Creates a new, cropped version of an existing raster
handle_crp = CropRaster ( handle_src , CropWindow [, name] )
integer: handle on the raster to be cropped
vector of length 4: first row, first column, last row, last column
(optional) character string
integer: handle on the newly created, cropped raster
Creates a new, cropped version of an existing flow raster. Returns a handle on the new raster.