Day 1: Standard Deviation (표준편차)

HackerRank 10 days of statics

Day 1 note taking: Standard Deviation

Standard Deviation (표준편차):  The average distance to the mean. (Square root of variance)

   모든 원소 x의 평균 m에 대한 평균거리. (분산의 제곱근)

Variance (분산) = The average magnitude of fluctuations of from its expected value. (Standard Deviation)^2

 확률변수x들과 기댓값(평균값) m간의 평균 변동 크기. (표준편차)^2

#python 3
import math

def StandardDeviation(n, arr):
    mu = sum(arr)/n
    variance = sum([((x - mu) ** 2) for x in arr]) / n
    print (round(math.sqrt(variance),1))

if __name__ == '__main__':
    n = int(input())
    arr_item = list(map(int, input().split()))
    StandardDeviation(n,arr_item)