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

DESCRIPTION

       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.

SEE ALSO

        v.category

AUTHORS

       module: M. Hamish Bowman, Dept. Marine Science, Otago University, New Zealand
       help page: Trevor Wiens

       Last changed: $Date: 2011-11-08 22:24:20 +0100 (Tue, 08 Nov 2011) $

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       © 2003-2016 GRASS Development Team, GRASS GIS 7.0.3 Reference Manual