76 lines
1.4 KiB
PHP
76 lines
1.4 KiB
PHP
<?php
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declare (strict_types = 1);
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namespace Phpml\NeuralNetwork\Node;
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use Phpml\NeuralNetwork\ActivationFunction;
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use Phpml\NeuralNetwork\Node\Neuron\Synapse;
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use Phpml\NeuralNetwork\Node;
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class Neuron implements Node
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{
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/**
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* @var Synapse[]
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*/
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protected $synapses;
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/**
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* @var ActivationFunction
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*/
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protected $activationFunction;
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/**
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* @var float
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*/
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protected $output;
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/**
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* @param ActivationFunction|null $activationFunction
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*/
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public function __construct(ActivationFunction $activationFunction = null)
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{
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$this->activationFunction = $activationFunction ?: new ActivationFunction\Sigmoid();
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$this->synapses = [];
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$this->output = 0;
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}
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/**
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* @param Synapse $synapse
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*/
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public function addSynapse(Synapse $synapse)
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{
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$this->synapses[] = $synapse;
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}
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/**
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* @return Synapse[]
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*/
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public function getSynapses()
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{
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return $this->synapses;
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}
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/**
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* @return float
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*/
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public function getOutput(): float
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{
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if (0 === $this->output) {
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$sum = 0;
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foreach ($this->synapses as $synapse) {
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$sum += $synapse->getOutput();
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}
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$this->output = $this->activationFunction->compute($sum);
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}
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return $this->output;
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}
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public function refresh()
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{
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$this->output = 0;
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}
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}
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