Re: Transpose[A]*A wrong?
- To: mathgroup at smc.vnet.net
- Subject: [mg41151] Re: Transpose[A]*A wrong?
- From: bobhanlon at aol.com (Bob Hanlon)
- Date: Tue, 6 May 2003 05:55:51 -0400 (EDT)
- References: <b950vl$r49$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Presumably you want the Dot product
Transpose[A].A
Bob Hanlon
In article <b950vl$r49$1 at smc.vnet.net>, "Daniel Lidström"
<daniel.lidstrom at _DELETE_home.se> wrote:
<< Subject: Transpose[A]*A wrong?
From: "Daniel Lidström" <daniel.lidstrom at _DELETE_home.se>
To: mathgroup at smc.vnet.net
Date: Mon, 5 May 2003 06:39:49 +0000 (UTC)
Hi,
why does Mathematica give the wrong result here?
In[1]:= \!\(A\ = \ {{x\_11, x\_12, x\_13}, {x\_21, x\_22, x\_23}, {x\_31,
x\_32,
x\_33}}\)
Out[1]= {{x , x , x }, {x , x , x }, {x , x , x }}
11 12 13 21 22 23 31 32 33
In[2]:= Transpose[A]*A
2 2
2
Out[2]= {{x , x x , x x }, {x x , x , x x }, {x x , x x
, x }}
11 12 21 13 31 12 21 22 23 32 13 31 23
32 33
Look at the diagonal elements for example. >><BR><BR>