r.watershd & topo index
bahram at gis.uiuc.edu
Thu Apr 1 16:29:12 EST 1993
Here is what the man page says about negative values in accumulation file:
Negative numbers indicate that those cells possibly have
surface runoff from outside of the current geographic region.
Thus, any cells with negative values cannot have their
surface runoff and sedimentation yields calculated accurately.
The overflow message MAY be due to large number of cells. Try -m option.
It is very slow however.
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