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
challengeType: 6
forumTopicId: 301477
dashedName: add-labels-to-scatter-plot-circles
---
# --description--
You can add text to create labels for the points in a scatter plot.
The goal is to display the comma-separated values for the first (`x`) and second (`y`) fields of each item in `dataset`.
The `text` nodes need `x` and `y` attributes to position it on the SVG canvas. In this challenge, the `y` value (which determines height) can use the same value that the `circle` uses for its `cy` attribute. The `x` value can be slightly larger than the `cx` value of the `circle`, so the label is visible. This will push the label to the right of the plotted point.
# --instructions--
Label each point on the scatter plot using the `text` elements. The text of the label should be the two values separated by a comma and a space. For example, the label for the first point is "34, 78". Set the `x` attribute so it's 5 units more than the value you used for the `cx` attribute on the `circle`. Set the `y` attribute the same way that's used for the `cy` value on the `circle`.
# --hints--
Your code should have 10 `text` elements.
```js
assert($('text').length == 10);
```
The first label should have text of "34, 78", an `x` value of 39, and a `y` value of 422.
```js
assert(
$('text').eq(0).text() == '34, 78' &&
$('text').eq(0).attr('x') == '39' &&
$('text').eq(0).attr('y') == '422'
);
```
The second label should have text of "109, 280", an `x` value of 114, and a `y` value of 220.
```js
assert(
$('text').eq(1).text() == '109, 280' &&
$('text').eq(1).attr('x') == '114' &&
$('text').eq(1).attr('y') == '220'
);
```
The third label should have text of "310, 120", an `x` value of 315, and a `y` value of 380.
```js
assert(
$('text').eq(2).text() == '310, 120' &&
$('text').eq(2).attr('x') == '315' &&
$('text').eq(2).attr('y') == '380'
);
```
The fourth label should have text of "79, 411", an `x` value of 84, and a `y` value of 89.
```js
assert(
$('text').eq(3).text() == '79, 411' &&
$('text').eq(3).attr('x') == '84' &&
$('text').eq(3).attr('y') == '89'
);
```
The fifth label should have text of "420, 220", an `x` value of 425, and a `y` value of 280.
```js
assert(
$('text').eq(4).text() == '420, 220' &&
$('text').eq(4).attr('x') == '425' &&
$('text').eq(4).attr('y') == '280'
);
```
The sixth label should have text of "233, 145", an `x` value of 238, and a `y` value of 355.
```js
assert(
$('text').eq(5).text() == '233, 145' &&
$('text').eq(5).attr('x') == '238' &&
$('text').eq(5).attr('y') == '355'
);
```
The seventh label should have text of "333, 96", an `x` value of 338, and a `y` value of 404.
```js
assert(
$('text').eq(6).text() == '333, 96' &&
$('text').eq(6).attr('x') == '338' &&
$('text').eq(6).attr('y') == '404'
);
```
The eighth label should have text of "222, 333", an `x` value of 227, and a `y` value of 167.
```js
assert(
$('text').eq(7).text() == '222, 333' &&
$('text').eq(7).attr('x') == '227' &&
$('text').eq(7).attr('y') == '167'
);
```
The ninth label should have text of "78, 320", an `x` value of 83, and a `y` value of 180.
```js
assert(
$('text').eq(8).text() == '78, 320' &&
$('text').eq(8).attr('x') == '83' &&
$('text').eq(8).attr('y') == '180'
);
```
The tenth label should have text of "21, 123", an `x` value of 26, and a `y` value of 377.
```js
assert(
$('text').eq(9).text() == '21, 123' &&
$('text').eq(9).attr('x') == '26' &&
$('text').eq(9).attr('y') == '377'
);
```
# --seed--
## --seed-contents--
```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>
```
# --solutions--
```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")
.attr("x", (d) => d[0] + 5)
.attr("y", (d) => h - d[1])
.text((d) => (d[0] + ", " + d[1]))
</script>
</body>
```