说明：  在稀疏表示问题中，给定一个字典，OMP算法可以以较快的收敛速度和较少的迭代次数实现稀疏编码矩阵（稀疏系数矩阵）的求解。
(In the sparse representation problem, given a dictionary, OMP algorithm can solve the sparse coding matrix (sparse coefficient matrix) with faster convergence speed and fewer iterations.)