That sounds quite reasonable. I try to read the code again and search a
solution. Thank you very much.
On Thursday, February 28, 2013 2:05:07 PM UTC+1, David Loeffler wrote:
>
> The bug also occurs on Sage 5.7, and a quick-and-dirty bisection
> script shows that n = 46341 does work and n = 46342 does not. Since
> 46341 is almost exactly the square root of 2^{31}, and the relevant
> bits of code seem to use C int variables rather than Sage integers
> (presumably for speed reasons), it looks like an integer overflow.
>
> David
>
> On 27 February 2013 17:17, John Cremona <john.c...@gmail.com <javascript:>>
> wrote:
> > Try asking Bosman directly; I don't know if he reads this list.
> >
> > John
> >
> > On 27 February 2013 15:23, Peng <tianpen...@gmail.com <javascript:>>
> wrote:
> >> Dear John Cremona,
> >> Thanks for your reply.
> >>
> >> For n=45000 or smaller, it works well and gives an output. Then the
> next
> >> number I tried is 50000 and this gave an Error.
> >>
> >> In sage 5.7, this doesn't work neither.
> >>
> >> I even don't know yet why this happens exactly.
> >>
> >> PS:
> >> I'm trying to compute the modular Galois represtations of Ramanujan tau
> >> function using the algorithm by Johan Bosman, which requests a huge
> >> precision for q-expansion of modular forms used inside the code.
> Actually,
> >> this error happens when I ran Bosman's code and sage indicates that
> >> HeilbronnMere went wrong in this case.
> >>
> >>
> >>
> >> On Wednesday, February 27, 2013 2:26:55 PM UTC+1, John Cremona wrote:
> >>>
> >>> I cannot think of a reason for computing Heilbronn matrices of such
> >>> large index, so you have one? And how does it perform for smaller n,
> >>> say 1000, 10000, 20000, ...?
> >>>
> >>> Lastly, Sage-5.7 has been released so you should upgrade (but I am not
> >>> saying if any relevant code has changed between 5.4.1 and 5.7, as I
> >>> have not checked).
> >>>
> >>> John
> >>>
> >>> On 27 February 2013 11:32, Peng <tianpen...@gmail.com> wrote:
> >>> > Dear all,
> >>> >
> >>> > I've tried to compute Heilbronn Matrices for n=50000 in sage 5.4.1,
> but
> >>> > the
> >>> > following Error comes out when I run
> >>> >
> >>> > sage: H=HeilbronnMerel(50000)
> >>> >
> >>> > --------------------------------------------------------------------
> >>> >
> >>> > RuntimeError Traceback (most recent call last)
> >>> >
> >>> > /home/guests/sage-5.4.1/<ipython console=""> in <module>()
> >>> >
> >>> >
> >>> >
> /home/guests/sage-5.4.1/local/lib/python2.7/site-packages/sage/modular/modsym/heilbronn.so
>
>
> >>> > in sage.modular.modsym.heilbronn.HeilbronnMerel.__init__
> >>> > (sage/modular/modsym/heilbronn.c:5185)()
> >>> >
> >>> >
> >>> >
> /home/guests/sage-5.4.1/local/lib/python2.7/site-packages/sage/modular/modsym/heilbronn.so
>
>
> >>> > in sage.modular.modsym.heilbronn.HeilbronnMerel._initialize_list
> >>> > (sage/modular/modsym/heilbronn.c:5343)()
> >>> >
> >>> > RuntimeError: Floating point exception
> >>> >
> >>> > --------------------------------------------------------------------
> >>> >
> >>> > It seems to be a bug in sage when computing Heilbronn Matrices for
> large
> >>> > n.
> >>> > However, I even couldn't find out why this happens. Anybody can
> please
> >>> > help
> >>> > me handle with that? Thank you.
> >>> >
> >>> >
> >>> > Best regards!
> >>> >
> >>> > --
> >>> > You received this message because you are subscribed to the Google
> >>> > Groups
> >>> > "sage-devel" group.
> >>> > To unsubscribe from this group and stop receiving emails from it,
> send
> >>> > an
> >>> > email to sage-devel+...@googlegroups.com.
> >>> > To post to this group, send email to sage-...@googlegroups.com.
> >>> > Visit this group at http://groups.google.com/group/sage-devel?hl=en.
>
> >>> > For more options, visit https://groups.google.com/groups/opt_out.
> >>> >
> >>> >
> >>
> >> --
> >> You received this message because you are subscribed to the Google
> Groups
> >> "sage-devel" group.
> >> To unsubscribe from this group and stop receiving emails from it, send
> an
> >> email to sage-devel+...@googlegroups.com <javascript:>.
> >> To post to this group, send email to
> >> sage-...@googlegroups.com<javascript:>.
>
> >> Visit this group at http://groups.google.com/group/sage-devel?hl=en.
> >> For more options, visit https://groups.google.com/groups/opt_out.
> >>
> >>
> >
> > --
> > You received this message because you are subscribed to the Google
> Groups "sage-devel" group.
> > To unsubscribe from this group and stop receiving emails from it, send
> an email to sage-devel+...@googlegroups.com <javascript:>.
> > To post to this group, send email to
> > sage-...@googlegroups.com<javascript:>.
>
> > Visit this group at http://groups.google.com/group/sage-devel?hl=en.
> > For more options, visit https://groups.google.com/groups/opt_out.
> >
> >
> >
>
--
You received this message because you are subscribed to the Google Groups
"sage-devel" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to sage-devel+unsubscr...@googlegroups.com.
To post to this group, send email to sage-devel@googlegroups.com.
Visit this group at http://groups.google.com/group/sage-devel?hl=en.
For more options, visit https://groups.google.com/groups/opt_out.
