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Build a dimoose key from a classification tree

Source: R/keys.R
keyFromRpart.Rd

Converts an rpart::rpart() classification tree into a dichotomous key: every split becomes a couplet with two leads, and every leaf a result. Taxa that the tree cannot separate share a leaf and are listed together ("A / B").

Usage

keyFromRpart(
  fit,
  desc = "Key generated from a classification tree",
  meta = NULL
)

Arguments

fit

An rpart object with method = "class", e.g. from generateTree().

desc

Title of the key.

meta

Key/value metadata data frame.

Value

A dimoose object.

See also

vibrioKey()

Examples

d <- data.frame(
  taxon = factor(c("A", "B", "C")),
  wings = factor(c("+", "-", "-")),
  spots = factor(c("-", "+", "-"))
)
fit <- generateTree(d, "taxon",
  params = list(control = rpart::rpart.control(minsplit = 2, minbucket = 1, cp = 0)))
keyFromRpart(fit, "Three taxa")$leads
#>   Statement Choice Character Next Taxon
#> 1         1      a  wings: +    -     A
#> 2         1      b  wings: -    2      
#> 3         2      a  spots: +    -     B
#> 4         2      b  spots: -    -     C