r.reclass.area(1)

NAME
r.reclass.area - Reclasses a raster map greater or less than user specified area size (in hectares).

KEYWORDS
raster, statistics, aggregation

SYNOPSIS
r.reclass.area
r.reclass.area --help
r.reclass.area [-cd] input=name output=name value=float mode=string [method=string] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

  Flags:

-c
    Input map is clumped

-d
    Clumps including diagonal neighbors

--overwrite
    Allow output files to overwrite existing files

--help
    Print usage summary

--verbose
    Verbose module output

--quiet
    Quiet module output

--ui
    Force launching GUI dialog

  Parameters:

input=name [required]
    Name of input raster map

output=name [required]
    Name for output raster map

value=float [required]
    Value option that sets the area size limit (in hectares)

mode=string [required]
    Lesser or greater than specified value
    Options: lesser, greater

method=string
    Method used for reclassification
    Options: reclass, rmarea
    Default: reclass

DESCRIPTION
r.reclass.area reclasses a raster map greater or less than a user specified area size (in hectares).

If the -c flag is used, r.reclass.area will skip the creation of a clumped raster and assume that the input raster is already clumped.

EXAMPLES
In this example, the ZIP code map in the North Carolina sample dataset is filtered for large areas (removing smaller areas from the map).

g.region raster=zipcodes -p
r.report zipcodes unit=h

Extract only areas greater than 2000 ha, NULL otherwise:

r.reclass.area input=zipcodes output=zipcodes_larger2000ha mode=greater value=2000
r.report zipcodes_larger2000ha unit=h

Figure: r.reclass.area method=reclass In this example, the ZIP code map in the North Carolina sample dataset is filtered for smaller areas which are substituted with the value of the respective adjacent area with largest shared boundary. Reclass by substitutional removing of areas minor of 1000 ha:

r.reclass.area input=zipcodes output=zipcodes_minor1000ha mode=lesser value=1000 method=rmarea

Figure: r.reclass.area method=rmarea

SEE ALSO
r.reclass, r.clump, r.stats

AUTHORS
NRCS,
Markus Neteler

SOURCE CODE

Available at: r.reclass.area source code (history)

Accessed: Wednesday Feb 04 01:05:40 2026

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