> On Mar 12, 2016, at 11:27 AM, Marine Regis <marine.re...@hotmail.fr> wrote: > > Hello, > > > > I have two rasters with different resolution and projection.
Generally posting questions about spatial functions will get faster and better responses on the sig-geo mailing list: https://stat.ethz.ch/mailman/listinfo/R-SIG-Geo/ Otherwise it may take a few days for Roger Bivand to come around and do "clean up" by answering and then using his broom to whisk you over there. -- David. > > > >> r1 > > class : RasterLayer > > dimensions : 2510, 5233, 13134830 (nrow, ncol, ncell) > > resolution : 56, 56 (x, y) > > extent : 503198, 796246, 4917498, 5058058 (xmin, xmax, ymin, ymax) > > coord. ref. : +proj=utm +zone=18 +datum=WGS84 +units=m +no_defs +ellps=WGS84 > +towgs84=0,0,0 > > data source : in memory > > names : layer > > values : 1, 8 (min, max) > > > >> r2 > > class : RasterBrick > > dimensions : 3250, 6570, 21352500, 1 (nrow, ncol, ncell, nlayers) > > resolution : 30, 30 (x, y) > > extent : 265380.5, 462480.5, 4984457, 5081957 (xmin, xmax, ymin, ymax) > > coord. ref. : +proj=tmerc +lat_0=0 +lon_0=-73.5 +k=0.9999 +x_0=304800 +y_0=0 > +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs > > data source : H:\users\rast_temp.tif > > names : rast_temp > > > > My objective is to merge the two rasters into a single raster. As the two > rasters have different resolution and projection, I have used the function > projectRaster (package raster) like this: > > > r <- projectRaster(from=r1, to=r2, method="ngb", alignOnly=TRUE) > > > > However, I got this warning message: > > > > Warning message: > > In projectRaster(x, crs = projection(y)) : 'from' has no cell values > > > > and yet, the two rasters have values: > > > >> hasValues(r1) > > [1] TRUE > > > >> hasValues(r2) > > [1] TRUE > > > > When I remove the argument "alignOnly=TRUE", the code seems to work but I > don't want that r1 has the same projected extent than r2 (I want to keep the > original extent of r1). > > > > Why do I get this warning message ? > > > > Thank you very much for your help. > > Marine > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. David Winsemius Alameda, CA, USA ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
