freeCodeCamp/curriculum/challenges/chinese/04-data-visualization/data-visualization-with-d3/add-labels-to-scatter-plot-...

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---
id: 587d7fab367417b2b2512bd9
title: Add Labels to Scatter Plot Circles
required:
- src: 'https://cdnjs.cloudflare.com/ajax/libs/d3/4.3.0/d3.min.js'
challengeType: 6
videoUrl: ''
localeTitle: 添加标签以分散绘图圆圈
---
## Description
<section id="description">您可以添加文本以在散点图中为点创建标签。目标是显示<code>dataset</code>每个项目的第一个( <code>x</code> )和第二个( <code>y</code> )字段的逗号分隔值。 <code>text</code>节点需要<code>x</code><code>y</code>属性才能将其放置在SVG画布上。在此挑战中 <code>y</code>值(确定高度)可以使用<code>circle</code>用于其<code>cy</code>属性的相同值。 <code>x</code>值可能略大于<code>circle</code><code>cx</code>值,因此标签可见。这会将标签推到绘图点的右侧。 </section>
## Instructions
<section id="instructions">使用<code>text</code>元素标记散点图上的每个点。标签的文本应该是用逗号和空格分隔的两个值。例如第一个点的标签是“34,78”。设置<code>x</code>属性,使其比<code>circle</code><code>cx</code>属性使用的值多5个单位。设置<code>y</code>属性的方式与<code>circle</code>上的<code>cy</code>值相同。 </section>
## Tests
<section id='tests'>
```yml
tests:
- text: 您的代码应该有10个<code>text</code>元素。
testString: 'assert($("text").length == 10, "Your code should have 10 <code>text</code> elements.");'
- text: '第一个标签的文本应为“34,78” <code>x</code>值为39 <code>y</code>值为422。'
testString: 'assert($("text").eq(0).text() == "34, 78" && $("text").eq(0).attr("x") == "39" && $("text").eq(0).attr("y") == "422", "The first label should have text of "34, 78", an <code>x</code> value of 39, and a <code>y</code> value of 422.");'
- text: '第二个标签的文本应为“109,280” <code>x</code>值为114 <code>y</code>值为220。'
testString: 'assert($("text").eq(1).text() == "109, 280" && $("text").eq(1).attr("x") == "114" && $("text").eq(1).attr("y") == "220", "The second label should have text of "109, 280", an <code>x</code> value of 114, and a <code>y</code> value of 220.");'
- text: '第三个标签的文本应为“310,120” <code>x</code>值为315 <code>y</code>值为380。'
testString: 'assert($("text").eq(2).text() == "310, 120" && $("text").eq(2).attr("x") == "315" && $("text").eq(2).attr("y") == "380", "The third label should have text of "310, 120", an <code>x</code> value of 315, and a <code>y</code> value of 380.");'
- text: '第四个标签的文本应为“79,411” <code>x</code>值为84 <code>y</code>值为89。'
testString: 'assert($("text").eq(3).text() == "79, 411" && $("text").eq(3).attr("x") == "84" && $("text").eq(3).attr("y") == "89", "The fourth label should have text of "79, 411", an <code>x</code> value of 84, and a <code>y</code> value of 89.");'
- text: '第五个标签的文本应为“420,220” <code>x</code>值为425 <code>y</code>值为280。'
testString: 'assert($("text").eq(4).text() == "420, 220" && $("text").eq(4).attr("x") == "425" && $("text").eq(4).attr("y") == "280", "The fifth label should have text of "420, 220", an <code>x</code> value of 425, and a <code>y</code> value of 280.");'
- text: '第六个标签的文本应为“233,145” <code>x</code>值为238 <code>y</code>值为355。'
testString: 'assert($("text").eq(5).text() == "233, 145" && $("text").eq(5).attr("x") == "238" && $("text").eq(5).attr("y") == "355", "The sixth label should have text of "233, 145", an <code>x</code> value of 238, and a <code>y</code> value of 355.");'
- text: '第七个标签的文本应为“333,96” <code>x</code>值为338 <code>y</code>值为404。'
testString: 'assert($("text").eq(6).text() == "333, 96" && $("text").eq(6).attr("x") == "338" && $("text").eq(6).attr("y") == "404", "The seventh label should have text of "333, 96", an <code>x</code> value of 338, and a <code>y</code> value of 404.");'
- text: '第八个标签的文本应为“222,333” <code>x</code>值为227 <code>y</code>值为167。'
testString: 'assert($("text").eq(7).text() == "222, 333" && $("text").eq(7).attr("x") == "227" && $("text").eq(7).attr("y") == "167", "The eighth label should have text of "222, 333", an <code>x</code> value of 227, and a <code>y</code> value of 167.");'
- text: '第九个标签的文本应为“78,320” <code>x</code>值为83 <code>y</code>值为180。'
testString: 'assert($("text").eq(8).text() == "78, 320" && $("text").eq(8).attr("x") == "83" && $("text").eq(8).attr("y") == "180", "The ninth label should have text of "78, 320", an <code>x</code> value of 83, and a <code>y</code> value of 180.");'
- text: '第十个标签的文本应为“21,123” <code>x</code>值为26 <code>y</code>值为377。'
testString: 'assert($("text").eq(9).text() == "21, 123" && $("text").eq(9).attr("x") == "26" && $("text").eq(9).attr("y") == "377", "The tenth label should have text of "21, 123", an <code>x</code> value of 26, and a <code>y</code> value of 377.");'
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='html-seed'>
```html
<body>
<script>
const dataset = [
[ 34, 78 ],
[ 109, 280 ],
[ 310, 120 ],
[ 79, 411 ],
[ 420, 220 ],
[ 233, 145 ],
[ 333, 96 ],
[ 222, 333 ],
[ 78, 320 ],
[ 21, 123 ]
];
const w = 500;
const h = 500;
const svg = d3.select("body")
.append("svg")
.attr("width", w)
.attr("height", h);
svg.selectAll("circle")
.data(dataset)
.enter()
.append("circle")
.attr("cx", (d, i) => d[0])
.attr("cy", (d, i) => h - d[1])
.attr("r", 5);
svg.selectAll("text")
.data(dataset)
.enter()
.append("text")
// Add your code below this line
// Add your code above this line
</script>
</body>
```
</div>
</section>
## Solution
<section id='solution'>
```js
// solution required
```
</section>