r.describe(1)

1r.describe(1)                 Grass User's Manual                r.describe(1)
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NAME

6       r.describe   -  Prints  terse list of category values found in a raster
7       map layer.
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KEYWORDS

10       raster
11

SYNOPSIS

13       r.describe
14       r.describe help
15       r.describe [-1rndiq] map=name  [nv=string]   [nsteps=integer]   [--ver‐
16       bose]  [--quiet]
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18   Flags:
19       -1
20           Print the output one value per line
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22       -r
23           Only print the range of the data
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25       -n
26           Suppress reporting of any NULLs
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28       -d
29           Use the current region
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31       -i
32           Read fp map as integer
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34       -q
35           Run quietly
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37       --verbose
38           Verbose module output
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40       --quiet
41           Quiet module output
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43   Parameters:
44       map=name
45           Name of input raster map
46
47       nv=string
48           String representing no data cell value
49           Default: *
50
51       nsteps=integer
52           Number of quantization steps
53           Default: 255
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DESCRIPTION

56       r.describe  prints  a terse listing of category values found in a user-
57       specified raster map layer.
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59       r.describe ignores the current geographic region and  mask,  and  reads
60       the  full extent of the input raster map.  This functionality is useful
61       if the user intends to reclassify or  rescale  the  data,  since  these
62       functions  (r.reclass and r.rescale) also ignore the current geographic
63       region and mask.
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65       The nv parameter sets the string to be used to represent NULL values in
66       the module output; the default is '*'.
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68       The  nsteps  parameter  sets the number of quantisation steps to divide
69       into the input raster map.
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NOTES

72   FLAGS
73       If the user selects the -r flag, a range of category  values  found  in
74       the  raster  map layer will be printed. The range is divided into three
75       groups: negative, positive, and zero. If  negative  values  occur,  the
76       minimum and maximum negative values will be printed. If positive values
77       occur, the minimum and maximum positive values will be printed. If zero
78       occurs,  this  will  be  indicated. The range report will generally run
79       faster than the full list (the default output).
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81       The -d flag can be used to force  r.describe  to  respect  the  current
82       region  extents when repoting raster map categories. The default behav‐
83       ior is to read the full extent of the input raster map.
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85       If the -1 flag is specified,  the  output  appears  with  one  category
86       value/range per line.
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88       The -n flag suppresses the reporting of NULL values.
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EXAMPLES

91       The following examples are from the Spearfish60 sample Location:
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93       # Print the full list of raster map categories:
94       r.describe landcover.30m
95       * 11 21-23 31 32 41-43 51 71 81-83 85 91 92
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97
98       # Print the raster range only:
99       r.describe -r landcover.30m
100       11 thru 92
101       *
102        # Print raster map category range, suppressing nulls:
103       r.describe -n landcover.30m
104       11 21-23 31 32 41-43 51 71 81-83 85 91 92
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106
107       # Print raster map categories, one category per line:
108       r.describe -1 geology
109       *
110       1
111       2
112       3
113       4
114       5
115       6
116       7
117       8
118       9
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AUTHOR

125       Michael Shapiro, U.S. Army Construction Engineering Research Laboratory
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127       Last changed: $Date: 2008-02-21 03:02:34 +0100 (Thu, 21 Feb 2008) $
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129       Full index
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131       © 2003-2008 GRASS Development Team
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135GRASS 6.3.0                                                      r.describe(1)