# flota64后面保留三位小数

1、需要转成字符串形式的：

fmt.Sprintf("%.3f", 1.23456)

strconv.ParseFloat(fmt.Sprintf("%.3f",v), 3)

2、不需要转成字符串形式的：

value = math.Trunc(value\**1e3 + 0.5)\**1e-3

加上 0.5是为了四舍五入，想保留几位小数的话把3改掉即可

封装成函数

```
func Round(f float64, n int) float64 {
    pow10_n := math.Pow10(n)
    return math.Trunc((f+0.5/pow10_n)*pow10_n) / pow10_n
}
```


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