• Suppose that G(s) is the transfer matrix from (F1 , F2) to (x1 , x2); that is,
•
• and suppose k1=1, k2 =4, b1 =0.2, b2 = 0.1, m1 =1, and m2=2 with appropriate units.
• >>G=pck(A,B,C,D);
• >>hinfnorm(G,0.0001) or linfnorm(G,0.0001) % relative error £0.0001
• >>w=logspace(-1,1,200);  %200 points between 0.1=10-1 and 10=101;
• >>Gf=frsp(G,w); %computing frequency response;
• >>[u,s,v]=vsvd(Gf); %SVD at each frequency;
• >>vplot(‘liv,lm’,s), grid  %plot both singular values and grid.
• ||G||₯ =11.47=the peak of the largest singular value Bode plot in Figure 4.3.