Eigen vectors and eigen values in OpenCV

eigen_opencv.cpp

#include <opencv/cv.h>

// Input mat: 100 6-dimensional points
// Rows: 100 Cols: 6 Type: CV_F32
cv::Mat pt_mat;

cv::PCA pt_pca(pt_mat, cv::Mat(), CV_PCA_DATA_AS_ROW, 0);

// Mean
// Rows: 1 Cols: 6
cv::Mat pt_mean = pt_pca.mean;

// Eigen values
// In highest to lowest order
// Rows: 6 Cols: 1
cv::Mat pt_eig_vals = pt_pca.eigenvalues;

for (int i = 0; i < 6; ++i)
    std::cout << pt_eig_vals.at<float>(i, 0) << std::endl;

// Eigen vectors
cv::Mat pt_eig_vecs = pt_pca.eigenvectors;