Remarkable is that for f = x^4+1/(b)*(1/zzz) f is correctly translated to Singular:
sage: K0=GF(11) sage: #K0=QQ sage: R0.<b>=K0[] sage: K.<b>=K0.extension(b^5+4) sage: R1.<zzz>=K[] sage: L=FractionField(R1) sage: R.<x>=L[] sage: f=x^4+1/(b)*(1/zzz) sage: f._singular_() -1/(4*zzz)*b^4+x^4 That looks problematic, but is likely a different issue from what happens > on the asksage question. > I think it is the same issue. I checked that Singular is called to compute the roots using Singulars factorize() method. But even if *f* would be correctly translated to Singular the example at AskSage would not work, since Singulars factorize() behaves unexpectedly in quotient rings; example (in Singular): ring rng = 0,(x,b),lp; short = 0; qring qr = b^2-2; poly f = x^2-2; factorize(f); // expecting: (x-b)*(x+b) ? [1]: _[1]=1 _[2]=x^2-2 [2]: 1,1 Probably I should open a ticket and move the discussion to the ticket Am Mittwoch, 3. Dezember 2014 17:54:19 UTC+1 schrieb Nils Bruin: > > On Wednesday, December 3, 2014 3:07:14 AM UTC-8, Jakob Kroeker wrote: >> >> ... >> sage: f=x^4+1/(b*zzz) >> sage: f._singular_() # where is the fraction 1/(b*zzz) ? >> x^4 >> > ... >> > see also >> http://ask.sagemath.org/question/25083/bug-in-roots/ >> > > That looks problematic, but is likely a different issue from what happens > on the asksage question. I think we use libsingular for pretty much all > internal singular uses. We don't use the expect interface to singular for > communication there. > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
