MATLAB: Please help to vectorize this code.

for loopoptimize codepre-allocatevectorized

    tic;
    load 'CCA_result.mat';
    CleanData1= CleanData1';
    rows = size(CleanData1);
    Result_cpei = zeros(1,rows(1)); 
    for N = 1:1:rows
        tmp=CPEI(CleanData1(N,:),0);
        Result_cpei = [Result_cpei tmp];
        save ('CPEI','Result_cpei');
    end
The output is not a matter since I got the right output. The issue is can this code to be vectorized?

Best Answer

Start with avoiding to re-create the formerly pre-allocated output and do not overwrite the output file in each iteration:
   Data = load('CCA_result.mat');  % Avoid dynamic creation of variables
   CleanData1 = Data.CleanData1';
   rows = size(CleanData1, 1);   % Guessed, perhaps you want NUMEL or the 2nd dim
   Result_cpei = zeros(1, rows); % Pre-allocation
   for N = 1:rows
     Result_cpei(N) = CPEI(CleanData1(N,:),0);  % Write ionto pre-allocated array
   end
   save('CPEI.mat', 'Result_cpei');
If this can be vectorized depends on the contents of the function CPEI. If this function accepts a array as input, the code can be simplified to:
   Data = load('CCA_result.mat');
   CleanData1 = Data.CleanData1';
   Result_cpei = CPEI(CleanData1,0);
   save('CPEI.mat', 'Result_cpei');
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