On Sat, Jul 18, 2009 at 5:34 PM, Vinzent Steinberg<[email protected]> wrote: > > On Jul 10, 5:11 pm, Christophe <[email protected]> wrote: >> Hello, >> I've two questions : >> >> 1. Is there a way to test is an expression is real ? By expression, I >> mean any kind of sympy command. > > See expression.is_real. But this will change when the new assumptions > system is in place. > >> 2. Why don't you use +oo rather than oo for the positive >> infinity. You should keep oo for complex infinity which is >> isusefull for holomorphic function with a zero at infinity for >> example. > > This might be clever, however, in sympy the is currently only "real" > infinity. People are used to write limit(..., x, oo). We definitely > need complex infinity, there has been a discussion about this > (regarding log(0), iirc).
In fact, we have a complex infinity already: In [1]: zoo Out[1]: zoo Ondrej --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
