Hierrachical Clustering of Array Columns (Samples) using Pearson Correlation
library (geneplotter)
f.distCol.Pearson <- function (x.mx)
# correlation among columns
        {
        dist.mx <- 1 - cor (x.mx, method = "pearson")
        dist.dmx <- as.dist (dist.mx)
        return (dist.dmx)
        }
x.hclust <- hclust (d = f.distCol.Pearson (x.mx))
plot (  x.hclust,
        main = "",
        xlab = "1 - Pearson Correlation")
