partykit (version 1.0-5)

nodeids: Extract Node Identifiers

Description

Extract unique identifiers from inner and terminals nodes of a partynode object.

Usage

nodeids(obj, ...)
"nodeids"(obj, from = NULL, terminal = FALSE, ...)
"nodeids"(obj, from = NULL, terminal = FALSE, ...)

Arguments

obj

an object of class partynode or party.

from

an integer specifying node to start from.

terminal

logical specifying if only node identifiers of terminal nodes are returned.

...

additional arguments.

Value

A vector of node identifiers.

Details

The identifiers of each node are extracted.

Examples

  ## a tree as flat list structure
  nodelist <- list(
      # root node
      list(id = 1L, split = partysplit(varid = 4L, breaks = 1.9),
          kids = 2:3),
      # V4 <= 1.9, terminal node
      list(id = 2L),
      # V4 > 1.9
      list(id = 3L, split = partysplit(varid = 1L, breaks = 1.7),
          kids = c(4L, 7L)),
      # V1 <= 1.7
      list(id = 4L, split = partysplit(varid = 4L, breaks = 4.8),
          kids = 5:6),
      # V4 <= 4.8, terminal node
      list(id = 5L),
      # V4 > 4.8, terminal node
      list(id = 6L),
      # V1 > 1.7, terminal node
      list(id = 7L)
  )

  ## convert to a recursive structure
  node <- as.partynode(nodelist)

  ## set up party object
  data("iris")
  tree <- party(node, data = iris, 
      fitted = data.frame("(fitted)" = 
                          fitted_node(node, data = iris),
                          check.names = FALSE))
  tree
  
  ### ids of all nodes
  nodeids(tree)

  ### ids of all terminal nodes
  nodeids(tree, terminal = TRUE)

  ### ids of terminal nodes in subtree with root [3]
  nodeids(tree, from = 3, terminal = TRUE)