A simple and fast random number generator.
The implementation uses Wyrand, a simple and fast generator but not cryptographically secure.
Flip a coin:
rust
if fastrand::bool() {
println!("heads");
} else {
println!("tails");
}
Generate a random i32:
rust
let num = fastrand::i32(..);
Choose a random element in an array:
rust
let v = vec![1, 2, 3, 4, 5];
let i = fastrand::usize(..v.len());
let elem = v[i];
Sample values from an array with O(n) complexity (n is the length of array):
rust
fastrand::choose_multiple(vec![1, 4, 5].iter(), 2);
fastrand::choose_multiple(0..20, 12);
Shuffle an array:
rust
let mut v = vec![1, 2, 3, 4, 5];
fastrand::shuffle(&mut v);
Generate a random Vec or String:
```rust use std::iter::repeat_with;
let v: Vec
To get reproducible results on every run, initialize the generator with a seed:
```rust // 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:
```rust use std::iter::repeat_with;
let rng = fastrand::Rng::new();
let mut bytes: Vec
std (enabled by default): Enables the std library. This is required for the global
generator and global entropy. Without this feature, [Rng] can only be instantiated using
the with_seed method.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.