colorspace (version 0.9)

LAB: Create LAB Colors

Description

This function creates colors of class ``LAB''; a subclass of the virtual ``color'' class.

Usage

LAB(L, A, B, names)

Arguments

L,A,B

these arguments give the L, A and B coordinates of the colors. The values can be provided in separate L, A and B vectors or in a three-column matrix passed as L.

names

a vector of names for the colors (by default the row names of L are used).

Value

• An object of class ``LAB'' which inherits from class ``color.''

Details

The L, A and B values give the coordinates of the colors in the CIE $L^*a^*b^*$ space. This is a transformation of the 1931 CIE XYZ space which attempts to produce perceptually based axes. Luminance takes values between 0 and 100, and the other coordinates take values between -100 and 100. The $a$ and $b$ coordinates measure positions on green/red and blue/yellow axes.

See Also

RGB, HSV, XYZ, LAB, polarLAB, LUV, polarLUV.

Examples

## Show the LAB space
x = RGB(runif(1000), runif(1000), runif(1000))
plot(as(x,"LAB"))