How to use Uniquetol without sorting?

Hello everyone,

I'm using the function "Uniquetol" to remove the duplicate vector from a matrix A which the size is (3, 10).

B  =  ( uniquetol(A', 1e-6, 'ByRows', 1) )'; 

It works very well, but it is also sorting my matrix which what I don't want

Please, can anyone tell how can we use the function "Uniquetol" without sorting ?

Answer 1

[Guillaume]

[~, colindices] = uniquetol(A', 1e-6, 'ByRows', true);   %get indices of unique value. Is sorted BY VALUE
B = A(:, sort(colindices))   %Use the indices sorted BY INDEX instead

[AMEHRI WALID]

Great, it's working like a charm !

Thank you :)

[Quang Huy Pham]

I encountered the same problem and I tried your solution but it didn't work for me. For example, let

A=[0.71 -0.71 -0.69 0.69]

Then I tried

 [~, idx] = uniquetol(A,0.1);
 A(sort(idx))

But it returned [-0.71 0.69] instead of [0.71 -0.71].

[Bruno Luong]

Both solutions are equally valid. They respect the order in the original matrix.

Sorry Huy, there is not reason your solution is right and other is wrong.

[Min Zhang]

Try this:

A = [0.05 0.11 0.18; ...

0.46 0.52 0.76;...

0.34 0.36 0.41; ...

0.18 0.21 0.29; ...

0.46 0.52 0.76;...

0.05 0.11 0.18;];

%

[~, colindices] = uniquetol(A, 'ByRows', true)

sort(colindices)

% get indices of unique value. Is sorted BY VALUE

B = A(sort(colindices),:)