How to make a raw input a number?

This question already has an answer here:

How can I convert a string to an int in Python? 7 answers

How do I parse a string to a float or int in Python? 22 answers

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times = int(raw_input('Enter a number: '))

If someone enters in something other than an integer, it will throw an exception. If that's not what you want, you could catch the exception and handle it yourself, like this:

try:
    times = int(raw_input('Enter a number: '))
except ValueError:
    print "An integer is required."

If you want to keep asking for input until someone enters a valid input, put the above in a while loop:

while True:
    try:
        times = int(raw_input('Enter a number: '))
        break
    except ValueError:
        print "An integer is required."

---

Wrap your input in int or float depending on the data type you are expecting.

times = int(raw_input('Enter a number: '))
print type(times)

Outputs:

Enter a number:  10
<type 'int'>

If a user inputs something other than a number, it will throw a ValueError (for example, inputing asdf results in:)

ValueError: invalid literal for int() with base 10: 'asdf'

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您可以将输入转换为整数，如果不是，则捕获异常：

try:
    times = int(raw_input('Enter a number: '))
    # do something with the int
except ValueError:
    # not an int
    print 'Not an integer'

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