Flags:¶

-r

Remove existing color table

-w

Only write new color table if it does not already exist

-l

List available rules then exit

-n

Invert colors

-g

Logarithmic scaling

-a

Logarithmic-absolute scaling

-c

Convert color rules from RGB values to color table
Option ’rgb_column’ with valid RGB values required

--help

Print usage summary

--verbose

Verbose module output

--quiet

Quiet module output

--ui

Force launching GUI dialog

Parameters:¶

map=name [required]

Name of vector map
Or data source for direct OGR access

layer=string

Layer number or name
Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.
Default: 1

use=string [required]

Source values
Options: attr, cat, z
Default: cat
attr: read values from attribute table (requires <column> option)
cat: use category values
z: use z coordinate (3D points or centroids only)

column=name

Name of column containing numeric data
Required for use=attr

range=min,max

Manually set range (refers to ’column’ option)
Ignored when ’rules’ given

color=style

Name of color table
Options: aspect, aspectcolr, bcyr, bgyr, blues, byg, byr, celsius, corine, curvature, differences, elevation, etopo2, evi, fahrenheit, gdd, grass, greens, grey, grey.eq, grey.log, grey1.0, grey255, gyr, haxby, kelvin, ndvi, ndwi, oranges, population, population_dens, precipitation, precipitation_daily, precipitation_monthly, rainbow, ramp, random, reds, roygbiv, rstcurv, ryb, ryg, sepia, slope, soilmoisture, srtm, srtm_plus, terrain, viridis, water, wave
aspect: aspect oriented grey colors
aspectcolr: aspect oriented rainbow colors
bcyr: blue through cyan through yellow to red
bgyr: blue through green through yellow to red
blues: white to blue
byg: blue through yellow to green
byr: blue through yellow to red
celsius: blue to red for degree Celsius temperature
corine: EU Corine land cover colors
curvature: for terrain curvatures (from v.surf.rst and r.slope.aspect)
differences: differences oriented colors
elevation: maps relative ranges of raster values to elevation color ramp
etopo2: colors for ETOPO2 worldwide bathymetry/topography
evi: enhanced vegetative index colors
fahrenheit: blue to red for Fahrenheit temperature
gdd: accumulated growing degree days
grass: GRASS GIS green (perceptually uniform)
greens: white to green
grey: grey scale
grey.eq: histogram-equalized grey scale
grey.log: histogram logarithmic transformed grey scale
grey1.0: grey scale for raster values between 0.0-1.0
grey255: grey scale for raster values between 0-255
gyr: green through yellow to red
haxby: relative colors for bathymetry or topography
kelvin: blue to red for temperature in Kelvin scale
ndvi: Normalized Difference Vegetation Index colors
ndwi: Normalized Difference Water Index colors
oranges: white to orange
population: color table covering human population classification breaks
population_dens: color table covering human population density classification breaks
precipitation: precipitation color table (0..2000mm)
precipitation_daily: precipitation color table (0..1000mm)
precipitation_monthly: precipitation color table (0..1000mm)
rainbow: rainbow color table
ramp: color ramp
random: random color table
reds: white to red
roygbiv: no description
rstcurv: terrain curvature (from r.resamp.rst)
ryb: red through yellow to blue
ryg: red through yellow to green
sepia: yellowish-brown through to white
slope: r.slope.aspect-type slope colors for raster values 0-90
soilmoisture: soilmoisture color table (0.0-1.0)
srtm: color palette for Shuttle Radar Topography Mission elevation
srtm_plus: color palette for Shuttle Radar Topography Mission elevation (with seafloor colors)
terrain: global elevation color table covering -11000 to +8850m
viridis: perceptually uniform sequential color table viridis
water: water depth
wave: color wave

raster=name

Raster map from which to copy color table

raster_3d=name

3D raster map from which to copy color table

rules=name

Path to rules file

rgb_column=name

Name of color column to populate RGB values
If not given writes color table

Define color table based on categories¶

v.colors map=soils_general layer=1 color=wave

Define color table based on attribute values¶

v.to.db map=soils_general layer=1 option=area column=AREA
v.colors map=soils_general layer=1 color=wave use=attr column=AREA

Define color table stored as RGB values in attribute table¶

v.colors map=soils_general layer=1 color=wave use=attr column=AREA rgb_column=GRASSRGB
# See some GRASSRGB values:
v.db.select map=soils_general where="cat < 4"
cat|OBJECTID|AREA|PERIMETER|GSLNC250_|GSLNC250_I|GSL_NAME|GRASSRGB
1|1|0|164616.125|2|1|NC113|212:42:127
2|2|0|30785.529297|3|2|NC096|212:42:127
3|3|0|87572.882812|4|3|NC097|212:42:127

Convert RGB attribute values into color table¶

v.colors -c map=soils_general rgb_column=GRASSRGB

Remove existing color table¶

v.colors -r map=soils_general

v.colors.out map=soils_general rules=soils.colr
v.colors map=soils_general rules=soils.colr

v.db.dropcolumn map=soils_general column=GRASSRGB