“…Covariance matrix is an important tool which is widely used in studying noise [1][2], direction-ofarrival [3][4][5], error distribution [6], allocation strategies [7], image analysis [8], power state estimation [9], local path planning [10], human activity recognition [11], geomagnetic jerk [12], the qualities of software and the sustainable innovation ability of enterprises [13][14][15], etc.. An important feature of the ML approach is that it has robust performance in noise environment by treating the covariance matrix of the additive Gaussian noise as a parameter [2]. In the image matching algorithm, The gradient magnitudes, direction, corrosion, expansion and information entropy and so forth, the feature of the target image can be reconciled with their covariance matrix to construct a new characteristic model [8].…”