#13163: E.minimal_model() crashes with large coefficients.
-------------------------------+--------------------------------------------
Reporter: weigandt | Owner: cremona
Type: defect | Status: new
Priority: major | Milestone: sage-5.2
Component: elliptic curves | Keywords: minimal model
Work issues: | Report Upstream: N/A
Reviewers: | Authors:
Merged in: | Dependencies:
Stopgaps: |
-------------------------------+--------------------------------------------
This code
{{{
E=EllipticCurve([4382696457564794691603442338788106497, 28, 3992,
16777216, 298])
E.minimal_model()
}}}
Spits out this error:
{{{
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "_sage_input_23.py", line 10, in <module>
exec compile(u'open("___code___.py","w").write("# -*- coding: utf-8
-*-\\n" +
_support_.preparse_worksheet_cell(base64.b64decode("RT1FbGxpcHRpY0N1cnZlKFs0MzgyNjk2NDU3NTY0Nzk0NjkxNjAzNDQyMzM4Nzg4MTA2NDk3LCAyOCwgMzk5MiwgMTY3NzcyMTYsIDI5OF0pCkUubWluaW1hbF9tb2RlbCgp"),globals())+"\\n");
execfile(os.path.abspath("___code___.py"))
File "", line 1, in <module>
File "/tmp/tmpQWTtgb/___code___.py", line 4, in <module>
exec compile(u'E.minimal_model()
File "", line 1, in <module>
File
"/sagenb/sage_install/sage-5.0-boxen-x86_64-Linux/local/lib/python2.7
/site-packages/sage/schemes/elliptic_curves/ell_rational_field.py", line
2552, in minimal_model
F = self.pari_mincurve()
File
"/sagenb/sage_install/sage-5.0-boxen-x86_64-Linux/local/lib/python2.7
/site-packages/sage/schemes/elliptic_curves/ell_rational_field.py", line
713, in pari_mincurve
e = self.pari_curve(prec)
File
"/sagenb/sage_install/sage-5.0-boxen-x86_64-Linux/local/lib/python2.7
/site-packages/sage/schemes/elliptic_curves/ell_rational_field.py", line
664, in pari_curve
self._pari_curve[prec] =
pari(list(self.a_invariants())).ellinit(precision=prec)
File "gen.pyx", line 10416, in sage.libs.pari.gen._pari_trap
(sage/libs/pari/gen.c:49843)
sage.libs.pari.gen.PariError: precision too low (10)
}}}
It looks like the precision needs to be increased when such a large curve
is fed to PARI's minimal model algorithm.
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/13163>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en.
