Phpml\Classification\Linear\Adaline

Complexity

Total Complexity

3

Size/Duplication

Total Lines	66
Duplicated Lines	13.64 %

Coupling/Cohesion

Components	1
Dependencies	1

Importance

Changes

0

2 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	11	2
A	runTraining()	9	17	1

<?php

declare(strict_types=1);

namespace Phpml\Classification\Linear;

use Phpml\Classification\Classifier;

class Adaline extends Perceptron
{

    /**
     * Batch training is the default Adaline training algorithm
     */
    const BATCH_TRAINING    = 1;

    /**
     * Online training: Stochastic gradient descent learning
     */
    const ONLINE_TRAINING    = 2;

    /**
     * Training type may be either 'Batch' or 'Online' learning
     *
     * @var string
     */
    protected $trainingType;

    /**
     * Initalize an Adaline (ADAptive LInear NEuron) classifier with given learning rate and maximum
     * number of iterations used while training the classifier <br>
     *
     * Learning rate should be a float value between 0.0(exclusive) and 1.0 (inclusive) <br>
     * Maximum number of iterations can be an integer value greater than 0 <br>
     * If normalizeInputs is set to true, then every input given to the algorithm will be standardized
     * by use of standard deviation and mean calculation
     *
     * @param int $learningRate
     * @param int $maxIterations
     */
    public function __construct(float $learningRate = 0.001, int $maxIterations = 1000,
        bool $normalizeInputs = true, int $trainingType = self::BATCH_TRAINING)
    {
        if (! in_array($trainingType, [self::BATCH_TRAINING, self::ONLINE_TRAINING])) {
            throw new \Exception("Adaline can only be trained with batch and online/stochastic gradient descent algorithm");
        }

        $this->trainingType = $trainingType;

The property $trainingType was declared of type string, but $trainingType is of type integer. Maybe add a type cast?

        parent::__construct($learningRate, $maxIterations, $normalizeInputs);
    }

    /**
     * Adapts the weights with respect to given samples and targets
     * by use of gradient descent learning rule
     */
    protected function runTraining()
    {
        // The cost function is the sum of squares
        $callback = function ($weights, $sample, $target) {

This code seems to be duplicated across your project.

            $this->weights = $weights;

            $output = $this->output($sample);
            $gradient = $output - $target;
            $error = $gradient ** 2;

            return [$error, $gradient];
        };

        $isBatch = $this->trainingType == self::BATCH_TRAINING;

        return parent::runGradientDescent($callback, $isBatch);

It seems like you call parent on a different method (runGradientDescent() instead of runTraining()). Are you sure this is correct? If so, you might want to change this to $this->runGradientDescent().

    }
}