[GRASSLIST:2875] finding downstream paths

[Christopher Fonnesbeck]

I am attempting to determine the downstream polyline for each reach in 
a stream network, so that I can route disturbances through the network 
(e.g. floods). I have tried determining the start and end point cats 
for each polyline using v.net with the report operation, but it shows 
each cat as zero:

1 0 0
2 0 0
3 0 0
...
2043 0 0
2044 0 0
2045 0 0
2046 0 0

Clearly this should not be the case. I have a contiguous network of 
polyline streams.

Any ideas here? Thanks,
C.
--
Christopher J. Fonnesbeck ( c h r i s @ f o n n e s b e c k . o r g )
Georgia Cooperative Fish & Wildlife Research Unit, University of Georgia