| rep {base} | R Documentation |
rep replicates the values in x. It is a generic
function, and the default method is described here.
rep.int is a faster simplified version for the commonest case.
rep(x, times, ...) ## Default S3 method: rep(x, times, length.out, each, ...) rep.int(x, times)
x |
a vector (of any mode including a list) or a pairlist or a
POSIXct or POSIXlt or date object. |
times |
optional non-negative integer. A vector giving the number of
times to repeat each element if of length length(x), or to
repeat the whole vector if of length 1. |
length.out |
optional integer. The desired length of the output vector. |
each |
optional integer. Each element of x is
repeated each times. |
... |
further arguments to be passed to or from other methods. |
A least one of times, length.out and each must be
specified, and normally exactly one is. If length.out is
given, times is ignored. If each is specified with
either of the other two, its replication is performed first, and then
that implied by times or length.out.
If times consists of a single integer,
the result consists of the values in
x repeated this many times.
If times is a vector of the same length as
x, the result consists of x[1]
repeated times[1] times,
x[2] repeated times[2] times and so on.
length.out may be given in place of times,
in which case x is repeated as many times as is
necessary to create a vector of this length.
Non-integer values of times will be truncated towards zero.
If times is a computed quantity it is prudent to add a small fuzz.
If x has length zero and length.out is supplied and is
positive, the values are filled in using the extraction rules, that is
by an NA of the appropriate class for an atomic vector
(0 for raw vectors) and NULL for a list.
A vector of the same class as x.
If the original vector has names, these are also replicated and so will almost always contain duplicates. (In contrast, S strips the names.)
Function rep.int is a simple case handled by internal code, and
provided as a separate function purely for S compatibility.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
rep(1:4, 2) rep(1:4, each = 2) # not the same. rep(1:4, c(2,2,2,2)) # same as second. rep(1:4, c(2,1,2,1)) rep(1:4, each = 2, len = 4) # first 4 only. rep(1:4, each = 2, len = 10) # 8 integers plus two recycled 1's. rep(1:4, each = 2, times = 3) # length 24, 3 complete replications rep(1, 40*(1-.8)) # length 7 on most platforms rep(1, 40*(1-.8)+1e-7) # better ## replicate a list fred <- list(happy = 1:10, name = "squash") rep(fred, 5) # date-time objects x <- .leap.seconds[1:3] rep(x, 2) rep(as.POSIXlt(x), rep(2, 3))