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---
id: 587d7fa8367417b2b2512bca
title: Change the Presentation of a Bar Chart
challengeType: 6
forumTopicId: 301481
dashedName: change-the-presentation-of-a-bar-chart
---
# --description--
The last challenge created a bar chart, but there are a couple of formatting changes that could improve it:
1) Add space between each bar to visually separate them, which is done by adding a margin to the CSS for the `bar` class
2) Increase the height of the bars to better show the difference in values, which is done by multiplying the value by a number to scale the height
# --instructions--
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First, add a `margin` of `2px` to the `bar` class in the `style` tag. Next, change the callback function in the `style()` method so it returns a value `10` times the original data value (plus the `px` ).
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**Note:** Multiplying each data point by the *same* constant only alters the scale. It's like zooming in, and it doesn't change the meaning of the underlying data.
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# --hints--
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The first `div` should have a `height` of `120` pixels and a `margin` of `2` pixels.
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```js
assert(
$('div').eq(0).css('height') == '120px' & &
$('div').eq(0).css('margin-right') == '2px'
);
```
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The second `div` should have a `height` of `310` pixels and a `margin` of `2` pixels.
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```js
assert(
$('div').eq(1).css('height') == '310px' & &
$('div').eq(1).css('margin-right') == '2px'
);
```
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The third `div` should have a `height` of `220` pixels and a `margin` of `2` pixels.
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```js
assert(
$('div').eq(2).css('height') == '220px' & &
$('div').eq(2).css('margin-right') == '2px'
);
```
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The fourth `div` should have a `height` of `170` pixels and a `margin` of `2` pixels.
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```js
assert(
$('div').eq(3).css('height') == '170px' & &
$('div').eq(3).css('margin-right') == '2px'
);
```
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The fifth `div` should have a `height` of `250` pixels and a `margin` of `2` pixels.
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```js
assert(
$('div').eq(4).css('height') == '250px' & &
$('div').eq(4).css('margin-right') == '2px'
);
```
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The sixth `div` should have a `height` of `180` pixels and a `margin` of `2` pixels.
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```js
assert(
$('div').eq(5).css('height') == '180px' & &
$('div').eq(5).css('margin-right') == '2px'
);
```
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The seventh `div` should have a `height` of `290` pixels and a `margin` of `2` pixels.
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```js
assert(
$('div').eq(6).css('height') == '290px' & &
$('div').eq(6).css('margin-right') == '2px'
);
```
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The eighth `div` should have a `height` of `140` pixels and a `margin` of `2` pixels.
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```js
assert(
$('div').eq(7).css('height') == '140px' & &
$('div').eq(7).css('margin-right') == '2px'
);
```
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The ninth `div` should have a `height` of `90` pixels and a `margin` of `2` pixels.
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```js
assert(
$('div').eq(8).css('height') == '90px' & &
$('div').eq(8).css('margin-right') == '2px'
);
```
# --seed--
## --seed-contents--
```html
< style >
.bar {
width: 25px;
height: 100px;
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/* Add your code below this line */
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/* Add your code above this line */
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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")
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.style("height", (d) => (d + "px")) // Change this line
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< / script >
< / body >
```
# --solutions--
```html
< style >
.bar {
width: 25px;
height: 100px;
margin: 2px;
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 * 10 + "px"))
< / script >
< / body >
```
