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-search-regex. Control options with regex().

Match a fixed string (i.e. by comparing only bytes), using fixed(x). This is fast, but approximate. Generally, for matching human text, you'll want coll(x) 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.

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)