Symfony3 Highcharts pie chart blank - symfony

Question

I started with Highcharts today in a symfony3 project and have the line charts working great. I'm having trouble rendering a pie chart and I'm beating my head on the wall trying to figure out why it's not working.
I can reproduce the basic pie chart (like this one) if I render directly in javascript in my twig template, and it looks as expected. BUT if I try to render from my controller I get a blank image where the pie chart should be. My chart title is there so I know I'm rendering to the correct div. But the chart is blank. I've even tried very simple data structures (like an array of numbers as suggested by the docs) with no luck. This must be something simple. Help!
My controller:
public function piechartAction()
{
$data = [["name"=> 'Microsoft Internet Explorer', "y"=> 56.33],
["name"=> 'Chrome', "data"=> 24.03],
["name"=> 'Firefox', "y"=> 10.38],
["name"=> 'Safari', "y"=> 4.77],
["name"=> 'Opera', "y"=> 0.91],
["name"=> 'Proprietary or Undetectable', "y"=> 0.2]];
$ob = new Highchart();
$ob->chart->renderTo('container');
$ob->chart->type('pie');
$ob->title->text('My Pie Chart');
$ob->series(array("data"=>$data));
return $this->render('dashboard/test.html.twig', [
'mypiechart' => $ob
]);
}
And my twig template:
{% extends 'base.html.twig' %}
{% block javascripts %}
{{ parent() }}
<script src="//code.highcharts.com/highcharts.js"></script>
<script src="//code.highcharts.com/modules/exporting.js"></script>
<script>
jQuery(document).ready(function() {
{{ chart(mypiechart) }}
});
</script>
{% endblock %}
{% block body %}
<div id="container" style="min-width: 310px; height: 400px; max-width: 600px; margin: 0 auto"></div>
{% endblock %}

Answer 1

I solved this. For anyone looking in the future, here's what I had wrong:
My setting of series data was not the correct format.
Here's my new (working) controller:
public function piechartAction()
{
$data = [
['Microsoft Internet Explorer', 56.33],
['Chrome', 24.03],
['Firefox', 10.38],
['Safari', 4.77],
['Opera', 0.91],
['Proprietary or Undetectable', 0.2]
];
$ob = new Highchart();
$ob->chart->renderTo('container');
$ob->chart->type('pie');
$ob->title->text('My Pie Chart');
$ob->series(array(array("data"=>$data)));
return $this->render('dashboard/test.html.twig', [
'mypiechart' => $ob
]);
}
I found this by studying the "cookbook" associated with this bundle (here); there is a listing for a drill-down pie chart.