Introduction - If you have any usage issues, please Google them yourself
(1) design matrix and write on behalf of the Matrix class. This category includes the number of variables int rows matrix ranks and int cols, matrix array of data double data [][], constructor Matrix (), Matrix (int rows, int cols), Matrix (int rows, int cols, double data [] []) method to obtain the value of an element getData (int row, int col), set the value of an element of the method setData (int row, int col, double value), the calculation of two matrices method multiply (Matrix m) and toString () and so on.