[R] calculate area between intersecting polygons

[Hans W Borchers]

Remko Duursma <remkoduursma <at> gmail.com> writes:
> 
> Here is a different solution:
> 
> library(gpclib)
> p1 <- as(poly1, "gpc.poly")
> p2 <- as(poly2, "gpc.poly")
> 
> area.poly(p2) + area.poly(p1) - area.poly(union(p1,p2))
> 
> I.e., take areas of both polygons and subtract the union (check
> plot(union(p1,p2)) ) to get the area of the intersection.
> 
> greetings,
> Remko

Thanks for the hint. I didn't know that the "polygon clipping library" has
been packaged for R, I could have used it several time before. There are
too many package, though this time I admit it would have been easy to hit
upon it by searching CRAN carefully.

Hans Werner

Hans Werner