Pickover¶
A Pickover (Clifford-style) 3-D ornamental attractor map.
Definition¶
@staticmethod
def _step(X, a, b, c, d):
x, y = X
xp = np.sin(a * y) + c * np.cos(a * x)
yp = np.sin(b * x) + d * np.cos(b * y)
return xp, yp
Parameters¶
| Symbol | Default | Role |
|---|---|---|
a |
-1.4 |
angular frequency scaling the coordinates |
b |
1.6 |
angular frequency scaling the coordinates |
c |
1 |
amplitude of the cosine contribution |
d |
0.7 |
amplitude of the cosine contribution |
Properties¶
Lyapunov spectrum
$+0.303,\; -0.1131$
computed at build
computed at build
Kaplan–Yorke dimension
$D_{KY} = 2$
Divergence ∇·f
n/a — discrete map — flow divergence undefined (per-step contraction is |det J|)
Equilibria
1 fixed points
0 stable · 1 unstable
0 stable · 1 unstable
Define it in TSDynamics¶
import tsdynamics as ts
sys = ts.systems.Pickover()
traj = sys.iterate(steps=10_000)
exps = sys.lyapunov_spectrum()
ts.kaplan_yorke_dimension(exps)
Reference¶
Pickover (1990), Computers, Pattern, Chaos and Beauty (St. Martin's Press)
