> OK, in analogy with exising names we get AdditiveMagmaWithUnit That's also OK for me.
>> I'm not really sure, but maybe we could think of introducing a category >> that represents the axioms. AdditiveSemigroup is OK for associativity, >> but, according to https://en.wikipedia.org/wiki/Magma_%28algebra%29 >> there is also "unital magma", i.e. without associativity. > > AFAICS it is exactly AdditiveMagmaWithUnit (2 above). I don't care so much whether it is UnitalAdditiveMagma or AdditiveMagmaWithUnit. In fact, I cannot say which one I like better. At least "unital magma" should appear somewhere in the documentation, if it becomes the "...WithUnit" thing. >> Although "Abelian" seems to be used consistently, i.e. always only wrt. >> the + operation, why not continue using "Additive" and "Multiplicative" >> in the name to avoid confusion? I.e. we would have AbelianAdditiveGroup, >> AbelianMultiplicativeGroup, etc. >> >> Currently, we have Group reserved for *. The respective categories for + >> always include commutativity. Not perfect, I would say. So I would want >> AdditiveGroup and MultiplicativeGroup. > > Names can get quite long, like CancellationAbelianMonoid. I think > when we have opportunity to shorten names without confusion we > should use it. Well, yes, that's a good reason. But for me and probably also for others it's strange that AbelianMonoid does not inherit from Monoid. If it where AbelianAdditiveMonoid and AbelianMultiplicativeMonoid the inheritance (from AdditiveMonoid or MultiplicativeMonoid) would be clear. That's what I meant in my last mail by duplicating some category hierarchy. If names are to long for you then what about Monoid_* and Monoid_+? Although I don't like too many underscores in names, we could then also have Semigroup_\_/ and Semigroup_/_\ (instead of JoinSemigroup and MeetSemigroup). For the general category hierarchy, I'm rather in favour of long names that easily (intuitively?) allow to guess inheritance. I therefore opt to include "Additive" and "Multiplicative" for the two hierarchies wrt + and * and reserve the generic names (SemiGroup, Monoid, Group) for the time when we can rename operations or parametrize op-names in the category. Ralf -- You received this message because you are subscribed to the Google Groups "FriCAS - computer algebra system" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/fricas-devel. For more options, visit https://groups.google.com/d/optout.
