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

 Messages: [ Previous | Next ]
 Curious Posts: 2,359 Registered: 12/6/04
Re: matrix mean
Posted: Sep 10, 2013 6:49 AM

"Puneet" wrote in message <l0mpfl\$mjr\$1@newscl01ah.mathworks.com>...
> 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.

doc filter

% The Examples section shows you how to do almost EXACTLY
% what you want (just change windowSize from 5 to 2).

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