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freeCodeCamp/curriculum/challenges/english/04-data-visualization/data-visualization-with-d3/add-labels-to-d3-elements.md
Nicholas Carrigan (he/him) 16e420021c chore: audit data visualisation challenges (#41336)
* chore(learn): audit d3 projects

* chore: audit data vis

* chore: audit json apis

* Update curriculum/challenges/english/04-data-visualization/data-visualization-projects/visualize-data-with-a-scatterplot-graph.md

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Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com>
Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com>
2021-03-05 12:25:29 -07:00

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---
id: 587d7faa367417b2b2512bd2
title: Add Labels to D3 Elements
challengeType: 6
forumTopicId: 301476
dashedName: add-labels-to-d3-elements
---
# --description--
D3 lets you label a graph element, such as a bar, using the SVG `text` element.
Like the `rect` element, a `text` element needs to have `x` and `y` attributes, to place it on the SVG canvas. It also needs to access the data to display those values.
D3 gives you a high level of control over how you label your bars.
# --instructions--
The code in the editor already binds the data to each new `text` element. First, append `text` nodes to the `svg`. Next, add attributes for the `x` and `y` coordinates. They should be calculated the same way as the `rect` ones, except the `y` value for the `text` should make the label sit 3 units higher than the bar. Finally, use the D3 `text()` method to set the label equal to the data point value.
**Note:** For the label to sit higher than the bar, decide if the `y` value for the `text` should be 3 greater or 3 less than the `y` value for the bar.
# --hints--
The first `text` element should have a label of `12` and a `y` value of `61`.
```js
assert($('text').eq(0).text() == '12' && $('text').eq(0).attr('y') == '61');
```
The second `text` element should have a label of `31` and a `y` value of `4`.
```js
assert($('text').eq(1).text() == '31' && $('text').eq(1).attr('y') == '4');
```
The third `text` element should have a label of `22` and a `y` value of `31`.
```js
assert($('text').eq(2).text() == '22' && $('text').eq(2).attr('y') == '31');
```
The fourth `text` element should have a label of `17` and a `y` value of `46`.
```js
assert($('text').eq(3).text() == '17' && $('text').eq(3).attr('y') == '46');
```
The fifth `text` element should have a label of `25` and a `y` value of `22`.
```js
assert($('text').eq(4).text() == '25' && $('text').eq(4).attr('y') == '22');
```
The sixth `text` element should have a label of `18` and a `y` value of `43`.
```js
assert($('text').eq(5).text() == '18' && $('text').eq(5).attr('y') == '43');
```
The seventh `text` element should have a label of `29` and a `y` value of `10`.
```js
assert($('text').eq(6).text() == '29' && $('text').eq(6).attr('y') == '10');
```
The eighth `text` element should have a label of `14` and a `y` value of `55`.
```js
assert($('text').eq(7).text() == '14' && $('text').eq(7).attr('y') == '55');
```
The ninth `text` element should have a label of `9` and a `y` value of `70`.
```js
assert($('text').eq(8).text() == '9' && $('text').eq(8).attr('y') == '70');
```
# --seed--
## --seed-contents--
```html
<body>
<script>
const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];
const w = 500;
const h = 100;
const svg = d3.select("body")
.append("svg")
.attr("width", w)
.attr("height", h);
svg.selectAll("rect")
.data(dataset)
.enter()
.append("rect")
.attr("x", (d, i) => i * 30)
.attr("y", (d, i) => h - 3 * d)
.attr("width", 25)
.attr("height", (d, i) => 3 * d)
.attr("fill", "navy");
svg.selectAll("text")
.data(dataset)
.enter()
// Add your code below this line
// Add your code above this line
</script>
<body>
```
# --solutions--
```html
<body>
<script>
const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];
const w = 500;
const h = 100;
const svg = d3.select("body")
.append("svg")
.attr("width", w)
.attr("height", h);
svg.selectAll("rect")
.data(dataset)
.enter()
.append("rect")
.attr("x", (d, i) => i * 30)
.attr("y", (d, i) => h - 3 * d)
.attr("width", 25)
.attr("height", (d, i) => 3 * d)
.attr("fill", "navy");
svg.selectAll("text")
.data(dataset)
.enter()
.append("text")
.attr("x", (d, i) => i * 30)
.attr("y", (d, i) => h - (3 * d) - 3)
.text((d) => d)
</script>
<body>
```