Re: ORDINARY DIFFERENTIAL EQUATION
- To: mathgroup at smc.vnet.net
- Subject: [mg32182] Re: ORDINARY DIFFERENTIAL EQUATION
- From: "Carl T. Bergstrom" <cbergst at nospam.u.washington.edu>
- Date: Fri, 4 Jan 2002 05:03:58 -0500 (EST)
- References: <a0ugmj$5t3$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
> I am trayin to plot the directin of vector field of system of ordinary
> differential equation but i could not
>
> the system is
> x'[t]=(1-x[t]-0.5 y[t])x[t]
> y'[t]=(1-y[t]-0.8 x[t])y[t]
>
How about
<<Graphics`PlotField`
v[x_,y_]:={(1-x-0.5 y)x, (1-y-0.8 x)y}
PlotVectorField[v[x,y], {x,0,1}, {y,0,1}, ScaleFactor->.25]
Of course, you can make the picture a lot prettier using David Park's DrawGraphics
packages; see http://home.earthlink.net/~djmp/ if you want to take this
approach.
-----------------------
Carl T. Bergstrom
Department of Zoology
University of Washington
http://octavia.zoology.washington.edu
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