MATLAB: Insert Zeros in every n-rows at the regular interval in 3rd dimension for an existing 3D Matrix.

incertrows

I have a m*n*t matrix. In 3rd dimension t, I want to insert m*n zeros at a particular interval. For example input
 A(:,:,1) =
     9     8    -8    -3
    -3    -3     7     8
    -3   -10    -1     8
    10     5   -10   -10
     4     7    11    13
A(:,:,2) =
    14     9     7     5
     3     5     2    11
    15    12    15     8
     7    10     9     5
    14     4    15    13
A(:,:,3) =
    14    17    17    15
    13    21    21    19
    15    21    17    17
    14    21    18    13
    17    16    13    17
A(:,:,4) =
    14    21    15    19
    15    12    20    11
    15     5     4     9
     7     6    15    16
     3     2    17    10
result would be:
 A(:,:,1) =
     9     8    -8    -3
    -3    -3     7     8
    -3   -10    -1     8
    10     5   -10   -10
     4     7    11    13
A(:,:,2) =
    14     9     7     5
     3     5     2    11
    15    12    15     8
     7    10     9     5
    14     4    15    13
A(:,:,3) =
     0     0     0     0
     0     0     0     0
     0     0     0     0
     0     0     0     0
     0     0     0     0
A(:,:,4) =
     0     0     0     0
     0     0     0     0
     0     0     0     0
     0     0     0     0
     0     0     0     0
A(:,:,5) =
    14    17    17    15
    13    21    21    19
    15    21    17    17
    14    21    18    13
    17    16    13    17
A(:,:,6) =
    14    21    15    19
    15    12    20    11
    15     5     4     9
     7     6    15    16
     3     2    17    10
A(:,:,7) =
     0     0     0     0
     0     0     0     0
     0     0     0     0
     0     0     0     0
     0     0     0     0
A(:,:,8) =
     0     0     0     0
     0     0     0     0
     0     0     0     0
     0     0     0     0
     0     0     0     0
Thanks!

Best Answer

Assuming every page really is m x n (cf. Stephen's comment),
   A=rand(3,4,6); %fake data
pattern=[1 1 1 0 0];  %insert zero every 4th and 5th page
[m,n,t]=size(A);
q=floor(t/nnz(pattern));
idx=repmat( reshape(pattern,1,1,[]) , 1,1,q)& true(m,n);
out=zeros(size(idx));
out(idx)=A(1:nnz(idx)),
results in
out(:,:,1) =
      0.8147    0.9134    0.2785    0.9649
      0.9058    0.6324    0.5469    0.1576
      0.1270    0.0975    0.9575    0.9706
out(:,:,2) =
      0.9572    0.1419    0.7922    0.0357
      0.4854    0.4218    0.9595    0.8491
      0.8003    0.9157    0.6557    0.9340
out(:,:,3) =
      0.6787    0.3922    0.7060    0.0462
      0.7577    0.6555    0.0318    0.0971
      0.7431    0.1712    0.2769    0.8235
out(:,:,4) =
       0     0     0     0
       0     0     0     0
       0     0     0     0
out(:,:,5) =
       0     0     0     0
       0     0     0     0
       0     0     0     0
out(:,:,6) =
      0.6948    0.0344    0.7655    0.4898
      0.3171    0.4387    0.7952    0.4456
      0.9502    0.3816    0.1869    0.6463
out(:,:,7) =
      0.7094    0.6797    0.1190    0.3404
      0.7547    0.6551    0.4984    0.5853
      0.2760    0.1626    0.9597    0.2238
out(:,:,8) =
      0.7513    0.6991    0.5472    0.2575
      0.2551    0.8909    0.1386    0.8407
      0.5060    0.9593    0.1493    0.2543
out(:,:,9) =
       0     0     0     0
       0     0     0     0
       0     0     0     0
out(:,:,10) =
       0     0     0     0
       0     0     0     0
       0     0     0     0
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