The following code shows that subgroups of automorphism groups of graphs are handled wrongly:
sage: g = Graph([[1, 2, 4], []]) sage: a = g.automorphism_group() sage: print(a) Permutation Group with generators [(2,4), (1,2)] sage: print(a.commutator()) Permutation Group with generators [(1,2,3)] Note that a.commutator() moves 3 though 3 is not a vertex of the graph. Somewhat strangely, if one defines directly a = PermutationGroup([[(2, 4)], [(1, 2)]]), then a.commutator() returns the correct subgroup. By the way, it doesn't help if the n vertices of the graph consist of the list [1..n]. I have a complicated example where the automorphism group is computed correctly, but the action of the commutator subgroup is with respect to a different labeling of the vertices. -- Peter Mueller -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/sage-devel/fec1df7a-9db7-43b2-9af2-8dcdf6658585n%40googlegroups.com.
