Eigen3中两个矩阵的Frobenius内积

#include <iostream>
#include <Eigen/Dense>

int main() {
    Eigen::Matrix3d matrix1;
    matrix1 << 1, 2, 3,
               4, 5, 6,
               7, 8, 9;

    Eigen::Matrix3d matrix2;
    matrix2 << 9, 8, 7,
               6, 5, 4,
               3, 2, 1;

    double frobeniusProduct = (matrix1.cwiseProduct(matrix2)).sum();

    std::cout << "Frobenius inner product: " << frobeniusProduct << std::endl;

    return 0;
}