1MatrixXf matA(2,2), matB(2,2); 2matA << 2, 0, 0, 2; 3 4// Simple but not quite as efficient 5matB = matA * matA; 6cout << matB << endl << endl; 7 8// More complicated but also more efficient 9matB.noalias() = matA * matA; 10cout << matB; 11