[scilab-Users] what am I doing wrong

[A. Ismael F. Vaz]

Hi,

This is better explained by using precedencies in mathematical expressions.
First we solve what's in parenthesis, then potentiation, then multiplication
and division, and in the end the summation and subtractions from left to
right.

In -10^2 the potentiation has priority over the subtraction.

In (-10)^2 the parenthesis has priority over the potentiation.

You obtain exactly the same behavior using a scientific calculator, in fact
I warn my students about this when I taught Numerical Methods.

Best regards,
Ismael

-----Mensagem original-----
De: Carrico, Paul [mailto:paul.carrico at esterline.com] 
Enviada: quarta-feira, 14 de Setembro de 2011 14:28
Para: users at lists.scilab.org
Assunto: RE: [scilab-Users] what am I doing wrong

Well

Imagine you're computing a function such as : f = x(1)^2 - x(2)^2 ... The
negative sign is not influence by the square, isn't it ?

Be rigorous in using parentheses ....

Paul


-----Message d'origine-----
De : Maso RICCI [mailto:ricci2 at unisi.it] Envoyé : mercredi 14 septembre 2011
15:25 À : users at lists.scilab.org Objet : Re: [scilab-Users] what am I doing
wrong

got it ...

thanks for helping me

but is it not a little confusing ?

/maso

Il 14/09/2011 15.20, Carrico, Paul ha scritto:
> Try (-10)^2
>
> Different from -1*10^2 == -1*(10)^2
>
> Paul
>
>
> Please consider the environment before printing this e-mail
>
>
> -----Message d'origine-----
> De : Maso RICCI [mailto:ricci2 at unisi.it] Envoyé : mercredi 14 
> septembre 2011 15:18 À : users at lists.scilab.org Objet : [scilab-Users] 
> what am I doing wrong
>
> Ehm... pretty sure I am going to place a dummy question
>
> but I got to do it:
>
> is it corret the below result from my scilab console ?
>
> -->-10^2
>    ans  =
>
>     - 100.
>
> thanks
>
> /maso
>

--
----------------------------------------
Maso RICCI PhD
Dipartimento Farmaco Chimico Tecnologico Università degli Studi di Siena Via
Aldo Moro,2 Siena

phone: +390577234367
email: ricci2 at unisi.it
----------------------------------------

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