evolutionary 0.1.1

A fully extensible Rust framework for using paralyzed genetic algorithms to solve problems.
Documentation 
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use rand::{random, seq::SliceRandom, thread_rng};

use crate::population::Individual;

use super::Selection;

use rayon::prelude::*;

#[derive(Clone)]
pub struct TournamentSelection {
    k: usize,
    kp: f64,
}

impl Default for TournamentSelection {
    fn default() -> Self {
        TournamentSelection { k: 2, kp: 1.0 }
    }
}

impl<T: Individual> Selection<T> for TournamentSelection {
    fn get_mating_pool(&self, initial_population: &Vec<T>) -> Vec<T> {
        initial_population
            .par_iter()
            .map_init(
                || thread_rng(),
                |mut rng, _| {
                    let mut tournament = initial_population
                        .choose_multiple(&mut rng, self.k)
                        .cloned()
                        .collect::<Vec<T>>();

                    tournament
                        .sort_by(|a, b| b.get_fitness().partial_cmp(&a.get_fitness()).unwrap());

                    if random::<f64>() <= self.kp {
                        tournament[0].clone()
                    } else {
                        tournament[1].clone()
                    }
                },
            )
            .collect()
    }
}