github.com/songzhibin97/gkit@v1.2.13/internal/stat/reduce.go

package stat

// Sum 返回窗口所有值之和
func Sum(iterator Iterator) float64 {
	result := 0.0
	for iterator.Next() {
		bucket := iterator.Bucket()
		for _, p := range bucket.Points {
			result = result + p
		}
	}
	return result
}

// Avg 返回窗口平均值
func Avg(iterator Iterator) float64 {
	result := 0.0
	count := 0.0
	for iterator.Next() {
		bucket := iterator.Bucket()
		for _, p := range bucket.Points {
			result = result + p
			count = count + 1
		}
	}
	return result / count
}

// Min 返回窗口最小值
func Min(iterator Iterator) float64 {
	result := 0.0
	started := false
	for iterator.Next() {
		bucket := iterator.Bucket()
		for _, p := range bucket.Points {
			if !started {
				result = p
				started = true
				continue
			}
			if p < result {
				result = p
			}
		}
	}
	return result
}

// Max 返回窗口最大值
func Max(iterator Iterator) float64 {
	result := 0.0
	started := false
	for iterator.Next() {
		bucket := iterator.Bucket()
		for _, p := range bucket.Points {
			if !started {
				result = p
				started = true
				continue
			}
			if p > result {
				result = p
			}
		}
	}
	return result
}

// Count 返回窗口中的 key
func Count(iterator Iterator) float64 {
	var result int64
	for iterator.Next() {
		bucket := iterator.Bucket()
		result += bucket.Count
	}
	return float64(result)
}