], + [ 0, 1, 0, 0, 0], + [ 0, 0, 1, 0, 0], + [ 0, 0, 0, 0, 0], + [2/5, 0, 0, 0, 4/5]]) + + If you want to augment the results to be a full orthogonal + decomposition, you should augment $V$ with an another orthogonal + column. + + You are able to append an arbitrary standard basis that are linearly + independent to every other columns and you can run the Gram-Schmidt + process to make them augmented as orthogonal basis. + + >>> V_aug = V.row_join(Matrix([[0,0,0,0,1], + ... [0,0,0,1,0]]).H) + >>> V_aug = V_aug.QRdecomposition()[0] + >>> V_aug + Matrix([ + [0, sqrt(5)/5, 0, -2*sqrt(5)/5, 0], + [1, 0, 0, 0, 0], + [0, 0, 1, 0, 0], + [0, 0, 0, 0, 1], + [0, 2*sqrt(5)/5, 0, sqrt(5)/5, 0]]) + >>> V_aug.H * V_aug + Matrix([ + [1, 0, 0, 0, 0], + [0, 1, 0, 0, 0], + [0, 0, 1, 0, 0], + [0, 0, 0, 1, 0], + [0, 0, 0, 0, 1]]) + >>> V_aug * V_aug.H + Matrix([ + [1, 0, 0, 0, 0], + [0, 1, 0, 0, 0], + [0, 0, 1, 0, 0], + [0, 0, 0, 1, 0], + [0, 0, 0, 0, 1]]) + + Similarly we augment U + + >>> U_aug = U.row_join(Matrix([0,0,1,0])) + >>> U_aug = U_aug.QRdecomposition()[0] + >>> U_aug + Matrix([ + [0, 1, 0, 0], + [0, 0, 1, 0], + [0, 0, 0, 1], + [1, 0, 0, 0]]) + + >>> U_aug.H * U_aug + Matrix([ + [1, 0, 0, 0], + [0, 1, 0, 0], + [0, 0, 1, 0], + [0, 0, 0, 1]]) + >>> U_aug * U_aug.H + Matrix([ + [1, 0, 0, 0], + [0, 1, 0, 0], + [0, 0, 1, 0], + [0, 0, 0, 1]]) + + We add 2 zero columns and one row to S + + >>> S_aug = S.col_join(Matrix([[0,0,0]])) + >>> S_aug = S_aug.row_join(Matrix([[0,0,0,0], + ... [0,0,0,0]]).H) + >>> S_aug + Matrix([ + [2, 0, 0, 0, 0], + [0, sqrt(5), 0, 0, 0], + [0, 0, 3, 0, 0], + [0, 0, 0, 0, 0]]) + + + + >>> U_aug * S_aug * V_aug.H == C + True + + """ + + AH = A.H + m, n = A.shape + if m >= n: + V, S = (AH * A).diagonalize() + + ranked = [] + for i, x in enumerate(S.diagonal()): + if not x.is_zero: + ranked.append(i) + + V = V[:, ranked] + + Singular_vals = [sqrt(S[i, i]) for i in range(S.rows) if i in ranked] + + S = S.diag(*Singular_vals) + V, _ = V.QRdecomposition() + U = A * V * S.inv() + else: + U, S = (A * AH).diagonalize() + + ranked = [] + for i, x in enumerate(S.diagonal()): + if not x.is_zero: + ranked.append(i) + + U = U[:, ranked] + Singular_vals = [sqrt(S[i, i]) for i in range(S.rows) if i in ranked] + + S = S.diag(*Singular_vals) + U, _ = U.QRdecomposition() + V = AH * U * S.inv() + + return U, S, V + +def _QRdecomposition_optional(M, normalize=True): + def dot(u, v): + return u.dot(v, hermitian=True) + + dps = _get_intermediate_simp(expand_mul, expand_mul) + + A = M.as_mutable() + ranked = [] + + Q = A + R = A.zeros(A.cols) + + for j in range(A.cols): + for i in range(j): + if Q[:, i].is_zero_matrix: + continue + + R[i, j] = dot(Q[:, i], Q[:, j]) / dot(Q[:, i], Q[:, i]) + R[i, j] = dps(R[i, j]) + Q[:, j] -= Q[:, i] * R[i, j] + + Q[:, j] = dps(Q[:, j]) + if Q[:, j].is_zero_matrix is not True: + ranked.append(j) + R[j, j] = M.one + + Q = Q.extract(range(Q.rows), ranked) + R = R.extract(ranked, range(R.cols)) + + if normalize: + # Normalization + for i in range(Q.cols): + norm = Q[:, i].norm() + Q[:, i] /= norm + R[i, :] *= norm + + return M.__class__(Q), M.__class__(R) + + +def _QRdecomposition(M): + r"""Returns a QR decomposition. + + Explanation + =========== + + A QR decomposition is a decomposition in the form $A = Q R$ + where + + - $Q$ is a column orthogonal matrix. + - $R$ is a upper triangular (trapezoidal) matrix. + + A column orthogonal matrix satisfies + $\mathbb{I} = Q^H Q$ while a full orthogonal matrix satisfies + relation $\mathbb{I} = Q Q^H = Q^H Q$ where $I$ is an identity + matrix with matching dimensions. + + For matrices which are not square or are rank-deficient, it is + sufficient to return a column orthogonal matrix because augmenting + them may introduce redundant computations. + And an another advantage of this is that you can easily inspect the + matrix rank by counting the number of columns of $Q$. + + If you want to augment the results to return a full orthogonal + decomposition, you should use the following procedures. + + - Augment the $Q$ matrix with columns that are orthogonal to every + other columns and make it square. + - Augment the $R$ matrix with zero rows to make it have the same + shape as the original matrix. + + The procedure will be illustrated in the examples section. + + Examples + ======== + + A full rank matrix example: + + >>> from sympy import Matrix + >>> A = Matrix([[12, -51, 4], [6, 167, -68], [-4, 24, -41]]) + >>> Q, R = A.QRdecomposition() + >>> Q + Matrix([ + [ 6/7, -69/175, -58/175], + [ 3/7, 158/175, 6/175], + [-2/7, 6/35, -33/35]]) + >>> R + Matrix([ + [14, 21, -14], + [ 0, 175, -70], + [ 0, 0, 35]]) + + If the matrix is square and full rank, the $Q$ matrix becomes + orthogonal in both directions, and needs no augmentation. + + >>> Q * Q.H + Matrix([ + [1, 0, 0], + [0, 1, 0], + [0, 0, 1]]) + >>> Q.H * Q + Matrix([ + [1, 0, 0], + [0, 1, 0], + [0, 0, 1]]) + + >>> A == Q*R + True + + A rank deficient matrix example: + + >>> A = Matrix([[12, -51, 0], [6, 167, 0], [-4, 24, 0]]) + >>> Q, R = A.QRdecomposition() + >>> Q + Matrix([ + [ 6/7, -69/175], + [ 3/7, 158/175], + [-2/7, 6/35]]) + >>> R + Matrix([ + [14, 21, 0], + [ 0, 175, 0]]) + + QRdecomposition might return a matrix Q that is rectangular. + In this case the orthogonality condition might be satisfied as + $\mathbb{I} = Q.H*Q$ but not in the reversed product + $\mathbb{I} = Q * Q.H$. + + >>> Q.H * Q + Matrix([ + [1, 0], + [0, 1]]) + >>> Q * Q.H + Matrix([ + [27261/30625, 348/30625, -1914/6125], + [ 348/30625, 30589/30625, 198/6125], + [ -1914/6125, 198/6125, 136/1225]]) + + If you want to augment the results to be a full orthogonal + decomposition, you should augment $Q$ with an another orthogonal + column. + + You are able to append an identity matrix, + and you can run the Gram-Schmidt + process to make them augmented as orthogonal basis. + + >>> Q_aug = Q.row_join(Matrix.eye(3)) + >>> Q_aug = Q_aug.QRdecomposition()[0] + >>> Q_aug + Matrix([ + [ 6/7, -69/175, 58/175], + [ 3/7, 158/175, -6/175], + [-2/7, 6/35, 33/35]]) + >>> Q_aug.H * Q_aug + Matrix([ + [1, 0, 0], + [0, 1, 0], + [0, 0, 1]]) + >>> Q_aug * Q_aug.H + Matrix([ + [1, 0, 0], + [0, 1, 0], + [0, 0, 1]]) + + Augmenting the $R$ matrix with zero row is straightforward. + + >>> R_aug = R.col_join(Matrix([[0, 0, 0]])) + >>> R_aug + Matrix([ + [14, 21, 0], + [ 0, 175, 0], + [ 0, 0, 0]]) + >>> Q_aug * R_aug == A + True + + A zero matrix example: + + >>> from sympy import Matrix + >>> A = Matrix.zeros(3, 4) + >>> Q, R = A.QRdecomposition() + + They may return matrices with zero rows and columns. + + >>> Q + Matrix(3, 0, []) + >>> R + Matrix(0, 4, []) + >>> Q*R + Matrix([ + [0, 0, 0, 0], + [0, 0, 0, 0], + [0, 0, 0, 0]]) + + As the same augmentation rule described above, $Q$ can be augmented + with columns of an identity matrix and $R$ can be augmented with + rows of a zero matrix. + + >>> Q_aug = Q.row_join(Matrix.eye(3)) + >>> R_aug = R.col_join(Matrix.zeros(3, 4)) + >>> Q_aug * Q_aug.T + Matrix([ + [1, 0, 0], + [0, 1, 0], + [0, 0, 1]]) + >>> R_aug + Matrix([ + [0, 0, 0, 0], + [0, 0, 0, 0], + [0, 0, 0, 0]]) + >>> Q_aug * R_aug == A + True + + See Also + ======== + + sympy.matrices.dense.DenseMatrix.cholesky + sympy.matrices.dense.DenseMatrix.LDLdecomposition + sympy.matrices.matrixbase.MatrixBase.LUdecomposition + QRsolve + """ + return _QRdecomposition_optional(M, normalize=True) + +def _upper_hessenberg_decomposition(A): + """Converts a matrix into Hessenberg matrix H. + + Returns 2 matrices H, P s.t. + $P H P^{T} = A$, where H is an upper hessenberg matrix + and P is an orthogonal matrix + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix([ + ... [1,2,3], + ... [-3,5,6], + ... [4,-8,9], + ... ]) + >>> H, P = A.upper_hessenberg_decomposition() + >>> H + Matrix([ + [1, 6/5, 17/5], + [5, 213/25, -134/25], + [0, 216/25, 137/25]]) + >>> P + Matrix([ + [1, 0, 0], + [0, -3/5, 4/5], + [0, 4/5, 3/5]]) + >>> P * H * P.H == A + True + + + References + ========== + + .. [#] https://mathworld.wolfram.com/HessenbergDecomposition.html + """ + + M = A.as_mutable() + + if not M.is_square: + raise NonSquareMatrixError("Matrix must be square.") + + n = M.cols + P = M.eye(n) + H = M + + for j in range(n - 2): + + u = H[j + 1:, j] + + if u[1:, :].is_zero_matrix: + continue + + if sign(u[0]) != 0: + u[0] = u[0] + sign(u[0]) * u.norm() + else: + u[0] = u[0] + u.norm() + + v = u / u.norm() + + H[j + 1:, :] = H[j + 1:, :] - 2 * v * (v.H * H[j + 1:, :]) + H[:, j + 1:] = H[:, j + 1:] - (H[:, j + 1:] * (2 * v)) * v.H + P[:, j + 1:] = P[:, j + 1:] - (P[:, j + 1:] * (2 * v)) * v.H + + return H, P diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/dense.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/dense.py new file mode 100644 index 0000000000000000000000000000000000000000..98bf9931df54f67abfd9c4dc810b46fdcf70288f --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/dense.py @@ -0,0 +1,1094 @@ +from __future__ import annotations +import random + +from sympy.core.basic import Basic +from sympy.core.singleton import S +from sympy.core.symbol import Symbol +from sympy.core.sympify import sympify +from sympy.functions.elementary.trigonometric import cos, sin +from sympy.utilities.decorator import doctest_depends_on +from sympy.utilities.exceptions import sympy_deprecation_warning +from sympy.utilities.iterables import is_sequence + +from .exceptions import ShapeError +from .decompositions import _cholesky, _LDLdecomposition +from .matrixbase import MatrixBase +from .repmatrix import MutableRepMatrix, RepMatrix +from .solvers import _lower_triangular_solve, _upper_triangular_solve + + +__doctest_requires__ = {('symarray',): ['numpy']} + + +def _iszero(x): + """Returns True if x is zero.""" + return x.is_zero + + +class DenseMatrix(RepMatrix): + """Matrix implementation based on DomainMatrix as the internal representation""" + + # + # DenseMatrix is a superclass for both MutableDenseMatrix and + # ImmutableDenseMatrix. Methods shared by both classes but not for the + # Sparse classes should be implemented here. + # + + is_MatrixExpr: bool = False + + _op_priority = 10.01 + _class_priority = 4 + + @property + def _mat(self): + sympy_deprecation_warning( + """ + The private _mat attribute of Matrix is deprecated. Use the + .flat() method instead. + """, + deprecated_since_version="1.9", + active_deprecations_target="deprecated-private-matrix-attributes" + ) + + return self.flat() + + def _eval_inverse(self, **kwargs): + return self.inv(method=kwargs.get('method', 'GE'), + iszerofunc=kwargs.get('iszerofunc', _iszero), + try_block_diag=kwargs.get('try_block_diag', False)) + + def as_immutable(self): + """Returns an Immutable version of this Matrix + """ + from .immutable import ImmutableDenseMatrix as cls + return cls._fromrep(self._rep.copy()) + + def as_mutable(self): + """Returns a mutable version of this matrix + + Examples + ======== + + >>> from sympy import ImmutableMatrix + >>> X = ImmutableMatrix([[1, 2], [3, 4]]) + >>> Y = X.as_mutable() + >>> Y[1, 1] = 5 # Can set values in Y + >>> Y + Matrix([ + [1, 2], + [3, 5]]) + """ + return Matrix(self) + + def cholesky(self, hermitian=True): + return _cholesky(self, hermitian=hermitian) + + def LDLdecomposition(self, hermitian=True): + return _LDLdecomposition(self, hermitian=hermitian) + + def lower_triangular_solve(self, rhs): + return _lower_triangular_solve(self, rhs) + + def upper_triangular_solve(self, rhs): + return _upper_triangular_solve(self, rhs) + + cholesky.__doc__ = _cholesky.__doc__ + LDLdecomposition.__doc__ = _LDLdecomposition.__doc__ + lower_triangular_solve.__doc__ = _lower_triangular_solve.__doc__ + upper_triangular_solve.__doc__ = _upper_triangular_solve.__doc__ + + +def _force_mutable(x): + """Return a matrix as a Matrix, otherwise return x.""" + if getattr(x, 'is_Matrix', False): + return x.as_mutable() + elif isinstance(x, Basic): + return x + elif hasattr(x, '__array__'): + a = x.