>> You know that FriCAS/Aldor does not have this drawback? Eg., the set of all >> combinatorial species forms a Ring...
A semi-ring, we don't have virtual species yet. > Thanks for pointing this out. Could you make a quick summary here of > how this is achieved? I don't know what Martin refers to exactly, because he could have pointed to some code. > Each combinatorial species is a domain, right? Are they simultaneously > elements of some domain in the Ring category? Well, that is not completely fleshed out. (At least not in trunk of aldor-combinat.) But as you see at http://www.risc.uni-linz.ac.at/people/hemmecke/AldorCombinat/combinatsu27.html#x41-590008.14 you are approximately right. Elements of this CombinatorialSpeciesAlgebra domain are functions that produce combinatorial species. The 1 is clear, addition as well, 0 would also be simple. The X, maybe doesn't really belong there, since that already is a step towards a polynomial (semi)algebra. But otherwise, who cares at the moment? Well, that is just some idea... And I don't see why that cannot work in Aldor. I actually also don't see a big trouble that something along these lines would be impossible in Python. Or is it? I'd be happy to learn more how this can be achieved through python. Ralf --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
