On Monday, September 7, 2015 at 9:37:58 AM UTC+3, Paul Royik wrote: > > I see this error when try to calculate limit of (-1)^x /sqrt(x) as x > approaches infinity. > Can somebody explain me what is the problem here? >
``(-1)^x`` is equal to ``exp(pi*I*x)``. As the function has no serial expansion at infinity, SymPy attempts to use Gruntz' algorithm. It is intended tor real functions, and SymPy assumes that everything is real. It knows that ``pi`` is real and positive and the same is assumed of ``x``. That leaves just one problem: what is the sign of I. Actually, there is currently no algorithm in SymPy capable of computing the limit (which is 0 as ``x`` tends to ``oo`` on the real line), -- 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 http://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/c08f8a91-64f9-40e8-afd9-aefcee4bd226%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
