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stringr (version 0.6.2)

str_extract: Extract first piece of a string that matches a pattern.

Description

Vectorised over string. pattern should be a single pattern, i.e. a character vector of length one.

Usage

str_extract(string, pattern)

Arguments

string
input vector. This must be an atomic vector, and will be coerced to a character vector
pattern
pattern to look for, as defined by a POSIX regular expression. See the ``Extended Regular Expressions'' section of regex for details. See fixed,

Value

  • character vector.

See Also

str_extract_all to extract all matches

Examples

Run this code
shopping_list <- c("apples x4", "flour", "sugar", "milk x2")
str_extract(shopping_list, "\\d")
str_extract(shopping_list, "[a-z]+")
str_extract(shopping_list, "[a-z]{1,4}")
str_extract(shopping_list, "\\b[a-z]{1,4}\\b")

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