randomcoloR

An R package for generating attractive and distinctive colors.

The randomColor() function is ported from randomColor.js.

Let's quickly get some pretty random colors.

library(igraph)
library(randomcoloR)

k <- 200
plot(erdos.renyi.game(k, 0.1), vertex.label=NA,
     edge.lty="blank", vertex.color=randomColor(k))

We can specify a particular hue, such as red.

plot(erdos.renyi.game(k, 0.1), vertex.label=NA,
     edge.lty="blank", vertex.color=randomColor(k, hue="red"))

We can also get random colors with specific luminosity.

plot(erdos.renyi.game(k, 0.1), vertex.label=NA,
     edge.lty="blank", vertex.color=randomColor(k, luminosity="light"))

We can also ask for a set of optimally distinct colors so that colors in our plot are not too similar. If we use ggplot2 to select the color space for our states in the map below, we get many similar colors.

library(dplyr)
library(ggplot2)
library(maps)

states_map <- map_data("state")

ggplot(states_map, aes(x=long, y=lat, group=group, fill=region)) +
  geom_polygon(color="black") +
  guides(fill=FALSE)

Which states are green?

Instead, let's find the most distinctive set of colors for all states.

ggplot(states_map, aes(x=long, y=lat, group=group, fill=region)) +
  geom_polygon(color="black") +
  scale_fill_manual(values=distinctColorPalette(length(unique(states_map$region)))) +
  guides(fill=FALSE)

Now, which states are green?

When using ggplot2, we can specify a custom color palette.

ggplot(mtcars, aes(x=disp, y=mpg, col=as.factor(gear))) +
  geom_point(size=5) +
  scale_colour_manual(values=randomColor(length(unique(mtcars$gear)), luminosity="light")) +
  theme_bw()

You can use the default color space.

set.seed(8675309)

scales::show_col(distinctColorPalette(12), labels=FALSE)

Or an alternate color space.

scales::show_col(distinctColorPalette(12, altCol=TRUE), labels=FALSE)

And you can preprocess the color space with t-SNE for improved color separation in some circumstances

scales::show_col(distinctColorPalette(12, altCol=TRUE, runTsne=TRUE), labels=FALSE)

Installation from Github

To install this package from Github via the R console, type:

devtools::install_git("https://github.com/ronammar/randomcoloR")

It's also on CRAN:

install.packages("randomcoloR")