commit | 56462585f0da988903f7fbd8a34a0587fd7cc500 | [log] [tgz] |
---|---|---|
author | Wei Li <weiwli@google.com> | Mon Aug 05 23:46:04 2024 +0000 |
committer | Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com> | Mon Aug 05 23:46:04 2024 +0000 |
tree | 4068300cc5a182d630519032dd1f311039fbd964 | |
parent | ee25dafcce1cb86845a89f91663790dda06babef [diff] | |
parent | 3660479ee6049d3a5f78a9495045ef67c33f8147 [diff] |
Cleanup license metadata in external/rust/crates/fastrand. am: 3660479ee6 Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/fastrand/+/3206452 Change-Id: I8a310bb54c02ea22bfaca4e1c4eb764db6fb54f7 Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
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.