如何将nxn矩阵转换为1x1矩阵（python）

Question

Adding values in the rows and columns of a nxn matrix how can I form a 1x1 matrix?

Answer 1

A scalar can be viewed as a 1x1 matrix.

If your matrix is a 2d - numpy array -> np.sum(mat) where mat is your matrix.

If your matrix is a list of lists -> sum([sum(x) for x in mat]) where mat is your matrix.

If you need sum per columns/rows I suggest you use numpy, with np.sum(mat, axis=AXIS) where AXIS tells whether you want sum for rows or columns.