TypeError：+：＆＃39; int＆＃39;不支持的操作数类型和＆＃39; str＆＃39;： - 返回总和（数字）/浮点数（len（数字））

Question

下面是我的代码，它给我这样的错误 TypeError：+：＆＃39; int＆＃39;不支持的操作数类型和＆＃39; str＆＃39;

def mean(numbers):
  return sum(numbers) / float(len(numbers))
def stdev(numbers):
  avg = mean(numbers)
  variance = sum([pow(x - avg, 2) for x in numbers]) / float(len(numbers) - 1)
return math.sqrt(variance)

我试着像这样改变它

 def mean(numbers):
  return sum([int(numbers)]) / float(len(numbers))
def stdev(numbers):
  avg = mean(numbers)
  variance = sum([pow(x - avg, 2) for x in numbers]) / float(len(numbers) - 1)
return math.sqrt(variance)

但是这次它给了我这个错误 TypeError：int（）参数必须是字符串，类字节对象或数字，而不是＆＃39;元组＆＃39;

Answer 1

将您的第一个功能更改为

def mean(numbers):
  return sum([int(x) for x in numbers]) / float(len(numbers))