id-16
Version:
Create random id's and numbers in base 16!
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Markdown
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<img src="https://user-images.githubusercontent.com/15139826/62064395-0fcee300-b22d-11e9-98c8-6190ce3bee52.png" alt="id-16 logo">
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<p align="center">
Create random ids and numbers in base 16!
</p>
[](https://travis-ci.org/jessevdp/id-16)
[](http://standardjs.com/)
# Intro
Use the simple function to quickly generate a random base 16 ([hexadecimal](https://en.wikipedia.org/wiki/Hexadecimal)) number or create a generator and then use it to create loads of random numbers of the same length which are checked for collisions. This is useful for creating unique IDs and whatnot.
# Basic usage
Create a random hex number:
```js
var id_16 = require('id-16')
var random = id_16(10)
// e.g. 63f499b6f4
```
Create a generator and use it:
```js
var id_16 = require('id-16')
var id = id_16.generator(4)
user_1 = id() // -> 63f4
user_2 = id() // -> b6ab
```
# Documentation
All the current functions are documented. If you have any comments or suggestions please go [here](#suggestions).
## id_16([length])
This function creates a random number in base 16.
**Returns**: A number in base 16.
| param | type | description |
| --- | --- | ---|
| lenght | `Number` optional | The desired length of the return number. *(Default: 8)* |
## id_16.generator([length, expandby])
This function returns a function that creates random base 16 numbers. This generator checks the numbers for collisions. If too many collisions occur an error is thrown or (if `expandby` is defined) the length of the number is expanded.
**returns**: The generator
| param | type | description |
| --- | --- | ---|
| lenght | `Number` optional | The desired length of the return number. *(Default: 8)* |
| expandby | `Number` optional | Expand the length of the return number by this number if too many collisions occur.|
This generator also has some properties and methods:
### generator.remove(number)
Removes a number from the list of numbers that have been created by this generator, allowing the number to be created again.
| param | type | description |
| --- | --- | ---|
| number | `Number` | The number that you want to delete from the list of already 'used' numbers by **this** generator. |
### generator.list
An array containing all the numbers that have been created by **this** generator. It's used to check for collisions by the generator itself but it is open to interact with.
# creation of random numbers
The program currently uses the following function to generate the numbers:
```js
var random_number = Math.floor(Math.random() * 16)
```
This creates a number between 0 and 15 after which the number is then converted into base 16. This process is then repeated for the desired length of the number and the numbers are added onto a string. This string is what's returned by the function.
### Is it truly random?
Many people state that `Math.random()` is not truly random. I'm not going to debate whether or not this is true however I am going to show you the results I got. I ran the function in a loop creating 1000 random numbers between 0 and 15, the following graph shows just how many times each number was returned by the function:
<p align="center">
<img src="https://user-images.githubusercontent.com/15139826/62064393-0fcee300-b22d-11e9-9492-b8fc52939a08.png" alt="graph">
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</p>
As you can see the numbers are all created about as many times. I think it's good enough for this purpose but I'm open to any suggestions! So please let me know if you think you've got a better way of creating truly random numbers.
# Suggestions
If you have any suggestions or want something to be implemented, please [submit an issue](/issues) or [open a pull request](/pulls)!
# License & Disclaimer
This module is open-sourced under the MIT Licence (see [LICENSE](LICENSE) for the full license). So within some limits, you can do with the code whatever you want.
The software is provided as-is. It might work as expected — or not. Just don't blame me.