[R] How does the cex parameter scale circles?

Al Roark
Wed, 09 Mar 2011 15:04:36 -0000

I'm wondering how the cex parameter is used to scale circles (i.e. does it
scale the radius, diameter, area, circumference, etc.?). In my case I'm
using lattice with filled circles (pch=19).

Based on example, it looks like R scales the radius of the circle:

library(lattice)
dta<-data.frame(x=rep(1,6),y=rep(1,6),sz=c(1,2,4,8,16,32))
xyplot(x~y,data=dta,col=rgb(0,0,0,50,maxColorValue=255),cex=dta$sz,pch=19)

But I haven't been able to find confirmation in any R documentation, so any
assistance would be much appreciated. Cheers.
	[[alternative HTML version deleted]]