NAME
s.voronoi - Uses a GRASS sites list to produce a Voronoi
diagram
(GRASS Sites Program)
SYNOPSIS
s.voronoi [-aq] sites=name vect=name
[catnum=no|keep|gen]
[labels=no|cat|str,#|dec,#]
DESCRIPTION
s.voronoi uses an existing sites list (sites) to create a Voronoi
diagram (Thiessen polygons) in a binary vector file (vect).
OPTIONS
Parameters:
- sites=name
- Name of existing sites file.
- vect=name
- Name of the output file (binary vector file).
- catnum=no|keep|gen
- What to use as category numbers for the vector output: no
category numbers, keep from input file, or
generate as serial number.
options: no, keep, or gen
default: keep
- labels=no|cat|str,#|dec,#
- Site file field to use for generating the label. "#" is the n-th
string or decimal field associated with the site record.
- options: no; cat; str,#; or dec,#
- default: no
Flags:
- -a
- Use all sites found in the named sites file, rather than limiting output to sites falling within the current geographic region.
- -q
- Quiet. Cut out the chatter.
NOTES
s.voronoi can be run either non-interactively or interactively.
The program will be run non-interactively if the user specifies the name of
an existing site list file and a name for a vect file, using the form
s.voronoi [-aq] sites=name1 vect=name2 catnum=optCatnum labels=optLabel
where name1 is the name of an existing site list file and
name2 is the name of vector output file. optCatnum can be "keep" only
if the site file category number is integer. optLabel can
be "no", no labels; "cat", use site file category number as
label; str,num, use the num string type field of the site file as
label; or dec,num, use the num decimal type field of the site file as
label.
Alternately, the user can simply type s.voronoi on the
command line, without program arguments. In this case,
the user will be prompted for parameter values using the
standard GRASS parser interface described in the manual
entry for parser.
EXAMPLES
To create a Voronoi diagram keeping the original category number and using the
first decimal field as the output label use:
s.voronoi sites=inputSite vect=voro catnum=keep labels=dec,1
REFERENCES
Steve J. Fortune, (1987). A Sweepline Algorithm for
Voronoi Diagrams, Algorithmica 2, 153-174.
SEE ALSO
v.autocorr,
v.spag,
v.support,
s.delaunay,
s.hull,
s.sweep
AUTHOR
James Darrell McCauley, Purdue University
GRASS 5 update, improvements: Andrea
Aime, Modena, Italy
Last changed: $Date: 2003/03/09 07:40:16 $