%遗传算法解决多目标函数规划
clear
clc
syms x;
%Function f1=f(x)
f1=x(:,1).*x(:,1)/4+x(:,2).*x(:,2)/4;
%function f2=f(x)
f2=x(:,1).*(1-x(:,2))+10;
NIND=100;
MAXGEN=50;
NV AR=2;
PRECI=20;
GGPA=0.9;
trace1=[];
trace2=[];
trace3=[];
FielD=[rep([PRECI],[1,NV AR]);[1,1;4,2];rep([1;0;1;1],[NV AR])]; Chrom=crtbp(NIND,NV AR*PRECI);
v=bs2rv(Chrom,FielD);
gen=1;
while gen<MAXGEN,
[NIND,N]=size(Chrom);
M=fix(NIND/2);
ObjV1=f1(v(1:M,:));
FitnV1=ranking(ObjV1);
SelCh1=select('sus',Chrom((M+1):NIND,:),FintV2,GGAP);
SelCh=[SelCh1;SelCh2];
SelCh=recombin('xovsp',SelCh,0.7);
Chrom=mut(SelCh);
v=bs2rv(Chrom,FielD);
trace1(gen,1)=min(f1(v));
trace1(gen,2)=sum(f1(v))/length(f1(v));
trace2(gen,1)=min(f2(v));
trace2(gen,2)=sum(f2(v))/length(f2(v));
trace3(gen,1)=min(f1(v)+f2(v));
trace3(gen,2)=sum(f1(v))/length(f1(v))+sum(f2(v))/length(f2(v));
gen=gen+1;
end
figure(1);
clf;
plot(trace1(:,1));
hold on;
plot(trace1(:,2),'-.');
plot(trace1(:,1),'.');
plot(trace1(:,2),'.');
grid;
legend('解的变化','种群均值的变化'); xlabel('迭代次数');
ylabel('目标函数值');
figure(2);
clf;
plot(trace2(:,1));
hold on;
plot(trace2(:,2),'-.');
plot(trace2(:,1),'.');
plot(trace2(:,2),'.');
grid;
legend('解的变化','种群均值的变化'); xlabel('迭代次数');
ylabel('目标函数值');
figure(3);
clf;
plot(trace3(:,1));
hold on;
plot(trace3(:,2),'-.');
plot(trace3(:,1),'.');
plot(trace3(:,2),'.');
grid;
legend('解的变化','种群均值的变化'); xlabel('迭代次数');
ylabel('目标函数值');
figure(4);
clf;
plot(f1(v));
hold on;
plot(f2(v),'r-.');
grid;。