get rid of PermutationsNK

[videlec]

The class PermutationsNK in sage.combinat.permutation_nk was only used for its iterative property. The latter can be replaced from the permutations in the itertools Python module.

see also: #10534

CC: @sagetrac-sage-combinat @tscrim @nthiery @hivert

Component: combinatorics

Author: Vincent Delecroix

Branch/Commit: c86ef49

Reviewer: Travis Scrimshaw

Issue created by migration from https://trac.sagemath.org/ticket/16472

[videlec]

New commits:

4aaf79a

trac #16472: get rid of PermutationsNK

[videlec]

Branch: u/vdelecroix/16472

[videlec]

Commit: 4aaf79a

[tscrim]

Changed commit from 4aaf79a to 3c6d532

[tscrim]

comment:3

Hey Vincent, I've added a note about itertools.permutations. If you okay with this change, then positive review.

---

New commits:

3c6d532

Review tweaks.

[tscrim]

Changed branch from u/vdelecroix/16472 to public/remove_PermutationsNK-16472

[videlec]

comment:4

Hey Travis,

Replying to @tscrim:

Hey Vincent, I've added a note about itertools.permutations. If you okay with this change, then positive review.

Yes. Makes sense!

Thanks

[videlec]

Reviewer: Travis Scrimshaw

[vbraun]

comment:5

sage -t --long src/sage/structure/sage_object.pyx
**********************************************************************
File "src/sage/structure/sage_object.pyx", line 1346, in sage.structure.sage_object.unpickle_all
Failed example:
    sage.structure.sage_object.unpickle_all()  # (4s on sage.math, 2011)
Expected:
    doctest:... DeprecationWarning: This class is replaced by Matrix_modn_dense_float/Matrix_modn_dense_double.
    See http://trac.sagemath.org/4260 for details.
    Successfully unpickled ... objects.
    Failed to unpickle 0 objects.
Got:
     * unpickle failure: load('/home/release/.sage/temp/localhost.localdomain/27038/dir_lefRCW//pickle_jar/_class__sage_combinat_permutation_nk_PermutationsNK__.sobj')
    doctest:1: DeprecationWarning: OrderedAlphabet is deprecated; use Alphabet instead.
    See http://trac.sagemath.org/8920 for details.
    doctest:839: DeprecationWarning: This class is replaced by Matrix_modn_dense_float/Matrix_modn_dense_double.
    See http://trac.sagemath.org/4260 for details.
    Failed:
    _class__sage_combinat_permutation_nk_PermutationsNK__.sobj
    ----------------------------------------------------------------------
    ** This error is probably due to an old pickle failing to unpickle.
    ** See sage.structure.sage_object.register_unpickle_override for
    ** how to override the default unpickling methods for (old) pickles.
    ** NOTE: pickles should never be removed from the pickle_jar! 
    ----------------------------------------------------------------------
    Successfully unpickled 585 objects.
    Failed to unpickle 1 objects.
**********************************************************************

[sagetrac-git]

Changed commit from 3c6d532 to c58d158

[sagetrac-git]

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

c58d158

trac #16472: dirty hack to make unpickling works!

[videlec]

comment:8

Hi Travis,

At least it works! I basically reproduced what I did a long time ago in sage.combinat.alphabet.

Vincent

[tscrim]

comment:9

Here's a less hacky way (IMO) to handle the unpickling (it's something that was done for partitions). Pick whichever one you think is best and you can set this to positive review.

---

New commits:

dd8600d	Fixed unpickling of old class that probably noone has a pickle of.
645ca8d	Fix to the fix.

[tscrim]

Changed branch from public/remove_PermutationsNK-16472 to public/remove_PermutationsNK_pickling-16472

[tscrim]

Changed commit from c58d158 to 645ca8d

[sagetrac-git]

Changed commit from 645ca8d to c86ef49

[sagetrac-git]

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

c86ef49

Fix pickling test

[videlec]

comment:11

Hey Travis,

Your version is definitely better. Thanks. But I got

sage -t --long combinat/permutation.py
**********************************************************************
File "combinat/permutation.py", line 7458, in sage.combinat.permutation.PermutationsNK.__setstate__
Failed example:
...
SyntaxError: EOL while scanning string literal

It is because of a backslash that escaped a ". I put a commit for this and now everything is fine so I set to positive review.

Thanks for your help.

Vincent

[tscrim]

comment:12

That what I get for testing it in the command line :P. Thanks for catching that.

[vbraun]

Changed branch from public/remove_PermutationsNK_pickling-16472 to c86ef49