esprit算法对有干扰的信号频率进行估计,该函数用来计算任意函数的一阶偏导数(数值方法),结合PCA的尺度不变特征变换(SIFT)算法。- esprit algorithm signal frequency interference can be assessed This function is used to calculate the arbitrary function of the first order partial derivative (numerical methods), Combined with PCA scale invariant feature transform (SIFT) algorithm.