Just following up with more information-- I get the feeling this is different than Issue 1696. I get this behavior, all of which I find unexpected:
In [1]: from sympy import * In [2]: from sympy.abc import x ## I would expect this to return S(1) without needing to evalf: In [3]: integrate(Heaviside(x),(x,-1,1)) Out[3]: Integral(Heaviside(x), (x, -1, 1)) In [4]: integrate(Heaviside(x),(x,-1,1)).n() Out[4]: 1.00000000000000 ## I would expect this to return Rational(1,2), strangely it doesn't even return an ## unevaluated integral, it seems certain the answer here is precisely zero. In [5]: integrate(Heaviside(x-Rational(1,2)),(x,-1,1)) Out[5]: 0 ## I would expect this to return S(1), what I get is far more complicated: In [6]: integrate(Heaviside(x-S(1)),(x,-1,2)) Out[6]: -meijerg(((2, 1), ()), ((), (1, 0)), 1) + meijerg(((2, 1), ()), ((), (1, 0)), 2) ## ...but evaluates correctly In [7]: integrate(Heaviside(x-S(1)),(x,-1,2)).n() Out[7]: 1.00000000000000 I get correct results spot evaluating Heaviside(x-Rational(1,2)) at various points. Is the problem in integrate? On Tuesday, March 5, 2013 12:43:11 AM UTC-8, G B wrote: > > Maybe this is a symptom of: > http://code.google.com/p/sympy/issues/detail?id=1696 > > but this command: > integrate(Heaviside(x-0.2)-Heaviside(x-0.5),(x,0.,1.)) > > returns zero for me. > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
