111 lines
2.5 KiB
Markdown
111 lines
2.5 KiB
Markdown
---
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id: 587d7fa8367417b2b2512bcd
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title: Create a Bar for Each Data Point in the Set
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challengeType: 6
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forumTopicId: 301482
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dashedName: create-a-bar-for-each-data-point-in-the-set
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---
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# --description--
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The last challenge added only one rectangle to the `svg` element to represent a bar. Here, you'll combine what you've learned so far about `data()`, `enter()`, and SVG shapes to create and append a rectangle for each data point in `dataset`.
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A previous challenge showed the format for how to create and append a `div` for each item in `dataset`:
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```js
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d3.select("body").selectAll("div")
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.data(dataset)
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.enter()
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.append("div")
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```
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There are a few differences working with `rect` elements instead of `divs`. The `rects` must be appended to an `svg` element, not directly to the `body`. Also, you need to tell D3 where to place each `rect` within the `svg` area. The bar placement will be covered in the next challenge.
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# --instructions--
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Use the `data()`, `enter()`, and `append()` methods to create and append a `rect` for each item in `dataset`. The bars should display all on top of each other; this will be fixed in the next challenge.
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# --hints--
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Your document should have 9 `rect` elements.
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```js
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assert($('rect').length == 9);
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```
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Your code should use the `data()` method.
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```js
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assert(code.match(/\.data/g));
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```
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Your code should use the `enter()` method.
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```js
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assert(code.match(/\.enter/g));
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```
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Your code should use the `append()` method.
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```js
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assert(code.match(/\.append/g));
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```
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# --seed--
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## --seed-contents--
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```html
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<body>
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<script>
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const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];
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const w = 500;
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const h = 100;
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const svg = d3.select("body")
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.append("svg")
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.attr("width", w)
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.attr("height", h);
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svg.selectAll("rect")
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// Add your code below this line
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// Add your code above this line
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.attr("x", 0)
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.attr("y", 0)
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.attr("width", 25)
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.attr("height", 100);
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</script>
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</body>
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```
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# --solutions--
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```html
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<body>
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<script>
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const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];
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const w = 500;
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const h = 100;
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const svg = d3.select("body")
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.append("svg")
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.attr("width", w)
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.attr("height", h);
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svg.selectAll("rect")
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.data(dataset)
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.enter()
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.append("rect")
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.attr("x", 0)
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.attr("y", 0)
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.attr("width", 25)
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.attr("height", 100);
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</script>
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</body>
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```
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