enjalot · September 8, 2011 15:15 · nicolas-amabile · Oct 21, 2014 · bethrobson · Aug 14, 2015
diff --git a/index.html b/index.html
 <!DOCTYPE html>
 <html>
  <head>    
    <meta http-equiv="Content-type" content="text/html; charset=utf-8">
    <title>Testing Pie Chart</title>
    <script type="text/javascript" src="http://mbostock.github.com/d3/d3.js?2.1.3"></script>
    <script type="text/javascript" src="http://mbostock.github.com/d3/d3.geom.js?2.1.3"></script>
    <script type="text/javascript" src="http://mbostock.github.com/d3/d3.layout.js?2.1.3"></script>

    <style type="text/css">
        .slice text {
            font-size: 16pt;
            font-family: Arial;
        }   
    </style>
  </head>
  <body>
    <script type="text/javascript">

    var w = 300,                        //width
    h = 300,                            //height
    r = 100,                            //radius
    color = d3.scale.category20c();     //builtin range of colors

    data = [{"label":"one", "value":20}, 
            {"label":"two", "value":50}, 
            {"label":"three", "value":30}];
    
    var vis = d3.select("body")
        .append("svg:svg")              //create the SVG element inside the <body>
        .data([data])                   //associate our data with the document
            .attr("width", w)           //set the width and height of our visualization (these will be attributes of the <svg> tag
            .attr("height", h)
        .append("svg:g")                //make a group to hold our pie chart
            .attr("transform", "translate(" + r + "," + r + ")")    //move the center of the pie chart from 0, 0 to radius, radius

    var arc = d3.svg.arc()              //this will create <path> elements for us using arc data
        .outerRadius(r);

    var pie = d3.layout.pie()           //this will create arc data for us given a list of values
        .value(function(d) { return d.value; });    //we must tell it out to access the value of each element in our data array

    var arcs = vis.selectAll("g.slice")     //this selects all <g> elements with class slice (there aren't any yet)
        .data(pie)                          //associate the generated pie data (an array of arcs, each having startAngle, endAngle and value properties) 
        .enter()                            //this will create <g> elements for every "extra" data element that should be associated with a selection. The result is creating a <g> for every object in the data array
            .append("svg:g")                //create a group to hold each slice (we will have a <path> and a <text> element associated with each slice)
                .attr("class", "slice");    //allow us to style things in the slices (like text)

        arcs.append("svg:path")
                .attr("fill", function(d, i) { return color(i); } ) //set the color for each slice to be chosen from the color function defined above
                .attr("d", arc);                                    //this creates the actual SVG path using the associated data (pie) with the arc drawing function

        arcs.append("svg:text")                                     //add a label to each slice
                .attr("transform", function(d) {                    //set the label's origin to the center of the arc
                //we have to make sure to set these before calling arc.centroid
                d.innerRadius = 0;
                d.outerRadius = r;
                return "translate(" + arc.centroid(d) + ")";        //this gives us a pair of coordinates like [50, 50]
            })
            .attr("text-anchor", "middle")                          //center the text on it's origin
            .text(function(d, i) { return data[i].label; });        //get the label from our original data array
        
    </script>
  </body>
 </html>
	<!DOCTYPE html>
	<html>
	<head>
	<meta http-equiv="Content-type" content="text/html; charset=utf-8">
	<title>Testing Pie Chart</title>
	<script type="text/javascript" src="http://mbostock.github.com/d3/d3.js?2.1.3"></script>
	<script type="text/javascript" src="http://mbostock.github.com/d3/d3.geom.js?2.1.3"></script>
	<script type="text/javascript" src="http://mbostock.github.com/d3/d3.layout.js?2.1.3"></script>

	<style type="text/css">
	.slice text {
	font-size: 16pt;
	font-family: Arial;
	}
	</style>
	</head>
	<body>
	<script type="text/javascript">

	var w = 300, //width
	h = 300, //height
	r = 100, //radius
	color = d3.scale.category20c(); //builtin range of colors

	data = [{"label":"one", "value":20},
	{"label":"two", "value":50},
	{"label":"three", "value":30}];

	var vis = d3.select("body")
	.append("svg:svg") //create the SVG element inside the <body>
	.data([data]) //associate our data with the document
	.attr("width", w) //set the width and height of our visualization (these will be attributes of the <svg> tag
	.attr("height", h)
	.append("svg:g") //make a group to hold our pie chart
	.attr("transform", "translate(" + r + "," + r + ")") //move the center of the pie chart from 0, 0 to radius, radius

	var arc = d3.svg.arc() //this will create <path> elements for us using arc data
	.outerRadius(r);

	var pie = d3.layout.pie() //this will create arc data for us given a list of values
	.value(function(d) { return d.value; }); //we must tell it out to access the value of each element in our data array

	var arcs = vis.selectAll("g.slice") //this selects all <g> elements with class slice (there aren't any yet)
	.data(pie) //associate the generated pie data (an array of arcs, each having startAngle, endAngle and value properties)
	.enter() //this will create <g> elements for every "extra" data element that should be associated with a selection. The result is creating a <g> for every object in the data array
	.append("svg:g") //create a group to hold each slice (we will have a <path> and a <text> element associated with each slice)
	.attr("class", "slice"); //allow us to style things in the slices (like text)

	arcs.append("svg:path")
	.attr("fill", function(d, i) { return color(i); } ) //set the color for each slice to be chosen from the color function defined above
	.attr("d", arc); //this creates the actual SVG path using the associated data (pie) with the arc drawing function

	arcs.append("svg:text") //add a label to each slice
	.attr("transform", function(d) { //set the label's origin to the center of the arc
	//we have to make sure to set these before calling arc.centroid
	d.innerRadius = 0;
	d.outerRadius = r;
	return "translate(" + arc.centroid(d) + ")"; //this gives us a pair of coordinates like [50, 50]
	})
	.attr("text-anchor", "middle") //center the text on it's origin
	.text(function(d, i) { return data[i].label; }); //get the label from our original data array

	</script>
	</body>
	</html>