R: 4D plot, x, y, z, colours

Question

Could you give me an example on how to use rgl to plot 3 variables at the axes x, y and z and a fourth one with different colours?

thanks

Answer 1

Take a look at example(points3d).

The r3d help page shows you how to draw axes.

x <- c(0, 10, 0, 0)
y <- c(0, 0, 100, 0)
z <- c(0, 0, 0, 1)
i <- c(1,2,1,3,1,4)
labels <- c("Origin", "X", "Y", "Z")
text3d(x,y,z,labels)
segments3d(x[i],y[i],z[i])

Now you add some points

dfr <- data.frame(x = 1:10, y = (1:10)^2, z = runif(10), col = rainbow(10))
with(dfr, points3d(x, y, z, col = col))