Novice: Contours from GIF [Smoothing]
cameron at stl.dec.com
Thu Sep 25 02:56:24 EDT 1997
Radoslav Bonk wrote:
> [...] try to run d.display [...]
Wow! I hadn't found that program yet. That makes things much simpler,
Aldo Clerici wrote:
> I usually use:
> r.thin (to thins lines)
> r.line (to create a binary vector file)
> v.support (to build the dig_plus file)
> v.digit (to label contour lines).
Okay, I've done all that now. I've also gone further and attempted
to use v.surf.idw to build a raster, then r.neighbors to smooth the
data, then r.slope.aspect and then r.cost to try and figure out an
optimal road path. [Thanks to Ishmael Williams for that last bit].
But the contour separation varies considerably ... the land has steep
and flat sections, so r.neighbors would tend to pull down the hills
if I enlarge it's sampling area too much ... but if I don't enlarge
it enough then there are flat sections between contours that affect
the cost calculations.
How do I smooth contours without warping the data too much?
James Cameron (cameron at stl.dec.com)
Digital Equipment Corporation (Australia) Pty. Ltd. A.C.N. 000 446 800
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