NAMEr.clump - Recategorizes data in a raster map by grouping cells that form physically discrete areas into unique categories.
KEYWORDSraster, statistics, reclass
SYNOPSISr.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
DESCRIPTIONr.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.)
NOTESr.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 ALSOr.average r.buffer r.grow r.mapcalc r.mfilter r.neighbors r.to.vect r.reclass r.statistics r.support
AUTHORMichael Shapiro, U.S. Army Construction Engineering Research Laboratory Last changed: $Date: 2008-02-26 17:36:04 +0100 (Tue, 26 Feb 2008) $ Full index (C) 2003-2010 GRASS Development Team R.CLUMP(1)