MATLAB: Cut differently odd and even rows in matrix

MATLABmatrix manipulation

Hi, all!
I have a matrix like that:
a = [ 1     2     3     4     5     6     7     8;
      9    10    11    12    13    14    15    16;
     17    18    19    20    21    22    23    24;
     25    26    27    28    29    30    31    32];
I need to get this matrix:
 [ 3     4     5     6     7     8;
   9    10    11    12    13    14;
  19    20    21    22    23    24;
  25    26    27    28    29    30];
I want to cut first two values in odd lines and cut last two values in even lines. I means that I need something like this:
a = a(3:8, 1:2:end) && a(1:6, 2:2:end)
But it is incorrect. How can I do it correctly?

Best Answer

n = size(a, 2); % number of columns

a(1:2:n,:) = a(1:2:n,[[3:n],[1:2]]); % move first 2 elements in odd rows to the end

a = a(:, 1:n-2); % get rid of last 2 columns

Of course prettier to use circshift:
n = size(a, 2); % number of columns
a(1:2:n,:) = circshift(a(1:2:n,:),-2,2); % move first 2 elements in odd rows to the end
a = a(:, 1:n-2); % get rid of last 2 columns
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