\Header{rep}{Replicate Elements of Vectors and Lists}
\methalias{rep.int}{rep}
\keyword{manip}{rep}
\begin{Description}\relax
\code{rep} replicates the values in \code{x}
according to the values given in \code{times}
and \code{length.out}.\end{Description}
\begin{Usage}
\begin{verbatim}
rep(x, times, length.out, each)
rep.int(x, times)
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{x}] a vector (of any mode including a list) or a pairlist.
\item[\code{times}] integer.  A vector giving the number of times to repeat
each element if of length \code{length(x)}, or to repeat the whole
vector if of length 1.
\item[\code{length.out}] integer.  (Optional.)  The desired length of the
output vector.
\item[\code{each}] optional integer. Each element of \code{x} is
repeated \code{each} times.
\end{ldescription}
\end{Arguments}
\begin{Details}\relax
If \code{times} consists of a single integer,
the result consists of the values in
\code{x} repeated this many times.
If \code{times} is a vector of the same length as
\code{x}, the result consists of \code{x[1]}
repeated \code{times[1]} times,
\code{x[2]} repeated \code{times[2]} times and so on.

\code{length.out} may be given in place of \code{times},
in which case \code{x} is repeated as many times as is
necessary to create a vector of this length.  If both
\code{length.out} and \code{times} are specified, \code{times}
determines the replication, and \code{length.out} can be used to
truncate the output vector (or extend it by \code{NA}s).

Non-integer values of \code{times} will be truncated towards zero.
If \code{times} is a computed quantity it is prudent to add a small fuzz.\end{Details}
\begin{Note}\relax
If the original vector has names, these are also replicated and so
will almost always contain duplicates.

If \code{length.out} is used to extend the vector, the behaviour is
different from that of S-PLUS, which recycles the existing vector.

Function \code{rep.int} is a simple case handled by internal code, and
provided as a separate function purely for S compatibility.\end{Note}
\begin{SeeAlso}\relax
\code{\Link{seq}}, \code{\Link{sequence}}.\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
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 NAs

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)
\end{ExampleCode}
\end{Examples}

