将原始输入变量除以numb时出现Python TypeError

Question

我想把输入的磅重量转换成公斤，我得到以下错误。。。在

TypeError: unsupported operand type(s) for /: 'unicode' and 'float'

我的代码：

lbweight = raw_input("Current Weight (lb): ") 

kgweight = lbweight/2.20462

有人请帮忙！在

Answer 1

这是因为使用raw_input，输入是raw，表示一个字符串：

lbweight = float(raw_input("Current Weight (lb): ") )

kgweight = lbweight/2.20462

Answer 2

raw_input返回一个字符串，应使用float()将输入转换为float：

float(raw_input("Current Weight (lb): "))

Answer 3

注意错误消息TypeError: unsupported operand type(s) for /: 'str' and 'float'

>>> kgweight = lbweight/2.20462

Traceback (most recent call last):
  File "<pyshell#17>", line 1, in <module>
    kgweight = lbweight/2.20462
TypeError: unsupported operand type(s) for /: 'str' and 'float'
>>> 

如果2.20462是一个浮点数，那么这里哪一个是字符串？文档对raw_input说了些什么？在

If the prompt argument is present, it is written to standard output without a trailing newline. The function then reads a line from input, converts it to a string (stripping a trailing newline), and returns that. When EOF is read, EOFError is raised.