Could this be related ? http://trac.sagemath.org/ticket/16384
I do not understand much about categories, but if we implement multiplication by a positive integer for semigroups and multiplication by a negative integer for semigroup with inverse, won't this automatically give a ZZ-Module structure to any additive abelian group ? And more technically, isn't it the case that every additive abelian parent in Sage will be detected as a ZZ-Module ? Nathann On Tuesday, May 27, 2014 9:14:06 PM UTC+2, vdelecroix wrote: > > Hi, > > A module over ZZ is the same thing as an Abelian group. Why do we have > two distinct categories ? > > More concretely, I want to implement a function that takes any finite > Abelian group as input ? So my test would looks like > > def f(A): > assert A in CommutativeAdditiveGroups().Finite() > > or > > def f(A): > assert A in Modules(ZZ).Finite() > > Is there a preference ? Is there a way to merge Modules(ZZ) and > CommutativeAdditiveGroups() ? > > Vincent > -- 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 post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
