points() colored by value

Hi Chris,

Hi R users,

I want to colored points by their value

for example:

x <- c(1,2,3,4)
y <- c(1,2,3,4)
z <- c(2,3,4,9)

y and x are coordinates

z is the value of the coordinates

points(x,y,col= rainbow(z))

In the general sense:
plot(x, y, col=rainbow(length(unique(z)))[as.factor(z)])

converting z to a factor to use as an index is just a quick way to
convert z to sequential values 1,2,3,4 rather than 2,3,4,9 and to
ensure that multiple and unsorted values use the correct color. If z
contains only sequential values, that bit is unnecessary.

I like RColorBrewer for things like this, rather than rainbow, but it
depends on what you're trying to do.

Sarah

something like that

But haven't found any solution at the moment.

Thanks.

Chris

Sarah Goslee
http://www.functionaldiversity.org