[Scilab-users] 'fsolver'

[Dang Ngoc Chan, Christophe]

Of course, read "guess" instead of "guest" (-:

--
Christophe Dang Ngoc Chan
Mechanical calculation engineer


-----Message d'origine-----
De : Dang Ngoc Chan, Christophe
Envoyé : mercredi 27 janvier 2016 16:00
À : 'Users mailing list for Scilab' <users at lists.scilab.org>
Objet : RE: [Scilab-users] 'fsolver'

Hello,

> De : fujimoto2005
> Envoyé : mercredi 27 janvier 2016 15:24
>
> if f(x)=0 has multiple solutions and I want to get the  smallest solution, is there any way to get a such solution by 'fsolver'?
> In my actual problem, 'fsolver' give the largest solution.

I'm afraid the solution you get depends on the initial guest.
The help page says it uses the Powell hybrid method; I don't know it, but the Wikipedia page for the Powell method tells it finds a *local* minimum https://en.wikipedia.org/wiki/Powell%27s_method

So you probably have to seed with several initial guests (randomly or systematically) and select the smallest one (unless you have another method to get closer to the final solution).

HTH

--
Christophe Dang Ngoc Chan
Mechanical calculation engineer
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