convertTimestamp.php

// Converts a UTC timezone to a GMT - or + timezone - github.com/smugzombie
// Accepts a timestamp like this: Y-m-d H:i:s
// And a timezone like this: (0,1,8,-8,-12)
// Example $time_out = convertTimestamp("2016-05-16 20:13:44","-7"); // 2016-05-16 21:13:44

function convertTimestamp($time_in, $time_zone){
	  $time_zone = floatval($time_zone); //Ensure Timezone is a number, if not replace with 0 (UTC)
    if(strpos($time_zone, "-") === false){$modifier = "+";}else{ $modifier = "";} //See if modifier is needed, add + if positive
    $time_out = date('Y-m-d H:i:s',strtotime("$time_in $modifier$time_zone hour")); // Convert
    $tz = "GMT $modifier$time_zone";
    if($time_zone == "0.0" || $time_zone == "0"){ $tz = "UTC"; }
    return $time_out." ($tz)";
}