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 -------------------------------------