Nougat 7.0  |  7.0.0_r31
C++程序  |  4行  |  160 B 

MatrixXd ones = MatrixXd::Ones(3,3);
VectorXcd eivals = ones.eigenvalues();
cout << "The eigenvalues of the 3x3 matrix of ones are:" << endl << eivals << endl;