[GRASS-user] Creating vector lines from vector or raster points

[Nikos Alexandris]

Lee Eddington wrote:
> > I'd like to create vector lines from vector or raster point data.  I have
> > rasters of x and y wind components and have used r.mapcalc to compute the
> > x and y values of the original raster grid points and the x and y values
> > for displacements points due to the wind speed and direction.  I'd like to
> > take these x and y location values in these rasters and create vector
> > lines that connect the original x,y grid points to the displacement 
> > points.  I can create vector points with these values at the gird points
> > using r.to.vect, but not sure how to create new vector lines with the
> > info.

Nikos:
> Does the m.cogo module help? See:
> 
> http://grass.osgeo.org/grass64/manuals/m.cogo.html  OR
> http://grass.osgeo.org/grass70/manuals/m.cogo.html

+ something like the following perhaps:

http://casoilresource.lawr.ucdavis.edu/drupal/node/989

N