str.replace() v2|v3 does not recognize regular expressions.
To perform a substitution using a regular expression, use re.sub() v2|v3.
For example:
import re
line = re.sub(
r"(?i)^.*interfaceOpDataFile.*$",
"interfaceOpDataFile %s" % fileIn,
line
)
In a loop, it would be better to compile the regular expression first:
import re
regex = re.compile(r"^.*interfaceOpDataFile.*$", re.IGNORECASE)
for line in some_file:
line = regex.sub("interfaceOpDataFile %s" % fileIn, line)
# do something with the updated line
Top answer 1 of 4
750
str.replace() v2|v3 does not recognize regular expressions.
To perform a substitution using a regular expression, use re.sub() v2|v3.
For example:
import re
line = re.sub(
r"(?i)^.*interfaceOpDataFile.*$",
"interfaceOpDataFile %s" % fileIn,
line
)
In a loop, it would be better to compile the regular expression first:
import re
regex = re.compile(r"^.*interfaceOpDataFile.*$", re.IGNORECASE)
for line in some_file:
line = regex.sub("interfaceOpDataFile %s" % fileIn, line)
# do something with the updated line
2 of 4
529
You are looking for the re.sub function.
import re
s = "Example String"
replaced = re.sub('[ES]', 'a', s)
print(replaced)
will print axample atring
Python documentation
docs.python.org › 3 › library › re.html
re — Regular expression operations
May 25, 2026 - Source code: Lib/re/ This module provides regular expression matching operations similar to those found in Perl. Both patterns and strings to be searched can be Unicode strings ( str) as well as 8-...
python - How to input a regex in string.replace? - Stack Overflow
I need some help on declaring a regex. My inputs are like the following: this is a paragraph with in between and then there are cases ... where the number ranges fro... More on stackoverflow.com
String replace method in dart with regex
str.replace(Regex(r"pattern"),"") More on reddit.com
9
3
September 1, 2022How to search for regex and replace with a modified version?
You can pass match object to a function in the replacement section. That function will then do the necessary transformation and return a string. I have a couple of examples here: lambda example function example More on reddit.com
5
3
March 10, 2021Why have to add regex = True to get .replace to work (pandas)
Df["colname"].str.replace("this", "that") This is how it's done More on reddit.com
7
3
March 29, 202203:48
Python re.sub() Tutorial: Text Substitution with Regular Expressions ...
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Replace a String With .replace() (Video) – Real Python
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#78 How to Search and Replace Strings in Python using Regex - YouTube
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Python Regex: How To Replace All Substrings In a String - YouTube
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python regex dynamic replacements (intermediate) anthony explains ...
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How to regex replace and get the number of replacements with ...
Note.nkmk.me
note.nkmk.me › home › python
Replace Strings in Python: replace(), translate(), and Regex
May 4, 2025 - Use the | operator to match multiple patterns. Each pattern may include special regex characters or literal substrings. This allows you to replace different substrings with the same string.
W3Schools
w3schools.com › python › python_regex.asp
Python RegEx
RegEx can be used to check if a string contains the specified search pattern. Python has a built-in package called re, which can be used to work with Regular Expressions.
Flexiple
flexiple.com › python › python-regex-replace
Python regex: How to search and replace strings | Flexiple - Flexiple
To replace a string in Python, the regex sub() method is used. It is a built-in Python method in the re module that returns a replaced string. Don't forget to import the re module.
Pandas
pandas.pydata.org › docs › reference › api › pandas.Series.str.replace.html
pandas.Series.str.replace — pandas 3.0.5 documentation
Method to replace occurrences of a substring with another substring. ... Extract substrings using a regular expression. ... Find all occurrences of a pattern or regex in each string.
Top answer 1 of 7
881
This tested snippet should do it:
import re
line = re.sub(r"</?\[\d+>", "", line)
Edit: Here's a commented version explaining how it works:
line = re.sub(r"""
(?x) # Use free-spacing mode.
< # Match a literal '<'
/? # Optionally match a '/'
\[ # Match a literal '['
\d+ # Match one or more digits
> # Match a literal '>'
""", "", line)
Regexes are fun! But I would strongly recommend spending an hour or two studying the basics. For starters, you need to learn which characters are special: "metacharacters" which need to be escaped (i.e. with a backslash placed in front - and the rules are different inside and outside character classes.) There is an excellent online tutorial at: www.regular-expressions.info. The time you spend there will pay for itself many times over. Happy regexing!
2 of 7
66
str.replace() does fixed replacements. Use re.sub() instead.
