How to find the Nth largest value in array? Even with duplicate values?

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If i wanted to know what the the 2nd, 3rd, 4th whatever largest value was in my array, how would i do that? I thought at first just sort the array and then get the array(N) value but if you have duplicates it doesnt work like that.

Answers (1)

Image Analyst
Image Analyst on 6 Nov 2020
Why doesn't it work? Works for me.
v = [1,2,3,4,5,5,5,5,44,55,123,456]
% Sort array in decreasing order.
sorted_v = sort(v, 'descend')
% Take the 7'th largest one. Should be 5:
N = 7;
result = sorted_v(N)
It shows
v =
1 2 3 4 5 5 5 5 44 55 123 456
sorted_v =
456 123 55 44 5 5 5 5 4 3 2 1
result =
5
If it doesn't work for you, give your vector and N and the desired output.
  2 Comments
Image Analyst
Image Analyst on 6 Nov 2020
Yes, I thought of that. But that's not the Nth largest value. It's the Nth largest of the unique values, which in this case (N=7) is the 10th largest value, not the 7th. But since he blew past the posting guidelines and posted it without an example, you may be right. He only said the desired output was 33 but didn't give the original vector. He only said that it "doesn't work" which might mean any number of things from a syntax error to not giving the desired values. Well, we've now given it both ways so hopefully one of those will work for Jared.

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