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Finding Unique values for First Row of a Matrix

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MShia on 24 Dec 2019
Edited: MShia on 24 Dec 2019
I have a matrix which I intend to use, such that, I have to keep the uniqe elements of the first row in a specific manner, Following is to describe the process in a bit detail:
We scan the first row and keep it as such if all the elements are unique. Otherwise for a repeating value we select the next value which is uique. For example for the following matrix A:
The output should be Output = [5 6 7 9 11], where first element A(1,1) is kept as such, since the the next element in the first row i.e. A(1,2) = A(1,1), we choose next unique element in this column i.e. A(2,2) , And So on to scan the entire first row without repetition. This way to achieve the desired output for generalized matrix ... Any input will be appreciated .


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MShia on 24 Dec 2019
Please assume that its not the case, we will always find unique entries(may be I couldnt reflect that in the example matrix)
Walter Roberson
Walter Roberson on 24 Dec 2019
ismember() the current column against the list of values already used. The first item not present is the one to output and add to the list of values used.

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Accepted Answer

Andrei Bobrov
Andrei Bobrov on 24 Dec 2019
Let A - your array.
output = A(1,:);
for i = 2:numel(output)
u = unique([output(1:i-1)';A(:,i)]);
output(i) = u(i);

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MShia on 24 Dec 2019
Thanks Sir very elegant solution! The only modification I had to do, was to use the unique command with "stable" option to maintain the sequence. I really appreciate it .

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