README
BigDecimal.js
BigInt based BigDecimal implementation for Node.js 10.4 and above. This implementation is inspired from java BigDecimal class. This implementation is faster than popular big decimal libraries for most operations. See benchmarks results part below for comparison of each operation.
Advantages of this library
- Faster than other BigDecimal libraries because of native BigInt
- Simple API that is almost same with Java's BigDecimal
- No dependencies
- Well tested
- Includes type definition file
Installation
npm install bigdecimal.js
Usage
- The example usage is given below:
// Single unified constructor for multiple values
const { Big } = require('bigdecimal.js');
// Construct from a string and clone it
const x = Big('1.1111111111111111111111');
const y = new Big(x); // you can also use 'new'
const z = x.add(y);
console.log(z.toString()); // 2.2222222222222222222222
// You can also construct from a number or BigInt:
const u = Big(1.1);
const v = Big(2n);
console.log(u.toString()); // 1.1
console.log(v.toString()); // 2
You can use MathContext to set precision and rounding mode for a specific operation:
const { Big, MC, RoundingMode } = require('bigdecimal.js');
const x = Big('1');
const y = Big('3');
// MC is MathContext constructor that can be used with or without `new`
const res1 = x.divideWithMathContext(y, MC(3));
console.log(res1.toString()); // 0.333
const res2 = x.divideWithMathContext(y, new MC(3, RoundingMode.UP));
console.log(res2.toString()); // 0.334
try {
x.divide(y);
// throws since full precision is requested but it is not possible
} catch (e) {
console.log(e); // RangeError: Non-terminating decimal expansion; no exact representable decimal result.
}
Documentation
Testing
- Install dependencies:
npm i
- Compile:
npm run compile
- Run tests:
npm test
Running Benchmarks
There is a benchmark suite that compares
- This library
- big.js
- GWT based BigDecimal
To run the benchmark run npm install
and then npm run benchmark
.
Benchmark Results
For now, benchmarked against big.js and bigdecimal.
Test Machine:
- M1 2020 Macbook Air
- 8 GB Ram
- MacOS Monterey 12.0.1
Update Date: January 7th 2022
Library versions used:
- big.js 6.1.1
- (this library) bigdecimal.js 1.1.1
- bigdecimal 0.6.1
Each operation is run with fixed set of decimal numbers composed of both simple and complex numbers.
Micro benchmark framework used is benchmark. Check out benchmarks folder for source code of benchmarks.
For now, benchmarked the following operations, all operations will be added soon.
Operations per second(op/s):
Operation | Bigdecimal.js | Big.js | GWT | Winner |
---|---|---|---|---|
Add | 79,130 | 18,675 | 85.21 | BigDecimal.js |
Multiply | 495,894 | 33,534 | 2,607 | BigDecimal.js |
Subtract | 72,754 | 18,190 | 88.47 | BigDecimal.js |
Divide | 15,123 | 1,122 | 658 | BigDecimal.js |
Abs | 751,232 | 1,405,722 | 13,732 | Big.js |
Compare | 529,009 | 1,152,995 | 1,010,368 | Big.js |
Remainder | 9,705 | 3,878 | 2,487 | BigDecimal.js |