SpatialPixelsDataFrame cannot be reprojected without converting to points, and a lot of manual handling / resampling. The raster package can do it though, see ?projectRaster
e.g. library(sp) data(meuse.grid) m = SpatialPixelsDataFrame(points = meuse.grid[c("x", "y")], data = meuse.grid) proj4string(m) <- CRS("+init=epsg:28992") library(raster) library(rgdal) r <- raster(m) newproj <- "+proj=longlat +ellps=WGS84" pr <- projectExtent(r, newproj) # project the values of RasterLayer 'r' to the new RasterLayer pr <- projectRaster(r, pr) sessionInfo() R version 2.12.0 (2010-10-15) Platform: x86_64-pc-mingw32/x64 (64-bit) locale: [1] LC_COLLATE=English_Australia.1252 LC_CTYPE=English_Australia.1252 [3] LC_MONETARY=English_Australia.1252 LC_NUMERIC=C [5] LC_TIME=English_Australia.1252 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] rgdal_0.6-28 raster_1.5-16 sp_0.9-72 loaded via a namespace (and not attached): [1] grid_2.12.0 lattice_0.19-13 tools_2.12.0 On Wed, Oct 20, 2010 at 1:37 PM, Julian Burgos <jmbur...@uw.edu> wrote: > Dear list, > I have a problem trying to change the projection of a > SpatialPixelsDataFrame, from UTM to lat/long. My object has the following > characteristics: > > > summary(mb) > Object of class SpatialPixelsDataFrame > Coordinates: > min max > X -14.17196 -13.76879 > Y 63.75071 63.96791 > Is projected: TRUE > proj4string : [+proj=utm +zone=28 +datum=WGS84] > Number of points: 5669540 > Grid attributes: > cellcentre.offset cellsize cells.dim > X -14.17189 1.347473e-04 2992 > Y 63.75074 5.944386e-05 3654 > Data attributes: > Min. 1st Qu. Median Mean 3rd Qu. Max. > 108.5 230.3 256.9 283.0 287.9 987.6 > > when using the spTransform I get the following error message: > > > mb=spTransform(mb,CRS("proj=longlat +datum=WGS84")) > Error in spTransform(mb, CRS("proj=longlat +datum=WGS84")) : > error in evaluating the argument 'CRSobj' in selecting a method for > function 'spTransform' > > Any ideas what is the problem? > Many thanks, > > Julian Burgos > > Julian Mariano Burgos > Hafrannsóknastofnunin/Marine Research Institute > Skúlagata 4, 121 ReykjavÃk, Iceland > SÃmi/Telephone : +354-5752037 > BréfsÃmi/Telefax: +354-5752001 > Netfang/Email: jul...@hafro.is, jmbur...@uw.edu > > [[alternative HTML version deleted]] > > > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@stat.math.ethz.ch > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > > -- Michael Sumner Institute for Marine and Antarctic Studies, University of Tasmania Hobart, Australia e-mail: mdsum...@gmail.com [[alternative HTML version deleted]]
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