Re: Trouble installing control toolbox

[Alexander Hansen]

On 12/13/12 5:21 PM, Michael Noone wrote:
> Thanks Alexander - it looks like I don't have tf2sys. Maybe that's been
> made antiquated? Either way, I tired another route, and got yet another
> error message! Any ideas on the below error? This isn't going well for
> me! :)
> 
> octave:2> pkg load control
> octave:3> pkg describe control
> ---
> Package name:
>         control
> Version:
>         2.3.52
> Short description:
>         Octave control systems package based on the proven SLICOT library
> Status:
>         Loaded
> octave:4> A = tf(1, [1 2 3])
> 
> Transfer function 'A' from input 'u1' to output ...
> 
>             1
>  y1:  -------------
>       s^2 + 2 s + 3
> 
> Continuous-time model.
> octave:5> bode(A)
> error: popen2: popen2 (child): unable to start process -- No such file
> or directory
> error: called from:
> error:  
> /usr/share/octave/3.6.2/m/plot/private/__gnuplot_open_stream__.m at line
> 30, column 44
> error:   /usr/share/octave/3.6.2/m/plot/__gnuplot_drawnow__.m at line
> 72, column 19
> /bin/sh: gnuplot: command not found
> error: `unset' undefined near line 6 column 1
> warning: broken pipe -- some output may be lost
> 
> 

Looks like you either need to install gnuplot or use

        graphics_toolkit ('fltk')

to switch to the built-in fltk graphics.
-- 
Alex