Re: Q: Factor with Polynominals?

*To*: mathgroup at smc.vnet.net*Subject*: [mg26700] Re: Q: Factor with Polynominals?*From*: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>*Date*: Thu, 18 Jan 2001 00:57:09 -0500 (EST)*Organization*: Universitaet Leipzig*References*: <943d4e$chm@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Hi, witch one of the printed forms in: 3 x^2 + 3 y^2 + x + y^3 + y x^2 /. a__ + b__ /; ( Print[a + Factor[Plus[b]]]; False) :> "never come here" ??? Ok. Lets take the LeafCount[] to choose the most simple case lst = {}; 3 x^2 + 3 y^2 + x + y^3 + y x^2 /. a__ + b__ /; ( AppendTo[lst, a + Factor[Plus[b]]]; False) :> "also never come here"; Last[First[Sort[{LeafCount[#], #} & /@ lst, First[#1] < First[#2] &]]] Regards Jens Robert wrote: > > hello! > i'd like to factor polynominals, e. g. if i have an exspression like > > 3 x^2 + 3 y^2 + x + y^3 + y x^2, > > i'd like to get (i want to factor x^2+y^2): > > (x^2+y^2) (3 + y) + x. > > how can i achieve a result like this (also with other, more complicated > polynominals)? > > thanks, robert