Function comb

crates/openquant/src/ef3m.rs:28–40

(n: usize, k: usize)

    pub error: f64,
}

fn comb(n: usize, k: usize) -> f64 {
    if k > n {
        return 0.0;
    }
    let k_eff = k.min(n - k);
    let mut num = 1.0;
    let mut den = 1.0;
    for i in 0..k_eff {
        num *= (n - i) as f64;
        den *= (i + 1) as f64;
    }
    num / den
}

fn round_to_5(x: f64) -> f64 {