MATLAB: Check if subsequent elements in a 3D matrix are the same value

3d matrixcountdiff()sum

Hello,
I have a 121x97x51135 matrix of 1's and 0's which flag certain periods of time. I would like to produce new variables that count the number of times a 1 is followed by another in the subsequent element, and another if two ones follow in the subsequent 2 elements.
For instance:
if
A(:,:,1) = ones(3,3,1);
A(:,:,2) = ones(3,3,1);
A(:,:,3) = zeros(3,3,1);
A(:,:,4) = ones(3,3,1);
The output variable for the first test (1 followed by 1) would be a 3×3 matrix with a count of the number of times that occurred in A and thus result = ones(3,3).
Any suggestions how to do this with out a loop? Not sure if a function out there works for this. I tried diff() but diff won't work in terms of adding up these times. For instance:
diff(A,[],3)
ans(:,:,1) =
       0     0     0
       0     0     0
       0     0     0
ans(:,:,2) =
      -1    -1    -1
      -1    -1    -1
      -1    -1    -1
ans(:,:,3) =
       1     1     1
       1     1     1
       1     1     1
Thanks in advance!

Best Answer

>> Y2 = X(:,:,1:end-1) & X(:,:,2:end);
>> Y3 = X(:,:,1:end-2) & X(:,:,2:end-1) & X(:,:,3:end);
>> sum(Y2,3) % two consecutive "ones"
ans =
     1   1   1
     1   1   1
     1   1   1
>> sum(Y3,3) % three consecutive "ones"
ans =
     0   0   0
     0   0   0
     0   0   0
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