[GRASS-user] distance along flow line to a particular feature

[Maciej Sieczka]

Godard Vincent napisa?(a):
> Hi Grass users,
> I am quite new to Grass and I come here to get some hints and guidelines about 
> a particular problem I have. 
> I work on a watershed (on which I ran r.watershed, to get flow directions, 
> accumulation...) and inside this watershed I define a linear feature (raster 
> or vector) as the main stream.
> I would like to calculate the distance (along the hydrographic network) of 
> each pixel of this watershed to the main stream. By distance I mean lenght 
> calculated along the flow lines defined by the flow directions. The desired 
> final output is a raster containing that distance to the main stream.
> Has anybody done such a thing with Grass previously?

Markus Neteler has done something similar to what you describe.

http://grass.itc.it/grass60/screenshots/raster.php

(the "distance to water" one")

If that' what you mean, try asking him.

Maciek