ID EN
Apply Functions

mapply

R Base 3.6.2

mapply is a multivariate version of sapply. mapply applies FUN to the first elements of each … argument, the second elements, the third elements, and so on. Arguments are recycled if necessary.

Syntax

R
mapply(FUN, …, MoreArgs = NULL, SIMPLIFY = TRUE,
       USE.NAMES = TRUE)

Arguments

Parameter Description
FUN function to apply, found via match.fun.
… arguments to vectorize over (vectors or lists of strictly positive length, or all of zero length). See also ‘Details’.
MoreArgs a list of other arguments to FUN.
SIMPLIFY logical or character string; attempt to reduce the result to a vector, matrix or higher dimensional array; see the simplify argument of sapply.
USE.NAMES logical; use names if the first … argument has names, or if it is a character vector, use that character vector as the names.

Return Value

A list, or for SIMPLIFY = TRUE, a vector, array or list.

Details

mapply calls FUN for the values of … (re-cycled to the length of the longest, unless any have length zero), followed by the arguments given in MoreArgs. The arguments in the call will be named if … or MoreArgs are named. Arguments with classes in … will be accepted, and their subsetting and length methods will be used.

Examples

Example
R
# NOT RUN {
mapply(rep, 1:4, 4:1)

mapply(rep, times = 1:4, x = 4:1)

mapply(rep, times = 1:4, MoreArgs = list(x = 42))

mapply(function(x, y) seq_len(x) + y,
       c(a =  1, b = 2, c = 3),  # names from first
       c(A = 10, B = 0, C = -10))

word <- function(C, k) paste(rep.int(C, k), collapse = "")
utils::str(mapply(word, LETTERS[1:6], 6:1, SIMPLIFY = FALSE))
# }

See Also

sapply after which mapply() is modelled. outer which applies a vectorized function to all combinations of two arguments.