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---
id: 587d7fa8367417b2b2512bc9
title: Update the Height of an Element Dynamically
challengeType: 6
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forumTopicId: 301493
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dashedName: update-the-height-of-an-element-dynamically
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---
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# --description--
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The previous challenges covered how to display data from an array and how to add CSS classes. You can combine these lessons to create a simple bar chart. There are two steps to this:
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1) Create a `div` for each data point in the array
2) Give each `div` a dynamic height, using a callback function in the `style()` method that sets height equal to the data value
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Recall the format to set a style using a callback function:
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```js
selection.style("cssProperty", (d) => d)
```
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# --instructions--
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Add the `style()` method to the code in the editor to set the `height` property for each element. Use a callback function to return the value of the data point with the string `px` added to it.
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# --hints--
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The first `div` should have a `height` of `12` pixels.
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```js
assert($('div').eq(0)[0].style.height === '12px');
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```
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The second `div` should have a `height` of `31` pixels.
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```js
assert($('div').eq(1)[0].style.height === '31px');
```
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The third `div` should have a `height` of `22` pixels.
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```js
assert($('div').eq(2)[0].style.height === '22px');
```
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The fourth `div` should have a `height` of `17` pixels.
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```js
assert($('div').eq(3)[0].style.height === '17px');
```
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The fifth `div` should have a `height` of `25` pixels.
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```js
assert($('div').eq(4)[0].style.height === '25px');
```
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The sixth `div` should have a `height` of `18` pixels.
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```js
assert($('div').eq(5)[0].style.height === '18px');
```
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The seventh `div` should have a `height` of `29` pixels.
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```js
assert($('div').eq(6)[0].style.height === '29px');
```
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The eighth `div` should have a `height` of `14` pixels.
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```js
assert($('div').eq(7)[0].style.height === '14px');
```
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The ninth `div` should have a `height` of `9` pixels.
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```js
assert($('div').eq(8)[0].style.height === '9px');
```
# --seed--
## --seed-contents--
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```html
< style >
.bar {
width: 25px;
height: 100px;
display: inline-block;
background-color: blue;
}
< / style >
< body >
< script >
const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];
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d3.select("body").selectAll("div")
.data(dataset)
.enter()
.append("div")
.attr("class", "bar")
// Add your code below this line
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// Add your code above this line
< / script >
< / body >
```
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# --solutions--
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```html
< style >
.bar {
width: 25px;
height: 100px;
display: inline-block;
background-color: blue;
}
< / style >
< body >
< script >
const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];
d3.select("body").selectAll("div")
.data(dataset)
.enter()
.append("div")
.attr("class", "bar")
.style('height', d => `${d}px` )
< / script >
< / body >
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```
