Colors and text in R

Colours

See Color Pitfalls on this webpage.

The colorspace package can be used to A LOT of things. Examples:

• Desaturating the color of some categories in a ggplot
• Testing for color vision deficiency
• Non-linear pallette scaling

Text

See package ggtext for ways to fx. color text labels, titles, etc. based on categories in data.

• Just specify the text using HTML code and specify the relevant argument in ggplot2::theme() using the function ggtext::element_markdown().
  • See an example of how to color your title in question 3 of lab5 at UoA.

See also gridtext for text rendering support for grid graphics in R.

Fonts

See Fonts in R for a small introduction

Getting new fonts

Download font online:

1. Go to font download site, fx. Google Gruppo
2. Click download
3. When downloaded, extract it 3a) On windows, click the Gruppo-regular file and press “Install”
4. In R, use the cairo graphics device 4a) In Rstudio: Tools -> Global options -> General -> Graphics (top) -> Backend -> Choose cairo 4b) In Rmarkdown: Include knitr::opts_chunk$set(dev.args = list(png = list(type ="cairo"))) in setup chunk.
5. Refer to the new font by it’s folder name in your system. Fx. ggplot2::element_text(family = "Gruppo")

References

• “Selecting colours in R”
  • Various R functions to generate colors
• The Colorspace R package
  • “A Toolbox for Manipulating and Assessing Colors and Palettes”
• “Coloring in R’s Blind Spot” by Achim Zeileis and Paul Murrell
  • A walkthrough of new R color and palette functions introduced with R version 4.0.0

Practical advice on how to use colors most “efficiently” in your plots

• Chapters 4 and 19 of “Fundamentals of Data Visualization” by Claus O. Wilke.