Chaos Lab

Discrete map · 1D · dim 1

Logistic map

Robert May's 1976 review introduced this one-parameter quadratic family as the canonical example of complex dynamics from simple rules. It is the type-specimen of the period-doubling route to chaos and the source of the Feigenbaum constants.

Bifurcation diagram of the logistic map, r ∈ [2.5, 4]. Period-doubling cascade visible from r ≈ 3 to r∞ ≈ 3.57.

Equations

x_{n+1} = r · x_n · (1 − x_n)

At a glance

Parametersr ∈ [0, 4]
Chaotic forr ≈ 3.5699 ≤ r ≤ 4 (chaotic windows and periodic islands)
Lyapunov exponentλ(r = 4) = ln 2 ≈ 0.6931
HistoryMay (1976), Feigenbaum (1978).

Try it

Open the interactive playground at /tools/logistic.

See also

Quick quiz

Test yourself on logistic

8 multiple-choice questions. Pick an answer for each, then submit to see explanations.

  1. Q1.The logistic map x_{n+1} = r·x_n·(1 − x_n) becomes chaotic for r above:

  2. Q2.Lyapunov exponent of the logistic map at r = 4 equals:

  3. Q3.The Feigenbaum constant δ is approximately:

  4. Q4.Between r = 3 and r ≈ 3.4495 the orbit is:

  5. Q5.Robert May popularised this map in:

  6. Q6.A famous period-3 window is centred near:

  7. Q7.Logistic, sine, and tent maps all share the universal:

  8. Q8.What does r = 1 mark?

0 of 8 answered