Before revision:  This method, benchmarked on synthetic datasets as well as on some S P500 stock returns covariance matrices ,  achieves comparable results to several state-of-the-art techniques, while outperforming all existing algorithms in terms of computational time. Finally, theoretical results concerning the convergence of the training are derived .
After revision:  This method, benchmarked on synthetic datasets as well as on some S P500 stock returns covariance matrices , achieves comparable results to several state-of-the-art techniques, while outperforming all existing algorithms in terms of computation time .