Thanks Edzer and Hengl. It works. But R is really shaking when large grids are processed. We wish there is improvement of sp in the future like GIS handling grids. Regards Yong
________________________________ From: Edzer Pebesma [mailto:[EMAIL PROTECTED] Sent: Tue 20/05/2008 6:11 PM To: Yong Li Cc: r-sig-geo@stat.math.ethz.ch Subject: Re: [R-sig-Geo] How to subset a spatial grid? Have you tried Map1 <- Map[1:100,1:100] ? Note that this works differently for SpatialGridDataFrames and SpatialPixelsDataFrames; the first knows about [rows,cols,bands], the second about [pixels, bands]. -- Edzer Yong Li wrote: > Dear All, > > I want to subset a large spatial grid (2000*2000) into many smaller > grids for further processing in my simulation models. Could anyone do it > before and any tips will be highly appreciated? > > Library(rgdal) > Map <- readGDAL("yong.img") # one image from erdras imagine > Map$va <- Map$band1 > Map$band1 <- NULL > ???? > Map1 <- a subset of Map$va based on selected cols and rows. > ????...... > > Cheers > > Yong Li > > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@stat.math.ethz.ch > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > [[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
