This package enables you to create dendrograms and tree plots using ggplot
.
The ggplot2
philosophy is to clearly separate data from the presentation. Unfortunately the plot method for dendrograms (plot.dendrogram
) plots directly to a plot device without exposing the data. The ggdendro package resolves this by making available functions that extract the dendrogram plot data. This data can be used with ggplot
.
The function dendro_data
extracts data from different objects that contain dendrogram information. It is a generic function with methods for:
hclust: dendro_data.hclust
dendrogram: dendro_data.dendrogram
regression trees: dendro_data.tree
partition trees: dendro_data.rpart
agnes and diana: dendro_data.twins
These methods create an object of class dendro
, consisting of a list of data frames. To extract the relevant data frames from the list, you can use the accessor functions:
segment
: the line segment data
label
: the text for each end segment
leaf_label
: the leaf labels of a tree diagram
To plot a dendrogram, either construct a plot with ggplot
or use the function ggdendrogram
.