% Figure 6.1:
om=[-pi:0.01:pi];
bart=(1/2/pi/gam)*(sin(gam*om/2)./sin(om/2)).^2;
parz=1/2/pi/gam^3*4*(2+cos(om)).*(sin(gam*om/4)./sin(om/2)).^4;
ham=1/8/pi*(2*(sin((gam+1/2)*om))./sin(om/2)+...
              (sin((gam+1/2)*(om-pi/gam))./sin((om-pi/gam)/2))...
             +(sin((gam+1/2)*(om+pi/gam))./sin((om+pi/gam)/2)));
plot(om,bart,':',om,parz,'-',om,ham,'--')

xlabel('(rad/s)'),ylabel('W_\gamma(\xi)')
set(gca,'ytick',[0  0.4 0.8])
set(gca,'xtick',[-3 0 3])
 
