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LMFDB / lmfdb

L-Functions and Modular Forms Database
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Feature request: add infinite-order Mordell-Weil generators as columns in Elliptic Curve search results #5836

Open alonamit1729 opened 6 months ago

alonamit1729 commented 6 months ago

When searching for elliptic curves it is currently not possible to include the Mordell-Weil generators as columns in the search results. It may be cumbersome to do so for curves of high rank, but for rank 1 (and possibly 2, 3) it would be extremely valuable to include them.

edgarcosta commented 6 months ago

This is doable. However, it is not straightforward, as MW generators live in a different table from the search table.

roed314 commented 6 months ago

The main problem is with downloading, if we're getting the data from another table.

edgarcosta commented 6 months ago

I agree, another not straightforward point :)

alonamit1729 commented 6 months ago

I should have mentioned that downloading is my main motivation :) I hope a join is possible!

roed314 commented 6 months ago

Ah. Yeah, I didn't get downloading to work. If you set up the LMFDB locally, you can do the following:

from lmfdb import db
D = {rec["lmfdb_label"]:rec["gens"] for rec in db.ec_mwbsd.search({}, ["lmfdb_label", "gens"])}

This gives you a dictionary with all the generators for all the curves in the LMFDB, and takes about 3.5 minutes to run.

JohnCremona commented 1 month ago

In case it is helpful, the repositories https://github.com/JohnCremona/ecdata and https://github.com/JohnCremona/ecnf-data have the raw data as well as Sage code for reading the files. Also, the web page https://johncremona.github.io/ecdata/ (which long predates the LMFDB) allows you to download all the generators in text files called allgens.* split into conductor ranges of 10000.

Of course it really should be true that anything you can do with these files you can also do with the LMFDB.