2024-05-06 20:40:05 +00:00
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---
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2024-10-30 17:04:36 +00:00
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date: 20200923
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2024-05-06 20:40:05 +00:00
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id: 1accac75-7a5c-4847-977a-f0ae63454820
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title: JavaScript Math library
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---
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# ES6
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## .sign(x)
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### Returns
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- -1 if x is a negative number (including -Infinity).
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- 0 if x is zero4.
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- +1 if x is a positive number (including Infinity).
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- NaN if x is NaN or not a number.
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``` javascript
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console.log(Math.sign(-8)) // -a
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console.log(Math.sign(3)) // 1
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console.log(Math.sign(0)) // 0
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console.log(Math.sign(NaN)) // NaN
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console.log(Math.sign(-Infinity)) // -1
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console.log(Math.sign(Infinity)) // 1
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```
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## .trunc(x)
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``` javascript
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console.log(Math.trunc(3.1)) // 3
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console.log(Math.trunc(3.9)) // 3
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console.log(Math.trunc(-3.1)) // 3
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console.log(Math.trunc(-3.9)) // 3
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```
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## .cbrt(x)
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Returns the cube root of x:
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``` javascript
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console.log(Math.cbrt(8)) // 2
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console.log(Math.cbrt(27)) // 3
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```
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