pals (version 1.9)

pal.maxdist: Measure the maximum distance between two palettes

Description

Measure the maximum distance between two palettes

Usage

pal.maxdist(pal1, pal2, n = 255)

Value

Numeric value of the maximum distance.

Arguments

pal1

A color palette (function or vector)

pal2

A color palette (function or vector)

n

Number of colors to use, default 255

Author

Kevin Wright

Details

The distance between two palettes (of equal length) is calculated pointwise using the Lab color space. A 'just noticeable difference' between colors is roughly 2.3.

References

https://en.wikipedia.org/wiki/Color_difference

Examples

pa0 <- c("#ff0000","#00ff00","#0000ff")
pa1 <- c("#fa0000","#00fa00","#0000fa") # 2.4
pa2 <- c("#f40000","#00f400","#0000f4") # 5.2
pal.maxdist(pa0,pa1) # 2.36
pal.maxdist(pa0,pa2) # 5.20
pal.bands(pa1,pa0,pa2, labels=c("2.36","0","5.20"))
title("Maximum Lab distance from middle palette")

# distance between colormap functions
pal.maxdist(coolwarm,warmcool)