On Sat, Nov 20, 2010 at 10:35 AM, VictorMiller <[email protected]> wrote: > I have the following: > > sage: R.<a,b> = QQ[] > sage: K = FractionField(R) > sage: S.<x,y> = K[] > > I then create an ideal, J, in S. I'd like to take various > specializations of the base. That is I have a homomorphism which maps > a and b to specific values in Q, and I'd like to form the ideal in a > bivariate polynomial ring QQ[] which is the specialization of this > ideal. I almost had it by first using J.subs({a:value,b:value}) but > that doesn't change the base, and Sage complains when I try to do a > change_ring on the specialized version of J since the base field is > still K and not QQ. It would be nice if change_ring could be > supplemented by allowing a morphism instead of a ring. If that were > specified then the source should be the original ring and the new > ideal (or other things that have a change_ring method) would be > obtained by applying that morphism. In some sense that's what's done > now, but the morphism used is the implicit coercion. > > Victor
This is exactly the problem that the patch here solves: http://trac.sagemath.org/sage_trac/ticket/8807 It's evidently not in Sage yet though. So you *have* to try it out and report on that ticket. -- William -- William -- To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
