Where does my impedance problem come from?

Good morning, I have a problem with my matlab code to plot my impedance module according to frequency. The problem is that I can't find my error despite the help of the documentation.

Here is my matlab code

if true
  close all
clear all
pas = 10;
F= (0:pas:20000);
w= 2*pi*F;
x= w.^2;
Re= 9.54;
Le= 0.19;
Lem= 0.000011*5.07;
Rem= (5.07^2)/1.905;
Cem= 0.011/5.05;
Cer1= 5.07^2/(13.2*0.18);
Cer2= Cer1;
Z= Re+1i*w*Le+((1i*w*Lem)/(1+1i*w*(Lem/Rem)-(Cer1+Cer2+Cem)*Lem*x));
Fr= ((1/(2*pi))*(1/(Lem*(Cem+Cer1+Cer2))));
R=abs(Z);
f=(1:10:20000);
figure, loglog(f,R,'r');
xlabel('Fréquence', 'fontSize',15);
ylabel('Impédance acoustique Z', 'fontsize', 15);

end

Answer 1

[Kim Winter]

Hi, I believe that your issue is when you plot loglog. When you plot, for every x value, you should have a corresponding y value. If you check the lengths of f and R respectively, f is 2001 points and R is 2000 points. So, if instead, you plotted:

figure, loglog(f,R(2:end),'r');

or

figure, loglog(f,R(1:end-1),'r');

a figure will show.