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The Sequential class

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document.getElementById('search-input').value; window.location.href = '/search.html?query=' + query; return False } </script> </div> <div class='k-main-inner' id='k-main-id'> <div class='k-location-slug'> <span class="k-location-slug-pointer">►</span> <a href='/api/'>Keras 3 API documentation</a> / <a href='/api/models/'>Models API</a> / The Sequential class </div> <div class='k-content'> <h1 id="the-sequential-class">The Sequential class</h1> <p><span style="float:right;"><a href="https://github.com/keras-team/keras/tree/v3.7.0/keras/src/models/sequential.py#L19">[source]</a></span></p> <h3 id="sequential-class"><code>Sequential</code> class</h3> <div class="codehilite"><pre><span></span><code><span class="n">keras</span><span class="o">.</span><span class="n">Sequential</span><span class="p">(</span><span class="n">layers</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">trainable</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="kc">None</span><span class="p">)</span> </code></pre></div> <p><code>Sequential</code> groups a linear stack of layers into a <code>Model</code>.</p> <p><strong>Examples</strong></p> <div class="codehilite"><pre><span></span><code><span class="n">model</span> <span class="o">=</span> <span class="n">keras</span><span class="o">.</span><span class="n">Sequential</span><span class="p">()</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">Input</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">(</span><span class="mi">16</span><span class="p">,)))</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">layers</span><span class="o">.</span><span class="n">Dense</span><span class="p">(</span><span class="mi">8</span><span class="p">))</span> <span class="c1"># Note that you can also omit the initial `Input`.</span> <span class="c1"># In that case the model doesn&#39;t have any weights until the first call</span> <span class="c1"># to a training/evaluation method (since it isn&#39;t yet built):</span> <span class="n">model</span> <span class="o">=</span> <span class="n">keras</span><span class="o">.</span><span class="n">Sequential</span><span class="p">()</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">layers</span><span class="o">.</span><span class="n">Dense</span><span class="p">(</span><span class="mi">8</span><span class="p">))</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">layers</span><span class="o">.</span><span class="n">Dense</span><span class="p">(</span><span class="mi">4</span><span class="p">))</span> <span class="c1"># model.weights not created yet</span> <span class="c1"># Whereas if you specify an `Input`, the model gets built</span> <span class="c1"># continuously as you are adding layers:</span> <span class="n">model</span> <span class="o">=</span> <span class="n">keras</span><span class="o">.</span><span class="n">Sequential</span><span class="p">()</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">Input</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">(</span><span class="mi">16</span><span class="p">,)))</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">layers</span><span class="o">.</span><span class="n">Dense</span><span class="p">(</span><span class="mi">8</span><span class="p">))</span> <span class="nb">len</span><span class="p">(</span><span class="n">model</span><span class="o">.</span><span class="n">weights</span><span class="p">)</span> <span class="c1"># Returns &quot;2&quot;</span> <span class="c1"># When using the delayed-build pattern (no input shape specified), you can</span> <span class="c1"># choose to manually build your model by calling</span> <span class="c1"># `build(batch_input_shape)`:</span> <span class="n">model</span> <span class="o">=</span> <span class="n">keras</span><span class="o">.</span><span class="n">Sequential</span><span class="p">()</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">layers</span><span class="o">.</span><span class="n">Dense</span><span class="p">(</span><span class="mi">8</span><span class="p">))</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">layers</span><span class="o">.</span><span class="n">Dense</span><span class="p">(</span><span class="mi">4</span><span class="p">))</span> <span class="n">model</span><span class="o">.</span><span class="n">build</span><span class="p">((</span><span class="kc">None</span><span class="p">,</span> <span class="mi">16</span><span class="p">))</span> <span class="nb">len</span><span class="p">(</span><span class="n">model</span><span class="o">.</span><span class="n">weights</span><span class="p">)</span> <span class="c1"># Returns &quot;4&quot;</span> <span class="c1"># Note that when using the delayed-build pattern (no input shape specified),</span> <span class="c1"># the model gets built the first time you call `fit`, `eval`, or `predict`,</span> <span class="c1"># or the first time you call the model on some input data.</span> <span class="n">model</span> <span class="o">=</span> <span class="n">keras</span><span class="o">.</span><span class="n">Sequential</span><span class="p">()</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">layers</span><span class="o">.</span><span class="n">Dense</span><span class="p">(</span><span class="mi">8</span><span class="p">))</span> <span class="n">model</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">keras</span><span class="o">.</span><span class="n">layers</span><span class="o">.</span><span class="n">Dense</span><span class="p">(</span><span class="mi">1</span><span class="p">))</span> <span class="n">model</span><span class="o">.</span><span class="n">compile</span><span class="p">(</span><span class="n">optimizer</span><span class="o">=</span><span class="s1">&#39;sgd&#39;</span><span class="p">,</span> <span class="n">loss</span><span class="o">=</span><span class="s1">&#39;mse&#39;</span><span class="p">)</span> <span class="c1"># This builds the model for the first time:</span> <span class="n">model</span><span class="o">.</span><span class="n">fit</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="n">y</span><span class="p">,</span> <span class="n">batch_size</span><span class="o">=</span><span class="mi">32</span><span class="p">,</span> <span class="n">epochs</span><span class="o">=</span><span class="mi">10</span><span class="p">)</span> </code></pre></div> <hr /> <p><span style="float:right;"><a href="https://github.com/keras-team/keras/tree/v3.7.0/keras/src/models/sequential.py#L78">[source]</a></span></p> <h3 id="add-method"><code>add</code> method</h3> <div class="codehilite"><pre><span></span><code><span class="n">Sequential</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">layer</span><span class="p">,</span> <span class="n">rebuild</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> </code></pre></div> <p>Adds a layer instance on top of the layer stack.</p> <p><strong>Arguments</strong></p> <ul> <li><strong>layer</strong>: layer instance.</li> </ul> <hr /> <p><span style="float:right;"><a href="https://github.com/keras-team/keras/tree/v3.7.0/keras/src/models/sequential.py#L127">[source]</a></span></p> <h3 id="pop-method"><code>pop</code> method</h3> <div class="codehilite"><pre><span></span><code><span class="n">Sequential</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="n">rebuild</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> </code></pre></div> <p>Removes the last layer in the model.</p> <hr /> </div> <div class='k-outline'> <div class='k-outline-depth-1'> <a href='#the-sequential-class'>The Sequential class</a> </div> <div class='k-outline-depth-3'> <a href='#sequential-class'><code>Sequential</code> class</a> </div> <div class='k-outline-depth-3'> <a href='#add-method'><code>add</code> method</a> </div> <div class='k-outline-depth-3'> <a href='#pop-method'><code>pop</code> method</a> </div> </div> </div> </div> </div> </body> <footer style="float: left; width: 100%; padding: 1em; border-top: solid 1px #bbb;"> <a href="https://policies.google.com/terms">Terms</a> | <a href="https://policies.google.com/privacy">Privacy</a> </footer> </html>

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