| | from operator import gt, lt |
| |
|
| | from .libmp.backend import xrange |
| |
|
| | from .functions.functions import SpecialFunctions |
| | from .functions.rszeta import RSCache |
| | from .calculus.quadrature import QuadratureMethods |
| | from .calculus.inverselaplace import LaplaceTransformInversionMethods |
| | from .calculus.calculus import CalculusMethods |
| | from .calculus.optimization import OptimizationMethods |
| | from .calculus.odes import ODEMethods |
| | from .matrices.matrices import MatrixMethods |
| | from .matrices.calculus import MatrixCalculusMethods |
| | from .matrices.linalg import LinearAlgebraMethods |
| | from .matrices.eigen import Eigen |
| | from .identification import IdentificationMethods |
| | from .visualization import VisualizationMethods |
| |
|
| | from . import libmp |
| |
|
| | class Context(object): |
| | pass |
| |
|
| | class StandardBaseContext(Context, |
| | SpecialFunctions, |
| | RSCache, |
| | QuadratureMethods, |
| | LaplaceTransformInversionMethods, |
| | CalculusMethods, |
| | MatrixMethods, |
| | MatrixCalculusMethods, |
| | LinearAlgebraMethods, |
| | Eigen, |
| | IdentificationMethods, |
| | OptimizationMethods, |
| | ODEMethods, |
| | VisualizationMethods): |
| |
|
| | NoConvergence = libmp.NoConvergence |
| | ComplexResult = libmp.ComplexResult |
| |
|
| | def __init__(ctx): |
| | ctx._aliases = {} |
| | |
| | SpecialFunctions.__init__(ctx) |
| | RSCache.__init__(ctx) |
| | QuadratureMethods.__init__(ctx) |
| | LaplaceTransformInversionMethods.__init__(ctx) |
| | CalculusMethods.__init__(ctx) |
| | MatrixMethods.__init__(ctx) |
| |
|
| | def _init_aliases(ctx): |
| | for alias, value in ctx._aliases.items(): |
| | try: |
| | setattr(ctx, alias, getattr(ctx, value)) |
| | except AttributeError: |
| | pass |
| |
|
| | _fixed_precision = False |
| |
|
| | |
| | verbose = False |
| |
|
| | def warn(ctx, msg): |
| | print("Warning:", msg) |
| |
|
| | def bad_domain(ctx, msg): |
| | raise ValueError(msg) |
| |
|
| | def _re(ctx, x): |
| | if hasattr(x, "real"): |
| | return x.real |
| | return x |
| |
|
| | def _im(ctx, x): |
| | if hasattr(x, "imag"): |
| | return x.imag |
| | return ctx.zero |
| |
|
| | def _as_points(ctx, x): |
| | return x |
| |
|
| | def fneg(ctx, x, **kwargs): |
| | return -ctx.convert(x) |
| |
|
| | def fadd(ctx, x, y, **kwargs): |
| | return ctx.convert(x)+ctx.convert(y) |
| |
|
| | def fsub(ctx, x, y, **kwargs): |
| | return ctx.convert(x)-ctx.convert(y) |
| |
|
| | def fmul(ctx, x, y, **kwargs): |
| | return ctx.convert(x)*ctx.convert(y) |
| |
|
| | def fdiv(ctx, x, y, **kwargs): |
| | return ctx.convert(x)/ctx.convert(y) |
| |
|
| | def fsum(ctx, args, absolute=False, squared=False): |
| | if absolute: |
| | if squared: |
| | return sum((abs(x)**2 for x in args), ctx.zero) |
| | return sum((abs(x) for x in args), ctx.zero) |
| | if squared: |
| | return sum((x**2 for x in args), ctx.zero) |
| | return sum(args, ctx.zero) |
| |
|
| | def fdot(ctx, xs, ys=None, conjugate=False): |
| | if ys is not None: |
| | xs = zip(xs, ys) |
| | if conjugate: |
| | cf = ctx.conj |
| | return sum((x*cf(y) for (x,y) in xs), ctx.zero) |
| | else: |
| | return sum((x*y for (x,y) in xs), ctx.zero) |
| |
|
| | def fprod(ctx, args): |
| | prod = ctx.one |
| | for arg in args: |
| | prod *= arg |
| | return prod |
| |
|
| | def nprint(ctx, x, n=6, **kwargs): |
| | """ |
| | Equivalent to ``print(nstr(x, n))``. |
| | """ |
| | print(ctx.nstr(x, n, **kwargs)) |
| |
|
| | def chop(ctx, x, tol=None): |
| | """ |
| | Chops off small real or imaginary parts, or converts |
