[GRASS-dev] r.watershed2 with MFD

[Markus Metz]

MFD is now ready for testing. So far, MFD with different settings of the
convergence factor works fine for elev_lid972_1m and elevation in the
North Carolina dataset.
Please read the updated documentation before using it!

A note on elev_lid972_1m: in order to get usable results, I changed
vertical units to millimeter with
r.mapcalc "elev_lid972_1m.1mm = round(elev_lid972_1m * 1000)"
Then try convergence = 1, 5, and 10, that gives a nice illustration of
the effect of the convergence factor.

<elevation>: most areas show SFD-like flow because the DEM doesn't
really offer more directions. But compare to r.terraflow output.

Changes in MFD output compared to SFD apart from flow accumulation
flow direction: not changed
basins, half-basins and streams: changed, looks usable for
elev_lid972_1m, but not for elevation
slope length (LS factor) and slope steepness (S factor): 99% identical,
differences not scatted but clumped, reason yet unknown, seems usable

I can not commit to grass7 (no write access or too stupid), therefore I
want to ask you developers if one of you could get the mfd module
including .svn entries developed against grass7 from here
http://markus.metz.giswork.googlepages.com/r.watershed.mfd.tar.gz
and commit the changes to grass7. The code has been indented with
grass_indent.sh
Single flow direction method is unaltered.
There is one global change in r.watershed, flow accumulation is now
DCELL, no longer CELL.

Thanks,

Markus