Data Vis: Creating Colors in R Flashcards
how to use colors in R
Save the South Park palette to a vector
Once you find a color palette you like, you can save the colors as a vector and assigning the result to an object
Colors are data that you have to load and save into your workspace environment to use in your graphics
For example, if I want to use the “google” palette and use them in a barplot, I would do the following:
google.cols <- piratepal(palette = “google”,
trans = .2)
barplot(height = 1:5,
col = google.cols,
border = “white”,
main = “Barplot with the google palette”)
package
RColorBrewer
package great for getting (and even creating) color palettes
colorRamp2
Create color function from colorRamp2
part of the “circlize” package
allows you to easily generate shades of colors based on numerical data.
smoking.colors <- circlize::colorRamp2(breaks = c(0, 15, 25),
colors = c(“blue”, “green”, “red”),
transparency = .2)
color kuler
tool that allows you to determine the exact RGB values for a color on a screen. For example, let’s say that you wanted to use the exact colors used in the Google logo. To do this, you need to use an app that allows you to pick colors off your computer screen. On a Mac, you can use the program called “Digital Color Meter.” If you then move your mouse over the color you want, the software will tell you the exact RGB values of that color. In the image below, you can see me figuring out that the RGB value of the G in Google is R: 19, G: 72, B: 206. Using the rgb() function, I can convert these RGB values to colors in R. Using this method, I figured out the four colors of Google!
Store the colors of google as a vector:
google.col <- c(
rgb(19, 72, 206, maxColorValue = 255), # Google blue
rgb(206, 45, 35, maxColorValue = 255), # Google red
rgb(253, 172, 10, maxColorValue = 255), # Google yellow
rgb(18, 140, 70, maxColorValue = 255)) # Google green
Print the result
google.col
##[1] “#1348CE” “#CE2D23” “#FDAC0A” “#128C46”