__array__() + if len(a.shape) == 0: + return sympify(a) + return Matrix(x) + return x + + +class MutableDenseMatrix(DenseMatrix, MutableRepMatrix): + + def simplify(self, **kwargs): + """Applies simplify to the elements of a matrix in place. + + This is a shortcut for M.applyfunc(lambda x: simplify(x, ratio, measure)) + + See Also + ======== + + sympy.simplify.simplify.simplify + """ + from sympy.simplify.simplify import simplify as _simplify + for (i, j), element in self.todok().items(): + self[i, j] = _simplify(element, **kwargs) + + +MutableMatrix = Matrix = MutableDenseMatrix + +########### +# Numpy Utility Functions: +# list2numpy, matrix2numpy, symmarray +########### + + +def list2numpy(l, dtype=object): # pragma: no cover + """Converts Python list of SymPy expressions to a NumPy array. + + See Also + ======== + + matrix2numpy + """ + from numpy import empty + a = empty(len(l), dtype) + for i, s in enumerate(l): + a[i] = s + return a + + +def matrix2numpy(m, dtype=object): # pragma: no cover + """Converts SymPy's matrix to a NumPy array. + + See Also + ======== + + list2numpy + """ + from numpy import empty + a = empty(m.shape, dtype) + for i in range(m.rows): + for j in range(m.cols): + a[i, j] = m[i, j] + return a + + +########### +# Rotation matrices: +# rot_givens, rot_axis[123], rot_ccw_axis[123] +########### + + +def rot_givens(i, j, theta, dim=3): + r"""Returns a a Givens rotation matrix, a a rotation in the + plane spanned by two coordinates axes. + + Explanation + =========== + + The Givens rotation corresponds to a generalization of rotation + matrices to any number of dimensions, given by: + + .. math:: + G(i, j, \theta) = + \begin{bmatrix} + 1 & \cdots & 0 & \cdots & 0 & \cdots & 0 \\ + \vdots & \ddots & \vdots & & \vdots & & \vdots \\ + 0 & \cdots & c & \cdots & -s & \cdots & 0 \\ + \vdots & & \vdots & \ddots & \vdots & & \vdots \\ + 0 & \cdots & s & \cdots & c & \cdots & 0 \\ + \vdots & & \vdots & & \vdots & \ddots & \vdots \\ + 0 & \cdots & 0 & \cdots & 0 & \cdots & 1 + \end{bmatrix} + + Where $c = \cos(\theta)$ and $s = \sin(\theta)$ appear at the intersections + ``i``\th and ``j``\th rows and columns. + + For fixed ``i > j``\, the non-zero elements of a Givens matrix are + given by: + + - $g_{kk} = 1$ for $k \ne i,\,j$ + - $g_{kk} = c$ for $k = i,\,j$ + - $g_{ji} = -g_{ij} = -s$ + + Parameters + ========== + + i : int between ``0`` and ``dim - 1`` + Represents first axis + j : int between ``0`` and ``dim - 1`` + Represents second axis + dim : int bigger than 1 + Number of dimensions. Defaults to 3. + + Examples + ======== + + >>> from sympy import pi, rot_givens + + A counterclockwise rotation of pi/3 (60 degrees) around + the third axis (z-axis): + + >>> rot_givens(1, 0, pi/3) + Matrix([ + [ 1/2, -sqrt(3)/2, 0], + [sqrt(3)/2, 1/2, 0], + [ 0, 0, 1]]) + + If we rotate by pi/2 (90 degrees): + + >>> rot_givens(1, 0, pi/2) + Matrix([ + [0, -1, 0], + [1, 0, 0], + [0, 0, 1]]) + + This can be generalized to any number + of dimensions: + + >>> rot_givens(1, 0, pi/2, dim=4) + Matrix([ + [0, -1, 0, 0], + [1, 0, 0, 0], + [0, 0, 1, 0], + [0, 0, 0, 1]]) + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Givens_rotation + + See Also + ======== + + rot_axis1: Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis (clockwise around the x axis) + rot_axis2: Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis (clockwise around the y axis) + rot_axis3: Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis (clockwise around the z axis) + rot_ccw_axis1: Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis (counterclockwise around the x axis) + rot_ccw_axis2: Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis (counterclockwise around the y axis) + rot_ccw_axis3: Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis (counterclockwise around the z axis) + """ + if not isinstance(dim, int) or dim < 2: + raise ValueError('dim must be an integer biggen than one, ' + 'got {}.'.format(dim)) + + if i == j: + raise ValueError('i and j must be different, ' + 'got ({}, {})'.format(i, j)) + + for ij in [i, j]: + if not isinstance(ij, int) or ij < 0 or ij > dim - 1: + raise ValueError('i and j must be integers between 0 and ' + '{}, got i={} and j={}.'.format(dim-1, i, j)) + + theta = sympify(theta) + c = cos(theta) + s = sin(theta) + M = eye(dim) + M[i, i] = c + M[j, j] = c + M[i, j] = s + M[j, i] = -s + return M + + +def rot_axis3(theta): + r"""Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis. + + Explanation + =========== + + For a right-handed coordinate system, this corresponds to a + clockwise rotation around the `z`-axis, given by: + + .. math:: + + R = \begin{bmatrix} + \cos(\theta) & \sin(\theta) & 0 \\ + -\sin(\theta) & \cos(\theta) & 0 \\ + 0 & 0 & 1 + \end{bmatrix} + + Examples + ======== + + >>> from sympy import pi, rot_axis3 + + A rotation of pi/3 (60 degrees): + + >>> theta = pi/3 + >>> rot_axis3(theta) + Matrix([ + [ 1/2, sqrt(3)/2, 0], + [-sqrt(3)/2, 1/2, 0], + [ 0, 0, 1]]) + + If we rotate by pi/2 (90 degrees): + + >>> rot_axis3(pi/2) + Matrix([ + [ 0, 1, 0], + [-1, 0, 0], + [ 0, 0, 1]]) + + See Also + ======== + + rot_givens: Returns a Givens rotation matrix (generalized rotation for + any number of dimensions) + rot_ccw_axis3: Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis (counterclockwise around the z axis) + rot_axis1: Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis (clockwise around the x axis) + rot_axis2: Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis (clockwise around the y axis) + """ + return rot_givens(0, 1, theta, dim=3) + + +def rot_axis2(theta): + r"""Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis. + + Explanation + =========== + + For a right-handed coordinate system, this corresponds to a + clockwise rotation around the `y`-axis, given by: + + .. math:: + + R = \begin{bmatrix} + \cos(\theta) & 0 & -\sin(\theta) \\ + 0 & 1 & 0 \\ + \sin(\theta) & 0 & \cos(\theta) + \end{bmatrix} + + Examples + ======== + + >>> from sympy import pi, rot_axis2 + + A rotation of pi/3 (60 degrees): + + >>> theta = pi/3 + >>> rot_axis2(theta) + Matrix([ + [ 1/2, 0, -sqrt(3)/2], + [ 0, 1, 0], + [sqrt(3)/2, 0, 1/2]]) + + If we rotate by pi/2 (90 degrees): + + >>> rot_axis2(pi/2) + Matrix([ + [0, 0, -1], + [0, 1, 0], + [1, 0, 0]]) + + See Also + ======== + + rot_givens: Returns a Givens rotation matrix (generalized rotation for + any number of dimensions) + rot_ccw_axis2: Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis (clockwise around the y axis) + rot_axis1: Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis (counterclockwise around the x axis) + rot_axis3: Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis (counterclockwise around the z axis) + """ + return rot_givens(2, 0, theta, dim=3) + + +def rot_axis1(theta): + r"""Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis. + + Explanation + =========== + + For a right-handed coordinate system, this corresponds to a + clockwise rotation around the `x`-axis, given by: + + .. math:: + + R = \begin{bmatrix} + 1 & 0 & 0 \\ + 0 & \cos(\theta) & \sin(\theta) \\ + 0 & -\sin(\theta) & \cos(\theta) + \end{bmatrix} + + Examples + ======== + + >>> from sympy import pi, rot_axis1 + + A rotation of pi/3 (60 degrees): + + >>> theta = pi/3 + >>> rot_axis1(theta) + Matrix([ + [1, 0, 0], + [0, 1/2, sqrt(3)/2], + [0, -sqrt(3)/2, 1/2]]) + + If we rotate by pi/2 (90 degrees): + + >>> rot_axis1(pi/2) + Matrix([ + [1, 0, 0], + [0, 0, 1], + [0, -1, 0]]) + + See Also + ======== + + rot_givens: Returns a Givens rotation matrix (generalized rotation for + any number of dimensions) + rot_ccw_axis1: Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis (counterclockwise around the x axis) + rot_axis2: Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis (clockwise around the y axis) + rot_axis3: Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis (clockwise around the z axis) + """ + return rot_givens(1, 2, theta, dim=3) + + +def rot_ccw_axis3(theta): + r"""Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis. + + Explanation + =========== + + For a right-handed coordinate system, this corresponds to a + counterclockwise rotation around the `z`-axis, given by: + + .. math:: + + R = \begin{bmatrix} + \cos(\theta) & -\sin(\theta) & 0 \\ + \sin(\theta) & \cos(\theta) & 0 \\ + 0 & 0 & 1 + \end{bmatrix} + + Examples + ======== + + >>> from sympy import pi, rot_ccw_axis3 + + A rotation of pi/3 (60 degrees): + + >>> theta = pi/3 + >>> rot_ccw_axis3(theta) + Matrix([ + [ 1/2, -sqrt(3)/2, 0], + [sqrt(3)/2, 1/2, 0], + [ 0, 0, 1]]) + + If we rotate by pi/2 (90 degrees): + + >>> rot_ccw_axis3(pi/2) + Matrix([ + [0, -1, 0], + [1, 0, 0], + [0, 0, 1]]) + + See Also + ======== + + rot_givens: Returns a Givens rotation matrix (generalized rotation for + any number of dimensions) + rot_axis3: Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis (clockwise around the z axis) + rot_ccw_axis1: Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis (counterclockwise around the x axis) + rot_ccw_axis2: Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis (counterclockwise around the y axis) + """ + return rot_givens(1, 0, theta, dim=3) + + +def rot_ccw_axis2(theta): + r"""Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis. + + Explanation + =========== + + For a right-handed coordinate system, this corresponds to a + counterclockwise rotation around the `y`-axis, given by: + + .. math:: + + R = \begin{bmatrix} + \cos(\theta) & 0 & \sin(\theta) \\ + 0 & 1 & 0 \\ + -\sin(\theta) & 0 & \cos(\theta) + \end{bmatrix} + + Examples + ======== + + >>> from sympy import pi, rot_ccw_axis2 + + A rotation of pi/3 (60 degrees): + + >>> theta = pi/3 + >>> rot_ccw_axis2(theta) + Matrix([ + [ 1/2, 0, sqrt(3)/2], + [ 0, 1, 0], + [-sqrt(3)/2, 0, 1/2]]) + + If we rotate by pi/2 (90 degrees): + + >>> rot_ccw_axis2(pi/2) + Matrix([ + [ 0, 0, 1], + [ 0, 1, 0], + [-1, 0, 0]]) + + See Also + ======== + + rot_givens: Returns a Givens rotation matrix (generalized rotation for + any number of dimensions) + rot_axis2: Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis (clockwise around the y axis) + rot_ccw_axis1: Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis (counterclockwise around the x axis) + rot_ccw_axis3: Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis (counterclockwise around the z axis) + """ + return rot_givens(0, 2, theta, dim=3) + + +def rot_ccw_axis1(theta): + r"""Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis. + + Explanation + =========== + + For a right-handed coordinate system, this corresponds to a + counterclockwise rotation around the `x`-axis, given by: + + .. math:: + + R = \begin{bmatrix} + 1 & 0 & 0 \\ + 0 & \cos(\theta) & -\sin(\theta) \\ + 0 & \sin(\theta) & \cos(\theta) + \end{bmatrix} + + Examples + ======== + + >>> from sympy import pi, rot_ccw_axis1 + + A rotation of pi/3 (60 degrees): + + >>> theta = pi/3 + >>> rot_ccw_axis1(theta) + Matrix([ + [1, 0, 0], + [0, 1/2, -sqrt(3)/2], + [0, sqrt(3)/2, 1/2]]) + + If we rotate by pi/2 (90 degrees): + + >>> rot_ccw_axis1(pi/2) + Matrix([ + [1, 0, 0], + [0, 0, -1], + [0, 1, 0]]) + + See Also + ======== + + rot_givens: Returns a Givens rotation matrix (generalized rotation for + any number of dimensions) + rot_axis1: Returns a rotation matrix for a rotation of theta (in radians) + about the 1-axis (clockwise around the x axis) + rot_ccw_axis2: Returns a rotation matrix for a rotation of theta (in radians) + about the 2-axis (counterclockwise around the y axis) + rot_ccw_axis3: Returns a rotation matrix for a rotation of theta (in radians) + about the 3-axis (counterclockwise around the z axis) + """ + return rot_givens(2, 1, theta, dim=3) + + +@doctest_depends_on(modules=('numpy',)) +def symarray(prefix, shape, **kwargs): # pragma: no cover + r"""Create a numpy ndarray of symbols (as an object array). + + The created symbols are named ``prefix_i1_i2_``... You should thus provide a + non-empty prefix if you want your symbols to be unique for different output + arrays, as SymPy symbols with identical names are the same object. + + Parameters + ---------- + + prefix : string + A prefix prepended to the name of every symbol. + + shape : int or tuple + Shape of the created array. If an int, the array is one-dimensional; for + more than one dimension the shape must be a tuple. + + \*\*kwargs : dict + keyword arguments passed on to Symbol + + Examples + ======== + These doctests require numpy. + + >>> from sympy import symarray + >>> symarray('', 3) + [_0 _1 _2] + + If you want multiple symarrays to contain distinct symbols, you *must* + provide unique prefixes: + + >>> a = symarray('', 3) + >>> b = symarray('', 3) + >>> a[0] == b[0] + True + >>> a = symarray('a', 3) + >>> b = symarray('b', 3) + >>> a[0] == b[0] + False + + Creating symarrays with a prefix: + + >>> symarray('a', 3) + [a_0 a_1 a_2] + + For more than one dimension, the shape must be given as a tuple: + + >>> symarray('a', (2, 3)) + [[a_0_0 a_0_1 a_0_2] + [a_1_0 a_1_1 a_1_2]] + >>> symarray('a', (2, 3, 2)) + [[[a_0_0_0 a_0_0_1] + [a_0_1_0 a_0_1_1] + [a_0_2_0 a_0_2_1]] + + [[a_1_0_0 a_1_0_1] + [a_1_1_0 a_1_1_1] + [a_1_2_0 a_1_2_1]]] + + For setting assumptions of the underlying Symbols: + + >>> [s.is_real for s in symarray('a', 2, real=True)] + [True, True] + """ + from numpy import empty, ndindex + arr = empty(shape, dtype=object) + for index in ndindex(shape): + arr[index] = Symbol('%s_%s' % (prefix, '_'.join(map(str, index))), + **kwargs) + return arr + + +############### +# Functions +############### + +def casoratian(seqs, n, zero=True): + """Given linear difference operator L of order 'k' and homogeneous + equation Ly = 0 we want to compute kernel of L, which is a set + of 'k' sequences: a(n), b(n), ... z(n). + + Solutions of L are linearly independent iff their Casoratian, + denoted as C(a, b, ..., z), do not vanish for n = 0. + + Casoratian is defined by k x k determinant:: + + + a(n) b(n) . . . z(n) + + | a(n+1) b(n+1) . . . z(n+1) | + | . . . . | + | . . . . | + | . . . . | + + a(n+k-1) b(n+k-1) . . . z(n+k-1) + + + It proves very useful in rsolve_hyper() where it is applied + to a generating set of a recurrence to factor out linearly + dependent solutions and return a basis: + + >>> from sympy import Symbol, casoratian, factorial + >>> n = Symbol('n', integer=True) + + Exponential and factorial are linearly independent: + + >>> casoratian([2**n, factorial(n)], n) != 0 + True + + """ + + seqs = list(map(sympify, seqs)) + + if not zero: + f = lambda i, j: seqs[j].subs(n, n + i) + else: + f = lambda i, j: seqs[j].subs(n, i) + + k = len(seqs) + + return Matrix(k, k, f).det() + + +def eye(*args, **kwargs): + """Create square identity matrix n x n + + See Also + ======== + + diag + zeros + ones + """ + + return Matrix.eye(*args, **kwargs) + + +def diag(*values, strict=True, unpack=False, **kwargs): + """Returns a matrix with the provided values placed on the + diagonal. If non-square matrices are included, they will + produce a block-diagonal matrix. + + Examples + ======== + + This version of diag is a thin wrapper to Matrix.diag that differs + in that it treats all lists like matrices -- even when a single list + is given. If this is not desired, either put a `*` before the list or + set `unpack=True`. + + >>> from sympy import diag + + >>> diag([1, 2, 3], unpack=True) # = diag(1,2,3) or diag(*[1,2,3]) + Matrix([ + [1, 0, 0], + [0, 2, 0], + [0, 0, 3]]) + + >>> diag([1, 2, 3]) # a column vector + Matrix([ + [1], + [2], + [3]]) + + See Also + ======== + .matrixbase.MatrixBase.eye + .matrixbase.MatrixBase.diagonal + .matrixbase.MatrixBase.diag + .expressions.blockmatrix.BlockMatrix + """ + return