Hi guys, This is so simple that probably someone else has already noticed it, but just in case:
sage: x,t = var('x,t') sage: f = (1-x)/(1-x*cos(t)) sage: f(x=1) 0 sage: f(t=0)(x=1) 1 The second one is, of course, the correct answer. (FYI, Mathematica9 fails, too.) Wouldn't the first one return some sort of conditional expression: "if t=0 then 1, else 0" I would be happy to help in the debugging, if I can get some indication of what is running in the background, i.e. what function is called when one does the substitution "f(x=1)". Cheers, Jesús Torrado -- 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 http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.