Output Raster to GeoTiff format file.

        Args:
            f_name: output gtiff file name.
            n_rows: Row count.
            n_cols: Col count.
            data: 2D array data.
            geotransform: geographic transformation.
            srs: coordinate system.
            nodata_value: nodata value.
            gdal_type (:obj:`pygeoc.raster.GDALDataType`): output raster data type,
                                                                  GDT_Float32 as default.

def write_gtiff_file(f_name, n_rows, n_cols, data, geotransform, srs, nodata_value,
                         gdal_type=GDT_Float32):
        """Output Raster to GeoTiff format file.

        Args:
            f_name: output gtiff file name.
            n_rows: Row count.
            n_cols: Col count.
            data: 2D array data.
            geotransform: geographic transformation.
            srs: coordinate system.
            nodata_value: nodata value.
            gdal_type (:obj:`pygeoc.raster.GDALDataType`): output raster data type,
                                                                  GDT_Float32 as default.
        """
        UtilClass.mkdir(os.path.dirname(FileClass.get_file_fullpath(f_name)))
        driver = gdal_GetDriverByName(str('GTiff'))
        try:
            ds = driver.Create(f_name, n_cols, n_rows, 1, gdal_type)
        except Exception:
            print('Cannot create output file %s' % f_name)
            return
        ds.SetGeoTransform(geotransform)
        try:
            ds.SetProjection(srs.ExportToWkt())
        except AttributeError or Exception:
            ds.SetProjection(srs)
        ds.GetRasterBand(1).SetNoDataValue(nodata_value)
        # if data contains numpy.nan, then replaced by nodata_value
        if isinstance(data, numpy.ndarray) and data.dtype in [numpy.dtype('int'),
                                                              numpy.dtype('float')]:
            data = numpy.where(numpy.isnan(data), nodata_value, data)
        ds.GetRasterBand(1).WriteArray(data)
        ds = None