jgrass modules are capable to compute flowaccumulation from given
flowdirection grid [solved] (Tank you Andrea!)
another thing. when I use Terraflow with MFD, how are the flowdirections
expressed in the flowdirection grid? I get values between -1 and 255, but I'm
not really shure how to treat them/ what they express.
Can anybody help?
Thanks
Manuel
--
Dr. Manuel Seeger
Wiss. Assistent Scientific Assistant
Physische Geographie Dpt. of Physical Geography
FB VI - Geographie/Geowissenschaften Geography/Geosciences
Universität Trier University of Trier
D - 54286 Trier
Tel.: +49-651-201 4557
Fax: +49-651-201 3976
Web: http://www.uni-trier.de/uni/fb6/geographie/mitarbeiter/Seeger/
another thing. when I use Terraflow with MFD, how are the
flowdirections expressed in the flowdirection grid? I get values
between -1 and 255, but I'm not really shure how to treat them/ what
they express.
M.D.F.= multi-dimensional flow
MDF directions:
(based upon the rules in r.terraflow's findDominant() funtion in
direction.cc)
32 64 128
16 * 1
8 4 2
so a value of 255 is flow in all directions, a value of 3 is E and SE, a
value of 65 is E and N, etc. I'm not sure exactly what 0 and -1
represent, hopefully that becomes obvious.
The r.terraflow help page talks about MDF a bit, it should really have
this info too.
see my dominant_dir.m and calc_terraflow_dir.m Matlab scripts in the
wiki add-ons page (raster section) for some simple exploration.