Error searching for ECQ multiple of conductor

[havarddj]

Searching for "multiple of" in the conductor field (e.g. take 7) in
https://www.lmfdb.org/EllipticCurve/Q/?search_type=
gives an error:
https://www.lmfdb.org/EllipticCurve/Q/?conductor_type=multiple&conductor=7

[jenpaulhus]

This issue comes during the check for completeness of the particular search.

The feature on the ECQ pages requires $mod and that's where the error is coming from in utils/completeness.py

Traceback (most recent call last):
  File "/scratch/sage/sage-10.3/local/var/lib/sage/venv-python3.10/lib/python3.10/site-packages/flask/app.py", line 2091, in __call__
    return self.wsgi_app(environ, start_response)
  File "/scratch/home/jenpaulhus/lmfdb/lmfdb/app.py", line 42, in __call__
    return self.app(environ, start_response)
  File "/scratch/sage/sage-10.3/local/var/lib/sage/venv-python3.10/lib/python3.10/site-packages/flask/app.py", line 2076, in wsgi_app
    response = self.handle_exception(e)
  File "/scratch/sage/sage-10.3/local/var/lib/sage/venv-python3.10/lib/python3.10/site-packages/flask/app.py", line 2073, in wsgi_app
    response = self.full_dispatch_request()
  File "/scratch/sage/sage-10.3/local/var/lib/sage/venv-python3.10/lib/python3.10/site-packages/flask/app.py", line 1519, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/scratch/sage/sage-10.3/local/var/lib/sage/venv-python3.10/lib/python3.10/site-packages/flask/app.py", line 1517, in full_dispatch_request
    rv = self.dispatch_request()
  File "/scratch/sage/sage-10.3/local/var/lib/sage/venv-python3.10/lib/python3.10/site-packages/flask/app.py", line 1503, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**req.view_args)
  File "/scratch/home/jenpaulhus/lmfdb/lmfdb/elliptic_curves/elliptic_curve.py", line 93, in rational_elliptic_curves
    return elliptic_curve_search(info)
  File "/scratch/home/jenpaulhus/lmfdb/lmfdb/utils/search_wrapper.py", line 274, in __call__
    complete, msg, caveat = results_complete(table.search_table, query, table._db, info.get("search_array"))
  File "/scratch/home/jenpaulhus/lmfdb/lmfdb/utils/completeness.py", line 49, in results_complete
    return lookup[table].check(query, db, search_array)
  File "/scratch/home/jenpaulhus/lmfdb/lmfdb/utils/completeness.py", line 678, in check
    if test(db, [query[col] for col in cols]):
  File "/scratch/home/jenpaulhus/lmfdb/lmfdb/utils/completeness.py", line 703, in __call__
    return all(self.cls(D).is_subset(B) for D, B in zip(Ds, self.bounds))
  File "/scratch/home/jenpaulhus/lmfdb/lmfdb/utils/completeness.py", line 703, in <genexpr>
    return all(self.cls(D).is_subset(B) for D, B in zip(Ds, self.bounds))
  File "/scratch/home/jenpaulhus/lmfdb/lmfdb/utils/completeness.py", line 438, in __init__
    self.rset = integer_normalize(to_rset(x))
  File "/scratch/home/jenpaulhus/lmfdb/lmfdb/utils/completeness.py", line 159, in to_rset
    raise ValueError(f"Unsupported key {k}")
ValueError: Unsupported key $mod

[jenpaulhus]

Someone also just reported this on the bugreport so I'm adding the production issue label.

[rvisser7]

As @jenpaulhus mentioned, it seems it's just a matter of updating to_rset() in the utils/completeness.py file to allow for the $mod keyword. Probably the simplest fix is just to add:

elif k == "$mod":
    pass

between lines 157 and 158 in utils/completeness.py. i.e. we just pretend there's no completeness constraint if the users searches for "multiple of". The ideal solution would be to intersect ans with all multiples of the user-given conductor, though this requires constructing an instance of RealSet which is an infinite union of points, which I'm not sure if this is possible ?

I can submit a PR implementing the above fix, if it's an urgent issue? But probably @roed314 would know what the best fix is :)

[edgarcosta]

Another one:

Exception on /ModularForm/GL2/Q/holomorphic/ [GET]
Traceback (most recent call last):
  File "/home/sage/sage-10.5/local/var/lib/sage/venv-python3.12/lib/python3.12/site-packages/flask/app.py", line 1511, in wsgi_app
    response = self.full_dispatch_request()
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sage/sage-10.5/local/var/lib/sage/venv-python3.12/lib/python3.12/site-packages/flask/app.py", line 919, in full_dispatch_request
    rv = self.handle_user_exception(e)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sage/sage-10.5/local/var/lib/sage/venv-python3.12/lib/python3.12/site-packages/flask/app.py", line 917, in full_dispatch_request
    rv = self.dispatch_request()
         ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sage/sage-10.5/local/var/lib/sage/venv-python3.12/lib/python3.12/site-packages/flask/app.py", line 902, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)  # type: ignore[no-any-return]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/lmfdb/lmfdb-git-web/lmfdb/classical_modular_forms/main.py", line 172, in index
    return newform_search(info)
           ^^^^^^^^^^^^^^^^^^^^
  File "/home/lmfdb/lmfdb-git-web/lmfdb/utils/search_wrapper.py", line 274, in __call__
    complete, msg, caveat = results_complete(table.search_table, query, table._db, info.get("search_array"))
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/lmfdb/lmfdb-git-web/lmfdb/utils/completeness.py", line 49, in results_complete
    return lookup[table].check(query, db, search_array)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/lmfdb/lmfdb-git-web/lmfdb/utils/completeness.py", line 673, in check
    fill(query)
  File "/home/lmfdb/lmfdb-git-web/lmfdb/utils/completeness.py", line 819, in __call__
    query["Nk2"] = C(N) * C(k) * C(k)
                   ^^^^
  File "/home/lmfdb/lmfdb-git-web/lmfdb/utils/completeness.py", line 438, in __init__
    self.rset = integer_normalize(to_rset(x))
                                  ^^^^^^^^^^
  File "/home/lmfdb/lmfdb-git-web/lmfdb/utils/completeness.py", line 159, in to_rset
    raise ValueError(f"Unsupported key {k}")
ValueError: Unsupported key $mod
[2026-02-02 00:23:51 UTC] 500 error on URL https://www.lmfdb.org/ModularForm/GL2/Q/holomorphic/?level_type=multiple&level=23&weight=1 ()

as reported by @lewismcombes