Re: Vectors
- To: mathgroup at smc.vnet.net
- Subject: [mg13914] Re: Vectors
- From: "Allan Hayes" <hay at haystack.demon.cc.uk>
- Date: Mon, 7 Sep 1998 01:22:40 -0400
- References: <6ssuku$m7j@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Olivier:
Do you mean
A = {a,b,c};
?
This gives
Cross [A,A]
{0,0,0}
Allan
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Allan Hayes
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Olivier Georg wrote in message <6ssuku$m7j at smc.vnet.net>...
>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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