[GRASSLIST:846] Re: interpolations: vector output

[H Bowman]

> How to interpolate from sites data directly to vector isolines 
> (isobathes, etc...) ?
> Is there a simple way to do this without any intermediate
> interpolation to a raster file ?

I think you do have to go through the step of making a 3d model surface
first with s.surf.rst, s.surf.idw, or s.surf.krig(?) and then run
r.contour.

Maybe what you are asking for is how to make a 3d vector surface (TIN)
using delaunay triangulation? You'd need to use GRASS 5.1 for that -  I
am not sure if the functionality yet exists, but it should be possible
to make the surface. You'd then still need a r.contour-like program to
create the contours and the results probably wouldn't look very good.

For topographic contours or isobaths I think s.surf.rst and r.contour
would give the best results within GRASS.

You might be able to make a vector contour file with other software such
as GRI or GMT ?
http://gri.sourceforge.net
http://gmt.soest.hawaii.edu
maybe not.


Hamish