identify.dendrogram: Identify Clusters in a Dendrogram (not hclust)
Description
Just like identify.hclust:
reads the position of the graphics pointer when the (first)
mouse button is pressed. It then cuts the tree at the vertical
position of the pointer and highlights the cluster containing
the horizontal position of the pointer. Optionally a function is applied
to the index of data points contained in the cluster.
Usage
## S3 method for class 'dendrogram':
identify(x, FUN = NULL, N = 20, MAXCLUSTER,
DEV.FUN = NULL, horiz = FALSE, ...)
(optional) function to be applied to the index numbers of the
data points in a cluster (see 'Details' below).
N
the maximum number of clusters to be identified.
MAXCLUSTER
the maximum number of clusters that can be produced by
a cut (limits the effective vertical range of the pointer).
DEV.FUN
(optional) integer scalar. If specified, the corresponding
graphics device is made active before FUN is applied.
horiz
logical (FALSE), indicating if the rectangles
should be drawn horizontally or not (for when using
plot(dend, horiz = TRUE) ) .
...
further arguments to FUN.
Value
(Invisibly) returns a list where each element contains a vector
of data points contained in the respective cluster.
source
This function is based on identify.hclust, with slight modifications
to have it work with a dendrogram, as well as adding "horiz"
Details
By default clusters can be identified using the mouse and an invisible
list of indices of the respective data points is returned.
If FUN is not NULL, then the index vector of data points is passed to this
function as first argument, see the examples below. The active
graphics device for FUN can be specified using DEV.FUN.
The identification process is terminated by pressing any mouse button other
than the first, see also identify.