Extract ridge sources using flow direction, subbasin, and elevation.
- 1. Identify original ridge sources (RdgOrgSrc), which are cells that have no flow-in cells
or have very few flow-in proportion for Dinf (TODO).
- 2. Read subbasin and identify the boundary grids as potential ridges (RdgPotSrc).
- 3. Sort each subbasin's boundary cells by elevation, filter by the a given percent, e.g. 70%.
- 4. Filter RdgOrgSrc by RdgPotSrc.
Be caution, the derived ridge sources may need manually modification when further use.
@author : Liangjun Zhu
@changelog:
- 16-08-07 - lj - initial implementation.
- 17-08-09 - lj - reorganize and incorporate with pygeoc.
