Graph plot default options before first call to plot() fail

[jm58660]

Documentation for graph_plot.py is something like

sage: G = graphs.WheelGraph(15)
sage: P = G.plot()

. . . some explanation, list of options . . .

sage: sage.graphs.graph_plot.DEFAULT_PLOT_OPTIONS['vertex_shape'] = 's'
 . . .

If the user runs second example, the result is

AttributeError                            Traceback (most recent call last)
<ipython-input-2-aa626427af43> in <module>()
----> 1 sage.graphs.graph_plot.DEFAULT_PLOT_OPTIONS['vertex_shape'] = 's'

AttributeError: 'module' object has no attribute 'graph_plot'

That's because .plot() runs import sage.graphs.graph_plot which is needed for DEFAULT_PLOT_OPTIONS to work. This patch adds import to second example.

CC: @nathanncohen

Component: documentation

Author: Jori Mäntysalo

Branch/Commit: 2ccbf2b

Reviewer: Nathann Cohen

Issue created by migration from https://trac.sagemath.org/ticket/19451

[nathanncohen]

comment:1

So the bug is that you have to import the module first? The reason why the second call works is that .plot() loads it for you.

Nathann

[nathanncohen]

comment:3

Hmmmmm.. I think that the DEFAULT_SHOW_OPTIONS dictionary actually gives its data to GraphPlot.show, and not to GenericGraph.show.

Nathann

[jm58660]

Branch: u/jmantysalo/graph_plot_default_options_before_first_call_to_plot___fail

[jm58660]

Commit: 2ccbf2b

[jm58660]

comment:5

I suggest adding an import-line before first example of using DEFAULT_SHOW_OPTIONS.

---

New commits:

2ccbf2b

Add an import-line to example.

[nathanncohen]

Author: Jori Mäntysalo

[nathanncohen]

Reviewer: Nathann Cohen

[vbraun]

Changed branch from u/jmantysalo/graph_plot_default_options_before_first_call_to_plot___fail to 2ccbf2b