Insert 2D array into 3D array in python

Question

Lets say I make the following arrays:

>>> a = zeros((2,2,2))
>>> b = ones((2,2))

How can I insert b into the middle of a? So my resulting array will look like

array([[[ 0.,  0.],
        [ 0.,  0.]],

       [[ 1.,  1.],
        [ 1.,  1.]],

       [[ 0.,  0.],
        [ 0.,  0.]]])

How does a 2x2x2 array end up with 12 elements? It should only have 8 elements. Where do you want to insert the array? How do you define "middle"? — enumaris
– enumaris, Commented Apr 4, 2018 at 20:40

llllllllll · Accepted Answer · 2018-04-04 20:41:25Z

3

a = np.insert(a, 1, b, axis=0)

answered Apr 4, 2018 at 20:41

llllllllll

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1 Comment

ahh, i had tried this but didn't putthe axis = 0 at the end

Mohsen Hrt · Accepted Answer · 2020-04-17 01:50:35Z

0

A way to show same as your result is using tuple. code:

b = numpy.ones((2,2))
a = numpy.zeros((2, 2))
tpl = a,
tpl = b,
tpl = a,

So you can consider it as 3dArray and also you can use for loop to add multi array into it.Hope be helpfull.

answered Apr 16, 2020 at 17:06

Mohsen Hrt

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James Carter · Accepted Answer · 2018-04-04 20:41:38Z

-1

a=np.zeros((3,2,2))
b=np.ones((2,2))

a[1]=b*1

That will produce your output.

answered Apr 4, 2018 at 20:41

James Carter

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