1r.statistics(1) Grass User's Manual r.statistics(1)
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6 r.statistics - Calculates category or object oriented statistics.
7
9 raster, statistics, zonal statistics
10
12 r.statistics
13 r.statistics --help
14 r.statistics [-c] base=name cover=name method=string output=name
15 [--overwrite] [--help] [--verbose] [--quiet] [--ui]
16 Flags:
18 -c
19 Cover values extracted from the category labels of the cover map
20 --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 base=name [required]
38 Name of base raster map
39 cover=name [required]
41 Name of cover raster map
42 method=string [required]
44 Method of object-based statistic
45 Options: diversity, average, mode, median, avedev, stddev, vari‐
46 ance, skewness, kurtosis, min, max, sum
47 diversity: Diversity of values in specified objects in %%
48 average: Average of values in specified objects
49 mode: Mode of values in specified objects
50 median: Median of values in specified objects
51 avedev: Average deviation of values in specified objects
52 stddev: Standard deviation of values in specified objects
53 variance: Variance of values in specified objects
54 skewness: Skewnes of values in specified objects
55 kurtosis: Kurtosis of values in specified objects
56 min: Minimum of values in specified objects
57 max: Maximum of values in specified objects
58 sum: Sum of values in specified objects
59 output=name [required]
61 Resultant raster map
62
64 r.statistics is a tool to analyse exploratory statistics of a categori‐
65 cal "cover layer" according to how it intersects with objects in a
66 "base layer". A variety of standard statistical measures are possible
67 (called "zonal statistics" in some GIS). All cells in the base layer
68 are considered one object for the analysis. For some applications, one
69 will first want to prepare the input data so that all areas of contigu‐
70 ous cell category values in the base layer are uniquely identified,
71 which can be done with r.clump.
72 The available methods are the following:
73 · average deviation
75 · average
77 · diversity
79 · kurtosis
81 · maximum
83 · median
85 · minimum
87 · mode
89 · skewness
91 · standard deviation
93 · sum
95 · variance
97 The calculations will be performed on each area of data of the cover
98 layers which fall within each unique value, or category, of the base
99 layer.
100 Setting the -c flag the category labels of the covering raster layer
102 will be used. This is nice to avoid the GRASS limitation to integer in
103 raster maps because using category values floating point numbers can be
104 stored.
105 All calculations create an output layer. The output layer is a reclas‐
107 sified version of the base layer with identical category values, but
108 modified category labels - the results of the calculations are stored
109 in the category labels of the output layer.
110
112 For floating-point cover map support, see the alternative
113 r.stats.zonal. For quantile calculations with support for float‐
114 ing-point cover maps, see the alternative r.stats.quantile.
115
117 Calculation of average elevation of each field in the Spearfish region:
118 r.statistics base=fields cover=elevation.dem out=elevstats method=average
119 r.category elevstats
120 r.mapcalc "fieldelev = @elevstats"
121 r.univar fieldelev
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124 r.category, r.clump, r.mode, r.mapcalc, r.neighbors, r.stats.quantile,
125 r.stats.zonal, r.univar
126
128 Martin Schroeder, Geographisches Institut Heidelberg, Germany
129 Last changed: $Date: 2017-01-19 14:35:33 +0100 (Thu, 19 Jan 2017) $
131
133 Available at: r.statistics source code (history)
134 Main index | Raster index | Topics index | Keywords index | Graphical
136 index | Full index
137 © 2003-2019 GRASS Development Team, GRASS GIS 7.6.0 Reference Manual
139GRASS 7.6.0 r.statistics(1)