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, in quotes
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 17:36:04 +0100 (Tue, 26 Feb 2008) $
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© 2003-2011 GRASS Development Team
