Thanks, Robert.  I am well advanced with testing this now.  I changed 3 files:

1.      ~/sage-2.7/data/extcode/pari/simon/ellQ.gp
where I changed one function main() to have an extra parameter

2.      ~/sage-2.7/devel/sage-main/sage/schemes/elliptic_curves/gp_simon.py
which is the associated wrapper, and

3.      
~/sage-2.7/devel/sage-main/sage/schemes/elliptic_curves/ell_rational_field.py
so that the member function simon_two_descent() for EllipticCurve also
has the new parameter.  I edited the documentation part of 3
accordingly, and am now trying to find the example which failed
before...

John

On 8/8/07, Robert Bradshaw <[EMAIL PROTECTED]> wrote:
>
> On Aug 8, 2007, at 4:28 AM, John Cremona wrote:
>
> > I am using the simon_two_descent() method for EllipticCurve(), and
> > have some curves where the default pari precision is in sufficient,
> > for example
> >
> >
> > e=EllipticCurve([0,0,0,-10164,409444]);
> > e.simon_two_descent()
> >
> > fails withe the (gp) run-time error "  *** bnfsunit: precision too low
> > in get_arch."
> >
> > Now in a normal gp session I can fix this after either
> > \p56
> > or
> > default(realprecision, 56)
> >
> > but when running in sage, doing
> > pari.set_real_precision(120)
> > seems to have no effect.
> >
> > I guess this is because the latter call effects the precision of the
> > pari library functions, whereas simon_two_descent() is a gp script.
>
> Yes, this is correct. Gp scripts run in their own "clean" session of
> pari so that previous commands/etc. won't (adversely or not) affect
> their behavior.
>
> > If this is the case, and there is no better method, I guess we could
> > add an extra input parameter "prec" to the simon_two_descent()
> > function and then in that function call default(realprecision,prec).
> > The default would be 28.
>
> Sounds good to me.
>
> > I should be capable of doing this myself!  But
>
> That would be great.
>
> > (1) I'm not sure which file to edit: looks like
> > /home/jec/sage-2.7/devel/sage-main/build/sage/schemes/
> > elliptic_curves/gp_simon.py
> > but there is at least one other clone of that file;
>
> This is the one, where was the other one you were looking at?
>
> > (2) What should I do then to rebuild sage and test it?
>
> sage -b rebuilds. To add a test to the doctests, add an example
> (preferably one that you fixed) to the area surrounded by triple
> quotes at the top of the relevant function. This example will then be
> tested before every release of SAGE to make sure it still works
> correctly.
>
> > (3) When I am happy that it works, exactly what should I do to upload
> > the change to that it gets incorporated into sage?
>
> SAGE uses the mercurial revision control system. http://
> www.selenic.com/mercurial/wiki/ When you are happy with your changes,
> you can (from the sage prompt) type
>
> sage: hg_sage.commit()
>
> which will bring up an editor where you comment on your changes, then
> it will check them in. To send those changes to someone else (e.g.
> William) do
>
> sage: hg_sage.bundle(name_of_file)
>
> and send the resulting .hg file via email. There are lots of other
> commands, e.g. hg_sage.diff() to see what you changed, etc.
>
> This should be enough to get you going, but I would reccoment taking
> a look at http://modular.math.washington.edu/sage/doc/html/prog/
> prog.html , specifically section 7.
>
> > If this is documented, someone please point me in the right direction.
> >  By the way, whoever it was who did the "SAGE search" thing deserves a
> > prize -- it is permanently in my firefox top right corner and is how I
> > look up anything about SAGE now!
> >
> > John
> >
> > PS I also have some fixes for the mwrank C++ code which I should
> > upload, so the answers to my questions above should ideally answer
> > that too.
> >
> >
> > --
> > John Cremona
> >
> >
>
> >
>


-- 
John Cremona

--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at http://groups.google.com/group/sage-devel
URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/
-~----------~----~----~----~------~----~------~--~---

Reply via email to