b4e1602FPUT chain chaos: struck FPUT-beta chain with damping, real-time plots, ghost, Lyapunov, and a sped-up listen panelJeremy Magland 1
2<html lang="en">
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6 <title>FPUT chain chaos</title>
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104 </style>
105 </head>
106 <body>
107 <main>
108 <header><h1>FPUT chain chaos</h1></header>
109 <div class="grid">
110 <section class="card">
111 <canvas id="chain"></canvas>
112 <div id="controls">
113 <div class="row">
114 <button id="strike" class="primary">Strike</button>
115 <select id="strike-kind">
116 <option value="mode">mode</option>
117 <option value="mass" selected>mass</option>
118 </select>
119 <input id="strike-index" type="number" min="1" value="1" step="1" />
120 <button id="pause" disabled>Pause</button>
121 </div>
122 <div class="row">
123 <span class="muted">Strike energy</span>
124 <input id="energy" type="range" min="-5" max="2" step="0.01" value="0.4" />
125 <span id="energy-value" class="num"></span>
126 </div>
127 <div class="row">
128 <span class="muted">Masses</span>
129 <input id="n" type="number" min="2" max="64" step="1" value="4" />
130 <span class="muted" style="margin-left: 12px">Speed</span>
131 <select id="speed">
132 <option value="0.1">0.1×</option>
133 <option value="0.25">0.25×</option>
134 <option value="0.5">0.5×</option>
135 <option value="1" selected>1× (real time)</option>
136 <option value="2">2×</option>
137 <option value="5">5×</option>
138 </select>
139 </div>
140 </div>
141 <div id="ghost-row" class="row">
142 <label class="chip" title="A second chain started with every mass moved by a tiny offset"><input id="ghost-toggle" type="checkbox" /><span>Ghost</span></label>
143 <span id="ghost-controls" class="row" hidden>
144 <span class="muted">Offset</span>
145 <input id="ghost-offset" type="range" min="-12" max="-1" step="1" value="-10" aria-label="Ghost offset (power of ten, m)" />
146 <span id="ghost-offset-value" class="num"></span>
147 <button id="ghost-reset" type="button" title="Restart the ghost from the chain's current state">Restart ghost</button>
148 </span>
149 <span id="ghost-sep" class="num muted"></span>
150 </div>
151 <details>
152 <summary>Parameters</summary>
153 <div id="param-form">
154 <label>m <input id="p-m" type="number" step="any" /> <span class="unit">kg</span></label>
155 <label>k <input id="p-k" type="number" step="any" /> <span class="unit">N/m</span></label>
156 <label>k3 <input id="p-k3" type="number" step="any" /> <span class="unit">N/m³</span></label>
157 <label>a <input id="p-a" type="number" step="any" /> <span class="unit">m (spacing)</span></label>
158 <label>τ <input id="p-tau" type="number" step="any" /> <span class="unit">s (decay, 0 = off)</span></label>
159 </div>
160 <div id="param-actions" class="row">
161 <button id="param-apply">Apply</button>
162 <span id="param-status"></span>
163 </div>
164 <div id="params"></div>
165 </details>
166 </section>
167 <section class="card">
168 <div class="card-head">Real time</div>
169 <div class="chips">
170 <label class="chip"><input id="bars-toggle" type="checkbox" checked /><span>Mode bars</span></label>
171 <span id="toggles"></span>
172 </div>
173 <figure id="bars">
174 <canvas id="modes"></canvas>
175 <div id="mode-stats" class="num muted"></div>
176 </figure>
177 <div id="traces"></div>
178 </section>
179 </div>
180 <details class="card panel" id="sound" open>
181 <summary><span class="label">Sped up · listen</span> <span id="sound-clock" class="muted"></span></summary>
182 <div class="row">
183 <button id="mute" type="button" class="mute" title="Unmute" aria-label="Unmute"></button>
184 <label><span class="label">Signal</span> <select id="signal"></select></label>
185 <input id="sound-mass" type="number" min="1" step="1" value="1" aria-label="Mass" />
186 <label><span class="label">Volume</span> <input id="volume" type="range" min="0" max="1" step="0.01" value="0.5" /></label>
187 <button id="replay" type="button" disabled title="Play the last strike again with the current settings">Replay</button>
188 <span id="sound-chips" class="chips">
189 <label class="chip"><input id="spec-toggle" type="checkbox" checked /><span>Spectrogram</span></label>
190 </span>
191 </div>
192 <div class="row">
193 <label class="grow"><span class="label">Pitch</span> <input id="pitch" type="range" min="1.477" max="3" step="0.001" value="2" aria-label="Pitch of the lowest mode" /></label>
194 <span id="pitch-value" class="num"></span>
195 </div>
196 <div class="row"><span id="sound-status" class="muted"></span></div>
197 <p id="sound-hint" class="muted">Strike to hear the whole decay.</p>
198 <figure id="spec-fig"><div id="spectrogram"></div></figure>
199 <div id="sound-traces"></div>
200 <figure id="scatter-fig" hidden>
201 <div id="scatter"></div>
202 <div class="row scatter-actions"><button id="scatter-clear" type="button">Clear</button></div>
203 </figure>
204 </details>
205 </main>
206 <script type="module" src="/src/main.ts"></script>
207 </body>
208</html>