> < ^ Date: Fri, 11 Feb 1994 14:00:00 +0100
> < ^ From: Frank Celler <frank.celler@math.rwth-aachen.de >
< ^ Subject: Re: possible problem with Domain()

Dear Robert Beals,

Matrices.operations.MinimalPolynomial is unbound. Is there any
reason why for a rational matrix A, Domain([A]) doesn't return
FieldMatrices? (FieldMatrices.operations.MinimalPolynomial exists.)

the reason is, that we plan to use 'MatrixAlgebra( K, n )' as result of a
'Domain' call as soon as there are matrix algebras in GAP (which will be in the
near future). At the moment you should call 'MinimalPolynomial' with the
additional first parameter 'FieldMatrices' (or 'FiniteFieldMatrices' depending
on your problem).

gap> MinimalPolynomial( FieldMatrices, [ [1,2], [3,4] ] );
X(Rationals)^2 - 5*X(Rationals) - 2

The problem with this solution is that you cannot force your matrices to
be interpreted as matrices over a given field.

for a cyclotomic field F GAP seems to be unable to compute Euclidean
quotients in F[x] (that is, the ring of polynomials in x over the

there was indeed a problem in GAP 3r3, this is fixed in 3r4.

best wishes

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