JuliaDynamics / JuliaDynamics/NonlinearDynamicsTextbook

Error in Fig 8.2

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accepted correction figure
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Julia
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Description

Figure 8.2b shows the boundary map of a mushroom billiard, with a chaotic and two regular trajectories and the regular island shaded in gray. However, the shaded area seems to be too small: one of the regular trajectories (the teal one) is outside the regular island in the cap.
Looking at the dimensions of this mushroom, the sin(θ) of the chaotic band in the cap should be within ±0.1 (the critical angle is sin(θ_c) = w/2R).

This error can't be reproduced with the corresponding script in this repo (8.3.jl) since the shading seems to be a later addition.

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Research direction

Inspect Figure 8.2b and run the corresponding 8.3.jl script to understand the mushroom dimensions and trajectories. Locate where the later shading was added, then verify that the chaotic band in the cap has sin(θ) within ±0.1 and that the teal trajectory lies inside the shaded regular island.

Written by the indexing model from the issue text.

Assessment

Tech stack
julia
Domain
data-visualization, documentation
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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