49 lines
804 B
JavaScript
Executable File
49 lines
804 B
JavaScript
Executable File
'use strict'
|
|
|
|
var abs = Math.abs
|
|
var round = Math.round
|
|
|
|
function almostEq(a, b) {
|
|
return abs(a - b) <= 9.5367432e-7
|
|
}
|
|
|
|
//最大公约数 Greatest Common Divisor
|
|
function GCD(a, b) {
|
|
if (almostEq(b, 0)) return a
|
|
return GCD(b, a % b)
|
|
}
|
|
|
|
function findPrecision(n) {
|
|
var e = 1
|
|
|
|
while (!almostEq(round(n * e) / e, n)) {
|
|
e *= 10
|
|
}
|
|
|
|
return e
|
|
}
|
|
|
|
function num2fraction(num) {
|
|
if (num === 0 || num === '0') return '0'
|
|
|
|
if (typeof num === 'string') {
|
|
num = parseFloat(num)
|
|
}
|
|
|
|
|
|
var precision = findPrecision(num) //精确度
|
|
var number = num * precision
|
|
var gcd = abs(GCD(number, precision))
|
|
|
|
//分子
|
|
var numerator = number / gcd
|
|
//分母
|
|
var denominator = precision / gcd
|
|
|
|
//分数
|
|
return round(numerator) + '/' + round(denominator)
|
|
}
|
|
|
|
module.exports = num2fraction
|
|
|