I'll fix this as it is my code.

Note that this curve has j=0 and the cases of j=0, 1728 were not
implemented with any efficiency (or, it seems correctness), but that I
am half-way through doing that.

In the meantime I'll try to put in a quick patch to correct what's
wrong here.  First step, I'll open a ticket.

John Cremona

On 07/04/2008, William Stein <[EMAIL PROTECTED]> wrote:
>
>  An elliptic curve bug report from a student of Koblitz...
>
>
>  ---------- Forwarded message ----------
>  From:  <[EMAIL PROTECTED]>
>  Date: Mon, Apr 7, 2008 at 12:39 PM
>  Subject: elliptic curve trace problem in SAGE
>  To: [EMAIL PROTECTED]
>
>
>  William,
>      While working on some things, I found a bug in SAGE:
>
>   sage:k.<a>=GF(3^5)
>
>   sage:E=EllipticCurve(k,[-1,-1])
>
>   sage:E.trace_of_frobenius()
>   0
>
>   This isn't correct.  It should be -27.  I also discovered you can get
>  around it.
>
>   sage:E.cardinality_exhaustive()
>   271
>
>   sage:E.trace_of_frobenius()
>   -27
>
>   Somehow, doing .cardinality_exhaustive() fixes the bug.
>
>
>
>   Dustin Moody
>
>
>
>
>
>
>
>  --
>  William Stein
>  Associate Professor of Mathematics
>  University of Washington
>  http://wstein.org
>
>  >
>

--~--~---------~--~----~------------~-------~--~----~
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-support
URLs: http://www.sagemath.org
-~----------~----~----~----~------~----~------~--~---

Reply via email to