| % File src/library/stats/man/cutree.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2007 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{cutree} |
| \alias{cutree} |
| \title{Cut a Tree into Groups of Data} |
| \description{ |
| Cuts a tree, e.g., as resulting from \code{\link{hclust}}, into several |
| groups either by specifying the desired number(s) of groups or the cut |
| height(s). |
| } |
| \usage{ |
| cutree(tree, k = NULL, h = NULL) |
| } |
| \arguments{ |
| \item{tree}{a tree as produced by \code{\link{hclust}}. \code{cutree()} |
| only expects a list with components \code{merge}, \code{height}, and |
| \code{labels}, of appropriate content each.} |
| \item{k}{an integer scalar or vector with the desired number of groups} |
| \item{h}{numeric scalar or vector with heights where the tree should |
| be cut.} |
| At least one of \code{k} or \code{h} must be specified, \code{k} |
| overrides \code{h} if both are given. |
| } |
| \references{ |
| Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) |
| \emph{The New S Language}. |
| Wadsworth & Brooks/Cole. |
| } |
| \value{ |
| \code{cutree} returns a vector with group memberships if \code{k} or |
| \code{h} are scalar, otherwise a matrix with group memberships is returned |
| where each column corresponds to the elements of \code{k} or \code{h}, |
| respectively (which are also used as column names). |
| } |
| \details{ |
| Cutting trees at a given height is only possible for ultrametric trees |
| (with monotone clustering heights). |
| } |
| \seealso{ |
| \code{\link{hclust}}, \code{\link{dendrogram}} for cutting trees themselves. |
| } |
| \examples{ |
| 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"]) |
| } |
| \keyword{multivariate} |
| \keyword{cluster} |