Add activationFunction parameter for Perceptron and Layer

toolsets · Aug 11, 2016 · 2412f15 · 2412f15
1 parent c506a84
commit 2412f15
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Showing 2 changed files with 29 additions and 10 deletions.
diff --git a/src/Phpml/NeuralNetwork/Layer.php b/src/Phpml/NeuralNetwork/Layer.php
@@ -15,22 +15,38 @@ class Layer
     private $nodes = [];
 
     /**
-     * @param int    $nodesNumber
-     * @param string $nodeClass
+     * @param int                     $nodesNumber
+     * @param string                  $nodeClass
+     * @param ActivationFunction|null $activationFunction
      *
      * @throws InvalidArgumentException
      */
-    public function __construct(int $nodesNumber = 0, string $nodeClass = Neuron::class)
+    public function __construct(int $nodesNumber = 0, string $nodeClass = Neuron::class, ActivationFunction $activationFunction = null)
     {
         if (!in_array(Node::class, class_implements($nodeClass))) {
             throw InvalidArgumentException::invalidLayerNodeClass();
         }
 
         for ($i = 0; $i < $nodesNumber; ++$i) {
-            $this->nodes[] = new $nodeClass();
+            $this->nodes[] = $this->createNode($nodeClass, $activationFunction);
         }
     }
 
+    /**
+     * @param string                  $nodeClass
+     * @param ActivationFunction|null $activationFunction
+     *
+     * @return Neuron
+     */
+    private function createNode(string $nodeClass, ActivationFunction $activationFunction = null)
+    {
+        if (Neuron::class == $nodeClass) {
+            return new Neuron($activationFunction);
+        }
+
+        return new $nodeClass();
+    }
+
     /**
      * @param Node $node
      */

diff --git a/src/Phpml/NeuralNetwork/Network/MultilayerPerceptron.php b/src/Phpml/NeuralNetwork/Network/MultilayerPerceptron.php
@@ -5,6 +5,7 @@
 namespace Phpml\NeuralNetwork\Network;
 
 use Phpml\Exception\InvalidArgumentException;
+use Phpml\NeuralNetwork\ActivationFunction;
 use Phpml\NeuralNetwork\Layer;
 use Phpml\NeuralNetwork\Node\Bias;
 use Phpml\NeuralNetwork\Node\Input;
@@ -14,18 +15,19 @@
 class MultilayerPerceptron extends LayeredNetwork
 {
     /**
-     * @param array $layers
+     * @param array                   $layers
+     * @param ActivationFunction|null $activationFunction
      *
      * @throws InvalidArgumentException
      */
-    public function __construct(array $layers)
+    public function __construct(array $layers, ActivationFunction $activationFunction = null)
     {
         if (count($layers) < 2) {
             throw InvalidArgumentException::invalidLayersNumber();
         }
 
         $this->addInputLayer(array_shift($layers));
-        $this->addNeuronLayers($layers);
+        $this->addNeuronLayers($layers, $activationFunction);
         $this->addBiasNodes();
         $this->generateSynapses();
     }
@@ -39,12 +41,13 @@ private function addInputLayer(int $nodes)
     }
 
     /**
-     * @param array $layers
+     * @param array                   $layers
+     * @param ActivationFunction|null $activationFunction
      */
-    private function addNeuronLayers(array $layers)
+    private function addNeuronLayers(array $layers, ActivationFunction $activationFunction = null)
     {
         foreach ($layers as $neurons) {
-            $this->addLayer(new Layer($neurons, Neuron::class));
+            $this->addLayer(new Layer($neurons, Neuron::class, $activationFunction));
         }
     }