Doctrine\MongoDB\Aggregation\Stage\Group::stdDevSamp PHP Метод

The argument can be any expression as long as it resolves to an array.

См. также: https://docs.mongodb.org/manual/reference/operator/aggregation/stdDevSamp/

См. также: Expr::stdDevSamp

С версии: 1.3

public stdDevSamp ( mixed \| Expr $expression )
$expression	mixed \| Doctrine\MongoDB\Aggregation\Expr

    public function stdDevSamp($expression)
    {
        $this->expr->stdDevSamp($expression);
        return $this;
    }

Group