Selection.m

%*************************************************************************%
%@BeginVerbatim 
% Function: Selection
% Description: Select two chromosomes for reproduction
% Parameter(s): population, matrix
% Filename: Selection.m
% Version: v00.02
% Author: Group 1
% Yr&Sec: 3-4
% Subject: Computational Intelligence
%@EndVebartim 
%*************************************************************************%

% Last Reviewed by: Periabras, 17 February 2017

%@Code Body***************************************************************%

function [ parent_1, parent_2 ] = Selection( population )
    %@Intialization*******************************************************%
    max_fitness = 100;
    max_cost = 100;
    matingpool = []; %serves as basket from where we are going to choose chromosomes for the reproduction
    %*********************************************************************%
    
    %Loope through the whole population
    for chromosome = 1:length(population)
       %Get the fitness score of the current chromosome
       fitness_score = Fitness(population(chromosome));
       
       %Subtract the fitness score to the max cost to invert the
       %    probability that they will be chosen
       n = floor(max_cost - fitness_score);
       
       %Loop through the total number that they will be added to the
       %    mating pool
       for entry = 1:n
           matingpool = cat(2, matingpool, population(chromosome,:));
       end
    end
    
    %Get a random number from 1 to the length of the mating pool
    chosen_index = randi([1 length(matingpool)], 1);
    %Get the chromosome using the chosen_index
    chosen_chromosome = matingpool(chosen_index);
    %Duplicate the chromosome from population to parent_1
    parent_1 = population(chosen_chromosome,:);
    
    %Get a random number from 1 to the length of the mating pool
    chosen_index = randi([1 length(matingpool)], 1);
    %Get the chromosome using the chosen_index
    chosen_chromosome = matingpool(chosen_index);
    %Duplicate the chromosome from population to parent_2
    parent_2 = population(chosen_chromosome,:);

end

%*************************************************************************%