You can't substitute power series into the symbolic ring, since power series are not objects of the symbolic ring. It just doesn't make sense in general.
You can substitute power series into polynomials; This also makes mathematical sense: sage: f_symb (t1, t2) |--> t1*t2 sage: f_symb.polynomial(QQ) t1*t2 sage: _.parent() Multivariate Polynomial Ring in t1, t2 over Rational Field sage: f_symb.polynomial(QQ).subs(t1=x1, t2=x2) x1*x2 On Monday, January 14, 2013 9:39:00 PM UTC, marco nijmeijer wrote: > > Thank you. That is a good point although I still do not see how it solves > the issue. Suppose I define f_symb as > > f_symb(t1,t2)=t1*t2 > > to avoid the confusion of using identical variable-names meaning different > things, what would I have to do to convert f_symb to f such that I can do > the substitution? Help is much appreciated. > > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sage-support?hl=en.
