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