I assume you meant sage: v = P(5) sage: v(oo) A positive finite number
This is because the elements of QQ coerce to the parent of oo, which is the "signed infinity ring." This is so we have sage: P.<x> = PolynomialRing(QQ) sage: w = x + 5 sage: v = w - x w(1.0) 6.00000000000000 sage: v(1.0) 5.00000000000000 sage: parent(w(1.0)) is parent(v(1.0)) True I suppose now that we have pushouts we could let the result lie in the (affine) extension of the rationals. Manipulation with the unsigned infinity would yield the projective extension. There is the open question of what the parent of oo should be though. Some kind of affine extension of ZZ? On Thu, Jan 15, 2015 at 11:49 AM, <michalg0...@gmail.com> wrote: > I recently sumbled at following behaviour: > sage: P.<x> = PolynomialRing(QQ) > sage: w = x + 1 > sage: w(oo) > + Infinity > sage: v = 5 > sage: v(oo) > A positive finite number > > This behaviour is strange (altough works as desined). For nonconstant > polynomial it has the same effect as calculating limit, for constant > polynomial it gives (seemingly) non-sensical result. Could the default > behaviour be changed so in case of constant polynomial instead of coercing > operands it would return simply the value of the polynomial (5 in this > example)? > > Regards, > MG > > -- > 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 http://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 http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
