/**
* @param Unit $unit
* @param int $root
* @param string $quantity
* @param string $symbol
*
* @return CompoundUnit
*/
public static function getRootInstance(Unit $unit, $root, $quantity = '', $symbol = '')
{
if ($unit instanceof CompoundUnit) {
$elements = [];
foreach ($unit->getElements() as $element) {
$gcd = self::gcd(abs($element->pow), $element->root * $root);
$elements[] = new CompoundElement($element->unit, $element->pow / $gcd, $element->root * $root / $gcd);
}
} else {
$elements = [new CompoundElement($unit, 1, $root)];
}
return self::getInstance($elements, [], $quantity, $symbol);
}
