Opened 3 years ago
Closed 3 years ago
#25467 closed enhancement (fixed)
Implement discriminant up and downstairs for reflection groups
Reported by:  stumpc5  Owned by:  

Priority:  major  Milestone:  sage8.3 
Component:  combinatorics  Keywords:  reflection group, discriminant, days93.51 
Cc:  tscrim, jmichel  Merged in:  
Authors:  Christian Stump  Reviewers:  Travis Scrimshaw 
Report Upstream:  N/A  Work issues:  
Branch:  3f2667e (Commits, GitHub, GitLab)  Commit:  3f2667eb4e274a987692e1f081b8e4189fdb7897 
Dependencies:  Stopgaps: 
Description (last modified by )
The descriminant is the the product alpha_H^{e_H} where alpha_H are the linear forms of the hyperplanes and e_H are their stabilizer order.
Change History (12)
comment:1 Changed 3 years ago by
 Branch set to u/stumpc5/add_liner_forms_for_reflecting_hyperplanes_in_reflection_group
comment:2 Changed 3 years ago by
 Cc tscrim jmichel added
 Commit set to 3d4f036304188cf81b51293d4d9a99e0325576b8
 Component changed from PLEASE CHANGE to combinatorics
 Description modified (diff)
 Keywords reflection group discriminant days93.51 added
 Summary changed from Add liner forms for reflecting hyperplanes in reflection group to Implement discriminant up and downstairs for reflection groups
 Type changed from PLEASE CHANGE to enhancement
comment:3 Changed 3 years ago by
 Commit changed from 3d4f036304188cf81b51293d4d9a99e0325576b8 to 294e728d661b91cb7ab76ad58e69df516e1614f5
Branch pushed to git repo; I updated commit sha1. New commits:
294e728  added doctests for power

comment:4 Changed 3 years ago by
 Commit changed from 294e728d661b91cb7ab76ad58e69df516e1614f5 to 3e2059d00dce95991b07dae0652b5b3b0a223ee0
Branch pushed to git repo; I updated commit sha1. New commits:
3e2059d  added doctests for hyperplane linear functionals

comment:5 Changed 3 years ago by
 Status changed from new to needs_review
comment:6 Changed 3 years ago by
 Description modified (diff)
comment:7 Changed 3 years ago by
 Branch changed from u/stumpc5/add_liner_forms_for_reflecting_hyperplanes_in_reflection_group to public/combinat/discriminant_reflection_groups25467
 Commit changed from 3e2059d00dce95991b07dae0652b5b3b0a223ee0 to 25f078c7d59d99deb02d813561c6f35722bd639b
 Reviewers set to Travis Scrimshaw
I made a few changes, but I kept the solve function, which is now part of the code, in that method because it currently used a few things from the method and I don't know of a good place to put it. At least, I would want to put it in the multivariate code, but then we would need to implement a univariate. Plus, we would need a reasonable method name. So because of this, I figured it would be best to postpone that for a later date.
New commits:
25f078c  Some reviewer changes.

comment:8 Changed 3 years ago by
 Status changed from needs_review to positive_review
okay, setting to positive review.
comment:9 Changed 3 years ago by
For the discriminant downstairs, we might use the following algorithm:
compute which monomials might appear as we already do and then interpolate by evaluating at random points.
comment:10 Changed 3 years ago by
 Commit changed from 25f078c7d59d99deb02d813561c6f35722bd639b to 3f2667eb4e274a987692e1f081b8e4189fdb7897
 Status changed from positive_review to needs_review
Branch pushed to git repo; I updated commit sha1 and set ticket back to needs_review. New commits:
3f2667e  Trivial fixing of docstring.

comment:11 Changed 3 years ago by
 Status changed from needs_review to positive_review
Trivial docstring fix.
comment:12 Changed 3 years ago by
 Branch changed from public/combinat/discriminant_reflection_groups25467 to 3f2667eb4e274a987692e1f081b8e4189fdb7897
 Resolution set to fixed
 Status changed from positive_review to closed
New commits:
started the discriminant of a reflection group
implemented the discriminant up and downstairs