64 lines
1.3 KiB
PHP
64 lines
1.3 KiB
PHP
<?php
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declare(strict_types=1);
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namespace Phpml\Helper\Optimizer;
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use Closure;
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use Exception;
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abstract class Optimizer
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{
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/**
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* Unknown variables to be found
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*
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* @var array
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*/
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protected $theta = [];
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/**
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* Number of dimensions
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*
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* @var int
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*/
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protected $dimensions;
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/**
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* Inits a new instance of Optimizer for the given number of dimensions
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*/
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public function __construct(int $dimensions)
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{
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$this->dimensions = $dimensions;
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// Inits the weights randomly
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$this->theta = [];
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for ($i = 0; $i < $this->dimensions; ++$i) {
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$this->theta[] = random_int(0, getrandmax()) / (float) getrandmax();
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}
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}
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/**
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* Sets the weights manually
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*
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* @return $this
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*
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* @throws \Exception
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*/
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public function setInitialTheta(array $theta)
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{
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if (count($theta) != $this->dimensions) {
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throw new Exception("Number of values in the weights array should be $this->dimensions");
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}
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$this->theta = $theta;
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return $this;
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}
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/**
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* Executes the optimization with the given samples & targets
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* and returns the weights
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*/
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abstract public function runOptimization(array $samples, array $targets, Closure $gradientCb);
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}
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