D3 v4 - piechart

D3.js ver.4 で作成した円グラフ

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge"/>
<title>D3 v4 - piechart</title>
<style>
#graph {
    width: 900px;
    height: 500px;
}
</style>
</head>

<body>
<div id="graph"></div>    
        
<script src="//cdnjs.cloudflare.com/ajax/libs/d3/4.1.1/d3.min.js"></script>    
<script>
!(function(){
    "use strict"
    
    var width,height
    var chartWidth, chartHeight
    var margin
    var svg = d3.select("#graph").append("svg")
    var chartLayer = svg.append("g").classed("chartLayer", true)
    
    d3.csv("data.csv", cast,  main)
    
    function cast(d) {
        d.value = +d.value
        return d 
    }
    
    function main(data) {
        setSize(data)
        drawChart(data)    
    }
    
    function setSize(data) {
        width = document.querySelector("#graph").clientWidth
        height = document.querySelector("#graph").clientHeight
    
        margin = {top:40, left:0, bottom:40, right:0 }
        
        
        chartWidth = width - (margin.left+margin.right)
        chartHeight = height - (margin.top+margin.bottom)
        
        svg.attr("width", width).attr("height", height)
        
        
        chartLayer
            .attr("width", chartWidth)
            .attr("height", chartHeight)
            .attr("transform", "translate("+[margin.left, margin.top]+")")
            
            
    }
    
    function drawChart(data) {
        //pieチャート用のデータセットを生成する
        var arcs = d3.pie()
            .sort(null)
            .value(function(d) { return d.value; })
            (data)
        
        //パスジェネレーターを生成する    
        var arc = d3.arc()
            .outerRadius(chartHeight/2)
            .innerRadius(chartHeight/4)
            .padAngle(0.03)
            .cornerRadius(8)
            
        var pieG = chartLayer.selectAll("g")
            .data([data])
            .enter()
            .append("g")
            .attr("transform", "translate("+[chartWidth/2, chartHeight/2]+")")
        
        var block = pieG.selectAll(".arc")
            .data(arcs)
            
        var newBlock = block.enter().append("g").classed("arc", true)
            
        //円グラフ描画
        newBlock.append("path")
            .attr("d", arc)
            .attr("id", function(d, i) { return "arc-" + i })
            .attr("stroke", "gray")
            .attr("fill", function(d,i){ return d3.interpolateCool(Math.random()) })
        
        //ラベル表示
        newBlock.append("text")
            .attr("dx", 55)
            .attr("dy", -5)
            .append("textPath")
            .attr("xlink:href", function(d, i) { return "#arc-" + i; })
            .text(function(d) { console.log(d);return d.data.name })
    }
}());
</script>    
</body>
</html>

https://cdnjs.cloudflare.com/ajax/libs/d3/4.1.1/d3.min.js