Joins two or more vectors element-wise into a single character vector,
optionally inserting sep between input vectors. If collapse is not NULL,
it will be inserted between elements of the result, returning a character
vector of length 1.
str_c(..., sep = "", collapse = NULL)
| ... | One or more character vectors. Zero length arguments are removed. Short arguments are recycled to the length of the longest. Like most other R functions, missing values are "infectious": whenever
a missing value is combined with another string the result will always
be missing. Use |
|---|---|
| sep | String to insert between input vectors. |
| collapse | Optional string used to combine input vectors into single string. |
If collapse = NULL (the default) a character vector with
length equal to the longest input string. If collapse is
non-NULL, a character vector of length 1.
To understand how str_c works, you need to imagine that you are building up
a matrix of strings. Each input argument forms a column, and is expanded to
the length of the longest argument, using the usual recyling rules. The
sep string is inserted between each column. If collapse is NULL each row
is collapsed into a single string. If non-NULL that string is inserted at
the end of each row, and the entire matrix collapsed to a single string.
paste() for equivalent base R functionality, and
stringi::stri_join() which this function wraps
str_c("Letter: ", letters)#> [1] "Letter: a" "Letter: b" "Letter: c" "Letter: d" "Letter: e" "Letter: f" #> [7] "Letter: g" "Letter: h" "Letter: i" "Letter: j" "Letter: k" "Letter: l" #> [13] "Letter: m" "Letter: n" "Letter: o" "Letter: p" "Letter: q" "Letter: r" #> [19] "Letter: s" "Letter: t" "Letter: u" "Letter: v" "Letter: w" "Letter: x" #> [25] "Letter: y" "Letter: z"str_c("Letter", letters, sep = ": ")#> [1] "Letter: a" "Letter: b" "Letter: c" "Letter: d" "Letter: e" "Letter: f" #> [7] "Letter: g" "Letter: h" "Letter: i" "Letter: j" "Letter: k" "Letter: l" #> [13] "Letter: m" "Letter: n" "Letter: o" "Letter: p" "Letter: q" "Letter: r" #> [19] "Letter: s" "Letter: t" "Letter: u" "Letter: v" "Letter: w" "Letter: x" #> [25] "Letter: y" "Letter: z"str_c(letters, " is for", "...")#> [1] "a is for..." "b is for..." "c is for..." "d is for..." "e is for..." #> [6] "f is for..." "g is for..." "h is for..." "i is for..." "j is for..." #> [11] "k is for..." "l is for..." "m is for..." "n is for..." "o is for..." #> [16] "p is for..." "q is for..." "r is for..." "s is for..." "t is for..." #> [21] "u is for..." "v is for..." "w is for..." "x is for..." "y is for..." #> [26] "z is for..."str_c(letters[-26], " comes before ", letters[-1])#> [1] "a comes before b" "b comes before c" "c comes before d" "d comes before e" #> [5] "e comes before f" "f comes before g" "g comes before h" "h comes before i" #> [9] "i comes before j" "j comes before k" "k comes before l" "l comes before m" #> [13] "m comes before n" "n comes before o" "o comes before p" "p comes before q" #> [17] "q comes before r" "r comes before s" "s comes before t" "t comes before u" #> [21] "u comes before v" "v comes before w" "w comes before x" "x comes before y" #> [25] "y comes before z"str_c(letters, collapse = "")#> [1] "abcdefghijklmnopqrstuvwxyz"str_c(letters, collapse = ", ")#> [1] "a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z"#> [1] "a-d" NA "b-d"#> [1] "a-d" "NA-d" "b-d"