Selected subset of all colour palettes
- This is the agreed set of colour palettes to be used for maps and figures
- They are all 1) Colour blind safe, 2) Computer screen safe and 3) printer safe
### Load the package or install if not present
if (!require("RColorBrewer")) {
install.packages("RColorBrewer")
library(RColorBrewer)
}
## Loading required package: RColorBrewer
par(mfrow = c(3,3))
for(col_i in c('YlGn','RdPu', 'PuRd', 'BrBG', 'RdBu', 'RdYlBu', 'Set3', 'Set1')){
display.brewer.pal(n = 5, name = col_i)
}
- A machine-readable approach to color specification is as hexadecimal triplets.
- Here is how the RColorBrewer RdYlBu palette is actually stored:
for(col_i in c('YlGn','RdPu', 'PuRd', 'BrBG', 'RdBu', 'RdYlBu', 'Set3', 'Set1')){
print(col_i)
print(brewer.pal(n = 5, name = col_i))
}
## [1] "YlGn"
## [1] "#FFFFCC" "#C2E699" "#78C679" "#31A354" "#006837"
## [1] "RdPu"
## [1] "#FEEBE2" "#FBB4B9" "#F768A1" "#C51B8A" "#7A0177"
## [1] "PuRd"
## [1] "#F1EEF6" "#D7B5D8" "#DF65B0" "#DD1C77" "#980043"
## [1] "BrBG"
## [1] "#A6611A" "#DFC27D" "#F5F5F5" "#80CDC1" "#018571"
## [1] "RdBu"
## [1] "#CA0020" "#F4A582" "#F7F7F7" "#92C5DE" "#0571B0"
## [1] "RdYlBu"
## [1] "#D7191C" "#FDAE61" "#FFFFBF" "#ABD9E9" "#2C7BB6"
## [1] "Set3"
## [1] "#8DD3C7" "#FFFFB3" "#BEBADA" "#FB8072" "#80B1D3"
## [1] "Set1"
## [1] "#E41A1C" "#377EB8" "#4DAF4A" "#984EA3" "#FF7F00"
# or for more levels
brewer.pal(n = 10, name = "RdYlBu")
## [1] "#A50026" "#D73027" "#F46D43" "#FDAE61" "#FEE090" "#E0F3F8" "#ABD9E9"
## [8] "#74ADD1" "#4575B4" "#313695"
The leading # is just there by convention. Parse the hexadecimal string like so: #rrggbb, where rr, gg, and bb refer to color intensity in the red, green, and blue channels, respectively. Each is specified as a two-digit base 16 number, which is the meaning of "hexadecimal" (or "hex" for short). Here's a table relating base 16 numbers to the beloved base 10 system.
All colour palettes
### Show all the colour schemes available
par(cex = .6)
display.brewer.all()
### Set the display a 2 by 2 grid
par(mfrow=c(2,2))
### Generate random data matrix
rand.data <- replicate(8,rnorm(100,100,sd=1.5))
### Draw a box plot, with each box coloured by the 'Set3' palette
boxplot(rand.data,col=brewer.pal(8,"Set3"))
### Draw plot of counts coloured by the 'Set3' pallatte
br.range <- seq(min(rand.data),max(rand.data),length.out=10)
results <- sapply(1:ncol(rand.data),function(x) hist(rand.data[,x],plot=F,br=br.range)$counts)
plot(x=br.range,ylim=range(results),type="n",ylab="Counts")
cols <- brewer.pal(8,"Set3")
lapply(1:ncol(results),function(x) lines(results[,x],col=cols[x],lwd=3))
### Draw a bar chart
table.data <- table(round(rand.data))
cols <- colorRampPalette(brewer.pal(8,"Dark2"))(length(table.data))
barplot(table.data,col=cols)
