regex_numbers {doseminer} | R Documentation |
Regular expression to match numbers in English
Description
A regex pattern to identify natural language English number phrases, such as
"one hundred and fifty" or "thirty-seven". Used internally by
replace_numbers
to identify substrings to replace with their
decimal representation.
Usage
regex_numbers
Format
An object of class character
of length 1.
Details
This is a PCRE (Perl type) regular expression, so it must be used with
perl = TRUE
in base R regex functions. The packages stringr
and stringi
are based on the alternative ICU regular expression
engine, so they cannot use this pattern.
Note
There is limited support for fractional expressions like "one half". The original pattern did not support expressions like "a thousand", but it has been adapted to offer (experimental) support for this. Phrases like "million" or "thousand" with no prefix will not match.
Source
https://www.rexegg.com/regex-trick-numbers-in-english.html