protoc-gen-kit/pkg/xmath/math.go

package xmath

import (
	"fmt"
	"math"
	"math/rand"
	"strconv"
	"strings"
)

// 小数点后 n 位 - 四舍五入
func RoundedFixed(val float64, n int) float64 {
	shift := math.Pow(10, float64(n))
	fv := 0.0000000001 + val //对浮点数产生.xxx999999999 计算不准进行处理
	return math.Floor(fv*shift+.5) / shift
}

// 小数点后 n 位 - 舍去
func TruncRound(val float64, n int) float64 {
	floatStr := fmt.Sprintf("%."+strconv.Itoa(n+1)+"f", val)
	temp := strings.Split(floatStr, ".")
	var newFloat string
	if len(temp) < 2 || n >= len(temp[1]) {
		newFloat = floatStr
	} else {
		newFloat = temp[0] + "." + temp[1][:n]
	}
	inst, _ := strconv.ParseFloat(newFloat, 64)
	return inst
}

// RandInt64 随机范围取值
func RandInt64(min, max int64) int64 {
	if min >= max || min == 0 || max == 0 {
		return max
	}
	return rand.Int63n(max-min) + min
}
func FloatWithoutRightDot(n float64) string {
	s := fmt.Sprintf("%.2f", n)
	ss := strings.Split(s, ".")
	ss1 := strings.TrimRight(ss[1], "0")
	if ss1 == "" {
		return ss[0]
	} else {
		return fmt.Sprintf("%s.%s", ss[0], ss1)
	}
}

func NumberFormat(str string) string {
	length := len(str)
	if length < 4 {
		return str
	}
	arr := strings.Split(str, ".") //用小数点符号分割字符串,为数组接收
	length1 := len(arr[0])
	if length1 < 4 {
		return str
	}
	count := (length1 - 1) / 3
	for i := 0; i < count; i++ {
		arr[0] = arr[0][:length1-(i+1)*3] + "," + arr[0][length1-(i+1)*3:]
	}
	return strings.Join(arr, ".") //将一系列字符串连接为一个字符串，之间用sep来分隔。
}

func ConvertInt64(s string) int64 {
	v, _ := strconv.ParseInt(s, 10, 64)
	return v
}

//
//func Round(f float64, n int32) float64 {
//	v, _ := decimal.NewFromFloat(f).Round(n).Float64()
//	return v
//}