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Display a color image

Syntax

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

Arguments

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.
z a matrix containing the values to be plotted (NAs are allowed).
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 for plot 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, .

See Also

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

Examples

data(volcano) x <- 10*(1:nrow(volcano)) y <- 10*(1:ncol(volcano)) image(x, y, volcano, col=terrain.colors(100),axes=FALSE) contour(x, y, volcano, levels=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)