On Sat, 26 Jan 2008, Marco Helbich wrote: > Dear List, > > I've calculated a kernel density estimation (splancs function) and now I > want to export the result as a kml-file to open it in the google earth > viewer, but I get stuck at converting the SpatialGridDataFrame to a > SpatialPixelDataFrame... > > here (http://www.zshare.net/download/689742375ef5fb/) you can download some > testdata and my R-code so far: > > ########### > data.shp <- readOGR("C:/", layer="events") > prj <- data.shp@ proj4string@ projargs > dat <- data.shp > str(dat) > poly.shp <- readOGR("C:/", layer="hull") > str(poly.shp) > > dat.SP <- as(dat, "SpatialPoints") > str(dat.SP) > pp_poi <- as.points([EMAIL PROTECTED],1], [EMAIL PROTECTED],2]) > poly <- > getPolygonCoordsSlot(getPolygonsPolygonsSlot(getSpPpolygonsSlot(poly.shp)[[1]])[[1]]) > polymap(poly) > points(pp_poi) > > grd <- GridTopology(cellcentre.offset=c(590511, 396191), cellsize=c(2000, > 2000), > cells.dim=c(30,25))
Here cellsize= is in metres, cells.dim= the numbers of columns and rows. > kbw2000 <- spkernel2d(pp_poi, poly, h0=2000, grd) > spplot(SpatialGridDataFrame(grd, data=data.frame(kbw2000)), > col.regions=terrain.colors(16)) > > test <- SpatialGridDataFrame(grd, data=data.frame(kbw2000)) > proj4string(test) <- CRS(prj) > str(test) > test1 <- spTransform(test, CRS("+proj=longlat +datum=WGS84")) > > ## here I got following error message: > # validityMethod(as(object, superClass)): Geographical CRS given to > non-conformant data > test2 <- spsample(test1, type="regular", cellsize=c(2000,2000)) But test1 is now in geographical coordinates, so 2K degrees is a bit extreme, and the validation mechanism traps you. I'm not sure what your cellsize and cell.dims should be here in longlat. > > # export the SpatialPixelDataFrame (Code (not testet) from the help-file) > tf <- tempfile() > SGxx <- GE_SpatialGrid(test2) > png(file=paste(tf, ".png", sep=""), width=SGxx$width, height=SGxx$height, > bg="transparent") > par(mar=c(0,0,0,0), xaxs="i", yaxs="i") > plot(x, xlim=SGxx$xlim, ylim=SGxx$ylim, setParUsrBB=TRUE) There is no x defined here. Roger > dev.off() > kmlOverlay(SGxx, paste(tf, ".kml", sep=""), paste(tf, ".png", sep="")) > ########### > > I appreciate every hint! Thanks. > Marco > > -- 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: [EMAIL PROTECTED] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo