#4964: [with patch, with review, needs work] Add Weil pairing to Sage
-------------------------------------+--------------------------------------
Reporter: dmhansen | Owner: mollerhansen
Type: enhancement | Status: reopened
Priority: minor | Milestone: sage-3.3
Component: algebraic geometry | Resolution:
Keywords: pairing, elliptic curve |
-------------------------------------+--------------------------------------
Changes (by cremona):
* summary: [with patch, needs review] Add Weil pairing to Sage => [with
patch, with review, needs work] Add Weil
pairing to Sage
Comment:
I succesfully applied the patch to 3.3.alpha3 and the doctests pass. But
the first example I tried crashed:
{{{
sage: F.<a>=GF(19^4)
sage: E=EllipticCurve(F,[-1,0])
sage: P,Q=E.gens()
sage: P.order(), Q.order()
(360, 360)
# Check that P and Q really are independent:
sage: linear_relation(P,Q,'+')
(0, 360)
sage: P.weil_pairing(Q,360)
---------------------------------------------------------------------------
PariError Traceback (most recent call
last)
...
PariError: impossible inverse modulo: (36)
}}}
So pari (which does the underlying field arithmetic) has tried to divide
by zero.
The comments in the code suggest that (1) run-time errors only happen when
the points are independent, and (2) these are caught. So here is a
counterexample to both.
Is there a typo in the code perhaps?
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/4964#comment:8>
Sage <http://sagemath.org/>
Sage - Open Source Mathematical Software: Building the Car Instead of
Reinventing the Wheel
--~--~---------~--~----~------------~-------~--~----~
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
-~----------~----~----~----~------~----~------~--~---
