Section 23 Single Categorical Variable: Pie Chart

23.1 Pie chart

• Pie chart is used for the categorical variables.

23.2 package base

data(mtcars)

x <- table(mtcars$cyl)

pie(x=x, labels=names(x), 
    col = c('red','blue','green'),
    main = 'Barplot of number of cylinders')

23.3 package ggplot2

g <- ggplot(data=mtcars, aes(x=factor(1), fill=factor(cyl)))
g <- g + geom_bar(width=1)
g <- g + coord_polar(theta='y')
g <- g + scale_fill_manual(values=c('red','lightblue','green'))
g + theme_bw()