9 MatrixXd
A = MatrixXd::Random(100,100);
10 MatrixXd
b = MatrixXd::Random(100,50);
11 MatrixXd
x =
A.fullPivLu().solve(
b);
12 double relative_error = (
A*
x -
b).norm() /
b.norm();
13 cout <<
"The relative error is:\n" << relative_error << endl;