| | numbers close to zero to exact zeros. The input can be a |
| | single number or an iterable:: |
| | |
| | >>> from mpmath import * |
| | >>> mp.dps = 15; mp.pretty = False |
| | >>> chop(5+1e-10j, tol=1e-9) |
| | mpf('5.0') |
| | >>> nprint(chop([1.0, 1e-20, 3+1e-18j, -4, 2])) |
| | [1.0, 0.0, 3.0, -4.0, 2.0] |
| | |
| | The tolerance defaults to ``100*eps``. |
| | """ |
| | if tol is None: |
| | tol = 100*ctx.eps |
| | try: |
| | x = ctx.convert(x) |
| | absx = abs(x) |
| | if abs(x) < tol: |
| | return ctx.zero |
| | if ctx._is_complex_type(x): |
| | |
| | part_tol = max(tol, absx*tol) |
| | if abs(x.imag) < part_tol: |
| | return x.real |
| | if abs(x.real) < part_tol: |
| | return ctx.mpc(0, x.imag) |
| | except TypeError: |
| | if isinstance(x, ctx.matrix): |
| | return x.apply(lambda a: ctx.chop(a, tol)) |
| | if hasattr(x, "__iter__"): |
| | return [ctx.chop(a, tol) for a in x] |
| | return x |
| |
|
| | def almosteq(ctx, s, t, rel_eps=None, abs_eps=None): |
| | r""" |
| | Determine whether the difference between `s` and `t` is smaller |
| | than a given epsilon, either relatively or absolutely. |
| | |
| | Both a maximum relative difference and a maximum difference |
| | ('epsilons') may be specified. The absolute difference is |
| | defined as `|s-t|` and the relative difference is defined |
| | as `|s-t|/\max(|s|, |t|)`. |
| | |
| | If only one epsilon is given, both are set to the same value. |
| | If none is given, both epsilons are set to `2^{-p+m}` where |
| | `p` is the current working precision and `m` is a small |
| | integer. The default setting typically allows :func:`~mpmath.almosteq` |
| | to be used to check for mathematical equality |
| | in the presence of small rounding errors. |
| | |
| | **Examples** |
| | |
| | >>> from mpmath import * |
| | >>> mp.dps = 15 |
| | >>> almosteq(3.141592653589793, 3.141592653589790) |
| | True |
| | >>> almosteq(3.141592653589793, 3.141592653589700) |
| | False |
| | >>> almosteq(3.141592653589793, 3.141592653589700, 1e-10) |
| | True |
| | >>> almosteq(1e-20, 2e-20) |
| | True |
| | >>> almosteq(1e-20, 2e-20, rel_eps=0, abs_eps=0) |
| | False |
| | |
| | """ |
| | t = ctx.convert(t) |
| | if abs_eps is None and rel_eps is None: |
| | rel_eps = abs_eps = ctx.ldexp(1, -ctx.prec+4) |
| | if abs_eps is None: |
| | abs_eps = rel_eps |
| | elif rel_eps is None: |
| | rel_eps = abs_eps |
| | diff = abs(s-t) |
| | if diff <= abs_eps: |
| | return True |
| | abss = abs(s) |
| | abst = abs(t) |
| | if abss < abst: |
| | err = diff/abst |
| | else: |
| | err = diff/abss |
| | return err <= rel_eps |
| |
|
| | def arange(ctx, *args): |
| | r""" |
| | This is a generalized version of Python's :func:`~mpmath.range` function |
| | that accepts fractional endpoints and step sizes and |
| | returns a list of ``mpf`` instances. Like :func:`~mpmath.range`, |
| | :func:`~mpmath.arange` can be called with 1, 2 or 3 arguments: |
| | |
| | ``arange(b)`` |
| | `[0, 1, 2, \ldots, x]` |
| | ``arange(a, b)`` |
| | `[a, a+1, a+2, \ldots, x]` |
| | ``arange(a, b, h)`` |
| | `[a, a+h, a+h, \ldots, x]` |
| | |
| | where `b-1 \le x < b` (in the third case, `b-h \le x < b`). |
| | |
| | Like Python's :func:`~mpmath.range`, the endpoint is not included. To |
| | produce ranges where the endpoint is included, :func:`~mpmath.linspace` |
| | is more convenient. |
| | |
| | **Examples** |
| | |
| | >>> from mpmath import * |
| | >>> mp.dps = 15; mp.pretty = False |
| | >>> arange(4) |
| | [mpf('0.0'), mpf('1.0'), mpf('2.0'), mpf('3.0')] |
| | >>> arange(1, 2, 0.25) |