Matrix.diag(*values, strict=strict, unpack=unpack, **kwargs) + + +def GramSchmidt(vlist, orthonormal=False): + """Apply the Gram-Schmidt process to a set of vectors. + + Parameters + ========== + + vlist : List of Matrix + Vectors to be orthogonalized for. + + orthonormal : Bool, optional + If true, return an orthonormal basis. + + Returns + ======= + + vlist : List of Matrix + Orthogonalized vectors + + Notes + ===== + + This routine is mostly duplicate from ``Matrix.orthogonalize``, + except for some difference that this always raises error when + linearly dependent vectors are found, and the keyword ``normalize`` + has been named as ``orthonormal`` in this function. + + See Also + ======== + + .matrixbase.MatrixBase.orthogonalize + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Gram%E2%80%93Schmidt_process + """ + return MutableDenseMatrix.orthogonalize( + *vlist, normalize=orthonormal, rankcheck=True + ) + + +def hessian(f, varlist, constraints=()): + """Compute Hessian matrix for a function f wrt parameters in varlist + which may be given as a sequence or a row/column vector. A list of + constraints may optionally be given. + + Examples + ======== + + >>> from sympy import Function, hessian, pprint + >>> from sympy.abc import x, y + >>> f = Function('f')(x, y) + >>> g1 = Function('g')(x, y) + >>> g2 = x**2 + 3*y + >>> pprint(hessian(f, (x, y), [g1, g2])) + [ d d ] + [ 0 0 --(g(x, y)) --(g(x, y)) ] + [ dx dy ] + [ ] + [ 0 0 2*x 3 ] + [ ] + [ 2 2 ] + [d d d ] + [--(g(x, y)) 2*x ---(f(x, y)) -----(f(x, y))] + [dx 2 dy dx ] + [ dx ] + [ ] + [ 2 2 ] + [d d d ] + [--(g(x, y)) 3 -----(f(x, y)) ---(f(x, y)) ] + [dy dy dx 2 ] + [ dy ] + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Hessian_matrix + + See Also + ======== + + sympy.matrices.matrixbase.MatrixBase.jacobian + wronskian + """ + # f is the expression representing a function f, return regular matrix + if isinstance(varlist, MatrixBase): + if 1 not in varlist.shape: + raise ShapeError("`varlist` must be a column or row vector.") + if varlist.cols == 1: + varlist = varlist.T + varlist = varlist.tolist()[0] + if is_sequence(varlist): + n = len(varlist) + if not n: + raise ShapeError("`len(varlist)` must not be zero.") + else: + raise ValueError("Improper variable list in hessian function") + if not getattr(f, 'diff'): + # check differentiability + raise ValueError("Function `f` (%s) is not differentiable" % f) + m = len(constraints) + N = m + n + out = zeros(N) + for k, g in enumerate(constraints): + if not getattr(g, 'diff'): + # check differentiability + raise ValueError("Function `f` (%s) is not differentiable" % f) + for i in range(n): + out[k, i + m] = g.diff(varlist[i]) + for i in range(n): + for j in range(i, n): + out[i + m, j + m] = f.diff(varlist[i]).diff(varlist[j]) + for i in range(N): + for j in range(i + 1, N): + out[j, i] = out[i, j] + return out + + +def jordan_cell(eigenval, n): + """ + Create a Jordan block: + + Examples + ======== + + >>> from sympy import jordan_cell + >>> from sympy.abc import x + >>> jordan_cell(x, 4) + Matrix([ + [x, 1, 0, 0], + [0, x, 1, 0], + [0, 0, x, 1], + [0, 0, 0, x]]) + """ + + return Matrix.jordan_block(size=n, eigenvalue=eigenval) + + +def matrix_multiply_elementwise(A, B): + """Return the Hadamard product (elementwise product) of A and B + + >>> from sympy import Matrix, matrix_multiply_elementwise + >>> A = Matrix([[0, 1, 2], [3, 4, 5]]) + >>> B = Matrix([[1, 10, 100], [100, 10, 1]]) + >>> matrix_multiply_elementwise(A, B) + Matrix([ + [ 0, 10, 200], + [300, 40, 5]]) + + See Also + ======== + + sympy.matrices.matrixbase.MatrixBase.__mul__ + """ + return A.multiply_elementwise(B) + + +def ones(*args, **kwargs): + """Returns a matrix of ones with ``rows`` rows and ``cols`` columns; + if ``cols`` is omitted a square matrix will be returned. + + See Also + ======== + + zeros + eye + diag + """ + + if 'c' in kwargs: + kwargs['cols'] = kwargs.pop('c') + + return Matrix.ones(*args, **kwargs) + + +def randMatrix(r, c=None, min=0, max=99, seed=None, symmetric=False, + percent=100, prng=None): + """Create random matrix with dimensions ``r`` x ``c``. If ``c`` is omitted + the matrix will be square. If ``symmetric`` is True the matrix must be + square. If ``percent`` is less than 100 then only approximately the given + percentage of elements will be non-zero. + + The pseudo-random number generator used to generate matrix is chosen in the + following way. + + * If ``prng`` is supplied, it will be used as random number generator. + It should be an instance of ``random.Random``, or at least have + ``randint`` and ``shuffle`` methods with same signatures. + * if ``prng`` is not supplied but ``seed`` is supplied, then new + ``random.Random`` with given ``seed`` will be created; + * otherwise, a new ``random.Random`` with default seed will be used. + + Examples + ======== + + >>> from sympy import randMatrix + >>> randMatrix(3) # doctest:+SKIP + [25, 45, 27] + [44, 54, 9] + [23, 96, 46] + >>> randMatrix(3, 2) # doctest:+SKIP + [87, 29] + [23, 37] + [90, 26] + >>> randMatrix(3, 3, 0, 2) # doctest:+SKIP + [0, 2, 0] + [2, 0, 1] + [0, 0, 1] + >>> randMatrix(3, symmetric=True) # doctest:+SKIP + [85, 26, 29] + [26, 71, 43] + [29, 43, 57] + >>> A = randMatrix(3, seed=1) + >>> B = randMatrix(3, seed=2) + >>> A == B + False + >>> A == randMatrix(3, seed=1) + True + >>> randMatrix(3, symmetric=True, percent=50) # doctest:+SKIP + [77, 70, 0], + [70, 0, 0], + [ 0, 0, 88] + """ + # Note that ``Random()`` is equivalent to ``Random(None)`` + prng = prng or random.Random(seed) + + if c is None: + c = r + + if symmetric and r != c: + raise ValueError('For symmetric matrices, r must equal c, but %i != %i' % (r, c)) + + ij = range(r * c) + if percent != 100: + ij = prng.sample(ij, int(len(ij)*percent // 100)) + + m = zeros(r, c) + + if not symmetric: + for ijk in ij: + i, j = divmod(ijk, c) + m[i, j] = prng.randint(min, max) + else: + for ijk in ij: + i, j = divmod(ijk, c) + if i <= j: + m[i, j] = m[j, i] = prng.randint(min, max) + + return m + + +def wronskian(functions, var, method='bareiss'): + """ + Compute Wronskian for [] of functions + + :: + + | f1 f2 ... fn | + | f1' f2' ... fn' | + | . . . . | + W(f1, ..., fn) = | . . . . | + | . . . . | + | (n) (n) (n) | + | D (f1) D (f2) ... D (fn) | + + see: https://en.wikipedia.org/wiki/Wronskian + + See Also + ======== + + sympy.matrices.matrixbase.MatrixBase.jacobian + hessian + """ + + functions = [sympify(f) for f in functions] + n = len(functions) + if n == 0: + return S.One + W = Matrix(n, n, lambda i, j: functions[i].diff(var, j)) + return W.det(method) + + +def zeros(*args, **kwargs): + """Returns a matrix of zeros with ``rows`` rows and ``cols`` columns; + if ``cols`` is omitted a square matrix will be returned. + + See Also + ======== + + ones + eye + diag + """ + + if 'c' in kwargs: + kwargs['cols'] = kwargs.pop('c') + + return Matrix.zeros(*args, **kwargs) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/determinant.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/determinant.py new file mode 100644 index 0000000000000000000000000000000000000000..9206c0714999ebe0cde5c4300d9b3293939177df --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/determinant.py @@ -0,0 +1,1021 @@ +from types import FunctionType + +from sympy.core.cache import cacheit +from sympy.core.numbers import Float, Integer +from sympy.core.singleton import S +from sympy.core.symbol import uniquely_named_symbol +from sympy.core.mul import Mul +from sympy.polys import PurePoly, cancel +from sympy.functions.combinatorial.numbers import nC +from sympy.polys.matrices.domainmatrix import DomainMatrix +from sympy.polys.matrices.ddm import DDM + +from .exceptions import NonSquareMatrixError +from .utilities import ( + _get_intermediate_simp, _get_intermediate_simp_bool, + _iszero, _is_zero_after_expand_mul, _dotprodsimp, _simplify) + + +def _find_reasonable_pivot(col, iszerofunc=_iszero, simpfunc=_simplify): + """ Find the lowest index of an item in ``col`` that is + suitable for a pivot. If ``col`` consists only of + Floats, the pivot with the largest norm is returned. + Otherwise, the first element where ``iszerofunc`` returns + False is used. If ``iszerofunc`` does not return false, + items are simplified and retested until a suitable + pivot is found. + + Returns a 4-tuple + (pivot_offset, pivot_val, assumed_nonzero, newly_determined) + where pivot_offset is the index of the pivot, pivot_val is + the (possibly simplified) value of the pivot, assumed_nonzero + is True if an assumption that the pivot was non-zero + was made without being proved, and newly_determined are + elements that were simplified during the process of pivot + finding.""" + + newly_determined = [] + col = list(col) + # a column that contains a mix of floats and integers + # but at least one float is considered a numerical + # column, and so we do partial pivoting + if all(isinstance(x, (Float, Integer)) for x in col) and any( + isinstance(x, Float) for x in col): + col_abs = [abs(x) for x in col] + max_value = max(col_abs) + if iszerofunc(max_value): + # just because iszerofunc returned True, doesn't + # mean the value is numerically zero. Make sure + # to replace all entries with numerical zeros + if max_value != 0: + newly_determined = [(i, 0) for i, x in enumerate(col) if x != 0] + return (None, None, False, newly_determined) + index = col_abs.index(max_value) + return (index, col[index], False, newly_determined) + + # PASS 1 (iszerofunc directly) + possible_zeros = [] + for i, x in enumerate(col): + is_zero = iszerofunc(x) + # is someone wrote a custom iszerofunc, it may return + # BooleanFalse or BooleanTrue instead of True or False, + # so use == for comparison instead of `is` + if is_zero == False: + # we found something that is definitely not zero + return (i, x, False, newly_determined) + possible_zeros.append(is_zero) + + # by this point, we've found no certain non-zeros + if all(possible_zeros): + # if everything is definitely zero, we have + # no pivot + return (None, None, False, newly_determined) + + # PASS 2 (iszerofunc after simplify) + # we haven't found any for-sure non-zeros, so + # go through the elements iszerofunc couldn't + # make a determination about and opportunistically + # simplify to see if we find something + for i, x in enumerate(col): + if possible_zeros[i] is not None: + continue + simped = simpfunc(x) + is_zero = iszerofunc(simped) + if is_zero in (True, False): + newly_determined.append((i, simped)) + if is_zero == False: + return (i, simped, False, newly_determined) + possible_zeros[i] = is_zero + + # after simplifying, some things that were recognized + # as zeros might be zeros + if all(possible_zeros): + # if everything is definitely zero, we have + # no pivot + return (None, None, False, newly_determined) + + # PASS 3 (.equals(0)) + # some expressions fail to simplify to zero, but + # ``.equals(0)`` evaluates to True. As a last-ditch + # attempt, apply ``.equals`` to these expressions + for i, x in enumerate(col): + if possible_zeros[i] is not None: + continue + if x.equals(S.Zero): + # ``.iszero`` may return False with + # an implicit assumption (e.g., ``x.equals(0)`` + # when ``x`` is a symbol), so only treat it + # as proved when ``.equals(0)`` returns True + possible_zeros[i] = True + newly_determined.append((i, S.Zero)) + + if all(possible_zeros): + return (None, None, False, newly_determined) + + # at this point there is nothing that could definitely + # be a pivot. To maintain compatibility with existing + # behavior, we'll assume that an illdetermined thing is + # non-zero. We should probably raise a warning in this case + i = possible_zeros.index(None) + return (i, col[i], True, newly_determined) + + +def _find_reasonable_pivot_naive(col, iszerofunc=_iszero, simpfunc=None): + """ + Helper that computes the pivot value and location from a + sequence of contiguous matrix column elements. As a side effect + of the pivot search, this function may simplify some of the elements + of the input column. A list of these simplified entries and their + indices are also returned. + This function mimics the behavior of _find_reasonable_pivot(), + but does less work trying to determine if an indeterminate candidate + pivot simplifies to zero. This more naive approach can be much faster, + with the trade-off that it may erroneously return a pivot that is zero. + + ``col`` is a sequence of contiguous column entries to be searched for + a suitable pivot. + ``iszerofunc`` is a callable that returns a Boolean that indicates + if its input is zero, or None if no such determination can be made. + ``simpfunc`` is a callable that simplifies its input. It must return + its input if it does not simplify its input. Passing in + ``simpfunc=None`` indicates that the pivot search should not attempt + to simplify any candidate pivots. + + Returns a 4-tuple: + (pivot_offset, pivot_val, assumed_nonzero, newly_determined) + ``pivot_offset`` is the sequence index of the pivot. + ``pivot_val`` is the value of the pivot. + pivot_val and col[pivot_index] are equivalent, but will be different + when col[pivot_index] was simplified during the pivot search. + ``assumed_nonzero`` is a boolean indicating if the pivot cannot be + guaranteed to be zero. If assumed_nonzero is true, then the pivot + may or may not be non-zero. If assumed_nonzero is false, then + the pivot is non-zero. + ``newly_determined`` is a list of index-value pairs of pivot candidates + that were simplified during the pivot search. + """ + + # indeterminates holds the index-value pairs of each pivot candidate + # that is neither zero or non-zero, as determined by iszerofunc(). + # If iszerofunc() indicates that a candidate pivot is guaranteed + # non-zero, or that every candidate pivot is zero then the