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Highlights from
Tutorial on solving DDEs with DDE23

  • exam1
  • exam1
  • exam2
  • exam2
  • exam3
  • exam3
  • exam4
  • exam4
  • exam5
  • exam5
  • exam6 This is a demonstration problem for CTMS/BD in
  • exam6 This is a demonstration problem for CTMS/BD in
  • exam7 An example from C. Marriott and C. DeLisle, Effects
  • exam7 An example from C. Marriott and C. DeLisle, Effects
  • exam8 This is the suitcase problem from Suherman, et al.,
  • exam8 This is the suitcase problem from Suherman, et al.,
  • exer1 Example 1 of K.W. Neves, Automatic integration
  • exer1 Example 1 of K.W. Neves, Automatic integration
  • exer2 Example of J.D. Farmer, Chaotic Attractors of an
  • exer2 Example of J.D. Farmer, Chaotic Attractors of an
  • exer3 Wheldon's model of chronic granuloctic leukemia
  • exer3 Wheldon's model of chronic granuloctic leukemia
  • exer5
  • exer5
  • exer6 Sample problem of ARCHI manual. The absolute error
  • exer6 Sample problem of ARCHI manual. The absolute error
  • exer7 Marchuk immunology model of E. Hairer, S.P. Norsett, and
  • exer7 Marchuk immunology model of E. Hairer, S.P. Norsett, and
  • prob1 This system of ODE's is taken from 'An Introduction to Nuermcial Methods
  • prob1 This system of ODE's is taken from 'An Introduction to Nuermcial Methods
  • prob2 This problem considers a cardiovascular model, which can be found in
  • prob2 This problem considers a cardiovascular model, which can be found in
  • prob2b This problem considers a cardiovascular model, which can be found in
  • prob2b This problem considers a cardiovascular model, which can be found in
  • prob3 This problem is epidemic model due to Cooke, more information can be
  • prob3 This problem is epidemic model due to Cooke, more information can be
  • prob4 This problem is an epidemic model due to Cooke et alia, more information
  • prob4 This problem is an epidemic model due to Cooke et alia, more information
  • prob5 This problem population growth model due to Cooke et alia, more information
  • prob5 This problem population growth model due to Cooke et alia, more information
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from Tutorial on solving DDEs with DDE23 by Jacek Kierzenka
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];

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