[sage-devel] Re: Shortest expressions in permutation groups with generators

2015-06-19 Thread Dima Pasechnik
On Friday, 19 June 2015 11:35:36 UTC+1, Christian Stump wrote: the reason must be efficiency. E.g. for permutation groups one would work with a strong generating set S, rather than the original generators; expressing an element in terms of S is very quick, and then you hold expressions

[sage-devel] Re: Shortest expressions in permutation groups with generators

2015-06-19 Thread Christian Stump
the reason must be efficiency. E.g. for permutation groups one would work with a strong generating set S, rather than the original generators; expressing an element in terms of S is very quick, and then you hold expressions for each element of S in terms of the original generators

[sage-devel] Re: Shortest expressions in permutation groups with generators

2015-06-19 Thread Christian Stump
GAP4 has 39.5-2 Factorization ( http://www.gap-system.org/Manuals/doc/ref/chap39.html) calling GAP from Sage is not hard... Thanks for your reply -- but I am still a little puzzled: gap has two algorithms to compute a word in generators. This one, and the one implemented in

[sage-devel] Re: Shortest expressions in permutation groups with generators

2015-06-19 Thread Dima Pasechnik
On Friday, 19 June 2015 09:02:49 UTC+1, Christian Stump wrote: GAP4 has 39.5-2 Factorization ( http://www.gap-system.org/Manuals/doc/ref/chap39.html) calling GAP from Sage is not hard... Thanks for your reply -- but I am still a little puzzled: gap has two algorithms to compute a word

[sage-devel] Re: Shortest expressions in permutation groups with generators

2015-06-18 Thread Dima Pasechnik
GAP4 has 39.5-2 Factorization (http://www.gap-system.org/Manuals/doc/ref/chap39.html) calling GAP from Sage is not hard... On Tuesday, 16 June 2015 17:02:35 UTC+1, Christian Stump wrote: Hi there, I wasn't able to find the following functionality: Let W = PermutationGroup(gens) be a