docs: def main():
      """Read GeoTiff raster data and perform log transformation.
      """
      input_tif = "../tests/data/Jamaica_dem.tif"
      output_tif = "../tests/data/tmp_results/log_dem.tif"
      rst = RasterUtilClass.read_raster(input_tif)
      # raster data (with noDataValue as numpy.nan) as numpy array
      rst_valid = rst.validValues
      output_data = np.log(rst_valid)
      # write output raster
      RasterUtilClass.write_gtiff_file(output_tif, rst.nRows, rst.nCols, output_data, rst.geotrans,
                                       rst.srs, rst.noDataValue, rst.dataType)