[GRASS-user] watershed creation between two points

[Michaël Rabotin]

Hi everybody, a question concerning watershed creation.
I've got an hydrological network and a map of points. I want to create
watershed. Currently I use the r.water.outlet command to do this. But Know I
want to create watershed only between two nodes of my network (it is not a
real watershed on the common hydrological point of view; it's just only a
part of this).
I've got a solution but I don't know if it's the good way: create each
watershed with one outlet point and after overlay each watershed with
another watershed to erase the part which overlay. But I need to know in
which way to overlay (need to find which outlet is upstream or downstream of
another outlet). I need to know  which  watershed is  upstream of an other
watershed
So I think I need to use a network (v.net command) but how to find that a
point is upstream or downstream of another point ?
Is it a way more simple to do it ? (using a command like r.water.outlet but
with limit in downstream and upstream to create a watershed only between two
points; and not between one point and the beginning of the hydrological
network)?
Thanks for your responses !!!


Mick
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