Remove close value for matrix

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Laura
Laura on 11 Jul 2013
I have a matrix A with has dimension n x3
I want to remove the data values that are so close to certain value or repeated.
Let say A = [ 1 1 1; 1 1 1.5; 1.1 1.2 1 , so on ]
definitely they are closed and I cant use "unique" command because they are not repeated for all 3 values.
How to remove those value in certain distance: let say if the distance is less than or equal to .5, then remove that row. We can average those value that would be awesome all close value and replace it in the new matrix.
Note: A has unknown row, so it has to be a loop.

Accepted Answer

Azzi Abdelmalek
Azzi Abdelmalek on 11 Jul 2013
Edited: Azzi Abdelmalek on 11 Jul 2013
A = [ 1 1 1; 1 1 1.5; 1.1 1.2 1 ;2 3 4;2.1 2.9 4.5]
tol=0.5*ones(1,size(A,2));
v=(1:size(A,1));
idx=arrayfun(@(x) all(bsxfun(@le,abs(bsxfun(@minus,A,A(x,:))),tol),2),v,'un',0);
idx=cell2mat(idx);
for k=1:size(idx,1)
q=idx(:,k);
A(q,:)=repmat(mean(A(q,:)),sum(q),1);
end
out=unique(A,'rows')

More Answers (1)

Matt J
Matt J on 11 Jul 2013
Edited: Matt J on 11 Jul 2013
This one seems to be pretty popular
I'm sure you could browse the FEX for still more clustering algorithms.

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