Karim BELABAS on Thu, 5 Nov 1998 13:00:01 +0100 (MET)

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Re: Memory use when factoring big polynomials

> > I must say polynomial factorization has improved dramatically from
> > 2.0.11 to upcoming 2.0.12.  Right now, there're only 2 other packages
> > ( and I've tried them many ) which beat PARI by a factor of several.
> You mean that there are only two packages which can factor x^2 - y^2? :-(

Actually, it is trivial to implement a very crude form of multivariate
factorisation (using Kronecker's trick. I just spent 5 minutes implementing
it in GP). It certainly wouldn't be able to match the standard packages (I
guess they all use some clever multivariate Hensel lift), but it might
succeed with x^2 - y^2 in a sensible amount of time (in GP it does...)

I'll include that in 2.0.13 (_really_ time to release 2.0.12.alpha now, if I
try to include other improvements now, it will again be delayed...)

Karim Belabas                    email: Karim.Belabas@math.u-psud.fr
Dep. de Mathematiques, Bat. 425
Universite Paris-Sud             Tel: (00 33) 1 69 15 57 48
F-91405 Orsay (France)           Fax: (00 33) 1 69 15 60 19
PARI/GP Home Page: http://pari.home.ml.org