Selection Procedure

selection.js

/**
 * Breed a New Generation of Chromosomes
 * */
function breed() {

    var totalFitness = 0;
    var fittest;
    var fit=0;

    /**
     * Calculate fitness of each and every chromosome
     * */
    for(var j = 0 ; j < population.length ; j++){

        var temp = population[j].fitness(75,75,goal);

        if (temp >= fit){

            fit = temp;
            fittest = population[j];// Fittest Chromosome in a Generation

        }

        totalFitness += temp;
    }

    /**
     * Sort the Generation
     * */
    population = population.sort(function(a, b) {
        return b.fitnessValue - a.fitnessValue;
    });

    var newPopulation = [];

    /**
     * Select the Chromosomes with best fitnesses
     * */
    var selectCount = Math.floor(population.length * CROSSOVER_RATE);

    /**
     * Number of Chromosomes that needed to be crossed with the each of the Chosen Chromosome
     * */
    var randCount = Math.ceil(1 / CROSSOVER_RATE);

    /**
     * Select two parents and breed
     * */
    for (var i = 0; i < selectCount; i++) {

        for (var h = 0; h < randCount; h++) {

            var parent = i;

            while (parent == i) {

                parent = (Math.random() * selectCount) >> 0;

            }
            /**
             * Breed
             * */
            var crossed = crossover(population[i], population[parent], CROSSOVER_RATE, GENE_SIZE, CHROME_SIZE);
            newPopulation.push(crossed);
        }
    }
}