RE: Plotting direction fields for a logistic equation
- To: mathgroup at smc.vnet.net
- Subject: [mg37217] RE: Plotting direction fields for a logistic equation
- From: "Annetts, Dave (E&M, North Ryde)" <David.Annetts at csiro.au>
- Date: Thu, 17 Oct 2002 00:08:39 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Hi Ruben,
> I've been trying to use PlotVectorField for the
> following differential equation:
> dy/dt = 0.08*y*(1-y/1000)
> but I haven't been successful yet.
> I tried to do the following:
> f[t_, y_] := {1, 0.08*y*(1 - y/1000)}
> <<Graphics`PlotField`
> PlotVectorField[f[t, y], {t, 0, 80}, {y, 0, 1400}];
> but I'm getting a meaningless plot so I'd appreciate
> if someone could tell me what is what I'm doing wrong.
> Thank you very much in advance,
> Ruben
Just a thought, but have you checked your function for typos?
As you've written it, f is only a function of y ....
Regards,
Dave.