anchor.diff:  function change(data) {
   
     function show_percent(d) {
  +    if (animating) return;
       svg.select(".percent").select("text")
         .text(percent(d));
   
  
positive.code: var key = function(d){ return d.data.category; };
  
    function hide_percent() {
      svg.select(".percent").select("text")
        .text("");
  
  
negative.code:     .style("text-anchor", "middle")
      .style("font-size", "1.9em");
  
  var color = d3.scale.category20();
  
  var pie = d3.layout.pie()
  