[R] Controling width of boxes in boxplots

[Marcin Kozak]

Hi,

I want to add boxplots to a scatterplot:

plot(x,y, xlim=c(80,120),ylim=c(80,120))
boxplot(y,add=TRUE,at=118)
boxplot(x,add=TRUE,at=118,horizontal=TRUE)

How can I control the width of the boxes (say, I'd like them to be of
width 3 in the variables' scales). I've tried the "width" parameter
but failed.

Thanks in advance,
Marcin