costrasterGen           Generate a cost Raster
errorGen                Generate interpolation error stats from
                        validation datasets
ipdw                    Inverse Path Distance Weighting
ipdwInterp              Inverse Distance Weighting with custom
                        distances
pathdistGen             Generate a stack of path distance raster
                        objects
rm_na_pointslayers      Remove NA points features and drop
                        corresponding raster stack layers
