I was a bit surprised about the following: sage: k = ZZ["q"].hom(QQ["q"]) sage: isinstance(k, Morphism) True sage: m = ZZ["q,t"].hom(QQ["q,t"]) sage: isinstance(m, Morphism) False
However, I vaguely recall a discussion about morphisms between multivariate polynomial rings being problematic. Does my memory trick me? Martin -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/7835e8e0-9ba3-46c6-8978-8bdcc13b9290n%40googlegroups.com.
