On 3 October 2016 at 11:01, Kwankyu <ekwan...@gmail.com> wrote: > Hi, > > I want to do linear algebra over a valuation ring (infinite) R of rational > function field. As R is a PID, I expected the Sage machinery over general > PID works fine for it. But it does not. The problem is, as I understand it, > that internally Sage assumes an ambient vector space over Frac(R)=k(x) for > its algorithms. Thus for example, f=1/x in Frac(R) has numerator and > denominator in k[x], rather than R. This kind of things break the machinery > for R. >
I don't quite understand the problem, since Frac(R)=k(x) anyway. Do you only have a problem when x is not in R, since otherwise k[x] is a subring of R anyway and the numerator / denominator are then correct (though perhaps not in the parent you prefer)? If so then the only problematic R is k[1/x] and it should work to make a change of variable. > I think for general PIDs at least, Sage should not assume the ambient vector > space over the fraction field, as this effectively limits possible PIDs to > ZZ for QQ, to k[x] for k(x)... > > Do I just misunderstand something? Or is this a genuine limitation of Sage? > > Thank you for reading. > > > > -- > 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 https://groups.google.com/group/sage-support. > For more options, visit https://groups.google.com/d/optout. -- 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 https://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
