New in Wolfram Mathematica 7: Delay Differential Equations ◄ previous | next ►
Solve a Chaotic Delay Differential Equation
Enter a delay differential equation in standard mathematical format, then immediately solve it. This shows a solution of the Mackey-Glass equation; for the parameter values chosen the solution is chaotic.
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mge = {x'[t] == 0.4 x[t - 18]/(1 + x[t - 18]^10) - 0.2 x[t], 

   x[t /; t <= 0] == 1/2};
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sol = NDSolve[mge, x, {t, 500, 1000}]
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ParametricPlot[{x[t], x[t - 18]} /. sol, {t, 518, 1000}, 

 Frame -> True, FrameLabel -> {x[t], x[t - 18]}]
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