How to repeat the inner row of a 3D matrix(NxMxV) to get a new matrix(Nx2MxV) using np.repeat?

Question

Here is an example of what I want:

original matrix:
[[[5 1 4]]

 [[0 9 5]]

 [[8 0 9]]]
matrix I want:
[[[5 1 4]
  [5 1 4]]

 [[0 9 5]
 [0 9 5]]

 [[8 0 9]
 [8 0 9]]]

I have tried np.repeat(A, 2, axis=0), which apparently does not work since it gives the output:

[[[5 1 4]]

 [[5 1 4]]

 [[0 9 5]]

 [[0 9 5]]

 [[8 0 9]]]

Answer 1

You want to repeat on axis=1:

np.repeat(A, 2, axis=1)

Output:

array([[[5, 1, 4],
        [5, 1, 4]],

       [[0, 9, 5],
        [0, 9, 5]],

       [[8, 0, 9],
        [8, 0, 9]]])

NB. remember to check the shape of your arrays: A.shape -> (3, 1, 3). You want to make it (3, 2, 3), not (6, 1, 3).