> < ^ Date: Wed, 01 Sep 1993 12:29:43 +0200
> < ^ From: Frank Celler <frank.celler@math.rwth-aachen.de >
< ^ Subject: Re: Calculating Invariants

Dear Forum,
some letter to the forum where rejected by our list-server, because
they were sent from different accounts than usual.

sorry for any delay

Date: Tue, 24 Aug 1993 13:55:31 +0200
Comment: GAP Forum
Originator: gap-forum@samson.math.rwth-aachen.de
Errors-To: martin@samson
Reply-To: <gap-forum@samson>
Sender: gap-forum@samson
Version: 5.31 -- Copyright (c) 1991, Anastasios Kotsikonas
From: gap-forum@samson
To: martin@samson
Subject: Re:  Calculating Invariants

I might have two (!) answers for Mr Donaghy's request; both are programs
written in Maple. They calculate the ring of invariants of a finite
linear group defined over K=Q . In other words, the group acts on the
indeterminates of a purely transcendental extension of K by linear
transformations. "Calculate" means that they calculate a Cohen-Macaulay
basis for the ring of invariants.

The first program has been written by Janet McShane together with
Larry Grove, whom Herr Neubueser already mentioned in his reply (email

The second one is by me. It has been published in the Maple Share
Library and can be obtained by anonymous ftp on
neptune.inf.ethz.ch (,
but also directly from me by email. In my program you can also take an
algebraic number field for K, and it can calculate syzygies between the
generating invariants.

Hope I won't get kicked out of the forum for advertising Maple programs!

Gregor Kemper

> < [top]