Subtree

Extracts a subtree with a user-specified number of leaves from an rpart object.

subtree(tree, leaves = NULL, cv = FALSE)

Arguments

tree

An rpart object.

leaves

Number of leaves of the desired subtree.

cv

If TRUE, leaves is ignored and a cross-validation criterion is used to select a partition.

Value

The subtree, as an rpart object.

See also

get_leaves node_membership leaf_membership

Author

Riccardo Di Francesco

Examples

## Generate data.
set.seed(1986)

n <- 3000
k <- 3

X <- matrix(rnorm(n * k), ncol = k)
colnames(X) <- paste0("x", seq_len(k))

Y <- exp(X[, 1]) + 2 * X[, 2] * X[, 2] > 0 + rnorm(n)

## Construct tree.
library(rpart)
tree <- rpart(Y ~ ., data = data.frame(Y, X), cp = 0)

## Extract subtree.
sub_tree <- subtree(tree, leaves = 4)
sub_tree_cv <- subtree(tree, cv = TRUE)