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
-~----------~----~----~----~------~----~------~--~---

Reply via email to