1*bf2c3715SXin Li Matrix4d X = Matrix4d::Random(4,4); 2*bf2c3715SXin Li Matrix4d A = X + X.transpose(); 3*bf2c3715SXin Li cout << "Here is a random symmetric 4x4 matrix:" << endl << A << endl; 4*bf2c3715SXin Li Tridiagonalization<Matrix4d> triOfA(A); 5*bf2c3715SXin Li Vector3d hc = triOfA.householderCoefficients(); 6*bf2c3715SXin Li cout << "The vector of Householder coefficients is:" << endl << hc << endl; 7