How to create a pie chart in R
Pie charts do not represent a lot of value from a statistician’s perspective, but they are a simple way to show proportions in an easy manner to the layman.
> summary = table(mtcars$cyl)
> summary
4 6 8
11 7 14
> pie(summary)

Unfortunately,
standard pie() function does not allow percentages to show up on the
pie chart. We would have to calculate it ourselves manually.
> labels = summary * 100 / sum(summary)
> labels
4 6 8
34.375 21.875 43.750
> labels = round(labels)
> labels
4 6 8
34 22 44
> pie(summary,labels)
