Comment #3 on issue 1520 by wflynny: Inconsistency in subs http://code.google.com/p/sympy/issues/detail?id=1520
So it's clear that (x*y).subs(2*x,1) return x*y. But how about expressions like 3*x*y instead of x*y. Should this return 3/2*y or not do the subs? I guess what I am asking is, should subs only do the substitution if expr_coeff/old_coeff > 1 or should it do it only when old_coeff | expr_coeff or what? What do you think it should do? Some examples for a clarity: expr_coeff/old_coeff > 1: works: (3*x*y).subs(2*x,1) -> 3/2 y fails: (3*x*y).subs(4*x,1) -> 3*x*y old_coeff | expr_coeff: works: (4*x*y).subs(2*x,1) -> 2*y fails: (4*x*y).subs(3*x,1) -> 4*x*y -- 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 -~----------~----~----~----~------~----~------~--~---