· Labs · Bifurcation & Chaos Lab
Essay: The Tao of Chaos →
Bifurcation Diagram
xₙ₊₁ = r · xₙ(1 − xₙ) · r ∈ [2.5, 4]
Iterations200
Warm-up (skip)100
r range2.500 – 4.000
hover r
period est.
Drag canvas to pan the r-window.
Scroll wheel to zoom in/out.
Double-click to reset.

Gold = periodic orbit · Purple = upper attractor · Teal = lower attractor.
Cobweb & Attractor
Orbit geometry at a single r value
Growth rate r3.800
Iterations500
r3.800
Lyapunov λ
Period
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.
nrₙ (super-stable)δₙ = gap ratioerror vs δ