To annotate the text inside a plot created by ggplot2, we can use annotate function. It is used to give some explanation about the plot or add any useful information that will help readers to understand the plot in a better way. Sometimes, we might want to change the angle of the annotated text, especially in cases where we have some information that is presented vertically in the plot, therefore, we can use angle argument of the annotate function.
Consider the below data frame −
> x<-runif(10,2,5) > y<-runif(10,5,6) > df<-data.frame(x,y) > df
x y 1 4.086537 5.890591 2 2.271184 5.697052 3 3.335322 5.827102 4 2.155897 5.984699 5 4.054110 5.620492 6 3.936053 5.766108 7 4.341102 5.345369 8 2.450337 5.960743 9 4.992243 5.520061 10 2.776401 5.443892
Loading ggplot2 package and creating a plot with annotated text −
> library(ggplot2) > ggplot(df,aes(x,y))+geom_point()+annotate("text",x=3,y=5.4,label="ScatterPlot")
Changing the angle of text “ScatterPlot” −
> ggplot(df,aes(x,y))+geom_point()+annotate("text",x=3,y=5.4,label="ScatterPlot",angle=9 0)