[FIX] improve colorbar in mosaic display

[Remi-Gau]

• Closes [BUG] Colorbar is unreadable with plot_stat_map in mosaic mode #4283

Changes proposed in this pull request:

• increase width of colorbar in mosaic display

[github-actions]

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[Remi-Gau]

Too big I guess.
Also the font size needs to be adapted.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.06%. Comparing base (abb80ff) to head (8963dad).
Report is 9 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4284      +/-   ##
==========================================
+ Coverage   91.85%   92.06%   +0.20%     
==========================================
  Files         144      144              
  Lines       16419    16423       +4     
  Branches     3434     3436       +2     
==========================================
+ Hits        15082    15120      +38     
+ Misses        792      761      -31     
+ Partials      545      542       -3     

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macos-latest_3.10_test_plotting	91.85% <100.00%> (?)
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windows-latest_3.11_test_plotting	91.83% <100.00%> (?)
windows-latest_3.12_test_plotting	91.83% <100.00%> (?)
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[Remi-Gau]

To try a few different cuts

from nilearn import datasets, plotting

stat_img = datasets.load_sample_motor_activation_image()
for i in range(1, 15):
    display = plotting.plot_stat_map(stat_img, display_mode="mosaic", 
                                     annotate=True, 
                                     cut_coords=i, 
                                     output_file=f"test_{i}.png")

[Remi-Gau]

with different number of cuts

[tsalo]

It looks awesome, thank you! Any chance you could modify the labels as well?

[Remi-Gau]

will do
juggling with a bunch of bug fixes and also trying to deal with admonition in the bids spec and there is only 24 hours in one day... sigh...

[tsalo]

There's definitely no rush on my part. Tedana will bump its nilearn requirement only once 0.10.4 is released, which will probably be a couple of months from now.

[Remi-Gau]

probably sooner than this actually

we want to have a quick new release that will just be bug fixes

[tsalo]

Ah, in that case, maybe something like the following at line 566?

-        for tick in self._colorbar_ax.yaxis.get_ticklabels():
-            tick.set_color(tick_color)
-        self._colorbar_ax.yaxis.set_tick_params(width=0)
+        self._colorbar_ax.yaxis.set_tick_params(
+            width=0,
+            color=tick_color,
+            labelsize=self._colorbar_width * 100,
+        )

[bthirion]

Just wondering: isn't it ultimately simpler to reduce the figsize in order to have all labels not dwarfed by the plot size ?

[Remi-Gau]

Just wondering: isn't it ultimately simpler to reduce the figsize in order to have all labels not dwarfed by the plot size ?

thanks for the hint @bthirion, changing the default figure size seems easier.

will copy paste a few examples to let you judge

[Remi-Gau]

[Remi-Gau]

The default figure size is now much more in the range of that of the other displays.

[tsalo]

Wow, changing the figure size worked wonders!

[bthirion]

LGTM, thx.