fig107.m

realize analysis and design for computer-controlled system

% Generates Fig 10.7
% Computer Controlled Systems (3rd ed)
% Author: B. Wittenmark
% Last edit: 1997-07-10
% Copyright (c) 1996 by K. J. 舠tr鰉, B. Wittenmark and
% Department of Automatic Control, Lund Institute of
% Technology, Lund, Sweden

newplot;clf;
set(gcf,'PaperUnits','centimeters','PaperPosition',[2 2 13 7.5])
set(gcf,'Units','centimeters','position',get(gcf,'PaperPosition'))

lw=0.9;
den=[1 -3 4.5 -3 1];
num=0.25*[1 2.5 1];
pol=roots(den);
zer=roots(num);
a=real(poly([pol(3),pol(4)]));
b=sqrt(num(1))*poly(zer(2));
hpl=plot(real(pol),imag(pol),'kx','Linew',lw);
set(hpl,'Markersize',6);
hold on
plot(real(zer),imag(zer),'ko','Linew',lw)
t=0:.1:6.3;
plot(sin(t),cos(t),'k-','Linew',lw)
axis('equal')
axis([-2.5 1.7, -1.2 1.2]);
plot([0 2*real(pol(1))],[0 2*imag(pol(1))],'k:','Linew',lw)
plot([0 2*real(pol(2))],[0 2*imag(pol(2))],'k:','Linew',lw)
plot([0 2*real(zer(1))],[0 2*imag(zer(1))],'k:','Linew',lw)
set(gca,'Fontsize',9,'Fontname','NewCenturySchlbk');
set(gca,'ytick',[-1 0 1]);
set(gca,'xtick',[-2 -1 0 1]);
xlabel('Real','Fontname','NewCenturySchlbk','Fontsize',9)
ylabel('Imaginary','Fontname','NewCenturySchlbk','Fontsize',9)