Trait revonet::problem::Problem [−] [src]

pub trait Problem {
    fn compute<T: Individual>(&self, ind: &mut T) -> f32;

    fn is_solution(&self, value: f32) -> bool { ... }

    fn get_random_individual<T: Individual, R: Rng>(
        &self, 
        size: usize, 
        rng: &mut R
    ) -> T { ... }
}

Represents baseline interface for the objective function.

By default solution is represented by a vector of real-numbers.

Example: Custom optimization problem

extern crate revonet;
extern crate rand;

use rand::{Rng, SeedableRng, StdRng};

use revonet::ea::*;
use revonet::problem::*;

// Dummy problem returning random fitness.
pub struct DummyProblem;

impl Problem for DummyProblem {
    // Function to evaluate a specific individual.
    fn compute<T: Individual>(&self, ind: &mut T) -> f32 {
        // use `to_vec` to get real-coded representation of an individual.
        let v = ind.to_vec().unwrap();

        // Perform calculations as per optimization problem being implemened.
        // Here just a random value is returned.
        let mut rng: StdRng = StdRng::from_seed(&[0]);
        rng.gen::<f32>()
    }
}

fn main() {}

Required Methods

Computes fitness value for a given individual.

Arguments:

  • ind - individual to compute a fitness for.

Provided Methods

Returns whether given fitness value is enough to be a solution.

Arguments:

  • value - fitness value to consider.

Generate random individual for the problem. Default implementation creates a real-coded individual with the number of genes equal to size

Arguments:

  • size - number of genes.
  • rng - reference to pre-initialized RNG.

Implementors