stats.go

package main

import (
	"fmt"
	"math"

	"github.com/aclements/go-moremath/stats"
)

type StatCounter struct {
	stats.Sample
}

func (sc *StatCounter) Add(s float64) {
	sc.Sample.Xs = append(sc.Sample.Xs, s)
}

func (sc *StatCounter) PrintStats(msg string) {
	if len(sc.Xs) == 0 {
		return
	}
	sc.Sort()

	fmt.Printf("Avg %s speed: %s/s\n", msg, prettyByteSize(int64(MEBIBYTE/sc.Mean())))
	fmt.Printf("P1  %s speed: %s/s\n", msg, prettyByteSize(int64(MEBIBYTE/sc.Quantile(0.99))))
	fmt.Printf("P10 %s speed: %s/s\n", msg, prettyByteSize(int64(MEBIBYTE/sc.Quantile(0.9))))
}

func prettyByteSize(b int64) string {
	bf := float64(b)
	for _, unit := range []string{"", "Ki", "Mi", "Gi", "Ti"} {
		if math.Abs(bf) < 1024.0 {
			return fmt.Sprintf("%3.1f %sB", bf, unit)
		}
		bf /= 1024.0
	}
	return fmt.Sprintf("%.1f PiB", bf)
}