Factorisation mod p sometimes hangs

[martinralbrecht@…]

Consider this code:

> ring r = 3,(x0,x1,x2),dp;
> poly p = -x0^3*x1^2*x2 - x0^2*x1^3*x2 + x0^2*x1*x2^3 + x0*x1^2*x2^3 - x0^3*x1^2 + x0^3*x1*x2 + x0^2*x1*x2^2 + x0*x1*x2^3 + x0^3*x1 + x0^2*x1*x2 + x0*x2^3 + x1*x2^3 + x0^2*x2 + x0*x1*x2 + x0*x2^2 + x2^3 + x0^2 - x0*x2 + x1*x2 + x0 + x2;
> factorize(p);

Occasionally, it will hang while most of the time the factorisation is quick. I'm running Singular 3-1-1 as shipped with Sage 2.6

[martinralbrecht@…]

Hi, will the fix be in the next Singular version or is the problem already fixed in Singular 3-1-2? Btw. I used this script hXXp://trac.sagemath.org/sage_trac/attachment/ticket/5074/review_5313.sage to find examples where the factorisation mod p has problems.

[mlee]

Hi, the fix will be in the next Singular version, it's not included in Singular 3-1-2.