pyflwdir.FlwdirRaster.subbasins_area#

FlwdirRaster.subbasins_area(area_min: float, uparea: ndarray | None = None) → tuple[ndarray, ndarray][source]#

Return subbasins with a minimum contributing area of area_min.

Moving upstream from basin outlets, a new subbasin starts at tributaries whose contributing area exceeds area_min. A new interbasin starts when its area exceeds the same threshold.

Parameters:

  • area_min (float) – Minimum subbasin area [km2].

  • uparea (2D array of float, optional) – Raster of upstream area [km2]. Calculated on the fly if omitted.

Returns:

  • subbas (2D array of int32) – Raster of unique subbasin IDs.

  • idxs_out (1D array of int) – Linear indices of subbasin outlet cells.