I'm new to GIS - more so in GRASS GIS. I installed GRASS GIS 6.4.3svn in my Windows 7 machine. No problem in installation.
- Downloaded SRTM-Geotiff file
- Location, Mapset all o.k
- Used r.in.gdal to import SRTM file
- Filled the sinks using r.terraflow
- Masked the filled raster
- Zoomed the required region & set the computational region
- Ran r.watershed using threshold=10000
- Got drainge, basin, stream & visual rasters
- Visual rendering of rasters (drainge, basin, stream & visual) - o.k
- Different Watersheds (basins) displayed for entire area
- Zoomed stream raster to find lat/lon of mouth of river (cross checked with Google earth)
- Converted the lat/lon as decimal
- Ran r.water.outlet using stream as input & gave the lat/lon as easting & northing
- Sadly the output display is blank
- Rerun r.water.outlet - only a small dot in the lat/lon point. No delineation of watershed for the given easting & northing
- All the above procedures as per manuals
- Self learning of GRASS GIS - no formal training
Since I'm new here, I'm not permitted to upload the result images - Sorry...
What is the mistake I'm doing? How to get the watershed (basin) for the given lat/lon? Kindly help. Thanks in advance...