regexp:
Match regular expression
Description
Returns the positions of substrings that match the regular expression.
Usage
regexp(s, pat, ignorecase = FALSE, once = FALSE, split = FALSE)
regexpi(s, pat, once = FALSE, split = FALSE)
Arguments
s
Character string, i.e. of length 1.
pat
Matching pattern as character string.
ignorecase
Logical: whether case should be ignored;
default: FALSE.
once
Logical: whether the first are all occurrences should be found;
default: all.
split
Logical: should the string be splitted at the occurrences of
the pattern?; default: no.
Value
A list with components start and end as numeric vectors
indicating the start and end positions of the matches.match contains each exact match, and split contains the
character vector of splitted strings.If no match is found all components will be NULL, except
split that will contain the whole string if split = TRUE.
Details
Returns the start and end positions and the exact value of substrings
that match the regular expression. If split is choosen, the
splitted strings will also be returned.
Examples
s <- "bat cat can car COAT court cut ct CAT-scan"
pat <- 'c[aeiou]+t'
regexp(s, pat)
regexpi(s, pat)