Hi William, I think "DirectProduct" is your friend:
gap> H:=Group((1,2,3)); Group([ (1,2,3) ]) gap> K:=Group((1,2,4)); Group([ (1,2,4) ]) gap> DirectProduct(H,K); Group([ (1,2,3), (4,5,6) ]) Ivo. Am 18.04.2012 um 14:49 schrieb William DeMeo: > Dear Forum, > > If I have two subgroups H and K of a group G, what's the best way to > form what I think is sometimes called the "complex product"? That is, > I want to form the set > > HK = { hk : h in H, k in K } > > (I don't want the group generated by H and K.) > > Below is a listing of the obvious/dumb algorithm, but I suspect > there's a better way to do this in GAP. If someone knows of one, > please let me know. > > Thanks! > -William > > > HK:=[]; > for h in H do > for k in K do > if h*k not in HK then > Add(HK,h*k); > fi; > od; > od; > > _______________________________________________ > 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