contents + # of indeterminates are unused. + # Otherwise, the only viable candidate pivots are symbolic. + # In this case, indeterminates will have at least one entry, + # and all but the first entry are ignored when simpfunc is None. + indeterminates = [] + for i, col_val in enumerate(col): + col_val_is_zero = iszerofunc(col_val) + if col_val_is_zero == False: + # This pivot candidate is non-zero. + return i, col_val, False, [] + elif col_val_is_zero is None: + # The candidate pivot's comparison with zero + # is indeterminate. + indeterminates.append((i, col_val)) + + if len(indeterminates) == 0: + # All candidate pivots are guaranteed to be zero, i.e. there is + # no pivot. + return None, None, False, [] + + if simpfunc is None: + # Caller did not pass in a simplification function that might + # determine if an indeterminate pivot candidate is guaranteed + # to be nonzero, so assume the first indeterminate candidate + # is non-zero. + return indeterminates[0][0], indeterminates[0][1], True, [] + + # newly_determined holds index-value pairs of candidate pivots + # that were simplified during the search for a non-zero pivot. + newly_determined = [] + for i, col_val in indeterminates: + tmp_col_val = simpfunc(col_val) + if id(col_val) != id(tmp_col_val): + # simpfunc() simplified this candidate pivot. + newly_determined.append((i, tmp_col_val)) + if iszerofunc(tmp_col_val) == False: + # Candidate pivot simplified to a guaranteed non-zero value. + return i, tmp_col_val, False, newly_determined + + return indeterminates[0][0], indeterminates[0][1], True, newly_determined + + +# This functions is a candidate for caching if it gets implemented for matrices. +def _berkowitz_toeplitz_matrix(M): + """Return (A,T) where T the Toeplitz matrix used in the Berkowitz algorithm + corresponding to ``M`` and A is the first principal submatrix. + """ + + # the 0 x 0 case is trivial + if M.rows == 0 and M.cols == 0: + return M._new(1,1, [M.one]) + + # + # Partition M = [ a_11 R ] + # [ C A ] + # + + a, R = M[0,0], M[0, 1:] + C, A = M[1:, 0], M[1:,1:] + + # + # The Toeplitz matrix looks like + # + # [ 1 ] + # [ -a 1 ] + # [ -RC -a 1 ] + # [ -RAC -RC -a 1 ] + # [ -RA**2C -RAC -RC -a 1 ] + # etc. + + # Compute the diagonal entries. + # Because multiplying matrix times vector is so much + # more efficient than matrix times matrix, recursively + # compute -R * A**n * C. + diags = [C] + for i in range(M.rows - 2): + diags.append(A.multiply(diags[i], dotprodsimp=None)) + diags = [(-R).multiply(d, dotprodsimp=None)[0, 0] for d in diags] + diags = [M.one, -a] + diags + + def entry(i,j): + if j > i: + return M.zero + return diags[i - j] + + toeplitz = M._new(M.cols + 1, M.rows, entry) + return (A, toeplitz) + + +# This functions is a candidate for caching if it gets implemented for matrices. +def _berkowitz_vector(M): + """ Run the Berkowitz algorithm and return a vector whose entries + are the coefficients of the characteristic polynomial of ``M``. + + Given N x N matrix, efficiently compute + coefficients of characteristic polynomials of ``M`` + without division in the ground domain. + + This method is particularly useful for computing determinant, + principal minors and characteristic polynomial when ``M`` + has complicated coefficients e.g. polynomials. Semi-direct + usage of this algorithm is also important in computing + efficiently sub-resultant PRS. + + Assuming that M is a square matrix of dimension N x N and + I is N x N identity matrix, then the Berkowitz vector is + an N x 1 vector whose entries are coefficients of the + polynomial + + charpoly(M) = det(t*I - M) + + As a consequence, all polynomials generated by Berkowitz + algorithm are monic. + + For more information on the implemented algorithm refer to: + + [1] S.J. Berkowitz, On computing the determinant in small + parallel time using a small number of processors, ACM, + Information Processing Letters 18, 1984, pp. 147-150 + + [2] M. Keber, Division-Free computation of sub-resultants + using Bezout matrices, Tech. Report MPI-I-2006-1-006, + Saarbrucken, 2006 + """ + + # handle the trivial cases + if M.rows == 0 and M.cols == 0: + return M._new(1, 1, [M.one]) + elif M.rows == 1 and M.cols == 1: + return M._new(2, 1, [M.one, -M[0,0]]) + + submat, toeplitz = _berkowitz_toeplitz_matrix(M) + + return toeplitz.multiply(_berkowitz_vector(submat), dotprodsimp=None) + + +def _adjugate(M, method="berkowitz"): + """Returns the adjugate, or classical adjoint, of + a matrix. That is, the transpose of the matrix of cofactors. + + https://en.wikipedia.org/wiki/Adjugate + + Parameters + ========== + + method : string, optional + Method to use to find the cofactors, can be "bareiss", "berkowitz", + "bird", "laplace" or "lu". + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix([[1, 2], [3, 4]]) + >>> M.adjugate() + Matrix([ + [ 4, -2], + [-3, 1]]) + + See Also + ======== + + cofactor_matrix + sympy.matrices.matrixbase.MatrixBase.transpose + """ + + return M.cofactor_matrix(method=method).transpose() + + +# This functions is a candidate for caching if it gets implemented for matrices. +def _charpoly(M, x='lambda', simplify=_simplify): + """Computes characteristic polynomial det(x*I - M) where I is + the identity matrix. + + A PurePoly is returned, so using different variables for ``x`` does + not affect the comparison or the polynomials: + + Parameters + ========== + + x : string, optional + Name for the "lambda" variable, defaults to "lambda". + + simplify : function, optional + Simplification function to use on the characteristic polynomial + calculated. Defaults to ``simplify``. + + Examples + ======== + + >>> from sympy import Matrix + >>> from sympy.abc import x, y + >>> M = Matrix([[1, 3], [2, 0]]) + >>> M.charpoly() + PurePoly(lambda**2 - lambda - 6, lambda, domain='ZZ') + >>> M.charpoly(x) == M.charpoly(y) + True + >>> M.charpoly(x) == M.charpoly(y) + True + + Specifying ``x`` is optional; a symbol named ``lambda`` is used by + default (which looks good when pretty-printed in unicode): + + >>> M.charpoly().as_expr() + lambda**2 - lambda - 6 + + And if ``x`` clashes with an existing symbol, underscores will + be prepended to the name to make it unique: + + >>> M = Matrix([[1, 2], [x, 0]]) + >>> M.charpoly(x).as_expr() + _x**2 - _x - 2*x + + Whether you pass a symbol or not, the generator can be obtained + with the gen attribute since it may not be the same as the symbol + that was passed: + + >>> M.charpoly(x).gen + _x + >>> M.charpoly(x).gen == x + False + + Notes + ===== + + The Samuelson-Berkowitz algorithm is used to compute + the characteristic polynomial efficiently and without any + division operations. Thus the characteristic polynomial over any + commutative ring without zero divisors can be computed. + + If the determinant det(x*I - M) can be found out easily as + in the case of an upper or a lower triangular matrix, then + instead of Samuelson-Berkowitz algorithm, eigenvalues are computed + and the characteristic polynomial with their help. + + See Also + ======== + + det + """ + + if not M.is_square: + raise NonSquareMatrixError() + + # Use DomainMatrix. We are already going to convert this to a Poly so there + # is no need to worry about expanding powers etc. Also since this algorithm + # does not require division or zero detection it is fine to use EX. + # + # M.to_DM() will fall back on EXRAW rather than EX. EXRAW is a lot faster + # for elementary arithmetic because it does not call cancel for each + # operation but it generates large unsimplified results that are slow in + # the subsequent call to simplify. Using EX instead is faster overall + # but at least in some cases EXRAW+simplify gives a simpler result so we + # preserve that existing behaviour of charpoly for now... + dM = M.to_DM() + + K = dM.domain + + cp = dM.charpoly() + + x = uniquely_named_symbol(x, [M], modify=lambda s: '_' + s) + + if K.is_EXRAW or simplify is not _simplify: + # XXX: Converting back to Expr is expensive. We only do it if the + # caller supplied a custom simplify function for backwards + # compatibility or otherwise if the domain was EX. For any other domain + # there should be no benefit in simplifying at this stage because Poly + # will put everything into canonical form anyway. + berk_vector = [K.to_sympy(c) for c in cp] + berk_vector = [simplify(a) for a in berk_vector] + p = PurePoly(berk_vector, x) + + else: + # Convert from the list of domain elements directly to Poly. + p = PurePoly(cp, x, domain=K) + + return p + + +def _cofactor(M, i, j, method="berkowitz"): + """Calculate the cofactor of an element. + + Parameters + ========== + + method : string, optional + Method to use to find the cofactors, can be "bareiss", "berkowitz", + "bird", "laplace" or "lu". + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix([[1, 2], [3, 4]]) + >>> M.cofactor(0, 1) + -3 + + See Also + ======== + + cofactor_matrix + minor + minor_submatrix + """ + + if not M.is_square or M.rows < 1: + raise NonSquareMatrixError() + + return S.NegativeOne**((i + j) % 2) * M.minor(i, j, method) + + +def _cofactor_matrix(M, method="berkowitz"): + """Return a matrix containing the cofactor of each element. + + Parameters + ========== + + method : string, optional + Method to use to find the cofactors, can be "bareiss", "berkowitz", + "bird", "laplace" or "lu". + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix([[1, 2], [3, 4]]) + >>> M.cofactor_matrix() + Matrix([ + [ 4, -3], + [-2, 1]]) + + See Also + ======== + + cofactor + minor + minor_submatrix + """ + + if not M.is_square: + raise NonSquareMatrixError() + + return M._new(M.rows, M.cols, + lambda i, j: M.cofactor(i, j, method)) + +def _per(M): + """Returns the permanent of a matrix. Unlike determinant, + permanent is defined for both square and non-square matrices. + + For an m x n matrix, with m less than or equal to n, + it is given as the sum over the permutations s of size + less than or equal to m on [1, 2, . . . n] of the product + from i = 1 to m of M[i, s[i]]. Taking the transpose will + not affect the value of the permanent. + + In the case of a square matrix, this is the same as the permutation + definition of the determinant, but it does not take the sign of the + permutation into account. Computing the permanent with this definition + is quite inefficient, so here the Ryser formula is used. + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) + >>> M.per() + 450 + >>> M = Matrix([1, 5, 7]) + >>> M.per() + 13 + + References + ========== + + .. [1] Prof. Frank Ben's notes: https://math.berkeley.edu/~bernd/ban275.pdf + .. [2] Wikipedia article on Permanent: https://en.wikipedia.org/wiki/Permanent_%28mathematics%29 + .. [3] https://reference.wolfram.com/language/ref/Permanent.html + .. [4] Permanent of a rectangular matrix : https://arxiv.org/pdf/0904.3251.pdf + """ + import itertools + + m, n = M.shape + if m > n: + M = M.T + m, n = n, m + s = list(range(n)) + + subsets = [] + for i in range(1, m + 1): + subsets += list(map(list, itertools.combinations(s, i))) + + perm = 0 + for subset in subsets: + prod = 1 + sub_len = len(subset) + for i in range(m): + prod *= sum(M[i, j] for j in subset) + perm += prod * S.NegativeOne**sub_len * nC(n - sub_len, m - sub_len) + perm *= S.NegativeOne**m + return perm.simplify() + +def _det_DOM(M): + DOM = DomainMatrix.from_Matrix(M, field=True, extension=True) + K = DOM.domain + return K.to_sympy(DOM.det()) + +# This functions is a candidate for caching if it gets implemented for matrices. +def _det(M, method="bareiss", iszerofunc=None): + """Computes the determinant of a matrix if ``M`` is a concrete matrix object + otherwise return an expressions ``Determinant(M)`` if ``M`` is a + ``MatrixSymbol`` or other expression. + + Parameters + ========== + + method : string, optional + Specifies the algorithm used for computing the matrix determinant. + + If the matrix is at most 3x3, a hard-coded formula is used and the + specified method is ignored. Otherwise, it defaults to + ``'bareiss'``. + + Also, if the matrix is an upper or a lower triangular matrix, determinant + is computed by simple multiplication of diagonal elements, and the + specified method is ignored. + + If it is set to ``'domain-ge'``, then Gaussian elimination method will + be used via using DomainMatrix. + + If it is set to ``'bareiss'``, Bareiss' fraction-free algorithm will + be used. + + If it is set to ``'berkowitz'``, Berkowitz' algorithm will be used. + + If it is set to ``'bird'``, Bird's algorithm will be used [1]_. + + If it is set to ``'laplace'``, Laplace's algorithm will be used. + + Otherwise, if it is set to ``'lu'``, LU decomposition will be used. + + .. note:: + For backward compatibility, legacy keys like "bareis" and + "det_lu" can still be used to indicate the corresponding + methods. + And the keys are also case-insensitive for now. However, it is + suggested to use the precise keys for specifying the method. + + iszerofunc : FunctionType or None, optional + If it is set to ``None``, it will be defaulted to ``_iszero`` if the + method is set to ``'bareiss'``, and ``_is_zero_after_expand_mul`` if + the method is set to ``'lu'``. + + It can also accept any user-specified zero testing function, if it + is formatted as a function which accepts a single symbolic argument + and returns ``True`` if it is tested as zero and ``False`` if it + tested as non-zero, and also ``None`` if it is undecidable. + + Returns + ======= + + det : Basic + Result of determinant. + + Raises + ====== + + ValueError + If unrecognized keys are given for ``method`` or ``iszerofunc``. + + NonSquareMatrixError + If attempted to calculate determinant from a non-square matrix. + + Examples + ======== + + >>> from sympy import Matrix, eye, det + >>> I3 = eye(3) + >>> det(I3) + 1 + >>> M = Matrix([[1, 