Struct Rng 

pub struct Rng { /* private fields */ }

Implementations

impl Rng

pub fn seed_from(seed: u64) -> Self

pub fn next_u64(&mut self) -> u64

xoshiro256** core step.

pub fn f64(&mut self) -> f64

Uniform in [0, 1) with 53 bits of precision.

pub fn below(&mut self, n: u32) -> u32

Uniform in 0..n. Modulo bias is negligible for the small n used here.

pub fn range_i32(&mut self, lo: i32, hi: i32) -> i32

Uniform integer in lo..=hi.

pub fn normal(&mut self, mu: f64, sigma: f64) -> f64

Gaussian via Box–Muller. Same-build reproducible (the determinism bar the architecture commits to); not bit-portable across compilers.

pub fn poisson(&mut self, lambda: f64) -> u32

Poisson via Knuth’s method — fine for the small λ of goal counts.

pub fn shuffle<T>(&mut self, slice: &mut [T])

Fisher–Yates.

Trait Implementations

impl Clone for Rng

fn clone(&self) -> Rng

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Rng

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.