A function that matches patterns and returns a logical vector
Usage
sf_grepl(subject, pattern, encode_mode = "auto", fixed = FALSE,
nthreads = getOption("stringfish.nthreads", 1L))Arguments
- subject
The subject character vector to search
- pattern
The pattern to search for
- encode_mode
"auto", "UTF-8" or "byte". Determines multi-byte (UTF-8) characters or single-byte characters are used.
- fixed
determines whether the pattern parameter should be interpreted literally or as a regular expression
- nthreads
Number of threads to use
Details
The function uses the PCRE2 library, which is also used internally by R. The encoding is based on the pattern string (or forced via the encode_mode parameter). Note: the order of paramters is switched compared to the `grepl` base R function, with subject being first. See also: https://www.pcre.org/current/doc/html/pcre2api.html for more documentation on match syntax.
Examples
if(getRversion() >= "3.5.0") {
x <- sf_vector(10)
sf_assign(x, 1, "hello world")
pattern <- "^hello"
sf_grepl(x, pattern)
}
#> [1] TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE