plot() Overflow error int to large to convert to C long
The following code
p = 2^256 - 2^32 - 2^9 - 2^8 - 2^7 - 2^6 - 2^4 - 1
E = EllipticCurve(GF(p), [0,0,0,0,7])
plot(E)produces the following error:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "_sage_input_54.py", line 10, in <module>
exec compile(u'open("___code___.py","w").write("# -*- coding: utf-8 -*-\\n" + _support_.preparse_worksheet_cell(base64.b64decode("cGxvdChFKQ=="),globals())+"\\n"); execfile(os.path.abspath("___code___.py"))
File "", line 1, in <module>
File "/tmp/tmp1ZsAfB/___code___.py", line 2, in <module>
exec compile(u'plot(E)
File "", line 1, in <module>
File "/opt/SageMath/local/lib/python2.7/site-packages/sage/misc/decorators.py", line 564, in wrapper
return func(*args, **options)
File "/opt/SageMath/local/lib/python2.7/site-packages/sage/plot/plot.py", line 1930, in plot
G = funcs.plot(*args, **original_opts)
File "/opt/SageMath/local/lib/python2.7/site-packages/sage/schemes/elliptic_curves/ell_finite_field.py", line 113, in plot
G += plot.points([P[0:2] for P in self.points() if not P.is_zero()], *args, **kwds)
File "/opt/SageMath/local/lib/python2.7/site-packages/sage/schemes/elliptic_curves/ell_finite_field.py", line 214, in points
v = self._points_via_group_structure()
File "/opt/SageMath/local/lib/python2.7/site-packages/sage/schemes/elliptic_curves/ell_finite_field.py", line 156, in _points_via_group_structure
for m in range(1,ni[0]):
OverflowError: Python int too large to convert to C long
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Looks like a bug. Would be good to have a better-formatted traceback though.
@Iguananaut -- traceback is now formatted properly.
As a curiosity i tried
plot( EllipticCurve(GF(2017), [0,0,0,0,7]) )and the picture was a "blur", where i could not even figure out the symmetry immediately. (Or if there are more then 2017 points.) But the picture convinced me that all the points were computed, than shown somehow (by mappingGF(2017)on the axes).Then i tried
plot( EllipticCurve(GF((2^30).next_prime()), [0,0,0,0,7]) )and i would have been glad to get the OverflowError, instead, the machine really started again seriously to compute all the points, and i lost control. There was no chance to start a terminal in the next minutes, to get the process, and kill it.So which should be the reason / the sense for getting some "statistical picture" for such a big prime, as the posted one?