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close all;
clc;
clear;
rand('seed',1);%保证每次的随机数结果一样
%------------------参数初始化------------------
wolf_num = 15; % 狼群数量
max_iter = 150; % 最大迭代次数
dim = 30; % 变量维数
lb = -30*ones(1,dim); % 自变量下边界
ub = 30*ones(1,dim); % 自变量上边界
alpha_pos = zeros(1,dim); %"alpha" 狼只位置初始化
alpha_score = inf; % "alpha"狼只适应度函数初始化
beta_pos = zeros(1,dim); % "beta" 狼只位置初始化
beta_score = inf; % "beta"狼只适应度函数初始化
delta_pos = zeros(1,dim); % "delta"狼只位置初始化
delta_score = inf; % "delta"狼只适应度函数初始化
convergence_curve = zeros(1,max_iter); % 每次迭代的最小适应度值初始化
%------------------参数初始化------------------
count = 0;
position = init_pos(wolf_num,dim,ub,lb); % 狼群位置初始化
while count < max_iterfor i = 1:wolf_numflag_ub = position(i,:) > ub;%判断代表狼只位置的30维向量的第几维超出上边界,flag_ub为30维的布尔型,超出记为1,否则为0。flag_lb = position(i,:) < lb;%判断代表狼只位置的30维向量的第几维超出下边界,flag_lb为30维的布尔型,超出记为1,否则为0。%%%%%假设position(1:)=[40,-40,20,20,……],则flag_ub=[1,0,0,0……],flag_lb=[0,1,0,0……]position(i,:) = position(i,:).*(~(flag_ub+flag_lb))+flag_ub.*ub+flag_lb.*lb; % 调整超出边界的狼群位置,将超出的部分限制在上边界和下边界fitness = f(position(i,:)); % 计算适应度值if fitness < alpha_score %更新alphe的适应度值alpha_score = fitness;alpha_pos = position(i,:);elseif fitness < beta_score%更新beta的适应度值beta_score = fitness;beta_pos = position(i,:);elseif fitness < delta_score%更新delta的适应度值delta_score = fitness;delta_pos = position(i,:);endenda = 2 - count*(2/max_iter); % 更新a的值,a为线性for i = 1:wolf_numfor j = 1:dimalpha = update_pos(alpha_pos(j),position(i,j),a);%更新alpha、beta、delta狼只位置beta = update_pos(beta_pos(j),position(i,j),a);delta = update_pos(delta_pos(j),position(i,j),a);position(i,j) = (alpha+beta+delta)/3;endendcount = count + 1;convergence_curve(count) = alpha_score;
end
%-----------------------------绘图-------------------------------------
plot(1:max_iter,convergence_curve,'LineWidth',2,'LineStyle','-','Color','r');
xlabel('iteration'); ylabel('fitness'); title('GWO fitness curve');
grid on;
disp('The solution of GWO:'); disp(alpha_pos);
disp('The best fitness of GWO:'); disp(alpha_score);
%-----------------------------绘图-------------------------------------%-----------------------------适应度函数-------------------------------
function res = f(x)
% f_min : 0
dim = 30; sum = 0;
for i = 1:dim-1sum = sum + 100*(x(i+1)-x(i)^2)^2+(x(i)-1)^2;
end
res = sum;
end
%-----------------------------适应度函数-------------------------------
%-----------------------------更新A、C和位置-------------------------------
function res = update_pos(v1,v2,a)
A = 2*a*rand()-a;
C = 2*rand();
temp = abs(C*v1-v2);
res = v1 - A*temp;
end
%-----------------------------更新A、C和位置-------------------------------
%-----------------------------位置初始化函数-------------------------------
function position = init_pos(wolf_num,dim,ub,lb)
position = zeros(wolf_num,dim);
for i = 1:wolf_numfor j = 1:dimposition(i,j) = rand( )*(ub(j)-lb(j)) + lb(j);end
end
end
%-----------------------------位置初始化函数-------------------------------
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