php-ml/tests/Phpml/NeuralNetwork/ActivationFunction/ThresholdedReLUTest.php
David Monllaó e83f7b95d5 Fix activation functions support (#163)
- Backpropagation using the neuron activation functions derivative
- instead of hardcoded sigmoid derivative
- Added missing activation functions derivatives
- Sigmoid forced for the output layer
- Updated ThresholdedReLU default threshold to 0 (acts as a ReLU)
- Unit tests for derivatives
- Unit tests for classifiers using different activation functions
- Added missing docs
2018-01-09 11:09:59 +01:00

54 lines
1.3 KiB
PHP

<?php
declare(strict_types=1);
namespace Phpml\Tests\NeuralNetwork\ActivationFunction;
use Phpml\NeuralNetwork\ActivationFunction\ThresholdedReLU;
use PHPUnit\Framework\TestCase;
class ThresholdedReLUTest extends TestCase
{
/**
* @dataProvider thresholdProvider
*/
public function testThresholdedReLUActivationFunction($theta, $expected, $value): void
{
$thresholdedReLU = new ThresholdedReLU($theta);
$this->assertEquals($expected, $thresholdedReLU->compute($value));
}
public function thresholdProvider(): array
{
return [
[1.0, 0, 1.0],
[0.5, 3.75, 3.75],
[0.0, 0.5, 0.5],
[0.9, 0, 0.1],
];
}
/**
* @dataProvider thresholdDerivativeProvider
*/
public function testThresholdedReLUDerivative($theta, $expected, $value): void
{
$thresholdedReLU = new ThresholdedReLU($theta);
$activatedValue = $thresholdedReLU->compute($value);
$this->assertEquals($expected, $thresholdedReLU->differentiate($value, $activatedValue));
}
public function thresholdDerivativeProvider(): array
{
return [
[0, 1, 1],
[0, 1, 0],
[0.5, 1, 1],
[0.5, 1, 1],
[0.5, 0, 0],
[2, 0, -1],
];
}
}