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Topic: Logistic equation with delay
Replies: 8   Last Post: Mar 24, 2014 3:42 AM

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 Torsten Posts: 1,631 Registered: 11/8/10
Re: Logistic equation with delay
Posted: Mar 24, 2014 3:42 AM

"Adin" wrote in message <lgi88s\$etr\$1@newscl01ah.mathworks.com>...
> This is what I have so far:
>
> N1=zeros(201,1);
> t=zeros(201,1);
> t(1)=0;
> N1(1)=10;
> N1(2)=20;
> delta = 1;
> h=1;
>
> for i=2:200
> t(i)=i-1;
> d=(delta * t(i-1));
> N1(i+1) = N1(i) + h*N1(i)*(a-b*N1(i-d));
> end
> plot(t,N1(:,1)), grid on;
>
> But I'm getting weird plots like this: http://i.imgur.com/4NeseF6.png
>
> Any ideas what I'm doing wrong?

N1=zeros(201,1);
N1(1)=10;
N1(2)=20;
delta = 1;
h=1;
for i=2:200
N1(i+1)=N1(i)+h*N1(i)*(a-b*N1(i-delta));
end

But - as I told you - this is the discrete form of the delayed logistic equation, not the continuous form.

Best wishes
Torsten.

Date Subject Author
3/20/14 Sankar
3/21/14 Torsten
3/21/14 Sankar
3/21/14 Torsten
3/21/14 Sankar
3/21/14 Torsten
3/21/14 Steven Lord
3/21/14 Sankar
3/24/14 Torsten