R For Dummies, 2nd Edition

Chapter 18

Looking At ggplot2 Graphics

In This Chapter

Installing and loading the ggplot2 package

Understanding how to use build a plot using layers

Creating charts with suitable geoms and stats

Adding facets to your plot

One of the strengths of R is that it’s more than just a programming language — it also has thousands of packages written and contributed by independent developers. One of these packages, ggplot2, is tremendously popular and offers a new way of creating insightful graphics using R.

Much of the ggplot2 philosophy is based on the so-called “grammar of graphics,” a theoretically sound way of describing all the components that go into a graphical plot. You don’t need to know anything about the grammar of graphics to use ggplot2 effectively, but now you know where its name comes from.

In this chapter, you first install and load the ggplot2 package and then take a first look at layers, the building blocks of the ggplot2 graphics. Next, you define the data, geoms, and stats ...