[GRASSLIST:1477] small raster regions elimination

Rado Bonk rado at cosmos.dsc.unomaha.edu
Wed Feb 21 03:22:24 EST 2001

Hi GRASS users, 
After mulptiply overlay operations, there are several
(hundreds) raster regions with the area too small for analysis. I would
like to eliminate these regions and append them to the adjacent regions
based on the length of its common boundary (that would be the best).
r.reclass.area script does a nice job with elimination of these regions by
assigning the area of the smallest region, and deleting all regions with
area smaller than assigned value. (Markus, there is an error in
line 9, missing || operand, see correct line at the end of the message).

The task can be solved by exporting raster regions into vector, and than
using vector algebra in some of the desktop mapping systems. However, I
would like to avoid this, and I would like to use raster data
format. Maybe some filter would help.

There was similar question a time ago concerning "inward
buffering" operation with no response.

Thanks for any hints.
	-Rado Bonk

r.reclass.area (all in one line)
if ( test "$1" = "help" ) || ( test "$1" = "" ) || ( test "$1" = 
"-help" ); then	                                ^^         		

Rado Bonk
Geography and Geology
UNO, Omaha, NE 68182-0199
rado at cosmos.unomaha.edu

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