[−][src]Function rand::seq::sample_indices_cache
fn sample_indices_cache<R: ?Sized>(
rng: &mut R,
length: usize,
amount: usize
) -> Vec<usize> where
R: Rng,
This method performs a partial fisher-yates on a range of indices using a
HashMap
as a cache to record potential collisions.
The cache avoids allocating the entire length
of values. This is especially useful when
amount <<< length
, i.e. select 3 non-repeating from 1_000_000