使用 d3.js 制作分组条形图答案

【问题标题】：Making a grouped bar chart using d3.js使用 d3.js 制作分组条形图
【发布时间】：2017-12-25 22:56:29
【问题描述】：

我是 d3.js 的新手，我发现很难创建分组条形图，但我尝试了一些似乎不正确的方法。我想要 x 轴上的月份和 y 轴上的组数（火星和木星）。类似于 dis Link。

var svg = d3.select("svg"),
margin = {top: 20, right: 20, bottom: 30, left: 40},
width = +svg.attr("width") - margin.left - margin.right, height = +svg.attr("height") - margin.top - margin.bottom;

var x = d3.scaleBand().rangeRound([0,
width]).padding(0.1),
		y = d3.scaleLinear().rangeRound([height, 0]);

var g = svg.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")");

var data = [
        {"Group":"Mars","count":10,"months":"June"},
        {"Group":"Jupiter","count":50,"months":"June"},
	{"Group":"Mars","count":70,"months":"July"},
        {"Group":"Jupiter","count":60,"months":"July"}];


     var ymaxdomain=d3.max(d,function(d){return d.count;});
			  x.domain(d.map(function(d) {return d.months}));
				y.domain([0,ymaxdomain]);

   
		
		 var x1=d3.scaleBand().rangeRound([0, x.bandwidth()]);
         x1.domain(d.map(function(d) {return d.months;}));

   

    g.selectAll(".bar")
        .data(data)
        .enter().append("rect")
        .attr("x", function(d,i) {console.log(d,i); return (x(d.months))}
        .attr("y", function(d) {return y(d.count); })
        .attr("width",x1.bandwidth())
        .attr("height", function(d) { return height - y(d.count); })
				
		g.append("g")
			.attr("class", "axis")
			.attr("transform", "translate(0," + height + ")")
			.call(d3.axisBottom(x));


		g.append("g")
			.attr("class", "axis")
			.call(d3.axisLeft(y).ticks(null, "s"))
			.append("text")
			.attr("x", 2)
			.attr("y", y(y.ticks().pop()) + 0.5)
			.attr("dy", "0.32em")
			.attr("fill", "#000")
			.attr("font-weight", "bold")
			.attr("text-anchor", "start")
			.text("count");

<style>

.bar {
  fill: steelblue;
  stroke:black
}

</style>

<!DOCTYPE html>
<svg width="600" height="600"></svg>
<body><script src="//d3js.org/d3.v4.min.js"></script></body>

【问题讨论】：

标签： javascript d3.js bar-chart

【解决方案1】：

要创建分组条形图，您必须为 x 位置设置 2 个比例：

var x = d3.scaleBand().rangeRound([0, width])
  .padding(0.1);

var x1 = d3.scaleBand()
  .rangeRound([0, x.bandwidth()])
  .padding(0.05);

然后，您使用第一个比例附加组...

var groups = g.selectAll(null)
  .data(data)
  .enter()
  .append("g")
  .attr("transform", function(d) {
    return "translate(" + x(d.months) + ",0)";
  })

...并且，在每个组内，您使用第二个比例附加矩形。

这里是演示：

var svg = d3.select("svg"),
  margin = {
    top: 20,
    right: 20,
    bottom: 30,
    left: 40
  },
  width = +svg.attr("width") - margin.left - margin.right,
  height = +svg.attr("height") - margin.top - margin.bottom;

var color = d3.scaleOrdinal(d3.schemeCategory10);

var x = d3.scaleBand().rangeRound([0, width])
  .padding(0.1),
  y = d3.scaleLinear().rangeRound([height, 0]);

var g = svg.append("g")
  .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

var data = [{
  "Group": "Mars",
  "count": 10,
  "months": "June"
}, {
  "Group": "Jupiter",
  "count": 50,
  "months": "June"
}, {
  "Group": "Mars",
  "count": 70,
  "months": "July"
}, {
  "Group": "Jupiter",
  "count": 60,
  "months": "July"
}];

var ymaxdomain = d3.max(data, function(d) {
  return d.count;
});
x.domain(data.map(function(d) {
  return d.months
}));
y.domain([0, ymaxdomain]);

var x1 = d3.scaleBand()
  .rangeRound([0, x.bandwidth()])
  .padding(0.05)
  .domain(data.map(function(d) {
    return d.Group;
  }));

color.domain(data.map(function(d) {
  return d.Group;
}));

var groups = g.selectAll(null)
  .data(data)
  .enter()
  .append("g")
  .attr("transform", function(d) {
    return "translate(" + x(d.months) + ",0)";
  })

var bars = groups.selectAll(null)
  .data(function(d) {
    return [d]
  })
  .enter()
  .append("rect")
  .attr("x", function(d, i) {
    return x1(d.Group)
  })
  .attr("y", function(d) {
    return y(d.count);
  })
  .attr("width", x1.bandwidth())
  .attr("height", function(d) {
    return height - y(d.count);
  })
  .attr("fill", function(d) {
    return color(d.Group)
  })

g.append("g")
  .attr("class", "axis")
  .attr("transform", "translate(0," + height + ")")
  .call(d3.axisBottom(x));

g.append("g")
  .attr("class", "axis")
  .call(d3.axisLeft(y).ticks(null, "s"))
  .append("text")
  .attr("x", 2)
  .attr("y", y(y.ticks().pop()) + 0.5)
  .attr("dy", "0.32em")
  .attr("fill", "#000")
  .attr("font-weight", "bold")
  .attr("text-anchor", "start")
  .text("count");

.bar {
  fill: steelblue;
  stroke: black
}

<svg width="600" height="600"></svg>
<script src="//d3js.org/d3.v4.min.js"></script>

【讨论】：

我非常感谢您的帮助。非常感谢！:)@Gerardo Furtado
我正在学习 d3js .... 这里你调用函数 x 并传递一个 arg d.months... 你在哪里使用它在 var x = .....