The Lorenz Attractor

The Lorenz attractor is the attractor of the dynamical system defined by the following system of differential equations.


sigma = 3;  rho = 26.5;  beta = 1;
x0 = 0;   y0 = 1;   z0 = 1;
lorenzEqs = {x'[t] == sigma (y[t] - x[t]),
             y'[t] == rho x[t]  - x[t] z[t] - y[t],
             z'[t] == x[t] y[t] - beta z[t], 
             x[0]  == 0, y[0] == 1, z[0] == 1};
Although, there is no closed form solution for this system, Mathematica can approximate a solution with NDSolve and then plot the resulting points as a function of t. Here is the necessary code:

tmin = 100;  duration = 100;
sol = NDSolve[lorenzEqs, {x[t], y[t], z[t]}, {t,tmin,tmin+duration},
	MaxSteps -> 20000];
ParametricPlot3D[{x[t], y[t], z[t], 
	RGBColor[(t-tmin)/duration,0,1-(t-tmin)/duration]} /. sol // Evaluate, 
	{t,tmin,tmin+duration}, PlotPoints -> 1000, Boxed -> False,
	Axes -> False, ViewPoint -> {4.5, 2.8, 14}]
Check out Patrick Warfolk's Lorenz attractor applet for a more dynamical view.
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