promql/functions.go
func funcStddevOverTime(vals []Value, args Expressions, enh *EvalNodeHelper) Vector {
	return aggrOverTime(vals, enh, func(values []Point) float64 {
		var aux, count, mean float64
		for _, v := range values {
			count++
			delta := v.V - mean
			mean += delta / count
			aux += delta * (v.V - mean)
		}
		return math.Sqrt(aux / count)
	})
}
func funcStddevOverTime(vals []Value, args Expressions, enh *EvalNodeHelper) Vector {
	return aggrOverTime(vals, enh, func(values []Point) float64 {
		var aux, count, mean float64
		for _, v := range values {
			count++
			delta := v.V - mean
			mean += delta / count
			aux += delta * (v.V - mean)
		}
		return math.Sqrt(aux / count)
	})
}
func funcStddevOverTime ( vals [ ] Value , args Expressions , enh * EvalNodeHelper ) Vector { return aggrOverTime ( vals , enh , func ( values [ ] Point ) float64 { var aux , count , mean float64 for _ , v := range values { count ++ delta := v . V - mean mean += delta / count aux += delta * ( v . V - mean ) } return math . Sqrt ( aux / count ) } ) }
// === stddev_over_time(Matrix ValueTypeMatrix) Vector ===
=== stddev_over_time ( Matrix ValueTypeMatrix ) Vector ===