1r3.to.rast(1) GRASS GIS User's Manual r3.to.rast(1)
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6 r3.to.rast - Converts 3D raster maps to 2D raster maps
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9 raster3d, conversion, raster, voxel
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12 r3.to.rast
13 r3.to.rast --help
14 r3.to.rast [-mr] input=string output=string [type=string] [multi‐
15 ply=float] [add=float] [--overwrite] [--help] [--verbose]
16 [--quiet] [--ui]
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18 Flags:
19 -m
20 Use 3D raster mask (if exists) with input map
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22 -r
23 Use the same resolution as the input 3D raster map for the 2D out‐
24 put maps, independent of the current region settings
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26 --overwrite
27 Allow output files to overwrite existing files
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29 --help
30 Print usage summary
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32 --verbose
33 Verbose module output
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35 --quiet
36 Quiet module output
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38 --ui
39 Force launching GUI dialog
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41 Parameters:
42 input=string [required]
43 3D raster map(s) to be converted to 2D raster slices
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45 output=string [required]
46 Basename for resultant raster slice maps
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48 type=string
49 Type of raster map to be created
50 Storage type for resultant raster map
51 Options: CELL, FCELL, DCELL
52 CELL: Integer
53 FCELL: Single precision floating point
54 DCELL: Double precision floating point
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56 multiply=float
57 Value to multiply the raster values with
58 Coefficient a in the equation y = ax + b
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60 add=float
61 Value to add to the raster values
62 Coefficient b in the equation y = ax + b
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65 Converts one 3D raster map into several 2D raster maps (depends on
66 depths). If the 2D and 3D region settings are different, the 3D reso‐
67 lution will be adjusted to the 2D resolution (the depths are not
68 touched). The user can force r3.to.rast to use the 2D resolution of
69 the input 3D raster map for the output maps, independently from the
70 current region settings.
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72 How r3.to.rast works
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75 Map type conversions
76 Type of resulting 2D raster maps is determined by the type of the input
77 3D raster, i.e. 3D raster of type DCELL (double) will result in DCELL
78 2D rasters. A specific type for 2D rasters can be requested using the
79 type option.
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81 The type option is especially advantageous when the 3D raster map
82 stores categories (which need to be stored as floating point numbers)
83 and the 2D raster map should be also categorical, i.e. use integers.
84 The type is set to CELL in this case.
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86 Modifying the values
87 The values in the 3D raster map can be modified prior to storing in the
88 2D raster map. The values can be scaled using the option multiply and a
89 constant value can be added using the option add. The new value is
90 computed using the following equation:
91 y = ax + b
92 where x is the original value, a is the value of multiply option, b is
93 the value of add option, and y is the new value. When multiply is not
94 provided, the value of a is 1. When add is not provided, the value of b
95 is 0.
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98 Every slice of the 3D raster map is copied to one 2D raster map. The
99 maps are named like output_slicenumber. Slices are counted from bottom
100 to the top, so the bottom slice has number 1.
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102 The number of slices is equal to the number of depths.
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104 To round floating point values to integers when using type=CELL, the
105 add option should be set to 0.5.
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108 r3.cross.rast, r3.out.vtk, r3.out.ascii, g.region
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111 Sören Gebbert Vaclav Petras, NCSU GeoForAll Lab
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114 Available at: r3.to.rast source code (history)
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116 Accessed: Saturday Oct 28 18:18:24 2023
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118 Main index | 3D raster index | Topics index | Keywords index | Graphi‐
119 cal index | Full index
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121 © 2003-2023 GRASS Development Team, GRASS GIS 8.3.1 Reference Manual
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125GRASS 8.3.1 r3.to.rast(1)