[GRASS-dev] r.sim.water strange behaviour

[Hanlie Pretorius]

Hi,

I recently posted about problems with r.sim.water and was advised to
compile GRASS from source with debugging symbols. I have now managed
to do so, using GRASS64SVN on Ubuntu 10.04 with the following options:
-----
CFLAGS="-g -Wall" LDFLAGS="-s" ./configure --with-png=internal
--with-libtiff=internal --with-geotiff=internal --with-jpeg=internal
--with-gif=internal --with-ecw=yes --with-expat=yes
--with-expat-inc=/usr/include/ --with-expat-lib=/usr/lib
--with-sqlite3=yes --with-geos=yes --with-python --with-libz=internal
--with-netcdf --with-sqlite --with-threads=yes --without-grass
--without-ogdi --with-pg=/usr/bin/pg_config --with-xerces=yes
--with-proj-share=/usr/share/proj --with-jpeg=yes --with-png=yes
--with-tcltk-includes=/usr/include/tcl8.4 --enable-largefile
--enable-64bit
-----

r.sim.water doesn't crash catastrophically any more now, but I still
get strange behaviour. The command I'm using is typically:

-----
r.sim.water elevin="lieb_dem_25m at PERMANENT" dxin="lieb_dem_25m_dx at PE\
RMANENT" dyin="lieb_dem_25m_dy at PERMANENT" rain_val=50 infil_val=0.0 \
     manin_val=0.1 depth="lieb_depth_100m_res at PERMANENT" niter=10
outiter\
=2 diffc=0.8 hmax=0.3 halpha=4.0 hbeta=0.5
-----

The strange behaviour is:

* region at 100m resolution, 822120 cells, water depth output range
0.004148 to 0.086017

* region at 50m resolution, 3288480 cells (no depth map produced):
-----
GRASS 6.4.0svn (sa_tm_29deg_E_extract):/usr/local/src/grass64_release
> r.sim.water elevin=lieb_dem_25m at PERMANENT
dxin=lieb_dem_25m_dx at PERMANENT dyin=lieb_dem_25m_dy at PERMANENT
depth=lieb_depth_50m_res at PERMANENT --overwrite
default nwalk=6576960, rwalk=6576960.000000

Min elevation = 1498.64 m
Max elevation = 2437.77 m
Mean Source Rate (rainf. excess or sediment) = 0.000006 m/s or kg/m2s
Mean flow velocity = 1.166484 m/s
Mean Mannings = 0.170641
Number of iterations = 13 cells
Time step = 10.72 s
ERROR: nwalk (7000001) > maxw (7000000)!
-----

* region at 25m, 13153920 cells, water depth output range 0.00 to 0.00

This doesn't make much sense to me. Any ideas?

I'm not sure where to get the extra debugging information if it's not
being sent to the terminal.

Perhaps it's something to do with my dataset, but I have no idea what
it could be. My dataset is available on
http://www.nedbib.za.net/rsimwater/sa_tm_29deg_E_extract.zip.


Thanks
Hanlie