GRASS GIS manual: r.clump2

Note: This document is for an older version of GRASS GIS that is outdated. You should upgrade, and read the current addon manual page.

NAME

r.clump2 - Recategorizes data in a raster map by grouping cells that form physically discrete areas into unique categories.

KEYWORDS

raster, statistics, reclass

SYNOPSIS

r.clump2
r.clump2 help
r.clump2 [-e] input=name output=name [title=string] [coordinate=x,y[,x,y,...]] [--overwrite] [--verbose] [--quiet]

Flags:

-e: Ignore diagonal cells
--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=string: Title
coordinate=x,y[,x,y,...]: Map grid coordinates of starting points (E,N)

DESCRIPTION

r.clump2 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. Optionally r.clump2 uses start points and finds only those clumps where the start points are falling into.

Differences to r.clump

Category distinctions in the input raster map layer are NOT preserved. This means that if distinct category values are adjacent, they will be clumped together if possible.

Contrary to r.clump, NULL cells are ignored and not clumped.

r.clump2 also consideres diagonal cells. r.clump2 can be forced to consider only edge cells with the e flag, diagonal cells are now ignored.

Linear elements (lines that are a single cell wide) are without the e flag always clumped together.

NOTES

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

AUTHOR

Markus Metz

Last changed: $Date: 2011-11-08 13:56:45 -0800 (Tue, 08 Nov 2011) $

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