36 lines
692 B
PHP
36 lines
692 B
PHP
<?php
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declare(strict_types=1);
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namespace Phpml\Math\Distance;
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use Phpml\Exception\InvalidArgumentException;
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use Phpml\Math\Distance;
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class Euclidean implements Distance
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{
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/**
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* @param array $a
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* @param array $b
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*
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* @return float
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*
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* @throws InvalidArgumentException
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*/
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public function distance(array $a, array $b): float
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{
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if (count($a) !== count($b)) {
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throw InvalidArgumentException::arraySizeNotMatch();
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}
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$distance = 0;
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$count = count($a);
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for ($i = 0; $i < $count; ++$i) {
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$distance += pow($a[$i] - $b[$i], 2);
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}
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return sqrt((float) $distance);
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}
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}
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