An introduction to ggplot2

When should you use ggplot2?

You should use ggplot to make most of your figures, because it:

• is a coherent language for visualizing data (vs. the ‘plot’ function, which developed in an ad-hoc way)
• makes many tasks much easier, such as: visualizing a third (z) variable; saving your plot; automating plotting and formatting tasks
• creates beautiful plots and is very flexible

I use ggplot2 to generate almost all my figures, with the exception of some spatial figures and a few specialized plots. My experience has been that ggplot2 often chokes on larger raster or shape files. But, there are some great resources for visualizing spatial data using ggplot2 (e.g., ggmap and an example from Casey O’Hara).

Good resources

• My awesome cheatsheet which I thought was the greatest until….

• The official cheatsheet came out!!! They are both great…you should get both of them.

• I highly recommend Winston Chang’s book (which provides a great overview of ggplot2) and his website.