README: live site link
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src/fput-chain/README.mdmodified+2−0View file
@@ -6,6 +6,8 @@ Current state: N masses (2 to 64, default 4) between two fixed walls, joined by
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77 "Sped up · listen" (open by default, below the cards; otherwise as in the pendulum app): the header says how much faster it runs ("the whole decay, 321× faster: 62 min of motion in 12 s"; without damping "321× faster than the chain above"). The page starts muted (the mute button is tinted red and reads "Muted"; muted notes are still computed and shown); the audio context is created at the first Strike; closing the panel stops the note. While it is open each Strike plays a note, the same strike rendered in a Web Worker (`src/render-worker.ts`) sped up so the lowest linear mode sounds at the Pitch (30 to 1000 Hz, default 100; the readout gives the lowest and highest mode pitches). A damped note is the whole decay, ending when its energy has fallen to 1e-6 of the strike's (-60 dB; predicted length (tau/2) ln 1e6 of physical time, 11.6 s of sound by default, measured 11.3 s; capped at twice that); undamped notes last 10 s. "Strike to hear the whole decay." shows until the first note; the status line gives the signal and note length ("computing…" while rendering). Replay plays the last strike again with the current settings (to compare signals). Signal (`src/signals.ts`): velocity (default), displacement or acceleration of mass j (default 1, the end mass, which is never at a node), force on the left wall (the first spring's tension), or sum of accelerations (the net wall force, in which even modes cancel). In one mass's motion mode n is weighted by sqrt(E_n) / omega_n, sqrt(E_n) or sqrt(E_n) omega_n. Each note is made zero-mean, scaled to a 0.9 peak (all signals equally loud; Volume sets the level) and faded out over its last 20 ms (`src/sound.ts`). Chips (as in the pendulum app): Spectrogram (on; pendulum's `NoteSpectrogram`: 2048-sample Hann, zero-pad 4096, hop 512; dashed lines at the linear mode pitches, drawn only while at least 6 px apart, since crowded together their dashes merged into a solid on-off bar at the bottom), Lyapunov (the note's largest Lyapunov exponent over the last 10 s of physical time, from a shadow run in the worker alongside the note; the first 5 s of physical time left out of the y range), Energy (log scale, so the decay is a straight line) and λ vs E (`src/scatter.ts` from the pendulum app: one point per 256 samples, accumulated over notes, log energy axis, colored by time into the note on a log scale, earlier notes faded, hover for values, Clear button). The first three span the whole note (strike at left, end at right) and fill in as the audio clock reaches each sample; one shared cursor (playhead while playing; hover for values, click to pin). Pause (or space) pauses the animation and the sound (audio context suspended). Render time in the browser pane (with the Lyapunov shadow): ~0.6 s for N = 4, ~2 s for N = 32 (default strike). First look (N = 4, 2.51 J): λ ~1.3 /s at the strike, falling to ~0 by ~4 s of sound as the spectrogram resolves into lines; on λ vs E the note's points sit near 0 below ~0.1 J and rise to ~1.4 /s at the top.
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9+Live site: https://fput-chain-chaos--listening-for-chaos.vault1-sites.magland.org/ (built and deployed by `.github/workflows/pages.yml` on every push to main).
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911 ```bash
1012 npm install
1113 npm run dev