Date: Nov 17, 2012 11:37 PM
Author: dpb
Subject: Re: Subtract values in a matrix
On 11/17/2012 1:45 PM, Bob Choy wrote:

> dpb <none@non.net> wrote in message <k88ofr$kd2$1@speranza.aioe.org>...

>> On 11/17/2012 1:12 PM, Bob Ferreira wrote:

>> ...

>>

>> > Example: m = [2,2,2;3,3,3;4,4,4] the matrix given should be

>> > [0,0,0;-1,-1,-1;-2,-2,-2]

>> >

>> > I hope I made myself understood, if not, please ask away.

>> ...

>>

>> No clue how you got the result from the description, sorry...

>>

>> What term, specifically was subtracted from which and how did you get

>> it to produce the desired result? (Actually, the answer to this may

>> well provide you w/ the (or at least a) solution).

...

> Okay well, the values in the second line of the matrix becomes the

> result of the first value of that column, minus the value that was there

> before, and after that, all values in the first line become all zeros.

>

> So in the example, m = [0,0,0;(2-3),(2-3),(2-3);(2-4),(2-4),(2-4)]

I still don't see how the column comes into and it's not clear to me

which matrix is "the" matrix, sorry...

I can get your answer via

>> n=repmat([m(1,:)],size(m,1),1);

>> n-m

ans =

0 0 0

-1 -1 -1

-2 -2 -2

>>

Whether that's actually the result you want or not, I've no klew...

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