That seems reasonable since fraction is allowing the expr to rewrite: >>> 2*e 2*(x + 1)/(x - 1) >>> fraction(_) (2*x + 2, x - 1)
On Friday, March 27, 2015 at 4:28:28 AM UTC-5, Paul Royik wrote: > > Both fraction and as_numer_denom return (2x+2, sin(x)+1) for expression > 2(x+1)/(sin(x)+1), i.e. they rewrite numerator and denominator. > I suggest simple fix for fraction: substitute last line return > Mul(*numer), Mul(*denom) with return Mul(*numer, evaluate=False), > Mul(*denom, evaluate=False) > For as_numer_denom fix seems harder to implement. > > Is it possible to change them? > > > On Friday, March 27, 2015 at 1:40:39 AM UTC+2, Aaron Meurer wrote: >> >> It looks like fraction takes into account assumptions, but on the >> other hand, it doesn't do any rewriting of the expression to combine >> sums of fractions (e.g., fraction(1/x + 1/y) gives (1/x + 1/y, 1), >> whereas (1/x + 1/y).as_numer_denom() gives (x + y, x*y)). >> >> Aaron Meurer >> >> On Thu, Mar 26, 2015 at 12:09 PM, Paul Royik <distan...@gmail.com> >> wrote: >> > I used as_numer_denom earlier and now found fraction. >> > Is there any difference between them? >> > >> > -- >> > You received this message because you are subscribed to the Google >> Groups >> > "sympy" group. >> > To unsubscribe from this group and stop receiving emails from it, send >> an >> > email to sympy+un...@googlegroups.com. >> > To post to this group, send email to sy...@googlegroups.com. >> > Visit this group at http://groups.google.com/group/sympy. >> > To view this discussion on the web visit >> > >> https://groups.google.com/d/msgid/sympy/64b73b09-213c-4735-a80b-f5a37a4c2766%40googlegroups.com. >> >> >> > For more options, visit https://groups.google.com/d/optout. >> > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sympy+unsubscr...@googlegroups.com. To post to this group, send email to sympy@googlegroups.com. Visit this group at http://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/12fcfa1f-5701-400f-ace6-31ee0aa00daf%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.