Rails + Javascript +图形-如果我使用变量，则Javascript不起作用

Question

I'm using the google charts for show some graphs in my rails app.

I get a code example in internet and I'm testing in my app, but I'm with some dubs and I don't know why it's not working.

In a view, I put this code below:

<script type="text/javascript">
  google.load("visualization", "1", {packages:["corechart"]});
  google.setOnLoadCallback(drawChart);
  function drawChart() {
    var data = google.visualization.arrayToDataTable([
      ['Task', 'Hours per Day'],
      ['Work',     11],
      ['Eat',      2],
      ['Commute',  2],
      ['Watch TV', 2],
      ['Sleep',    7]
    ]);

    var options = {
      title: 'My Daily Activities'
    };

    var chart = new google.visualization.PieChart(document.getElementById('piechart'));
    chart.draw(data, options);
  }
</script>

<div id="piechart" style="width: 900px; height: 500px;"></div>

This show the graph correctly, but I if I pass a variable, didn't work, like that:

<% @test = [
      ['Task', 'Hours per Day'],
      ['Work',     11],
      ['Eat',      2],
      ['Commute',  2],
      ['Watch TV', 2],
      ['Sleep',    7]
    ] %>

<script type="text/javascript">
  google.load("visualization", "1", {packages:["corechart"]});
  google.setOnLoadCallback(drawChart);
  function drawChart() {
    var data = google.visualization.arrayToDataTable(<%= @test %>);

    var options = {
      title: 'My Daily Activities'
    };

    var chart = new google.visualization.PieChart(document.getElementById('piechart'));
    chart.draw(data, options);
  }
</script>

<div id="piechart" style="width: 900px; height: 500px;"></div>

This code don't show nothing, why?

Ps1: Sorry for English, I'm learning yet =]

Answer 1

this-

<% @test = [
          ['Task', 'Hours per Day'],
          ['Work',     11],
          ['Eat',      2],
          ['Commute',  2],
          ['Watch TV', 2],
          ['Sleep',    7]
        ] %>

just outputs as text into the html

if the variable is coming from the controller then;

<script type="text/javascript">
      var test = <%= @test %>
      google.load("visualization", "1", {packages:["corechart"]});
      google.setOnLoadCallback(drawChart);
      function drawChart() {
        var data = google.visualization.arrayToDataTable(test);

        var options = {
          title: 'My Daily Activities'
        };

        var chart = new google.visualization.PieChart(document.getElementById('piechart'));
        chart.draw(data, options);
      }
    </script>