--- /dev/null
+'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
+