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Topic: second largest element in a matrix
Replies: 32   Last Post: May 5, 2013 10:31 AM

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 stephanie Posts: 1 Registered: 9/19/08
Re: second largest element in a matrix
Posted: Sep 19, 2008 12:39 AM

"Oluwa KuIse" <wespeakforex@yahoo.com> wrote in message <gav3p9\$som\$1@fred.mathworks.com>...
> Hello,
> Can anyone pls tell me how I can find the second (or third) largest element in a matrix AND its position. The max function gives the largest element and its position but how do I find the second largest element and its position?

There are 2 rudimentary ways that I can think of off the top of my head...none of them are optimal though..

1. Use max to find the largest element, then set this element to -Inf. Then use max again to find the 'next'(ie, second) largest element and its position.

This method is definitely only a quick heck, and not suitable for looking for the Nth largest element in case N in large.

2. Sort the matrix, then you will know the value of the second largest element, then use 'find' to get the position of this element.

Hope this helps,
stephanie

Date Subject Author
9/18/08 Oluwa KuIse
9/19/08 stephanie
9/19/08 Steven Lord
9/19/08 Oluwa KuIse
9/19/08 Pekka
9/19/08 Oluwa KuIse
9/21/08 Greg Heath
9/24/08 Walter Roberson
3/4/09 Justin
4/6/09 Bruno Luong
4/6/09 Jos
4/6/09 Bruno Luong
4/6/09 Bruno Luong
4/6/09 mike zander
4/7/09 Bruno Luong
4/7/09 Bruno Luong
4/3/09 Paul
11/7/12 sssbi2009@gmail.com
11/19/12 dpb
4/3/09 Paul
4/3/09 mike zander
4/3/09 mike zander
4/3/09 mike zander
4/3/09 Walter Roberson
4/3/09 mike zander
5/4/13 tilindg1@gmail.com
5/4/13 Nasser Abbasi
5/4/13 dpb
5/5/13 Nasser Abbasi
5/5/13 dpb
5/5/13 Bruno Luong
5/5/13 Nasser Abbasi
5/5/13 Bruno Luong