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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