if(require(maptools, quiet = TRUE) & require(lattice, quiet = TRUE)) {
nc <- readShapePoly(system.file("shapes/sids.shp", package = "maptools")[1],
proj4string = CRS("+proj=longlat +datum=NAD27"))
xy <- coordinates(nc)
arrow <- list("SpatialPolygonsRescale", layout.north.arrow(),
offset = c(-76, 34.2), scale = 0.5)
xyplot(xy[, 2] ~ xy[, 1], aspect = "iso", panel = function(...){
adeg.panel.Spatial(SpObject = nc, sp.layout = list(arrow),
col = colorRampPalette(c("yellow", "blue"))(52), border =
"transparent")})
}Run the code above in your browser using DataLab