creating rainbow gradients
On 17/09/2008 4:58 PM, Gillian Silver wrote:
Hi, how can I create a rainbow gradient in R? For example, let's say I have
a plot of y = x...and I want the plot to go from red -> orange -> yellow ->
green -> blue -> etc.
Right now, I know how to do something like go from red to blue, using the
plotrix library:
library(plotrix)
redToBlue <-
color.scale(x,redrange=c(0,1),greenrange=c(0,1),bluerange=c(0,1),extremes=c("red","blue"))
plot(x, y, col=redToBlue)
But I can't figure out how to make the colors a rainbow. (I don't understand
how the redrange, greenrange, and bluerange parameters in color.scale work.)
Could someone please help?
Others have pointed you to the rainbow() function; you should also look at colorRamp, in case you want to construct your own colour sequence. Duncan Murdoch