Nils, See http://trac.sagemath.org/sage_trac/ticket/8502. I had found that, depending on the base ring, the result of evaluating all the variables was sometimes in the coefficient ring and sometimes a (constant) polynomial. So I fixed it -- I think. But the result is clearly not perfect.
John On 11 June 2010 20:07, Nils Bruin <nbr...@sfu.ca> wrote: > I would expect that when one evaluates a polynomial, only the coercion > properties of the *base ring* of the polynomial ring relative to the > ring of definition of the evaluation point are important, but the > example below gave me an unexpected negative answer. > > The fact that R is has an automatic coercion to S in the first example > but not in the second seems to affect the result. I would have > expected the result of the second example in both cases. > > sage: R=QQ['x'] > sage: S=QQ['x','y'] > sage: h=S.0^2 > sage: parent(h(R.0,0)) > Multivariate Polynomial Ring in x, y over Rational Field > > sage: R=QQ['x'] > sage: S=QQ['u','v'] > sage: h=S.0^2 > sage: parent(h(R.0,0)) > Univariate Polynomial Ring in x over Rational Field > > -- > To post to this group, send an email to sage-devel@googlegroups.com > To unsubscribe from this group, send an email to > sage-devel+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/sage-devel > URL: http://www.sagemath.org > -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
