general question: Is there something like integrate.quad for discrete integration sum of f(i) over integers (with or without finite bounds) the main point is to figure out some termination condition scipy.stats has a "home made" function, but we ran into a problem where the summation stops too soon. Are there any good rules when to stop summing terms? usually we just benefit from the `special` functions. our special case f(i) = g(i) * p(i) where p(i) is the probability mass function, and g(i) could be any function Josef