order.dendrogram            package:stats            R Documentation

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:

x, object: a dendrogram (see 'as.dendrogram').

     ...: additional 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.dendrogram' 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)])

