v.delaunay

Creates a Delaunay triangulation from an input vector map containing points or centroids.

Command linePython (grass.script)

v.delaunay [-rl] input=name [layer=string] output=name [--overwrite] [--verbose] [--quiet] [--qq] [--ui]

Example:

v.delaunay input=name output=name

grass.script.run_command("v.delaunay", input, layer="-1", output, flags=None, overwrite=False, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("v.delaunay", input="name", output="name")

Parameters

Command linePython (grass.script)

input=name [required]
    Name of input vector map
    Or data source for direct OGR access
layer=string
    Layer number or name ('-1' for all layers)
    A single vector map can be connected to multiple database tables. This number determines which table to use. When used with direct OGR access this is the layer name.
    Default: -1
output=name [required]
    Name for output vector map
-r
    Use only points in current region
-l
    Output triangulation as a graph (lines), not areas
--overwrite
    Allow output files to overwrite existing files
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

input : str, required
    Name of input vector map
    Or data source for direct OGR access
    Used as: input, vector, name
layer : str, optional
    Layer number or name ('-1' for all layers)
    A single vector map can be connected to multiple database tables. This number determines which table to use. When used with direct OGR access this is the layer name.
    Used as: input, layer
    Default: -1
output : str, required
    Name for output vector map
    Used as: output, vector, name
flags : str, optional
    Allowed values: r, l
    r
        Use only points in current region
    l
        Output triangulation as a graph (lines), not areas
overwrite: bool, optional
    Allow output files to overwrite existing files
    Default: False
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

v.delaunay uses an existing vector points map (input) to create a Delaunay triangulation vector map (output).

Delaunay triangulation example (red-yellow points are the data points from which the triangulation was generated):

EXAMPLE

Commands used with the North Carolina dataset to create the above figure (subset shown in figure).

g.region n=220750 s=219950 w=638300 e=639000 -p
v.delaunay input=elev_lid792_randpts output=elev_lid792_randpts_delaunay

REFERENCES

Leonid Guibas and Jorge Stolfi, (1985). Primitives for the Manipulation of General Subdivisions and the Computation of Voronoi Diagrams, ACM Transactions on Graphics, Vol 4, No. 2, April 1985, Pages 74-123

SEE ALSO

v.voronoi, v.hull

Delaunay triangulation (Wikipedia)

AUTHORS

Martin Pavlovsky, Google Summer of Code 2008, Student
Paul Kelly, Mentor
Based on "dct" by Geoff Leach, Department of Computer Science, RMIT.

SOURCE CODE

Available at: v.delaunay source code (history)
Latest change: Tuesday Feb 18 17:20:26 2025 in commit 688e625