Dark-mode diverging colormaps

Three diverging colormaps have been added: "berlin", "managua", and "vanimo".

They are dark-mode diverging colormaps, with minimum lightness at the center,

and maximum at the extremes. These are taken from F. Crameri's Scientific

colour maps version 8.0.1 (DOI: https://doi.org/10.5281/zenodo.1243862).

.. plot::

:include-source: true

:alt: Example figures using "imshow" with dark-mode diverging colormaps on positive and negative data. First panel: "berlin" (blue to red with a black center); second panel: "managua" (orange to cyan with a dark purple center); third panel: "vanimo" (pink to green with a black center).

import numpy as np

import matplotlib.pyplot as plt

vals = np.linspace(-5, 5, 100)

x, y = np.meshgrid(vals, vals)

img = np.sin(x*y)

_, ax = plt.subplots(1, 3)

ax[0].imshow(img, cmap=plt.cm.berlin)

ax[1].imshow(img, cmap=plt.cm.managua)

ax[2].imshow(img, cmap=plt.cm.vanimo)

'RdYlBu', 'RdYlGn', 'Spectral', 'coolwarm', 'bwr', 'seismic',

'berlin', 'managua', 'vanimo']),

'RdYlGn', 'Spectral', 'coolwarm', 'bwr', 'seismic',

'berlin', 'managua', 'vanimo'])