Re: animation of the PDE
- To: mathgroup at smc.vnet.net
- Subject: [mg132330] Re: animation of the PDE
- From: Alexei Boulbitch <Alexei.Boulbitch at iee.lu>
- Date: Tue, 11 Feb 2014 02:57:02 -0500 (EST)
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- Delivered-to: l-mathgroup@wolfram.com
- Delivered-to: mathgroup-outx@smc.vnet.net
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Hola! I was using Mathematica to visualise trajectories of x[p],y[p] depending on p. Is it possible? Talking about "it's simple to animate the parametric plot of them by using ParametricPlot inside Animate." But I cannot animate the NDSolve using ParametricPlot. Can you please tell me why I get errors like "NDSolve::dsvar: 1.0011952113073699` cannot be used as a variable. ": Animate[ ParametricPlot[ {Evaluate[{y[p], x[p]} /. sol = NDSolve[...some equation type D[f1[x[p],y[p],p] = -D[x[p], p], f2[x[p],y[p],p] = -D[y[p], p] x[1] == -1, y[1] == -1}, {y[p], x[p]}, {p, 1, Tp}]]}, {p, 1, Tp}], {Tp, 1, 100}] Thank you! Hi, Ljuba, Your code has nothing wrong in it except that you kept it without a precise equation. Have a look at the code below. I have only written down a simple equation containing a focus into your code: x'[p] == -y[p] - x[p]^3, y'[p] == x[p] - y[p]^3 The animation appears to be rather spectacular: Animate[ ParametricPlot[ Evaluate[{y[p], x[p]} /. NDSolve[{x'[p] == -y[p] - x[p]^3, y'[p] == x[p] - y[p]^3, x[1] == -1, y[1] == -1}, {y[p], x[p]}, {p, 1, Tp}]], {p, 1, Tp}, PlotRange -> {{-2, 2}, {-2, 2}}] /. Line -> Arrow, {Tp, 1, 30}] Try it. Have fun. Alexei Alexei BOULBITCH, Dr., habil. IEE S.A. ZAE Weiergewan, 11, rue Edmond Reuter, L-5326 Contern, LUXEMBOURG Office phone : +352-2454-2566 Office fax: +352-2454-3566 mobile phone: +49 151 52 40 66 44 e-mail: alexei.boulbitch at iee.lu