math - 如何从golang中的数组中获取偏度值

Question

我想在 golang 中获得数学统计的偏度和峰度。但是我在golang中找不到任何外部包。

我在 github 站点中找到了 JavaScript 的偏度函数。但是这个函数的值与 R 示例代码不同....

包主


进口 （
    “fmt”
    “数学”
)

功能主要（）{
    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}
    获取偏度（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