Re: Functions elllderiv and ellanalyticrank

[Bill Allombert <Bill.Allombert@math.u-bordeaux1.fr>]

On Sat, Dec 20, 2008 at 07:21:22PM +0100, Karim Belabas wrote:
> * Bill Allombert [2008-12-20 16:39]:
> > On Sat, Dec 20, 2008 at 10:16:23AM +0100, Karim Belabas wrote:
> > > * Bill Allombert [2008-12-19 23:20]:
> > > > Also the DEBUG message should be improved to be more useful.
> > > 
> > > Done to some extent, I think. More specific suggestions (svn11475 and above) ?
> > 
> > I'd like timing of each ellL1 computation done by ellanalyticrank 
> > separately.
> 
> Done.
> 
> > With \p38, ellanalytic rank fails on a large number (about 1/3 so far)
> > of rank 5 curve in Womack database (it reports rank 1 instead of 5).  
> > 
> > An example: [0, 0, 0, -5187, 176830]
> > ? \p38
> >    realprecision = 38 significant digits
> > ? ellanalyticrank(ellinit([0, 0, 0, -5187, 176830]))
> > %102 = [1, 1278372.8304848296806080373284485378614]
> [...]
> > Clearly the value L'(1) is worng (independently of the rank of the curve).
> 
> Fixed since svn-11480 (the an cache should have been initialized to 0).

Now, ellanalytic report rank 5 for all the rank 5 curves in Womack
database. Good!

One comment on ellanalyticrank():
the instances of ellL1_i could reuse the vecsmall el->ap, growing it if
necessary.

Cheers,
Bill.