71 lines
1.4 KiB
Markdown
71 lines
1.4 KiB
Markdown
---
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id: cf1391c1c11feddfaeb4bdef
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title: Create Decimal Numbers with JavaScript
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/ca8GEuW'
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forumTopicId: 16826
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localeTitle: 创建一个小数
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---
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## Description
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<section id='description'>
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我们也可以把小数存储到变量中。小数也被称作<dfn>浮点数</dfn> 。
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<strong>提示</strong><br>不是所有的实数都可以用 <dfn>浮点数</dfn> 来表示。因为可能存在四舍五入的错误，<a href="https://en.wikipedia.org/wiki/Floating_point#Accuracy_problems" target="_blank">详情查看</a>。
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</section>
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## Instructions
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<section id='instructions'>
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创建一个变量<code>myDecimal</code>并给它赋值一个浮点数。(例如<code>5.21</code>)。
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>myDecimal</code>应该是一个数字。
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testString: assert(typeof myDecimal === "number");
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- text: <code>myDecimal</code>应该包含小数点。
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testString: assert(myDecimal % 1 != 0);
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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var ourDecimal = 5.7;
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// Only change code below this line
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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(function(){if(typeof myDecimal !== "undefined"){return myDecimal;}})();
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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var myDecimal = 9.9;
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```
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</section>
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