Introduction - If you have any usage issues, please Google them yourself
Sparse matrix, there is no a clear definition, but is generally believed that non-zero elements of sparse matrix is less than zero elements, and not necessarily the law of the distribution matrix. In the matrix calculation and input-output matrix, the most convenient way to store two-dimensional array of matrix compression can not be simplified matrix calculation on the input and output can not facilitate, and reduce the computing time complexity algorithm primarily related to general matrix compression on the complexity of its operations will increase. So the answer is to save storage space.