MATLAB: How to do this calculation not by ‘for’ cycle

for loop; data;

I have the below data:
data =[...
  1.0000    1.0000    1.0000   53.1100;...
  1.0000    2.0000    2.0000   59.0900;...
  2.0000    1.0000    2.0000   71.3100;...
  2.0000    2.0000    1.0000   70.2400]
Now I want to get a 'variable'–Data as below:
Data=[53.11+59.09  53.11+71.31  53.11+70.24;
      71.31+70.24  59.09+70.24  59.09+71.31]
I can get 'Data' by 'for' cycle function but I want to do this work by other better method.
The addition logic is that:
take column 2 of data for example, both data(1,2) and data(3,2) equal 1.0000, so add data(1,4) and data(3,4) to get Data(1,2).

Best Answer

One possible way to do it:
data = [1    1    1   53.1100
        1    2    2   59.0900
        2    1    2   71.3100
        2    2    1   70.2400];
%first split data into two matrices for easier referencing:
rowdest = data(:, 1:end-1);
rowvals = data(:, end);
%second create matrix of column indices
coldest = repmat(1:size(rowdest, 2), size(rowdest, 1), 1);
%third use accumarray to compute the sum:
newdata = accumarray([rowdest(:) coldest(:)], repmat(rowvals, size(rowdest, 2), 1))
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