57 lines
1.1 KiB
Go
57 lines
1.1 KiB
Go
package main
|
|
|
|
import (
|
|
"fmt"
|
|
"math"
|
|
)
|
|
|
|
var _ = fmt.Print
|
|
|
|
const initialLength int = 1024
|
|
const verySmall float64 = -100000
|
|
const veryBig float64 = 100000
|
|
|
|
type Stats struct {
|
|
Mean float64 `json:"mean"`
|
|
Var float64 `json:"var"`
|
|
Std float64 `json:"std"`
|
|
}
|
|
|
|
type StatAggregator struct {
|
|
sum float64
|
|
sumOfTheSquares float64
|
|
n int
|
|
histogram []float64
|
|
min float64
|
|
max float64
|
|
}
|
|
|
|
func NewStatAggregator() *StatAggregator {
|
|
return &StatAggregator{0, 0, 0, make([]float64, initialLength), veryBig, verySmall}
|
|
}
|
|
|
|
func (this *StatAggregator) AddStats(dataChannel chan float64, output chan *Stats) {
|
|
for datum := range dataChannel {
|
|
this.sum += datum
|
|
this.sumOfTheSquares += datum * datum
|
|
this.n += 1
|
|
if datum < this.min {
|
|
this.min = datum
|
|
}
|
|
if datum > this.max {
|
|
this.max = datum
|
|
}
|
|
}
|
|
output <- this.getFinalStats()
|
|
}
|
|
|
|
func (this *StatAggregator) getFinalStats() *Stats {
|
|
stats := new(Stats)
|
|
stats.Mean = this.sum / float64(this.n)
|
|
stats.Var = this.sumOfTheSquares/float64(this.n) - stats.Mean*stats.Mean
|
|
stats.Std = math.Sqrt(stats.Var)
|
|
|
|
return stats
|
|
|
|
}
|