Functions for getting the colors of RColorBrewer (i.e.: brewer.pal) without the limitation of only 9/11 color values, based on colorRampPalette.
For sequential palettes this is not essential since we have viridis. But for diverging palettes this is quit essential.
The sequential palettes names are Blues BuGn BuPu GnBu Greens Greys Oranges OrRd PuBu PuBuGn PuRd Purples RdPu Reds YlGn YlGnBu YlOrBr YlOrRd
The diverging palettes are BrBG PiYG PRGn PuOr RdBu RdGy RdYlBu RdYlGn Spectral And also cool_warm. The cool_warm palette is based on Kenneth Moreland's proposal (see ref). It goes from blue (cool) to ref (warm), based on well thought-out design elements.
BrBG(n)
PiYG(n)
PRGn(n)
PuOr(n)
RdBu(n)
RdGy(n)
RdYlBu(n)
RdYlGn(n)
Spectral(n)
Blues(n)
BuGn(n)
BuPu(n)
GnBu(n)
Greens(n)
Greys(n)
Oranges(n)
OrRd(n)
PuBu(n)
PuBuGn(n)
PuRd(n)
Purples(n)
RdPu(n)
Reds(n)
YlGn(n)
YlGnBu(n)
YlOrBr(n)
YlOrRd(n)
cool_warm(n)the number of colors (>= 1) to be in the palette.
A character vector of color names.
* Moreland, Kenneth. "Diverging color maps for scientific visualization." Advances in Visual Computing (2009): 92-103. url: http://www.kennethmoreland.com/color-maps/ The code was provided here: http://stackoverflow.com/a/44073011/256662 Thanks to the user YAK, who relied on the code from the Rgnuplot package (which is duplicated here, in order to save the need to import the entire package)
if (FALSE) {
library(RColorBrewer)
display.brewer.all(n = 11, type = "div")
title(main = "Divergent color palette")
display.brewer.all(n = 9, type = c("seq"))
title(main = "Sequential color palette")
img <- function(obj, nam) {
image(1:length(obj), 1, as.matrix(1:length(obj)),
col = obj,
main = nam, ylab = "", xaxt = "n", yaxt = "n", bty = "n"
)
}
par(mfrow = c(10, 1))
img(rev(cool_warm(500)), "cool_warm, (Moreland 2009)")
img(RdBu(500), "RdBu")
img(BrBG(500), "BrBG")
img(PiYG(500), "PiYG")
img(PRGn(500), "PRGn")
img(PuOr(500), "PuOr")
img(RdGy(500), "RdGy")
img(RdYlBu(500), "RdYlBu")
img(RdYlGn(500), "RdYlGn")
img(Spectral(500), "Spectral")
library(heatmaply)
heatmaply(cor(mtcars), colors = PiYG, limits = c(-1, 1))
heatmaply(cor(mtcars), colors = RdBu, limits = c(-1, 1))
}