[BUG/ISSUE] Restricted range differences incorrectly all zero in some emissions column sum plots about gcpy HOT 1 CLOSED

I have pushed commit 01b912c to the master branch. We now ensure that if all values in a data array are zero, that the white color will be placed at the appropriate position in the color scale.

Matplotlib normalizes the data into a range of 0..1 for plotting. For difference color scales (i.e. the bottom 4 plots), if all values are zero, then the white color will get placed at color value 0.5, in the center of the range. For non-difference color scales (the top 2 plots), the white color will get placed at the start of the color scale (at 0.0).

Here are some example using GCHP 12.4.0 as both Ref and Dev (ensuring that all diffs will be zero):

O3 at surface:

O3 zonal mean:

from gcpy.