//隨機生成資料
var rand = d3.random.normal(0,25)
var dataset = [];
for (var i = 0;i <100;i++){
    dataset.push(rand());
}

一、直方圖資料轉換函式：

//資料轉換
var bin_num = 15
var histogram=d3.layout.histogram()
    .range([-50,50]) //區間範圍
    .bins(bin_num) //分隔數
    .frequency(true)//true:統計個數；false:統計概率
var data = histogram(dataset);
console.log (data)
 

var svg = d3.select("body").append("svg")
    .attr("width",600)
    .attr("height",600)
var color = d3.scale.category20();

var max_height = 400,
    rect_step = 30,//直方圖間距
    heights = [];
for (var i = 0;i<data.length;i++){
    heights.push(data[i].y)
}
var scale_y = d3.scale.linear()
    .domain([d3.min(heights),d3.max(heights)])
    .range([0,max_height])
 

var graphics = svg.append("g")
    .attr("transform","translate(30,20)");

graphics.selectAll("rect")
    .data(data)
    .enter()
    .append("rect")
    .attr("y",function(d,i){
        return 300
    })//動畫開始的y值
    .attr("height",0)//動畫開始高度
    .attr("fill","red")//動畫開始顏色
    .transition()//實現動態效果函式
    .duration(3000)//指定整個轉變持續的時間，單位為毫秒
    .ease("bounce")//指定轉變的方式,linear:普通的線性變化;circle:慢慢地到達變換的最終狀態;elastic帶有彈跳的到達最終狀態;bounce在最終狀態處彈跳幾次.
    .delay(function(d,i){
        return 200*i;
    })//指定延遲的時間，表示一定時間後才開始轉變，單位同樣為毫秒
    .attr("x",function(d,i){return i*rect_step})
    .attr("y",function(d,i){return max_height - scale_y(d.y)})
    .attr("width",function(d,i){return rect_step-2})
    .attr("height", function (d) {
        return scale_y(d.y)
    })
    .attr("fill",color)
 

<pre name="code" class="javascript">//新增滑鼠事件
var rect = graphics.selectAll("rect")
    .on("mouseover",function(d,i){
        d3.select(this)
            .attr("fill","yellow")
    })
    .on("mouseout",function(d,i){
        d3.select(this)
            .attr("fill",color)
    })

//繪製箭頭
var defs = svg.append("defs")
var arrowMarker = defs.append("marker")
    .attr("id","arrow")
    .attr("markerUnits","strokeWidth")
    .attr("markerWidth",30)
    .attr("markerHeight",30)
    .attr("viewBox","0 0 20 20")
    .attr("refX",6)
    .attr("refY",6)
    .attr("orient","auto")
var arrow_path = "M2,2 L10,6 L2,10 L6,6 L2,2";
arrowMarker.append("path")
    .attr("d",arrow_path)
    .attr("fill","#000")
//繪製橫軸、縱軸並新增箭頭
graphics.append("line")
    .attr("stroke","black")
    .attr("stroke-width","1px")
    .attr("x1",0)
    .attr("y1",max_height)
    .attr("x2",data.length*rect_step)
    .attr("y2",max_height)
    .attr("marker-end","url(#arrow)")
graphics.append("line")
    .attr("stroke","black")
    .attr("stroke-width","1px")
    .attr("x1",0)
    .attr("y1",max_height)
    .attr("x2",0)
    .attr("y2",0)
    .attr("marker-end","url(#arrow)")
//繪製座標軸的分隔符直線
graphics.selectAll(".linetick")
    .data(data)
    .enter()
    .append("line")
    .attr("stroke","black")
    .attr("x1",function(d,i){return i*rect_step+rect_step/2})
    .attr("y1",max_height)
    .attr("x2",function(d,i){
        return i*rect_step+rect_step/2
    })
    .attr("y2",max_height+5)

graphics.selectAll("text")
    .data(data)
    .enter()
    .append("text")
    .attr("font-size","10px")
    .attr("x",function(d,i){
        return i * rect_step;
    })
    .attr("y", function(d,i){
        return max_height;
    })
    .attr("dx",rect_step/2 - 8)
    .attr("dy","15px")
    .text(function(d){
        return Math.floor(d.x);
    });