How to remove rows having repeating elements from a matrix?
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If I have a matrix A=[ 1 2 1 4; 1 2 3 4; 3 2 1 4; 3 3 2 1] then I want a matrix as B=[ 1 2 3 4; 3 2 1 4] so that both the 1st and 4th row will be deleted as they have repeated elements. pls help me to find out the code.
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Accepted Answer
  Roger Stafford
      
      
 on 25 Apr 2016
        
      Edited: Roger Stafford
      
      
 on 27 Apr 2016
  
         t = false(1,size(A,1));
   for k = 1:size(A,1)
     u = unique(A(k,:));
     t(k) = size(u,2)==size(A,2);
   end
   B = A(t,:);  % Rows with repeated elements deleted
More Answers (1)
  Baltam
      
 on 25 Apr 2016
        The below method is not elegant but it works.
   A=[ 1 2 1 4; 1 2 3 4; 3 2 1 4; 3 3 2 1];
   index = zeros(1,size(A,1));
   for i = 1:size(A,1)
       if numel(unique(A(i,:))) ==  numel(A(i,:))
          index(i)=1;
       end
   end
   index = logical(index);
   B = A(index,:);
Kind regards,
Baltam
2 Comments
  David Wagener
 on 1 Dec 2019
				The second version shown here while not as elegant works better if you have a large matrix and are using parallel processing.  I'm not an expert by any means but the second version did not overload my machine like the first one did.
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