tag | 7e9998922f76e5068249752e3ae50a59f15459c3 | |
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tagger | Xin Li <delphij@google.com> | Wed Apr 24 19:37:48 2024 -0700 |
object | 4873a67ba89ba22e87271e5125d6a108ae8137f1 |
aml_hef_341613000 (11465779,com.google.android.healthfitness)
commit | 4873a67ba89ba22e87271e5125d6a108ae8137f1 | [log] [tgz] |
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author | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Sat Jul 08 04:32:03 2023 +0000 |
committer | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Sat Jul 08 04:32:03 2023 +0000 |
tree | db504e270310dcd06e1372842ea617bccc9a5852 | |
parent | 9f13c44bb53a7a2e4d6d0fcf1b67ec8eb0959d71 [diff] | |
parent | ca4cfed67823b583c62aca9f2a20d3cd699afe11 [diff] |
Snap for 10460766 from ca4cfed67823b583c62aca9f2a20d3cd699afe11 to mainline-healthfitness-release Change-Id: Ic15e37c22b4c3656df056d1ecf7fd256f72f228b
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.