Opened 4 years ago
Closed 4 years ago
#25067 closed enhancement (fixed)
Implement quantum group qnumbers
Reported by:  tscrim  Owned by:  

Priority:  major  Milestone:  sage8.2 
Component:  algebra  Keywords:  quantum groups, qanalogs 
Cc:  sagecombinat, darij, aschilling, bsalisbury01, andrew.mathas  Merged in:  
Authors:  Travis Scrimshaw  Reviewers:  Darij Grinberg 
Report Upstream:  N/A  Work issues:  
Branch:  e0893e0 (Commits, GitHub, GitLab)  Commit:  e0893e046355d1fd32a3d49fcce0a163d32ab354 
Dependencies:  Stopgaps: 
Description
Split off of #15508 for better granularity and to use it to build other tickets. Implements [n]_q
, [n]_q!
and q
binomials that appear in quantum groups.
Change History (7)
comment:1 Changed 4 years ago by
 Branch set to public/quantum_groups/q_numbers25067
 Commit set to 67c6ba01bb525a68ed88a5bfc4623d23f9a249ab
 Status changed from new to needs_review
comment:2 Changed 4 years ago by
 Commit changed from 67c6ba01bb525a68ed88a5bfc4623d23f9a249ab to e908d5996b85d0897794bd15b97456f5afcc6722
Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:
e908d59  Adding qanalogs used in quantum groups.

comment:3 Changed 4 years ago by
 Commit changed from e908d5996b85d0897794bd15b97456f5afcc6722 to e0893e046355d1fd32a3d49fcce0a163d32ab354
Branch pushed to git repo; I updated commit sha1. New commits:
e0893e0  documentation improvements

comment:4 Changed 4 years ago by
 Reviewers set to Darij Grinberg
 Status changed from needs_review to positive_review
Discussed with Darij and says good modulo his changes, which LGTM. So positive review. Thank you!
comment:5 Changed 4 years ago by
Sorry to be late to the party but are you aware of combinat/q_analogues.py
? In particular, this module provides functions q_int
, q_factorial
and q_binomial
(among others). I have not been through this ticket in detail but comparing the q_int
function in this ticket appears to be less general than the existing function because, in q_analogues.py
, q_int(n)
allows n
to be positive or negative whereas the q_int
function in this ticket requires n
to be nonnegative. On the other hand, the quantum integer that the existing q_int
returns is different to the one in this ticket.
I am not sure how much this ticket overlaps with the code that is already in sage but some one should check. At a minimum, I think that there should be some documentation links between this code and the preexisting code and, arguably, the code should be merged so that we don't have code providing similar functionality in different places. Different function names, or a more general syntax that allows one to choose between the different quantum integers, should also be considered.
Annoyingly, the q_int
defined in q_analogues.py
is the natural quantum integer to use in Hecke algebras whereas the q_int
defined in this ticket is what is required in the quantum group setting...so both are needed.
As I have not read through all of the code I won't set this back to needs work but my feeling is that it does need more work.
comment:6 Changed 4 years ago by
Oh, I see that there are already documentation links, so feel free to ignore the above. This said, adding a link from the documentation in combinat/q_analogues.py
to the code in this ticket would also be useful.
comment:7 Changed 4 years ago by
 Branch changed from public/quantum_groups/q_numbers25067 to e0893e046355d1fd32a3d49fcce0a163d32ab354
 Resolution set to fixed
 Status changed from positive_review to closed
New commits:
Adding qanalogs used in quantum groups.