function [v,a] = power_method (U,toll)

[x,~] = size(U);
for i=1:x
    v(i)=1;
end
v=v';

err = inf;
while err > toll
    
    v1=U*v;
    v1=v1./norm(v1,inf);
    err = norm(v1-v,inf);
    a = v1./v;
    v=v1;
    
end


 
end