R: Data Analysis and Visualization

Using margin labels instead of legends for multiple-line graphs

While legends are the most commonly used method of providing a key to read multiple-variable graphs, they are often not the easiest to read. Labeling lines directly is one way of getting around this problem.

Getting ready

We will use the base graphics library for this recipe, so all you need to do is run the recipe at the R prompt. It is good practice to save your code as a script for use again later.

How to do it...

Let's use the gdp.txt example dataset to look at the trends in annual GDP of five countries:

gdp<-read.table("gdp_long.txt",header=T) library(RColorBrewer) pal<-brewer.pal(5,"Set1") par(mar=par()$mar+c(0,0,0,2),bty="l") plot(Canada~Year,data=gdp,type="l",lwd=2,lty=1,ylim=c(30,60), ...