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Re: simple (not for me) operation on matrix

 From: Quentin Spencer Subject: Re: simple (not for me) operation on matrix Date: Tue, 13 May 2003 09:29:05 +0200 User-agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.3) Gecko/20030430 Debian/1.3-5

```Here's a quick solution, but there may be a more efficient way that
avoids the FOR loop using something like 'reshape':

N = size(big_matrix,1);

for n = 1:N/2
new_matrix(n,:) = sum(big_matrix([n*2-1,n*2],:));
end

Paolo Ariano wrote:

```
```hi *

ive a big matrix (750 cols* 140 rows) for example:

1 2 3 2 4 5 6
3 4 6 5 3 2 1
2 4 5 6 7 8 8
6 7 5 4 3 2 1

i need to obtain a new matrix where i sum line 1 and line 2, then line 3
and line 4 and so on as:

(1+3) (2+4)
(2+6) (4+7)

i'm coming crazy for such a simple thing, any idea ?

thanks
paolo
```
```

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