How to get a sub-shape of an array in Python?

Question

Not sure the title is correct, but I have an array with shape (84,84,3) and I need to get subset of this array with shape (84,84), excluding that third dimension.

How can I accomplish this with Python?

What do you mean 'excluding that third dimension'? You need to specify exactly which subset you want. If you are using `numpy` for example, this would be very easy. — mapf, May 25 '20 at 08:04

score 2 · Accepted Answer · answered May 25 '20 at 08:06

2

your_array[:,:,0]

This is called slicing. This particular example gets the first 'layer' of the array. This assumes your subshape is a single layer.

answered May 25 '20 at 08:06

Simon Notley

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score 1 · Answer 2 · answered May 25 '20 at 08:10

If you are using numpy arrays, using slices would be a standard way of doing it:

import numpy as np

n = 3  # or any other positive integer
a = np.empty((84, 84, n))

i = 0  # i in [0, n]
b = a[:, :, i]

print(b.shape)

I recommend you have a look at this.

How to get a sub-shape of an array in Python?

2 Answers2