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Display a color image

Syntax

image(z, x, y, zlim, col=heat.colors(12), ...)

heat.colors(n)
topo.colors(n) 
terrain.colors(n)

Arguments

z a matrix containing the values to be plotted (NAs are allowed).
x,y locations of grid lines at which the values in z are measured. These must be in ascending order. By default, equally spaced values from 0 to 1 are used.
zlim the minimum and maximum z values for which colors will be plotted. Each of the given colors will be used to color an equispaced interval of this range.
col A list of colors such as that generated by rainbow, heat.colors, topo.colors, terrain.colors or similar functions.
... graphical parameters may also be passed as arguments to this function.

Description

Creates a grid of colored or gray-scale rectangles with colors corresponding to the values in z. This can be used to display three-dimensional or spatial data. The functions heat.colors, terrain.colors and topo.colors create heat-spectrum (red to white) and topographical color schemes suitable for displaying ordered data, with n giving the number of colors desired.

Note

This function is based on an interpreted function written by Thomas Lumley (thomas@biostat.washington.edu).

See Also

heat.colors, topo.colors, terrain.colors, rainbow, hsv, par.

Examples

data(volcano) x <- 10*(1:nrow(volcano)) y <- 10*(1:ncol(volcano)) image(volcano, x, y, col=terrain.colors(100),axes=FALSE) contour(volcano, x, y, zc=seq(90, 200, by=5), add=TRUE, col="peru") axis(1, at=seq(100, 800, by=100)) axis(2, at=seq(100, 600, by=100)) box() title(main="Maunga Whau Volcano", font.main=4)