Re: Vectors
- To: mathgroup at smc.vnet.net
- Subject: [mg13917] Re: [mg13894] Vectors
- From: "Jens-Peer Kuska" <kuska at linmpi.mpg.de>
- Date: Mon, 7 Sep 1998 01:22:42 -0400
- Sender: owner-wri-mathgroup at wolfram.com
Hi,
vec={a,b,c}
and
Cross[vec,vec]
works correct, and gives 0!
Or did You type "(a b c)" ?
If Your answer is "Yes" You shoud
take three weeks to read "The Book"
about Mathematica.
Hope that helps
Jens
-----Original Message-----
From: Olivier Georg <ogeorg at imtsg12.epfl.ch> To: mathgroup at smc.vnet.net
Subject: [mg13917] [mg13894] Vectors
>Hi,
>
>I want to do symbolic calculation with vectors, in particular, I want to
>do a vector product. But if I declare:
>
> A = (a b c)
>
>and do
>
> A x A
>
>(which should give zero), but instead I get:
>
> Cross::"nonn1": "Not all of the arguments are vectors
> of required length
>
>since there's no way for mathematica to know that a, b and c represent
>numerical value and not functions or lists. Is there a way around to
>perform this kind of calculation ?
>
>Please e-mail also, thanks,
>
>Olivier
>--
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