iedc-go/vendor/github.com/montanaflynn/stats/mean.go
2022-10-19 21:32:34 +08:00

61 lines
1.1 KiB
Go

package stats
import "math"
// Mean gets the average of a slice of numbers
func Mean(input Float64Data) (float64, error) {
if input.Len() == 0 {
return math.NaN(), EmptyInput
}
sum, _ := input.Sum()
return sum / float64(input.Len()), nil
}
// GeometricMean gets the geometric mean for a slice of numbers
func GeometricMean(input Float64Data) (float64, error) {
l := input.Len()
if l == 0 {
return math.NaN(), EmptyInput
}
// Get the product of all the numbers
var p float64
for _, n := range input {
if p == 0 {
p = n
} else {
p *= n
}
}
// Calculate the geometric mean
return math.Pow(p, 1/float64(l)), nil
}
// HarmonicMean gets the harmonic mean for a slice of numbers
func HarmonicMean(input Float64Data) (float64, error) {
l := input.Len()
if l == 0 {
return math.NaN(), EmptyInput
}
// Get the sum of all the numbers reciprocals and return an
// error for values that cannot be included in harmonic mean
var p float64
for _, n := range input {
if n < 0 {
return math.NaN(), NegativeErr
} else if n == 0 {
return math.NaN(), ZeroErr
}
p += (1 / n)
}
return float64(l) / p, nil
}