How to read/write a PCA object from/to a cv::FileStorage ?

edit

You have to save mean , eigen vectors & eigen values Matrix.

void save(const string &file_name,cv::PCA pca_)
{
    FileStorage fs(file_name,FileStorage::WRITE);
    fs << "mean" << pca_.mean;
    fs << "e_vectors" << pca_.eigenvectors;
    fs << "e_values" << pca_.eigenvalues;
    fs.release();
}

int load(const string &file_name,cv::PCA pca_)
{
    FileStorage fs(file_name,FileStorage::READ);
    fs["mean"] >> pca_.mean ;
    fs["e_vectors"] >> pca_.eigenvectors ;
    fs["e_values"] >> pca_.eigenvalues ;
    fs.release();

}