Hi all, I've been running into issues computing Hilbert polynomials with Sage's default algorithm. For instance,
R.<x0,x1,x2,x3,x4,x5> = PolynomialRing(QQ, 6) I = R.ideal([x0*x2*x3^2*x4^2*x5, x2^2*x3^2*x4^2*x5, x2*x3^2*x4^2*x5^2, x2*x3^2*x4^3, x3^3*x4^3, x3^3*x4^2*x5, x1*x3*x4^3, x1*x3*x4^2*x5, x1*x2^3, x1*x2^2*x3, x1*x2*x3^2, x0^3, x0^2*x1, x0*x1^2, x1^3]) I.hilbert_polynomial() will die with an assertion error, but using singular instead with I.hilbert_polynomial(algorithm='singular') will work. I found ticket 27483 which seems to be dealing with a similar bug, but I'm using Sage 8.9 beta1 and their changes seem to be present in my version so it seems the fixes there do not address this issue (I think this ticket was merged in 8.8). Additionally the example cited in that ticket P.<x,y,z> = PolynomialRing(QQ) I = Ideal([x^3, x*y^2, y^4, x^2*y*z, y^3*z, x^2*z^2, x*y*z^2, x*z^3]) I.hilbert_polynomial() dies for me in the same manner but works using singular's algorithm. The test that was added by 27483 into the hilbert_polynomial function to cover this example actually uses singular's algorithm (i.e. there's no test that the default Sage algorithm is actually working). Also, in both these examples, Sage's algorithm for the Hilbert series does seem to be working correctly. Is this a current bug in Sage, or am I just missing some changes in my Sage version which would fix this? Thanks! Grayson -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/653113b6-e70f-4f9b-823b-854ad2bf4255%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
