How to process a large matrix of size 28x28x11684?

I'm having 11684 matrices each of size 28x28. So the variable a has size 28x28x11684. Now i would like to do sorting them using a for loop on each matrix of 28x28 and store it in a variable z. Here is my code

for i=1:11684
    z=sort(a(:,:,i));
end

When i run the code, it is giving me the variable z of size 28x28. But i want the variable z to be of size 28x28x11684. Plese help me.

Answer 1

[Andrei Bobrov]

Just:

z = sort(a);

With loop:

k = size(a,3);
z = a;
for ii = 1:k
    z(:,:,ii) = sort(a(:,:,ii));
end

[Ajay Ganti]

thank you