Unicode issue with modular polynomials database

[kedlaya]

sage: MP = AtkinModularPolynomialDatabase()
sage: MP[3]
---------------------------------------------------------------------------
UnicodeDecodeError                        Traceback (most recent call last)
<ipython-input-29-920f2702531e> in <module>()
----> 1 MP[Integer(3)]

/home/kedlaya/sage/local/lib/python3.6/site-packages/sage/databases/db_modular_polynomials.py in __getitem__(self, level)
    156                 raise TypeError("Argument level (= %s) must be prime."%N)
    157         modpol = self._dbpath(level)
--> 158         coeff_list = _dbz_to_integer_list(modpol)
    159         if self.model == "Cls":
    160             P = PolynomialRing(IntegerRing(),2,"j")

/home/kedlaya/sage/local/lib/python3.6/site-packages/sage/databases/db_modular_polynomials.py in _dbz_to_integer_list(name)
     65     """
     66     from sage.rings.integer import Integer
---> 67     data = _dbz_to_string(name)
     68     return [[Integer(v) for v in row.strip().split(" ")]
     69             for row in data.split("\n")[:-1]]

/home/kedlaya/sage/local/lib/python3.6/site-packages/sage/databases/db_modular_polynomials.py in _dbz_to_string(name)
     41         raise LookupError("filename {} does not exist".format(filename))
     42 
---> 43     data = bz2.decompress(f.read())
     44 
     45     return data

/home/kedlaya/sage/local/lib/python3.6/codecs.py in decode(self, input, final)
    319         # decode input (taking the buffer into account)
    320         data = self.buffer + input
--> 321         (result, consumed) = self._buffer_decode(data, self.errors, final)
    322         # keep undecoded input until the next call
    323         self.buffer = data[consumed:]

UnicodeDecodeError: 'utf-8' codec can't decode byte 0x90 in position 13: invalid start byte

Component: modular forms

Author: Frédéric Chapoton

Branch/Commit: 8c80a1d

Reviewer: Kiran Kedlaya

Issue created by migration from https://trac.sagemath.org/ticket/27569

[kedlaya]

comment:2

Guessing this is a Py3 issue?

[fchapoton]

comment:3

here is a tentative of fix, plus some pep8 cleanup in the modified file

---

New commits:

f935155

trac 27569, python3 fix for modular database

[fchapoton]

Author: Frédéric Chapoton

[fchapoton]

Branch: u/chapoton/27569

[fchapoton]

Commit: f935155

[sagetrac-git]

Changed commit from f935155 to 6b745dc

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

6b745dc

trac 27569 fixing the doctests

[sagetrac-git]

Changed commit from 6b745dc to 8c80a1d

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

8c80a1d

trac 27569 fixing another doctest

[kedlaya]

comment:6

This does fix the issue on my end. But what is going on with the patchbot failures?

[fchapoton]

comment:7

patchbot looks green enough to me

[kedlaya]

comment:8

OK then!

[kedlaya]

Reviewer: Kiran Kedlaya

[vbraun]

Changed branch from u/chapoton/27569 to 8c80a1d