Thanks a bunch! I'll take a look. Alex
On Mar 28, 3:03 pm, David Joyner <wdjoy...@gmail.com> wrote: > I wrote this 3 days ago and somehow put it in drafts instead of > sending it. Hope it still helps. > > On Sat, Mar 24, 2012 at 10:53 PM, Aleksandar Makelov > > > > > > > > > > <amake...@college.harvard.edu> wrote: > > > On Mar 24, 10:39 pm, Aaron Meurer <asmeu...@gmail.com> wrote: > > >> How could it be too late? > > > Well yeah I hoped it's not :) I was wondering about that because it'd > > take a massive amount of changes over different modules to put all > > abstract algebraic structures on a common setting -- but I think > > that's the right direction to treat this stuff (like, abstract algebra > > is abstract so in order to implement it we need more abstractness :) ) > > >> Well the GAP people have obviously thought about this problem a lot > >> more than we have, and they have quite a bit implemented, so it is a > >> good place to look for references. Obviously, we will want to modify > >> some things to make them more Pythonic, or to make them fit better > >> with other parts of SymPy. For example, GAP is written in C, which is > >> not object oriented, so depending on how they implemented their data > >> structures, we may want to do it different (not to mention that Python > >> has its own independent set of data structures from C with their own > >> advantages and disadvantages). > > >> Aaron Meurer > > > Yep the GAP guys appear to be solid citizens. They have a 900 page > > reference and also all the C-code is freely available. Apart from that > > Sage also has a lot - in python or cython. See for > examplehttp://hg.sagemath.org/sage-main/file/c239be1054e0/sage/groups/perm_g... > However, their license is GPL, not BSD, so you can't use it directly. > Hopefully, it is another good reference for you to look at though. > You can see from the author field, it seems I wrote (many years ago) a > few of those > methods. Of course, I am more than happy to relicense any of my code as BSD, > in case that helps. > > > > > > > > > they have tables for a LOT of known finite groups. I think this is > > going to help a lot - they are referred to in Chapter 11 of The > > Handbook on Computational Group Theory and could speed up some of the > > algorithms. > > > -- > > You received this message because you are subscribed to the Google Groups > > "sympy" group. > > To post to this group, send email to sympy@googlegroups.com. > > To unsubscribe from this group, send email to > > sympy+unsubscr...@googlegroups.com. > > For more options, visit this group > > athttp://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
