Extract training confusion matrix from a fitted CTA tree

Convenience wrapper: returns the 2x2 integer training confusion matrix for a binary oda_cta_fit result directly, without the intermediate tidy long-format step required by cta_confusion_table and as_confusion_matrix.

Usage

cta_confusion_matrix(tree)

Arguments

tree: A cta_tree from oda_cta_fit.

Value

A 2x2 integer matrix (actual x predicted) or NULL when no tree was found.

Details

Rows are actual class (0/1), columns are predicted class (0/1). Returns NULL invisibly when tree$no_tree is TRUE.

Examples

data(mtcars)
X    <- mtcars[, c("cyl", "disp", "hp", "wt")]
y    <- as.integer(mtcars$am)
tree <- oda_cta_fit(X, y, mindenom = 5L, mc_iter = 500L, mc_seed = 42L)
if (!isTRUE(tree$no_tree)) cta_confusion_matrix(tree)
#>       predicted
#> actual  0  1
#>      0 17  2
#>      1  1 12