Piwik\Plugins\VisitFrequency\Reports\Get::configureView PHP Method

    public function configureView(ViewDataTable $view)
    {
        if ($view->isViewDataTableId(Sparklines::ID)) {
            $view->requestConfig->apiMethodToRequestDataTable = 'VisitFrequency.get';
            $this->addSparklineColumns($view);
            $view->config->addTranslations($this->getSparklineTranslations());
            $numberFormatter = NumberFormatter::getInstance();
            $view->config->filters[] = function (DataTable $table) use($numberFormatter) {
                $firstRow = $table->getFirstRow();
                if ($firstRow) {
                    $value = $firstRow->getColumn('nb_visits_returning');
                    if (false !== $value) {
                        $firstRow->setColumn('nb_visits_returning', $numberFormatter->formatNumber($value));
                    }
                    $value = $firstRow->getColumn('nb_actions_returning');
                    if (false !== $value) {
                        $firstRow->setColumn('nb_actions_returning', $numberFormatter->formatNumber($value));
                    }
                    $value = $firstRow->getColumn('nb_actions_per_visit_returning');
                    if (false !== $value) {
                        $firstRow->setColumn('nb_actions_per_visit_returning', $numberFormatter->formatNumber($value, 1));
                    }
                    $value = $firstRow->getColumn('bounce_rate_returning');
                    if (false !== $value) {
                        $firstRow->setColumn('bounce_rate_returning', $numberFormatter->formatNumber($value, $precision = 1));
                    }
                }
            };
        }
    }