Hi, I know this problem can be treated correctly as above. The example given here is just to say that using "diff" has to be more careful since
diff(f,x,y).subs([(x, a), (y,b)]) may be not equal to $lim_{(x,y)\to(a,b)} f(x,y)$. Thanks, cch -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to sy...@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.