FRand

FRand is a blazingly fast, small, and simple pseudo-random number generator (PRNG) written in Rust. The advantage of using FRand is that it can produce more random numbers per second than other libraries. It also produces high-quality random numbers using a fast non-cryptographic hashing algorithm.

To find the best constants for the algorithm, I used an automated program that tried many random constants per second and measured the bias of the output. The bias was estimated using the avalanche effect, which is a property of good hash functions that ensures that a small change in the input produces a large change in the output. The program selected the constants that minimized the bias and maximized the randomness.

FRand is really simple to use. Here is a simple example of how to use FRand to generate a random float:

use frand::Rand;

let mut rng = Rand::new();
println!("{}", rng.gen::<f32>());

Speeds

u64

rand::ThreadRng	rand::SmallRng	fastrand::Rng	frand::Rand
1.00x	3.74x	5.80x	6.09x

f64

rand::ThreadRng	rand::SmallRng	fastrand::Rng	frand::Rand
1.00x	3.79x	2.34x	5.57x

u128

rand::ThreadRng	rand::SmallRng	fastrand::Rng	frand::Rand
1.00x	2.15x	6.79x	7.24x

If you have suggestions on how to improve this library, you can contribute to this project!