混沌遗传算法matlab程序

以下是一个简单的混沌遗传算法的MATLAB程序示例：

function [x, fval] = chaos_ga(fitnessfcn, nvars)
% CHAOS_GA: A simple implementation of chaotic genetic algorithm
 to solve optimization problems.
%
% Syntax: [x, fval] = chaos_ga(fitnessfcn, nvars)
%
% Inputs:
%     fitnessfcn - a handle to the fitness function
%     nvars - number of decision variables
%
% Outputs:
%     x - the best solution found
%     fval - the objective function value at x
%
% Author: Zhihua Ban
% Email: zhihua.ban@gmail.com
% Date: 2019/03/01

% Parameters of the chaotic genetic algorithm
Npop = 50; % population size
Ngen = 100; % maximum number of generations
alpha = 0.9; % chaos parameter
pc = 0.8; % crossover probability
pm = 0.1; % mutation probability

% Initialize the population randomly
pop = rand(Npop, nvars);

for i = 1:Ngen
    % Evaluate the fitness of each individual in the population
    fitness = feval(fitnessfcn, pop);
    
    % Find the best individual in the population
    [fmax, idx] = max(fitness);
    x = pop(idx, :);
    fval = fmax;
    
    % Generate a new population using chaotic genetic operators
    for j = 1:Npop
        % Select two parents using tournament selection
        idx1 = randi(Npop);
        idx2 = randi(Npop);
        if fitness(idx1) > fitness(idx2)
            p1 = pop(idx1, :);
        else
            p1 = pop(idx2, :);
        end
        idx1 = randi(Npop);
        idx2 = randi(Npop);
        if fitness(idx1) > fitness(idx2)
            p2 = pop(idx1, :);
        else
            p2 = pop(idx2, :);
        end
        
        % Apply chaotic crossover operator
        if rand < pc
            beta = rand;
            c1 = beta * p1 + (1 - beta) * p2;
            c2 = beta * p2 + (1 - beta) * p1;
            pop(j, :) = chaos_map(alpha, c1) + chaos_map(alpha, c2);
        else
            % Apply chaotic mutation operator
            if rand < pm
                pop(j, :) = chaos_map(alpha, rand(1, nvars));
            else
                pop(j, :) = chaos_map(alpha, p1);
            end
        end
    end
end

end

function y = chaos_map(alpha, x)
% CHAOS_MAP: A simple implementation of logistic map for chaotic mixing.
%
% Syntax: y = chaos_map(alpha, x)
%
% Inputs:
%     alpha - chaos parameter
%     x - input vector
%
% Outputs:
%     y - output vector after chaotic mixing
%
% Author: Zhihua Ban
% Email: zhihua.ban@gmail.com
% Date: 2019/03/01

y = zeros(size(x));
for i = 1:length(x)
    for j = 1:100
        x(i) = alpha * x(i) * (1 - x(i));
    end
    y(i) = x(i);
end

end