golang实现已知三角形三点坐标，求三角形面积

func GetTriangleAreaByVector(x vector.Vector3,y vector.Vector3,z vector.Vector3) float64 {
    //根据三角形三个点坐标求面积
    //先算三角形三个边的长度
    a := vector.GetDistance(x,y)
    b := vector.GetDistance(x,z)
    c := vector.GetDistance(y,z)
    s := (a + b + c) / 2
    area := math.Sqrt(s*(s-a)*(s-b)*(s - c))
    return area
}

//求两点间距离
func GetDistance(a Vector3,b Vector3) float64{
   if a==b {
      return 0
   }else {
      return math.Sqrt(math.Pow(a.X - b.X, 2) + math.Pow(a.Y - b.Y, 2) + math.Pow(a.Z - b.Z, 2))
   }
}

type Vector3 struct {
   X float64    `json:"x"`
   Y float64    `json:"y"`
   Z float64    `json:"z"`
}