Multiplication by identity in tableau.py and tableau_tuple.py

[darijgr]

This is similar to #14883 in that it removes a multiplication of a permutation by the identity permutation. This time the multiplication was not useless (it was meant to coerce the permutation into a symmetric group of large enough size), but that is easier done by just concatenating lists (given that the result is only needed as a list). There is a minor speedup (577µs to 496µs on the one of the doctested examples), but the purpose of this patch is really to replace a hack by a more logical manipulation.

Travis, feel free to fold this into your patch if you wish.

Depends on #14101

CC: @tscrim @sagetrac-sage-combinat

Component: combinatorics

Keywords: combinat, tableau, tableau tuple

Author: Darij Grinberg

Reviewer: Travis Scrimshaw

Merged: sage-5.12.beta5

Issue created by migration from https://trac.sagemath.org/ticket/14884

[darijgr]

Changed dependencies from 14101 to #14101

[tscrim]

comment:4

Hey Darij,

I believe taking the copy slice w[:] of w is unnecessary.

sage: L = [1, 2, 3]      
sage: k = L + [3, 5, 6]
sage: L
[1, 2, 3]

Could you remove this and repost?

Thanks,

Travis

[tscrim]

Reviewer: Travis Scrimshaw

[darijgr]

corrected version

[darijgr]

comment:5

Attachment: trac_14884-tableau_times_id-dg.patch.gz

Good point; fixed. Thanks for checking this.

[tscrim]

comment:6

Looks good to me. Thanks Darij.

[jdemeyer]

Merged: sage-5.12.beta5