power-cartesian-product

powerful cartesian product

this module was named fast-cartesian-product before v0.0.3, now it's split into to two modules:

• fast-cartesian-product

  focusing on speed, and only work on arrays

• power-cartesian-product

  focusing on unlimited combinations, less memory, more data types

Examples

import PowerCartesianProduct from 'power-cartesian-product'

const inputs = [
  [0, 1],
  ['A', 'B'],
]

for (const combination of new PowerCartesianProduct(inputs)) {
  console.log(combination)
}

more examples

git clone https://github.com/fisker/power-cartesian-product.git
cd fast-cartesian-product
yarn
node -r esm examples/standard-52-card-deck.js
node -r esm examples/any-iterable-type.js
node -r esm examples/big-combinations.js

Files

dist/
├─ index.common.js  ( CommonJS )
├─ index.js         ( UMD )
├─ index.min.js     ( UMD, compressed )
├─ index.mjs        ( ES Module )
└─ index.min.mjs    ( ES Module, compressed )

API

combinations = new PowerCartesianProduct(sets)

Returns: combinations

sets

type: iterable | arrayLike | GeneratorFunction

*notice: GeneratorFunction is supported, not generator yet, #57

combinations

instance of PowerCartesianProduct

it's not Array, also no length

to get Array

[...combinations]

// OR

Array.from(...combinations)

// OR

const array = []

let (const combination of combinations) {
  array.push(combination)
}

// es5

var array = []
var iterator = combinations[PowerCartesianProduct.SYMBOL_ITERATOR]()
var data
while (!(data = iterator.next()).done) {
  array.push(data.value)
}

to get Set

new Set(combinations)

PowerCartesianProduct#get(index)

get nth combination

Returns: array

// 3rd combination
new PowerCartesianProduct([
  [0, 1],
  ['A', 'B'],
]).get(2)
// -> [1, 'A']

PowerCartesianProduct#getIndexes(index)

get nth combination indexes

Returns: array<number>

// 3rd combination indexes
new PowerCartesianProduct([
  [0, 1],
  ['A', 'B'],
]).getIndexes(2)
// -> [1, 0]

PowerCartesianProduct#size

a getter to get size of combinations, this might be Infinity for big combinations.

Returns: int | infinity

new PowerCartesianProduct([
  [0, 1],
  ['A', 'B'],
]).size
// -> 4

new PowerCartesianProduct(new Array(256).fill(new Array(16))).size
// -> Infinity

PowerCartesianProduct#bigSize

a getter to get BigInt size of combinations.

Returns: BigInt

new PowerCartesianProduct([
  [0, 1],
  ['A', 'B'],
]).bigSize
// -> 4n

new PowerCartesianProduct(new Array(33).fill(new Array(2 ** 32 - 1))).bigSize
// -> 772103316315349105706014416063813378269318666861765024749836830511609335567106186231578700102953323105081739246412669785553431723085370935750037827673052894357512235463946499050426982824119747058048805090828544034771248058426863536672304703225363101118206353134873876903786099067350665495893380022607743740081787109375n

PowerCartesianProduct.SYMBOL_ITERATOR

symbol to get Iterator, for environment without Symbol, it's string @@iterator, otherwise it's Symbol.iterator

if you are not sure, you should always use combinations[PowerCartesianProduct.SYMBOL_ITERATOR]()

var iterator = combinations[PowerCartesianProduct.SYMBOL_ITERATOR]()
iterator.next() // {value: [0, 1], done: false}