legends don't save correctly

[sagetrac-mhampton]

The new plot legends look great, but generate an error when you try to save them.

For example:

a1 = plot(sin,-pi,pi,legend_label='sin')
a2 = plot(cos,-pi,pi,legend_label='cos',rgbcolor='red')
two_plots = a1+a2
two_plots.save('./two_plots.png')

gives the error:

KeyError: 'pop(): dictionary is empty'

Apply: attachment: trac_10244_legend_label_fix_v3.patch and attachment: trac_10244-reviewer.patch

CC: @kcrisman @jasongrout @novoselt

Component: graphics

Author: Marshall Hampton

Reviewer: Karl-Dieter Crisman

Merged: sage-4.6.2.alpha2

Issue created by migration from https://trac.sagemath.org/ticket/10244

[kcrisman]

comment:1

Thanks for noticing this, Marshall. In particular:

/Users/.../sage-4.6.1.alpha0/local/lib/python2.6/site-packages/sage/plot/plot.pyc in matplotlib(self, filename, xmin, xmax, ymin, ymax, figsize, figure, sub, axes, axes_labels, fontsize, frame, verify, aspect_ratio, gridlines, gridlinesstyle, vgridlinesstyle, hgridlinesstyle, show_legend, legend_options, axes_pad, ticks_integer, tick_formatter, ticks)
   1965             lopts.update(legend_options)
   1966             lopts.update(self.__legend_opts)
-> 1967             prop = FontProperties(family=lopts.pop('font_family'), weight=lopts.pop('font_weight'), \
   1968                     size=lopts.pop('font_size'), style=lopts.pop('font_style'), variant=lopts.pop('font_variant'))
   1969             color = lopts.pop('back_color')

So we've already popped everything while saving in .matplotlib, but then try to pop some other options like font_family. I would think those were already given in some @options thingie, but maybe they weren't. I don't have time to check more into this, but I suspect the suboptions decorator has something to do with this - maybe we never initialized them but then try to access them.

[jasongrout]

comment:2

Then a probably related issue is that this saving command:

plot(x,(x,0,1),aspect_ratio=1).save('test.png')

does not save a plot with aspect_ratio=1. If this isn't related, I guess we should open a new ticket.

[jasongrout]

comment:3

I wonder if something like #7981 (or a rebased and updated version) could fix this? I think the problem in my comment is directly related to #7981.

[kcrisman]

comment:4

Replying to @jasongrout:

I wonder if something like #7981 (or a rebased and updated version) could fix this? I think the problem in my comment is directly related to #7981.

Hmm, this seems quite likely - if the options are mostly used in show, not save. I'd have to actually try it out and follow the code through, though, and that won't happen soon :(

[sagetrac-mhampton]

comment:5

Unfortunately the current fix at #7981 does NOT fix this. Its extremely annoying for me, since I am currently in a project in which my group needs rather baroque plots and the legend is essential.

[sagetrac-mhampton]

comment:6

This seems like a clue:

sage: p= plot(x,(x,0,10),legend_label='Fantastic legend label', gridlines='major')
sage: print p._extra_kwds
{'gridlines': 'major'}

I would think that the legend info would show up in _extra_kwds, but I my understanding of the plotting code is weak.

[sagetrac-mhampton]

comment:8

I think I figured this out, patch coming in a moment.

[sagetrac-mhampton]

Fixes problem by adding suboptions decorator to save command

[sagetrac-mhampton]

Author: Marshall Hampton

[sagetrac-mhampton]

comment:9

Attachment: trac_10244_legend_label_fix.patch.gz