eigen/unsupported/doc/examples/MatrixPower_failure.cpp

21 lines
395 B
C++

#include <unsupported/Eigen/MatrixFunctions>
#include <iostream>
int main()
{
Eigen::Matrix4d A;
A << 0, 0, 2, 3,
0, 0, 4, 5,
0, 0, 6, 7,
0, 0, 8, 9;
std::cout << A.pow(0.37) << std::endl;
// The 1 makes eigenvalue 0 non-semisimple.
A.coeffRef(0, 1) = 1;
// This fails if EIGEN_NO_DEBUG is undefined.
std::cout << A.pow(0.37) << std::endl;
return 0;
}