84 lines
2.8 KiB
Markdown
84 lines
2.8 KiB
Markdown
|
---
|
||
|
|
id: 587d7fa8367417b2b2512bcd
|
||
|
|
title: Create a Bar for Each Data Point in the Set
|
||
|
|
required:
|
||
|
|
- src: 'https://cdnjs.cloudflare.com/ajax/libs/d3/4.3.0/d3.min.js'
|
||
|
|
challengeType: 6
|
||
|
|
---
|
||
|
|
|
||
|
|
## Description
|
||
|
|
<section id='description'>
|
||
|
|
The last challenge added only one rectangle to the <code>svg</code> element to represent a bar. Here, you'll combine what you've learned so far about <code>data()</code>, <code>enter()</code>, and SVG shapes to create and append a rectangle for each data point in <code>dataset</code>.
|
||
|
|
A previous challenge showed the format for how to create and append a <code>div</code> for each item in <code>dataset</code>:
|
||
|
|
<blockquote>d3.select("body").selectAll("div")<br> .data(dataset)<br> .enter()<br> .append("div")</blockquote>
|
||
|
|
There are a few differences working with <code>rect</code> elements instead of <code>divs</code>. The <code>rects</code> must be appended to an <code>svg</code> element, not directly to the <code>body</code>. Also, you need to tell D3 where to place each <code>rect</code> within the <code>svg</code> area. The bar placement will be covered in the next challenge.
|
||
|
|
</section>
|
||
|
|
|
||
|
|
## Instructions
|
||
|
|
<section id='instructions'>
|
||
|
|
Use the <code>data()</code>, <code>enter()</code>, and <code>append()</code> methods to create and append a <code>rect</code> for each item in <code>dataset</code>. The bars should display all on top of each other, this will be fixed in the next challenge.
|
||
|
|
</section>
|
||
|
|
|
||
|
|
## Tests
|
||
|
|
<section id='tests'>
|
||
|
|
|
||
|
|
```yml
|
||
|
|
- text: Your document should have 9 <code>rect</code> elements.
|
||
|
|
testString: 'assert($("rect").length == 9, "Your document should have 9 <code>rect</code> elements.");'
|
||
|
|
- text: Your code should use the <code>data()</code> method.
|
||
|
|
testString: 'assert(code.match(/\.data/g), "Your code should use the <code>data()</code> method.");'
|
||
|
|
- text: Your code should use the <code>enter()</code> method.
|
||
|
|
testString: 'assert(code.match(/\.enter/g), "Your code should use the <code>enter()</code> method.");'
|
||
|
|
- text: Your code should use the <code>append()</code> method.
|
||
|
|
testString: 'assert(code.match(/\.append/g), "Your code should use the <code>append()</code> method.");'
|
||
|
|
|
||
|
|
```
|
||
|
|
|
||
|
|
</section>
|
||
|
|
|
||
|
|
## Challenge Seed
|
||
|
|
<section id='challengeSeed'>
|
||
|
|
|
||
|
|
<div id='html-seed'>
|
||
|
|
|
||
|
|
```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")
|
||
|
|
// Add your code below this line
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
// Add your code above this line
|
||
|
|
.attr("x", 0)
|
||
|
|
.attr("y", 0)
|
||
|
|
.attr("width", 25)
|
||
|
|
.attr("height", 100);
|
||
|
|
</script>
|
||
|
|
</body>
|
||
|
|
```
|
||
|
|
|
||
|
|
</div>
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
</section>
|
||
|
|
|
||
|
|
## Solution
|
||
|
|
<section id='solution'>
|
||
|
|
|
||
|
|
```js
|
||
|
|
// solution required
|
||
|
|
```
|
||
|
|
</section>
|