采用全选主元的高斯—若当方法求矩阵的逆矩阵，矩阵阶数不限但要非奇异，只需在主函数中给出阶数和矩阵各元素即可-Select All PCA using the Gauss- Jordan method for matrix inverse matrix, the matrix order but are not limited to non-singular, just in the main function in the given order and matrix elements can