MATLAB: Improve the code’s time of execution. I want to avoid the for loops and use element by element calculations. Do you guys have something in mind?? Thank you in advance.

reduction of execution time

for i=1:v
    for j=1:v
        for k=1:m
            if dm==k && j<=n && A~=j
                ddii=((design(i,k)-design(j,k))^2);
                summ=summ+ddii; 
            elseif dm~=k && j<=n && A~=j 
                ddii=((design(A,k)-design(j,k))^2);
                summ=summ+ddii;                                  
            end
            k=k+1;j=j;i=i;
        end
        ddcc(j,i,:)=[j i summ];
        j=j+1; i=i; k=1;summ=0;
    end
    cc(i,:)=min(nonzeros(ddcc(:,i,3))); 
    i=i+1;j=1;k=1;
end

Best Answer

See if the following produces correct output, first; should reduce the time slightly by eliminating redundant tests and shortening the loop on j. Whether it's significant will depend how many cases get missed so is data-dependent.
for i=1:v
  for j=1:n
    if j==A, continue, end
    for k=1:n
      if k==dm 
        ddii=((design(i,k)-design(j,k))^2);
        summ=summ+ddii; 
      else
        ddii=((design(A,k)-design(j,k))^2);
        summ=summ+ddii;                                  
      end
    end
    ddcc(j,i,:)=[j i summ];
    summ=0;
  end
  cc(i,:)=min(nonzeros(ddcc(:,i,3))); 
end
After that, you're walking thru the arrays in the opposite storage as to sequential addressing; whether this is a major issue has to do with stride and cache size, etc., but might try using
design=design.';
before beginning the loop and see if it makes any difference in speed when the first index gets incremented sequentially in the innermost loop.
After that, I'd have to think more than I wish to expend on a Sunday afternoon to see if could do better on the actual computation altho it would seem with some consideration a logical addressing expression and pdist|pdist2 should be able to help.
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