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<h1 id="simulation-evaluation">Simulation &amp; Evaluation</h1>
<p>The simulation pipeline allows you to visualize trained models and evaluate their performance under various conditions.</p>
<h2 id="overview">Overview</h2>
<p>The simulation pipeline is metadata-driven. Training-specific configurations (morphology, arena, environment, etc.) are automatically loaded from the <code>_metadata.yaml</code> file associated with the model checkpoint.</p>
<h2 id="basic-simulation">Basic Simulation</h2>
<p>To simulate a model in the MuJoCo viewer:</p>
<div class="highlight"><pre><span></span><code>uv<span class="w"> </span>run<span class="w"> </span>scripts/simulate.py<span class="w"> </span>simulation.model_path<span class="o">=</span>runs/your_run/final_model.flax
</code></pre></div>
<h2 id="amputation-morphology-overrides">Amputation &amp; Morphology Overrides</h2>
<p>You can test trained models on different morphologies (e.g., amputating legs) by providing a morphology override. The observations will be automatically padded up to the training morphology's dimensions:</p>
<div class="highlight"><pre><span></span><code>uv<span class="w"> </span>run<span class="w"> </span>scripts/simulate.py<span class="w"> </span><span class="se">\</span>
<span class="w">    </span>simulation.model_path<span class="o">=</span>runs/your_run/final_model.flax<span class="w"> </span><span class="se">\</span>
<span class="w">    </span>simulation.morphology_override<span class="o">=</span>configs/morphology/3_arms.yaml
</code></pre></div>
<h2 id="video-recording">Video Recording</h2>
<p>Recording videos requires the <code>[evaluation]</code> extra:</p>
<div class="highlight"><pre><span></span><code>uv<span class="w"> </span>run<span class="w"> </span>scripts/simulate.py<span class="w"> </span><span class="se">\</span>
<span class="w">    </span>simulation.model_path<span class="o">=</span>runs/your_run/final_model.flax<span class="w"> </span><span class="se">\</span>
<span class="w">    </span>simulation.record_video<span class="o">=</span><span class="nb">true</span><span class="w"> </span><span class="se">\</span>
<span class="w">    </span>simulation.max_steps<span class="o">=</span><span class="m">1000</span>
</code></pre></div>
<p>Videos and evaluation metadata are stored in timestamped folders alongside the model:
<code>runs/your_run/final_model_evaluations/eval_&lt;timestamp&gt;/simulation.mp4</code></p>
<p>For batch evaluation and cross-model comparison, see the <strong><a href="../evaluation/">Evaluation Guide</a></strong>.</p>


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