1MatrixXf M1(2,6); // Column-major storage 2M1 << 1, 2, 3, 4, 5, 6, 3 7, 8, 9, 10, 11, 12; 4 5Map<MatrixXf> M2(M1.data(), 6,2); 6cout << "M2:" << endl << M2 << endl;