Regular Expression with Python

Explore using raw strings in Python for regex patterns, demonstrate a simple pattern like cat for matches, and show how regex engines highlight matches and return start and end ranges.

Apply simple and character-level matching in regex using a sample string, find the range for fox, count occurrences, and match patterns inside braces, showing how metacharacters require backslashes to escape.

The pipe meta character in regular expressions means or, matching either cat or hello, and the engine reports all matches and their positions.

Explore the pipe meta character in regular expressions by solving practice questions that match options like sun or moon, east or west, and morning or evening, while noting case sensitivity.

Explore the dot metacharacter in Python regular expressions, which matches any single character except a newline. It can match letters, spaces, numbers, and symbols, but precise patterns are preferable.

Define a character set with square brackets to match specific characters and ranges, and use caret negation to match anything not in the defined set.

Explore regex patterns with character sets and the dot to match vowels, digits, and uppercase letters; use pipe for John or Tom and caret for negation in the exercise questions.

Learn how quantifiers in regular expressions control repetition of characters, meta characters, and character sets, with practical examples of ?, *, +, and {n,m}.

Explore special sequence characters in regular expressions, including \w, \W, \d, \D, \s, and \S, learn their word, digit, and whitespace patterns, and see practical examples on regex 101.

Practice with ten challenging regex questions using metacharacters and predefined characters learned earlier, applying your knowledge to sample text and boosting confidence in regular expressions.

Explore step-by-step regex solutions in Python for matching dates, alphanumeric identifiers with separators, times, phone numbers, paths, and emails or URLs.

Explore boundary matchers in regex, using caret for line start, dollar for line end, and word boundaries with \b, plus \B, \A, and \Z to mark string positions.

Practice boundary matchers in regular expressions by identifying lines that start or end with patterns, and using word boundaries and anchors such as ^ and $, \A, and \Z.

Learn how to use Python's re module to work with regular expressions, including metacharacters and special sequences. Practice in a Jupyter notebook, leveraging match, search, find all, and compile capabilities.

Use the Python re.match function to identify a pattern at the string's beginning, returning a match object or None and exposing span, start, end, and group details.

Explore using regular expressions with re.match to identify strings that start with Python and filter a list, addressing case sensitivity and the ignore case flag for case-insensitive matches.

Learn how re.search identifies a pattern anywhere in a string and returns the first match. See examples with digits using \d+ and how this contrasts with find all.

Explore the findall method in Python's regex to locate all non-overlapping digit matches in a string, compare it with match and search, and apply it through practical examples.

Learn to use re.findall to extract three-letter words, four-or-more-letter words, and capitalized words from text by crafting patterns and quantifiers.

Use re.compile to create a reusable regex object for efficient repeated pattern matching in Python, then extract the year 1991 from text.

Learn how re.finditer returns match objects with start, end, and span details, enabling precise position tracking for patterns like digits in text, improving on findall.

Use Python's re.finditer to extract word positions in a string, obtaining match objects and spans, demonstrated with the quick brown fox example.

Learn how to split strings with Python's re.split using regex patterns, and modify substrings with re.sub, exploring max splits and pattern customization for flexible text processing.

Explore how re.split with a regex pattern outperforms text split by extracting words from a mixed delimiter string. Build a list of words like apple, banana, orange, grape, cherry.

Learn how to use re.sub to replace digits with a chosen value. See pattern-based substitutions and optional counts with examples masking a phone number and doubling digits.

Apply Python's re.sub to replace temperatures and dates by capturing groups, convert centigrade to Fahrenheit using 9/5*c+32, and reformat dates from m/d/y to y/m/d.

Learn how re.subn differs from sub by returning a tuple of the modified string and the number of replacements, demonstrated by replacing dates with a specific format.