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So, as an example, let’s say that there is only one line of code in the program, and that line of code is n = input(), and let’s say that the user inputted random123. How can I make it so when I print n, it only prints the integers of n, or 123? Note that I want this to work even if the user input is random123random456. If the user input IS “random123random456,” I want it to print 123456.

thatonehayk
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3 Answers3

4

You can use a generator expression with a call to the str.isdigit method as a filter:

''.join(c for c in n if c.isdigit())
blhsing
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1

Another quick way is to remove any non numeric character from the string with regular expressions

Example:

import re
test = "123string456"

result = re.sub('\D', '', test)

Here \D means any character different from 0...9 You can then replace it with empty character

Some results:

>>> import re
>>> re.sub('\D', '', 'random123random456')
'123456'
>>> re.sub('\D', '', 'random123')
'123'

Best regards

manuel_b
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0
test = "123string456"
output = str()
for each in test:
    try:
        n = int(each)
        output = "{}{}".format(output,n)
    except:
        pass

print(output)
ap288
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    I would strongly recommend replacing `except:` with `except ValueError:`. See [What is wrong with using a bare 'except'?](https://stackoverflow.com/questions/54948548/what-is-wrong-with-using-a-bare-except). – Xukrao Mar 11 '19 at 01:06