Hi, I was trying to generate a heatmap with three colors (I have three values i.e, -1,0,1). I was using the following code (suggested earlier): ----------------------------------------------- r1 <- matrix(0:1,11,5) r2 <- matrix(-1:0,13,5) matr <- rbind(r1,r2) rownames(matr) <- LETTERS[1:nrow(matr)] colnames(matr) <- 1:5 heatmap(matr,col=c('green','black','red')) --------------------------------------------- What I want is for the -1 values to be green cells, 0 values to be black cells & 1 values to be red cells. However, I only seem to get red and green colors in the cell. What do I need to do to get this right? thanks! [[alternative HTML version deleted]]

heatmap(matr,col=c('green','black','red'), scale='none') On 19 Sep 2008, at 13:24, Tim Smith wrote: > r1 <- matrix(0:1,11,5) > r2 <- matrix(-1:0,13,5) > matr <- rbind(r1,r2) > rownames(matr) <- LETTERS[1:nrow(matr)] > colnames(matr) <- 1:5 > heatmap(matr,col=c('green','black','red')) Stephen Henderson Viral Oncology (5th Floor) UCL Cancer Institute Paul O'Gorman Building Huntley Street London, WC1E 6BT s.henderson at ucl.ac.uk +44 (0) 207 679 6827