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Dear Mrs. and Mr. Forum,

Peter Mueller writes

if I understand the documentation correctly, then a command like

`GeneralLinearGroup(Permutations,2,2)'

should return the the group GL(2,2) as a permutation group (hopefully

in the natural representation, though that's not specified there).

He reports that in GAP3R4P2 this does not work.

The reason for this bug is that in spite of the promises in the manual

section 'The Basic Groups Library' nobody wrote the corresponding code.

The next upgrade will fix this, for general linear groups as well as for

special linear and symplectic groups, and general/special unitary groups.

For the moment, the following function should suffice.

GeneralLinearPermGroup := function( n, q )

local matgrp, # the desired group as matrix group

space, # natural vector space 'matgrp' acts on

vectors; # set of nonzero vectors in 'space'

matgrp:= GeneralLinearMatGroup( n, q );

space:= GF(q)^n;

vectors:= Elements( space );

RemoveSet( vectors, Zero( space ) );

return Operation( matgrp, vectors );

end;

Kind regards

Thomas Breuer

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