safe-math-js

Safer floating-point math operations in JavaScript that return results we expect, so that 0.1 + 0.2 adds up to 0.3, e.g., instead of 0.30000000000000004. Customized and fixed from package '@dfkaye/safe-math'.

Fixings from package @dfkaye/safe-math

- 0.0003 * 100000000 = 20000 (error), (fixed result = 30000)
- 0.00000003 * 100000000 = 300000000 (error), (fixed result = 3)

Some Existing Issue of @dip1059/safe-math-js

- 0.00000003 * 1000000000000000000 = 30000000000.000004 (error), should return 30000000000. For this kind of big integer(1000000000000000000) and large decimal value(0.00000003 equivalent to 3e-8) operations, wrap the output with Math.round() or parseInt(). e.g:

``
let result = safe-math-js.multiply(0.00000003, 1000000000000000000);
console.log(Math.round(result)); //30000000000

// or

result = safe-math-js.multiply(3e-8, 1000000000000000000);
console.log(parseInt(result)); //30000000000
`
Warning: you need to check the actual output then you have to decide whether to keep the result as it is or to wrap with round() or parseInt()

Basic Usage

`
const math = require('@dip1059/safe-math-js');

console.log(math.add(0.1, 0.2));
console.log(math.minus(0.1, 0.2));
console.log(math.divide(0.1, 0.2));
console.log(math.multiply(0.1, 0.2));

`
For more usage check the tests

Documentation

See full details at https://dfkaye.com/posts/2020/08/17/safer-math-operations-in-javascript-using-tdd/.

Install

npm install @dip1059/safe-math-js

OR

yarn add @dip1059/safe-math-js`