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Glynn Clements wrote:
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cite="mid:18835.51452.481786.74926@cerise.gclements.plus.com"
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<pre wrap="">Dylan Beaudette wrote:
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<pre wrap="">While we are on this topic, is there a way to get a weigthed voronoi
diagram using grass ?
The ability to rank a point to tune the area's influence would be great,
for that purpose I've been using an arcgis'extension* but with grass it
is not possible**. Is there a way to get a similar result ?
*<a class="moz-txt-link-freetext" href="http://www.geog.unt.edu/~pdong/software.htm">http://www.geog.unt.edu/~pdong/software.htm</a>
**<a class="moz-txt-link-freetext" href="http://osdir.com/ml/gis.grass.user/2004-04/msg00036.html">http://osdir.com/ml/gis.grass.user/2004-04/msg00036.html</a>
Regards,
MORREALE Jean Roc
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<pre wrap="">Now that I have read about 'weighted voronoi diagrams', I wonder if a
combination of r.cost + r.mapcalc would solve this problem. Something
along those lines is demonstrated here:
<a class="moz-txt-link-freetext" href="http://casoilresource.lawr.ucdavis.edu/drupal/node/288">http://casoilresource.lawr.ucdavis.edu/drupal/node/288</a>
This example isn't quite what is requested, although using r.cost with
start=point_i, and stop=neighbor_points (derived from v.delaunay /
v.distance?) may work. It would then be a little more work to convert
the weighted-distance rasters into polygons, and link back to the
original attribute tables... but (hopefully) not outside the realm of
possibility via a script.
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<pre wrap=""><!---->
The problem with using r.cost is that you would need to know the cost
for each cell before you have created the polygons.
I think that the simplest accurate approach would be to modify
r.grow.distance.
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Do you mean: adding a metric parameter to Euclidean, Squared,
Manhattan, and Maximum? Something like: compute on the basis of the
value of traversed cells?<br>
<br>
Jan<br>
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