#14261: Iwahori-Hecke algebra with several bases
-------------------------------------+-------------------------------------
Reporter: brant | Owner: sage-combinat
Type: enhancement | Status: needs_review
Priority: major | Milestone: sage-5.12
Component: combinatorics | Resolution:
Keywords: Iwahori Hecke | Merged in:
algebra | Reviewers: Andrew Mathas, Brant
Authors: Brant Jones, | Jones, Travis Scrimshaw
Travis Scrimshaw | Work issues:
Report Upstream: N/A | Commit:
Branch: | Stopgaps:
Dependencies: #13735 #14014 |
#14678 #14516 |
-------------------------------------+-------------------------------------
Comment (by tscrim):
For the `CoxeterGroup` vs `WeylGroup`, you must have chevie installed so
`CoxeterGroup` defaults to a permutation group implementation. Because of
this, I can't test it, but it should be in the `CoxeterGroups` category
and there should be a coercion between the different implementations of
the same group.
Actually on that note, instead of passing a Cartan type to the Iwahori-
Hecke algebra constructor, perhaps we should pass a Coxeter group instead.
A side note, this doesn't work for affine groups because the comparison of
elements in the Coxeter groups does not always agree with the Bruhat
order:
{{{
sage: G = CoxeterGroup(['A',2])
sage: s1,s2 = G.gens()
sage: G.one() < s1
False
sage: G.one() < s2
False
sage: G = CoxeterGroup(['A',2,1])
sage: s0,s1,s2 = G.gens()
sage: G.one() < s0
False
sage: G.one() < s1
True
sage: G.one() < s2
True
}}}
I've attached small patch which (crudely/proof of concept) fixes this by
using the Bruhat ordering for you to fold into your review patch.
--
Ticket URL: <http://trac.sagemath.org/ticket/14261#comment:51>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/groups/opt_out.
