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pythonstringintegerbooleandigit

Python string functions

How can I determine if a string can be an integer in Python. For example: if I write functions named digit() and nondigit(). The string must be either just digits (1-9) or letters.

str1 = '4582'
str1.digit() == True
str2 = '458dfr'
str2.digit() == False
str3 = 'abcd'
str3.nondigit() == True
str4 = '258edcx'
str4.nondigit() == False
Solution

  • str objects have an isdigit method which accomplishes one of your tasks. From a broader perspective, it's better to just try it and see:

    def digit(s):
    try:
        int(s)
        return True
    except ValueError:
        return False

    For example, " 1234 ".isdigit() is False (there are spaces), but python can convert it to an int, so my digit function is True.