Thanks Etienne and Erin. Both good approaches that seem to work Regards Terry
________________________________ From: Etienne B. Racine [mailto:etienn...@gmail.com] Sent: Thursday, 6 December 2012 11:19 PM To: Hodgess, Erin Cc: Beutel, Terry S; r-sig-geo@r-project.org Subject: Re: [R-sig-Geo] assigning names to iteratively generated rasters Terry, Maybe a more orthodox way of doing this is to use replace your loop with a list (I have nothing against lists, it's just more convenient to manipulate a bunch of objects at once) : raster_list <- lapply(1:8, function(i) { r <- sort(sample(1:180, 2, replace = FALSE)) c <- sort(sample(1:360, 2, replace = FALSE)) out <- crop(x, extent(x, r1 = r[1], r2 = r[2], c1 = c[1], c = c[2])) }) names(raster_list) <- raster.names # view op <- par(mfrow = c(2, 4)) lapply(raster_list, function(x) plot(extent(x))) par(op) If you really want to manipulate objects, you could use attach(raster_list). Etienne 2012/12/6 Hodgess, Erin <hodge...@uhd.edu<mailto:hodge...@uhd.edu>> Hi Terry, Try this: assign(paste("d",i,sep=""),crop(x,extent(x,r1=r[1],r2=r[2],c1=c[1],c=c[2])) ________________________________________ From: r-sig-geo-boun...@r-project.org<mailto:r-sig-geo-boun...@r-project.org> [r-sig-geo-boun...@r-project.org<mailto:r-sig-geo-boun...@r-project.org>] on behalf of Beutel, Terry S [terry.beu...@daff.qld.gov.au<mailto:terry.beu...@daff.qld.gov.au>] Sent: Thursday, December 06, 2012 1:27 AM To: r-sig-geo@r-project.org<mailto:r-sig-geo@r-project.org> Subject: [R-sig-Geo] assigning names to iteratively generated rasters Hi everyone I want to know how to iteratively assign names to rasters as I generate them, taking those names from a vector of preset names. For example, say I have a list of the names I want my rasters to inherit. ie > raster.names<-paste("d",1:8,sep="") > raster.names [1] "d1" "d2" "d3" "d4" "d5" "d6" "d7" "d8" Now I take a raster. eg > library(raster) > x<-raster() > x class : RasterLayer dimensions : 180, 360, 64800 (nrow, ncol, ncell) resolution : 1, 1 (x, y) extent : -180, 180, -90, 90 (xmin, xmax, ymin, ymax) coord. ref. : +proj=longlat +datum=WGS84 I can iteratively crop random sections from the raster eg for(i in 1:8){ > r<-sort(sample(1:180,2,replace=F)) > c<-sort(sample(1:360,2,replace=F)) > out<-crop(x,extent(x,r1=r[1],r2=r[2],c1=c[1],c=c[2])) } My question is this. Instead of saving each random crop as "out" in each iteration (and thus overwriting the previous iteration of "out"), how do I save sequential iterations with those names listed in raster.names. So for example in the first loop "out" would be saved as an object called d1, in the second as an object called d2 etc. Just to be clear, the random cropping here is just to serve an example, my real interest is in how I permanently keep rasters I generate from an iterative process under names I choose for them. Thanks for any help. > Dr Terry Beutel Senior Scientist Agri-Science Queensland [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org<mailto:R-sig-Geo@r-project.org> https://stat.ethz.ch/mailman/listinfo/r-sig-geo _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org<mailto:R-sig-Geo@r-project.org> https://stat.ethz.ch/mailman/listinfo/r-sig-geo [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
