neuralnet.php/build/neuralnetwork/core/Genome.php

<?php

	namespace neuralnetwork\core;

	use filemanager\core\FileManager;

	class Genome/* implements \Serializable*/{

		/************************************************
		****                Constants                ****
		************************************************/
		const MIN = 0;
		const MAX = 1e9;

		/************************************************
		****             LOCAL ATTRIBUTES            ****
		************************************************/
		private $layers;   // Number of layers
		private $neurons;  // Neurons of the genome
		private $synapses; // Synapses between neurons


		/* CONSTRUCTOR
		*
		* -- RANDOM CREATION --
		* @layers<int> 											Number of layers to manage
		* @neurons<int> 										Number of neurons per layer
		*
		* -- CLONING --
		* @base<Genom>											Genome to clone to
		*
		* -- CROSS-OVER CREATION --
		* @father<Genome>										First parent
		* @mother<Genome>										Second parent
		*
		*
		*/
		public function __construct(){
			/* (1) Get arguments */
			$argv = func_get_args();
			$argc = count($argv);


			/* (2) If CrossoverCreation */
			if( $argc > 1 && $argv[0] instanceof Genome && $argv[1] instanceof Genome )
				$this->construct_crossover($argv[0], $argv[1]);

			/* (3) If RandomCreation */
			else if( $argc > 1 && abs(intval($argv[0])) === $argv[0] && abs(intval($argv[1])) === $argv[1] )
				$this->construct_new($argv[0], $argv[1]);

			/* (4) If InheritanceCreation (clone) */
			else if( $argc > 0 && $argv[0] instanceof Genome )
				$this->construct_inheritance($argv[0]);

			/* (5) If no match */
			else
				throw new \Error('Invalid Genome constructor\'s arguments.');
		}

		/* BUILDS A Genome RANDOMLY WITH PARAMETERS
		*
		* @layers<int> 											The number of hidden layers to manage
		* @neurons<int> 										The number neurons per layer
		*
		* @return created<Boolean>								If Genome has been successfully created
		*
		*/
		private function construct_new($layers=-1, $neurons=-1){
			/* (1) Checks parameters */
			if( abs(intval($layers)) !== $layers || abs(intval($neurons)) !== $neurons )
				return false;

			// set layers
			$this->layers = $layers;

			/* (2) Creating random neurons */
			$this->neurons = [];
			for( $i = 0 ; $i < $neurons ; $i++ )
				$this->neurons[$i] = rand(self::MIN, self::MAX) / self::MAX;

			/* (3) Creating random synapses */
			$this->synapses = [];
			for( $i = 0, $l = pow($neurons, $layers) ; $i < $l ; $i++ )
				$this->synapses[$i] = rand(self::MIN, self::MAX) / self::MAX;

			// Success status
			return true;
		}

		/* BUILDS A Genome BASED ON A PARENT
		*
		* @parent<Genome> 										Parent genome to clone into children
		*
		* @return created<Boolean> 								If cloned Genome has been created successfully
		*
		*/
		private function construct_inheritance($parent=null){
			/* (1) Checks parent type */
			if( !($parent instanceof Genome) )
				return false;

			/* (2) Clones into this Genome */
			$this->layers   = $parent->layers;
			$this->neurons  = $parent->neurons;
			$this->synapses = $parent->synapses;

			// Success state
			return true;
		}

		/* BUILDS A Genome BASED ON TWO PARENTS
		*
		* @father<Genome> 										First parent ($father)
		* @mother<Genome> 										Second parent ($mother)
		*
		* @return created<Boolean> 								If crossed-over Genome has been created successfully
		*
		*/
		private function construct_crossover($father=null, $mother=null){
			/* (1) Checks parent type */
			if( !($father instanceof Genome) || !($mother instanceof Genome) )
				return false;

			/* (2) Checks number of layers+neurons (same species) */
			if( $father->layers !== $mother->layers || count($father->neurons) !== count($mother->neurons) )
				return false;

			/* (3) Do random crossover for neurons */
			$this->neurons = [];
			for( $i = 0, $l = count($father->neurons) ; $i < $l ; $i++ )
				if( rand(0,1) ) $this->neurons[$i] = $father->neurons[$i];
				else            $this->neurons[$i] = $mother->neurons[$i];

			/* (3) Creating random synapses */
			$this->synapses = [];
			for( $i = 0, $l = pow(count($this->neurons), $this->layers) ; $i < $l ; $i++ )
				if( rand(0,1) ) $this->synapses[$i] = $father->synapses[$i];
				else            $this->synapses[$i] = $mother->synapses[$i];

			// Success state
			return true;
		}

	}




	/************************************************
	****                 USE CASE                ****
	************************************************/
	$use_case = false;
	if( $use_case ){

		/* (1) Basic Creation */
		$a = new Genome(2, 3); // 2 layers of 3 neurons each -> randomly filled

		/* (2) Inheritance */
		$b = new Genome($a);   // Clone of @a

		/* (3) Section Title */
		$b->mutation(0.3); // @b has now mutated with a threshold of 30%

		/* (4) Cross-over (father+mother) */
		$c = new Genome($a, $b); // @c is a randomly-done mix of @a and @b

	}

?>