medium2_matrix_part2_010.md

matrix.py

def neg(mat, inplace = False):
    if inplace:
        for i in range(len(mat)):
            for j in range(len(mat[0])):
                mat[i][j] = -mat[i][j]
        return None
    else:
        res = []
        for i in range(len(mat)):
            row = []
            for j in range(len(mat[0])):
                row.append(-mat[i][j])
            res.append(row)
        return res

Test Code

import matrix

mat1 = matrix.create_linear_matrix(3,3)

mat2 = matrix.add_scalar(matrix.ones(3,3), 2)

mat3 = matrix.sub(mat1, mat2)

print("Mat3 Before:")
matrix.print_matrix(mat3)

mat4 = matrix.neg(mat3)
print("\nMat4:")
matrix.print_matrix(mat4)

print("\nMat3 with inplace True:")
matrix.neg(mat3, inplace = True)
matrix.print_matrix(mat3)

Output
Mat3 Before:
-2 -1 0
1 2 3
4 5 6

Mat4:
2 1 0
-1 -2 -3
-4 -5 -6

Mat3 with inplace True:
2 1 0
-1 -2 -3
-4 -5 -6