matlab-VPSO搜索三维曲面的最小值的matlab仿真（包含教程）

clc;clear all;close all; %% initialization % swarm_size = 64; % number of the swarm particles maxIter = 50; % maximum number of iterations inertia = 1.0; correction_factor = 2.0; % set the position of the initial swarm a = 1:8; [X,Y] = meshgrid(a,a); C = cat(2,X',Y'); D = reshape(C,[],2); swarm(1:swarm_size,1,1:2) = D; % set the position of the particles in 2D swarm(:,2,:) = 0; % set initial velocity for particles swarm(:,4,1) = 1000; % set the best value so far plotObjFcn = 1; % set to zero if you do not need a final plot %% define the objective funcion here (vectorized form) objfcn = @(x)(x(:,1) - 20).^2 + (x(:,2) - 25).^2; tic; %% The main loop of PSO for iter = 1:maxIter swarm(:, 1, 1) = swarm(:, 1, 1) + swarm(:, 2, 1)/1.3; %update x position with the velocity swarm(:, 1, 2) = swarm(:, 1, 2) + swarm(:, 2, 2)/1.3; %update y position with the velocity x = swarm(:, 1, 1); % get the updated position y = swarm(:, 1, 2); % updated position fval = objfcn([x y]); % evaluate the function using the position of the particle % compare the function values to find the best ones for ii = 1:swarm_size if fval(ii,1) < swarm(ii,4,1) swarm(ii, 3, 1) = swarm(ii, 1, 1); % update best x position, swarm(ii, 3, 2) = swarm(ii, 1, 2); % update best y postions swarm(ii, 4, 1) = fval(ii,1); % update the best value so far end end [~, gbest] = min(swarm(:, 4, 1)); % find the best function value in total % update the velocity of the particles swarm(:, 2, 1) = inertia*(rand(swarm_size,1).*swarm(:, 2, 1)) + correction_factor*(rand(swarm_size,1).*(swarm(:, 3, 1) ... - swarm(:, 1, 1))) + correction_factor*(rand(swarm_size,1).*(swarm(gbest, 3, 1) - swarm(:, 1, 1))); %x velocity component swarm(:, 2, 2) = inertia*(rand(swarm_size,1).*swarm(:, 2, 2)) + correction_factor*(rand(swarm_size,1).*(swarm(:, 3, 2) ... - swarm(:, 1, 2))) + correction_factor*(rand(swarm_size,1).*(swarm(gbest, 3, 2) - swarm(:, 1, 2))); %y velocity component % plot the particles clf;plot(swarm(:, 1, 1), swarm(:, 1, 2), 'bx'); % drawing swarm movements axis([-2 40 -2 40]); pause(.1); % un-comment this line to decrease the animation speed disp(['iteration: ' num2str(iter)]); end toc %% plot the function if plotObjFcn ub = 40; lb = 0; npoints = 1000; x = (ub-lb) .* rand(npoints,2) + lb; for ii = 1:npoints f = objfcn([x(ii,1) x(ii,2)]); plot3(x(ii,1),x(ii,2),f,'.r');hold on end plot3(swarm(1,3,1),swarm(1,3,2),swarm(1,4,1),'xb','linewidth',5,'Markersize',5);grid end