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Chaos from simple deterministic number function

CRcrkcity•Created May 30, 2022
Chaos from simple deterministic number function
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Instructions

Chaotic behaviour arises from very simple number transformation. Plots (blue pen dots) final results of repeating: Xnext → R*X(1-X) then shows sample of oscillations (moving red circle). If x is .01 and R=1 then Xnext time is .01(1 - .01). Keep repeating that and plot where x ends up. Then we gradually increase R, and repeat the x transformations. When R just over 3, the transformation doesn't settle on one final x, but two! That's a bifurcation (watch the red sprite). Then when R is larger, there are 4 final x oscillating, another bifurcation, then for larger R it gets really chaotic.

Description

This is chaotic behavior resulting from a deterministic and simple transformation: Xnext → R*X(1-X) That so-called logistic equation is a simple iterated transformation that has a built in limiting feedback (like a population that begins to starve after eating all it's resources). Robert May discovered this case of deterministic chaos in 1976, doing these x calculations without a fancy computer. Here, we start at x = .01 and R=1, and iterate the x transformation of 50 times, then we increase R by a bit, repeats all this until R=4. I picked 50 repetitions because the resulting x levels seems to stabilize after that many. This also and keeps code simple. Red sprite traces oscillations staring at R=2.5 (to highlight the oscillations resulint in this blue map of points). Aim is a quick and simple demonstration. (No need for turbo, and turbo makes the final oscillation demo with red sprite to quick to see)

Project Details

Project ID698729307
CreatedMay 30, 2022
Last ModifiedMay 15, 2023
SharedMay 15, 2023
Visibilityvisible
CommentsAllowed