python - Inserting one item on a matrix -

how insert single element array on numpy. know how insert entire column or row using insert , axis parameter. how insert/expand one.

for example, have array:

1 1 1 1 1 1 1 1 1 

how insert 0 (on same row), on (1, 1) location, say:

1 1 1 1 0 1 1 1 1 1 

is doable? if so, how do opposite (on same column), say:

1 1 1 1 0 1 1 1 1   1 

numpy has looks ragged arrays, arrays of objects, , not want. note difference in following:

in [27]: np.array([[1, 2], [3]]) out[27]: array([[1, 2], [3]], dtype=object)  in [28]: np.array([[1, 2], [3, 4]]) out[28]: array([[1, 2],        [3, 4]]) 

if want insert v row/column i/j, can padding other rows. easy do:

in [29]: = np.array([[1, 1, 1], [1, 1, 1], [1, 1, 1]])  in [30]: i, j, v = 1, 1, 3  in [31]: np.array([np.append(a[i_], [0]) if i_ != else np.insert(a[i_], j, v) i_ in range(a.shape[1])]) out[31]: array([[1, 1, 1, 0],        [1, 3, 1, 1],        [1, 1, 1, 0]]) 

to pad along columns, not rows, first transpose a, perform operation, transpose again.