[GAP Forum] Quotient group

[Rudolf Zlabinger]

Thank you for your elegeant solution. One only should keep thereby  in mind, 
that the mapping is built by definition of the quotient group primarily 
between the cosets in G by H and the elements in the target representation 
of the quotient, not between the representatives of the cosets  and the 
target elements themselves.

best regards, Rudolf Zlabinger


----- Original Message ----- 
From: "Laurent Bartholdi" <laurent.bartholdi at gmail.com>
To: "Rudolf Zlabinger" <Rudolf.Zlabinger at chello.at>
Cc: "D N" <dn2447 at yahoo.com>
Sent: Thursday, October 26, 2006 8:11 AM
Subject: Re: [GAP Forum] Quotient group


> gap> rimage:=Random(image);; # choose a random elm of G/H, say our x
> gap> pre:=PreImages(nhom,rimage); # this is our u(x), you have to use
> PreImages because the mapping is not unique by group elements
> RightCoset(Group( [ (2,3,4), (1,2,3) ] ),(5,7)(6,8))

maybe here you are interested in:

gap> pre:=PreImagesRepresentative(nhom,rimage);
(5,7)(6,8)
gap>pre^nhom = rimage;
true

-- 
Laurent Bartholdi          \  laurent.bartholdi<at>gmail<dot>com
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