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=integer]   [cat=integer]   [step=integer]
       [--overwrite]  [--verbose]  [--quiet]

   Flags:
       --overwrite
           Allow output files to overwrite existing files

       --verbose
           Verbose module output

       --quiet
           Quiet module output

   Parameters:
       input=name
           Name of input vector map

       output=name
           Name for output vector map

       option=string
           Action to be taken
           Options: add
           Default: add

       layer=integer
           Layer number
           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 01:42:51 -0800 (Tue, 08 Nov 2011) $

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       © 2003-2013 GRASS Development Team

GRASS 6.4.3                                                                                  v.centroids(1grass)