Function gini

pub fn gini<T>(data: &[T]) -> f32
where
    T: Eq + Hash,

Compute the gini impurity of a dataset.

Returns a float, 0 representing a perfectly pure dataset. Normal distribution: ~0.33

By default, any empty dataset will return a gini of 1.0. This may be unexpected behaviour.

use parsnip::gini;
assert_eq!(gini(&vec![0, 0, 0, 1]), 0.375);