function eigplot(file,n)
% This function plots response of the dominant eigenvalue to changes in matrix elements
% and finds the element value that produces dominant eigenvalue == 1
% file - matrix
% n - number of stages

factor = [0.02 0.05 0.1 0.2 0.5 0.7 1 1.5 2 3 5 10 15 20];
factordiag=0.4;
ifplot = 1; %change as you wish (1 plots, 0 does not)
fid=fopen(file,'r');
a1=fscanf(fid,'%f',[n, n]);
a1=transpose(a1);
for i1=1:n
   for j1=1:n
      alleig=0;
      allelem=0;
      a=a1;
      if (a(i1,j1) > 0)
        if (i1 ~= j1)
           for t = 1:10
              if (a1(i1,j1) * factor(t) < 1)
                 a(i1,j1) = a1(i1,j1) * factor(t);
                 temp=eig(a);
                 [w,d] = eig(a);
                 d=diag(d);
                 imax = find(d==max(d));
                 alleig(t) = temp(imax);
                 allelem(t) = a(i1,j1); 
              end
           end
        
       
        else 
           for t = 1:10
              if (1 - (1-a1(i1,j1)) * factor(t) * factordiag) > 0
                 a(i1,j1) = 1 - (1-a1(i1,j1)) * factor(t) * factordiag;
                 temp = eig(a);
                 [w,d] = eig(a);
                 d=diag(d);
                 imax = find(d==max(d));
                 alleig(t) = temp(imax);
                 allelem(t) = a(i1,j1);
              end
           end
             
        end
        %alleig
        %allelem
        %lambda_equal_1_for = [i1 j1 a1(i1,j1) interp1(alleig,allelem,1)]
        if (ifplot == 1)
           figure;
           plot(allelem,alleig);
           TITLE(sprintf('i: %1d  j: %1d',i1,j1));
        end
      end
   end
end
fclose(fid);