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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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 dpb Posts: 9,850 Registered: 6/7/07
Re: second largest element in a matrix
Posted: Nov 19, 2012 12:47 PM

On 11/7/2012 2:04 PM, sssbi2009@gmail.com wrote:
> On Friday, April 3, 2009 5:59:02 PM UTC-5, Paul wrote:
>> "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?

> if temp is your vector, you can get the second largest element as
> follows: [c,i] = max(temp(temp~=max(temp)))
>
> why would you sort it? this
> is the whole point of logical addressing in matlab.
>
> [c,i] = max(temp(temp~=max(temp)))
> I like your answer. Could you show me how to write like this to fine the third max? Thanks

max(x(x<max(x(x~=max(x))))) % throws away ties

After a while it starts to get messy trying to keep straight the nesting
levels... :)

And, at some number it would make sense to just go ahead and get the
order vector. I've not tried any timings to see how many values and
what size vectors is the breakpoint...

--

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