lexicographic-integer

create lexicographic string keys for positive integers without zero-padding

Note: there is some loss of precision for very large values (> 2^32)

example

var convert = require('lexicographic-integer');
console.log(convert(12345));

output:

[ 252, 47, 62 ]

hex list

var convert = require('lexicographic-integer');

for (var n = 0; n < 5; n++) {
    console.log(n, convert(n, 'hex'));
}

console.log('...');

for (var n = 248; n < 257; n++) {
    console.log(n, convert(n, 'hex'));
}

console.log('...');

for (var n = 5000; n < 5005; n++) {
    console.log(n, convert(n, 'hex'));
}

console.log('...');

for (var n = 21378213; n < Number.MAX_VALUE; n *= 1513254198219212) {
    console.log(n, convert(n, 'hex'));
}

output:

0 '00'
1 '01'
2 '02'
3 '03'
4 '04'
...
248 'f8'
249 'f9'
250 'fa'
251 'fb00'
252 'fb01'
253 'fb02'
254 'fb03'
255 'fb04'
256 'fb05'
...
5000 'fc128d'
5001 'fc128e'
5002 'fc128f'
5003 'fc1290'
5004 'fc1291'
...
21378213 'fe014633aa'
3.2350670572674536e+22 'ff2afedb3776c0'
4.895478805930646e+37 'ff5dfe935164a0'
7.408103855367726e+52 'ff8ffec6004cb6'
1.121034425997914e+68 'ffc2fe850f8af8'
1.696410051489608e+83 'fff4feb2d6c188'
2.5670996323179187e+98 'fffb2bfef05dd80e'
3.884674295852086e+113 'fffb5efea187f6ca'
5.87849968691243e+128 'fffb90fed91aaefe'
8.895664330450558e+143 'fffbc3fe91e5fa5b'
1.3461401394003201e+159 'fffbf5fec417daf6'
2.03705221733893e+174 'fffc0128fe83c74c6d'
3.08257781987989e+189 'fffc015afeb11d9526'
4.6647238272706696e+204 'fffc018cfeee0ce3b1'
7.058912915150531e+219 'fffc01bffe9ff97c9f'
1.0681929603715358e+235 'fffc01f1fed7031d45'
1.6164474817904348e+250 'fffc0224fe907e1097'
2.4460959380202488e+265 'fffc0256fec2341e25'
3.701564947456103e+280 'fffc0289fe828237a0'
5.601408696719025e+295 'fffc02bbfeaf68a916'

methods

var convert = require('lexicographic-integer')

convert(n, encoding='array')

If encoding is undefined or 'array', return an array of byte values between 0 and 255, inclusive for the integer n.

If encoding is 'hex', return a lexicographic hex string for the integer n.

install

With npm do:

npm install lexicographic-number

license

MIT