I understand that from some point of view mixing groups and their representations is a bad idea, but many groups are naturally defined as transformation groups and using a matrix presentation is just as natural as describing them by permutations, or even more so. Not to mention the huge size some of the "constructions by permutations" have.
For groups with a canonical matrix form I'd vote for the mythical python construction. Surely everybody agrees PSL(2,16) has a "natural" presentation by 2x2 matrices over GF(16), and there is no reason we shouldn't be able to use it. But for groups where the matrix presentation is not canonical (eg the cyclic or dihedral groups) my vote is to construct them from the generators. Cheers, J On Thursday, July 19, 2012 7:29:57 AM UTC+1, Snark wrote: > > Le 19/07/2012 08:22, Dima Pasechnik a �crit : > > > It looks like a hack. IMHO representations and groups themselves should > > not be mixed in one glass. > > I agree on both points : > (1) mixing things in the same glass sometimes gives unwanted results ; > (2) putting both representations and groups in the same class doesn't > sound like a good idea. > > Snark on #sagemath > > PS: my favorite typo is when I want to have a look at a file and type > "mess filename" instead of "less filename"... it looks so like a > declaration of intention! > -- -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
