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12 changes: 11 additions & 1 deletion README.md
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Expand Up @@ -13,7 +13,17 @@ Math.E.introspect().exponent; // "10000000000"

Interactively explore at [http://dherman.github.com/float.js](http://dherman.github.com/float.js).

## License
### How it works

[Internally](https://github.com/dherman/float.js/blob/master/float.js), this puts the number in a single-element `Float64Array` [typed array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Typed_arrays) and gets its `buffer` to read the value’s raw bits:

```javascript
(new Float64Array([n])).buffer
```

Then it converts that buffer to a string of `"1"`s and `"0"`s by viewing the buffer as a `Uint8Array` and mapping each viewed byte to a binary string with `.toString(2)`. Finally, it creates properties like `exponent` and `mantissa` by using `[]` array indexing, `.substring`, and `.slice` to extract the relevant bits.

### License

Copyright © 2012 Dave Herman

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