Re: mfatkineigenvalues

On Fri, 5 Oct 2018 at 12:44, Karim Belabas <Karim.Belabas@math.u-bordeaux.fr> wrote:

* J E Cremona [2018-10-05 13:41]:
> If I call mfatkineigenvalues(mf,Q) where mf is a newspace output by
> mfinit(NK,0) for some NK with trivial character, then -- as far as I can
> tell from the documentation -- mfatkineigenvalues must compute the
> splitting of mf into Galois orbits. But if I have already computed that
> splitting (e.g. using mffields, or mfsplit) then that seems very wasteful.
>
> Would it be possible to design mfatkineigenvalues() so that (optionally)
> one could give the splitting information to it?

Already done: when the splitting is done it is automagically added to
the mf struct (same mechanism as for elliptic curves).

Ah, I was wondering if calling functions with mf as a parameter had some side-effect like that.

> Secondly (different but related): again in trivial character, it would be
> useful to have a function mfatkinmat() like mfheckemat().

mfatkininit provides it (in a slightly awkward way, but it handles
arbitrary characters...)

I'll check that out. Thanks a lot,

John

Cheers,

K.B.
--
Karim Belabas, IMB (UMR 5251) Tel: (+33) (0)5 40 00 26 17
Universite de Bordeaux Fax: (+33) (0)5 40 00 21 23
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`

Prof J E Cremona
Warwick Mathematics Institute
University of Warwick
http://www2.warwick.ac.uk/fac/sci/maths/people/staff/john_cremona/