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05-momentum.html

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<title>動量：給梯度下降加慣性｜Momentum: Adding Inertia to Gradient Descent</title>
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<div class="wrap">
<div class="bar"><div class="t">動量：給梯度下降加慣性<small>Momentum: Adding Inertia to Gradient Descent · 16:9 互動式資訊圖表</small></div></div>
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<canvas id="c" width="3200" height="1800"></canvas>
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</div>
<div class="controls" id="controls">
<button id="runBtn" type="button">跑 40 步</button>
<button id="resetBtn" type="button" class="alt">重設</button>
<label>學習率 η <input type="range" id="eta" min="0.01" max="0.12" step="0.01" value="0.05"><output id="etav">0.05</output></label>
<label>動量係數 α <input type="range" id="alpha" min="0" max="0.9" step="0.05" value="0.7"><output id="alphav">0.70</output></label>
</div>
<div class="hint" id="hint"><b>操作：</b>調整 η 與 α 後按「跑 40 步」，比較純梯度下降（紅）與動量（綠）在狹長山谷中的軌跡；若線條中斷並顯示發散，表示 η 相對曲率太大。</div>
</div>
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/* ================= 頁面內容 ================= */
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P('直覺：像把球推下山，慣性抹平左右搖晃。',990,650,545,30,14.5,400,C.ink);
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header('動量：給梯度下降加慣性','Momentum: Adding Inertia to Gradient Descent','IDL115','Ch.3 §2.4');
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strip(40,828,1520,56,'動量 = 梯度下降 + 慣性；不只看腳下，還記得剛才往哪走','Momentum = GD + inertia: remember where you were heading');
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