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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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Justin

Posts: 7
Registered: 2/23/09
Re: second largest element in a matrix
Posted: Mar 4, 2009 5:24 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

one straight forward method is to build a length L sorted list, and for each element in te matrix, insert it into the list which cost logL, and discard the smallest element. Totally this cost nlogL. I am also looking for a simple function that finds the second largest element..... don't know if matlab has one



Walter Roberson <roberson@hushmail.com> wrote in message <STjCk.14881$Il.4473@newsfe09.iad>...
> Oluwa KuIse wrote:
>

> > Can anyone pls tell me how I can find the second (or third) largest element in a
> > matrix AND its position.

>
> The algorithms that people gave all ran in -at least- time N (length of the
> matrix) times the number of largest elements to be found.
>
> I was interested to discover a couple of weeks ago that there are simple
> algorithms that for any fixed number L of largest elements, are able to
> execute a -single- pass over the array and using L (or was it L+1 ?)
> temporary storage locations, find the L largest values.
>
> Unfortunately in the short time I put into reading the algorithm, I did
> not understand how the algorithm worked, so I cannot describe it here.
> And I no longer recall where I found the algorithm -- though either as
> a reference here or on wikipedia are the two most likely candidates.



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

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