On Wednesday, March 30, 2016 at 7:46:29 AM UTC-7, Pierre wrote: > > Come to think of it, I just spotted a little bug in libgap: > > sage: p= Permutation([ (1, 2, 3), (4, 5) ]) > sage: pp= libgap( p ); pp > > [ 2, 3, 1, 5, 4 ] > > Here pp is a list, not a permutation ! GAP should respond (1,2,3)(4,5), > regardless of Sage's default behaviour of printing permutations as lists. > > It looks like the best solution would be to equip "sage.combinat.permutation.StandardPermutations_n_with_category.element_class" with a `_libgap_()` method. It would probably mean implementing an efficient interface routine to create permutations in libgap, and call that from the _libgap_ method.
Mind you, sage: s=SymmetricGroup(3)([2,3,1]) sage: type(s) <type 'sage.groups.perm_gps.permgroup_element.PermutationGroupElement'> is an entirely different beast. I don't think that the two concepts "permutation-as-a-combinatorial-object" and "permutation-as-a-group-element" are entirely unified in sage. It also seems that "SymmetricGoup" has its elements live in a pexpect gap, not in libgap. It might be attractive to move that too. -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at https://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
