smichr's gfactor branch at github has a (hopefully) more robust method for factoring. It relies on the standard factor that is part of polys but it does pre-processing of an expression with a gcdfactor routine. The gcdfactor pulls out terms that can be removed multiplicatively from all terms in an Add. Preprocessing also includes removing (in hopefully a non-destructive manner) terms that would cause the polys factor function to fail.
>>> factor(1/x-1/x**2) -(1 - x)/x**2 >>> factor(0.2+0.44*x) 1/5 + 11*x/25 >>> gcdfactors(_) # see below (1, 1/25, 1, 5 + 11*x) new functions: ========== o gcdfactors - returns a tuple: (sign, constant, gcd factors, residual expression) >>> gcdfactors(x**2*exp(x)+exp(x+y)*x/y) (1, 1, x*exp(x), x + exp(y)/y) o gcdfactor - returns the product of the gcdfactors tuple >>> gcdfactor(x**2*exp(x)+exp(x+y)*x/y) x*(x + exp(y)/y)*exp(x) o rgcd - returns the gcd of two rationals (igcd does not handle this if one of the terms is an integer)--perhaps igcd should just be changed to recognize the case when one of the terms has a non-trivial denominator If factoring is important to what you are doing perhaps you can throw some of your work at this branch and feed back any comments/failures. -- You received this message because you are subscribed to the Google Groups "sympy-patches" group. To post to this group, send email to sympy-patc...@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
