如何从golang中的数组获取偏度值

Question

I want to get skewness and kurtosis of math statistics in golang. But I can't find any external package in golang.

I found the skewness function of a JavaScript in github site. But the value of this function is different to R example code....

package main

import (
    "fmt"
    "math"
)

func main() {
    arr := []float64{19.09, 19.55, 17.89, 17.73, 25.15, 27.27, 25.24, 21.05, 21.65, 20.92, 22.61, 15.71, 22.04, 22.60, 24.25}
    getSkewness(arr)
}
func getSkewness(arr []float64) {

var delta, n, delta_n, term1, mean, m2, m3 float64
for _, v := range arr {
    n += 1

    delta = v - mean
    delta_n = delta / n

    term1 = delta * delta_n * (n - 1)

    m3 += term1*delta_n*(n-2) - 3*delta_n*m2
    m2 += term1
    mean += delta_n
}
g := math.Sqrt(n) * m3 / math.Pow(m2, 3/2)
result := math.Sqrt(n*n-1) * g / (n - 2)
fmt.Println(result)
}

Answer 1

Take a look at: stat, it has both skewness and kurtosis implemented, simple as:

arr := stat.Float64Slice{19.09, 19.55, 17.89, 17.73, 25.15, 27.27, 25.24, 21.05, 21.65, 20.92, 22.61, 15.71, 22.04, 22.60, 24.25}
fmt.Println("Skewness -> ", stat.Skew(arr))
fmt.Println("Kurtosis -> ", stat.Kurtosis(arr))

and the results:

Skewness ->  -0.014112840588657319
Kurtosis ->  -0.9955286230856646