This is a file

function [Q,H] = Arnoldi(A,k,b);
m = length(b);
H = zeros(k);
Q = zeros(m,k);

Q(:,1) = b/norm(b);
for n = 1:k,
v=A*Q(:,n);
for j=1:n
H(j,n)=Q(:,j)'*v;
v=v-H(j,n)*Q(:,j);
end
H(n+1,n)=norm(v);
Q(:,n+1)=v/H(n+1,n);
end