Artin Representations in MAGMA

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Here's a toy example of the difficulty I'm having...


Let $K/\mathbb{Q}$ be a Galois extension of degree 3.

There are two non-trivial irreducible characters on Gal$(K/\mathbb{Q}),$ call them $\chi_1$ and $\chi_2.$

Once I've defined the number field $K$ in MAGMA, I can get these as follows:

triv, chi1, chi2 := Explode(ArtinRepresentations(K));

Now I list the elements of the Galois group of the extension:

id, phi1, phi2 := Automorphisms(K);

What I want to do now is something like "Evaluate(chi1,phi1)" but this doesn't exist...


Does anyone know how to go about this?

Many thanks!

EDIT: Here is some sample code:

_<x>:=PolynomialRing(Rationals()); K:=Subfields(CyclotomicField(9))[3,1]; triv,chi1,chi2:=Explode(ArtinRepresentations(K)); id,phi1,phi2:=Explode(Automorphisms(K)); chi1(phi1);