extended-hamming-code

extended hamming code allows you to encode and decode binary strings, it has not any dependencies.Works only with binary strings. For example '101010'.

extended means first index of code handle odd-even of all code.

It is UMD module. It means it capable of working in AMD, CommonJS-like, nodejs, browrser environments. For more information go to UMD.

usage

npm install extended-hamming-code -S

import ExtendHammingCode from 'extended-hamming-code';

const {
  encode,
  decode,
} = ExtendHammingCode.setConfig({
  pow: 4
})

Options

| Name | Type | Default | Description | |------|--------|---------|------------------------------------------------------------------------------------------------------------------------------| | pow | Number | 4 | preset max size of encode size, you will get [Math.pow(2, pow), Math.pow(2, pow) - pow - 1] hamming code's encode and decode |

relation of 'pow' and size :

| pow | size | Description | |-----|----------------------------------------------|------------------------------------------------------------------------------------| | 4 | [16, 11] | Maximum encoding 11 bit, Maximum return 16 bit | | 5 | [32, 26] | Maximum encoding 26 bit, Maximum return 32 bit | | 6 | [64, 57] | Maximum encoding 57 bit, Maximum return 64 bit | | n | [Math.pow(2, n), Math.pow(2, n) - n - 1] | Maximum encoding Math.pow(2, n) - n - 1 bit, Maximum return Math.pow(2, n) bit |

example

when we set 4 to pow，we will get [16, 11] hamming code's encode and decode methord.

in this case, maximum encode 11 bit. when encode too long like this case below. str will be splited as many parts，and be encoded for each of them. join each other and return.

import ExtendHammingCode from 'extended-hamming-code';

const {
  encode,
  decode,
} = ExtendHammingCode.setConfig({
  pow: 4
})

const str = '1010101010101010101010101010101010';
const encodeRes = encode(str);
const decodeRes = decode(encodeRes);
const {
  code,
  correct,
  originCode,
  decodeResult,
} = decodeRes;
console.log(`encode:${str}, `, encodeRes);
console.log(`decode:${encodeRes}, `, decodeRes);
console.log('is correct?', correct, code === str)

result of decode:

| key | type | Description | |----------------|---------|--------------------------| | code | String | result code of decode | | correct | Boolean | correct or not | | originCode | String | input data | | decodeResult | Array | all parts of decode data |