1v.colors(1) Grass User's Manual v.colors(1)
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6 v.colors - Creates/modifies the color table associated with a vector
7 map.
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10 vector, color table
11
13 v.colors
14 v.colors --help
15 v.colors [-rwldngac] map=name [layer=string] use=string [col‐
16 umn=name] [range=min,max] [color=style] [raster=name]
17 [raster_3d=name] [rules=name] [rgb_column=name] [--help] [--ver‐
18 bose] [--quiet] [--ui]
19
20 Flags:
21 -r
22 Remove existing color table
23
24 -w
25 Only write new color table if it does not already exist
26
27 -l
28 List available rules then exit
29
30 -d
31 List available rules with description then exit
32 If a color rule is given, only this rule is listed
33
34 -n
35 Invert colors
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37 -g
38 Logarithmic scaling
39
40 -a
41 Logarithmic-absolute scaling
42
43 -c
44 Convert color rules from RGB values to color table
45 Option ’rgb_column’ with valid RGB values required
46
47 --help
48 Print usage summary
49
50 --verbose
51 Verbose module output
52
53 --quiet
54 Quiet module output
55
56 --ui
57 Force launching GUI dialog
58
59 Parameters:
60 map=name [required]
61 Name of vector map
62 Or data source for direct OGR access
63
64 layer=string
65 Layer number or name
66 Vector features can have category values in different layers. This
67 number determines which layer to use. When used with direct OGR
68 access this is the layer name.
69 Default: 1
70
71 use=string [required]
72 Source values
73 Options: attr, cat, z
74 Default: cat
75 attr: read values from attribute table (requires <column> option)
76 cat: use category values
77 z: use z coordinate (3D points or centroids only)
78
79 column=name
80 Name of column containing numeric data
81 Required for use=attr
82
83 range=min,max
84 Manually set range (refers to ’column’ option)
85 Ignored when ’rules’ given
86
87 color=style
88 Name of color table
89 Options: aspect, aspectcolr, bcyr, bgyr, blues, byg, byr, celsius,
90 corine, curvature, differences, elevation, etopo2, evi, fahrenheit,
91 gdd, grass, greens, grey, grey.eq, grey.log, grey1.0, grey255, gyr,
92 haxby, inferno, kelvin, magma, ndvi, ndwi, oranges, plasma, popula‐
93 tion, population_dens, precipitation, precipitation_daily, precipi‐
94 tation_monthly, rainbow, ramp, random, reds, roygbiv, rstcurv, ryb,
95 ryg, sepia, slope, soilmoisture, srtm, srtm_plus, terrain, viridis,
96 water, wave
97 aspect: aspect oriented grey colors [range: map values]
98 aspectcolr: aspect oriented rainbow colors [range: 0 to 360]
99 bcyr: blue through cyan through yellow to red [range: map values]
100 bgyr: blue through green through yellow to red [range: map values]
101 blues: white to blue [range: map values]
102 byg: blue through yellow to green [range: map values]
103 byr: blue through yellow to red [range: map values]
104 celsius: blue to red for degree Celsius temperature [range: -80 to
105 80]
106 corine: EU Corine land cover colors [range: 111 to 995]
107 curvature: for terrain curvatures (from v.surf.rst and
108 r.slope.aspect) [range: map values]
109 differences: differences oriented colors [range: map values]
110 elevation: maps relative ranges of raster values to elevation
111 color ramp [range: map values]
112 etopo2: colors for ETOPO2 worldwide bathymetry/topography [range:
113 -11000 to 8850]
114 evi: enhanced vegetative index colors [range: -1 to 1]
115 fahrenheit: blue to red for Fahrenheit temperature [range: -112 to
116 176]
117 gdd: accumulated growing degree days [range: 0 to 6000]
118 grass: GRASS GIS green (perceptually uniform) [range: map values]
119 greens: white to green [range: map values]
120 grey: grey scale [range: map values]
121 grey.eq: histogram-equalized grey scale [range: map values]
122 grey.log: histogram logarithmic transformed grey scale [range: map
123 values]
124 grey1.0: grey scale for raster values between 0.0-1.0 [range: 0 to
125 1]
126 grey255: grey scale for raster values between 0-255 [range: 0 to
127 255]
128 gyr: green through yellow to red [range: map values]
129 haxby: relative colors for bathymetry or topography [range: map
130 values]
131 inferno: perceptually uniform sequential color table inferno
132 [range: map values]
133 kelvin: blue to red for temperature in Kelvin scale [range: 193.15
134 to 353.15]
135 magma: perceptually uniform sequential color table magma [range:
136 map values]
137 ndvi: Normalized Difference Vegetation Index colors [range: -1 to
138 1]
139 ndwi: Normalized Difference Water Index colors [range: -200 to
140 200]
141 oranges: white to orange [range: map values]
142 plasma: perceptually uniform sequential color table plasma [range:
143 map values]
144 population: color table covering human population classification
145 breaks [range: 0 to 2e+09]
146 population_dens: color table covering human population density
147 classification breaks [range: 0 to 1e+09]
148 precipitation: precipitation color table (0..2000mm) [range: 0 to
149 7000]
150 precipitation_daily: precipitation color table (0..1000mm) [range:
151 0 to 10000]
152 precipitation_monthly: precipitation color table (0..1000mm)
153 [range: 0 to 1000]
154 rainbow: rainbow color table [range: map values]
155 ramp: color ramp [range: map values]
156 random: random color table [range: map values]
157 reds: white to red [range: map values]
158 roygbiv: [range: map values]
159 rstcurv: terrain curvature (from r.resamp.rst) [range: map values]
160 ryb: red through yellow to blue [range: map values]
161 ryg: red through yellow to green [range: map values]
