id,summary,reporter,owner,description,type,status,priority,milestone,component,resolution,keywords,cc,merged,author,reviewer,upstream,work_issues,branch,commit,dependencies,stopgaps
19821,"Increase speed for Coxeter groups, Weyl groups, and quantum Bruhat graph",tscrim,sage-combinat,"The primary goal of this ticket is to improve the creation speed for the quantum Bruhat graph. We do this in a number of ways:
- Better management of data associated to `lattice.nonparabolic_positive_roots`.
- Implement a (temporary) cache of the lengths of elements.
In addition, we also provide some general speedups to all matrix groups and Coxeter groups that came from looking into the above improvements. The net result is over 12x speedup of the creation of the quantum Bruhat graph:
{{{
sage: W = WeylGroup(['D',5], prefix='s')
sage: %time G = W.quantum_bruhat_graph()
CPU times: user 14 s, sys: 60.6 ms, total: 14 s
Wall time: 14 s
}}}
whereas previously this took over 3 minutes to compute. The downside is this has a larger memory footprint because of the temporary cache, but repeatedly computing the lengths of the elements was far too expensive.
This also includes a speedup of iterating over the entire Coxeter/Weyl group.",enhancement,closed,major,sage-7.2,combinatorics,fixed,quantum bruhat graph,sage-combinat aschilling mshimo nthiery darij chapoton stumpc5 jipilab,,Travis Scrimshaw,Frédéric Chapoton,N/A,,0ce02a6f0a713edfb93db05e8b0f26b793c7932a,0ce02a6f0a713edfb93db05e8b0f26b793c7932a,,