Alternative default color cycle for matplotlib

Quick start

To set the colors in a single script:

Copy the lines from rg_friendly.py into the top of your script.

To set the colors for all scripts running in a single directory:

Copy the lines from rg_friendly.mplstyle to the end of the file matplotlibrc in your script directory. (Settings in the ./matplotlibrc will override the system and per-user matplotlibrc files.)

To make the colors available as a "style"

Figure out where your matplotlib style files should go. On my system, it's ~/.config/matplotlib/stylelib/. Copy the file rg_friendly.mplstyle into that folder. Then in your scripts you can do:

import pylab as plt
plt.style.use('rg_friendly')

For more details on setting up styles, see https://matplotlib.org/users/customizing.html

To make the colors the default for all plots

Figure out where your matplotlibrc file is. On my system, it's ~/.config/matplotlib/matplotlibrc. Append the contents of rg_friendly.mplstyle to that matplotlibrc file. (Note that the matplotlibrc file might not exist yet.)

For more details on matplotlibrc, see https://matplotlib.org/users/customizing.html

Discussion

Here are some new colors for matplotlib. When matplotlib version 2 came out, the new default color cycle was very nice looking but caused trouble for some colorblind users, such as myself and this fellow:

matplotlib/matplotlib#9460

Without any extensive consultation or scientific approach, I have tweaked the default matplotlib palette slightly so that it is not so degenerate to my eyes.

The colors were created according to the following rules:

• I started from the default matplotlib 2 color cycle.
• I changed the color codes until the colors were clearly disambiguated.
• When I changed the colors I tried to move them towards shades that had a very clear identity; i.e. there should be only one shade that most people would call "red", and another that most could agree is "pink". I was probably less successful on this since it's not typically the strength of a color-blind person.
• I ran it by some colleagues for input! Many thanks to their encouragement and rapid adoption of my suggestions.