Re: Functions with vector arguments
- To: mathgroup at smc.vnet.net
- Subject: [mg36218] Re: Functions with vector arguments
- From: Alexander Dreyer <dreyer at itwm.fhg.de>
- Date: Tue, 27 Aug 2002 02:07:26 -0400 (EDT)
- Organization: Fraunhofer ITWM
- References: <akcpm8$557$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
anhjunk wrote:
>
> Some functions with vector arguments work as expected and some give
> errors. I would appreciate if someone can clarify why.
>
> First an example of a function definition that works fine :
> f[u_,v_] := u.v
> Calling it with f[{x1,y1},{x2,y2}] gives the expected result x1 x2 +
> y1 y2.
>
> Now an example that does not work :
> g[u_,v_] := u-v
> Calling it with g[{x1,y1},{x2,y2}] one would expect the answer {x1-x2,
> y1-y2} but instead one gets error messages.
>
> Why ? And how do I fix g (i.e write a function that outputs the
> difference of 2 vectors).
>
> Thanks
Hello,
in fact this call works fine on my Mathematicas (3.0 up to 4.1). Did You
really use the minus character? Maybe some erroneous code was assigned
to g before. Restart Mathematica or use Remove[g] to really start up
from the beginning.
Sincerly
Alexander
--
/ Alexander Dreyer, Dipl.-Math. - Abteilung Adaptive Systeme \
/ Fraunhofer Institut fuer Techno- und Wirtschaftsmathematik (ITWM) \
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