Crate red_primality

Source
Expand description

red_primality provides zero-setup primality testing and factoring for all u64

§Example

use red_primality::{ is_u64_prime, factor, Prime, euler_totient, mobius };

fn main() {
    // Primality testing
    assert!(is_u64_prime(5));
    assert!(!is_u64_prime(6));

    // Factoring a near-worst-case semiprime
    let facs: Vec<(Prime, u64)> = factor(18302912619494838287).iter().collect();
    let p1 = Prime::new(4278190337).unwrap();
    let p2 = Prime::new(4278190351).unwrap();
    assert_eq!(facs, vec![(p1, 1), (p2, 1)]);

    // Euler's totient function
    assert_eq!(euler_totient(180), (1*2) * (2*3) * (4));

    // mobius(x,y) is the Möbius function of the ratio x/y
    assert_eq!(mobius(90, 2), 0);  // 90/2 = 45, contiains 3^2
    assert_eq!(mobius(90, 3), -1);  // 90/3 = 30 = 2*3*5, so -1
    assert_eq!(mobius(90, 6), 1);  // 90/6 = 15 = 3*5, so +1
}

Structs§

  • CertIter
    Produces a sequence of certified primes.
  • Prime
    Wrapper type certifying that a u64 is prime.
  • PrimeFactorization
    Represents a collection of powers of prime factors.
  • PrimeIter
    PrimeIter returns a sequence of primes in ascending order.

Constants§

  • MAX_U64_PRIME
    This is the largest prime integer that fits in a u64.

Functions§