dendro_data.tree: Extract data from regression tree object for plotting using...

In andrie/ggdendro: Create Dendrograms and Tree Diagrams Using 'ggplot2'

Extract data from regression tree object for plotting using ggplot.

Description

Extracts data to plot line segments and labels from a tree::tree() object. This data can then be manipulated or plotted, e.g. using ggplot2::ggplot().

Usage

## S3 method for class 'tree'
dendro_data(model, type = c("proportional", "uniform"), ...)

Arguments

model	object of class "tree", e.g. the output of tree()
type	Either proportional or uniform. If this partially matches "uniform", the branches are of uniform length. Otherwise they are proportional to the decrease in impurity.
...	ignored

Value

A list of three data frames:

segments	a data frame containing the line segment data
labels	a data frame containing the label text data
leaf_labels	a data frame containing the leaf label text data

Author(s)

Andrie de Vries, using code modified from original by Brian Ripley

See Also

ggdendrogram()

Other dendro_data methods: dendro_data(), dendro_data.rpart(), dendrogram_data(), rpart_labels()

Other tree functions: get_data_tree_leaf_labels(), tree_labels(), tree_segments()

Examples

### Demonstrate tree

if (require(tree)) {
  require(ggplot2)
  require(MASS)
  data(cpus, package = "MASS")
  cpus.ltr <- tree(log10(perf) ~ syct + mmin + mmax + cach + chmin + chmax, 
                   data = cpus)
  tree_data <- dendro_data(cpus.ltr)
  ggplot(segment(tree_data)) +
    geom_segment(aes(x = x, y = y, xend = xend, yend = yend, linewidth = n),
      colour = "lightblue"
    ) +
    scale_size("n") +
    geom_text(
      data = label(tree_data),
      aes(x = x, y = y, label = label), vjust = -0.5, size = 4
    ) +
    geom_text(
      data = leaf_label(tree_data),
      aes(x = x, y = y, label = label), vjust = 0.5, size = 3
    ) +
    theme_dendro()
}

andrie/ggdendro documentation built on April 1, 2024, 6:44 p.m.