You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
67 lines
1.6 KiB
67 lines
1.6 KiB
//
|
|
// Written by Maxim Khitrov (November 2012)
|
|
//
|
|
|
|
package flowrate
|
|
|
|
import (
|
|
"math"
|
|
"strconv"
|
|
"time"
|
|
)
|
|
|
|
// clockRate is the resolution and precision of clock().
|
|
const clockRate = 20 * time.Millisecond
|
|
|
|
// czero is the process start time rounded down to the nearest clockRate
|
|
// increment.
|
|
var czero = time.Now().Round(clockRate)
|
|
|
|
// clock returns a low resolution timestamp relative to the process start time.
|
|
func clock() time.Duration {
|
|
return time.Now().Round(clockRate).Sub(czero)
|
|
}
|
|
|
|
// clockToTime converts a clock() timestamp to an absolute time.Time value.
|
|
func clockToTime(c time.Duration) time.Time {
|
|
return czero.Add(c)
|
|
}
|
|
|
|
// clockRound returns d rounded to the nearest clockRate increment.
|
|
func clockRound(d time.Duration) time.Duration {
|
|
return (d + clockRate>>1) / clockRate * clockRate
|
|
}
|
|
|
|
// round returns x rounded to the nearest int64 (non-negative values only).
|
|
func round(x float64) int64 {
|
|
if _, frac := math.Modf(x); frac >= 0.5 {
|
|
return int64(math.Ceil(x))
|
|
}
|
|
return int64(math.Floor(x))
|
|
}
|
|
|
|
// Percent represents a percentage in increments of 1/1000th of a percent.
|
|
type Percent uint32
|
|
|
|
// percentOf calculates what percent of the total is x.
|
|
func percentOf(x, total float64) Percent {
|
|
if x < 0 || total <= 0 {
|
|
return 0
|
|
} else if p := round(x / total * 1e5); p <= math.MaxUint32 {
|
|
return Percent(p)
|
|
}
|
|
return Percent(math.MaxUint32)
|
|
}
|
|
|
|
func (p Percent) Float() float64 {
|
|
return float64(p) * 1e-3
|
|
}
|
|
|
|
func (p Percent) String() string {
|
|
var buf [12]byte
|
|
b := strconv.AppendUint(buf[:0], uint64(p)/1000, 10)
|
|
n := len(b)
|
|
b = strconv.AppendUint(b, 1000+uint64(p)%1000, 10)
|
|
b[n] = '.'
|
|
return string(append(b, '%'))
|
|
}
|