MATLAB function for searching sources of catchment (edited)

Search sources of the catchment starting from its outlet by DFS. Those sources are ordered by 1) length, 2) single value at source, or 3) summation of values via channel from source to outlet. Usage examples - Select farthest source -- 2D distance source = riverSource([x y], stx, sty); or source = riverSource([x y], stx, sty, Mode="sum", Value=dl); -- 3D distance source = riverSource([x y], stx, sty, Value=el, CellSize=500); - Select highest source source = riverSource([x y], stx, sty, Mode="single", Value=el); - Select source of highest cumulative sediment flux quantity source = riverSource([x y], stx, sty, Mode="sum", Value=qso); - List up all sources order by channel length sources = riverSource([x y], stx, sty, N="all"); or sources = riverSource([x y], stx, sty, Mode="sum", Value=dl, N="all"); - List up top 5 sources order by source elevation sources = riverSource([x y], stx, sty, Mode="single", Value=el, N=5);