On Nov 15, 2:38 pm, Jeroen Demeyer <[email protected]> wrote: > On 2010-11-15 13:53, Niels wrote: > > > Hi, > > > I think the following is a bug (only complete factorization after 2 steps): > > Yes, it is a bug. The problem is with the upstream package PARI/GP.
Yes, it is a bug in pari. Note also the following: gp: poly = t^3 + (-4*a^3 + 2*a)*t^2 - 11/3*a^2*t + 2/3*a^3 - 4/3*a t^3 + (-4*a^3 + 2*a)*t^2 - 11/3*a^2*t + (2/3*a^3 - 4/3*a) gp: factornf(poly, a^4 - a^2 +1) [t + Mod(-2*a^3 + a, a^4 - a^2 + 1) 1] [t + Mod(-4/3*a^3 + 2/3*a, a^4 - a^2 + 1) 1] [t + Mod(-2/3*a^3 + 1/3*a, a^4 - a^2 + 1) 1] Which is the correct answer. Note that with the new pari, it is not needed nfinit any more. We should avoid calling R.nfinit in self.factor() and only use the nffactor command if the nf structure is already computed and cached. This is another issue that would not solve the problem though. -- To post to this group, send an email to [email protected] To unsubscribe from this group, send an email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
