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voronoiDiagram

Voronoi diagram of Delaunay triangulation

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Syntax

[V,r] = voronoiDiagram(DT)

Description

[V,r] = voronoiDiagram(DT) returns the Voronoi vertices V and the Voronoi regions r of the points in a Delaunay triangulation. Each region in r represents the points surrounding a triangulation vertex that are closer to that vertex than any other vertex in the triangulation. The collection of Voronoi regions make up a Voronoi diagram.

example

Examples

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Open Live Script

Compute the Voronoi vertices and regions of a 2-D Delaunay triangulation.

Create a Delaunay triangulation from a set of 2-D points. 

P = [ 0.5    0
      0      0.5
     -0.5   -0.5
     -0.2   -0.1
     -0.1    0.1
      0.1   -0.1
      0.1    0.1 ];
DT = delaunayTriangulation(P);

Compute the Voronoi vertices and regions. 

[V,r] = voronoiDiagram(DT);

Display the connectivity of the Voronoi region associated with the 3rd point in the triangulation. 

r{3}
ans = 1×4

     1     6    10     3

Display the coordinates of the Voronoi vertices bounding the 3rd region. The Inf values indicate that the region contains points on the convex hull. 

V(r{3},:)
ans = 4×2

       Inf       Inf
    0.7000   -1.6500
   -0.0500   -0.5250
   -1.7500    0.7500

Input Arguments

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Delaunay triangulation, specified as a scalar delaunayTriangulation object.

Data Types: delaunayTriangulation

Output Arguments

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Voronoi vertices, returned as a 2-column matrix (2-D) or a 3-column matrix (3-D). Each row of V contains the coordinates of a Voronoi vertex.

The Voronoi regions associated with points that lie on the convex hull of the triangulation vertices are unbounded. Bounding edges of these regions radiate to infinity. The first vertex in V represents the vertex at infinity and is designated with Inf.

Data Types: double

Voronoi regions, returned as a cell array whose elements contain the connectivity of the Voronoi vertices in V. The points in each row of r form the bounding region associated with the corresponding row in the Points property.

Data Types: double

Extended Capabilities

Thread-Based Environment
Run code in the background using MATLAB® backgroundPool or accelerate code with Parallel Computing Toolbox™ ThreadPool.

Version History

Introduced in R2013a

See Also