Note: A new GRASS GIS stable version has been released: GRASS GIS 7.4, available here.
Updated manual page: here
NAME
v.centroids - Adds missing centroids to closed boundaries.
KEYWORDS
vector,
centroid,
area
SYNOPSIS
v.centroids
v.centroids --help
v.centroids input=name output=name [option=string] [layer=string] [cat=integer] [step=integer] [--overwrite] [--help] [--verbose] [--quiet] [--ui]
Flags:
- --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
- output=name [required]
- Name for output vector map
- option=string
- Action to be taken
- Options: add
- Default: add
- layer=string
- Layer number or name
- Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.
- Default: 1
- cat=integer
- Category number starting value
- Default: 1
- step=integer
- Category increment
- Default: 1
GRASS defines vector areas as composite entities consisting of a set of
closed boundaries and a centroid. The attribute information associated
with that area is linked to the centroid. The
v.centroids module
adds centroids to closed boundaries in the
input file and assigns a
category number to them. The starting value as well as the increment size
may be set using optional parameters.
Multiple attributes may be linked to a single vector entity through
numbered fields referred to as layers. Refer to v.category
for more details, as v.centroids is simply a frontend to that
module.
The boundary itself is often stored without any category reference as it
can mark the border between two adjacent areas. Thus it would be ambiguous
as to which feature the attribute would belong. In some cases it may, for
example, represent a road between two parcels of land. In this case it
is entirely appropriate for the boundary to contain category information.
v.category
module: M. Hamish Bowman, Dept. Marine Science, Otago University, New Zealand
help page: Trevor Wiens
Last changed: $Date: 2011-11-08 13:24:20 -0800 (Tue, 08 Nov 2011) $
SOURCE CODE
Available at: v.centroids 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