| from sympy.core.numbers import I |
| from sympy.core.symbol import symbols |
| from sympy.functions.elementary.exponential import exp |
| from sympy.functions.elementary.trigonometric import (cos, cot, sin) |
| from sympy.testing.pytest import _both_exp_pow |
|
|
| x, y, z, n = symbols('x,y,z,n') |
|
|
|
|
| @_both_exp_pow |
| def test_has(): |
| assert cot(x).has(x) |
| assert cot(x).has(cot) |
| assert not cot(x).has(sin) |
| assert sin(x).has(x) |
| assert sin(x).has(sin) |
| assert not sin(x).has(cot) |
| assert exp(x).has(exp) |
|
|
|
|
| @_both_exp_pow |
| def test_sin_exp_rewrite(): |
| assert sin(x).rewrite(sin, exp) == -I/2*(exp(I*x) - exp(-I*x)) |
| assert sin(x).rewrite(sin, exp).rewrite(exp, sin) == sin(x) |
| assert cos(x).rewrite(cos, exp).rewrite(exp, cos) == cos(x) |
| assert (sin(5*y) - sin( |
| 2*x)).rewrite(sin, exp).rewrite(exp, sin) == sin(5*y) - sin(2*x) |
| assert sin(x + y).rewrite(sin, exp).rewrite(exp, sin) == sin(x + y) |
| assert cos(x + y).rewrite(cos, exp).rewrite(exp, cos) == cos(x + y) |
| |
| assert cos(x).rewrite(cos, exp).rewrite(exp, sin) == cos(x) |
|
|
