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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/parallelMap.R
\name{parallelMap}
\alias{parallelMap}
\title{Maps a function over lists or vectors in parallel.}
\usage{
parallelMap(
fun,
...,
more.args = list(),
simplify = FALSE,
use.names = FALSE,
impute.error = NULL,
level = NA_character_,
show.info = NA
)
}
\arguments{
\item{fun}{\link{function}\cr
Function to map over \code{...}.}
\item{...}{(any)\cr
Arguments to vectorize over (list or vector).}
\item{more.args}{\link{list}\cr
A list of other arguments passed to \code{fun}.
Default is empty list.}
\item{simplify}{(\code{logical(1)})\cr
Should the result be simplified? See \link{simplify2array}. If \code{TRUE},
\code{simplify2array(higher = TRUE)} will be called on the result object.
Default is \code{FALSE}.}
\item{use.names}{(\code{logical(1)})\cr
Should result be named?
Use names if the first \code{...} argument has names, or if it is a
character vector, use that character vector as the names.}
\item{impute.error}{(\code{NULL} | \verb{function(x)})\cr
This argument can be used for improved error handling. \code{NULL} means that,
if an exception is generated on one of the slaves, it is also thrown on the
master. Usually all slave jobs will have to terminate until this exception
on the master can be thrown. If you pass a constant value or a function,
all jobs are guaranteed to return a result object, without generating an
exception on the master for slave errors. In case of an error, this is a
\code{\link[=simpleError]{simpleError()}} object containing the error message. If you passed a
constant object, the error-objects will be substituted with this object. If
you passed a function, it will be used to operate on these error-objects
(it will ONLY be applied to the error results). For example, using
\code{identity} would keep and return the \code{simpleError}-object, or \code{function(x) 99} would impute a constant value (which could be achieved more easily by
simply passing \code{99}). Default is \code{NULL}.}
\item{level}{(\code{character(1)})\cr
If a (non-missing) level is specified in \code{\link[=parallelStart]{parallelStart()}},
this call is only parallelized if the level specified here matches.
Useful if this function is used in a package.
Default is \code{NA}.}
\item{show.info}{(\code{logical(1)})\cr
Verbose output on console?
Can be used to override setting from options / \code{\link[=parallelStart]{parallelStart()}}.
Default is NA which means no overriding.}
}
\value{
Result.
}
\description{
Uses the parallelization mode and the other options specified in
\code{\link[=parallelStart]{parallelStart()}}.
Libraries and source file can be initialized on slaves with
\code{\link[=parallelLibrary]{parallelLibrary()}} and \code{\link[=parallelSource]{parallelSource()}}.
Large objects can be separately exported via \code{\link[=parallelExport]{parallelExport()}},
they can be simply used under their exported name in slave body code.
Regarding error handling, see the argument \code{impute.error}.
}
\examples{
parallelStart()
parallelMap(identity, 1:2)
parallelStop()
}
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