MATLAB code for Conjugate gradient method

function [x]= conjugate_gradient_method(A,b,x)

    r0=b-A*x;% A is a square matrix of nxn and x is a vector of nx1

             % b is also a vector of nx1 order

             % equation is of form AX=B

    d=r0;

    for i= 1:length(b)

        alpha = (r0'*r0)/(d'*A*d);fprintf('alpha = %f\n\n',alpha);

        x = x + alpha * d;fprintf('x = %f\n',x);fprintf('\n');

        r1 = r0 - alpha * A * d;fprintf('r = %f\n',r1);fprintf('\n');

        if sqrt(r1'*r1)< 1e-10

            break;

        end

        beta = (r1'*r1)/(r0'*r0);fprintf('beta = %f\n',beta);fprintf('\n');

        d = r1 + beta * d;fprintf('d = %f\n',d);fprintf('\n');

        r0 = r1;

        fprintf('----------------------------------\n\n');

    end

end