fzred / calculatorjs

Accurately arithmetic library. 解决Javascript浮点运算精度问题。

Calculatorjs

中文文档

> 2.1 + 2.2
4.300000000000001
> calc(' 2.1 + 2.2 ')
4.3

Usage

Using NPM:

npm install --save calculatorjs

In Node.js or Browser:

const calc = require('calculatorjs')

console.log(calc(' 0.1*(0.1+0.1) '))

Direct <script> Include

<script src="calc.js"></script>
<script>
    console.log(calc(' 0.1 * (0.1 + 0.1) '))
</script>

DOC

Arithmetic expression

calc(' 1 + (2 * 3 - 1) / 4 * -1 ')

Support + - * / ( ) minus

API

calc.add(0.1, 0.2) // 0.3
calc.sub(0.1, 0.2) // -0.1
calc.mul(0.1, 0.2) // 0.02
calc.div(0.1, 0.2) // 0.5
calc.round(0.555, 2) // 0.56

License

Distributed under MIT License.

calculatorjs's Issues

calc(+1) 等于 0

calc(+1) // 0，应该等于 1

number add error

var res = calc.add("1700","1700"); //17001700

var res = calc.add("1700.00","1700.00");//3400

calc.add(0.1 + 0.2, 0)

> 0.1+0.2
0.30000000000000004
> require('calculatorjs').add(0.1, 0.2)
0.3
> require('calculatorjs').add(0.1 + 0.2, 0)
0.30000000000000004

round 精度有问题

/**

• 四舍五入
• @param {*} number
• @param {*} fraction
  */
  function round(number, fraction) {
  return Math.round(number * Math.pow(10, fraction)) / Math.pow(10, fraction)
  }

round 精度有问题
round(0.285,2) = 0.28
round(0.135,2) = 0.14
目前暂时改成

function round(number, fraction) = (
return Math.round((number + Number.EPSILON) * Math.pow(10, fraction)) / Math.pow(10, fraction)
).toFixed(fraction);
}

round(0.285,2) = 0.29
round(0.135,2) = 0.14

大数的相乘不准，有办法解决吗？

calc("14785570.2399 *1231231.12311")