Area covered by a point cloud with R - r

I have a cloud of points scattered in a 2D Euclidean space. I would like to calculate the area inside the polygon linking the most extreme (=peripheral) points of the cloud. In other words, I would like to estimate the area covered by the cloud in this space.
Is there a formula in R?
Thanks a lot for any response
Julien


This is called the convex-hull problem; R built-in chull function should do the work. To count area, you may use a formula from here.
EDIT: Even better; splancs package has areapl function. So the function solving your problem should look like this:
cha<-function(x,y){
chull(x,y)->i
return(areapl(cbind(x[i],y[i])))
}
For instance:
library(splancs);
x<-rnorm(20);rnorm(20)->y;
#Some visualization
i<-chull(x,y);plot(x,y);polygon(x[i],y[i]);
#The area
cha(x,y);

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EDIT
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