title: D3.js donut chart... arc.centroid(d) is not influenced by d.innerRadius and d.outerRadius
body: <p>I'm creating a donut (or Piechart) and I want to place the labels just outside the area.
  I've created a fiddle <a href="http://jsfiddle.net/VeeTee/mA3V7/" rel="nofollow">http://jsfiddle.net/VeeTee/mA3V7/</a> for it.</p>
  
  <pre><code>arcs.append("svg:text")
      .attr("transform", function(d) {
          //this is where I want to make a translation to the outside border
          d.innerRadius = radius;
          d.outerRadius = height/2;
          return "translate(" + arc.centroid(d) +")";
      })
      .attr("dy", ".35em")
      .attr("text-anchor", "middle")
      .text(function(d, i) { return d.value.toFixed(2); });
  </code></pre>
  
  <p>arc.centroid(d) -> is always giving the same result (and therefore the same translation)</p>