I agree that DiracDelta doesn't make sense except under an integral sign. But as a function that is 0 everywhere except for one point, in a limit, it can be replaced with 0, which is what SymPy's limit() appears to be doing. I am curious how you are ending up with an expression with a DiracDelta that you need to take a limit of, though.
Aaron Meurer On Sat, Aug 13, 2016 at 8:34 PM, Richard Fateman <[email protected]> wrote: > Since DiracDelta is a distribution, not a function, and presumably the > limit program is oriented toward finding limits of analytic functions, > it would be fairly reasonable for the limit program to not work on > this kind of expression. The mathematical context in which DiracDelta is > understood and useful is under an integral sign. > > I have not tried sympy on this example, but it seems to me > that expecting sympy to answer a poorly formulated question > "correctly" is not going to reveal a bug in the program. It > is "user error". > > RJF > > > On Saturday, August 13, 2016 at 5:25:22 AM UTC-7, SAMPAD SAHA wrote: >> >> Suppose I want to find the value of f(x) for >> f(x) = DiracDelta(x - 30) + Heaviside(x) at x = 30+ in sympy. How can we >> do this? >> >> Regards >> Sampad Kumar Saha >> Mathematics and Computing >> I.I.T. Kharagpur >> >> >> >> -- 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 https://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAKgW%3D6JAO7i1f-X6uw-WiiztsV%3DXh2Tt74crv3ULhFKr1oz2Bg%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