| | [mpf('1.0'), mpf('1.25'), mpf('1.5'), mpf('1.75')] |
| | >>> arange(1, -1, -0.75) |
| | [mpf('1.0'), mpf('0.25'), mpf('-0.5')] |
| | |
| | """ |
| | if not len(args) <= 3: |
| | raise TypeError('arange expected at most 3 arguments, got %i' |
| | % len(args)) |
| | if not len(args) >= 1: |
| | raise TypeError('arange expected at least 1 argument, got %i' |
| | % len(args)) |
| | |
| | a = 0 |
| | dt = 1 |
| | |
| | if len(args) == 1: |
| | b = args[0] |
| | elif len(args) >= 2: |
| | a = args[0] |
| | b = args[1] |
| | if len(args) == 3: |
| | dt = args[2] |
| | a, b, dt = ctx.mpf(a), ctx.mpf(b), ctx.mpf(dt) |
| | assert a + dt != a, 'dt is too small and would cause an infinite loop' |
| | |
| | if a > b: |
| | if dt > 0: |
| | return [] |
| | op = gt |
| | else: |
| | if dt < 0: |
| | return [] |
| | op = lt |
| | |
| | result = [] |
| | i = 0 |
| | t = a |
| | while 1: |
| | t = a + dt*i |
| | i += 1 |
| | if op(t, b): |
| | result.append(t) |
| | else: |
| | break |
| | return result |
| |
|
| | def linspace(ctx, *args, **kwargs): |
| | """ |
| | ``linspace(a, b, n)`` returns a list of `n` evenly spaced |
| | samples from `a` to `b`. The syntax ``linspace(mpi(a,b), n)`` |
| | is also valid. |
| | |
| | This function is often more convenient than :func:`~mpmath.arange` |
| | for partitioning an interval into subintervals, since |
| | the endpoint is included:: |
| | |
| | >>> from mpmath import * |
| | >>> mp.dps = 15; mp.pretty = False |
| | >>> linspace(1, 4, 4) |
| | [mpf('1.0'), mpf('2.0'), mpf('3.0'), mpf('4.0')] |
| | |
| | You may also provide the keyword argument ``endpoint=False``:: |
| | |
| | >>> linspace(1, 4, 4, endpoint=False) |
| | [mpf('1.0'), mpf('1.75'), mpf('2.5'), mpf('3.25')] |
| | |
| | """ |
| | if len(args) == 3: |
| | a = ctx.mpf(args[0]) |
| | b = ctx.mpf(args[1]) |
| | n = int(args[2]) |
| | elif len(args) == 2: |
| | assert hasattr(args[0], '_mpi_') |
| | a = args[0].a |
| | b = args[0].b |
| | n = int(args[1]) |
| | else: |
| | raise TypeError('linspace expected 2 or 3 arguments, got %i' \ |
| | % len(args)) |
| | if n < 1: |
| | raise ValueError('n must be greater than 0') |
| | if not 'endpoint' in kwargs or kwargs['endpoint']: |
| | if n == 1: |
| | return [ctx.mpf(a)] |
| | step = (b - a) / ctx.mpf(n - 1) |
| | y = [i*step + a for i in xrange(n)] |
| | y[-1] = b |
| | else: |
| | step = (b - a) / ctx.mpf(n) |
| | y = [i*step + a for i in xrange(n)] |
| | return y |
| |
|
| | def cos_sin(ctx, z, **kwargs): |
| | return ctx.cos(z, **kwargs), ctx.sin(z, **kwargs) |
| |
|
| | def cospi_sinpi(ctx, z, **kwargs): |
| | return ctx.cospi(z, **kwargs), ctx.sinpi(z, **kwargs) |
| |
|
| | def _default_hyper_maxprec(ctx, p): |
| | return int(1000 * p**0.25 + 4*p) |
| |
|
| | _gcd = staticmethod(libmp.gcd) |
| | list_primes = staticmethod(libmp.list_primes) |
| | isprime = staticmethod(libmp.isprime) |
| | bernfrac = staticmethod(libmp.bernfrac) |
| | moebius = staticmethod(libmp.moebius) |
| | _ifac = staticmethod(libmp.ifac) |
| | _eulernum = staticmethod(libmp.eulernum) |
| | _stirling1 = staticmethod(libmp.stirling1) |
| | _stirling2 = staticmethod(libmp.stirling2) |
| |
|
| | def sum_accurately(ctx, terms, check_step=1): |
| | prec = ctx.prec |
| | try: |
| | extraprec = 10 |
| | while 1: |
| | ctx.prec = prec + extraprec + 5 |
| | max_mag = ctx.ninf |
| | s = ctx.zero |
| | k = 0 |
| | for term in terms(): |
| | s += term |
| | if (not k % check_step) and term: |
| | term_mag = ctx.mag(term) |
| | max_mag = max(max_mag, term_mag) |
| | sum_mag = ctx.mag(s) |
| | if sum_mag - term_mag > ctx.prec: |
