lass='va'>var</span> <span class='op'>&lt;-</span> <span class='fu'>raster</span><span class='fu'>::</span><span class='fu'><a href='https://rdrr.io/pkg/raster/man/stack.html'>stack</a></span><span class='op'>(</span><span class='fu'><a href='https://rdrr.io/r/base/system.file.html'>system.file</a></span><span class='op'>(</span><span class='st'>"extdata"</span>, <span class='st'>"variables.tif"</span>,
                                 package <span class='op'>=</span> <span class='st'>"rangemap"</span><spa