On Sat, 7 Apr 2012, Margherita Di Leo wrote:

r.basin produces several maps for every run, which are flow direction,
accumulation, Horton ordered streams etc.. Prefix parameter is simply a
string given by the user in order to distinguish all the maps produced by a
single run of the program, i.e. every set of coords for outlet. For
example,

madi,

  I thought this is the case, but wanted to know rather than assume.

Threshold parameter is the same of r.watershed. 'Autothreshold ' flag'
simply uses a threshold area of 1 km^2 and is intended as a tentative.

  Again, rather than assuming I wanted to be sure I understood.

For what concerns r.stream.basin, it is a typo in the documentation,
correct is r.stream.basins, thanks for pointing me out, I just updated it
in the description file.
r.wf.py and r.ipso.py are in the addOns repository:

  Ah, I see why they did not download for me: I added the .py extention to
the g.estension command. Now I know to leave it off.

Please note that r.basin is intended to work with only one outlet at time.
This means you should script it in a for cycle if you run it for several
outlets.

  I understand this.

 You can't give to r.basin the coordinates directly from a vector map.

  But, can I use the coordinates of a rasterized stream network?

I have indicated to run r.stream.extract before r.basin because most of the
times the calculated stream network doesn't match with the natural one, so
that your coordinates should be adjusted to match the calculated stream
network in order to get a result from r.basin. By the way, in a first run
you can give a try with your coordinates.

  The outputs of r.stream.extract on two different project sub-watersheds
are, as far as I can see on the display, only about 5-10% of the vector
stream network, and all at the lower ends of the basins in which they
appear. I can send screen shots if you'd like to see the differences.

  After downloading and building the 'missing' three modules I'll try
v.to.rast on the natural stream network (at 1:24,000 scale, just like the
elevation data) and see what r.basin tells me.

Many thanks,

Rich

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