cutree {stats} | R Documentation |
Cuts a tree, e.g., as resulting from hclust
, into several
groups either by specifying the desired number(s) of groups or the cut
height(s).
cutree(tree, k = NULL, h = NULL)
tree |
a tree as produced by |
k |
an integer scalar or vector with the desired number of groups |
h |
numeric scalar or vector with heights where the tree should be cut. |
At least one of k
or h
must be specified, k
overrides h
if both are given.
Cutting trees at a given height is only possible for ultrametric trees (with monotone clustering heights).
cutree
returns a vector with group memberships if k
or
h
are scalar, otherwise a matrix with group memberships is returned
where each column corresponds to the elements of k
or h
,
respectively (which are also used as column names).
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
hclust
, dendrogram
for cutting trees themselves.
hc <- hclust(dist(USArrests))
cutree(hc, k = 1:5) #k = 1 is trivial
cutree(hc, h = 250)
## Compare the 2 and 4 grouping:
g24 <- cutree(hc, k = c(2,4))
table(grp2 = g24[,"2"], grp4 = g24[,"4"])