[GRASS-user] Algorithm in flow direction

[margherita]

Hi all

i have some question about the commands r.watershed and r.terraflow. By 
using both commands i obtained from a DEM a flow accumulation with the 
algorithm of the single flow direction and a flow accumulation with the 
algorithm of the multi flow direction. In both cases i did not enter the 
treshold of cell (i.e. in the flow accumulation if a grid cell value 
exceeds a certain threshold, it's part of the river, if not, it isn't)

Please can you let me know if there are default values of this threshold 
and, if yes, what they are, and if that value can be changed by the user 
and how.

Thanks a lot.

Regards

-- 
Ing. Margherita Di Leo
PhD Student 
Methods and Technologies for Environmental Monitoring
Department of Environmental Engineering and Physics (DIFA)

University of Basilicata 
Campus Macchia Romana
85100 - Potenza 
Italy

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