GLAD (version 2.36.0)

ColorBar: Calibration bar for color images

Description

This function produces a color image (color bar) which can be used for the legend to another color image obtained from the functions image or arrayPlot.

Usage

ColorBar(x, horizontal=TRUE, col=heat.colors(50), scale=1:length(x), k=10, ...)

Arguments

x

If "numeric", a vector containing the "z" values in the color image, i.e., the values which are represented in the color image. Otherwise, a "character" vector representing colors.

horizontal

If TRUE, the values of x are represented as vertical color strips in the image, else, the values are represented as horizontal color strips.

col

Vector of colors such as that generated by rainbow, heat.colors, topo.colors, terrain.colors, or similar functions. In addition to these color palette functions, a new function myPalette was defined to generate color palettes from user supplied low, middle, and high color values.

scale

A "numeric" vector specifying the "z" values in the color image. This is used when the argument x is a "character" vector representing color information.

k

Object of class "numeric", for the number of labels displayed on the bar.

...

Optional graphical parameters, see par.

See Also

image, arrayPlot myPalette.

Examples

par(mfrow=c(3,1))
Rcol <- myPalette(low="white", high="red", k=10)
Gcol <- myPalette(low="white", high="green", k=50)
RGcol <- myPalette(low="green", high="red", k=100)
ColorBar(Rcol)
ColorBar(Gcol, scale=c(-5,5))
ColorBar(1:50, col=RGcol)

par(mfrow=c(1,3))
x<-seq(-1, 1, by=0.01)
ColorBar(x, col=Gcol, horizontal=FALSE, k=11)
ColorBar(x, col=Gcol, horizontal=FALSE, k=21)
ColorBar(x, col=Gcol, horizontal=FALSE, k=51)