fill option is broken for polar_plot

[sagetrac-whuss]

The fill option for polar_plot does not work correctly anymore.

The following two doctests don't produce the supposed output:

• Fill the area between two functions:

sage: polar_plot(cos(4*x) + 1.5, 0, 2*pi, fill=0.5 * cos(4*x) + 2.5, fillcolor='orange').show(aspect_ratio=1)

• Fill the area between several spirals:

sage: polar_plot([(1.2+k*0.2)*log(x) for k in range(6)], 1, 3 * pi, fill = {0: [1], 2: [3], 4: [5]})

This regression has been introduced with the changeset 12287 (Ticket: #5930).

Sage really needs a test framework for plots. Otherwise more and more regressions will creep in, without anybody noticing.

Component: graphics

Keywords: polar_plot, fill

Author: Wilfried Huss

Reviewer: Jason Grout

Merged: Sage 4.1.2.alpha2

Issue created by migration from https://trac.sagemath.org/ticket/6875

[sagetrac-whuss]

Attachment: trac_6875_fill_regression.patch.gz

[jasongrout]

comment:1

It still doesn't seem like the first example above works for me---I get a single solid figure. Is it supposed to have a band around it's edge?

[sagetrac-whuss]

Attachment: polar_1.png

The correct output of the first example

[sagetrac-whuss]

Attachment: polar_2.png

The correct output of the second example

[sagetrac-whuss]

comment:2

Replying to @jasongrout:

It still doesn't seem like the first example above works for me---I get a single solid figure. Is it supposed to have a band around it's edge?

I've attached two images with the correct output of the two examples.
Is this what you get with the patch?

[jasongrout]

comment:3

I compiled a fresh version of 4.1.1.alpha1 overnight, and everything seems to work on that. So positive review!

(Note to everyone else: the functions above were already in the doctests, but just were not working).

I wish this would have been working last week when I taught finding areas in polar coordinates! I'm glad you found the fix.

[sagetrac-mvngu]

Changed author from whuss to Wilfried Huss

[sagetrac-mvngu]

comment:4

Merged trac_6875_fill_regression.patch.

[sagetrac-mvngu]

Merged: Sage 4.1.2.alpha2

[sagetrac-mvngu]

Reviewer: Jason Grout