GeeksforGeeks
geeksforgeeks.org › python › python-substituting-patterns-in-text-using-regex
Python - Substituting patterns in text using regex - GeeksforGeeks
July 12, 2025 - # Python implementation of substituting a # specific text pattern in a string using regex # importing regex module import re # Function to perform # operations on the strings def substitutor(): # a string variable sentence1 = "It is raining outside." # replacing text 'raining' in the string # variable sentence1 with 'sunny' thus # passing first parameter as raining # second as sunny, third as the # variable name in which string is stored # and printing the modified string print(re.sub(r"raining", "sunny", sentence1)) # a string variable sentence2 = "Thank you very very much."
Plain English
python.plainenglish.io › the-incredible-power-of-pythons-replace-regex-6cc217643f37
The incredible power of Python’s replace regex | by Josh Weinstein | Python in Plain English
November 1, 2020 - The replacement string can be a literal replacement, such as matching [0-9]+ and replacing it with "abc" . Such an operation would convert all digit sequences in a string with the character sequence "abc" .
PYnative
pynative.com › home › python › regex › python regex replace pattern in a string using re.sub()
Python Regex Replace Pattern in a string using re.sub()
July 19, 2021 - import re # replacement function to convert uppercase letter to lowercase def convert_to_lower(match_obj): if match_obj.group() is not None: return match_obj.group().lower() # Original String str = "Emma LOves PINEAPPLE DEssert and COCONUT Ice Cream" # pass replacement function to re.sub() res_str = re.sub(r"[A-Z]", convert_to_lower, str) # String after replacement print(res_str) # Output 'Emma loves pineapple dessert and coconut Ice Cream'Code language: Python (python) Run · We saw how to find and replace the single regex pattern in the earlier examples.
Python documentation
docs.python.org › 3 › howto › regex.html
Regular expression HOWTO — Python 3.14.6 documentation
If the pattern isn’t found, string is returned unchanged. The optional argument count is the maximum number of pattern occurrences to be replaced; count must be a non-negative integer.
W3Schools
w3schools.com › python › ref_string_replace.asp
Python String replace() Method
Remove List Duplicates Reverse ... Q&A Python Bootcamp Python Training ... The replace() method replaces a specified phrase with another specified phrase....
PythonTest
pythontest.com › python › regex-search-replace
Python regex Search and Replace Examples | PythonTest
I think the most basic form of ... care of the stream verses filename input handling. The re (regex, regular expression) module has sub which handles the search/replace....
TechGeekBuzz
techgeekbuzz.com › blog › python-regex-replace-pattern-in-a-string-using-re-sub
Python Regex Replace Pattern in a string using re.sub()
To do this, we learned two regex methods sub() and subn() . The sub() method accept a regular expression pattern, and replace all the matched pattern of the string with the replacement string or function, and return the newly replaced string.
GeeksforGeeks
geeksforgeeks.org › python › python-regex-replace-captured-groups
Python Regex: Replace Captured Groups - GeeksforGeeks
July 23, 2025 - This article dives into one of the crucial aspects of regex in Python: Regex Groups, and demonstrates how to use `re.sub()` for group replacement with practical examples. A group in regex is a part of a pattern that is enclosed in parentheses. Groups allow us to segment a pattern into sub-patterns, making it easier to apply specific operations on each part. These groups are indexed numerically from 1 for the first group and so on. The entire match is group 0. ... Extract parts of the matched string: If we want to extract or capture a specific part of the text that matches the pattern, groups allow us to do this.
Real Python
realpython.com › replace-string-python
How to Replace a String in Python – Real Python
January 15, 2025 - In this tutorial, you'll learn how to remove or replace a string or substring. You'll go from the basic string method .replace() all the way up to a multi-layer regex pattern using the sub() function from Python's re module.
Index.dev
index.dev › blog › regex-advanced-string-replacement-python
Python Regex Replace: How to Replace Strings Using re Module
The re.sub() function is the primary tool for performing string replacements with regex in Python. It allows you to specify a regex pattern to search for, a replacement string, and the target string where the replacement will occur.
Table Convert
tableconvert.com › home › table convert
Table Convert - Free Online Table Converter and Generator
July 28, 2025 - Edit data using our advanced online table editor with professional features. Supports deleting empty rows, removing duplicates, data transposition, sorting, regex find & replace, and real-time preview.
RegExr
regexr.com
RegExr: Learn, Build, & Test RegEx
RegExr is an online tool to learn, build, & test Regular Expressions (RegEx / RegExp).
freeCodeCamp
freecodecamp.org › news › javascript-string-replace-example-with-regex
JavaScript String.Replace() Example with RegEx
October 20, 2020 - As you can see above, the replace method accepts two arguments: the string to be replaced, and what the string would be replaced with. Here is where Regex comes in.