R: Detect the presence or absence of a pattern in a string.

str_detect {stringr} | R Documentation

## Detect the presence or absence of a pattern in a string.

### Description

Vectorised over `string` and `pattern`.

### Usage

    str_detect(string, pattern)

### Arguments

`string` | Input vector. Either a character vector, or something coercible to one.
`pattern` | Pattern to look for. The default interpretation is a regular expression, as described in stringi::stringi-search-regex. Control options with `regex()`. Match a fixed string (i.e. by comparing only bytes), using `fixed()`. This is fast, but approximate. Generally, for matching human text, you'll want `coll()` which respects character matching rules for the specified locale. Match character, word, line and sentence boundaries with `boundary()`. An empty pattern, "", is equivalent to `boundary("character")`.

### Value

A logical vector.

### See Also

`stringi::stri_detect()` which this function wraps, `str_subset()` for a convenient wrapper around `x[str_detect(x, pattern)]`

### Examples

    fruit <- c("apple", "banana", "pear", "pinapple")
    str_detect(fruit, "a")
    str_detect(fruit, "^a")
    str_detect(fruit, "a$")
    str_detect(fruit, "b")
    str_detect(fruit, "[aeiou]")

    # Also vectorised over pattern
    str_detect("aecfg", letters)

[Package stringr version 1.3.1 Index]