Dear Gap-Forum, On Jun 26, 2014, at 6/26/14 11:10, Pierre-Alain BOURDIL <pabou...@laas.fr> wrote:
> Suppose the following groups and ActionHomomorphisms : > gap> G:=Group((1,2)); > > gap> H := Group((3,4)); > > gap> hom := ActionHomomorphism(G,[[1,3],[2,4]],OnSets); > > gap> hom2 := ActionHomomorphism(H,[[1,3],[2,4]],OnSets); Neither of these are action homomorphisms, as the domain is not closed under the group (e.g. [2,3] is not in). We will improve the sanity tests for future versions so that an error message will be given instead of a wrong result. Regards, Alexander Hulpke > > Asking for Image(hom), i get : > gap> Image(hom); > Group([ (1,2) ]) > > But when i try Image(hom2), i get : > gap> Image(hom2); > Group([ () ]) > > > I can't figure out why the image of hom2 is an empty group, i expect a S_2 > group for both homomorphism. Is anyone here can explain this ? > > + > > -- > Pierre-Alain BOURDIL > pabou...@laas.fr <mailto:pabou...@laas.fr> > pierre-alain.bour...@fr.thalesgroup.com > <mailto:pierre-alain.bour...@fr.thalesgroup.com> > _______________________________________________ > Forum mailing list > Forum@mail.gap-system.org > http://mail.gap-system.org/mailman/listinfo/forum _______________________________________________ Forum mailing list Forum@mail.gap-system.org http://mail.gap-system.org/mailman/listinfo/forum
