| commit | 2640f9606d07aa0003cee91f18d314ae7b2ae788 | [log] [tgz] |
|---|---|---|
| author | Bob Badour <[email protected]> | Thu Feb 23 06:23:44 2023 -0800 |
| committer | Bob Badour <[email protected]> | Thu Feb 23 06:23:44 2023 -0800 |
| tree | 2adc584bbc5832225e27557c8c8582c5968501f7 | |
| parent | 8ea5f7c86d341b6900d55fa658a28453401fbe08 [diff] |
[LSC] Add LOCAL_LICENSE_KINDS to external/rust/crates/fastrand Added SPDX-license-identifier-Apache-2.0 SPDX-license-identifier-MIT to: Android.bp Bug: 68860345 Bug: 151177513 Bug: 151953481 Test: m all Change-Id: I0622587a8d6f82a93dc2fa3ee3ba61b0a8b5b1e3
A simple and fast random number generator.
The implementation uses Wyrand, a simple and fast generator but not cryptographically secure.
Flip a coin:
if fastrand::bool() { println!("heads"); } else { println!("tails"); }
Generate a random i32:
let num = fastrand::i32(..);
Choose a random element in an array:
let v = vec![1, 2, 3, 4, 5]; let i = fastrand::usize(..v.len()); let elem = v[i];
Shuffle an array:
let mut v = vec![1, 2, 3, 4, 5]; fastrand::shuffle(&mut v);
Generate a random Vec or String:
use std::iter::repeat_with; let v: Vec<i32> = repeat_with(|| fastrand::i32(..)).take(10).collect(); let s: String = repeat_with(fastrand::alphanumeric).take(10).collect();
To get reproducible results on every run, initialize the generator with a seed:
// Pick an arbitrary number as seed. fastrand::seed(7); // Now this prints the same number on every run: println!("{}", fastrand::u32(..));
To be more efficient, create a new Rng instance instead of using the thread-local generator:
use std::iter::repeat_with; let rng = fastrand::Rng::new(); let mut bytes: Vec<u8> = repeat_with(|| rng.u8(..)).take(10_000).collect();
Licensed under either of
at your option.
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.