1v.voronoi(1) Grass User's Manual v.voronoi(1)
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6 v.voronoi - Create a Voronoi diagram from an input vector map contain‐
7 ing points or centroids.
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10 vector
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13 v.voronoi
14 v.voronoi help
15 v.voronoi [-lt] input=name output=name [--overwrite]
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17 Flags:
18 -l Output tessellation as a graph (lines), not areas
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20 -t Do not create attribute table
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22 --overwrite
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24 Parameters:
25 input=name
26 Name of input vector map
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28 output=name
29 Name for output vector map
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32 v.voronoi uses an existing vector points map (input) to create a
33 Voronoi diagram (Thiessen polygons) in a new vector map (output).
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35 Voronoi diagram and Delaunay triangulation example: | Delaunay Triangu‐
36 lation (left pane), Voronoi diagram (center pane), and both (right
37 pane)
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40 Voronoi diagrams may be used for nearest-neighbor flood filling. Give
41 the centroids attributes (start with v.db.addcol), then optionally con‐
42 vert to a raster map with v.to.rast.
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45 Commands used with the Spearfish dataset to create the above figure.
46 g.region n=4927250 s=4919400 w=588650 e=594850
47 d.frame -c fr=one at=0,100,0,33.3333
48 d.frame -c fr=two at=0,100,33.3333,66.6667
49 d.frame -c fr=three at=0,100,66.6667,100
50 v.delaunay -lr in=archsites out=arch_delaunay
51 d.frame -s one
52 d.vect arch_delaunay
53 d.vect archsites color=red fcolor=red size=5 icon=basic/circle
54 v.voronoi -l in=archsites out=arch_voronoi
55 d.frame -s two
56 d.vect arch_voronoi type=line
57 d.vect archsites color=red fcolor=red size=5 icon=basic/circle
58 d.frame -s three
59 d.vect arch_voronoi type=line
60 d.vect arch_delaunay color=blue
61 d.vect archsites color=red fcolor=red size=5 icon=basic/circle
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65 Only attribute table of field 1 is copied.
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68 Steve J. Fortune, [4m(1987). A Sweepline Algorithm for Voronoi Diagrams,
69 Algorithmica 2, 153-174.
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72 v.delaunay, v.hull,
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75 James Darrell McCauley, Purdue University
76 GRASS 5 update, improvements: Andrea Aime, Modena, Italy
77 GRASS 5.7 update: Radim Blazek
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79 Last changed: $Date: 2006/05/24 08:51:52 $
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81 Full index
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85GRASS 6.2.2 v.voronoi(1)