Re: nfgaloisconj

[Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>]

On Tue, Jul 30, 2019 at 10:44:45AM +0900, macsyma wrote:
> Thank you, Bill.
> 
> > what it does
> 
> In my code, G1 is a permutation representation, G2 is a polynomial
> representation of G the Galois group of f over Q. The principle is
> directly linked to Q-automorphism, that for each m_j in G, the
> permutation of the roots of f is obtained by replacing alpha the
> primitive element in the root representation of f with m_j(alpha) the
> image of alpha that is a root of g. One can consider alpha =
> polroots(g)[1], m_j(alpha) = polroots(g)[i] in G12 code. 

Could you tell me why you replaced

K=lindep(concat(x,R)); K = K[2..-1]/-K[1];

by

K=matinverseimage(matconcat(vector(d,i,subst(R,v,i))~),[1..d]~);

?

Cheers,
Bill.