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Note: A new GRASS GIS stable version has been released: GRASS GIS 7.4, available here.
Updated manual page: here

NAME

v.qcount - Indices for quadrat counts of vector point lists.

KEYWORDS

vector, statistics, point pattern

SYNOPSIS

v.qcount
v.qcount --help
v.qcount [-g] input=name [layer=string] [output=name] nquadrats=integer radius=float [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-g
Print results in shell script style
--overwrite
Allow output files to overwrite existing files
--help
Print usage summary
--verbose
Verbose module output
--quiet
Quiet module output
--ui
Force launching GUI dialog

Parameters:

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
Name for output quadrat centers map (number of points is written as category)
nquadrats=integer [required]
Number of quadrats
radius=float [required]
Quadrat radius

Table of contents

DESCRIPTION

v.qcount chooses nquadradius ants circular quadrats of radius radius such that they are completely within the bounds of the current region and no two quadrats overlap. The number of points falling within each quadrat are counted and indices are calculated to estimate the departure of point locations from complete spatial randomness.

NOTES

This program may not work properly with lat-long data. It uses hypot() in two files: count.c and findquads.c.

SEE ALSO

v.random

REFERENCES

General references include:

References to the indices include:

KNOWN ISSUES

Timestamp not working for header part of counts output. (2000-10-28)

AUTHORS

James Darrell McCauley <darrell@mccauley-usa.com>,
when he was at: Agricultural Engineering Purdue University

Modified for GRASS 5.0 by Eric G. Miller (2000-10-28)
Modified for GRASS 5.7 by R. Blazek (2004-10-14)

Last changed: $Date: 2015-05-10 17:16:13 -0700 (Sun, 10 May 2015) $

SOURCE CODE

Available at: v.qcount source code (history)


Note: A new GRASS GIS stable version has been released: GRASS GIS 7.4, available here.
Updated manual page: here

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© 2003-2018 GRASS Development Team, GRASS GIS 7.0.7svn Reference Manual