python求平均数、方差、中位数的例子

CalStatistics.py

def getNum():       #获取用户不定长度的输入
 nums = []
 iNumStr = input("请输入数字(回车退出):")
 while iNumStr != "":
   nums.append(eval(iNumStr))
   iNumStr = input("请输入数学(回车退出):")
 return nums

def mean(numbers):     #计算平均值
 s = 0.0
 for num in numbers:
   s = s + num
 return s/len(numbers)

def dev(numbers, mean):  #计算方差
 sdev = 0.0
 for num in numbers:
   sdev = sdev + (num - mean)**2
 return pow(sdev / (len(numbers)-1), 0.5)

def median(numbers):    #计算中位数
 numbers = sorted(numbers)    #sorted(numbers)
 size = len(numbers)
 if size ％ 2 == 0:
   med = (numbers[size//2 - 1] + numbers[size//2])/2
 else:
   med = numbers[size//2]
 return med

n = getNum()
m = mean(n)
print("平均值:{},方差:{:.2},中位数:{}.".format(m, dev(n,m), median(n)))

来源：https://blog.csdn.net/JessiFan/article/details/82428404