3-dimensional array

Example a=[1 0;0 1] b=[2 2;2 2] c=[0 3;3 0] d=cat(3,a,b,c) ==> d(:,:,1)=a ; d(:,:,2)=b; d(:,:,3)=c.

I have n-dimensional arrays are the same size, I want to merge into a 3-dimensional array. I have known about the "cat" function to concatenates into 3-dimensional array such as example , but not understand much about how to use it to solve my problem

[Andrew Newell]

Can n be greater than 3?

[Oleg Komarov]

@yen: Do you have a question?

Answer 1

[Leepakshi]

Hi Yen,

To merge multiple n-dimensional arrays of identical size into a single 3-dimensional array, the cat function in MATLAB can be utilized. This function concatenates arrays along a specified dimension.

For example, given 2D arrays a, b, and c, the command cat(3, a, b, c) will concatenate these arrays along the third dimension, resulting in a 3D array. Each slice of the 3D array corresponds to one of the original arrays.

% Define the 2D arrays 
a = [1 0; 0 1]; 
b = [2 2; 2 2]; 
c = [0 3; 3 0]; 

% Concatenate them into a 3D array 
d = cat(3, a, b, c); 

% Display the result 
disp('d(:,:,1) ='); 
disp(d(:,:,1)); 

disp('d(:,:,2) ='); 
disp(d(:,:,2)); 

disp('d(:,:,3) ='); 
disp(d(:,:,3)); 

Please refer to below documentation on the cat function for more clarity:

https://www.mathworks.com/help/matlab/ref/double.cat.html

Hope this helps!

[Stephen23]

"To merge multiple n-dimensional arrays of identical size into a single 3-dimensional array, the cat function in MATLAB can be utilized."

Not in general, CAT can't be utilized alone for this purpose. Here is a simple counter-example with three "n-dimensional arrays of identical size" and the output is definitely not a "single 3-dimensional array":

a = rand(5,4,3,2);
b = rand(5,4,3,2);
c = rand(5,4,3,2);
d = cat(3,a,b,c);
size(d) % not a "3-dimensional array"

ans = 1×4

5 4 9 2

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