flch4eg3.m

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clear
p=rand(2,1);
wij0=rand(6,2);wij1=rand(6,2);
wjk0=rand(1,6);wjk1=rand(1,6);E=0.005;a=0.8;b=0.9;z=0.3;g=0.9;
N=1;x=-1.25;y=-1.25;e=3.141592;
for m=1:3000
  
  yd=0.8*(x^2/a^2-y^2/b^2);yn(N)=yd;
  x=x+0.001;y=y+0.001;
       for t=1:10
        oi=p;
        netj=wij0*p;
        for  l=1:6
        oj(l,1)=1/(1+e^(-netj(l,1)));
    end
        netk=wjk0*oj; 
        ok=1/(1+e^(-netk));ko(N)=ok;
        sk=ok*(1-ok)*(yd-ok);
        sj=oj'*(1-oj)*sk*wjk0;
        wij2=wij1+g*sj'*oi'+z*[wij1-wij0];
        wij0=wij1;wij1=wij2;
        wjk2=wjk1+g*sk*oj'+z*[wjk1-wjk0];
        wjk0=wjk1;wjk1=wjk2;
        c=0.5*(yd-ok)^2;q(N)=c;
        while   c<E    break
        end
       
     end
  
    N=N+1;
end
m=0.1:0.1:5;
n=0.1:0.1:5;
[m,n]=meshgrid(m,n);   N=1;
for k=1:50
    for d=1:50
     yy(k,d)=yn(N);
     oo(k,d)=ko(N);
     ee(k,d)=q(N);
     N=N+1;
 end
end
 wij0,wij2,wjk0,wjk2
subplot(2,2,1);
surf(m,n,yy);
xlabel('m');
ylabel('n');
zlabel('yy');
title('期望值');
    subplot(2,2,2);
   surf(m,n,oo);
   xlabel('m');
ylabel('n');
zlabel('oo');
title('训练值');
    subplot(2,1,2);
     surf(m,n,ee);
     xlabel('m');
ylabel('n');
zlabel('ee');
title('误差');