17be165d66
* added solutions to data visualization with D3 * Update add-a-tooltip-to-a-d3-element.english.md * Update add-attributes-to-the-circle-elements.english.md * Update add-axes-to-a-visualization.english.md * Update add-document-elements-with-d3.english.md * Update add-inline-styling-to-elements.english.md * Update add-labels-to-scatter-plot-circles.english.md * Update change-styles-based-on-data.english.md * Update change-the-color-of-an-svg-element.english.md * Update change-the-presentation-of-a-bar-chart.english.md * Update create-a-bar-for-each-data-point-in-the-set.english.md * Update create-a-linear-scale-with-d3.english.md * Update create-a-scatterplot-with-svg-circles.english.md * Update display-shapes-with-svg.english.md * Update dynamically-change-the-height-of-each-bar.english.md * Update dynamically-set-the-coordinates-for-each-bar.english.md * Update invert-svg-elements.english.md * Update learn-about-svg-in-d3.english.md * Update select-a-group-of-elements-with-d3.english.md * Update set-a-domain-and-a-range-on-a-scale.english.md * Update style-d3-labels.english.md * Update work-with-dynamic-data-in-d3.english.md * Update use-a-pre-defined-scale-to-place-elements.english.md * Update use-dynamic-scales.english.md * Update use-the-d3.max-and-d3.min-functions-to-find-minimum-and-maximum-values-in-a-dataset.english.md * Update work-with-data-in-d3.english.md
114 lines
2.9 KiB
Markdown
114 lines
2.9 KiB
Markdown
---
|
|
id: 587d7fa8367417b2b2512bcd
|
|
title: Create a Bar for Each Data Point in the Set
|
|
challengeType: 6
|
|
forumTopicId: 301482
|
|
---
|
|
|
|
## 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>:
|
|
|
|
```js
|
|
d3.select("body").selectAll("div")
|
|
.data(dataset)
|
|
.enter()
|
|
.append("div")
|
|
```
|
|
|
|
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
|
|
tests:
|
|
- text: Your document should have 9 <code>rect</code> elements.
|
|
testString: assert($('rect').length == 9);
|
|
- text: Your code should use the <code>data()</code> method.
|
|
testString: assert(code.match(/\.data/g));
|
|
- text: Your code should use the <code>enter()</code> method.
|
|
testString: assert(code.match(/\.enter/g));
|
|
- text: Your code should use the <code>append()</code> method.
|
|
testString: assert(code.match(/\.append/g));
|
|
|
|
```
|
|
|
|
</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'>
|
|
|
|
```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", 0)
|
|
.attr("y", 0)
|
|
.attr("width", 25)
|
|
.attr("height", 100);
|
|
</script>
|
|
</body>
|
|
|
|
```
|
|
|
|
</section>
|