% Example of J.D. Farmer, Chaotic Attractors of an Infinite-Dimensional
% Dynamical System, Physica D, 4 (1982) 366-393. The Mackey-Glass 
% equation is a scalar equation that exhibits chaotic behavior.  Fig. 
% 2a starts the plot with t = 50 to let an initial transient settle down.

sol = dde23('exer2f',14,0.5,[0, 300]);

t = linspace(50,300,1000);
y = ddeval(sol,t);
ylag = ddeval(sol,t - 14);
plot(y,ylag)
title('Exercise 2.  Fig. 2a of Farmer.')
xlabel('y(t)');
ylabel('y(t-14)');