Re: pursuit curve (differential equations)
- To: mathgroup at smc.vnet.net
- Subject: [mg72867] Re: pursuit curve (differential equations)
- From: dh <dh at metrohm.ch>
- Date: Tue, 23 Jan 2007 04:59:16 -0500 (EST)
- References: <ep1sq1$g13$1@smc.vnet.net>
Hi Trijezni,
you have syntax errors: "." should be "*" and is not necessery.
Functions must be written with arguments. See below.
Daniel
> hi i am doing pursuit curve in mathematica.. for instance, fox is chasing a
> rabbit - rabbit has a certain defined path (for example - a circle
> {cos(t),sin(t)}. fox always heads directly toward the rabbit.
>
> k - relative speed fox/rabbit
> p,q - rabbit's path (for instance a circle {cos(t),sin(t)}
> x,y - fox's path
> t - time :)
>
> soln = NDSolve[
> {
> x'[t] == k.Sqrt[p'[t]^2 + q'[t]^2].(p - x[t])
^ ^
> /Sqrt[(p - x[t])^2 + (q - y[t])^2],
^ ^
> y'[t] == k.Sqrt[p'[t]^2 + q'[t]^2].(y - q[t])
^ ^
> /Sqrt[(p - x[t])^2 + (q - y[t])^2],
^ ^
> x[0] == poc0[[1]],
> y[0] == poc0[[2]]
> },
> {x[t], y[t]}, {t, t0, t1}];
>
> but this wont work, any suggestions?
>