1 MatrixXf A(MatrixXf::Random(5,3)), thinQ(MatrixXf::Identity(5,3)), Q; 2 A.setRandom(); 3 HouseholderQR<MatrixXf> qr(A); 4 Q = qr.householderQ(); 5 thinQ = qr.householderQ() * thinQ; 6 std::cout << "The complete unitary matrix Q is:\n" << Q << "\n\n"; 7 std::cout << "The thin matrix Q is:\n" << thinQ << "\n\n"; 8