| | break |
| | k += 1 |
| | cancellation = max_mag - sum_mag |
| | if cancellation != cancellation: |
| | break |
| | if cancellation < extraprec or ctx._fixed_precision: |
| | break |
| | extraprec += min(ctx.prec, cancellation) |
| | return s |
| | finally: |
| | ctx.prec = prec |
| |
|
| | def mul_accurately(ctx, factors, check_step=1): |
| | prec = ctx.prec |
| | try: |
| | extraprec = 10 |
| | while 1: |
| | ctx.prec = prec + extraprec + 5 |
| | max_mag = ctx.ninf |
| | one = ctx.one |
| | s = one |
| | k = 0 |
| | for factor in factors(): |
| | s *= factor |
| | term = factor - one |
| | if (not k % check_step): |
| | term_mag = ctx.mag(term) |
| | max_mag = max(max_mag, term_mag) |
| | sum_mag = ctx.mag(s-one) |
| | |
| | |
| | if -term_mag > ctx.prec: |
| | break |
| | k += 1 |
| | cancellation = max_mag - sum_mag |
| | if cancellation != cancellation: |
| | break |
| | if cancellation < extraprec or ctx._fixed_precision: |
| | break |
| | extraprec += min(ctx.prec, cancellation) |
| | return s |
| | finally: |
| | ctx.prec = prec |
| |
|
| | def power(ctx, x, y): |
| | r"""Converts `x` and `y` to mpmath numbers and evaluates |
| | `x^y = \exp(y \log(x))`:: |
| | |
| | >>> from mpmath import * |
| | >>> mp.dps = 30; mp.pretty = True |
| | >>> power(2, 0.5) |
| | 1.41421356237309504880168872421 |
| | |
| | This shows the leading few digits of a large Mersenne prime |
| | (performing the exact calculation ``2**43112609-1`` and |
| | displaying the result in Python would be very slow):: |
| | |
| | >>> power(2, 43112609)-1 |
| | 3.16470269330255923143453723949e+12978188 |
| | """ |
| | return ctx.convert(x) ** ctx.convert(y) |
| |
|
| | def _zeta_int(ctx, n): |
| | return ctx.zeta(n) |
| |
|
| | def maxcalls(ctx, f, N): |
| | """ |
| | Return a wrapped copy of *f* that raises ``NoConvergence`` when *f* |
| | has been called more than *N* times:: |
| | |
| | >>> from mpmath import * |
| | >>> mp.dps = 15 |
| | >>> f = maxcalls(sin, 10) |
| | >>> print(sum(f(n) for n in range(10))) |
| | 1.95520948210738 |
| | >>> f(10) # doctest: +IGNORE_EXCEPTION_DETAIL |
| | Traceback (most recent call last): |
| | ... |
| | NoConvergence: maxcalls: function evaluated 10 times |
| | |
| | """ |
| | counter = [0] |
| | def f_maxcalls_wrapped(*args, **kwargs): |
| | counter[0] += 1 |
| | if counter[0] > N: |
| | raise ctx.NoConvergence("maxcalls: function evaluated %i times" % N) |
| | return f(*args, **kwargs) |
| | return f_maxcalls_wrapped |
| |
|
| | def memoize(ctx, f): |
| | """ |
| | Return a wrapped copy of *f* that caches computed values, i.e. |
| | a memoized copy of *f*. Values are only reused if the cached precision |
| | is equal to or higher than the working precision:: |
| | |
| | >>> from mpmath import * |
| | >>> mp.dps = 15; mp.pretty = True |
| | >>> f = memoize(maxcalls(sin, 1)) |
| | >>> f(2) |
| | 0.909297426825682 |
| | >>> f(2) |
| | 0.909297426825682 |
| | >>> mp.dps = 25 |
| | >>> f(2) # doctest: +IGNORE_EXCEPTION_DETAIL |
| | Traceback (most recent call last): |
| | ... |
| | NoConvergence: maxcalls: function evaluated 1 times |
| | |
| | """ |
| | f_cache = {} |
| | def f_cached(*args, **kwargs): |
| | if kwargs: |
| | key = args, tuple(kwargs.items()) |
| | else: |
| | key = args |
| | prec = ctx.prec |
| | if key in f_cache: |
| | cprec, cvalue = f_cache[key] |
| | if cprec >= prec: |
| | return +cvalue |
| | value = f(*args, **kwargs) |
| | f_cache[key] = (prec, value) |
| | return value |
| | f_cached.__name__ = f.__name__ |
| | f_cached.__doc__ = f.__doc__ |
| | return f_cached |
| |
|