> < ^ Date: Wed, 05 Sep 2001 09:18:08 +0200 (MET DST)
> < ^ From: Jan Draisma <Jan.Draisma@unibas.ch >
> < ^ Subject: Re: Requesting help

Dea Gap-forum, and Chad,

you asked:
> I am interested in working with groups formed by crossing two integer sets.
> For example: Z2 X Z2 = { (0,0), (0,1), (1,0), (1,1)} I am a new user to GAP
> and have looked in the tutorial and the REF files under groups but have
> found nothing. Does anyone know how to do this or can you point me in the
> right direction of where I might look to find out how? Thank you for any
> help you can provide.

If you want to see Z2xZ2 as a group, you can enter:

gap> G:=DirectProduct(CyclicGroup(2),CyclicGroup(2));
<pc group of size 4 with 2 generators>
gap> gens:=GeneratorsOfGroup(G);
[ f1, f2 ]
gap> gens[1]*gens[2];
gap> gens[1]*gens[2]*gens[1];

If you want to see it as an algebra over Z2:
gap> R:=DirectSumOfAlgebras(GF(2),GF(2));
<algebra of dimension 2 over GF(2)>

It should be possible to construct it as a ring (in a way that you can
also treat Z2xZ3 as a ring).

Best wishes,


Miles-Receive-Header: reply

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