README

BigFixed

A pure javascript big fixed point number library base on BigInt.

Install

npm install bigfixed

Description

BigFixed range: ( -Inf, -(2**(-64)) ] & 0 & [ 2**(-64), +Inf )

BigFixed struct: signed BigInt <N bits integer part . 64 bits fraction part>

NOTE: this lib is calculate by binary but not decimal number,

BigFixed(0.1).add(0.2).toString() === "0.30000000000000004"

Compare

Compare of big number lib
test number: 3838.261003615915, 
test count: 100000

Execution time in nano seconds(1e-9s):
Operate   BigFixed  BigNumber Big       Decimal   
new       580       750       410       690       
add       90        210       240       270       
sub       120       300       490       500       
mul       210       420       1220      710       
div       800       3760      6720      3360      
pow       380       1360      3950      2330      
str       530       220       410       250

Usage

BigFixed own prototype names

[
  'constructor', 'clone',     'isZero',
  'isNegative',  'isInteger', 'eq',
  'lt',          'lte',       'gt',
  'gte',         'neg',       'abs',
  'add',         'sub',       'mul',
  'div',         'mod',       'pow',
  'not',         'and',       'or',
  'xor',         'lShift',    'rShift',
  'toInteger',   'toNumber',  'toJSON',
  'toString'
]

Create

const BigFixed = require('bigfixed');

console.log(BigFixed(-3.14));
// BigFixed { fixed: -57922776391447994368n }

console.log(new BigFixed(-3.14));
// BigFixed { fixed: -57922776391447994368n }

console.log(BigFixed(-3.14).toString());
// -3.14000000000000012

console.log(BigFixed(-3.14).toNumber());
// -3.14

console.log(BigFixed(-3.14).toString(2));
// -11.001000111101011100001010001111010111000010100011111

console.log(BigFixed(-3.14).toString(8));
// -3.10753412172702437

console.log(BigFixed(-3.14).toString(16));
// -3.23d70a3d70a3e

console.log(BigFixed(' -3.14 ').toString());
// -3.14

console.log(BigFixed('0b0111').toString());
// 7

console.log(BigFixed('0xff').toString());
// 255

console.log(BigFixed(true).toString());
// 1

console.log(BigFixed(false).toString());
// 0

Arithmetic

console.log(BigFixed(125.25).add(100).toString());
// 225.25
console.log(BigFixed(Number.MAX_SAFE_INTEGER).add(Number.MAX_SAFE_INTEGER).toString());
// 18014398509481982

console.log(BigFixed(125.25).sub(0.125).toString());
// 125.125
console.log(BigFixed(Number.MAX_SAFE_INTEGER).sub(Number.MAX_SAFE_INTEGER).toString());
// 0

console.log(BigFixed(125.25).mul(100).toString());
// 12525
console.log(BigFixed(Number.MAX_SAFE_INTEGER).mul(Number.MAX_SAFE_INTEGER).toString());
// 81129638414606663681390495662081

console.log(BigFixed(125.25).div(8).toString());
// 15.65625
console.log(BigFixed(2).div(3).toString());
// 0.6666666666666666

console.log(BigFixed(8).mod(3).toString());
// 2
console.log(BigFixed(0.8).mod(0.3).toString());
// 0.20000000000000007

console.log(BigFixed(5).pow(2).toString());
// 25
console.log(BigFixed(3.14).pow(100).toString());
// 49313384166056347098523752010452971971940876154701.029803568081556285

Logical

console.log('Logical');

console.log(BigFixed(0x0f).not().toString(16));
// -f.0000000000000001

console.log(BigFixed(0x0f).not().not().toString(16));
// f

console.log(BigFixed(0x0f).and(0xf0).toString(16));
// 0

console.log(BigFixed(0x0f).or(0xf0).toString(16));
// ff

console.log(BigFixed(0x0f).xor(0xf0).toString(16));
// ff

console.log(BigFixed(0x0f).lShift(1).toString(16));
// 1e

console.log(BigFixed(0x0f).rShift(1).toString(16));
// 7.8

To integer

same as Math.round, Math.ceil, Math.floor, default BigFixed.ROUND

console.log(BigFixed(3.51).toInteger(BigFixed.CEIL).toString());
// 4
console.log(BigFixed(3.51).toInteger().toString());
// 4
console.log(BigFixed(3.51).toInteger(BigFixed.FLOOR).toString());
// 3

console.log(BigFixed(3.49).toInteger(BigFixed.CEIL).toString());
// 4
console.log(BigFixed(3.49).toInteger().toString());
// 3
console.log(BigFixed(3.49).toInteger(BigFixed.FLOOR).toString());
// 3

Test

jest

Usage no npm install needed!