1*bf2c3715SXin Li Matrix3d m = Matrix3d::Zero(); 2*bf2c3715SXin Li m(0,2) = 1e-4; 3*bf2c3715SXin Li cout << "Here's the matrix m:" << endl << m << endl; 4*bf2c3715SXin Li cout << "m.isZero() returns: " << m.isZero() << endl; 5*bf2c3715SXin Li cout << "m.isZero(1e-3) returns: " << m.isZero(1e-3) << endl; 6