#26500 closed enhancement (fixed)
Add is_derangements method to Permutation
Reported by:  tscrim  Owned by:  

Priority:  minor  Milestone:  sage8.5 
Component:  combinatorics  Keywords:  
Cc:  Merged in:  
Authors:  Travis Scrimshaw  Reviewers:  Anne Schilling 
Report Upstream:  N/A  Work issues:  
Branch:  c2fe978 (Commits, GitHub, GitLab)  Commit:  
Dependencies:  Stopgaps: 
Description
It is useful to check if a permutation is a derangement for, e.g., the Tsetlin library steady state distribution.
Change History (17)
comment:1 Changed 4 years ago by
 Branch set to public/combinat/add_derangement_check26500
 Commit set to 1da1753e0a58b7b41079fe0095f9f784646533e3
comment:2 Changed 4 years ago by
 Status changed from new to needs_review
comment:3 Changed 4 years ago by
 Reviewers set to UC Davis Math 165 class
 Status changed from needs_review to positive_review
comment:4 Changed 4 years ago by
really ??
 the argument should be self and not p
 it could use
not self.fixed_points()
comment:5 Changed 4 years ago by
 Status changed from positive_review to needs_work
Sorry, we were using this as an example of the workflow for a class. I will make these changes shortly.
comment:6 Changed 4 years ago by
 Commit changed from 1da1753e0a58b7b41079fe0095f9f784646533e3 to a27c526802c26b3541fd6af0a0b869f1876d4e8f
Branch pushed to git repo; I updated commit sha1. New commits:
a27c526  Some tweaks to is_derangement.

comment:8 Changed 4 years ago by
 Reviewers changed from UC Davis Math 165 class to UC Davis Math 165 class, Anne Schilling
 Status changed from needs_review to positive_review
comment:9 Changed 4 years ago by
 Status changed from positive_review to needs_work
not fixed, there remains a p..
comment:10 Changed 4 years ago by
 Commit changed from a27c526802c26b3541fd6af0a0b869f1876d4e8f to c2fe978b169cbaa3ef54ca27cd8e9b01d8307264
Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:
c2fe978  Some tweaks to is_derangement.

comment:11 Changed 4 years ago by
 Status changed from needs_work to positive_review
Now it is definitely fixed. Sorry about that.
comment:12 Changed 4 years ago by
 Branch changed from public/combinat/add_derangement_check26500 to c2fe978b169cbaa3ef54ca27cd8e9b01d8307264
 Resolution set to fixed
 Status changed from positive_review to closed
comment:13 Changed 4 years ago by
 Milestone changed from sage8.4 to sage8.5
This should be retargeted for 8.5.
comment:14 followup: ↓ 15 Changed 4 years ago by
 Commit c2fe978b169cbaa3ef54ca27cd8e9b01d8307264 deleted
 Reviewers changed from UC Davis Math 165 class, Anne Schilling to Anne Schilling
Who is "UC Davis Math 165 class"?
comment:15 in reply to: ↑ 14 Changed 4 years ago by
Replying to jdemeyer:
Who is "UC Davis Math 165 class"?
Well, we did this together with a whole class of about 30 students I was teaching last quarter.
comment:16 Changed 4 years ago by
As far as I know, there is no precedent for using something like that as reviewer, so I'm a bit hesitant to put that in the release notes.
comment:17 Changed 4 years ago by
I dunno, I think it would be a nice feature in the release notes :)
New commits:
Add is_derangement to Permutation.