Remove digits between two fullstops

user_9824914 0
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Is there any way to remove digits between two full stops in python?

eg:

  • Input 1: "remove 1 from .1."

  • Output 1: "remove 1 from."

  • Input 2: "XYZ is a student.2. XYZ is a boy.3. XYZ is smart."

  • Output 2: "XYZ is a student. XYZ is a boy. XYZ is smart."

I've tried the following regex but didn't get the preferred output.

output = re.sub(r'([^A-Z].[0-9])+)', input)
python-re digits text python regex
2 Answers

You may try doing a replacement on \s*\.\d+\. and then just replace with single full stop.

inp = ["remove 1 from .1.", "XYZ is a student.2. XYZ is a boy.3. XYZ is smart."]
output = [re.sub(r'\s*\.\d+\.', '.', x) for x in inp]
print(output)

This prints:

['remove 1 from.', 'XYZ is a student. XYZ is a boy. XYZ is smart.']
user_18632290

There are a few noticeable things in your code.

  • Using re.sub requires 3 arguments, where you have provided 2.

  • Avoid naming your variable input

  • The pattern in your example ([^A-Z].[0-9])+) is not a valid pattern as there is an unmatched parenthesis at the end.

If you remove that, you have this pattern [^A-Z].[0-9] which matches a single char other than A-Z, a dot that matches any character and a digit.

That means that the pattern can match a lot more than than intended.

If you don't want to for example change an ip number or a float, you can assert that there is no digit before the match (And note to escape the dot to match it literally)

The pattern is the same as posted by @Tim Biegeleisen only with a leading negative lookbehind to assert no leading digit.

(?<!\d)\s*\.\d+\.

Regex demo

Example

import re

strings = ["remove 1 from .1.", "XYZ is a student.2. XYZ is a boy.3. XYZ is smart.", "test 127.0.0.1 test"]

for s in strings:
    print(re.sub(r'(?<!\d)\s*\.\d+\.', '.', s))

Output

remove 1 from.
XYZ is a student. XYZ is a boy. XYZ is smart.
test 127.0.0.1 test
user_54249880
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