Struct RandomKeyChromosome 

pub struct RandomKeyChromosome {
    pub keys: Vec<f64>,
    /* private fields */
}

Random-key chromosome for BRKGA.

Each gene is a floating-point value in [0, 1) that represents a random key. The decoder interprets these keys to construct a solution.

Fields

keys: Vec<f64>

Random keys in [0, 1).

Implementations

impl RandomKeyChromosome

pub fn new(num_keys: usize) -> Self

Creates a new chromosome with the given number of keys.

pub fn random<R: Rng>(num_keys: usize, rng: &mut R) -> Self

Creates a random chromosome.

pub fn len(&self) -> usize

Returns the number of keys.

pub fn is_empty(&self) -> bool

Returns true if empty.

pub fn fitness(&self) -> f64

Returns the fitness value.

pub fn set_fitness(&mut self, fitness: f64)

Sets the fitness value.

pub fn biased_crossover<R: Rng>( &self, other: &Self, elite_bias: f64, rng: &mut R, ) -> Self

Biased crossover with another chromosome.

For each gene, there’s an elite_bias probability of inheriting from self (the elite parent) and 1 - elite_bias from other.

pub fn decode_as_permutation(&self) -> Vec<usize>

Decodes the random keys into a permutation (sorted indices by key value).

This is the most common decoding: sort items by their random keys to get a placement order.

pub fn decode_as_discrete(&self, key_idx: usize, num_options: usize) -> usize

Decodes a subset of keys as discrete values in a range.

For example, to decode orientation (0-5), use: decode_as_discrete(key_idx, 6) which maps [0, 1) to {0, 1, 2, 3, 4, 5}.

pub fn discrete_key(choice: usize, num_options: usize) -> f64

The key Self::decode_as_discrete reads as choice of num_options – how a known solution is written into a chromosome.

decode_as_discrete maps the interval [choice / num_options, (choice + 1) / num_options) to choice; this is its midpoint, the furthest a key can be from either edge, so a crossover that nudges it still decodes as the same choice.

pub fn permutation_keys(order: &[usize], num_items: usize) -> Vec<f64>

The keys Self::decode_as_permutation reads back as order – order[rank] is the item placed rank-th. Items order leaves out keep key 0.

Trait Implementations

impl Clone for RandomKeyChromosome

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RandomKeyChromosome

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

Formats the value using the given formatter.