Comment #2 on issue 1244 by nicolas.pourcelot: (x + exp(x)).is_positive returns True http://code.google.com/p/sympy/issues/detail?id=1244
Infact, exp(x) + anything atomic is returned as True. It seems to be linked to this : >>> sympy.exp(x).is_unbounded True which is all right. But in Add, I found this : def _eval_is_positive(self): c = self.args[0] r = Add(*self.args[1:]) if c.is_positive and r.is_positive: return True if c.is_unbounded: if r.is_unbounded: # either c or r is negative return else: return c.is_positive elif r.is_unbounded: return r.is_positive if c.is_nonnegative and r.is_positive: return True if r.is_nonnegative and c.is_positive: return True if c.is_nonpositive and r.is_nonpositive: return False why should an unbounded element give the sign of an addition ?? I have one question more : >>> sympy.exp(x).is_finite False I expected it to be True or None, not False, so what does is_finite mean ? Thanks ! -- You received this message because you are listed in the owner or CC fields of this issue, or because you starred this issue. You may adjust your issue notification preferences at: http://code.google.com/hosting/settings --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy-issues" group. To post to this group, send email to sympy-issues@googlegroups.com To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en -~----------~----~----~----~------~----~------~--~---