On Friday, January 17, 2014 1:51:22 AM UTC+1, Aaron Meurer wrote: > > it seems it is not true if p > 0.5. > > No, this distribution is symmetric under *{ p ---> 1 - p, k ---> n - k }*substitution, it has surely to converge for
*0 <= p <= 1* > The summation module is just fine for this problem, though. It > computed the answer. There are many problems that it can't compute, > and for those we do need improvement. I don't know how many of them > come up in statistics. The so-called hypergeometric summations will be > the best in the current system, due to the meijerg algorithm. > > Is there any list of papers/algorithms about summations? > > > Even worse with a slight modification: > > > >>>> summation(binomial_dist*k, (k, 0, n)) > > TypeError: unsupported operand type(s) for *: 'NoneType' and 'Add' > > Well this is obviously a bug. Can you report it? > In any case, this again surely converges for *p < 1*, the mean (*p n*) is always finite. https://github.com/sympy/sympy/issues/2787 -- 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 sympy+unsubscr...@googlegroups.com. To post to this group, send email to sympy@googlegroups.com. Visit this group at http://groups.google.com/group/sympy. For more options, visit https://groups.google.com/groups/opt_out.