问题
I would like to create a dendrogram in R which has colored branches, like the one shown below.
So far I used following commands to create a standard dendrogram:
d <- dist(as.matrix(data[,29])) # find distance matrix
hc <- hclust(d) # apply hirarchical clustering
plot(hc,labels=data[,1], main="", xlab="") # plot the dendrogram
How should I modify this code to obtain desired result ?
Thanks in advance for your help.
回答1:
You could use the dendextend package, aimed for tasks such as this:
# install the package:
if (!require('dendextend')) install.packages('dendextend'); library('dendextend')
## Example:
dend <- as.dendrogram(hclust(dist(USArrests), "ave"))
d1=color_branches(dend,k=5, col = c(3,1,1,4,1))
plot(d1) # selective coloring of branches :)
d2=color_branches(d1,k=5) # auto-coloring 5 clusters of branches.
plot(d2)
# More examples are in ?color_branches
You can see many examples in the presentations and vignettes of the package, in the "usage" section in the following URL: https://github.com/talgalili/dendextend
回答2:
You should use dendrapply
(help document).
For instance:
# Generate data
set.seed(12345)
desc.1 <- c(rnorm(10, 0, 1), rnorm(20, 10, 4))
desc.2 <- c(rnorm(5, 20, .5), rnorm(5, 5, 1.5), rnorm(20, 10, 2))
desc.3 <- c(rnorm(10, 3, .1), rnorm(15, 6, .2), rnorm(5, 5, .3))
data <- cbind(desc.1, desc.2, desc.3)
# Create dendrogram
d <- dist(data)
hc <- as.dendrogram(hclust(d))
# Function to color branches
colbranches <- function(n, col)
{
a <- attributes(n) # Find the attributes of current node
# Color edges with requested color
attr(n, "edgePar") <- c(a$edgePar, list(col=col, lwd=2))
n # Don't forget to return the node!
}
# Color the first sub-branch of the first branch in red,
# the second sub-branch in orange and the second branch in blue
hc[[1]][[1]] = dendrapply(hc[[1]][[1]], colbranches, "red")
hc[[1]][[2]] = dendrapply(hc[[1]][[2]], colbranches, "orange")
hc[[2]] = dendrapply(hc[[2]], colbranches, "blue")
# Plot
plot(hc)
Which gives:
回答3:
FigTree can make color dendrograms. See for example, this paper.
To get data into FigTree from an R distance matrix dm
,
library(ape)
z <- as.phylo(hclust(as.dist(dm)))
write.nexus(z, file="output.nex")
来源:https://stackoverflow.com/questions/18036094/how-to-create-a-dendrogram-with-colored-branches