clipping polygons, overlaying big polygon on polygons
On Sun, 21 Feb 2010, Markus Loecher wrote:
Dear all, I apologize if this is too simple a question as it does appear to be a basic GIS operation but I have not found the appropriate function that performs a clipping of polygons into boundaries given by a (larger "outer") polygon. I tried overlay() from package sp and clipPolys from package PBSmapping but none converted the "inner" polygons into new ones laying inside the boundaries given by the outer polygon.
Maybe a basic GIS operation should be done in a GIS? Otherwise, please feel free to consult threads on the license problems of gpclib, and about the R-forge rgeos package. If you'd like to contribute such an intersection (I think you want the intersection between an arbitrary SpatialPolygons object and a simple SpatialPolygons object for the outer polygon) function tool to rgeos, or at least a sketch of how it might work, that would be helpful. Roger
Any help would be greatly appreciated, Thanks, Markus [[alternative HTML version deleted]]
_______________________________________________ R-sig-Geo mailing list R-sig-Geo at stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo
Roger Bivand Economic Geography Section, Department of Economics, Norwegian School of Economics and Business Administration, Helleveien 30, N-5045 Bergen, Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43 e-mail: Roger.Bivand at nhh.no