Solving delay differential equations with DDE23. Tutorial + Examples.
exer1
function sol = exer1
% Example 1 of K.W. Neves, Automatic integration
% of functional differential equations: an approach,
% ACM TOMS, 1 (1975) 357-368.
% Copyright 2004, The MathWorks, Inc.
sol = dde23(@exer1f,[1, 0.5],@exer1h,[0, 1]);
figure
plot(sol.x,sol.y);
title('Example 1 of Neves.')
xlabel('time t');
ylabel('y(t)');
%-----------------------------------------------------------------------
function yp = exer1f(t,y,Z)
%EXER1F The derivative function for Exercise 1 of the DDE Tutorial.
ylag1 = Z(:,1);
ylag2 = Z(:,2);
yp = [ ylag1(5) + ylag1(3)
ylag1(1) + ylag2(2)
ylag1(3) + ylag2(1)
ylag1(5)*ylag1(4)
ylag1(1) ];
%-----------------------------------------------------------------------
function y = exer1h(t)
%EXER1H The history function for Exercise 1 of the DDE Tutorial.
temp = exp(t+1);
y = [ temp; exp(t+0.5); sin(t+1); temp; temp];