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<h2>NAME</h2>
<em><b>v.delaunay</b></em> - Creates a Delaunay triangulation from an input vector map containing points or centroids.
<h2>KEYWORDS</h2>
vector
<h2>SYNOPSIS</h2>
<b>v.delaunay</b><br>
<b>v.delaunay help</b><br>
<b>v.delaunay</b> [-<b>rl</b>] <b>input</b>=<em>name</em> <b>output</b>=<em>name</em> [--<b>overwrite</b>] [--<b>verbose</b>] [--<b>quiet</b>]
<h3>Flags:</h3>
<DL>
<DT><b>-r</b></DT>
<DD>Use only sites in current region</DD>
<DT><b>-l</b></DT>
<DD>Output triangulation as a graph (lines), not areas</DD>
<DT><b>--overwrite</b></DT>
<DD>Allow output files to overwrite existing files</DD>
<DT><b>--verbose</b></DT>
<DD>Verbose module output</DD>
<DT><b>--quiet</b></DT>
<DD>Quiet module output</DD>
</DL>
<h3>Parameters:</h3>
<DL>
<DT><b>input</b>=<em>name</em></DT>
<DD>Name of input vector map</DD>
<DT><b>output</b>=<em>name</em></DT>
<DD>Name for output vector map</DD>
</DL>
<H2>DESCRIPTION</H2>
<EM>v.delaunay</EM> uses an existing vector points map (<B>input</B>) to create a
Delaunay triangulation vector map (<B>output</B>).
<P>
<BR>
Delaunay triangulation and Voronoi diagram example:
<center>
<img src=v_voronoi_delaunay.png border=1><BR>
<table border=0 width=590>
<tr><td><center>
<i>Delaunay Triangulation (left pane), Voronoi diagram (center pane),
and both (right pane)</i>
</center></td></tr>
</table>
</center>
<H2>EXAMPLE</H2>
Commands used with the Spearfish dataset to create the above figure.
<div class="code"><pre>
g.region n=4927250 s=4919400 w=588650 e=594850
d.frame -c fr=one at=0,100,0,33.3333
d.frame -c fr=two at=0,100,33.3333,66.6667
d.frame -c fr=three at=0,100,66.6667,100
v.delaunay -lr in=archsites out=arch_delaunay
d.frame -s one
d.vect arch_delaunay
d.vect archsites color=red fcolor=red size=5 icon=basic/circle
v.voronoi -l in=archsites out=arch_voronoi
d.frame -s two
d.vect arch_voronoi type=line
d.vect archsites color=red fcolor=red size=5 icon=basic/circle
d.frame -s three
d.vect arch_voronoi type=line
d.vect arch_delaunay color=blue
d.vect archsites color=red fcolor=red size=5 icon=basic/circle
</pre></div>
<H2>REFERENCES</H2>
<EM>Steve J. Fortune, (1987). A Sweepline Algorithm for
Voronoi Diagrams, Algorithmica 2, 153-174.</EM>
<H2>SEE ALSO</H2>
<EM>
<A HREF="v.voronoi.html">v.voronoi</A>,
<A HREF="v.hull.html">v.hull</A>,
</EM>
<H2>AUTHORS</H2>
James Darrell McCauley, Purdue University<br>
GRASS 5 update, improvements: <a href=mailto:aaime@libero.it>Andrea Aime</a>, Modena, Italy<br>
GRASS 5.7 update: Radim Blazek
<p><i>Last changed: $Date: 2006-05-24 10:51:52 +0200 (Wed, 24 May 2006) $</i></p>
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