How should I make a Bode Plot of a Multiple Input and multiple Output System

I have a simulink file with two outports and two inports. What is wrong with my m-file below?

 [A,B,C,D] = linmod('SimFileName');
 wmin = 1;  nmax = 5;  Npoints = 200;   
 w = logspace(wmin,wmax,Npoints);  
 system = ss(A,B,C,D);
 [mag,phase] = bode(system,w);  
 for k=1:Npoints
    magdBout1in1 = 20*log10(mag(1:1:k)); 
    magdBout2in1 = 20*log10(mag(2:1:k));
    phaseOut1in1 = phase(1:1:k);
    phaseOut2in1 = phase(2:1:k);
end
figure(2);clf;     
subplot(2,1,1);
loglog(w,magdBout1in1,'-',w,magdBout2in1,'--');grid;
subplot(2,1,2);
semilogx(w,phaseOut1in1,'-',w,phaseOut2in1,'--');grid;|

Answer 1

[Arkadiy Turevskiy]

There seem to be several things that are wrong. For example:

1. You define a variable nmax, but the script is using wmax - looks like it is a typo
2. In the for loop body you keep overriding the variables on the left side of the assignment statements

If I understand correctly what you are trying to do, it seems you can do that in a simpler way like this:

    bode(system(1,1),w);
    hold on;
    bode(system(1,2),w,'--');
    grid;

HTH.

[Meinrad]

You are right , that s much simpler. Thank you.