[GRASS-user] Help needed for ascii point export

[Vincent Bain]

Hi,

don't know how many points you have to handle along the stream, so the
next solution may not be acceptable :

the idea is to digitize a polyline along your point set in a new map,
respecting the stream direction. Vertices are digitized to "roughly"
meet the existing background points, then v.edit would do the rest like
this (according to e.g. a 6 units snapping threshold) :

v.edit map=streamline type=line tool=move move=0,0 thres=-1,6,0
where="cat>0" bgmap=streampoints snap=vertex

finally v.out.ascii on map streamline.

Yours,
Vincent


Le mardi 15 avril 2014 à 08:13 +0200, jctorres a écrit :
> Hello
> 
> You can create a map of these points contining the elevation as
> attribute. Once you output this map you could sort points using the
> elevation values.
> 
> you can do this for instance using v.to.rast to convert the points to
> raster, them combine this map with elevation using r.mapcalc
> (assigning elevation to the points), and them output the map using
> r.out.xyz.
> To sort the points you can use any sort program or a spreadsheet.
> 
> 
> Best regards
> 
> Juan Carlos Torres
> 
> El 15/04/14 04:52, Thomas Adams escribió:
> 
> > All: 
> > 
> > 
> > I have a collection of points that represent the centerline of a
> > river. I need to output them in upstream to downstream order (or the
> > reverse). A simple v.out.ascii does not do this because of the
> > channel meanders. It's critical to get the x,y locations of these
> > points in the correct order.
> > 
> > 
> > Any help is appreciated!
> > 
> > 
> > Regards,
> > Tom
> > 
> > 
> > -- 
> > 
> > 
> > 
> > 
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> 
> -- 
> 
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