title: How to format my json data for stack column chart in HighCharts
body: <p>Here is my json data</p>
  
  <pre><code>var data = [
      {"unit":"a", "status":"Stopped / Idle", "val":21.2022222222222222},
      {"unit":"a", "status":"Working", "val":53.3066666666666667},
      {"unit":"a", "status":"Headland Turning", "val":0.04694444444444444444},
      {"unit":"a", "status":"Transport", "val":5.1425000000000000},
      {"unit":"b", "status":"Stopped / Idle", "val":334.7358333333333333},
      {"unit":"b", "status":"Working", "val":212.6386111111111111},
      {"unit":"b", "status":"Headland Turning", "val":26.2955555555555556},
      {"unit":"b", "status":"Transport", "val":0.00444444444444444444}
  ];
  </code></pre>
  
  <p><code>unit</code> is the category</p>
  
  <p>I want the data could be formatted in the following way so that I can plug in to <code>series</code> option in HighCharts: </p>
  
  <pre><code>series: [{
                  name: 'Stopped / Idle',
                  data: [21.2022222222222222, 334.7358333333333333]},
              {
                  name: 'Working',
                  data: [53.3066666666666667, 212.6386111111111111]},
              {
                  name: 'Headland Turning',
                  data: [0.04694444444444444444, 26.2955555555555556]},
              {
                  name: 'Transport',
                  data: [5.1425000000000000, 0.00444444444444444444]}]
          });
  </code></pre>
  
  <p>Thank you. </p>