public function setDayOfWeekFromString($day)
{
@(list($weekNumberString, $dayNumberString) = explode(' ', $day));
// get day number
$day = Weekly::getDayIntFromString($dayNumberString) % 7;
// get week number
$weekNumberString = strtolower($weekNumberString);
if (isset(self::$weekNumberStringToInt[$weekNumberString])) {
$week = self::$weekNumberStringToInt[$weekNumberString];
} else {
throw new Exception("Invalid week describer in Schedule\\Monthly::setDayOfWeekFromString: '{$weekNumberString}'. " . "Supported values are 'first', 'second', 'third', 'fourth'.");
}
$this->setDayOfWeek($day, $week);
}
