#18152: Universal Cyclotomic Field implementation using libgap
-------------------------------------+-------------------------------------
Reporter: vdelecroix | Owner:
Type: enhancement | Status: needs_review
Priority: major | Milestone: sage-6.7
Component: number fields | Resolution:
Keywords: | Merged in:
Authors: Vincent Delecroix | Reviewers:
Report Upstream: N/A | Work issues:
Branch: | Commit:
u/vdelecroix/18152 | e4a352468cf9c018b9bdf148a3de03793a111b9e
Dependencies: #18153 | Stopgaps:
-------------------------------------+-------------------------------------
Comment (by stumpc5):
Hi Vincent,
Replying to [comment:19 vdelecroix]:
> Me too. I wondered if something were better with your code. But except
the documentation I did not find any case were it was faster.
Did you already redo the Galois conjugate test which I remember was slower
in Gap back then?
> Great! I will add this to the `ucf_test.py` that I wrote. If you have
other examples in mind, please propose. I am not sure it will make a
difference now since big numbers with pexpect implies a lot of parsing and
computation. With libgap it is not the case anymore.
I just did
{{{
sage: a = E( 2^11 * 3^4 )
sage: %time x = a.galois_conjugates()
CPU times: user 5.52 s, sys: 159 ms, total: 5.68 s
Wall time: 5.66 s
sage: %time x = a.galois_conjugates()
CPU times: user 6.81 s, sys: 170 ms, total: 6.98 s
Wall time: 6.99 s
}}}
and compared it to
{{{
gap> a := E( 2^11 * 3^4 );;
gap> L := PrimeResidues(165888);;
gap> for i in L do
> x := GaloisCyc(a,i);
> od;
}}}
which I had running for 30 sec before I ctrc-c'ed it. (I also believe that
in Sage, a big portion of the time is spend of computing the list of
coprimes.)
> You do not remember what they are? Did you report them to Gap?
I did report them, and they were fixed.
Once I get your branch running, I try to get back other tests I did.
Cheers, Christian
--
Ticket URL: <http://trac.sagemath.org/ticket/18152#comment:20>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
