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<ol class="chapter"><li class="chapter-item expanded "><a href="juice.html"><strong aria-hidden="true">1.</strong> Juice</a></li><li class="chapter-item expanded "><a href="layers.html"><strong aria-hidden="true">2.</strong> Layers</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="layer-lifecycle.html"><strong aria-hidden="true">2.1.</strong> Layer Lifecycle</a></li><li class="chapter-item expanded "><a href="building-networks.html"><strong aria-hidden="true">2.2.</strong> Create a Network</a></li><li class="chapter-item expanded "><a href="create-new-layer.html"><strong aria-hidden="true">2.3.</strong> Create a new Layer</a></li></ol></li><li class="chapter-item expanded "><a href="solvers.html" class="active"><strong aria-hidden="true">3.</strong> Solvers</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="optimize-layers.html"><strong aria-hidden="true">3.1.</strong> Optimize Layers</a></li><li class="chapter-item expanded "><a href="multi-device-optimization.html"><strong aria-hidden="true">3.2.</strong> Multi-Device Optimization</a></li><li class="chapter-item expanded "><a href="distributed-optimization.html"><strong aria-hidden="true">3.3.</strong> Distributed Optimization</a></li></ol></li><li class="chapter-item expanded "><a href="backend.html"><strong aria-hidden="true">4.</strong> Backend</a></li><li class="chapter-item expanded "><a href="deep-learning-glossary.html"><strong aria-hidden="true">5.</strong> Glossary</a></li><li class="spacer"></li><li class="chapter-item expanded "><a href="api-docs.html"><strong aria-hidden="true">6.</strong> Rust API Documentation</a></li></ol>
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<h1 class="menu-title">juice documentation</h1>
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<h1 id="solvers"><a class="header" href="#solvers">Solvers</a></h1>
<p>Solvers optimize the layer with a given objective. This might happen
by updating the weights of the layer, which is the usual practice for
Neural Networks but is not limited to this kind of learning.</p>
<p>A solver can have different learning (solving) policies. With Neural Networks, it
is common to use a Stochastic Gradient Descent based approach
like Adagrad, whereas for a classical regression the solving might be
done via a maximum likelihood estimation.</p>
<p>Similar to <code>Layer</code>s, we can construct a <a href="https://github.com/spearow/juice/blob/master/juice/src/solver/mod.rs"><code>Solver</code> (<em>/src/solver/mod.rs</em>)</a>
from a <a href="https://github.com/spearow/juice/blob/master/juice/src/solver/mod.rs"><code>SolverConfig</code> (<em>/src/solver/mod.rs</em>)</a>.
When passing this <code>SolverConfig</code> (e.g. an Adagrad <code>SolverConfig</code>) to the
<code>Solver::from_config</code> method, a <code>Solver</code> with the behavior
of the config is returned.</p>
<p>The most characteristic feature of the <code>SolverConfig</code> is its <code>network</code>
and <code>objective</code> fields. These two fields expect one <code>LayerConfig</code> each. When
passing the <code>SolverConfig</code> to the <code>Solver::from_config</code> method, the
<code>LayerConfig</code> of the <code>network</code> and <code>objective</code> fields are turned into
an initialized <code>Layer</code> and provided to the returned, <code>Solver</code>.</p>
<pre><pre class="playground"><code class="language-rust">
<span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>// set up a Solver
let mut solver_cfg = SolverConfig { minibatch_size: batch_size, base_lr: learning_rate, momentum: momentum, .. SolverConfig::default() };
solver_cfg.network = LayerConfig::new("network", net_cfg);
solver_cfg.objective = LayerConfig::new("classifier", classifier_cfg);
let mut solver = Solver::from_config(backend.clone(), backend.clone(), &solver_cfg);
<span class="boring">}
</span></code></pre></pre>
<p>The now initialized <code>Solver</code> can be feed with data to optimize the <code>network</code>.</p>
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