How to find a spesific row value and write it in to a matrix?

Hello all,I have a matrix A(25,3,4) and in the third column I want to show the index of third dimension value. For example for the first dimension: val(:,:,1) 2 5 _ 3 4 _ . . . and inside of it there are 25 integer numbers,and ı want to add "1" to the third column that i mentioned with _ because of the third dimensions number Or for a value inside of the second dimension val(:,:,2) 3 5 _ 2 4 _ . . .

Then ı want it to write the third column "2" that comes from the dimension number. Is it possibile to write it? I hope my question is clear. Thank you

[Bob Thompson]

This is very easy to do with indexing. There might be a fancier way than what I am about to suggest, but I would think to use a loop first.

for k = 1:size(A,3);
 A(:,3,k) = k;
end

I think that will produce the result you're looking for, but if not then please feel free to explain more.