I've just added to the geoR tutorial page an script with examples on converting geoR's krige.conv() outputs to SpatialGridDataFrame and SpatialPixelDataFrame formats defined by the sp package
The relevant link is: http://leg.ufpr.br/geoR/tutorials/kc2sp.R These should be encapsulated on function in a (hopefully) near future to facilitate conversion of outputs from both, krige.conv() and krige.bayes() As usual, comments/suggestions/improvements etc are very welcome! Best P.J. Paulo Justiniano Ribeiro Jr LEG (Laboratorio de Estatistica e Geoinformacao) Universidade Federal do Parana Caixa Postal 19.081 CEP 81.531-990 Curitiba, PR - Brasil Tel: (+55) 41 3361 3573 Fax: (+55) 41 3361 3141 e-mail: paulojus AT ufpr br http://www.leg.ufpr.br/~paulojus On Sun, 14 Dec 2008, Roger Bivand wrote: > On Sun, 14 Dec 2008, Nicolas Meurisse wrote: > > > Hello, > > > > After kriging with the use of the krige.conv function, I would like to > > export my result under the grid format. In order to view it into a GIS. > > > > It was suggested to me to use the writeGDAL function into the rgdal package. > > However It looks like I have a problem of supported formats > > (dataset object of SpatialGridDataFrame-class or > > SpatialPixelsDataFrame-class > > ) that is not the same as the one resulting from my krige.conv function > > (kriging -class apparently) > > > > I tried several function to achieve this conversion (getRasterData, > > SpatialGridDataFrame, SpatialPixelsDataFrame, create2GDAL, points2grid...). > > But without any success. > > > > #my actual kriging script: > > pred.grid = expand.grid(seq(170000, 130000, l = 50), seq(190000, 160000, l = > > 50)) > > library(sp) > pred.grid$var3 <- 1 > coordinates(pred.grid) <- c("Var1", "Var2") > gridded(pred.grid) <- TRUE > > # Create a SpatialPixelsDataFrame or SpatialGridDataFrame object first > # - forced here by including a non-coordnate column to the data frame > > > myPred = krige.conv(myGData, loc = pred.grid, krige = krige.control(obj.m = > > myOLSMod)) > > myPred = krige.conv(myGData, loc = coordinates(pred.grid), > krige = krige.control(obj.m = myOLSMod)) > > # Krige with the coordinates of the object > > pred.grid$predict <- myPred$predict > > # add the predictions (and standard errors if you like) to the > # object, they are in the correct order; > # then write out, choosing the output column as desired > > tf <- tempfile() > writeGDAL(pred.grid["predict"], tf, drivername="GTiff") # not type="Byte"! > GDALinfo(tf) > > # I suppose you are using the temporary file here to test your approach > # as you ought to put the output file in a permanent place if you will > # need it later > > Hope this helps, > > Roger > > > image(myPred, loc = pred.grid, col = gray(seq(1, 0.1, l = 30))) > > > > #my conversion attempts > > tf <- tempfile() > > writeGDAL(myPred, tf, drivername="GTiff", type="Byte", options=NULL) > > [Erreur dans function (classes, fdef, mtable) : unable to find an inherited > > method for function "gridded", for signature "kriging"] > > > > Thanks a lot, > > > > Nicolas > > > > _______________________________________________ > > R-sig-Geo mailing list > > [email protected] > > 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 > [email protected] > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > _______________________________________________ R-sig-Geo mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
