Remove duplicate rows from matrix

Hello

I have a 2xN matrix where each column represent the x and y coordinates of a 2D point. I need to remove any duplicate point from this matrix, any suggestions?

Best regards MC

[Stephen23]

Note that 2xN is a matrix, and not a vector.

[MC]

My bad, I meant a matrix:)

[Garvit Amipara]

It would be very nice of you, if you could change the title of this question, it misleads others who are actually looking for the answers related to 'vector'. Thank you(:

[Stephen23]

@Garvit Amipara: done.

Answer 1

[Stephen23]

It is trivial to use unique to get only the unique rows of matrix. Because your matrix is arranged 2xN, simply transpose before and after:

unique(M.','rows').'

[MC]

Thanks this worked almost! I manually checked the matrix, there is one part where there is 4 equal points, the command unique removes only two of them.

I just run it twice and it works fine!

[Mr M.]

what does it mean .' ? why not just ' is the transpose?

[Guillaume]

@Mr M, Why don't you look it up in the doc.

' is the conjugate transpose.

.' is the non-conjugate transpose.

If your matrix is made of only non-complex number the difference does not matter, but if you may have complex numbers in your matrix, using ' instead of .' will lead to problems.

Stephen is correct to use .' in his answer.

[LO]

how can I keep all values of each row ?

[Paween Pongsomboon]

I don't know if you still alive, stephen. I wish I could hug you now!

Thx for the super solution