ex05ch4.m

these codes are for solving OED with matlab

function sol = ex05ch4
sol = dde23(@ddes,14,0.5,[0, 300]);
t = linspace(50,300,1000);
y = deval(sol,t);
ylag = deval(sol,t - 14);
plot(y,ylag)
xlabel('y(t)');
ylabel('y(t-14)');
%==================================
function dydt = ddes(t,y,Z)
dydt = 0.2*Z / (1 + Z^10) - 0.1*y;