Count number of matches

Counts the number of times pattern is found within each element of string.

Usage

str_count(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 vignette("regular-expressions"). Use regex() for finer control of the matching behaviour.

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(). The empty string, ""``, is equivalent to boundary("character")`.

Value

An integer vector the same length as string/pattern.

See also

stringi::stri_count() which this function wraps.

str_locate()/str_locate_all() to locate position of matches

Examples

fruit <- c("apple", "banana", "pear", "pineapple")
str_count(fruit, "a")
#> [1] 1 3 1 1
str_count(fruit, "p")
#> [1] 2 0 1 3
str_count(fruit, "e")
#> [1] 1 0 1 2
str_count(fruit, c("a", "b", "p", "p"))
#> [1] 1 1 1 3

str_count(c("a.", "...", ".a.a"), ".")
#> [1] 2 3 4
str_count(c("a.", "...", ".a.a"), fixed("."))
#> [1] 1 3 2