[DOC] Example of user-defined linestyle (TikZ linestyle)

[rougier]

This is an example showing user-defined linestyle copying name and style of TikZ.

[NelleV]

I'd remove those two lines, thought I honestly don't have a strong feeling about it.

[NelleV]

Thanks again for a very nice addition to the gallery.

[rougier]

This could be the base for new linestyles (MEP ?):

Name	Linestyle	Value
-	Solid	(0, ())
.:dense	Densely dotted	(0, (1, 1))
.:normal or .	Dotted	(0, (1, 5))
.:loose	Loosely dotted	(0, (1, 10))
--:dense	Densely dashed	(0, (5, 1))
--:normal or --	Dashed	(0, (5, 5))
--:loose	Loosely dashed	(0, (5, 10))
-.:dense	Densely dashdotted	(0, (3, 1, 1, 1))
-.:normal or -.	Dashdotted	(0, (3, 5, 1, 5))
-.:loose	Loosely dashdotted	(0, (3, 10, 1, 10))
-..:dense	Densely Dashdotdotted	(0, (3, 1, 1, 1, 1, 1))
-..:normal or -..	Dashdotdotted	(0, (3, 5, 1, 5, 1, 5))
-..:loose	Loosely Dashdotdotted	(0, (3, 10, 1, 10, 1, 10))

[afvincent]

I mention this just in case: there was some discussion related to line style patterns in #6547 a while ago, and the values that were chosen for the '-', ':' and '-.' line styles are a bit different.

Personally, I think it may be a good idea to add some extra default line styles like this PR suggest. Quite often, I wish there was (at least) a "dashdotdotted" style available.

About the example, I would have 2 remarks:

• it might be confusing to use the names "dotted", "dashdotted" and "dashed" for styles that do not use the default values.
• is it necessary to use plt.xticksand plt.yticks instead of the OO methods ax.set_xticks and ax.set_yticks?

Apart from these, I find the example to be very nice, as it may provide to the users some ready-to-use values for line style patterns, without having them to try a bunch of values on their own (like I often did...)

[rougier]

@afvincent Thanks for the review.

1. The names come from TikZ actually.
2. No reason to use plt.xticks, I need to change that.
3. Dotted /dashed: I didn't know what are the default values so I tried to guess them

Also thanks for the link to the PR. Do you now if there's a way to have round caps in 2.0 ?

[rougier]

Actually it doesn't work with ax.set_yaxis()

[tacaswell]

Line2D.set_dash_capstyle

http://matplotlib.org/api/lines_api.html#module-matplotlib.lines

There is also a dash_jointstyle

[rougier]

@tacaswell Thanks. I would (personally) prefer round caps by defaults but I imagine it has been already discussed.

[rougier]

Is there anything else to do with this PR ?

[tacaswell]

backported to v2.x as 7ed77e4