Re: Bode function only run once

[Marco Atzeri]

Am 07.02.2020 um 14:27 schrieb Nick7:
> Hello
> I am running the following script:
>   
>
> pkg load control;
> clear global;
> s = tf('s');
> tf = 1/(1+s*0.318e-8);
> bode(tf);
>
>
> The first run time the Bode plots appears well. When I try to rerun the
> script the following error appears:
>
> > > Bode
>
> error: freqresp: second argument 'w' must be a real-valued vector of
> frequencies
> error: called from
>      freqresp at line 52 column 5
>      subsref at line 39 column 13
>      Bode at line 3 column 3
> > >
>
> Any help please?
>
> Regards
>   Nick

you are redefinining the meaning of tf on your second assignment.
Try using a different name

octave:18> s = tf('s');
octave:19> tfs = 1/(1+s*0.318e-8);
octave:20> bode(tfs);
octave:21> s = tf('s');
octave:22> tfs = 1/(1+s*0.318e-8);
octave:23> bode(tfs);