[R] Colouring hclust() trees

[Martin Keller-Ressel]

How about this:

"hc" is your hclust object,"colv" the color vector ordered like the 
original data
and "height" the height of the color bar as fraction of dendrogram height.

colorplot.hclust <- function(hc,colv,height=.05) {
     plot(hc,lab=FALSE,hang=0)
     stopifnot(length(hc$order) == length(colv))
     xy.mat <- list(x=1:length(colv),y=c(-max(hc$height)*height,0))
     image(xy.mat,z=matrix(colv[hc$order],ncol=1),add=TRUE)
}

## Example:

data(iris)
hc1 <- hclust(dist(scale(iris[,1:4])),method="ward")
colorplot.hclust(hc1,as.numeric(iris[,5]))


hth,

Martin Keller-Ressel



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