Crate out

Provides functionality to get the n largest items from a &mut [T].

let mut v = [-5, 4, 1, -3, 2];
let max = out::max(&mut v, 3);
assert_eq!(max, [1, 2, 4]);

It's worth noting that the largest item will be the last item in the slice that is returned. This library can provide significant performance increase compared to sorting or converting to a heap when n is relatively small compared to the length of the slice. In addition, the unstable methods can be used without the standard library by disabling the default features.

n = 100, len = 1_000_000:

test binary_heap   ... bench:   6,599,355 ns/iter (+/- 84,674)
test max           ... bench:     669,726 ns/iter (+/- 13,595)
test max_unstable  ... bench:     635,435 ns/iter (+/- 9,683)
test sort          ... bench:  62,585,547 ns/iter (+/- 1,361,258)
test sort_unstable ... bench:  34,595,265 ns/iter (+/- 739,255)

n = 1000, len = 10_000_000:

test binary_heap   ... bench:  78,343,761 ns/iter (+/- 2,579,283)
test max           ... bench:  14,970,673 ns/iter (+/- 580,660)
test max_unstable  ... bench:  14,870,344 ns/iter (+/- 573,286)
test sort          ... bench: 716,240,206 ns/iter (+/- 23,188,586)
test sort_unstable ... bench: 385,681,859 ns/iter (+/- 19,847,519)

Functions

max	Get the n largest items.
max_by	Get the n largest items with a comparator function.
max_by_key	Get the n largest items with a key extraction function.
max_unstable	Get the n largest items.
max_unstable_by	Get the n largest items with a comparator function.
max_unstable_by_key	Get the n largest items with a key extraction function.