ring chart clockwise transition

a ring chart (or a donut chart if you are hungry) that animates into existence.

this answer http://stackoverflow.com/questions/20501067/animating-d3-donut-chart-on-load had just the tween and transition code examples needed to animate each slice in sequence.

Original README.md:

This is the code for Chapter 5, Figure 6 from D3.js in Action demonstrating how to make a donut chart using d3.layout.pie().

forked from emeeks's block: Ch. 5, Fig. 6 - D3.js in Action

forked from emeeks's block: Pie Transition Ch. 5 - D3.js in Action

<html>
<head>
  <title>ring chart clockwise transition</title>
  <meta charset="utf-8" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.16/d3.min.js" type="text/JavaScript"></script>
</head>
<style>
  svg {
    height: 500px;
    width: 960px;
    border: 0px solid gray;
  }
  
</style>
<body>

<div id="viz">
  <svg>
  </svg>
</div>
</body>
  <footer>
    
<script>
    d3.json("tweets.json",function(error,data) {dataViz(data.tweets)});
    
    function dataViz(incData) {
      
      var background = d3.select('svg')
      	.append('rect')
      	.classed('background', true)
      	.attr({
        	'x': 0,
        	'y': 0,
        	'height': 500,
        	'width': 960
      	})
      	.style('fill', 'white');
      
      nestedTweets = d3.nest()
      .key(function (el) {return el.user})
      .entries(incData);
		
    	var sunlight14 = [
				'#193556',
				'#42A5B3',  
				'#E3BA22',
				'#F2DA57',
				'#BD8F22',
				'#E6842A',
				'#F6B656',
				'#BA5F06',
				'#137B80',
				'#42A5B3',
				'#005D6E',
				'#8E6C8A',
				'#B396AD',
				'#684664'
			]
    	var colorScale = d3.scale.ordinal()
    		.range(sunlight14);

nestedTweets.forEach(function (el) {
        el.numTweets = el.values.length
        el.numFavorites = d3.sum(el.values, function (d) {return d.favorites.length});
        el.numRetweets = d3.sum(el.values, function (d) {return d.retweets.length});
      })
      
     	var pieChart = d3.layout.pie().sort(null);
     	pieChart.value(function(d) {return d.numRetweets});
     	newArc = d3.svg.arc();
     	newArc.outerRadius(200).innerRadius(170);

pieChartFavs = d3.layout.pie().sort(null);
     pieChartFavs.value(function(d) {return d.numFavorites});
      console.log('pieChartFavs', pieChartFavs);
      
      d3.select("svg")
      .append("g")
      .attr("transform","translate(480,250)")
      .selectAll("path")
      .data(pieChartFavs(nestedTweets), function(d) {return d.data.key})
      .enter()
      .append("path")
      	.attr("d", newArc)
      		.style("fill", function(d, i) {return colorScale(i)})
      		.style("opacity", 0)
      		.style("stroke", "none")
      		.style("stroke-width", "2px")
      		.each(function(d) { this._current = d; });

animate();
      
      d3.select('rect.background').on('click', click);
      
      function click() {
        d3.selectAll('path')
          .transition()
          .duration(0)
          .style('opacity', 0)
        .call(null, animate())  
      }
      
      function arcTween(a) {
        var i = d3.interpolate(this._current, a);
        this._current = i(0);
      return function(t) {
      return newArc(i(t));
      };
       
    }
    
    }

</script>
  </footer>

</html>

https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.16/d3.min.js