Hi Simon, > On 2012-04-20, Mark Shimozono <msh...@math.vt.edu> wrote: >> You had mentioned the functor that, when applied to a group, creates >> the group algebra. >> I know about the algebra method for sets. Can one also get induced >> algebra morphisms this way too, >> as the name "functor" suggests should be possible?
> Also, what functor is it that you/Nicolas are/is talking about? I would > expect it to be a construction functor and thus provided in the module > sage.categories.pushout, but it isn't there. sage: ZA=ZZ.algebra(QQ,category=CommutativeAdditiveGroups()) This creates the group algebra of the group (ZZ, +) with rational coefficients. The construction sounds functorial to me, at least on objects. But it doesn't seem to have an accompanying way to work with morphisms. > Anyway. If there are problems with applying a functor to objects or > morphism, please look at the documentation of > sage.categories.functor.Functor Thanks for the pointer. I will probably end up implementing a "Laurent" functor from free modules with basis (over a domain R, say) to the group algebra over Frac(R) with group being the additive free module. I already did the "object" part of the functor in a special case (weight lattice ---> group algebra of weight lattice) and find myself repeatedly redoing the "morphism" part for various operators on weight lattices. Which means I should just make a functor. --Mark -- You received this message because you are subscribed to the Google Groups "sage-combinat-devel" group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
