Question

Write a function in Matlab that takes as input the number of iterations k, the size n, and a sparse matrix A. Have this function run the Power method for k iterations on an initial guess the vector of 1’s and output the dominant eigenvalue and its corresponding eigenvector. Use only basic programming.

Write out or print out your function.

Answer 1

Ans :

function [m, n] = PowerMethod (k, A, n)
   for i = 1:k
        m1 = zeros(n,1);
        for j = 1:n
            for q = 1:n
                m1(j) = m1(j) + A(j,q) * m(q);
            end
        end
       n = 0;
        for j = 1:n
            if abs(m1(j)) > abs(n)
                n = m1(j);
            end
        end
        m = m1 / n;
    end
end