sjmisc: str_start – R documentation

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str_start

Find start and end index of pattern in string

Description

str_start() finds the beginning position of pattern in each element of x, while str_end() finds the stopping position of pattern in each element of x.

Usage

str_start(x, pattern, ignore.case = TRUE, regex = FALSE)

str_end(x, pattern, ignore.case = TRUE, regex = FALSE)

Arguments

`x`	A character vector.
`pattern`	Character string to be matched in `x`. `pattern` might also be a regular-expression object, as returned by `stringr::regex()`. Alternatively, use `regex = TRUE` to treat `pattern` as a regular expression rather than a fixed string.
`ignore.case`	Logical, whether matching should be case sensitive or not. `ignore.case` is ignored when `pattern` is no regular expression or `regex = FALSE`.
`regex`	Logical, if `TRUE`, `pattern` is treated as a regular expression rather than a fixed string.

Value

A numeric vector with index of start/end position(s) of pattern found in x, or -1, if pattern was not found in x.

Examples

path <- "this/is/my/fileofinterest.csv"
str_start(path, "/")

path <- "this//is//my//fileofinterest.csv"
str_start(path, "//")
str_end(path, "//")

x <- c("my_friend_likes me", "your_friend likes_you")
str_start(x, "_")

# pattern "likes" starts at position 11 in first, and
# position 13 in second string
str_start(x, "likes")

# pattern "likes" ends at position 15 in first, and
# position 17 in second string
str_end(x, "likes")

x <- c("I like to move it, move it", "You like to move it")
str_start(x, "move")
str_end(x, "move")

x <- c("test1234testagain")
str_start(x, "\\d+4")
str_start(x, "\\d+4", regex = TRUE)
str_end(x, "\\d+4", regex = TRUE)

sjmisc

Data and Variable Transformation Functions

v2.8.6

GPL-3

Authors

Daniel Lüdecke [aut, cre] (<https://orcid.org/0000-0002-8895-3206>), Iago Giné-Vázquez [ctb], Alexander Bartel [ctb] (<https://orcid.org/0000-0002-1280-6138>)

Initial release