GuckenheimerHolmes¶
Systems / ODEs / Chaotic attractors
A symmetric flow with a structurally stable heteroclinic cycle — the prototype of cycling chaos, slowing near each saddle in turn.
Definition¶
\[
\begin{aligned}
\dot{x} &= a x - b y + c x z + d x^{2} z + d y^{2} z \\
\dot{y} &= a y + b x + c y z \\
\dot{z} &= - a z^{3} + e - f x^{2} - f y^{2} - z^{2}
\end{aligned}
\]
Parameters¶
| Symbol | Default | Role |
|---|---|---|
a |
0.4 |
linear growth/rotation coefficient |
b |
20.25 |
linear growth/rotation coefficient |
c |
3 |
linear growth/rotation coefficient |
d |
1.6 |
nonlinear coupling coefficient |
e |
1.7 |
nonlinear coupling coefficient |
f |
0.44 |
nonlinear coupling coefficient |
State variables: x, y, z
Properties¶
Lyapunov spectrum
TODO — lyapunov_spectrum failed: AttributeError
Kaplan–Yorke dimension
TODO — requires a numeric Lyapunov spectrum
Divergence ∇·f
$\nabla\!\cdot f = - 3 a z^{2} + 2 a + 2 c z + 2 d x z - 2 z$
state-dependent
state-dependent
Equilibria
2 equilibria
0 stable · 2 unstable
0 stable · 2 unstable
Use it in TSDynamics¶
import tsdynamics as ts
system = ts.systems.GuckenheimerHolmes()
traj = system.run(final_time=100.0, dt=0.01)
ts.plot(traj)
spectrum = ts.analysis.lyapunov_spectrum(system)
ts.analysis.kaplan_yorke_dimension(spectrum)
Reference¶
Guckenheimer & Holmes (1988), Math. Proc. Camb. Phil. Soc. 103, 189-192
doi:10.1017/s0305004100064732