NAME

       r.clump   -  Recategorizes  data  in  a  raster map by grouping cells that form physically
       discrete areas into unique categories.

KEYWORDS

       raster, statistics, reclass

SYNOPSIS

       r.clump
       r.clump help
       r.clump  [-q]  input=name  output=name   [title="string"]     [--overwrite]    [--verbose]
       [--quiet]

   Flags:
       -q
           Run quietly

       --overwrite
           Allow output files to overwrite existing files

       --verbose
           Verbose module output

       --quiet
           Quiet module output

   Parameters:
       input=name
           Name of input raster map

       output=name
           Name for output raster map

       title=
           Title for output raster map

DESCRIPTION

       r.clump  finds  all areas of contiguous cell category values in the input raster map layer
       name. It assigns a unique category value to each such  area  ("clump")  in  the  resulting
       output  raster  map  layer  name.  Category distinctions in the input raster map layer are
       preserved.  This means that if distinct category values are adjacent,  they  will  NOT  be
       clumped  together.   (The user can run <A HREF="r.reclass.html">r.reclass prior to r.clump
       to recategorize cells and reassign cell category values.)

NOTES

       r.clump moves a 2x2 matrix over the input raster map layer.  The lower  right-hand  corner
       of the matrix is grouped with the cells above it, or to the left of it (diagonal cells are
       not considered.)

       r.clump works properly with raster map layers that contain only "fat" areas (more  than  a
       single cell in width).  Linear elements (lines that are a single cell wide) may or may not
       be clumped together depending on the direction of the line - horizontal and vertical lines
       of  cells  are considered to be contiguous, but diagonal lines of cells are not considered
       to be contiguous and are broken up into separate clumps.

       A random color table and other support files are  generated  for  the  output  raster  map
       layer.

SEE ALSO

       r.average
       r.buffer
       r.grow
        r.mapcalc
       r.mfilter
       r.neighbors
       r.to.vect
       r.reclass
       r.statistics
       r.support

AUTHOR

       Michael Shapiro, U.S. Army Construction Engineering Research Laboratory

       Last changed: $Date: 2008-02-26 08:36:04 -0800 (Tue, 26 Feb 2008) $

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       © 2003-2013 GRASS Development Team