1r3.neighbors(1) GRASS GIS User's Manual r3.neighbors(1)
2
6 r3.neighbors - Makes each voxel value a function of the values
7 assigned to the voxels around it, and stores new voxel values in an
8 output 3D raster map
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11 raster3d, algebra, voxel, statistics, aggregation, neighbor, focal sta‐
12 tistics, filter
13
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]
19 Flags:
21 --overwrite
22 Allow output files to overwrite existing files
23 --help
25 Print usage summary
26 --verbose
28 Verbose module output
29 --quiet
31 Quiet module output
32 --ui
34 Force launching GUI dialog
35 Parameters:
37 input=name [required]
38 Name of input 3D raster map
39 output=name [required]
41 Name for output 3D raster map
42 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
48 quantile=float
50 Quantile to calculate for method=quantile
51 Options: 0.0-1.0
52 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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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.
65 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.
71 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:
78 average
80 The average value within the neighborhood.
81 median
83 The value found half-way through a list of the neighborhood’s val‐
84 ues, when these are ranged in numerical order.
85 mode
87 The most frequently occurring value in the neighborhood.
88 minimum
90 The minimum value within the neighborhood.
91 maximum
93 The maximum value within the neighborhood.
94 range
96 The range value within the neighborhood.
97 stddev
99 The statistical standard deviation of values within the neighbor‐
100 hood.
101 sum
103 The sum of values within the neighborhood.
104 variance
106 The statistical variance of values within the neighborhood.
107 diversity
109 The number of different values within the neighborhood.
110 interspersion
112 The percentage of voxels containing values which differ from the
113 values assigned to the center voxel in the neighborhood, plus 1.
114 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.
120
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.
125 r3.neighbors doesn’t propagate NULLs, but computes the aggregation over
127 the non-NULL voxels in the neighborhood.
128
130 g.region
131 r.neighbors
132 r3.mapcalc
133 r3.stats
134 r3.support
135
137 Soeren Gebbert
138
140 Available at: r3.neighbors source code (history)
141 Main index | 3D raster index | Topics index | Keywords index | Graphi‐
143 cal index | Full index
144 © 2003-2020 GRASS Development Team, GRASS GIS 7.8.5 Reference Manual
146GRASS 7.8.5 r3.neighbors(1)