1 #include <unsupported/Eigen/MatrixFunctions>
2 #include <iostream>
3 
4 using namespace Eigen;
5 
main()6 int main()
7 {
8   const double pi = std::acos(-1.0);
9 
10   MatrixXd A(2,2);
11   A << cos(pi/3), -sin(pi/3),
12        sin(pi/3),  cos(pi/3);
13   std::cout << "The matrix A is:\n" << A << "\n\n";
14   std::cout << "The matrix square root of A is:\n" << A.sqrt() << "\n\n";
15   std::cout << "The square of the last matrix is:\n" << A.sqrt() * A.sqrt() << "\n";
16 }
17