pltree {cluster} | R Documentation |
Plot Clustering Tree of a Hierarchical Clustering
Description
pltree()
Draws a clustering tree (“dendrogram”) on the
current graphics device. We provide the twins
method draws the
tree of a twins
object, i.e., hierarchical clustering,
typically resulting from agnes()
or diana()
.
Usage
pltree(x, ...)
## S3 method for class 'twins'
pltree(x, main = paste("Dendrogram of ", deparse1(x$call)),
labels = NULL, ylab = "Height", ...)
Arguments
x |
in general, an R object for which a |
main |
main title with a sensible default. |
labels |
labels to use; the default is constructed from |
ylab |
label for y-axis. |
... |
graphical parameters (see |
Details
Creates a plot of a clustering tree given a twins
object. The
leaves of the tree are the original observations. In case of an
agglomerative clustering, two branches come together at the distance
between the two clusters being merged. For a divisive clustering, a
branch splits up at the diameter of the cluster being splitted.
Note that currently the method function simply calls
plot(as.hclust(x), ...)
, which dispatches to
plot.hclust(..)
. If more flexible plots are needed,
consider xx <- as.dendrogram(as.hclust(x))
and plotting
xx
, see plot.dendrogram
.
Value
a NULL value is returned.
See Also
agnes
, agnes.object
, diana
,
diana.object
, hclust
, par
,
plot.agnes
, plot.diana
.
Examples
data(votes.repub)
agn <- agnes(votes.repub)
pltree(agn)
dagn <- as.dendrogram(as.hclust(agn))
dagn2 <- as.dendrogram(as.hclust(agn), hang = 0.2)
op <- par(mar = par("mar") + c(0,0,0, 2)) # more space to the right
plot(dagn2, horiz = TRUE)
plot(dagn, horiz = TRUE, center = TRUE,
nodePar = list(lab.cex = 0.6, lab.col = "forest green", pch = NA),
main = deparse(agn$call))
par(op)