MATLAB sample files

Differential Delay Equations

To simulate differential delay equation models, you need SIX m-files:
Four m files are required for various purposes:
dde23.m, ddeget.m, ddeset.m, ddeval.m
The other two deal with specific model equationss and graphing commands, respectively.

1:  stagepp.m    This file records the equations of a predator-prey model with stage structure.
    dx/dt = x(1-x)-ypx/(1+ax);
    dy/dt = bexp(-dj\tau)y(t-\tau)px(t-\tau)/(1+ax(t-\tau))-dy-my^2;

     stageppf.m  This file contains plotting commands.

2:  A logistic type equation with distributed delay, y'=a y(1-y-b\int^1_0 y(t-s)ds)-by
     logdist.m   logdistfig.m

3: Solutions of y'=ay(1-\int^t_{t-1} y(s)ds) with different transformations
     logdist1.m    logdist2.m       logdistf.m

4:  tumor1.m, tumor1f.m