Split up a string into pieces.

Vectorised over string and pattern.

Usage

str_split(string, pattern, n = Inf, simplify = FALSE)

str_split_fixed(string, pattern, n)

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").

n

number of pieces to return. Default (Inf) uses all possible split positions.

For str_split_fixed, if n is greater than the number of pieces, the result will be padded with empty strings.

simplify

If FALSE, the default, returns a list of character vectors. If TRUE returns a character matrix.

Value

For str_split_fixed, a character matrix with n columns. For str_split, a list of character vectors.

See also

stri_split() for the underlying implementation.

Examples

fruits <- c(
  "apples and oranges and pears and bananas",
  "pineapples and mangos and guavas"
)

str_split(fruits, " and ")
#> [[1]]
#> [1] "apples"  "oranges" "pears"   "bananas"
#> 
#> [[2]]
#> [1] "pineapples" "mangos"     "guavas"    
#> 
str_split(fruits, " and ", simplify = TRUE)
#>      [,1]         [,2]      [,3]     [,4]     
#> [1,] "apples"     "oranges" "pears"  "bananas"
#> [2,] "pineapples" "mangos"  "guavas" ""       

# Specify n to restrict the number of possible matches
str_split(fruits, " and ", n = 3)
#> [[1]]
#> [1] "apples"            "oranges"           "pears and bananas"
#> 
#> [[2]]
#> [1] "pineapples" "mangos"     "guavas"    
#> 
str_split(fruits, " and ", n = 2)
#> [[1]]
#> [1] "apples"                        "oranges and pears and bananas"
#> 
#> [[2]]
#> [1] "pineapples"        "mangos and guavas"
#> 
# If n greater than number of pieces, no padding occurs
str_split(fruits, " and ", n = 5)
#> [[1]]
#> [1] "apples"  "oranges" "pears"   "bananas"
#> 
#> [[2]]
#> [1] "pineapples" "mangos"     "guavas"    
#> 

# Use fixed to return a character matrix
str_split_fixed(fruits, " and ", 3)
#>      [,1]         [,2]      [,3]               
#> [1,] "apples"     "oranges" "pears and bananas"
#> [2,] "pineapples" "mangos"  "guavas"           
str_split_fixed(fruits, " and ", 4)
#>      [,1]         [,2]      [,3]     [,4]     
#> [1,] "apples"     "oranges" "pears"  "bananas"
#> [2,] "pineapples" "mangos"  "guavas" ""