SI prefix conversion

si-prefix-conversion.go

package main

import (
  "fmt"
  "math"
)

type Ranges struct {
	Divider float64
	Suffix  string
}

func formatUnitNumber(n float64, fixNum int64) (result string) {
	r := []Ranges{
		{Divider: 1000000000, Suffix: "G"},
		{Divider: 1000000, Suffix: "M"},
		{Divider: 1000, Suffix: "k"},
		{Divider: 1, Suffix: ""},
		{Divider: 0.001, Suffix: "m"},
		{Divider: 0.000001, Suffix: "u"},
		{Divider: 0.000000001, Suffix: "n"},
		{Divider: 0.000000000001, Suffix: "p"},
	}

	for i := 0; i < len(r); i++ {
		if n >= r[i].Divider {
			result = fmt.Sprint(math.Floor((n/r[i].Divider)*100)/100) + r[i].Suffix
			return
		}
	}

	result = fmt.Sprint(n)
	return
}

func main() {
  // 0.0000001 -> 100.00n
  fmt.Println(formatUnitNumber(0.0000001, 2))
  
}