|Bill Allombert on Sat, 20 Dec 2008 16:39:50 +0100|
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|Re: Functions elllderiv and ellanalyticrank|
On Sat, Dec 20, 2008 at 10:16:23AM +0100, Karim Belabas wrote: > * Bill Allombert [2008-12-19 23:20]: > > On Fri, Dec 19, 2008 at 07:20:53PM +0100, Karim Belabas wrote: > > > > 2) I think elllderiv should be renamed ellL1 for consistency with bnrL1 > > > > (and maybe add a flag so that both functions have the same semantic). > > Had forgotten to commit this one, sorry. No flag added: contrary to bnrL1, we > compute the value at the center of the critical strip, so no symmetry > in the special value here. I'd like to clarify something: Is it correct that bnrL1 returns L^(r)(0, chi)/r! and ellL1 returns L^(r)(1)? The 1/r! missing factor is slighly inconsistent. However the functions are already sufficiently differents so that it might not matter to much. > > 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. > > I just checked the first curves for each rank <=7, and it worked fine. > > For the rank 7, and curve [0,1,0,-5945,583879], we get: > > > > %3 = [7, 10410274.011880989226208667596394924308] > > *** last result computed in 32mn, 22,973 ms. > > Yes, point A) has recently been fixed. Actually I think I ran it with 2GB of stack before this fix. ... 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] ? ## *** last result computed in 2,248 ms. ? \p100 realprecision = 115 significant digits (100 digits displayed) ? ellanalyticrank(ellinit([0, 0, 0, -5187, 176830])) %103 = [1, -5.325940321646741761873678862473973257966395825229515552647757138732472557105569149428617123587867198 E-5] ? ## *** last result computed in 23,654 ms. ? \p300 realprecision = 308 significant digits (300 digits displayed) ? ellanalyticrank(ellinit([0, 0, 0, -5187, 176830])) %104 = [1, 1.03109774801654317703165538440292385425270140765489094906701694740003883225307680175789397957995636774656436968392004550456741982003305244178599175383191237909663561224188478459850675217896796053901785562987093216560935193453313209662350084597201356139829756733116552495511875367665860023212578851892 E-19] ? ## *** last result computed in 6mn, 45,577 ms. Clearly the value L'(1) is worng (independently of the rank of the curve). Cheers, Bill.