/**
* Returns the day of the year for a date as a number between 1 and 366.
*
* The argument can be any expression as long as it resolves to a date.
*
* @see http://docs.mongodb.org/manual/reference/operator/aggregation/dayOfYear/
* @see Expr::dayOfYear
* @param mixed|Expr $expression
* @return self
*/
public function dayOfYear($expression)
{
$this->expr->dayOfYear($expression);
return $this;
}