It is because it isn't implemented. You can look in sympy/comcrete/ summations.py at eval_sum_symbolic() to see what is implemented. If you want to implement it, feel free to send in a patch. Either way, you should create an issue for it, if there isn't one already.
By the way, Sum with a capitol 'S' just represents an unevaluated summation. We should probably pretty print that thing with a sigma. On Jul 30, 2009, at 5:39 PM, Phillip M. Feldman wrote: > > When I type something like the following, I would expect to get a > result of oo, indicating that the sum diverges to infinity: > > sum(1/n, (n, 2, oo)) > > Instead, I get the same thing back (actually not quite-- the 's' > changes to a capital 'S'). Any idea why this doesn't work? > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sympy?hl=en -~----------~----~----~----~------~----~------~--~---
