矩阵中非零元素的个数远远小于矩阵元素的总数，并且非零元素的分布没有规律，则称该矩阵为稀疏矩阵(sparse matrix) 与之相区别的是，如果非零元素的分布存在规律(如上三角矩阵、下三角矩阵、对称矩阵)，则称该矩阵为特殊矩阵。-Matrix china-africa zero element number is far less than the total number of matrix element, and the distribution of the non-zero elements, and says that the matrix of the sparse matrix (sparse matrix). And the difference is that if non-zero element distribution exist law (such as triangle matrix, lower triangular matrix and symmetric matrix), has described the matrix as a special matrix.