title: how to get the radial gradient to start from the centre of the pie chart?
body: <p>In <a href="http://jsfiddle.net/rdesai/duqvLndh/1/" rel="nofollow">my pie chart with grid lines</a>, I have integrated a radial gradient. The problem is that it there is a gradient for every pie. I actually want a gradient which is common and it originates from the center of the pie chart.</p>
  
  <p>I tried:</p>
  
  <pre><code>var arc = d3.svg.arc()
  .attr('fill', 'url(#gradient)')
  .outerRadius(function(d) { return 50 + (radius - 50) * d.data.percent / 100; })
  .innerRadius(20);
  </code></pre>
  
  <p>but it didnt help.</p>
  
  <p>How to get the radial gradient to start from the centre of the pie chart?</p>
  
  <p><a href="http://jsfiddle.net/rdesai/duqvLndh/1/" rel="nofollow">jsFiddle</a></p>