On Wed, 13 Jun 2007, Thomas Szegvary wrote: > Hello, I'm new to R and try to use the geostatistical packages. > I have a problem making grid from ESRI shapefiles. I imported the shapefile > (polygon) and projected the coordinates. Then I used spsample() to produce a > spatial points for the given regions resp. polygons. With points2grid I > wanted to produce the grid, which should be used for krige(), but a always > have an error message (see below). > > Script: >> #prepare grid >> europe <- readShapePoly("R course/country/europePoly.shp") >> proj4string(europe) = CRS("+init=epsg:4326") europe.tr <- > spTransform(europe,CRS("+init=epsg:3035")) >> europe.points <- spsample(europe.tr,type="regular",cellsize=100000) >> points2grid(europe.points) > x1 x2 > cellcentre.offset 2735004 1478310 > cellsize 100000 100000 > cells.dim 37 48 > Warning message: > grid has empty column/rows in dimension 2 in: points2grid(europe.points) >
This is a warning, not an error, and only means that at least one column/row in one dimension (so row most likely) has no points after removing the points not inside the polygons. Try: plot(europe.tr) points(europe.points, cex=0.5) to see where that might be. Hope this helps, Roger > > Thanks a lot > Thomas > > > > __ > > Thomas Szegvary > Institute of Environmental Geosciences > Department of Geosciences > University of Basel > Bernoullistrasse 30 > CH - 4056 Basel > > Tel. 41-61-267 04 82 > Fax. 41-61-267 04 79 > Email: [EMAIL PROTECTED] > www.radon.unibas.ch > www.unibas.ch/environment > > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@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: [EMAIL PROTECTED] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo