Re: mathematica newbie question
- To: mathgroup at smc.vnet.net
- Subject: [mg66900] Re: mathematica newbie question
- From: albert <awnl at arcor.de>
- Date: Sat, 3 Jun 2006 03:25:26 -0400 (EDT)
- References: <e5osv8$i51$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Jeremy Watts wrote:
> Hi,
>
> Just trying to get to grips with Mathematica and matrices. Why is it when
> I enter :-
> {0, 0, 0}, {1, -1, -1}, {-1, 1, 1}}^2
>
> then Mathematica returns :-
>
> {{0, 0, 0}, {1, 1, 1}, {1, 1, 1}}
>
> and not {{0,0,0},{0,0,0},{0,0,0}} (the actual square of the matrix) as I'd
> have expected?
>
> Is it treating what I entered as separate vectors or something, and not
> an actual matrix?
Yes, what you want is Dot (.) not Power(*), and x^2 maps to x*x for matrices
also. This does what you want:
m = {0, 0, 0}, {1, -1, -1}, {-1, 1, 1}}
MatrixPower[x,2]
or:
m.m
hth,
albert