#[macro_use(bitset)]
extern crate compacts;

use compacts::bits::{PopCount, Set};

struct Jaccard;
struct Cosine;

impl Jaccard {
    fn similarity(x: &Set, y: &Set) -> f64 {
        let p = x.count1();
        let q = y.count1();
        let both = x.and(y).collect::<Set>().count1();
        both as f64 / (p + q - both) as f64
    }
}

impl Cosine {
    fn similarity(x: &Set, y: &Set) -> f64 {
        let p = x.count1();
        let q = y.count1();
        let both = x.and(y).collect::<Set>().count1();
        both as f64 / ((p * q) as f64).sqrt()
    }
}

#[test]
fn jaccard_similarity() {
    let b1 = bitset!(0, 2, 3, 4);
    let b2 = bitset!(0, 1, 3, 4, 6);
    eprintln!("jaccard {}", Jaccard::similarity(&b1, &b2));
}

#[test]
fn cosine_similarity() {
    let b1 = bitset!(0, 2, 3, 4);
    let b2 = bitset!(0, 1, 3, 4, 6);
    eprintln!("cosine  {}", Cosine::similarity(&b1, &b2));
}