gmarche/vendor/fzaninotto/faker/test/Faker/Provider/BiasedTest.php

75 lines
2.8 KiB
PHP

<?php
namespace Faker\Test\Provider;
use Faker\Provider\Biased;
use Faker\Generator;
use PHPUnit\Framework\TestCase;
class BiasedTest extends TestCase
{
const MAX = 10;
const NUMBERS = 25000;
protected $generator;
protected $results = array();
protected function setUp()
{
$this->generator = new Generator();
$this->generator->addProvider(new Biased($this->generator));
$this->results = array_fill(1, self::MAX, 0);
}
public function performFake($function)
{
for($i = 0; $i < self::NUMBERS; $i++) {
$this->results[$this->generator->biasedNumberBetween(1, self::MAX, $function)]++;
}
}
public function testUnbiased()
{
$this->performFake(array('\Faker\Provider\Biased', 'unbiased'));
// assert that all numbers are near the expected unbiased value
foreach ($this->results as $number => $amount) {
// integral
$assumed = (1 / self::MAX * $number) - (1 / self::MAX * ($number - 1));
// calculate the fraction of the whole area
$assumed /= 1;
$this->assertGreaterThan(self::NUMBERS * $assumed * .95, $amount, "Value was more than 5 percent under the expected value");
$this->assertLessThan(self::NUMBERS * $assumed * 1.05, $amount, "Value was more than 5 percent over the expected value");
}
}
public function testLinearHigh()
{
$this->performFake(array('\Faker\Provider\Biased', 'linearHigh'));
foreach ($this->results as $number => $amount) {
// integral
$assumed = 0.5 * pow(1 / self::MAX * $number, 2) - 0.5 * pow(1 / self::MAX * ($number - 1), 2);
// calculate the fraction of the whole area
$assumed /= pow(1, 2) * .5;
$this->assertGreaterThan(self::NUMBERS * $assumed * .9, $amount, "Value was more than 10 percent under the expected value");
$this->assertLessThan(self::NUMBERS * $assumed * 1.1, $amount, "Value was more than 10 percent over the expected value");
}
}
public function testLinearLow()
{
$this->performFake(array('\Faker\Provider\Biased', 'linearLow'));
foreach ($this->results as $number => $amount) {
// integral
$assumed = -0.5 * pow(1 / self::MAX * $number, 2) - -0.5 * pow(1 / self::MAX * ($number - 1), 2);
// shift the graph up
$assumed += 1 / self::MAX;
// calculate the fraction of the whole area
$assumed /= pow(1, 2) * .5;
$this->assertGreaterThan(self::NUMBERS * $assumed * .9, $amount, "Value was more than 10 percent under the expected value");
$this->assertLessThan(self::NUMBERS * $assumed * 1.1, $amount, "Value was more than 10 percent over the expected value");
}
}
}