Nonlinear pendulum with friction --- transient chaos at high amplitude, decay to limit cycle or fixed point
Standard analysis sees: rich, high-entropy values; smooth / autocorrelated; long-range memory (persistent); strongly periodic; low-complexity (predictable, not noise-like); volatility-clustering (bursty); low-dimensional. The atlas additionally detects Persistent Homology:max_h1_lifetime, Multifractal Spectrum:hurst_estimate. It sits beside Period-Doubled Wave in the atlas (standard-bank rank 41) — a neighbor conventional features miss.
Chladni:modal_nodal_cascade | -4.5z | bank-miss 1.2σ |
Visibility Graph:degree_exponent_gamma | -2.8z | bank-miss 1.3σ |
Bispectrum:bicoherence_concentration | -2.3z | bank-miss 1.1σ |
Laplacian:curvature_autocorrelation | +2.0z | bank-miss 1.2σ |









_(centered)/signed_log_z/Damped_Pendulum.png)
_(centered)/xy_path/Damped_Pendulum.png)

/barcode/Damped_Pendulum.png)
/d_curve/Damped_Pendulum.png)








/phi_spectrum/Damped_Pendulum.png)










/default/Damped_Pendulum.png)
/default/Damped_Pendulum.png)


| Nearest neighbor | Distance | |
|---|---|---|
| Sine Wave | 2.49 | cross-origin |
| Period-Doubled Wave | 3.31 | cross-origin |
| Triangle Wave | 3.38 | cross-origin |
Attractor Reconstruction › Attractor Reconstruction:d2_saturation | rank 2/307 | 0.9972 |
Chladni › Chladni:modal_nodal_cascade | rank 307/307 | -0.6527 |
Fisher Information › Fisher Information:velocity_spectral_gini | rank 5/307 | 0.7780 |
H² × ℝ (Thurston) › H² × ℝ (Thurston):hyperbolic_variance | rank 3/307 | 3.3435 |
Multi-Scale Wasserstein › Multi-Scale Wasserstein:w_std | rank 5/307 | 0.1389 |
Navier-Stokes › Navier-Stokes:sl_fit_quality | rank 304/307 | -0.9946 |
Nonstationarity › Nonstationarity:metric_volatility | rank 4/307 | 3.2640 |
Ordinal Partition › Ordinal Partition:time_irreversibility | rank 305/307 | 0.0038 |
Persistent Homology › Persistent Homology:max_h1_lifetime | rank 3/307 | 0.8862 |
Spectral Analysis › Spectral Analysis:spectral_peakedness | rank 4/307 | 0.9698 |
Visibility Graph › Visibility Graph:degree_exponent_gamma | rank 305/307 | 0.2986 |