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rgb {base}R Documentation

RGB Color Specification

Description

This function creates “colors” corresponding to the given intensities (between 0 and max) of the red, green and blue primaries. The names argument may be used to provide names for the colors.

The values returned by rgb can be used with a col= specification in graphics functions or in par.

Usage

rgb(red, green, blue, names=NULL, maxColorValue = 1)

Arguments

red, blue, green

vectors of same length with values in [0, M] where M is maxColorValue. When this is 255, the red, blue and green values are coerced to integers in 0:255 and the result is computed most efficiently.

names

character. The names for the resulting vector.

maxColorValue

number giving the maximum of the color values range, see above.

See Also

col2rgb the “inverse” for translating R colors to RGB vectors.
rainbow, hsv, gray.

Examples

rgb(0,1,0)
(u01 <- seq(0,1, length=11))
stopifnot(rgb(u01,u01,u01) == gray(u01))
reds <- rgb((0:15)/15, g=0,b=0, names=paste("red",0:15,sep="."))
reds

rgb(0, 0:12, 0, max = 255)# integer input
[Package base version 1.7.1 ]