Ordering or Labels of the Leaves in a Dendrogram

Description

Theses functions return the order (index) or the "label" attribute for the leaves in a dendrogram. These indices can then be used to access the appropriate components of any additional data.

Usage

order.dendrogram(x)

## S3 method for class 'dendrogram':
labels(object, ...)

Arguments

Details

The indices or labels for the leaves in left to right order are retrieved.

Value

A vector with length equal to the number of leaves in the dendrogram is returned. From r <- order.dendrogram(), each element is the index into the original data (from which the dendrogram was computed).

Author(s)

R. Gentleman (order.dendrogam and Martin Maechler (labels.dendrogram).

See Also

reorder, dendrogram.

Examples

set.seed(123)
x <- rnorm(10)
hc <- hclust(dist(x))
hc$order
dd <- as.dendrogram(hc)
order.dendrogram(dd) ## the same :
stopifnot(hc$order == order.dendrogram(dd))

d2 <- as.dendrogram(hclust(dist(USArrests)))
labels(d2) ## in this case the same as
stopifnot(labels(d2) == rownames(USArrests)[order.dendrogram(d2)])