2], [3, 4]]) + >>> det(M) + -2 + >>> det(M) == M.det() + True + >>> M.det(method="domain-ge") + -2 + + References + ========== + + .. [1] Bird, R. S. (2011). A simple division-free algorithm for computing + determinants. Inf. Process. Lett., 111(21), 1072-1074. doi: + 10.1016/j.ipl.2011.08.006 + """ + + # sanitize `method` + method = method.lower() + + if method == "bareis": + method = "bareiss" + elif method == "det_lu": + method = "lu" + + if method not in ("bareiss", "berkowitz", "lu", "domain-ge", "bird", + "laplace"): + raise ValueError("Determinant method '%s' unrecognized" % method) + + if iszerofunc is None: + if method == "bareiss": + iszerofunc = _is_zero_after_expand_mul + elif method == "lu": + iszerofunc = _iszero + + elif not isinstance(iszerofunc, FunctionType): + raise ValueError("Zero testing method '%s' unrecognized" % iszerofunc) + + n = M.rows + + if n == M.cols: # square check is done in individual method functions + if n == 0: + return M.one + elif n == 1: + return M[0, 0] + elif n == 2: + m = M[0, 0] * M[1, 1] - M[0, 1] * M[1, 0] + return _get_intermediate_simp(_dotprodsimp)(m) + elif n == 3: + m = (M[0, 0] * M[1, 1] * M[2, 2] + + M[0, 1] * M[1, 2] * M[2, 0] + + M[0, 2] * M[1, 0] * M[2, 1] + - M[0, 2] * M[1, 1] * M[2, 0] + - M[0, 0] * M[1, 2] * M[2, 1] + - M[0, 1] * M[1, 0] * M[2, 2]) + return _get_intermediate_simp(_dotprodsimp)(m) + + dets = [] + for b in M.strongly_connected_components(): + if method == "domain-ge": # uses DomainMatrix to evaluate determinant + det = _det_DOM(M[b, b]) + elif method == "bareiss": + det = M[b, b]._eval_det_bareiss(iszerofunc=iszerofunc) + elif method == "berkowitz": + det = M[b, b]._eval_det_berkowitz() + elif method == "lu": + det = M[b, b]._eval_det_lu(iszerofunc=iszerofunc) + elif method == "bird": + det = M[b, b]._eval_det_bird() + elif method == "laplace": + det = M[b, b]._eval_det_laplace() + dets.append(det) + return Mul(*dets) + + +# This functions is a candidate for caching if it gets implemented for matrices. +def _det_bareiss(M, iszerofunc=_is_zero_after_expand_mul): + """Compute matrix determinant using Bareiss' fraction-free + algorithm which is an extension of the well known Gaussian + elimination method. This approach is best suited for dense + symbolic matrices and will result in a determinant with + minimal number of fractions. It means that less term + rewriting is needed on resulting formulae. + + Parameters + ========== + + iszerofunc : function, optional + The function to use to determine zeros when doing an LU decomposition. + Defaults to ``lambda x: x.is_zero``. + + TODO: Implement algorithm for sparse matrices (SFF), + http://www.eecis.udel.edu/~saunders/papers/sffge/it5.ps. + """ + + # Recursively implemented Bareiss' algorithm as per Deanna Richelle Leggett's + # thesis http://www.math.usm.edu/perry/Research/Thesis_DRL.pdf + def bareiss(mat, cumm=1): + if mat.rows == 0: + return mat.one + elif mat.rows == 1: + return mat[0, 0] + + # find a pivot and extract the remaining matrix + # With the default iszerofunc, _find_reasonable_pivot slows down + # the computation by the factor of 2.5 in one test. + # Relevant issues: #10279 and #13877. + pivot_pos, pivot_val, _, _ = _find_reasonable_pivot(mat[:, 0], iszerofunc=iszerofunc) + if pivot_pos is None: + return mat.zero + + # if we have a valid pivot, we'll do a "row swap", so keep the + # sign of the det + sign = (-1) ** (pivot_pos % 2) + + # we want every row but the pivot row and every column + rows = [i for i in range(mat.rows) if i != pivot_pos] + cols = list(range(mat.cols)) + tmp_mat = mat.extract(rows, cols) + + def entry(i, j): + ret = (pivot_val*tmp_mat[i, j + 1] - mat[pivot_pos, j + 1]*tmp_mat[i, 0]) / cumm + if _get_intermediate_simp_bool(True): + return _dotprodsimp(ret) + elif not ret.is_Atom: + return cancel(ret) + return ret + + return sign*bareiss(M._new(mat.rows - 1, mat.cols - 1, entry), pivot_val) + + if not M.is_square: + raise NonSquareMatrixError() + + if M.rows == 0: + return M.one + # sympy/matrices/tests/test_matrices.py contains a test that + # suggests that the determinant of a 0 x 0 matrix is one, by + # convention. + + return bareiss(M) + + +def _det_berkowitz(M): + """ Use the Berkowitz algorithm to compute the determinant.""" + + if not M.is_square: + raise NonSquareMatrixError() + + if M.rows == 0: + return M.one + # sympy/matrices/tests/test_matrices.py contains a test that + # suggests that the determinant of a 0 x 0 matrix is one, by + # convention. + + berk_vector = _berkowitz_vector(M) + return (-1)**(len(berk_vector) - 1) * berk_vector[-1] + + +# This functions is a candidate for caching if it gets implemented for matrices. +def _det_LU(M, iszerofunc=_iszero, simpfunc=None): + """ Computes the determinant of a matrix from its LU decomposition. + This function uses the LU decomposition computed by + LUDecomposition_Simple(). + + The keyword arguments iszerofunc and simpfunc are passed to + LUDecomposition_Simple(). + iszerofunc is a callable that returns a boolean indicating if its + input is zero, or None if it cannot make the determination. + simpfunc is a callable that simplifies its input. + The default is simpfunc=None, which indicate that the pivot search + algorithm should not attempt to simplify any candidate pivots. + If simpfunc fails to simplify its input, then it must return its input + instead of a copy. + + Parameters + ========== + + iszerofunc : function, optional + The function to use to determine zeros when doing an LU decomposition. + Defaults to ``lambda x: x.is_zero``. + + simpfunc : function, optional + The simplification function to use when looking for zeros for pivots. + """ + + if not M.is_square: + raise NonSquareMatrixError() + + if M.rows == 0: + return M.one + # sympy/matrices/tests/test_matrices.py contains a test that + # suggests that the determinant of a 0 x 0 matrix is one, by + # convention. + + lu, row_swaps = M.LUdecomposition_Simple(iszerofunc=iszerofunc, + simpfunc=simpfunc) + # P*A = L*U => det(A) = det(L)*det(U)/det(P) = det(P)*det(U). + # Lower triangular factor L encoded in lu has unit diagonal => det(L) = 1. + # P is a permutation matrix => det(P) in {-1, 1} => 1/det(P) = det(P). + # LUdecomposition_Simple() returns a list of row exchange index pairs, rather + # than a permutation matrix, but det(P) = (-1)**len(row_swaps). + + # Avoid forming the potentially time consuming product of U's diagonal entries + # if the product is zero. + # Bottom right entry of U is 0 => det(A) = 0. + # It may be impossible to determine if this entry of U is zero when it is symbolic. + if iszerofunc(lu[lu.rows-1, lu.rows-1]): + return M.zero + + # Compute det(P) + det = -M.one if len(row_swaps)%2 else M.one + + # Compute det(U) by calculating the product of U's diagonal entries. + # The upper triangular portion of lu is the upper triangular portion of the + # U factor in the LU decomposition. + for k in range(lu.rows): + det *= lu[k, k] + + # return det(P)*det(U) + return det + + +@cacheit +def __det_laplace(M): + """Compute the determinant of a matrix using Laplace expansion. + + This is a recursive function, and it should not be called directly. + Use _det_laplace() instead. The reason for splitting this function + into two is to allow caching of determinants of submatrices. While + one could also define this function inside _det_laplace(), that + would remove the advantage of using caching in Cramer Solve. + """ + n = M.shape[0] + if n == 1: + return M[0] + elif n == 2: + return M[0, 0] * M[1, 1] - M[0, 1] * M[1, 0] + else: + return sum((-1) ** i * M[0, i] * + __det_laplace(M.minor_submatrix(0, i)) for i in range(n)) + + +def _det_laplace(M): + """Compute the determinant of a matrix using Laplace expansion. + + While Laplace expansion is not the most efficient method of computing + a determinant, it is a simple one, and it has the advantage of + being division free. To improve efficiency, this function uses + caching to avoid recomputing determinants of submatrices. + """ + if not M.is_square: + raise NonSquareMatrixError() + if M.shape[0] == 0: + return M.one + # sympy/matrices/tests/test_matrices.py contains a test that + # suggests that the determinant of a 0 x 0 matrix is one, by + # convention. + return __det_laplace(M.as_immutable()) + + +def _det_bird(M): + r"""Compute the determinant of a matrix using Bird's algorithm. + + Bird's algorithm is a simple division-free algorithm for computing, which + is of lower order than the Laplace's algorithm. It is described in [1]_. + + References + ========== + + .. [1] Bird, R. S. (2011). A simple division-free algorithm for computing + determinants. Inf. Process. Lett., 111(21), 1072-1074. doi: + 10.1016/j.ipl.2011.08.006 + """ + def mu(X): + n = X.shape[0] + zero = X.domain.zero + + total = zero + diag_sums = [zero] + for i in reversed(range(1, n)): + total -= X[i][i] + diag_sums.append(total) + diag_sums = diag_sums[::-1] + + elems = [[zero] * i + [diag_sums[i]] + X_i[i + 1:] for i, X_i in + enumerate(X)] + return DDM(elems, X.shape, X.domain) + + Mddm = M._rep.to_ddm() + n = M.shape[0] + if n == 0: + return M.one + # sympy/matrices/tests/test_matrices.py contains a test that + # suggests that the determinant of a 0 x 0 matrix is one, by + # convention. + Fn1 = Mddm + for _ in range(n - 1): + Fn1 = mu(Fn1).matmul(Mddm) + detA = Fn1[0][0] + if n % 2 == 0: + detA = -detA + + return Mddm.domain.to_sympy(detA) + + +def _minor(M, i, j, method="berkowitz"): + """Return the (i,j) minor of ``M``. That is, + return the determinant of the matrix obtained by deleting + the `i`th row and `j`th column from ``M``. + + Parameters + ========== + + i, j : int + The row and column to exclude to obtain the submatrix. + + method : string, optional + Method to use to find the determinant of the submatrix, can be + "bareiss", "berkowitz", "bird", "laplace" or "lu". + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) + >>> M.minor(1, 1) + -12 + + See Also + ======== + + minor_submatrix + cofactor + det + """ + + if not M.is_square: + raise NonSquareMatrixError() + + return M.minor_submatrix(i, j).det(method=method) + + +def _minor_submatrix(M, i, j): + """Return the submatrix obtained by removing the `i`th row + and `j`th column from ``M`` (works with Pythonic negative indices). + + Parameters + ========== + + i, j : int + The row and column to exclude to obtain the submatrix. + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) + >>> M.minor_submatrix(1, 1) + Matrix([ + [1, 3], + [7, 9]]) + + See Also + ======== + + minor + cofactor + """ + + if i < 0: + i += M.rows + if j < 0: + j += M.cols + + if not 0 <= i < M.rows or not 0 <= j < M.cols: + raise ValueError("`i` and `j` must satisfy 0 <= i < ``M.rows`` " + "(%d)" % M.rows + "and 0 <= j < ``M.cols`` (%d)." % M.cols) + + rows = [a for a in range(M.rows) if a != i] + cols = [a for a in range(M.cols) if a != j] + + return M.extract(rows, cols) diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/eigen.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/eigen.py new file mode 100644 index 0000000000000000000000000000000000000000..87b2418efcece1c0b158ec56995bb011286feb3c --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/eigen.py @@ -0,0 +1,1346 @@ +from types import FunctionType +from collections import Counter + +from mpmath import mp, workprec +from mpmath.libmp.libmpf import prec_to_dps + +from sympy.core.sorting import default_sort_key +from sympy.core.evalf import DEFAULT_MAXPREC, PrecisionExhausted +from sympy.core.logic import fuzzy_and, fuzzy_or +from sympy.core.numbers import Float +from sympy.core.sympify import _sympify +from sympy.functions.elementary.miscellaneous import sqrt +from sympy.polys import roots, CRootOf, ZZ, QQ, EX +from sympy.polys.matrices import DomainMatrix +from sympy.polys.matrices.eigen import dom_eigenvects, dom_eigenvects_to_sympy +from sympy.polys.polytools import gcd + +from .exceptions import MatrixError, NonSquareMatrixError +from .determinant import _find_reasonable_pivot + +from .utilities import _iszero, _simplify + + +__doctest_requires__ = { + ('_is_indefinite', + '_is_negative_definite', + '_is_negative_semidefinite', + '_is_positive_definite', + '_is_positive_semidefinite'): ['matplotlib'], +} + + +def _eigenvals_eigenvects_mpmath(M): + norm2 = lambda v: mp.sqrt(sum(i**2 for i in v)) + + v1 = None + prec = max(x._prec for x in M.atoms(Float)) + eps = 2**-prec + + while prec < DEFAULT_MAXPREC: + with workprec(prec): + A = mp.matrix(M.evalf(n=prec_to_dps(prec))) + E, ER = mp.eig(A) + v2 = norm2([i for e in E for i in (mp.re(e), mp.im(e))]) + if v1 is not None and mp.fabs(v1 - v2) < eps: + return E, ER + v1 = v2 + prec *= 2 + + # we get here because the next step would have taken us + # past MAXPREC or because we never took a step; in case + # of the latter, we refuse to send back a solution since + # it would not have been verified; we also resist taking + # a small step to arrive exactly at MAXPREC since then + # the two calculations might be artificially close. + raise PrecisionExhausted + + +def _eigenvals_mpmath(M, multiple=False): + """Compute eigenvalues using mpmath""" + E, _ = _eigenvals_eigenvects_mpmath(M) + result = [_sympify(x) for x in E] + if multiple: + return result + return dict(Counter(result)) + + +def _eigenvects_mpmath(M): + E, ER = _eigenvals_eigenvects_mpmath(M) + result = [] + for i in range(M.rows): + eigenval = _sympify(E[i]) + eigenvect = _sympify(ER[:, i]) + result.append((eigenval, 1, [eigenvect])) + + return result + + +# This function is a candidate for caching if it gets implemented for matrices. +def _eigenvals( + M, error_when_incomplete=True, *, simplify=False, multiple=False, + rational=False, **flags): + r"""Compute eigenvalues of the matrix. + + Parameters + ========== + + error_when_incomplete : bool, optional + If it is set to ``True``, it will raise an error if not all + eigenvalues are computed. This is caused by ``roots`` not returning + a full list of eigenvalues. + + simplify : bool or function, optional + If it is set to ``True``, it attempts to return the most + simplified form of expressions returned by applying default + simplification method in every routine. + + If it is set to ``False``, it will skip simplification in this + particular routine to save computation resources. + + If a function is passed to, it will attempt to apply + the particular function as simplification method. + + rational : bool, optional + If it is set to ``True``, every floating point numbers would be + replaced with rationals before computation. It can solve some + issues of ``roots`` routine not working well with floats. + + multiple : bool, optional + If it is set to ``True``, the result will be in the form of a + list. + + If it is set to ``False``, the result will be in the form of a + dictionary. + + Returns + ======= + + eigs : list or dict + Eigenvalues of a matrix. The return format would be specified by + the key ``multiple``. + + Raises + ====== + + MatrixError + If not enough roots had got computed. + + NonSquareMatrixError + If attempted to compute eigenvalues from a non-square matrix. + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix(3, 3, [0, 1, 1, 1, 0, 0, 1, 1, 1]) + >>> M.eigenvals() + {-1: 1, 0: 1, 2: 1} + + See Also + ======== + + MatrixBase.charpoly + eigenvects + + Notes + ===== + + Eigenvalues of a matrix $A$ can be computed by solving a matrix + equation $\det(A - \lambda I) = 0$ + + It's not always possible to return radical solutions for + eigenvalues for matrices larger than $4, 4$ shape due to + Abel-Ruffini theorem. + + If there is no radical solution is found for the eigenvalue, + it may return eigenvalues in the form of + :class:`sympy.polys.rootoftools.ComplexRootOf`. + """ + if not M: + if multiple: + return [] + return {} + + if not M.is_square: + raise NonSquareMatrixError("{} must be a square matrix.".format(M)) + + if M._rep.domain not in (ZZ, QQ): + # Skip this check for ZZ/QQ because it can be slow + if all(x.is_number for x in M) and M.has(Float): + return _eigenvals_mpmath(M, multiple=multiple) + + if rational: + from sympy.simplify import nsimplify + M = M.applyfunc( + lambda x: nsimplify(x, rational=True) if x.has(Float) else x) + + if multiple: + return _eigenvals_list( + M, error_when_incomplete=error_when_incomplete, simplify=simplify, + **flags) + return _eigenvals_dict( + M, error_when_incomplete=error_when_incomplete, simplify=simplify, + **flags) + + +eigenvals_error_message = \ +"It is not always possible to express the eigenvalues of a matrix " + \ +"of size 5x5 or higher in radicals. " + \ +"We have CRootOf, but domains other than the rationals are not " + \ +"currently supported. " + \ +"If there are no symbols in the matrix, " + \ +"it should still be possible to compute numeric approximations " + \ +"of the eigenvalues using " + \ +"M.evalf().eigenvals() or M.charpoly().nroots()." + + +def _eigenvals_list( + M, error_when_incomplete=True, simplify=False, **flags): + iblocks = M.strongly_connected_components() + all_eigs = [] + is_dom = M._rep.domain in (ZZ, QQ) + for b in iblocks: + + # Fast path for a 1x1 block: + if is_dom and len(b) == 1: + index = b[0] + val = M[index, index] + all_eigs.append(val) + continue + + block = M[b, b] + + if isinstance(simplify, FunctionType): + charpoly = block.charpoly(simplify=simplify) + else: + charpoly = block.charpoly() + + eigs = roots(charpoly, multiple=True, **flags) + + if len(eigs) != block.rows: + try: + eigs = charpoly.all_roots(multiple=True) + except NotImplementedError: + if error_when_incomplete: + raise MatrixError(eigenvals_error_message) + else: + eigs = [] + + all_eigs += eigs + + if not simplify: + return all_eigs + if not isinstance(simplify, FunctionType): + simplify = _simplify + return [simplify(value) for value in all_eigs] + + +def _eigenvals_dict( + M, error_when_incomplete=True, simplify=False, **flags): + iblocks = M.strongly_connected_components() + all_eigs = {} + is_dom = M._rep.domain in (ZZ, QQ) + for b in iblocks: + + # Fast path for a 1x1 block: + if is_dom and len(b) == 1: + index = b[0] + val = M[index, index] + all_eigs[val] = all_eigs.get(val, 0) + 1 + continue + + block = M[b, b] + + if isinstance(simplify, FunctionType): + charpoly = block.charpoly(simplify=simplify) + else: + charpoly = block.charpoly() + + eigs = roots(charpoly, multiple=False, **flags) + + if sum(eigs.values()) != block.rows: + try: + eigs = dict(charpoly.all_roots(multiple=False)) + except NotImplementedError: + if error_when_incomplete: + raise MatrixError(eigenvals_error_message) + else: + eigs = {} + + for k, v in eigs.items(): + if k in all_eigs: + all_eigs[k] += v + else: + all_eigs[k] = v + + if not simplify: + return all_eigs + if not isinstance(simplify, FunctionType): + simplify = _simplify + return {simplify(key): value for key, value in all_eigs.items()} + + +def _eigenspace(M, eigenval, iszerofunc=_iszero, simplify=False): + """Get a basis for the eigenspace for a particular eigenvalue""" + m = M - M.eye(M.rows) * eigenval + ret = m.nullspace(iszerofunc=iszerofunc) + + # The nullspace for a real eigenvalue should be non-trivial. + # If we didn't find an eigenvector, try once more a little harder + if len(ret) == 0 and simplify: + ret = m.nullspace(iszerofunc=iszerofunc, simplify=True) + if len(ret) == 0: + raise NotImplementedError( + "Can't evaluate eigenvector for eigenvalue {}".format(eigenval)) + return ret + + +def _eigenvects_DOM(M, **kwargs): + DOM = DomainMatrix.from_Matrix(M, field=True, extension=True) + DOM = DOM.to_dense() + + if DOM.domain != EX: + rational, algebraic = dom_eigenvects(DOM) + eigenvects = dom_eigenvects_to_sympy( + rational, algebraic, M.__class__, **kwargs) + eigenvects = sorted(eigenvects, key=lambda x: default_sort_key(x[0])) + + return eigenvects + return None + + +def _eigenvects_sympy(M, iszerofunc, simplify=True, **flags): + eigenvals = M.eigenvals(rational=False, **flags) + + # Make sure that we have all roots in radical form + for x in eigenvals: + if x.has(CRootOf): + raise MatrixError( + "Eigenvector computation is not implemented if the matrix have " + "eigenvalues in CRootOf form") + + eigenvals = sorted(eigenvals.items(), key=default_sort_key) + ret = [] + for val, mult in eigenvals: + vects = _eigenspace(M, val, iszerofunc=iszerofunc, simplify=simplify) + ret.append((val, mult, vects)) + return ret + + +# This functions is a candidate for caching if it gets implemented for matrices. +def _eigenvects(M, error_when_incomplete=True, iszerofunc=_iszero, *, chop=False, **flags): + """Compute eigenvectors of the matrix. + + Parameters + ========== + + error_when_incomplete : bool, optional + Raise an error when not all eigenvalues are computed. This is + caused by ``roots`` not returning a full list of eigenvalues. + + iszerofunc : function, optional + Specifies a zero testing function to be used in ``rref``. + + Default value is ``_iszero``, which uses SymPy's naive and fast + default assumption handler. + + It can also accept any user-specified zero testing function, if it + is formatted as a function which accepts a single symbolic argument + and returns ``True`` if it is tested as zero and ``False`` if it + is tested as non-zero, and ``None`` if it is undecidable. + + simplify : bool or function, optional + If ``True``, ``as_content_primitive()`` will be used to tidy up + normalization artifacts. + + It will also be used by the ``nullspace`` routine. + + chop : bool or positive number, optional + If the matrix contains any Floats, they will be changed to Rationals + for computation purposes, but the answers will be returned after + being evaluated with evalf. The ``chop`` flag is passed to ``evalf``. + When ``chop=True`` a default precision will be used; a number will + be interpreted as the desired level of precision. + + Returns + ======= + + ret : [(eigenval, multiplicity, eigenspace), ...] + A ragged list containing tuples of data obtained by ``eigenvals`` + and ``nullspace``. + + ``eigenspace`` is a list containing the ``eigenvector`` for each + eigenvalue. + + ``eigenvector`` is a vector in the form of a ``Matrix``. e.g. + a vector of length 3 is returned as ``Matrix([a_1, a_2, a_3])``. + + Raises + ====== + + NotImplementedError + If failed to compute nullspace. + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix(3, 3, [0, 1, 1, 1, 0, 0, 1, 1, 1]) + >>> M.eigenvects() + [(-1, 1, [Matrix([ + [-1], + [ 1], + [ 0]])]), (0, 1, [Matrix([ + [ 0], + [-1], + [ 1]])]), (2, 1, [Matrix([ + [2/3], + [1/3], + [ 1]])])] + + See Also + ======== + + eigenvals + MatrixBase.nullspace + """ + simplify = flags.get('simplify', True) + primitive = flags.get('simplify', False) + flags.pop('simplify', None) # remove this if it's there + flags.pop('multiple', None) # remove this if it's there + + if not isinstance(simplify, FunctionType): + simpfunc = _simplify if simplify else lambda x: x + + has_floats = M.has(Float) + if has_floats: + if all(x.is_number for x in M): + return _eigenvects_mpmath(M) + from sympy.simplify import nsimplify + M = M.applyfunc(lambda x: nsimplify(x, rational=True)) + + ret = _eigenvects_DOM(M) + if ret is None: + ret = _eigenvects_sympy(M, iszerofunc, simplify=simplify, **flags) + + if primitive: + # if the primitive flag is set, get rid of any common + # integer denominators + def denom_clean(l): + return [(v / gcd(list(v))).applyfunc(simpfunc) for v in l] + + ret = [(val, mult, denom_clean(es)) for val, mult, es in ret] + + if has_floats: + # if we had floats to start with, turn the eigenvectors to floats + ret = [(val.evalf(chop=chop), mult, [v.evalf(chop=chop) for v in es]) + for val, mult, es in ret] + + return ret + + +def _is_diagonalizable_with_eigen(M, reals_only=False): + """See _is_diagonalizable. This function returns the bool along with the + eigenvectors to avoid calculating them again in functions like + ``diagonalize``.""" + + if not M.is_square: + return False, [] + + eigenvecs = M.eigenvects(simplify=True) + + for val, mult, basis in eigenvecs: + if reals_only and not val.is_real: # if we have a complex eigenvalue + return False, eigenvecs + + if mult != len(basis): # if the geometric multiplicity doesn't equal the algebraic + return False, eigenvecs + + return True, eigenvecs + +def _is_diagonalizable(M, reals_only=False, **kwargs): + """Returns ``True`` if a matrix is diagonalizable. + + Parameters + ========== + + reals_only : bool, optional + If ``True``, it tests whether the matrix can be diagonalized + to contain only real numbers on the diagonal. + + + If ``False``, it tests whether the matrix can be diagonalized + at all, even with numbers that may not be real. + + Examples + ======== + + Example of a diagonalizable matrix: + + >>> from sympy import Matrix + >>> M = Matrix([[1, 2, 0], [0, 3, 0], [2, -4, 2]]) + >>> M.is_diagonalizable() + True + + Example of a non-diagonalizable matrix: + + >>> M = Matrix([[0, 1], [0, 0]]) + >>> M.is_diagonalizable() + False + + Example of a matrix that is diagonalized in terms of non-real entries: + + >>> M = Matrix([[0, 1], [-1, 0]]) + >>> M.is_diagonalizable(reals_only=False) + True + >>> M.is_diagonalizable(reals_only=True) + False + + See Also + ======== + + sympy.matrices.matrixbase.MatrixBase.is_diagonal + diagonalize + """ + if not M.is_square: + return False + + if all(e.is_real for e in M) and M.is_symmetric(): + return True + + if all(e.is_complex for e in M) and M.is_hermitian: + return True + + return _is_diagonalizable_with_eigen(M, reals_only=reals_only)[0] + + +#G&VL, Matrix Computations, Algo 5.4.2 +def _householder_vector(x): + if not x.cols == 1: + raise ValueError("Input must be a column matrix") + v = x.copy() + v_plus = x.copy() + v_minus = x.copy() + q = x[0, 0] / abs(x[0, 0]) + norm_x = x.norm() + v_plus[0, 0] = x[0, 0] + q * norm_x + v_minus[0, 0] = x[0, 0] - q * norm_x + if x[1:, 0].norm() == 0: + bet = 0 + v[0, 0] = 1 + else: + if v_plus.norm() <= v_minus.norm(): + v = v_plus + else: + v = v_minus + v = v / v[0] + bet = 2 / (v.norm() ** 2) + return v, bet + + +def _bidiagonal_decmp_hholder(M): + m = M.rows + n = M.cols + A = M.as_mutable() + U, V = A.eye(m), A.eye(n) + for i in range(min(m, n)): + v, bet = _householder_vector(A[i:, i]) + hh_mat = A.eye(m - i) - bet * v * v.H + A[i:, i:] = hh_mat * A[i:, i:] + temp = A.eye(m) + temp[i:, i:] = hh_mat + U = U * temp + if i + 1 <= n - 2: + v, bet = _householder_vector(A[i, i+1:].T) + hh_mat = A.eye(n - i - 1) - bet * v * v.H + A[i:, i+1:] = A[i:, i+1:] * hh_mat + temp = A.eye(n) + temp[i+1:, i+1:] = hh_mat + V = temp * V + return U, A, V + + +def _eval_bidiag_hholder(M): + m = M.rows + n = M.cols + A = M.as_mutable() + for i in range(min(m, n)): + v, bet = _householder_vector(A[i:, i]) + hh_mat = A.eye(m-i) - bet * v * v.H + A[i:, i:] = hh_mat * A[i:, i:] + if i + 1 <= n - 2: + v, bet = _householder_vector(A[i, i+1:].T) + hh_mat = A.eye(n - i - 1) - bet * v * v.H + A[i:, i+1:] = A[i:, i+1:] * hh_mat + return A + + +def _bidiagonal_decomposition(M, upper=True): + """ + Returns $(U,B,V.H)$ for + + $$A = UBV^{H}$$ + + where $A$ is the input matrix, and $B$ is its Bidiagonalized form + + Note: Bidiagonal Computation can hang for symbolic matrices. + + Parameters + ========== + + upper : bool. Whether to do upper bidiagnalization or lower. + True for upper and False for lower. + + References + ========== + + .. [1] Algorithm 5.4.2, Matrix computations by Golub and Van Loan, 4th edition + .. [2] Complex Matrix Bidiagonalization, https://github.com/vslobody/Householder-Bidiagonalization + + """ + + if not isinstance(upper, bool): + raise ValueError("upper must be