2020-02-25 22:53:07 -06:00
---
id: 5d8a4cfbe6b6180ed9a1ca09
title: Part 44
challengeType: 0
2020-06-24 16:22:14 +09:00
isHidden: true
2020-02-25 22:53:07 -06:00
---
## Description
< section id = 'description' >
The line needs x and y values for each point of data. Chain `x` to the line and pass it a "d function". Here's how that will look:
```js
.x(d => d.year)
```
You will be passing your `data` array to this line function, where it will go through each item in the array(`d` ) and create an x value based on the year(`d.year` ).
This is the first place you have seen a "d function". These are common in D3 and that is how I will refer to them throughout this project.
< / section >
## Instructions
< section id = 'instructions' >
< / section >
## Tests
< section id = 'tests' >
```yml
tests:
- text: test-text
testString: assert(/const twitterLine = d3\.line\(\)\s*\.x\s*\(\s*d\s*=>\s*d\.year\s*\)/g.test(code));
```
< / section >
## Challenge Seed
< section id = 'challengeSeed' >
< div id = 'html-seed' >
```html
< script >
const data = [
{ year: 2012, followers: { twitter: 2594, tumblr: 401, instagram: 83 }},
{ year: 2013, followers: { twitter: 3049, tumblr: 440, instagram: 192 }},
{ year: 2014, followers: { twitter: 3511, tumblr: 415, instagram: 511 }},
{ year: 2015, followers: { twitter: 3619, tumblr: 492, instagram: 1014 }},
{ year: 2016, followers: { twitter: 4046, tumblr: 543, instagram: 2066 }},
{ year: 2017, followers: { twitter: 3991, tumblr: 701, instagram: 3032 }},
{ year: 2018, followers: { twitter: 3512, tumblr: 1522, instagram: 4512 }},
{ year: 2019, followers: { twitter: 3274, tumblr: 1989, instagram: 4715 }},
{ year: 2020, followers: { twitter: 2845, tumblr: 2040, instagram: 4801 }}
];
< / script >
< script >
const svgMargin = 70,
svgWidth = 700,
svgHeight = 500,
twitterColor = '#7cd9d1 ',
tumblrColor = '#f6dd71 ',
instagramColor = '#fd9b98 ';
const lineGraph = d3.select('.dashboard')
.append('svg')
.attr('width', svgWidth)
.attr('height', svgHeight);
const yScale = d3.scaleLinear()
.domain([0, 5000])
.range([svgHeight - svgMargin, svgMargin]);
const xScale = d3.scaleLinear()
.domain([2012, 2020])
.range([svgMargin, svgWidth - svgMargin]);
const yAxis = d3.axisLeft(yScale)
.ticks(6, '~s');
const xAxis = d3.axisBottom(xScale)
.tickFormat(d3.format(''))
.tickPadding(10);
lineGraph.append('g')
.call(yAxis)
.attr('transform', `translate(${svgMargin}, 0)` )
.style('font', '10px verdana');
lineGraph.append('g')
.call(xAxis)
.attr('transform', `translate(0, ${svgHeight - svgMargin})` )
.selectAll('text')
.style('transform', 'translate(-12px, 0) rotate(-50deg)')
.style('text-anchor', 'end')
.style('cursor', 'pointer')
.style('font', '10px verdana');
const twitterLine = d3.line()
< / script >
```
< / div >
### Before Test
< div id = 'html-setup' >
```html
<!DOCTYPE html>
< html >
< head >
< title > D3 Dashboard< / title >
< style >
body {
background-color: #ccc ;
padding: 100px 10px;
}
.dashboard {
width: 980px;
height: 500px;
background-color: white;
box-shadow: 5px 5px 5px 5px #888 ;
margin: auto;
display: flex;
align-items: center;
}
< / style >
< / head >
< body >
< div class = "dashboard" > < / div >
< / body >
< / html >
```
< / div >
< / section >
## Solution
< section id = 'solution' >
```html
< script >
const data = [
{ year: 2012, followers: { twitter: 2594, tumblr: 401, instagram: 83 }},
{ year: 2013, followers: { twitter: 3049, tumblr: 440, instagram: 192 }},
{ year: 2014, followers: { twitter: 3511, tumblr: 415, instagram: 511 }},
{ year: 2015, followers: { twitter: 3619, tumblr: 492, instagram: 1014 }},
{ year: 2016, followers: { twitter: 4046, tumblr: 543, instagram: 2066 }},
{ year: 2017, followers: { twitter: 3991, tumblr: 701, instagram: 3032 }},
{ year: 2018, followers: { twitter: 3512, tumblr: 1522, instagram: 4512 }},
{ year: 2019, followers: { twitter: 3274, tumblr: 1989, instagram: 4715 }},
{ year: 2020, followers: { twitter: 2845, tumblr: 2040, instagram: 4801 }}
];
< / script >
< script >
const svgMargin = 70,
svgWidth = 700,
svgHeight = 500,
twitterColor = '#7cd9d1 ',
tumblrColor = '#f6dd71 ',
instagramColor = '#fd9b98 ';
const lineGraph = d3.select('.dashboard')
.append('svg')
.attr('width', svgWidth)
.attr('height', svgHeight);
const yScale = d3.scaleLinear()
.domain([0, 5000])
.range([svgHeight - svgMargin, svgMargin]);
const xScale = d3.scaleLinear()
.domain([2012, 2020])
.range([svgMargin, svgWidth - svgMargin]);
const yAxis = d3.axisLeft(yScale)
.ticks(6, '~s');
const xAxis = d3.axisBottom(xScale)
.tickFormat(d3.format(''))
.tickPadding(10);
lineGraph.append('g')
.call(yAxis)
.attr('transform', `translate(${svgMargin}, 0)` )
.style('font', '10px verdana');
lineGraph.append('g')
.call(xAxis)
.attr('transform', `translate(0, ${svgHeight - svgMargin})` )
.selectAll('text')
.style('transform', 'translate(-12px, 0) rotate(-50deg)')
.style('text-anchor', 'end')
.style('cursor', 'pointer')
.style('font', '10px verdana');
const twitterLine = d3.line()
.x(d => d.year)
< / script >
```
< / section >
