On Thu, Aug 30, 2012 at 8:22 PM, David Joyner <[email protected]> wrote: > On Thu, Aug 30, 2012 at 10:20 AM, Chris Smith <[email protected]> wrote: >>> >>> Permutation([(0, 2, 7, 5), (1, 4, 6, 3), (8, 32, 24, 16), (9, 33, 25,17), >>> (10, 34, 26, 18)]) >> >> Sorry, enter that as >> >> Permutation([(0, 2, 7, 5), (1, 4, 6, 3), (8, 32, 24, 16), (9, 33, >> 25,17), (10, 34, 26, 18)] , size=48) > > Thanks. Here we are:-) > > >>>> F = Permutation([(17,19,24,22),(18,21,23,20),( 6,25,43,16),( 7,28,42,13),( >>>> 8,30,41,11)], size=49) >>>> B = Permutation([(33,35,40,38),(34,37,39,36),( 3, 9,46,32),( 2,12,47,29),( >>>> 1,14,48,27)], size=49) >>>> L = Permutation([( 9,11,16,14),(10,13,15,12),( 1,17,41,40),( 4,20,44,37),( >>>> 6,22,46,35)], size=49) >>>> R = Permutation([ (25,27,32,30),(26,29,31,28),( 3,38,43,19),( >>>> 5,36,45,21),( 8,33,48,24)], size=49) >>>> U = Permutation([ ( 1, 3, 8, 6),( 2, 5, 7, 4),( >>>> 9,33,25,17),(10,34,26,18),(11,35,27,19)], size=49) >>>> D = Permutation([ >>>> (41,43,48,46),(42,45,47,44),(14,22,30,38),(15,23,31,39),(16,24,32,40)], >>>> size=49) >>>> G = PermutationGroup([F,B,L,R,U,D]) >>>> G.order() > 43252003274489856000 >>>> Z = G.center() >>>> Z.order() > 2
I wish I had the warm fuzzyz that come from seeing with the heart...but I don't understand this topic well (though I am learning). What is nice to see is that this agrees with this: >>> from sympy.combinatorics.generators import * >>> [w for w in dir() if 'ub' in w] ['Subs', 'rubik_cube_generators', 'subresultants', 'subsets'] >>> from sympy.combinatorics.perm_groups import * >>> G=PermutationGroup(rubik_cube_generators()) >>> G.order() 43252003274489856000L >>> Z=G.center() >>> Z.order() 2 One thing that interests me is whether there is a decomposition method for finding how a given set of permutations might produce a a given permutation, like `FooPerm.factor([P1, P2]) -> (0, 3) if FooPerm is just P2**3 or (1, 2) if P1*P2**2.` -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
