Trait IndexedMutRandom

pub trait IndexedMutRandom: IndexedRandom + IndexMut<usize>

Extension trait on indexable lists, providing random sampling methods.

This trait is implemented automatically for every type implementing IndexedRandom and [std::ops::IndexMut<usize>].

Provided Methods

fn choose_mut<R>(&mut self, rng: &mut R) -> Option<&mut Self::Output>
where
    R: Rng + ?Sized,

Uniformly sample one element (mut)

Returns a mutable reference to one uniformly-sampled random element of the slice, or None if the slice is empty.

For slices, complexity is O(1).

fn choose_weighted_mut<R, F, B, X>(&mut self, rng: &mut R, weight: F) -> Result<&mut Self::Output, WeightError>
where
    R: Rng + ?Sized,
    F: Fn(&Self::Output) -> B,
    B: SampleBorrow<X>,
    X: SampleUniform + Weight + PartialOrd<X>,

Biased sampling for one element (mut)

Returns a mutable reference to one element of the slice, sampled according to the provided weights.

The specified function weight maps each item x to a relative likelihood weight(x). The probability of each item being selected is therefore weight(x) / s, where s is the sum of all weight(x).

For slices of length n, complexity is O(n). For more information about the underlying algorithm, see the WeightedIndex distribution.

See also choose_weighted.

Implementors