convert 3D list to numpy array

Question

I want to convert a 3D list to a numpy array.

When i am trying to do that using np.array(list) or np.asarray(list) it is giving 2D numpy array of shape (6,10).

How can I get numpy array of 3 dimensional(like shape should be (6,10,10). Can someone help me resolving this issue.

The list i am trying to convert is mentioned below

[[[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]]
[[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L] [4L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]]
[[0L, 1L, 2L] [0L, 1L, 2L] [0L, 1L, 2L] [0L, 1L, 2L, 3L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]]
[[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]]
[[0L, 1L, 2L, 3L] [0L, 1L, 2L, 3L] [0L, 1L, 2L, 3L] [0L, 1L, 2L, 3L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]]
[[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]
[0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L]]]

Alber8295 · Accepted Answer · 2017-12-25 12:53:50Z

3

If you build a 2D list and convert it to numpy with np.array() it will return a numpy array with 2 dimensions.

If you build a 3D list and convert it to numpy with np.array() it will return a numpy array with 3 dimensions.

Minimal working example:

my_list = [[[0,1,2],[0,1,2]],[[0,1,2],[0,1,2]]]
my_list

[[[0, 1, 2], [0, 1, 2]], [[0, 1, 2], [0, 1, 2]]]

my_np_array = np.array(my_list)
my_np_array.shape

(2, 2, 3)

answered Dec 25, 2017 at 12:53

Alber8295

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HDunn · Accepted Answer · 2017-12-25 12:28:39Z

1

That's because this is not a 3D list. List has format [item,item]; 2D list would be [[],[]]. There are no inner level separators(',') in the file above. Load it into python and you get a 6,10 tuple back, the first valid entry after which no commas, so error out.

answered Dec 25, 2017 at 12:28

HDunn

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heisenberg · Accepted Answer · 2023-08-12 16:19:46Z

0

Your list is not a homogeneous list, so it gives error when creating you matrix. Each dimension that u create must be equal size.

answered Aug 12, 2023 at 16:19

heisenberg

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