Re: Laplace Trasform system of differential equation

*To*: mathgroup at smc.vnet.net*Subject*: [mg122062] Re: Laplace Trasform system of differential equation*From*: Helen Read <readhpr at gmail.com>*Date*: Tue, 11 Oct 2011 04:24:41 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <j6rk79$1oo$1@smc.vnet.net> <j6uacn$f1g$1@smc.vnet.net>

PlotStyle does work in ParametricPlot3D. There is no need to remove it. Helen On 10/10/2011 4:29 AM, Dr. Wolfgang Hintze wrote: > "elos"<marusik_92 at inbox.ru> schrieb im Newsbeitrag > news:j6rk79$1oo$1 at smc.vnet.net... >> where I made a mistake? I need to solve the system of differential >> equations using Laplace transforms and the plots. Solve happened, but >> no graphics. >> >> >> odeSys = {x'[t] - x[t] + y[t] == 0, >> y'[t] - x[t] - y[t] == 0, >> z'[t] - x[t] - y[t] - 2*z[t] == 0} >> eq1 = LaplaceTransform[odeSys, t, s] >> eq2 = Solve[eq1, {LaplaceTransform[x[t], t, s], >> LaplaceTransform[y[t], t, s], >> LaplaceTransform[z[t], t, s]}] >> sol1 = Map[InverseLaplaceTransform >> [#, s, t]&, eq2, {3}] /. {x[0] -> 1, y[0] -> 1, z[0] -> 1} >> sol2 = DSolve[{odeSys, x[0] == 1, y[0] == 1, z[0] == 1}, >> {x[t], y[t], z[t]}, t] // Simplify >> ParametricPlot[Evaluate[{x[t], y[t], z[t]} /. sol1], >> {t, 0, 1}, PlotStyle -> {Hue[0.5], Thickness[0.01]}] >> >> >> Here is system of differential equations: x'[t]=x[t]-y[t] >> >> y'[t]=x[t]+y[t] >> >> z'[t]=x[t]+y[t]+2*z[t] >> > Slight modifications of your code are sufficient for remedy > > 1) you need to use ParametricPlot3D > 2) this function does not have the option PlotStle, so remove it > > Hope this helps > > Wolfgang > >