I am a new user of python and trying to read Summerell et al's FOTRAN code into python. This code is used to determining contributing area as viewed from a groundwater perspective. Rather than flow accumulation as we know it, it conceives accumulation to be permissible even when a cell is outside a catchment, for as long as it is at a higher elevation, it can potentially contribute flow to a lower cell.
For a cell ...
process_cell(target, current):
mask(current) = 1;
UPNESS(target) = UPNESS(target) + 1;
for i = each cell adjacent to current
if elev(i) equals nodata then
mask(i) = 1;
else if elev(i) greater than or equals elev(current) then
if mask(i) equals 0 then
call process_cell(target, i);
endif
endif
endfor
end;
where mask(current) is a temporary mask grid that tracks which cells have been processed for each target UPNESS cell (UPNESS(target)); UPNESS(target) is the output cell for the sum of all cells monotonically uphill; and elev(current) is the input grid cell corresponding to UPNESS(current).
For the whole DEM ...
for n = each cell in grid
if elevn not_equals nodata
for i = each cell in grid
maski = 0;
endfor
UPNESSn = 0;
process_cell(n,n);
endif
endfor;
end:
Thank you
