clear all;

N=4*10^4;

delta=0.1;

DD=0.1;
DD=[0,0.1,0.5,1,10];

for id=1:length(DD);
    
    D=DD(id);
    
    B=2*D*[-1,1;1,-1];


    lambda=zeros(N,1);t=lambda;

    x=randn(2,1);x=x/norm(x);


for in=1:10;


for it=1:N;

    t(it)=it*delta;

     a1=randn(1);a2=randn(1);
     A=[a1,0;0,a2];

     AE=expm((A+B)*delta);
     y=AE*x;
     g=norm(y);
     x=y/norm(y);
     if it>1;
         lambda(it)=log(g)/t(it)+lambda(it-1)*(1-1/it);
     else;
         lambda(it)=g/delta;
     end;
     
     if rem(it,200)==0;
         figure(4)
         plot(t(100:it),lambda(100:it),'k',t(1:it),0*t(1:it))
         drawnow;
     end;
     
     end;

     
     liapun(in,id)=lambda(N);
     
end;
end;