On Thu, Jun 26, 2008 at 9:44 AM, Joel B. Mohler <[EMAIL PROTECTED]> wrote: > > Hi, > > I cannot figure out how to force sage to construct a ring as a multivariate > ring with only a single generator. In the past, I used MPolynomialRing to > force multi-variate implementation, but that is now deprecated. > > Specifically, the output below really bugs me. I had code relying on features > in the multi-variate implementation, but sage magically created a univariate > ring when I just happened to have a single variable (and thus a single-ton > list). > > # 3.0.3 > sage: PolynomialRing(QQ,names=['Y1']) > Univariate Polynomial Ring in Y1 over Rational Field > sage: PolynomialRing(QQ,names=['Y1','Y2']) > Multivariate Polynomial Ring in Y1, Y2 over Rational Field > > Is this a bug or a feature? Clearly, I think it's a bug :).
This is definitely a bug since the docs explicitly say: "PolynomialRing(base_ring, name, sparse=False) returns a univariate polynomial ring; all other input formats return a multivariate polynomial ring." and name is by definition a string. To get a multivariate polynomial ring in 1 variable give the number of variables explicitly: sage: PolynomialRing(QQ, 1, names=['Y1']) Multivariate Polynomial Ring in Y1 over Rational Field Please report this to trac (and fix it :-) ). William > > Of course, I'd also be happy if the univariate and multivariate implementation > were much more consistent. It always seemed to me that these implementations > got continually out-of-sync with each other as features got put into one > implementation and didn't always get implemented in others. This is > something that the review process should find and point out. > > -- > Joel > > > > -- William Stein Associate Professor of Mathematics University of Washington http://wstein.org --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
