Steve HarozXKCD's #painbow colormap and dataset are now on CRAN #rstats.
install.packages("painbow")
library(painbow)
ggplot(painbow_data) +
aes(x=x, y=y, fill=value) +
geom_raster(interpolate = TRUE) +
scale_fill_painbow()
More info: https://github.com/steveharoz/painbow
Also, #painbow has been ported to:
* javascript/D3 by @recifs https://observablehq.com/@fil/xkcd-painbow-color-map
* python/matplotlib https://github.com/NichtJens/matplotlib-xkcd-painbow-cmap