1r.circle(1) Grass User's Manual r.circle(1)
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6 r.circle - Creates a raster map containing concentric rings around a
7 given point.
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10 raster
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13 r.circle
14 r.circle help
15 r.circle [-b] output=name coordinate=x,y [min=float] [max=float]
16 [mult=float] [--overwrite] [--verbose] [--quiet]
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18 Flags:
19 -b
20 Generate binary raster map
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22 --overwrite
23 Allow output files to overwrite existing files
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25 --verbose
26 Verbose module output
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28 --quiet
29 Quiet module output
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31 Parameters:
32 output=name
33 Name for output raster map
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35 coordinate=x,y
36 The coordinate of the center (east,north)
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38 min=float
39 Minimum radius for ring/circle map (in meters)
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41 max=float
42 Maximum radius for ring/circle map (in meters)
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44 mult=float
45 Multiplier
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48 This module creates an output raster map centered on the x,y values
49 specified with the coordinate parameter, out to the edge of the current
50 region. The output cell values increase linearly from the specified
51 center. The min and max parameters control the inner and outer output
52 raster map radii, respectively.
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54 The mult parameter can be used to multiply the output raster cells by a
55 common factor. Note that this parameter does not affect the output
56 raster position or size; only the z-values are changed with this param‐
57 eter.
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59 Binary-output raster maps (solid circles of one value) can be created
60 with the -b flag. Raster maps so created can be used to create binary
61 filters for use in i.ifft (inverse Fourier transformations; apply fil‐
62 ter with r.mask).
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65 Generate a raster circle at current map center with a radius of 300m
66 and outwardly increasing raster values:
67 EASTCENTER=`g.region -c | awk ' /center easting:/ { print $3 }'`
68 NORTHCENTER=`g.region -c | awk ' /center northing:/ { print $3 }'`
69 r.circle output=circle coordinate=${EASTCENTER},${NORTHCENTER} max=300
70 Generate a binary raster ring around current map center with an inner
71 radius of 500m and an outer radius of 1000m:
72 EASTCENTER=`g.region -c | awk ' /center easting:/ { print $3 }'`
73 NORTHCENTER=`g.region -c | awk ' /center northing:/ { print $3 }'`
74 r.circle -b output=circle coordinate=${EASTCENTER},${NORTHCENTER}
75 min=500 max=1000
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79 g.region, g.remove, g.rename, i.fft, i.ifft, r.mask
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82 Bill Brown, U.S. Army Construction Engineering Research Laboratory
83 Additional flag/min/max parameter by Markus Neteler, University of Han‐
84 nover
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86 Last changed: $Date: 2008-01-22 15:21:36 +0100 (Tue, 22 Jan 2008) $
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88 Full index
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90 © 2003-2008 GRASS Development Team
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94GRASS 6.3.0 r.circle(1)