[R] custom point shapes

[baptiste Auguié]

Hi,

I'm new to R, but a search through the list didn't quite solve this  
problem: I want to draw a few ellipses (or any custom shape for that  
matter) at given locations in a graph. I know how to plot points from  
my data, set the point type "pch" to any built in value, but I do not  
know how to specify a custom shape.
A search for drawing ellipses gave me functions to plot one at a  
given location, possibly using some dataset but only to display a  
confidence interval or other convex hull. Nothing to use as pch.

Say I have this data:

x<-c(1:10)
y<-x^2

I would like to plot (x,y) with some ellipses of custom aspect ratio  
for every point.

Thanks,

Best regards,

baptiste