i want to find out area under the curve using quad command ,the curve is generated after running the programme

clc
clear all
s=tf('s')
alpha=0.05
mu=0.05;
ztap=0;
ztaa=sqrt(3*mu/(8*(1+mu)));
omegaa=(1/(1+mu));
a1=1-alpha;
a2=2*ztaa*omegaa+2*ztap+2*ztaa*omegaa*mu;
a3=omegaa^2+4*ztap*ztaa*omegaa+mu*omegaa^2+1;
a4=2*ztap*omegaa^2+2*ztaa*omegaa;
a5=omegaa^2;
A=s^2+2*ztaa*omegaa*s+omegaa^2;
D=a1*s^4+a2*s^3+a3*s^2+a4*s+a5;
G=A/D;
bodemag(G)
After running this programme a curve is generated (bode plot) i want find out area under this curve by using quad syntax i tried to solve this many times i m very new to matlab please help me to find out the answer

Answers (1)

If you draw yourself Bode plot (see code), you receive vectors 'x' and 'y', which can be numerically integrate.
[HMag, HPhase, HOmega] = bode(G);
HMag = squeeze(HMag);
HPhase = squeeze(HPhase);
figure
semilogx(HOmega, 20*log10(HMag),'r')
xlabel('Frequency (rad/s)')
ylabel('Magnitude (dB)')
title('Bode Diagram')

Asked:

on 7 Nov 2012

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!