Thanks for the suggestion, but the direct product is not my friend in this case. (In particular, the direct product is a group. HK is not always a group.) On Apr 18, 2012 3:11 AM, "Ivo Hedtke" <hed...@me.com> wrote:
> 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