Re: xlabel not visible on plot

[Lukas Reichlin]

> > > > > I had been unaware the aquaterm could save its windows contents as
> > > > > eps (pdf too).
> > > > >
> > > > > In any event, line 45 of gca.m is (should be) ...
> > > > >
> > > > >         h = axes ();
> > > > >
> > > > > What happens if you type
> > > > >
> > > > >         clear all
> > > > >         close all
> > > > >         axes
> > > > >         plot (1:10)
> > > > >
> > > > > also, what does your path look like (just type "path")?
> > > > >
> > > > > Ben
> > > >
> > > > Yes, line 45 is
> > > >         h = axes ();
> > > >
> > > > For the first time,
> > > >         clear all
> > > >         close all
> > > >         axes
> > > >         plot(1:10)
> > > > delivered a simple plot. Then I tried to run the m-file again. It
> > > > didn't work, I got the same error message as before. Afterwards, I
> > > > tried those four commands again and I got the following error:
> > > > error: invalid use of script in index expression
> > > > error: called from:
> > > > error:   /Applications/Octave/Octave.app/Contents/Resources/share/
> > > > octave/3.2.0/m/plot/gca.m at line 45, column 9
> > > > error:   /Applications/Octave/Octave.app/Contents/Resources/share/
> > > > octave/3.2.0/m/plot/__plt_get_axis_arg__.m at line 63, column 4
> > > > error:   /Applications/Octave/Octave.app/Contents/Resources/share/
> > > > octave/3.2.0/m/plot/plot.m at line 178, column 18
> > >
> > > I installed the control package and I tried your script with
> > > octave-3.2.x (developers sources). I do not get the error above.
> > >
> > > Please try running the script I've attached (it is yours from your
> > > initial email, with the axes position changed).
> > >
> > > If it works for you, please send me a script that does not work.
> > >
> > > Ben
> > > <lukas.m>
> >
> >
> > Thank you. I'm sorry, but it still doesn't work. I get
> >
> > error: invalid use of script in index expression
> > error: called from:
> > error:   /Applications/Octave/Octave.app/Contents/Resources/share/
> > octave/3.2.0/m/plot/gca.m at line 45, column 9
> > error:   /Applications/Octave/Octave.app/Contents/Resources/share/
> > octave/3.2.0/m/plot/__plt_get_axis_arg__.m at line 63, column 4
> > error:   /Applications/Octave/Octave.app/Contents/Resources/share/
> > octave/3.2.0/m/plot/semilogx.m at line 32, column 18
> > error:   /Users/lukas/lukas.m at line 79, column 1
> >
> > Line 79 is the semilogx command. May I have to delete some kind of
> > "Preference" files?
>
> Regarding "preferences", you can check to see what might be in  
> ~/.octaverc
>
> For the sake of being thorough, I downloaded both the ppc and i386  
> versions of Octave-3.2.0. The script ran cleanly for me on both a  
> PPC based Mac and a i386 (each running 10.5.7).
>
> Thus, it does appear you have a problem local to your installation.  
> In the event you have inadvertently modified a core function, you  
> might try a fresh install.
>
> Ben

I did a fresh install of Octave, Gnuplot and Aquaterm and  
deleted .octaveverc. But I still get:

error: invalid use of script in index expression
error: called from:
error:   /Applications/Octave/Octave.app/Contents/Resources/share/ 
octave/3.2.0/m/plot/gca.m at line 45, column 9
error:   /Applications/Octave/Octave.app/Contents/Resources/share/ 
octave/3.2.0/m/plot/__plt_get_axis_arg__.m at line 63, column 4
error:   /Applications/Octave/Octave.app/Contents/Resources/share/ 
octave/3.2.0/m/plot/semilogx.m at line 32, column 18
error:   /Users/lukas/OCTAVE/test.m at line 62, column 1

even with the simplified m-file below.

I tried
        clear all
        close all
        axes
        plot(1:10)
It worked for the first time, from the second on I got:

error: invalid use of script in index expression
error: called from:
error:   /Applications/Octave/Octave.app/Contents/Resources/share/ 
octave/3.2.0/m/plot/gca.m at line 45, column 9
error:   /Applications/Octave/Octave.app/Contents/Resources/share/ 
octave/3.2.0/m/plot/__plt_get_axis_arg__.m at line 63, column 4
error:   /Applications/Octave/Octave.app/Contents/Resources/share/ 
octave/3.2.0/m/plot/plot.m at line 178, column 18


Are there any other files than .octaveverc to delete?

Regards,
Lukas





SIMPLIFIED M-FILE:

% Heat Exchanger


% Tabula Rasa
clear all;
close all;
clc;


% Physical Parameters
m_star_1 = 0.5;  % kg/s
m_star_2 = 0.2;  % kg/s
V_1 = 0.01;      % m^3
V_2 = 0.02;      % m^3

rho = 1000;      % kg/m^3
c = 4200;        % J/(kg K)
Ar = 2;          % m^2
k = 2000;        % W/(m^2 K)


% Control-Oriented Parameters
tau_1 = rho * V_1 * c / ( m_star_1 * c  +  k * Ar );
tau_2 = rho * V_2 * c / ( m_star_2 * c  +  k * Ar );

sigma_1 = k * Ar / ( m_star_1 * c  +  k * Ar );
sigma_2 = k * Ar / ( m_star_2 * c  +  k * Ar );

beta_1 = m_star_1 * c / ( m_star_1 * c  +  k * Ar );
beta_2 = m_star_2 * c / ( m_star_2 * c  +  k * Ar );


% System Matrices
A = [      -1/tau_1    sigma_1/tau_1 ;
      sigma_2/tau_2         -1/tau_2 ];

B = [ beta_1/tau_1               0 ;
                 0    beta_2/tau_2 ];

C = [ 1    0 ;
      0    1 ];

D = [ 0    0 ;
      0    0 ];


% Singular Value Plot
w = logspace(-3, 1, 1000);   % rad/s

for k = 1 : size(w, 2)
        
        % Frequency Response Matrix
        P = C * inv(i * w(k) * eye(size(A))  -  A) * B  +  D;
        
        % Singular Value Decomposition
        sigma = svd(P);
        sigma_max(k) = max(sigma);
        sigma_min(k) = min(sigma);
end

figure(1)
semilogx(w, 20*log10(sigma_max), w, 20*log10(sigma_min))
xlabel('Frequency [rad/s]')
ylabel('Singular Values [dB]')
grid on