[GRASS-user] Overlapping vector areas

[David Townshend]

Hi

I am trying the generate watersheds for several outlets by looping
over r.water.outlet in a python script (attached). The basin procedure
is that for each outlet point (read using v.info -t), my script runs
r.water.outlet, r.to.vect and v.patch, to combine the watersheds into
a simgle vector map. I am connecting the watersheds to the outlet
points by setting the category value in the output from r.to.vect,
i.e. before patching. The trouble is that some of the watersheds
overlap, e.g. where an outlet lies inside another watershed. v.patch
doesn't seem to handle this too well, and the result is that I have a
vector map with a few areas, a few boundaries, a few centroids and a
lot of errors.

Is there a better way of approaching this? And how do I allow overlapping areas?

Regards
David
-------------- next part --------------
A non-text attachment was scrubbed...
Name: r.water.outlet.points.py
Type: text/x-python
Size: 3138 bytes
Desc: not available
Url : http://lists.osgeo.org/pipermail/grass-user/attachments/20100729/50304834/r.water.outlet.points.py