Cobweb: trajectory in (x, f(x)) space. Measure: time spent at each x (invariant measure ρ). Basin: initial conditions coloured by period of eventual orbit.
Lyapunov Exponent
λ(r) across the full parameter range
r samples800
Orbit length1200
hover r—
λ(r)—
onset r∞≈ 3.5699
Green λ < 0 — stable, ordered. Red λ > 0 — chaotic, sensitive.
λ = 0 marks bifurcation points.
The period-3 window (≈3.828–3.857) appears as a green notch inside the red band.
Feigenbaum Cascade
δ = ratio of successive doubling intervals → 4.6692…
Bisection depth50
Doublings n7
Last δₙ—
Exact δ4.6692016…
Error—
Uses bisection on the super-stable r (where x = 0.5 is a periodic point of f^(2ⁿ)). More doublings and greater depth converge the ratio toward δ.
Top canvas: bifurcation tree zoomed near r∞. Table: rₙ and δₙ for each period-doubling.