Regex in MATLAB

Regular expressions (regex) are a powerful tool used for text processing, searching, and manipulation. MATLAB has regular expression capabilities built into many of its built-in functions, including regexp, regexprep, and regexpi.

Here are some examples on how to use regex in MATLAB:

1. regexp: The regexp function searches a string for a specified pattern and returns the starting and ending indices of all occurrences of the pattern. For example:

str = 'The quick brown fox jumps over the lazy dog.'
pattern = '\w+'  % matches any word character
indices = regexp(str, pattern)

2. regexprep: The regexprep function replaces one or more occurrences of a pattern in a string with a specified string. For example:

str = 'The quick brown fox jumps over the lazy dog.'
pattern = '\s+'  % matches any whitespace character
replace = ', '
new_str = regexprep(str, pattern, replace)

In this example, new_str will be the same as the original string, but with every instance of whitespace replaced with a comma and a space.

3. regexpi: The regexpi function is similar regexp, but performs a case-insensitive search. For example:

str = 'The quick brown fox jumps over the lazy dog.'
pattern = 'fox'
indices = regexpi(str, pattern)

In this example, indices will be a matrix containing the starting and ending indices of the word "fox" in the string, regardless of whether it is capitalized or lowercase.

These are just a few examples of how to use regex in MATLAB. Regular expressions can be incredibly powerful for text processing and manipulation, and it is important to familiarize yourself with the syntax and capabilities of regular expressions if you want to master text-related tasks in MATLAB.