def test_row_col_del():
e = DenseMatrix(3, 3, [1, 2, 3, 4, 5, 6, 7, 8, 9])
raises(IndexError, lambda: e.row_del(5))
raises(IndexError, lambda: e.row_del(-5))
raises(IndexError, lambda: e.col_del(5))
raises(IndexError, lambda: e.col_del(-5))
assert e.row_del(-1) == DenseMatrix([[1, 2, 3], [4, 5, 6]])
assert e.col_del(-1) == DenseMatrix([[1, 2], [4, 5]])
e = DenseMatrix(3, 3, [1, 2, 3, 4, 5, 6, 7, 8, 9])
assert e.row_del(1) == DenseMatrix([[1, 2, 3], [7, 8, 9]])
assert e.col_del(1) == DenseMatrix([[1, 3], [7, 9]])