162 sepia: yellowish-brown through to white [range: map values]
163 slope: r.slope.aspect-type slope colors for raster values 0-90
164 [range: 0 to 90]
165 soilmoisture: soilmoisture color table (0.0-1.0) [range: 0 to 1]
166 srtm: color palette for Shuttle Radar Topography Mission elevation
167 [range: -11000 to 8850]
168 srtm_plus: color palette for Shuttle Radar Topography Mission ele‐
169 vation (with seafloor colors) [range: -11000 to 8850]
170 terrain: global elevation color table covering -11000 to +8850m
171 [range: -11000 to 8850]
172 viridis: perceptually uniform sequential color table viridis
173 [range: map values]
174 water: water depth [range: map values]
175 wave: color wave [range: map values]
176
177 raster=name
178 Raster map from which to copy color table
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180 raster_3d=name
181 3D raster map from which to copy color table
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183 rules=name
184 Path to rules file
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186 rgb_column=name
187 Name of color column to populate RGB values
188 If not given writes color table
189
191 v.colors allows creating or modifying color table associated with a
192 vector map similarly to r.colors for raster maps.
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194 Color rules are built from features category values (use=cat) or
195 numeric data column (use=attr) defined by column option. For 3D vector
196 maps is allowed to define color rules based on points or centroids
197 z-coordinate (use=z). 3D vector lines are not supported.
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199 The raster option allows user to specify a raster map from which to
200 copy the color table, similarly raster_3d option for 3D raster map.
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202 The rules color table type will cause v.colors to read color table
203 specifications from given file and will build the color table accord‐
204 ingly. See r.colors manual page for details.
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206 If the user specifies the -w flag, the current color table file for the
207 input map will not be overwritten. This means that the color table is
208 created only if the vector map does not already have a color table. If
209 this option is not specified, the color table will be created if one
210 does not exist, or modified if it does.
211
212 Alternatively the color rules can be stored in a string column
213 (rgb_column) by saving the RRR:GGG:BBB values suitable for use with
214 d.vect.
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217 For vector maps with a large number of features it’s more convenient to
218 store color rules in an attribute column (given by rgb_column) rather
219 then in a color table file. Reading color tables with more then 1000
220 items is slow.
221
223 Define color table based on categories
224 Define color table wave based on categories from layer 1
225 v.colors map=soils_general layer=1 color=wave
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227 Define color table based on attribute values
228 Define color table ryg based on values from attribute column AREA.
229 Attribute table is linked to layer 1.
230 v.to.db map=soils_general layer=1 option=area column=AREA
231 v.colors map=soils_general layer=1 color=wave use=attr column=AREA
232
233 Define color table stored as RGB values in attribute table
234 Write color values to the attribute table (column GRASSRGB) instead of
235 creating color table.
236 v.colors map=soils_general layer=1 color=wave use=attr column=AREA rgb_column=GRASSRGB
237 # See some GRASSRGB values:
238 v.db.select map=soils_general where="cat < 4"
239 cat|OBJECTID|AREA|PERIMETER|GSLNC250_|GSLNC250_I|GSL_NAME|GRASSRGB
240 1|1|0|164616.125|2|1|NC113|212:42:127
241 2|2|0|30785.529297|3|2|NC096|212:42:127
242 3|3|0|87572.882812|4|3|NC097|212:42:127
243
244 Convert RGB attribute values into color table
245 Convert existing RGB values to color table rules.
246 v.colors -c map=soils_general rgb_column=GRASSRGB
247 Note that in this case the vector map has a proper color table assigned
248 (check by v.colors.out) together with GRASSRGB attribute column. Also
249 note that color table is preferred over RGB values stored in attribute
250 table.
251
252 Remove existing color table
253 Existing color table can be removed by -r flag.
254 v.colors -r map=soils_general
255 Before removing color table you can store color rules to the file by
256 v.colors.out and later to assign by rules option.
257 v.colors.out map=soils_general rules=soils.colr
258 v.colors map=soils_general rules=soils.colr
259 To drop RGB column use v.db.dropcolumn.
260 v.db.dropcolumn map=soils_general column=GRASSRGB
261
263 d.vect, r.colors, r.colors.out, r3.colors, r3.colors.out, v.colors.out
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265 See also wiki page Color tables (from GRASS User Wiki)
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267 ColorBrewer is an online tool designed to help people select good color
268 schemes for maps and other graphics.
269
271 Martin Landa, OSGeoREL, Czech Technical University in Prague, Czech
272 Republic
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275 Available at: v.colors source code (history)
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277 Main index | Vector index | Topics index | Keywords index | Graphical
278 index | Full index
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280 © 2003-2019 GRASS Development Team, GRASS GIS 7.8.2 Reference Manual
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284GRASS 7.8.2 v.colors(1)