On 10 November 2011 00:21, Raoul <[email protected]> wrote: > Hi, > > > > *concerning sums: > > > *In [1]: s = summation(k**(-x),(k,1,oo)) > > > > > > In [2]: s > > > Out[2]: > > > > > > ∞ > > > ___ > > > \ ` > > > \ -x > > > / k > > > /__, > > > k = 1 > > > > > > In [3]: fs = lambdify([x], s) # I've added a print statement inside > > > so I can see the lambda string > > > lambda x: (Sum(k**(-x), (k, 1, oo))) > > > > > > In [4]: fs(2) > > > /usr/lib/pymodules/python2.7/numpy/__init__.pyc in <lambda>(x) > > > > > > NameError: global name 'Sum' is not defined > > I suppose the function "Sum" just is not "translated" to > lamdified numpy/mpmath/... code. > > Yes, it is not translated and that is posing a problem.
> Further there is probably no equivalent to symbolic > infinite sums. > There is - the approximation used in evalf(). > > What would this sum be, for example in numerical code? > -- 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.
