NAME

       r.resamp.stats  - Resamples raster map layers to a coarser grid using aggregation.

KEYWORDS

       raster, resample

SYNOPSIS

       r.resamp.stats
       r.resamp.stats help
       r.resamp.stats [-nw] input=name output=name  [method=string]   [--overwrite]  [--verbose]  [--quiet]

   Flags:
       -n
           Propagate NULLs

       -w
           Weight according to area (slower)

       --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

       method=string
           Aggregation method
           Options: average,median,mode,minimum,maximum,quart1,quart3,perc90,sum,variance,stddev
           Default: average

DESCRIPTION

       r.resamp.stats  fills  a  grid  cell (raster) matrix with aggregated values generated from a set of input
       layer data points.

       Without the -w switch, the aggregate is computed over all of the input cells whose centers lie within the
       output cell.

       With the -w switch, the aggregate uses the values from all input cells which intersect the  output  cell,
       weighted  according  to  the  proportion  of  the  source cell which lies inside the output cell. This is
       slower, but produces a more accurate result.

NOTES

       Resampling modules (r.resample, r.resamp.stats, r.resamp.interp, r.resamp.rst) resample the map to  match
       the current region settings.

       The notion of weighting doesn't make any sense for the min and max aggregates. However, the -w flag still
       has  significance  in  that,  when  multiple  destination cells overlap a source cell, the source cell is
       included in the calculation of all of the destination cells.

EXAMPLE

       Resample elevation raster map to a lower resolution (from 6m to 20m; North Carolina sample dataset):
       g.region rast=el_D782_6m -p
       g.region res=20 -ap
       r.resamp.stats input=el_D782_6m output=el_D782_20m

SEE ALSO

       g.region, r.resample, r.resamp.rst r.resamp.interp

AUTHOR

       Glynn Clements

       Last changed: $Date: 2011-11-08 03:29:50 -0800 (Tue, 08 Nov 2011) $

       Full index

       © 2003-2013 GRASS Development Team

GRASS 6.4.3                                                                               r.resamp.stats(1grass)