bug in Partitions

[jhpalmieri]

Looks like there is a bug in Partitions. Partitions(n, max_slope=-1) should give the partitions of n with distinct parts, right?

sage: Partitions(2, max_slope=-1).list()
[[2]]
sage: Partitions(4, max_slope=-1).list()
[[4], [3, 1]]

But if you add the "length" keyword, it doesn't work anymore, at least not completely:

sage: Partitions(2, max_slope=-1, length=2).list()  # doesn't work
[[1, 1]]
sage: Partitions(4, max_slope=-1, length=2).list()  # works
[[3, 1]]
sage: Partitions(4, max_slope=-1, length=3).list()  # doesn't work
[[2, 1, 1]]

Depends on #12925

CC: @sagetrac-brunellus

Component: combinatorics

Keywords: partitions, days38

Author: Travis Scrimshaw

Reviewer: Benjamin Jones

Merged: sage-5.3.beta2

Issue created by migration from https://trac.sagemath.org/ticket/6538

[tscrim]

comment:2

Fixed by making changes to IntergerListLex and not increasing algorithm's complexity. Fixed some other bugs in IntegerListLex and Partitions when bad input is given.

Note: most of the work on this patch was done during Sage Days 38.

[tscrim]

Changed keywords from partitions to partitions, days38

[tscrim]

Author: Travis Scrimshaw

[benjaminfjones]

comment:3

The code you've written looks good. I think you should also add a few doctests in EXAMPLES or TESTS where appropriate to demonstrate that the issue in this ticket it resolved.

[benjaminfjones]

Work Issues: add doctests

[benjaminfjones]

Reviewer: Benjamin Jones

[tscrim]

comment:4

Doctests have been added.

Thanks for reviewing.