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Topic: matrix mean
Replies: 9   Last Post: Sep 11, 2013 5:13 PM

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 Puneet Posts: 14 Registered: 8/12/13
Re: matrix mean
Posted: Sep 10, 2013 5:41 AM

dpb <none@non.net> wrote in message <l0lbpf\$lel\$1@speranza.aioe.org>...
> On 9/9/2013 6:40 AM, Puneet wrote:
> > Hi - this is begginers question.
> > I have a data set - 16 rows and 16 columns - I would like to average
> > every 2 points to get an 8 rows 8 columns matrix.
> >
> > This is a learning phase so I can run something similar later for larger
> > data sets.
> > Thanks.

>
> One way...(not necessarily the best :) ) presuming that the "every 2
> points" means in both directions given the resulting size of output for
> the described input. Similar works w/ filter() for the vector case.
>
> m4=filter2(ones(2)/4,z);
> m4=m4(1:2:end,1:2:end);
>
> Hint: look up 2D convolution... :)
>
> accumarray() could be you friend amongst other ways to attack it...
>
> --

i would like to rephrase my query. if i have a row vector of length 16 and i want to average every 2 consecutive elements and save it as a row vector, then how should i go about it. i know its a beginner query but may be its too specific as a really couldn't find it any where or even close to it.

Date Subject Author
9/9/13 Puneet
9/9/13 Curious
9/9/13 Curious
9/9/13 dpb
9/10/13 Puneet
9/10/13 Curious
9/10/13 dpb
9/10/13 dpb
9/10/13 Steven Lord
9/11/13 arich82