a boolean") + + if upper: + return _bidiagonal_decmp_hholder(M) + + X = _bidiagonal_decmp_hholder(M.H) + return X[2].H, X[1].H, X[0].H + + +def _bidiagonalize(M, upper=True): + """ + Returns $B$, the Bidiagonalized form of the input matrix. + + Note: Bidiagonal Computation can hang for symbolic matrices. + + Parameters + ========== + + upper : bool. Whether to do upper bidiagnalization or lower. + True for upper and False for lower. + + References + ========== + + .. [1] Algorithm 5.4.2, Matrix computations by Golub and Van Loan, 4th edition + .. [2] Complex Matrix Bidiagonalization : https://github.com/vslobody/Householder-Bidiagonalization + + """ + + if not isinstance(upper, bool): + raise ValueError("upper must be a boolean") + + if upper: + return _eval_bidiag_hholder(M) + return _eval_bidiag_hholder(M.H).H + + +def _diagonalize(M, reals_only=False, sort=False, normalize=False): + """ + Return (P, D), where D is diagonal and + + D = P^-1 * M * P + + where M is current matrix. + + Parameters + ========== + + reals_only : bool. Whether to throw an error if complex numbers are need + to diagonalize. (Default: False) + + sort : bool. Sort the eigenvalues along the diagonal. (Default: False) + + normalize : bool. If True, normalize the columns of P. (Default: False) + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix(3, 3, [1, 2, 0, 0, 3, 0, 2, -4, 2]) + >>> M + Matrix([ + [1, 2, 0], + [0, 3, 0], + [2, -4, 2]]) + >>> (P, D) = M.diagonalize() + >>> D + Matrix([ + [1, 0, 0], + [0, 2, 0], + [0, 0, 3]]) + >>> P + Matrix([ + [-1, 0, -1], + [ 0, 0, -1], + [ 2, 1, 2]]) + >>> P.inv() * M * P + Matrix([ + [1, 0, 0], + [0, 2, 0], + [0, 0, 3]]) + + See Also + ======== + + sympy.matrices.matrixbase.MatrixBase.is_diagonal + is_diagonalizable + """ + + if not M.is_square: + raise NonSquareMatrixError() + + is_diagonalizable, eigenvecs = _is_diagonalizable_with_eigen(M, + reals_only=reals_only) + + if not is_diagonalizable: + raise MatrixError("Matrix is not diagonalizable") + + if sort: + eigenvecs = sorted(eigenvecs, key=default_sort_key) + + p_cols, diag = [], [] + + for val, mult, basis in eigenvecs: + diag += [val] * mult + p_cols += basis + + if normalize: + p_cols = [v / v.norm() for v in p_cols] + + return M.hstack(*p_cols), M.diag(*diag) + + +def _fuzzy_positive_definite(M): + positive_diagonals = M._has_positive_diagonals() + if positive_diagonals is False: + return False + + if positive_diagonals and M.is_strongly_diagonally_dominant: + return True + + return None + + +def _fuzzy_positive_semidefinite(M): + nonnegative_diagonals = M._has_nonnegative_diagonals() + if nonnegative_diagonals is False: + return False + + if nonnegative_diagonals and M.is_weakly_diagonally_dominant: + return True + + return None + + +def _is_positive_definite(M): + if not M.is_hermitian: + if not M.is_square: + return False + M = M + M.H + + fuzzy = _fuzzy_positive_definite(M) + if fuzzy is not None: + return fuzzy + + return _is_positive_definite_GE(M) + + +def _is_positive_semidefinite(M): + if not M.is_hermitian: + if not M.is_square: + return False + M = M + M.H + + fuzzy = _fuzzy_positive_semidefinite(M) + if fuzzy is not None: + return fuzzy + + return _is_positive_semidefinite_cholesky(M) + + +def _is_negative_definite(M): + return _is_positive_definite(-M) + + +def _is_negative_semidefinite(M): + return _is_positive_semidefinite(-M) + + +def _is_indefinite(M): + if M.is_hermitian: + eigen = M.eigenvals() + args1 = [x.is_positive for x in eigen.keys()] + any_positive = fuzzy_or(args1) + args2 = [x.is_negative for x in eigen.keys()] + any_negative = fuzzy_or(args2) + + return fuzzy_and([any_positive, any_negative]) + + elif M.is_square: + return (M + M.H).is_indefinite + + return False + + +def _is_positive_definite_GE(M): + """A division-free gaussian elimination method for testing + positive-definiteness.""" + M = M.as_mutable() + size = M.rows + + for i in range(size): + is_positive = M[i, i].is_positive + if is_positive is not True: + return is_positive + for j in range(i+1, size): + M[j, i+1:] = M[i, i] * M[j, i+1:] - M[j, i] * M[i, i+1:] + return True + + +def _is_positive_semidefinite_cholesky(M): + """Uses Cholesky factorization with complete pivoting + + References + ========== + + .. [1] http://eprints.ma.man.ac.uk/1199/1/covered/MIMS_ep2008_116.pdf + + .. [2] https://www.value-at-risk.net/cholesky-factorization/ + """ + M = M.as_mutable() + for k in range(M.rows): + diags = [M[i, i] for i in range(k, M.rows)] + pivot, pivot_val, nonzero, _ = _find_reasonable_pivot(diags) + + if nonzero: + return None + + if pivot is None: + for i in range(k+1, M.rows): + for j in range(k, M.cols): + iszero = M[i, j].is_zero + if iszero is None: + return None + elif iszero is False: + return False + return True + + if M[k, k].is_negative or pivot_val.is_negative: + return False + elif not (M[k, k].is_nonnegative and pivot_val.is_nonnegative): + return None + + if pivot > 0: + M.col_swap(k, k+pivot) + M.row_swap(k, k+pivot) + + M[k, k] = sqrt(M[k, k]) + M[k, k+1:] /= M[k, k] + M[k+1:, k+1:] -= M[k, k+1:].H * M[k, k+1:] + + return M[-1, -1].is_nonnegative + + +_doc_positive_definite = \ + r"""Finds out the definiteness of a matrix. + + Explanation + =========== + + A square real matrix $A$ is: + + - A positive definite matrix if $x^T A x > 0$ + for all non-zero real vectors $x$. + - A positive semidefinite matrix if $x^T A x \geq 0$ + for all non-zero real vectors $x$. + - A negative definite matrix if $x^T A x < 0$ + for all non-zero real vectors $x$. + - A negative semidefinite matrix if $x^T A x \leq 0$ + for all non-zero real vectors $x$. + - An indefinite matrix if there exists non-zero real vectors + $x, y$ with $x^T A x > 0 > y^T A y$. + + A square complex matrix $A$ is: + + - A positive definite matrix if $\text{re}(x^H A x) > 0$ + for all non-zero complex vectors $x$. + - A positive semidefinite matrix if $\text{re}(x^H A x) \geq 0$ + for all non-zero complex vectors $x$. + - A negative definite matrix if $\text{re}(x^H A x) < 0$ + for all non-zero complex vectors $x$. + - A negative semidefinite matrix if $\text{re}(x^H A x) \leq 0$ + for all non-zero complex vectors $x$. + - An indefinite matrix if there exists non-zero complex vectors + $x, y$ with $\text{re}(x^H A x) > 0 > \text{re}(y^H A y)$. + + A matrix need not be symmetric or hermitian to be positive definite. + + - A real non-symmetric matrix is positive definite if and only if + $\frac{A + A^T}{2}$ is positive definite. + - A complex non-hermitian matrix is positive definite if and only if + $\frac{A + A^H}{2}$ is positive definite. + + And this extension can apply for all the definitions above. + + However, for complex cases, you can restrict the definition of + $\text{re}(x^H A x) > 0$ to $x^H A x > 0$ and require the matrix + to be hermitian. + But we do not present this restriction for computation because you + can check ``M.is_hermitian`` independently with this and use + the same procedure. + + Examples + ======== + + An example of symmetric positive definite matrix: + + .. plot:: + :context: reset + :format: doctest + :include-source: True + + >>> from sympy import Matrix, symbols + >>> from sympy.plotting import plot3d + >>> a, b = symbols('a b') + >>> x = Matrix([a, b]) + + >>> A = Matrix([[1, 0], [0, 1]]) + >>> A.is_positive_definite + True + >>> A.is_positive_semidefinite + True + + >>> p = plot3d((x.T*A*x)[0, 0], (a, -1, 1), (b, -1, 1)) + + An example of symmetric positive semidefinite matrix: + + .. plot:: + :context: close-figs + :format: doctest + :include-source: True + + >>> A = Matrix([[1, -1], [-1, 1]]) + >>> A.is_positive_definite + False + >>> A.is_positive_semidefinite + True + + >>> p = plot3d((x.T*A*x)[0, 0], (a, -1, 1), (b, -1, 1)) + + An example of symmetric negative definite matrix: + + .. plot:: + :context: close-figs + :format: doctest + :include-source: True + + >>> A = Matrix([[-1, 0], [0, -1]]) + >>> A.is_negative_definite + True + >>> A.is_negative_semidefinite + True + >>> A.is_indefinite + False + + >>> p = plot3d((x.T*A*x)[0, 0], (a, -1, 1), (b, -1, 1)) + + An example of symmetric indefinite matrix: + + .. plot:: + :context: close-figs + :format: doctest + :include-source: True + + >>> A = Matrix([[1, 2], [2, -1]]) + >>> A.is_indefinite + True + + >>> p = plot3d((x.T*A*x)[0, 0], (a, -1, 1), (b, -1, 1)) + + An example of non-symmetric positive definite matrix. + + .. plot:: + :context: close-figs + :format: doctest + :include-source: True + + >>> A = Matrix([[1, 2], [-2, 1]]) + >>> A.is_positive_definite + True + >>> A.is_positive_semidefinite + True + + >>> p = plot3d((x.T*A*x)[0, 0], (a, -1, 1), (b, -1, 1)) + + Notes + ===== + + Although some people trivialize the definition of positive definite + matrices only for symmetric or hermitian matrices, this restriction + is not correct because it does not classify all instances of + positive definite matrices from the definition $x^T A x > 0$ or + $\text{re}(x^H A x) > 0$. + + For instance, ``Matrix([[1, 2], [-2, 1]])`` presented in + the example above is an example of real positive definite matrix + that is not symmetric. + + However, since the following formula holds true; + + .. math:: + \text{re}(x^H A x) > 0 \iff + \text{re}(x^H \frac{A + A^H}{2} x) > 0 + + We can classify all positive definite matrices that may or may not + be symmetric or hermitian by transforming the matrix to + $\frac{A + A^T}{2}$ or $\frac{A + A^H}{2}$ + (which is guaranteed to be always real symmetric or complex + hermitian) and we can defer most of the studies to symmetric or + hermitian positive definite matrices. + + But it is a different problem for the existence of Cholesky + decomposition. Because even though a non symmetric or a non + hermitian matrix can be positive definite, Cholesky or LDL + decomposition does not exist because the decompositions require the + matrix to be symmetric or hermitian. + + References + ========== + + .. [1] https://en.wikipedia.org/wiki/Definiteness_of_a_matrix#Eigenvalues + + .. [2] https://mathworld.wolfram.com/PositiveDefiniteMatrix.html + + .. [3] Johnson, C. R. "Positive Definite Matrices." Amer. + Math. Monthly 77, 259-264 1970. + """ + +_is_positive_definite.__doc__ = _doc_positive_definite +_is_positive_semidefinite.__doc__ = _doc_positive_definite +_is_negative_definite.__doc__ = _doc_positive_definite +_is_negative_semidefinite.__doc__ = _doc_positive_definite +_is_indefinite.__doc__ = _doc_positive_definite + + +def _jordan_form(M, calc_transform=True, *, chop=False): + """Return $(P, J)$ where $J$ is a Jordan block + matrix and $P$ is a matrix such that $M = P J P^{-1}$ + + Parameters + ========== + + calc_transform : bool + If ``False``, then only $J$ is returned. + + chop : bool + All matrices are converted to exact types when computing + eigenvalues and eigenvectors. As a result, there may be + approximation errors. If ``chop==True``, these errors + will be truncated. + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix([[ 6, 5, -2, -3], [-3, -1, 3, 3], [ 2, 1, -2, -3], [-1, 1, 5, 5]]) + >>> P, J = M.jordan_form() + >>> J + Matrix([ + [2, 1, 0, 0], + [0, 2, 0, 0], + [0, 0, 2, 1], + [0, 0, 0, 2]]) + + See Also + ======== + + jordan_block + """ + + if not M.is_square: + raise NonSquareMatrixError("Only square matrices have Jordan forms") + + mat = M + has_floats = M.has(Float) + + if has_floats: + try: + max_prec = max(term._prec for term in M.values() if isinstance(term, Float)) + except ValueError: + # if no term in the matrix is explicitly a Float calling max() + # will throw a error so setting max_prec to default value of 53 + max_prec = 53 + + # setting minimum max_dps to 15 to prevent loss of precision in + # matrix containing non evaluated expressions + max_dps = max(prec_to_dps(max_prec), 15) + + def restore_floats(*args): + """If ``has_floats`` is `True`, cast all ``args`` as + matrices of floats.""" + + if has_floats: + args = [m.evalf(n=max_dps, chop=chop) for m in args] + if len(args) == 1: + return args[0] + + return args + + # cache calculations for some speedup + mat_cache = {} + + def eig_mat(val, pow): + """Cache computations of ``(M - val*I)**pow`` for quick + retrieval""" + + if (val, pow) in mat_cache: + return mat_cache[(val, pow)] + + if (val, pow - 1) in mat_cache: + mat_cache[(val, pow)] = mat_cache[(val, pow - 1)].multiply( + mat_cache[(val, 1)], dotprodsimp=None) + else: + mat_cache[(val, pow)] = (mat - val*M.eye(M.rows)).pow(pow) + + return mat_cache[(val, pow)] + + # helper functions + def nullity_chain(val, algebraic_multiplicity): + """Calculate the sequence [0, nullity(E), nullity(E**2), ...] + until it is constant where ``E = M - val*I``""" + + # mat.rank() is faster than computing the null space, + # so use the rank-nullity theorem + cols = M.cols + ret = [0] + nullity = cols - eig_mat(val, 1).rank() + i = 2 + + while nullity != ret[-1]: + ret.append(nullity) + + if nullity == algebraic_multiplicity: + break + + nullity = cols - eig_mat(val, i).rank() + i += 1 + + # Due to issues like #7146 and #15872, SymPy sometimes + # gives the wrong rank. In this case, raise an error + # instead of returning an incorrect matrix + if nullity < ret[-1] or nullity > algebraic_multiplicity: + raise MatrixError( + "SymPy had encountered an inconsistent " + "result while computing Jordan block: " + "{}".format(M)) + + return ret + + def blocks_from_nullity_chain(d): + """Return a list of the size of each Jordan block. + If d_n is the nullity of E**n, then the number + of Jordan blocks of size n is + + 2*d_n - d_(n-1) - d_(n+1)""" + + # d[0] is always the number of columns, so skip past it + mid = [2*d[n] - d[n - 1] - d[n + 1] for n in range(1, len(d) - 1)] + # d is assumed to plateau with "d[ len(d) ] == d[-1]", so + # 2*d_n - d_(n-1) - d_(n+1) == d_n - d_(n-1) + end = [d[-1] - d[-2]] if