#14085: Ambient spaces for dual and affine root systems
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       Reporter:  nthiery            |         Owner:  sage-combinat
           Type:  enhancement        |        Status:  new          
       Priority:  major              |     Milestone:  sage-5.7     
      Component:  combinatorics      |    Resolution:               
       Keywords:                     |   Work issues:               
Report Upstream:  N/A                |     Reviewers:  Dan Orr, ... 
        Authors:  Nicolas M. ThiƩry  |     Merged in:               
   Dependencies:                     |      Stopgaps:               
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Description changed by nthiery:

Old description:



New description:

 This ticket implements ambient spaces for dual and affine root
 systems. So now all finite and affine crystallographic root systems
 have an ambient space, except for relabeled ones (to be handled in a
 separate ticket).

 Upcoming applications:

 * Plotting #4237
 * Affine permutation representations built from the ambient space
 * Macdonald polynomials
 * Affine weight ring (in waiting for #7922 for weight rings built from
   the root or weight lattice)

 A couple things handled by this patch:
 - Fixing a couple whitespaces
 - Standard color scheme (to be used by #4237)
 - Fundamental weights computed from simple roots (finite type)
 - Better handling of the smallest base ring for the ambient space
   (toward ambient spaces over fields/rings like RR)
 - Better handling of dual types: in particular make sure the dual
   CartanType belongs to the appropriate CartanType classes; this
   allowed to remove now unnecessary code.
 - Fix the embedding of the root lattice into the extended weight
   lattice for type BC dual. A Type free approach would be better.

--

-- 
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/14085#comment:1>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica, 
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