Opened 7 years ago

Closed 7 years ago

#20125 closed enhancement (invalid)

better code for first_descent in coxeter groups

Reported by: Frédéric Chapoton Owned by:
Priority: major Milestone: sage-duplicate/invalid/wontfix
Component: combinatorics Keywords: coxeter
Cc: Travis Scrimshaw, Christian Stump, Darij Grinberg Merged in:
Authors: Frédéric Chapoton Reviewers:
Report Upstream: N/A Work issues:
Branch: public/20125 (Commits, GitHub, GitLab) Commit: 0c6eaafb86b446dac84e118a644ecf0c974036f8
Dependencies: Stopgaps:

Status badges

Description

I propose to treat the unit of the group in a special way. The test is cheap.

Change History (7)

comment:1 Changed 7 years ago by Frédéric Chapoton

Branch: public/20125
Cc: Travis Scrimshaw Christian Stump Darij Grinberg added
Commit: 98a56f40d0d88385cfed673f9b4db117d0b93100
Keywords: coxeter added
Status: newneeds_review

New commits:

98a56f4shortcuts for descents of the unit element in Coxeter groups

comment:2 Changed 7 years ago by git

Commit: 98a56f40d0d88385cfed673f9b4db117d0b931000c6eaafb86b446dac84e118a644ecf0c974036f8

Branch pushed to git repo; I updated commit sha1. New commits:

0c6eaaftrac #20125 another try using is_one

comment:3 Changed 7 years ago by Frédéric Chapoton

Status: needs_reviewneeds_work

This is not very convincing, it seems to be slower than before..

comment:4 Changed 7 years ago by Travis Scrimshaw

I think that because the identity element is rare, this won't really help speed up many computations because of the overhead of the extra data needed and function calls.

comment:5 Changed 7 years ago by Frédéric Chapoton

Milestone: sage-7.1sage-duplicate/invalid/wontfix
Status: needs_workpositive_review

ok, then let us close this as invalid.

Maybe the overloading of is_one is still a good idea that could be done in #19870 ?

comment:6 Changed 7 years ago by Travis Scrimshaw

Yes, that is a good idea.

comment:7 Changed 7 years ago by Volker Braun

Resolution: invalid
Status: positive_reviewclosed
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