Particle swarm optimization (PSO)_Algorithm_2D

Particle swarm optimization (PSO)_Algorithm

%%http://en.wikipedia.org/wiki/Particle_swarm_optimization

function [pso F] = pso_2D()
%   FUNCTION PSO  --------USE Particle Swarm Optimization Algorithm
%global present;
% close all;
pop_size = 10;          %   pop_size 
part_size = 2;          %   part_siz=n-D
gbest = zeros(1,part_size+1);           
max_gen = 80;          
region=zeros(part_size,2); 
region=[-3,3;-3,3];          


rand('state',sum(100*clock)); 
arr_present = ini_pos(pop_size,part_size);  

v=ini_v(pop_size,part_size);          


pbest = zeros(pop_size,part_size+1);
w_max = 0.9;                            ֵ
w_min = 0.4;
v_max = 2;          
c1 = 2;           
c2 = 2;                 
best_record = zeros(1,max_gen);     


arr_present(:,end)=ini_fit(arr_present,pop_size,part_size);

% for k=1:pop_size
%     present(k,end) = fitness(present(k,1:part_size));  
% end

pbest = arr_present;                                        ֵ
[best_value best_index] = min(arr_present(:,end));         ֵ
gbest = arr_present(best_index,:);
%v = zeros(pop_size,1);         


%  
% global m;
% m = moviein(1000);      
x=[-3:0.01:3];
y=[-3:0.01:3];
z=@(x,y) 3*(1-x).^2.*exp(-(x.^2) - (y+1).^2)- 10*(x/5 - x.^3 - y.^5).*exp(-x.^2-y.^2)- 1/3*exp(-(x+1).^2 - y.^2);
for i=1:max_gen
    grid on;
    %     plot3(x,y,z);
    %     subplot(121),ezmesh(z),hold on,grid on,plot3(arr_present(:,1),arr_present(:,2),arr_present(:,3),'*'),hold off;
    %     subplot(122),ezmesh(z),view([145,90]),hold on,grid on,plot3(arr_present(:,1),arr_present(:,2),arr_present(:,3),'*'),hold off;
    ezmesh(z) ,hold on,grid on,plot3(arr_present(:,1),arr_present(:,2),arr_present(:,3),'*'),hold off;

    drawnow
    F(i)=getframe;

    %     ezmesh(z)
    % %     view([-37,90])
    %     hold on;
    %     grid on;
    %     %   plot(-0.0898,0.7126,'ro');
    %     plot3(arr_present(:,1),arr_present(:,2),arr_present(:,3),'*');                                                
    %    axis([-2*pi,2*pi,-pi,pi,-50,10]);
    %     hold off;
    pause(0.01);
    %     m(:,i) = getframe;        
    w = w_max-(w_max-w_min)*i/max_gen;
    %    fprintf('XXXXXXXXXXXXX\n',i);
    %    reset = 0;          
    if reset==1
        bit = 1;
        for k=1:part_size
            bit = bit&(range(arr_present(:,k))<0.1);
        end
        if bit==1       
            arr_present = ini_pos(pop_size,part_size);   
            v = ini_v(pop_size,part_size);           
            for k=1:pop_size                                  
                arr_present(k,end) = fitness(arr_present(k,1:part_size));
            end
            warning('this is the local max');    
            display(i);
        end
    end

    for j=1:pop_size
        v(j,:) = w.*v(j,:)+c1.*rand.*(pbest(j,1:part_size)-arr_present(j,1:part_size))+c2.*rand.*(gbest(1:part_size)-arr_present(j,1:part_size));                     

        
        c = find(abs(v)>6);                                                                                              
        v(c) = sign(v(c))*6;   

        arr_present(j,1:part_size) = arr_present(j,1:part_size)+v(j,1:part_size);              
        arr_present(j,end) = fitness(arr_present(j,1:part_size));

        if (arr_present(j,end)>pbest(j,end))&(Region_in(arr_present(j,:),region))    
            pbest(j,:) = arr_present(j,:);
        end

    end

    [best best_index] = max(arr_present(:,end));                                      

    if best>gbest(end)&(Region_in(arr_present(best_index,:),region))                  
        gbest = arr_present(best_index,:);
    end

    best_record(i) = gbest(end);
    display(i);
end

pso = gbest;

display(gbest);

% figure;
% plot(best_record);
% movie2avi(F,'pso_2D1.avi','compression','MSVC');


%   ***************************************************************************
%      evaluation 
%   ***************************************************************************
function fit = fitness(present)
fit=3*(1-present(1)).^2.*exp(-(present(1).^2) - (present(2)+1).^2) - 10*(present(1)/5 - present(1).^3 - present(2).^5).*exp(-present(1).^2-present(2).^2)- 1/3*exp(-(present(1)+1).^2 - present(2).^2);


function ini_present=ini_pos(pop_size,part_size)
ini_present = 3*rand(pop_size,part_size+1);        

function ini_velocity=ini_v(pop_size,part_size)
ini_velocity =3/2*(rand(pop_size,part_size));        


function flag=Region_in(pos_present,region)
[m n]=size(pos_present);
flag=1;
for j=1:n-1
    flag=flag&(pos_present(1:j)>=region(j,1))&(pos_present(1:j)<=region(j,2));
end


function arr_fitness=ini_fit(pos_present,pop_size,part_size)
for k=1:pop_size
    arr_fitness(k,1) = fitness(pos_present(k,1:part_size));  
end