Le samedi 20 août 2016 08:29:34 UTC+2, Dima Pasechnik a écrit : > > > > On Saturday, August 20, 2016 at 1:28:29 AM UTC+1, Robert Dodier wrote: >> >> On 2016-08-19, Montgomery-Smith, Stephen <ste...@missouri.edu> wrote: >> >> > sage: integrate(y*e^(-y),y,0,t) >> > >> > Huge amount of error messages deleted, followed by: >> > >> > ValueError: Computation failed since Maxima requested additional >> > constraints; using the 'assume' command before evaluation *may* help >> > (example of legal syntax is 'assume(t>0)', see `assume?` for more >> details) >> > Is t positive, negative or zero? >> >> > However the integral is an analytic function, and exists even if t is >> > negative or complex. >> >> On looking into the source code, I see Maxima is trying to classify the >> type of problem, and using asksign for that. Maxima can actually get the >> result without resorting to asksign, but it doesn't try that first. The >> relevant function, if anybody cares, is METHOD-BY-LIMITS in >> src/defint.lisp. >> >> I dunno if this is a bug. It is needlessly clumsy but not incorrect. >> >> I wonder why there is no attempt to compute the antiderivative first. >
No need to : sage: integrate(y*e^-y,y,0,t,algorithm="sympy") -(t + 1)*e^(-t) + 1 HTH, -- Emmanuel Charpentier -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at https://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
