> The maptools package has a function for computing the centroids of > polygons - install that and try help.search("centroid").
x <- read.shape(system.file("shapes/sids.shp", package="maptools") mycentroid <- get.Pcent(x) _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo