out

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

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

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.

Benchmarks

n = 100, len = 1_000_000:

``` openSUSE Tumbleweed, i7-5820K @ 3.30GHz, and 16GiB RAM:

test binaryheap ... bench: 6,599,355 ns/iter (+/- 84,674) test max ... bench: 669,726 ns/iter (+/- 13,595) test maxunstable ... 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)

openSUSE Leap 15.0, i7-7700 @ 3.60GHz, and 32GiB RAM:

test binaryheap ... bench: 5,521,422 ns/iter (+/- 124,780) test max ... bench: 653,428 ns/iter (+/- 13,913) test maxunstable ... bench: 524,200 ns/iter (+/- 61,033) test sort ... bench: 41,428,917 ns/iter (+/- 486,681) test sort_unstable ... bench: 26,124,912 ns/iter (+/- 439,856)

Windows 10 Pro, i7-5820K @ 3.30GHz, and 16GiB RAM:

test binaryheap ... bench: 8,550,850 ns/iter (+/- 1,118,958) test max ... bench: 2,282,062 ns/iter (+/- 564,063) test maxunstable ... bench: 2,179,817 ns/iter (+/- 741,751) test sort ... bench: 67,915,490 ns/iter (+/- 5,252,960) test sort_unstable ... bench: 34,022,120 ns/iter (+/- 3,745,490) ```

License

Licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.