test_singularityfunctions.py 1.2 KB

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  1. from sympy.integrals.singularityfunctions import singularityintegrate
  2. from sympy.core.function import Function
  3. from sympy.core.symbol import symbols
  4. from sympy.functions.special.singularity_functions import SingularityFunction
  5. x, a, n, y = symbols('x a n y')
  6. f = Function('f')
  7. def test_singularityintegrate():
  8. assert singularityintegrate(x, x) is None
  9. assert singularityintegrate(x + SingularityFunction(x, 9, 1), x) is None
  10. assert 4*singularityintegrate(SingularityFunction(x, a, 3), x) == 4*SingularityFunction(x, a, 4)/4
  11. assert singularityintegrate(5*SingularityFunction(x, 5, -2), x) == 5*SingularityFunction(x, 5, -1)
  12. assert singularityintegrate(6*SingularityFunction(x, 5, -1), x) == 6*SingularityFunction(x, 5, 0)
  13. assert singularityintegrate(x*SingularityFunction(x, 0, -1), x) == 0
  14. assert singularityintegrate((x - 5)*SingularityFunction(x, 5, -1), x) == 0
  15. assert singularityintegrate(SingularityFunction(x, 0, -1) * f(x), x) == f(0) * SingularityFunction(x, 0, 0)
  16. assert singularityintegrate(SingularityFunction(x, 1, -1) * f(x), x) == f(1) * SingularityFunction(x, 1, 0)
  17. assert singularityintegrate(y*SingularityFunction(x, 0, -1)**2, x) == \
  18. y*SingularityFunction(0, 0, -1)*SingularityFunction(x, 0, 0)