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Torsten
Posts:
1,717
Registered:
11/8/10


Re: Logistic equation with delay
Posted:
Mar 21, 2014 3:55 AM


"Adin" wrote in message <lggbgg$95h$1@newscl01ah.mathworks.com>... > I am trying to solve a logistic equation with delay WITHOUT using dde23. So the delay is of the form: ddtN(t)=N(t)(abN(t?t)),a>0,b>0 > > I have a function called logistic that looks like this: > function dN = logistic(t,N) > global a b; > dN = (aN.*b)*N; > > And another file that calls this function with ode45 like this: > global a b; > a = 4; > b = 1; > [t, N] = ode45('logistic', [0:.01:5], 10); > >
ok, here you try to solve the _continuous_ logistic equation without delay.
> I think I understand how to write a forloop to calculate the logistic equation with delay of 1 since I'm picking my ? to be 1; but I'm not getting the correct results. Here is the code: > S=zeros(501,1); > t=zeros(501,1); > S(1)=0; > > for iterate=1:501 > S(i) = S(i1) + r*S(i1)*(1b*S(i1)) > end > plot(t,S) >
ok, here you try to solve the _discrete_ logistic equation without delay (although the case S(1)=0 is not that interesting)
> > Any ideas?
And where do you try to solve the continuous logistic equation with delay ?
Best wishes Torsten.



