Median and quartile on violin plots in ggplot2

Question

I would like to draw some violin plots with ggplot2, but I noticed that median and first and third quartile are not automatically displayed. I believe these plots would be m

Answer 1

One way to do this is to just put a thin box plot over the top of it. Here's an example with the iris data:

require(ggplot2)
ggplot(iris,aes(Species,Sepal.Length))+geom_violin()+geom_boxplot(width=.1)