[R] 2D plot with colors from 3rd variable?

[Paul Hiemstra]

Hi,

Be sure to take a look at the levelplot() function from the lattice 
package. From the documentation of levelplot:

library(lattice)
x <- seq(pi/4, 5 * pi, length.out = 100)
y <- seq(pi/4, 5 * pi, length.out = 100)
r <- as.vector(sqrt(outer(x^2, y^2, "+")))
grid <- expand.grid(x=x, y=y)
grid$z <- cos(r^2) * exp(-r/(pi^3))
levelplot(z~x*y, grid, cuts = 50, scales=list(log="e"), xlab="",
            ylab="", main="Weird Function", sub="with log scales",
            colorkey = FALSE, region = TRUE)

cheers,
Paul

Josh wrote:
> Hi,
> I have three related variables (vectors) and would like to see their
> distribution on a 2D plot of first two variables, having colors proportional
> to the values from third variable. I could have done so by passing 3rd
> variable to the color palette, but this would disrupt the relationship
> information among them.
> I am sure there has to be some way to do it, but I don't know how. Any help
> in this direction will be appreciated.
>
> thanks
> jo
>
> 	[[alternative HTML version deleted]]
>
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-- 
Drs. Paul Hiemstra
Department of Physical Geography
Faculty of Geosciences
University of Utrecht
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