[−][src]Crate out
Provides functionality to get the n
largest items from slices and iterators.
let mut v = [-5, 4, 1, -3, 2]; let max = out::slice::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 small compared to the length of the slice or iterator.
Benchmarks
n = 100
, len = 1_000_000
:
openSUSE Tumbleweed, i7-5820K @ 3.30GHz, and 16GiB RAM:
test iter::max ... bench: 918,253 ns/iter (+/- 99,863)
test iter::max_unstable ... bench: 916,908 ns/iter (+/- 58,050)
test slice::max ... bench: 698,643 ns/iter (+/- 46,373)
test slice::max_by_cached_key ... bench: 1,516,099 ns/iter (+/- 37,853)
test slice::max_unstable ... bench: 655,286 ns/iter (+/- 25,017)
test std::binary_heap ... bench: 6,592,801 ns/iter (+/- 780,590)
test std::sort ... bench: 63,192,028 ns/iter (+/- 2,338,506)
test std::sort_by_cached_key ... bench: 66,058,834 ns/iter (+/- 5,447,387)
test std::sort_unstable ... bench: 30,953,024 ns/iter (+/- 1,141,696)
Windows 10 Pro (msvc), i7-5820K @ 3.30GHz, and 16GiB RAM:
test iter::max ... bench: 2,650,615 ns/iter (+/- 1,427,458)
test iter::max_unstable ... bench: 2,604,860 ns/iter (+/- 1,001,639)
test slice::max ... bench: 2,353,487 ns/iter (+/- 1,140,791)
test slice::max_by_cached_key ... bench: 3,317,930 ns/iter (+/- 1,115,283)
test slice::max_unstable ... bench: 2,221,975 ns/iter (+/- 1,232,170)
test std::binary_heap ... bench: 8,666,095 ns/iter (+/- 3,790,987)
test std::sort ... bench: 73,953,630 ns/iter (+/- 23,036,689)
test std::sort_by_cached_key ... bench: 79,681,540 ns/iter (+/- 24,554,555)
test std::sort_unstable ... bench: 35,327,180 ns/iter (+/- 8,306,700)
Modules
iter | Functions for use with iterators. |
slice | Functions for use with slices. |