2017-09-02 19:30:35 +00:00
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<?php
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declare(strict_types=1);
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namespace Phpml\NeuralNetwork\ActivationFunction;
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use Phpml\NeuralNetwork\ActivationFunction;
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class ThresholdedReLU implements ActivationFunction
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{
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/**
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* @var float
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*/
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private $theta;
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2018-01-09 10:09:59 +00:00
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public function __construct(float $theta = 0.0)
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2017-09-02 19:30:35 +00:00
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{
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$this->theta = $theta;
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}
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/**
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* @param float|int $value
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*/
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2017-11-22 21:16:10 +00:00
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public function compute($value): float
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2017-09-02 19:30:35 +00:00
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{
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return $value > $this->theta ? $value : 0.0;
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}
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2018-01-09 10:09:59 +00:00
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/**
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* @param float|int $value
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* @param float|int $calculatedvalue
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*/
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public function differentiate($value, $calculatedvalue): float
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{
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return $calculatedvalue >= $this->theta ? 1.0 : 0.0;
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}
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2017-09-02 19:30:35 +00:00
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}
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