DOC - SpanSelector widget documentation

[LindyBalboa]

Initial focus was to add a reference to AxesWidget.active in the documentation. I went ahead and made it numpy standard while I was in there.

Removed: I made the ignore method into _ignore so that it would not be build into the docs, as a user will have zero reason to call it.

Resolves #7009

[NelleV]

I am pretty sure this line is too long for the pep8 requirements (to be confirmed when travis finish running).

[NelleV]

PEP8: there are spaces missing after the comas.

[NelleV]

I am slightly confused on why the pep8 test pass here, while they don't for all of my students :(
Two lines are two long for our pep8 requirements:

widgets.py|1710 col 80| E501 line too long (96 > 79 characters)
widgets.py|1732 col 80| E501 line too long (89 > 79 characters)

Apart from this, and my additional comment, the patch looks good!

Thanks,
N

[QuLogic]

The changed file is listed in the known bad files list, so any PEP8 issues in it get ignored.

If your students wish to correct these issues, that would be much appreciated.

[QuLogic]

I'm not sure you should be changing the name here. Surely there are other callers that should be updated as well?

[LindyBalboa]

You are totally right. I thought I changed where it is called as well. I will take another look.

[LindyBalboa]

I can't seem to do a linebreak with doctest line 1732 and make it work. And I feel making that line shorter would just muddle it and look poor. It turns out there is in fact an example for SpanSelector in the examples folder, but since it is interactive, telling it to plot to the docs doesn't make much sense.

Should I just make a link to the example, and if so, how would I make that link?

[NelleV]

I think the following is fine::

>>> span = mwidgets.SpanSelector(ax, onselect, 'horizontal', 
                                 rectprops=rectprops)

[LindyBalboa]

So, Travis is giving this:

ValueError: Some exclude patterns were unnecessary as the files they pointed to either passed the PEP8 tests or do not point to a file:
E                 */matplotlib/widgets.py

Does that mean it can be removed from the list or am I missing something?

[Kojoley]

It seems you have fixed all pep8 problems in widgets.py, so yes, you should remove it from the pep8 exclusion list (this line in test_coding_standards.py).

[NelleV]

The failure on travis is unrelated. LGTM 👍

[jenshnielsen]

Failure is unrelated. Restarted the particular travis job to be sure

[tacaswell]

backported to v2.x as a2e56ad