How to delete repeated rows without using unique function?

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I am looking for a way to delete repeated rows without using the unique function. For example if I have the matrix
A=[2 4 8; 8 2 4; 3 3 -6]
one of the first two rows needs to be deleted. Order doesn't need to be kept. I'm sure I need to use sort, and maybe find or diff. I'm not exactly sure how to go about it.
Any and all help is appreciated!
  4 Comments
Matt Kindig
Matt Kindig on 23 Apr 2013
It's strange that you consider the first two rows of A to be "repeated", since the order of the elements is different (one is a permutation of the other). Is this what you want?
Connor
Connor on 23 Apr 2013
They are considered repeated because order isn't important here. This is a very small part for my project, and isn't required. My professor said if we could do this we could get some extra credit. Thanks!

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Answers (1)

Matt J
Matt J on 23 Apr 2013
Edited: Matt J on 23 Apr 2013
Hint:
>> sortrows(sort(A,2))
ans =
-6 3 3
2 4 8
2 4 8
You should now find diff() rather helpful.
  2 Comments
Connor
Connor on 23 Apr 2013
I'm still kind of lost where I go from there. Using diff will give me the difference between each element in each row. So when there are three zeros, I know there is a duplicate row. How do I translate that into eliminating a row? I tried using find, but I'm not too familiar with the find function. Thanks for your help.
Cedric
Cedric on 23 Apr 2013
Lookup ALL and ANY in the doc; you could probably use them at some point, and be aware that ALL, ANY, DIFF, and many others operate along a dimension that you can specify.

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