#18454: New `random_cone()` function
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       Reporter:  mjo                |        Owner:
           Type:  enhancement        |       Status:  needs_review
       Priority:  major              |    Milestone:  sage-6.8
      Component:  geometry           |   Resolution:
       Keywords:                     |    Merged in:
        Authors:  Michael Orlitzky   |    Reviewers:
Report Upstream:  N/A                |  Work issues:
         Branch:                     |       Commit:
  u/mjo/ticket/18454                 |  55da704f2f101cfdc25ba1c0b35f38072cb0e7f3
   Dependencies:                     |     Stopgaps:
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Comment (by novoselt):

 Well, it would be helpful to know in what sense the cone is "random". If
 it is a cone on a random set of rays, then dimension+1 is the only
 sensible upper bound to me - such a cone always can be constructed. In
 R^2^ it may be possible to force construction of cones with more than 4
 rays - given that the code can handle 4 instead of 3 for the whole space,
 probably it can live with 100. But if we are talking about the minimal
 number of extremal rays, then for R^1,2^ maximum is the dimension and for
 all others we can do anything - generate a random n-gon in a plane and
 lift it.

 In most cases I think you would want a strictly convex cone, so that's
 exactly what you want with bonus points if primitive generators are not
 necessarily in the same hyperplane. Algorithm: generate random vectors
 with positive last component. There may be an extra switch to allow linear
 subspaces in cones.

--
Ticket URL: <http://trac.sagemath.org/ticket/18454#comment:5>
Sage <http://www.sagemath.org>
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