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How to remove duplicate rows from .mat file or text file with out sorting?

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Ram
Ram on 1 Jul 2018
Edited: jonas on 1 Jul 2018
Hello all, I have 64954930*3 matrix. There are duplicate rows are exist. How can i delete with out sorting of original matrix.
This is my code
load('myfile.mat');
%A = unique(myfile(:,:),'rows');
A = myfile(:,:);
% B = unique(A,'stable');
% save('B.mat','B');
%C = setxor(A,'rows','stable');
should i write forloop? i used different formats. but getting various errors. such as sort input arguments of struct; Undefined myfile. Kindly help me. Thanks in advance.
  7 Comments
jonas
jonas on 1 Jul 2018
Nothing is going to work for you if you get the message:
Undefined function or variable 'A'.
becuause it means there is no variable called A...

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Accepted Answer

jonas
jonas on 1 Jul 2018
Seems you are really close to finding the solution.
out=unique(A,'rows','stable')
should give you the unsorted unique rows :)
  14 Comments
jonas
jonas on 1 Jul 2018
As Paolo previously said, you are working with floating point numbers. That is why you need to use uniquetol and not unique. You need to define what a duplicate is (by setting a tolerance). If you set the tolerance to zero, then you will probably end up with the same result using both functions. However, are 1.0000000 and 1.00000001 duplicates? That's what you define with tolerance, i.e. the max difference between two numbers for them to be defined as same number.
Or simply put. Do you still have duplicates after you use unique? Then you need to use uniquetol to remove rows that are almost identical to other rows.

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