This is a convenience function to capture substrings from textual data.
str_match_all internally but instead of returning everything, always returns only one single part of the match, depending on parameters
extract_substring( string, pattern, capture_n = 1, capture_bracket = 0, missing = NA_character_ )
string to extract
regular expression pattern to search for
within each string, which match of the
for the captured match, which capture group should be extracted? i.e. which parentheses-enclosed segment of the
what to replace missing values with? Note that values can be missing because there are not enough captured matches or because the actual capture_bracket is empty.
character vector of same length as
string with the extracted substrings