Piwik\Plugins\CoreVisualizations\Visualizations\Sparklines\Config::getSparklineOrder PHP Method

    private function getSparklineOrder($order)
    {
        if (!isset($order)) {
            // make sure to append to the end if nothing set (in the order they are added)
            $order = 999 + count($this->sparklines);
        }
        return (int) $order;
    }