Fibonacci Retracement Function written in PHP

fibonacci_retracement.php

<?php
//If $Reverse option was set true, return value will be use reversed Fibonacci retracement.
//Return value is always desc.
function FibRet($High,$Low,$Reverse=false) {
    $FibNum=array(
        0,
        0.236,
        0.382,
        0.5,
        0.618,
        0.786,
        1
    );
    if($Reverse==true) {
        rsort($FibNum);
        list($High, $Low) = array($Low, $High);
    }
    $Store=null;
    foreach ($FibNum as $item) {
        $Store[] = $High-($High-$Low)*$item;
    }
    return $Store;
}