Re: Trouble installing control toolbox

[Michael Noone]

Hi Ben - this is what happens when I try that. Any ideas?

warning: X11 DISPLAY environment variable not set
pkg octave:1> pkg load control
octave:2> 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:3> graphics_toolkit gnuplot
octave:4> setenv GNUTERM windows
octave:5> bode(A)
Unknown or ambiguous terminal name 'windows'

gnuplot> set terminal windows enhanced title "Figure 1"
                      ^
         line 0: unknown or ambiguous terminal type; type just 'set terminal' for a list

On Thu, Dec 13, 2012 at 8:09 PM, Ben Abbott <address@hidden> wrote:

On Dec 13, 2012, at 10:11 PM, Michael Noone wrote:

> OK - more attempts. I noticed some interesting things. It gives me a warning "warning: X11 DISPLAY environment variable not set". I tried loading gnuplot and then fltk, and the latter operation caused an error. Finally, after switching to fltk and doing a close all, I caused Octave to crash.
>
> I checked with Cygwin and I have "libfltk 1.1" installed already.
>
> Any of this mean anything to anybody? :) I'm including the full output below, sorry for the huge paste. Thanks!!
>
> $ octave
> ...
> warning: X11 DISPLAY environment variable not set
> octave:1> pkg load control
> octave:2> pkg load gnuplot
> octave:3> pkg load fltk
> error: package fltk is not installed
> error: called from:
> error:   /usr/share/octave/3.6.2/m/pkg/pkg.m at line 2134, column 11
> error:   /usr/share/octave/3.6.2/m/pkg/pkg.m at line 401, column 7
> octave:3> 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:4> bode(A)
> +-------------------------------Bode Diagram of A------------------------------+
> |    Magnitude [dB]                                                            |
> |     -10 ++----+---+-+-+-+++++-----+---+--+-++-++++-----+--+--+-++-++++       |
> |     -20 ++..................+.....+++++++........+..................++       |
> |     -30 ++..............................++++++......................++       |
> |     -40 ++...................................+++++++................++       |
> |     -50 ++.........................................+++++++..........++       |
> |     -60 ++...............................................++++++.....++       |
> |     -70 ++..................+....................+............++++++++       |
> |     -80 +-1---+---+-+-+-+++++0----+---+--+-++-++++1----+--+--+-++-++++2      |
> |        10                  10                   10                  10       |
> |   Phase [deg]                                                                |
> |       0 ++----+---+-+-+-+++++-----+---+--+-++-++++-----+--+--+-++-++++       |
> |     -20 ++.....++++++++++++++....................+..................++       |
> |     -60 ++.................+++++....................................++       |
> |     -80 ++.....................+++..................................++       |
> |    -100 ++.......................++++...............................++       |
> |    -140 ++..........................+++++...........................++       |
> |    -160 ++..................+...........+++++++++++++++.............++       |
> |    -180 +-1---+---+-+-+-+++++0----+---+--+-++-++++1----+--+--+-++-++++2      |
> |        10                  10                   10                  10       |
> +------------------------------------------------------------------------------+
> octave:5> graphics_toolkit
> ans = gnuplot
> octave:6> close all
> octave:7> graphics_toolkit fltk
> octave:8> bode(A)
> Can't open display:
> terminate called after throwing an instance of 'std::length_error'
>   what():  basic_string::_S_create
> Aborted

Looks like you don't have x11 installed?

Try using gnuplot's Windows terminal instead.

close all
graphics_toolkit gnuplot
setenv GNUTERM windows

plot (rand (3))

... And you'll either get a gnuplot window or an error.

Ben