title: ECharts refresh on data change
body: <p>I'm currently working on an interactive chart which should calculate potential risk-factors of commercial project. I've been using Baidu ECharts for this, and got the graph working visually, but can't get the graph to update when data changes. </p>
  
  <p>The data comes from an external questionnaire, which uses radiobuttons for the values and a checkbox to turn the whole set on and off. </p>
  
  <pre><code> &lt;input type="checkbox" id="GPEbool" value="true"&gt; Example Question 1&lt;/h4&gt;
      &lt;form action=""&gt;
    &lt;input type="radio" id="polishedness" value="1"&gt; Idea&lt;br&gt;
    &lt;input type="radio" id="polishedness" value="1"&gt; Concept&lt;br&gt;
    &lt;input type="radio" id="polishedness" value="2"&gt; Mockup&lt;br&gt;
    &lt;input type="radio" id="polishedness" value="5"&gt; Prototype&lt;br&gt;
    &lt;input type="radio" id="polishedness" value="7"&gt; Playable&lt;br&gt;
    &lt;input type="radio" id="polishedness" value="15"&gt; Polish&lt;br&gt;
    &lt;input type="radio" id="polishedness" value="30"&gt; Finished&lt;br&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>Now, the problem is getting the data into the graph. It gets the initially selected value right (when adding "checked" to one of them), but won't update after that. </p>
  
  <pre><code>data: [{ value: $('input[name=polishedness]:checked').val(), name: 'Design'}]
  </code></pre>
  
  <p>I've tried calling the refresh function whenever something changes, but it'll return refresh is not a function. I'm really at loss, and the Chinese documentation doesn't help me much :)</p>
  
  <p>Any suggestions? Thanks in advance!</p>