Entity::getFilterOperator

private function getFilterOperator(array $field, $operator)
{
	$result = '';
	if ($operator === '')
		$operator = 'default';
	if (!empty($field['operators']) && is_array($field['operators']))
	{
		if (isset($field['operators'][$operator]))
			$result = $field['operators'][$operator];
		elseif (isset($field['operators']['default']))
			$result = $field['operators']['default'];
	}
	return $result;
}