#11800: Problem with points at infinity in hyperelliptic curves
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   Reporter:  gaudry              |          Owner:  AlexGhitza                 
              
       Type:  defect              |         Status:  needs_work                 
              
   Priority:  minor               |      Milestone:  sage-5.0                   
              
  Component:  algebraic geometry  |       Keywords:  ecc2011, sd35, 
hyperelliptic curve, conic
Work_issues:                      |       Upstream:  N/A                        
              
   Reviewer:  Marco Streng        |         Author:  David Eklund               
              
     Merged:                      |   Dependencies:  #11930                     
              
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Comment(by davideklund):

 In the present patch, the points() method returns all the rational points
 on the plane projective model, including those on the line at infinity.

 I agree that when the projective plane model is singular (the typical
 case) we really want the points() method to spit out points on a smooth
 model. Maybe the issue should be raised in a separate ticket. A comment on
 the matter by David Kohel:

 The approach of Magma is to use weighted projective space which allows one
 to represent two points at infinity (when the degree of {{{f + h^2/4}}} is
 even). In this case one gets two points at infinity rather than one
 (singular when g > 0).

-- 
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/11800#comment:16>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica, 
and MATLAB

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