[Scilab-Dev] Problems with function roots

[Serge Steer]

Le 17/07/2010 23:28, Pedro Ledoux a écrit :
>
> Hello
>
> I'm Pedro Ledoux, I'm a electrical engineering student. At university
> I try to do as many as possible using free softwares including Scilab.
> During the project of a passive high pass filter  I had to get the
> roots of a 12 order polynomial function. So I typed in Scilab environment:
>
>  v= [1.12119799 0 3.512D+13 32 3.275D+27 0 1.117D+41 4.952D+27
> 1.722D+54 0 1.224D+67 0 3.262D+79 ];
> roots(v)
>
> Unfortunately Scilab failed. The message :" !--error 24 Convergence
> problems,," has appear. I didn't tryed it in Matlab but GNU octave was
> able to calculate those roots. By now I'm not a great programmer yet
> and the only way that I have to contribute to Scilab is using in and
> reporting bugs.
>
> If almost developers are French I can speak French also if it is more
> comfortable.
>
>
>   
You can use roots(v,"e"). In this the algorithm computes the eigenvalues
of the companion matrix. It is a slower algorithm, but it never fail.

Serge Steer

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