Robert, At some point you made this comment:
>>> (as you are dealing with large >>> files, I think it is more efficient to first make a stack and then >>> write the results to a brick) But I have some doubts: bN = brick(N1,N2,N3,...,N72) where N1 = raster(paste(midir,"NDV_19990101__Extract.img",sep="")) etc takes a very long time. Is a file on disk being written somewhere? Is overlay() going to be any faster with brick than with stack objects? ie: bNv2 <- overlay(bN, bSM, fun=fun1,filename="bNv2.tif",overwrite=TRUE,NAflag=0) faster than sNv2 <- overlay(sN, sSM, fun=fun1,filename="sNv2.tif",overwrite=TRUE,NAflag=0) ? (bN, bSM, brick objects; sN, sSM, stack objects) When you write a brick to a file, can you control if the resulting file is going to be BSQ or BIL? Are the files written by writeRaster() identical for stack and brick objects? writeRaster(bNv2, filename="bNv2b.tif",overwrite=TRUE,format="GTiff",datatype='INT2U',NAflag=0) writeRaster(sNv2, filename="sNv2b.tif",overwrite=TRUE,format="GTiff",datatype='INT2U',NAflag=0) Thanks Agus _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo
