1r3.neighbors(1)             GRASS GIS User's Manual            r3.neighbors(1)
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NAME

6       r3.neighbors   -  Makes  each  voxel value a function of the values as‐
7       signed to the voxels around it, and stores new voxel values in an  out‐
8       put 3D raster map
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KEYWORDS

11       raster3d, algebra, voxel, statistics, aggregation, neighbor, focal sta‐
12       tistics, filter
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SYNOPSIS

15       r3.neighbors
16       r3.neighbors --help
17       r3.neighbors  input=name  output=name  method=string   [quantile=float]
18       window=x,y,z  [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui]
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20   Flags:
21       --overwrite
22           Allow output files to overwrite existing files
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24       --help
25           Print usage summary
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27       --verbose
28           Verbose module output
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30       --quiet
31           Quiet module output
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33       --ui
34           Force launching GUI dialog
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36   Parameters:
37       input=name [required]
38           Name of input 3D raster map
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40       output=name [required]
41           Name for output 3D raster map
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43       method=string [required]
44           Aggregate operation
45           Options:  average,  median,  mode, minimum, maximum, range, stddev,
46           sum, count, variance,  diversity,  interspersion,  quart1,  quart3,
47           perc90, quantile
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49       quantile=float
50           Quantile to calculate for method=quantile
51           Options: 0.0-1.0
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53       window=x,y,z [required]
54           The  size of the window in x, y and z direction, values must be odd
55           integer numbers, eg: 3,3,3
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DESCRIPTION

58       r3.neighbors looks at each voxel in a 3D raster input  map  layer,  and
59       examines  the values assigned to the voxel in a user-defined "neighbor‐
60       hood" around it.  It outputs a new 3D raster map in which each voxel is
61       assigned  a  value that is a (user-specified) function of the values in
62       that voxel’s neighborhood.  For example, each voxel in the  output  map
63       might  be assigned a value equal to the average of the values appearing
64       in its 3 x 3 x 3 voxel "neighborhood" in the input map layer.
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66   OPTIONS
67       The user must specify the names of the 3D raster map layers to be  used
68       for  input  and  output, the method used to analyze neighborhood values
69       (i.e., the neighborhood function or operation to be performed), and the
70       moving window of the neighborhood.
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72       Neighborhood  Operation  Methods:  The neighborhood operators determine
73       what new value a center voxel in a neighborhood will have after examin‐
74       ing  values  inside  its neighboring voxels.  Each voxel in a 3D raster
75       map layer becomes the center voxel of a neighborhood as  the  neighbor‐
76       hood  window  moves  from  voxel  to  voxel  throughout  the map layer.
77       r3.neighbors can perform the following operations:
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79       average
80           The average value within the neighborhood.
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82       median
83           The value found half-way through a list of the neighborhood’s  val‐
84           ues, when these are ranged in numerical order.
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86       mode
87           The most frequently occurring value in the neighborhood.
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89       minimum
90           The minimum value within the neighborhood.
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92       maximum
93           The maximum value within the neighborhood.
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95       range
96           The range value within the neighborhood.
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98       stddev
99           The  statistical  standard deviation of values within the neighbor‐
100           hood.
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102       sum
103           The sum of values within the neighborhood.
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105       variance
106           The statistical variance of values within the neighborhood.
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108       diversity
109           The number of different values within the neighborhood.
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111       interspersion
112           The percentage of voxels containing values which  differ  from  the
113           values assigned to the center voxel in the neighborhood, plus 1.
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115       Neighborhood Size: The neighborhood moving window specifies which voxel
116       surrounding any given voxel fall into the neighborhood for that  voxel.
117       The  window  must  be three comma separated odd integers. The dimension
118       order is: x,y,z.  For example: the parameter window=3,3,3  specifies  a
119       moving window (a cube) with 27 voxel.
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NOTES

122       The r3.neighbors program works in the current geographic region.  It is
123       recommended, but not required, that the 3D resolution of the geographic
124       region be the same as that of the 3D raster map layer.
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126       r3.neighbors doesn’t propagate NULLs, but computes the aggregation over
127       the non-NULL voxels in the neighborhood.
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SEE ALSO

130        g.region, r.neighbors, r3.mapcalc, r3.stats, r3.support
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AUTHOR

133       Soeren Gebbert
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SOURCE CODE

136       Available at: r3.neighbors source code (history)
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138       Accessed: Saturday Oct 28 18:18:22 2023
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140       Main index | 3D raster index | Topics index | Keywords index |  Graphi‐
141       cal index | Full index
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143       © 2003-2023 GRASS Development Team, GRASS GIS 8.3.1 Reference Manual
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147GRASS 8.3.1                                                    r3.neighbors(1)