%%%%%%%%%%%%%%%%%差分进化算法求函数极值%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%初始化%%%%%%%%%%%%%%%%%%%%%%%%%
clear all; %清除所有变量
close all; %清图
clc; %清屏
NP=50; %个体数目
D=10; %变量的维数
G=200; %最大进化代数
F0=0.4; %初始变异算子
CR=0.1; %交叉算子
Xs=20; %上限
Xx=-20; %下限
yz=10^-6; %阈值
%%%%%%%%%%%%%%%%%%%%%%%%%赋初值%%%%%%%%%%%%%%%%%%%%%%%%
x=zeros(D,NP); %初始种群
v=zeros(D,NP); %变异种群
u=zeros(D,NP); %选择种群
x=rand(D,NP)*(Xs-Xx)+Xx; %赋初值
%%%%%%%%%%%%%%%%%%%%计算目标函数%%%%%%%%%%%%%%%%%%%%
for m=1:NP
Ob(m)=func1(x(:,m));
end
trace(1)=min(Ob);
%%%%%%%%%%%%%%%%%%%%%%%差分进化循环%%%%%%%%%%%%%%%%%%%%%
for gen=1:G
%%%%%%%%%%%%%%%%%%%%%%变异操作%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%自适应变异算子%%%%%%%%%%%%%%%%%%%
lamda=exp(1-G/(G+1-gen));
F=F0*2^(lamda);
%%%%%%%%%%%%%%%%%r1,r2,r3和m互不相同%%%%%%%%%%%%%%%%
for m=1:NP
r1=randint(1,1,[1,NP]);
while (r1==m)
r1=randint(1,1,[1,NP]);
end
r2=randint(1,1,[1,NP]);
while (r2==m)|(r2==r1)
r2=randint(1,1,[1,NP]);
end
r3=randint(1,1,[1,NP]);
while (r3==m)|(r3==r1)|(r3==r2)
r3=randint(1,1,[1,NP]);
end
v(:,m)=x(:,r1)+F*(x(:,r2)-x(:,r3));
end
%%%%%%%%%%%%%%%%%%%%%%交叉操作%%%%%%%%%%%%%%%%%%%%%%%
r=randint(1,1,[1,D]);
for n=1:D
cr=rand(1);
if (cr<=CR)|(n==r)
u(n,:)=v(n,:);
else
u(n,:)=x(n,:);
end
end
%%%%%%%%%%%%%%%%%%%边界条件的处理%%%%%%%%%%%%%%%%%%%%%
for n=1:D
for m=1:NP
if (u(n,m)<Xx)|(u(n,m)>Xs)
u(n,m)=rand*(Xs-Xx)+Xx;
end
end
end
%%%%%%%%%%%%%%%%%%%%%%选择操作%%%%%%%%%%%%%%%%%%%%%%%
for m=1:NP
Ob1(m)=func1(u(:,m));
end
for m=1:NP
if Ob1(m)<Ob(m)
x(:,m)=u(:,m);
end
end
for m=1:NP
Ob(m)=func1(x(:,m));
end
trace(gen+1)=min(Ob);
if min(Ob(m))<yz
break
end
end
[SortOb,Index]=sort(Ob);
x=x(:,Index);
X=x(:,1); %最优变量
Y=min(Ob); %最优值
%%%%%%%%%%%%%%%%%%%%%%%%%画图%%%%%%%%%%%%%%%%%%%%%%%%%%
figure
plot(trace);
xlabel('迭代次数')
ylabel('目标函数值')
title('适应度进化曲线')