len(d) > 1 else [d[0]] + + return mid + end + + def pick_vec(small_basis, big_basis): + """Picks a vector from big_basis that isn't in + the subspace spanned by small_basis""" + + if len(small_basis) == 0: + return big_basis[0] + + for v in big_basis: + _, pivots = M.hstack(*(small_basis + [v])).echelon_form( + with_pivots=True) + + if pivots[-1] == len(small_basis): + return v + + # roots doesn't like Floats, so replace them with Rationals + if has_floats: + from sympy.simplify import nsimplify + mat = mat.applyfunc(lambda x: nsimplify(x, rational=True)) + + # first calculate the jordan block structure + eigs = mat.eigenvals() + + # Make sure that we have all roots in radical form + for x in eigs: + if x.has(CRootOf): + raise MatrixError( + "Jordan normal form is not implemented if the matrix have " + "eigenvalues in CRootOf form") + + # most matrices have distinct eigenvalues + # and so are diagonalizable. In this case, don't + # do extra work! + if len(eigs.keys()) == mat.cols: + blocks = sorted(eigs.keys(), key=default_sort_key) + jordan_mat = mat.diag(*blocks) + + if not calc_transform: + return restore_floats(jordan_mat) + + jordan_basis = [eig_mat(eig, 1).nullspace()[0] + for eig in blocks] + basis_mat = mat.hstack(*jordan_basis) + + return restore_floats(basis_mat, jordan_mat) + + block_structure = [] + + for eig in sorted(eigs.keys(), key=default_sort_key): + algebraic_multiplicity = eigs[eig] + chain = nullity_chain(eig, algebraic_multiplicity) + block_sizes = blocks_from_nullity_chain(chain) + + # if block_sizes = = [a, b, c, ...], then the number of + # Jordan blocks of size 1 is a, of size 2 is b, etc. + # create an array that has (eig, block_size) with one + # entry for each block + size_nums = [(i+1, num) for i, num in enumerate(block_sizes)] + + # we expect larger Jordan blocks to come earlier + size_nums.reverse() + + block_structure.extend( + [(eig, size) for size, num in size_nums for _ in range(num)]) + + jordan_form_size = sum(size for eig, size in block_structure) + + if jordan_form_size != M.rows: + raise MatrixError( + "SymPy had encountered an inconsistent result while " + "computing Jordan block. : {}".format(M)) + + blocks = (mat.jordan_block(size=size, eigenvalue=eig) for eig, size in block_structure) + jordan_mat = mat.diag(*blocks) + + if not calc_transform: + return restore_floats(jordan_mat) + + # For each generalized eigenspace, calculate a basis. + # We start by looking for a vector in null( (A - eig*I)**n ) + # which isn't in null( (A - eig*I)**(n-1) ) where n is + # the size of the Jordan block + # + # Ideally we'd just loop through block_structure and + # compute each generalized eigenspace. However, this + # causes a lot of unneeded computation. Instead, we + # go through the eigenvalues separately, since we know + # their generalized eigenspaces must have bases that + # are linearly independent. + jordan_basis = [] + + for eig in sorted(eigs.keys(), key=default_sort_key): + eig_basis = [] + + for block_eig, size in block_structure: + if block_eig != eig: + continue + + null_big = (eig_mat(eig, size)).nullspace() + null_small = (eig_mat(eig, size - 1)).nullspace() + + # we want to pick something that is in the big basis + # and not the small, but also something that is independent + # of any other generalized eigenvectors from a different + # generalized eigenspace sharing the same eigenvalue. + vec = pick_vec(null_small + eig_basis, null_big) + new_vecs = [eig_mat(eig, i).multiply(vec, dotprodsimp=None) + for i in range(size)] + + eig_basis.extend(new_vecs) + jordan_basis.extend(reversed(new_vecs)) + + basis_mat = mat.hstack(*jordan_basis) + + return restore_floats(basis_mat, jordan_mat) + + +def _left_eigenvects(M, **flags): + """Returns left eigenvectors and eigenvalues. + + This function returns the list of triples (eigenval, multiplicity, + basis) for the left eigenvectors. Options are the same as for + eigenvects(), i.e. the ``**flags`` arguments gets passed directly to + eigenvects(). + + Examples + ======== + + >>> from sympy import Matrix + >>> M = Matrix([[0, 1, 1], [1, 0, 0], [1, 1, 1]]) + >>> M.eigenvects() + [(-1, 1, [Matrix([ + [-1], + [ 1], + [ 0]])]), (0, 1, [Matrix([ + [ 0], + [-1], + [ 1]])]), (2, 1, [Matrix([ + [2/3], + [1/3], + [ 1]])])] + >>> M.left_eigenvects() + [(-1, 1, [Matrix([[-2, 1, 1]])]), (0, 1, [Matrix([[-1, -1, 1]])]), (2, + 1, [Matrix([[1, 1, 1]])])] + + """ + + eigs = M.transpose().eigenvects(**flags) + + return [(val, mult, [l.transpose() for l in basis]) for val, mult, basis in eigs] + + +def _singular_values(M): + """Compute the singular values of a Matrix + + Examples + ======== + + >>> from sympy import Matrix, Symbol + >>> x = Symbol('x', real=True) + >>> M = Matrix([[0, 1, 0], [0, x, 0], [-1, 0, 0]]) + >>> M.singular_values() + [sqrt(x**2 + 1), 1, 0] + + See Also + ======== + + condition_number + """ + + if M.rows >= M.cols: + valmultpairs = M.H.multiply(M).eigenvals() + else: + valmultpairs = M.multiply(M.H).eigenvals() + + # Expands result from eigenvals into a simple list + vals = [] + + for k, v in valmultpairs.items(): + vals += [sqrt(k)] * v # dangerous! same k in several spots! + + # Pad with zeros if singular values are computed in reverse way, + # to give consistent format. + if len(vals) < M.cols: + vals += [M.zero] * (M.cols - len(vals)) + + # sort them in descending order + vals.sort(reverse=True, key=default_sort_key) + + return vals diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/exceptions.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/exceptions.py new file mode 100644 index 0000000000000000000000000000000000000000..bfc7cfa0bdffd59ff2bc5a9cd85cf9b04ed1a63d --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/exceptions.py @@ -0,0 +1,26 @@ +""" +Exceptions raised by the matrix module. +""" + + +class MatrixError(Exception): + pass + + +class ShapeError(ValueError, MatrixError): + """Wrong matrix shape""" + pass + + +class NonSquareMatrixError(ShapeError): + pass + + +class NonInvertibleMatrixError(ValueError, MatrixError): + """The matrix in not invertible (division by multidimensional zero error).""" + pass + + +class NonPositiveDefiniteMatrixError(ValueError, MatrixError): + """The matrix is not a positive-definite matrix.""" + pass diff --git a/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/graph.py b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/graph.py new file mode 100644 index 0000000000000000000000000000000000000000..4c6356db884cfcd3c759ada07ac559f43dbcbbcb --- /dev/null +++ b/miniconda3/envs/ladir/lib/python3.10/site-packages/sympy/matrices/graph.py @@ -0,0 +1,279 @@ +from sympy.utilities.iterables import \ + flatten, connected_components, strongly_connected_components +from .exceptions import NonSquareMatrixError + + +def _connected_components(M): + """Returns the list of connected vertices of the graph when + a square matrix is viewed as a weighted graph. + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix([ + ... [66, 0, 0, 68, 0, 0, 0, 0, 67], + ... [0, 55, 0, 0, 0, 0, 54, 53, 0], + ... [0, 0, 0, 0, 1, 2, 0, 0, 0], + ... [86, 0, 0, 88, 0, 0, 0, 0, 87], + ... [0, 0, 10, 0, 11, 12, 0, 0, 0], + ... [0, 0, 20, 0, 21, 22, 0, 0, 0], + ... [0, 45, 0, 0, 0, 0, 44, 43, 0], + ... [0, 35, 0, 0, 0, 0, 34, 33, 0], + ... [76, 0, 0, 78, 0, 0, 0, 0, 77]]) + >>> A.connected_components() + [[0, 3, 8], [1, 6, 7], [2, 4, 5]] + + Notes + ===== + + Even if any symbolic elements of the matrix can be indeterminate + to be zero mathematically, this only takes the account of the + structural aspect of the matrix, so they will considered to be + nonzero. + """ + if not M.is_square: + raise NonSquareMatrixError + + V = range(M.rows) + E = sorted(M.todok().keys()) + return connected_components((V, E)) + + +def _strongly_connected_components(M): + """Returns the list of strongly connected vertices of the graph when + a square matrix is viewed as a weighted graph. + + Examples + ======== + + >>> from sympy import Matrix + >>> A = Matrix([ + ... [44, 0, 0, 0, 43, 0, 45, 0, 0], + ... [0, 66, 62, 61, 0, 68, 0, 60, 67], + ... [0, 0, 22, 21, 0, 0, 0, 20, 0], + ... [0, 0, 12, 11, 0, 0, 0, 10, 0], + ... [34, 0, 0, 0, 33, 0, 35, 0, 0], + ... [0, 86, 82, 81, 0, 88, 0, 80, 87], + ... [54, 0, 0, 0, 53, 0, 55, 0, 0], + ... [0, 0, 2, 1, 0, 0, 0, 0, 0], + ... [0, 76, 72, 71, 0, 78, 0, 70, 77]]) + >>> A.strongly_connected_components() + [[0, 4, 6], [2, 3, 7], [1, 5, 8]] + """ + if not M.is_square: + raise NonSquareMatrixError + + # RepMatrix uses the more efficient DomainMatrix.scc() method + rep = getattr(M, '_rep', None) + if rep is not None: + return rep.scc() + + V = range(M.rows) + E = sorted(M.todok().keys()) + return strongly_connected_components((V, E)) + + +def _connected_components_decomposition(M): + """Decomposes a square matrix into block diagonal form only + using the permutations. + + Explanation + =========== + + The decomposition is in a form of $A = P^{-1} B P$ where $P$ is a + permutation matrix and $B$ is a block diagonal matrix. + + Returns + ======= + + P, B : PermutationMatrix, BlockDiagMatrix + *P* is a permutation matrix for the similarity transform + as in the explanation. And *B* is the block diagonal matrix of + the result of the permutation. + + If you would like to get the diagonal blocks from the + BlockDiagMatrix, see + :meth:`~sympy.matrices.expressions.blockmatrix.BlockDiagMatrix.get_diag_blocks`. + + Examples + ======== + + >>> from sympy import Matrix, pprint + >>> A = Matrix([ + ... [66, 0, 0, 68, 0, 0, 0, 0, 67], + ... [0, 55, 0, 0, 0, 0, 54, 53, 0], + ... [0, 0, 0, 0, 1, 2, 0, 0, 0], + ... [86, 0, 0, 88, 0, 0, 0, 0, 87], + ... [0, 0, 10, 0, 11, 12, 0, 0, 0], + ... [0, 0, 20, 0, 21, 22, 0, 0, 0], + ... [0, 45, 0, 0, 0, 0, 44, 43, 0], + ... [0, 35, 0, 0, 0, 0, 34, 33, 0], + ... [76, 0, 0, 78, 0, 0, 0, 0, 77]]) + + >>> P, B = A.connected_components_decomposition() + >>> pprint(P) + PermutationMatrix((1 3)(2 8 5 7 4 6)) + >>> pprint(B) + [[66 68 67] ] + [[ ] ] + [[86 88 87] 0 0 ] + [[ ] ] + [[76 78 77] ] + [ ] + [ [55 54 53] ] + [ [ ] ] + [ 0 [45 44 43] 0 ] + [ [ ] ] + [ [35 34 33] ] + [ ] + [ [0 1 2 ]] + [ [ ]] + [ 0 0 [10 11 12]] + [ [ ]] + [ [20 21 22]] + + >>> P = P.as_explicit() + >>> B = B.as_explicit() + >>> P.T*B*P == A + True + + Notes + ===== + + This problem corresponds to the finding of the connected components + of a graph, when a matrix is viewed as a weighted graph. + """ + from sympy.combinatorics.permutations import Permutation + from sympy.matrices.expressions.blockmatrix import BlockDiagMatrix + from sympy.matrices.expressions.permutation import PermutationMatrix + + iblocks = M.connected_components() + + p = Permutation(flatten(iblocks)) + P = PermutationMatrix(p) + + blocks = [] + for b in iblocks: + blocks.append(M[b, b]) + B = BlockDiagMatrix(*blocks) + return P, B + + +def _strongly_connected_components_decomposition(M, lower=True): + """Decomposes a square matrix into block triangular form only + using the permutations. + + Explanation + =========== + + The decomposition is in a form of $A = P^{-1} B P$ where $P$ is a + permutation matrix and $B$ is a block diagonal matrix. + + Parameters + ========== + + lower : bool + Makes $B$ lower block triangular when ``True``. + Otherwise, makes $B$ upper block triangular. + + Returns + ======= + + P, B : PermutationMatrix, BlockMatrix + *P* is a permutation matrix for the similarity transform + as in the explanation. And *B* is the block triangular matrix of + the result of the permutation. + + Examples + ======== + + >>> from sympy import Matrix, pprint + >>> A = Matrix([ + ... [44, 0, 0, 0, 43, 0, 45, 0, 0], + ... [0, 66, 62, 61, 0, 68, 0, 60, 67], + ... [0, 0, 22, 21, 0, 0, 0, 20, 0], + ... [0, 0, 12, 11, 0, 0, 0, 10, 0], + ... [34, 0, 0, 0, 33, 0, 35, 0, 0], + ... [0, 86, 82, 81, 0, 88, 0, 80, 87], + ... [54, 0, 0, 0, 53, 0, 55, 0, 0], + ... [0, 0, 2, 1, 0, 0, 0, 0, 0], + ... [0, 76, 72, 71, 0, 78, 0, 70, 77]]) + + A lower block triangular decomposition: + + >>> P, B = A.strongly_connected_components_decomposition() + >>> pprint(P) + PermutationMatrix((8)(1 4 3 2 6)(5 7)) + >>> pprint(B) + [[44 43 45] [0 0 0] [0 0 0] ] + [[ ] [ ] [ ] ] + [[34 33 35] [0 0 0] [0 0 0] ] + [[ ] [ ] [ ] ] + [[54 53 55] [0 0 0] [0 0 0] ] + [ ] + [ [0 0 0] [22 21 20] [0 0 0] ] + [ [ ] [ ] [ ] ] + [ [0 0 0] [12 11 10] [0 0 0] ] + [ [ ] [ ] [ ] ] + [ [0 0 0] [2 1 0 ] [0 0 0] ] + [ ] + [ [0 0 0] [62 61 60] [66 68 67]] + [ [ ] [ ] [ ]] + [ [0 0 0] [82 81 80] [86 88 87]] + [ [ ] [ ] [ ]] + [ [0 0 0] [72 71 70] [76 78 77]] + + >>> P = P.as_explicit() + >>> B = B.as_explicit() + >>> P.T * B * P == A + True + + An upper block triangular decomposition: + + >>> P, B = A.strongly_connected_components_decomposition(lower=False) + >>> pprint(P) + PermutationMatrix((0 1 5 7 4 3 2 8 6)) + >>> pprint(B) + [[66 68 67] [62 61 60] [0 0 0] ] + [[ ] [ ] [ ] ] + [[86 88 87] [82 81 80] [0 0 0] ] + [[ ] [ ] [ ] ] + [[76 78 77] [72 71 70] [0 0 0] ] + [ ] + [ [0 0 0] [22 21 20] [0 0 0] ] + [ [ ] [ ] [ ] ] + [ [0 0 0] [12 11 10] [0 0 0] ] + [ [ ] [ ] [ ] ] + [ [0 0 0] [2 1 0 ] [0 0 0] ] + [ ] + [ [0 0 0] [0 0 0] [44 43 45]] + [ [ ] [ ] [ ]] + [ [0 0 0] [0 0 0] [34 33 35]] + [ [ ] [ ] [ ]] + [ [0 0 0] [0 0 0] [54 53 55]] + + >>> P = P.as_explicit() + >>> B = B.as_explicit() + >>> P.T * B * P == A + True + """ + from sympy.combinatorics.permutations import Permutation + from sympy.matrices.expressions.blockmatrix import BlockMatrix + from sympy.matrices.expressions.permutation import PermutationMatrix + + iblocks = M.strongly_connected_components() + if not lower: + iblocks = list(reversed(iblocks)) + + p = Permutation(flatten(iblocks)) + P = PermutationMatrix(p) + + rows = [] + for a in iblocks: + cols = [] + for b in iblocks: + cols.append(M[a, b]) + rows.append(cols) + B = BlockMatrix(rows) + return P, B