Singular

Dear Javier,

thank you for the suggestion. Yes, it's a nice idea to
return a different ring and make synchronization with
the way how "oppose" works. We'll keep it in mind.

With best regards,
Viktor

Dear friends,

I'm writting a library about Hopf algebras such that the underlying algebras structure fits the algebras managed by Singular, commutative and non-commutative ones. Since the antipode map in an antialgebra morphism I have decided to define it over the opposite algebra. The problem is that opposite([ring]) returns the same ring if it is commutative. However oppose() always returns the opposite element.

So I think that it would be better than the opposite() function always returns the same construction as in the non-commutative setting, i.e. changing lowercase to uppercase and changing the order of variables. This allows a more compact definition of new code.

Best,

Javier Lobillo