README
@manutero/randomjs
Humanized random functions.
Installation
npm i @manutero/randomjs
...or just copy one file to your project:
curl -s https://raw.githubusercontent.com/manutero/randomjs/main/index.js > {my-awesome-project}/src/random.js
Quick Start
const { RandomGenerator } = require("@manutero/randomjs");
const random = RandomGenerator();
random.number(1, 10); // natural number between [a,b]
// => 3
random.normal(1, 10); // natural number between [a,b] considering a normal distribution
// => 6
random.roll("2d6"); // roll some dices
// => [2, 5]
random.bet(42.4); // bet with (0..100%) chance of success.
// => false
random.unit(); // random unit (0 - 1)
// => 0.7580578515771776
random.pickOne([1, 2, 3, 4, 5]); // pick one element (all elements have same weight)
// => 1
random.pickOne([
// pick one element (considering different weights)
{ key: 1, weight: 1 },
{ key: 2, weight: 1 },
{ key: 3, weight: 9999 },
{ key: 4, weight: 1 },
]);
// => {key: 3, weight: 9999}
Dependencies
None. Just a plain .js file wrapping Math.random()
Use Case
Some uses cases I can think of...
- you just want a natural random between 1 and 10 while you aren't concern about pure mathematical correctness.
- you just want to pick an element from an array while not adding another dependency to your project (but copying 1 easy-to-read js file is ok)
- you just want to roll some dices while would be great that other guy has tested that function already.
If you're looking for a mathematically correct Random generator OR cryptographically secure random numbers, try with random-js instead
Method Detail
.number(a:int, b: int) -> int
Natural number between [a, b] (inclusive).
> random.number(1,10)
6
> random.number(1,10)
3
> random.number(1,10)
9
> random.number(1,10)
9
> random.number(1,10)
10
.normal(a: int, b: int, {skew?: int}) -> int
natural number between [a, b] (inclusive) considering a normal distribution.
> random.normal(1,10)
5
> random.normal(1,10)
4
> random.normal(1,10)
6
> random.normal(1,10)
4
> random.normal(1,10)
6
> random.normal(1,10)
6
> random.normal(1,10)
5
.roll(dice: str) -> [number]
Roll some dices
> random.roll('1d6')
[5]
> random.roll('2d12')
[4, 10]
> random.roll('3d6')
[1, 1, 5]
> random.roll('D3')
[2]
> random.roll('1D12')
[12]
.bet(options: float) -> boolean
bet with a percentage of success (expected a number between 0 - 100)
> random.bet(40.0)
false
> random.bet(40.0)
true
> random.bet(40.0)
false
> random.bet(0.0)
false
> random.bet(100.0)
true
.unit() -> float
unit random between (0, 1)
> random.unit()
0.7580578515771776
> random.unit()
0.11270887637510896
> random.unit()
0.028320789337158203
.pickOne(choices: [T], opts?: { weightKey>: string}) -> T:
pick one element from an array
> random.pickOne([1 ,2, 3, 4, 5])
3
> random.pickOne([1 ,2, 3, 4, 5])
5
> random.pickOne([1 ,2, 3, 4, 5])
5
> random.pickOne([1 ,2, 3, 4, 5])
1
Pick one element from an array with weight
> random.pickOne([
{ key: 1, weight: 10 },
{ key: 2, weight: 10 },
{ key: 3, weight: 10 },
{ key: 4, weight: 10 },
{ key: 5, weight: 10 }
])
{ key: 5, weight: 10 }
> random.pickOne([
{ key: 1, weight: 10 },
{ key: 2, weight: 10 },
{ key: 3, weight: 10 },
{ key: 4, weight: 99999 },
{ key: 5, weight: 10 }
])
{ key: 4, weight: 99999 }
.seed
Get the internal seed
> random.seed
72779816406.94533
constructor()
Force the internal seed
> r1 = RandomGenerator(42)
> r2 = RandomGenerator(42)
> r1.unit()
0.6011037519201636
> r2.unit()
0.6011037519201636
> r1.unit() === r2.unit()
true