#include <highfive/highfive.hpp>

#include <highfive/eigen.hpp>

// Example showing reading and writing of `Eigen::Matrix`. Using

// `Eigen::Matrix` as an example, but `Eigen::Array` works analogously.

//

// Both `Eigen::Vector` and `Eigen::Map` have their own examples.

int main() {

HighFive::File file("eigen_vector.h5", HighFive::File::Truncate);

// Create a matrix.

Eigen::VectorXd v(3);

v << 1, 2, 3;

std::cout << "v = \n" << v << "\n\n";

// Write it to the file:

file.createDataSet("col_vec", v);

// The twist is that Eigen typedefs:

// using VectorXd = Matrix<double, Dynamic, 1>;

//

// Therefore, for HighFive it's indistinguishable from a Nx1 matrix. Since,

// Eigen distinguishes row and column vectors, the HighFive chooses to

// respect the distinction and deduces the shape of vector as Nx1.

// ... and read it back as fixed-size:

auto w = file.getDataSet("col_vec").read<Eigen::Vector3d>();

std::cout << "w = \n" << w << "\n";

return 0;

}