lab matlab f

EPS=input('EPS=');
n=0;
while(n~=2);
n=input('n=');
end

a=zeros(n);
for i=1:n;
    fprintf('\n linia %g',i)
    a(i,:)=input(' ');
end
aa=a;
u=zeros(n);
q=eye(n);
format long e;
for k=1:n-2
    uk=zeros(n,1);
    sum=sqrt(a(k+1:n,k)'*a(k+1:n,k));
    if(a(k+1,k)>=0)
        semn=1;
    else
        semn=-1;
    end
    sigma=semn*sum;
    uk(k+1)=a(k+1,k)+sigma;
    uk(k+2:n)=a(k+2:n,k);
    beta=sigma*uk(k+1);
    if(beta==0)
        fprintf('\n beta-nul: STOP');
     return;
 end
 u=eye(n)-(uk*uk')/beta;
 a=u*a*u';
 q=u*q;
 fprintf('k=');
 k
  fprintf('a=');
  a
end
h=a;
 fprintf('\n forma superior Hassenberg',h);
 iter=0;
 flag=1;
 while(flag==1)
     iter=iter+1;
     miu=h(n,n);
     pt=eye(n);
     h=h-miu*eye(n);
     for k=1:n-1
         r=sqrt(h(k,k)^2+h(k+1,k)^2);
         if (r==0)
              fprintf('r=0:STOP');
              return;
          end
          ck=h(k,k)/r;
          dk=h(k+1,k)/r;
          p=eye(n);
          p(k,k)=ck;
          p(k+1,k)=-dk;
          p(k,k+1)=dk;
          p(k+1,k+1)=ck;
          h=p*h;
          pt=pt*p';
          q=p*q;
      end
      h=h*pt+miu*eye(n);
      for i=1:n-1;
          sum=(abs(h(i,i))+abs(h(i+1,i+1)))*EPS;
          if(abs(h(i+1,i))<=sum)
              h(i+1,i)=0;
          end
      end
      flag=0;
      i=1;
      while((i<=n-2)&&(flag==0))
          if((h(i+1,i)~=0)&&(h(i+2,i+1~0))
              flag=1;
          end
          i=i+1;
      end
      if(flag==0)
          i=1;
          while((h(i+1,i)~=0)
              ca=1;
              cb=-(h(i,i)+h(i+1,i+1));
              cc=h(i,i)*h(i+1,i+1)-h(i+1,i)*h(i,i+1);
              delta=cb*cb-4*ca*cc;
              if(delta>=0)
                  flag=1;
              end
              i=i+1;
          end
         fprintf('\n iter=',iter);
         s=h;
         fprintf('\n s=',s);
     end
     fprintf('\n forma canonica Schur:',s);
     qt=q';
     fprintf('\n matricea de transformare:',qt);
     ic=sqrt(-1);
     valp=zeros(1,n);
     vectp=zeros(n);
     j-1;
     while(j<=n-1)
         if(s(j+1,j)==0)
             valp(j)=s(j,j);
             vect(:,j)=qt(:,j)
             j=j+1;
         else
             ca=1;
             cb=-(s(j,j)+s(j+1,j+1));
             cc=s(j,j)*s(j+1,j+1)-s(j+1,j)*s(j,j+1);
             v=roots([ca cb cc]);
             valp(j)=v(1);
             valp(j+1)=v(2);
             vectp(:,j)=qt(:,j)+ic*qt(:,j+1);
             vectp(:,j+1)=qt(:,j)-ic*qt(:,j+1);
             j=j+2;
         end
         if(j==n)
             valp(j)=s(j,j);
             vectp(:,j)=qt(:,j);
         end
     end