Thanks Georg, my memory is not what it used to be! I just hate to see this error recurring apparantly in something I wrote....
John On 19 Feb, 11:29, "Georg S. Weber" <georgswe...@googlemail.com> wrote: > > Can William or someone who gets this error (I don't!) test what > > happens if you replace > > > G=E.change_ring(GF(p)).abelian_group() > > > by > > > N=E.change_ring(GF(p)).cardinality() > > > ? The cardinality will be provided by pari, so if it is a pari > > problem that should still cause a problem. The abelian group code is > > mine, so I would expect that is more likely to be the issue (!) We > > used to have a function abelian_group_prime_field() which only worked > > over prime fields and used pari, which was deleted at some point, but > > in fact that function just called a gp script of mine so was not > > really inedpendent. > > > Secondly, add "debug=True" to the abelian_group() call and send me the > > output. > > > John > > Hi John, > I can reproduce this bug 100%, and some time ago you and I (the thread > should be findable, I didn't search thoroughly) already went together > through this topic with the following result (it's all written down in > #4181): > The bug is triggered by: > > sage: for p in prime_range(31300, 32600): EllipticCurve(GF(p), > [0,1,1,10,13]) > > The bug is *not* triggered by (although the prime range is more than > an order of magnitude larger!): > > sage: for p in prime_range(32768, 100000): EllipticCurve(GF(p), > [0,1,1,10,13]) > > So it seems very unlikely that the root cause is anything in > "arithmetic" parts of the code. > It is something very strange and deeply buried in the system, somehow > memory allocation / heap / whatever related. My thought back then was, > that it must be something with 16-Bit signed integers on Mac OS X / 32 > Bit. > > I'll investigate further as soon as I have access to a system with a > Sage install again. > > Cheers, > gsw --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
