annotate boxplot in ggplot2

Question

I\'ve created a side-by-side boxplot using ggplot2.

p <- ggplot(mtcars, aes(x=factor(cyl), y=mpg))
p + geom_boxplot(aes(fill=factor(cyl)))

Answer 1

One way is to simply make the data.frame you need, and pass it to geom_text or geom_label:

library(dplyr)

cyl_fivenum <- mtcars %>% 
    group_by(cyl) %>% 
    summarise(five = list(fivenum(mpg))) %>% 
    tidyr::unnest()

ggplot(mtcars, aes(x=factor(cyl), y=mpg)) + 
    geom_boxplot(aes(fill=factor(cyl))) + 
    geom_text(data = cyl_fivenum, 
              aes(x = factor(cyl), y = five, label = five), 
              nudge_x = .5)