mcparallel
(Dummy Non-Parallel) Evaluate an Expression Asynchronously

Description

These functions are provided for compatibility with open-source R. mcparallel immediately evaluates and saves an expression value. mccollect collects the previously-evaluated values.

Usage

mcparallel(expr, name, mc.set.seed = TRUE, silent = FALSE, 
	         mc.affinity = NULL, mc.interactive = FALSE)
mccollect(jobs, wait = TRUE, timeout = 0, intermediate = FALSE)
mcaffinity(affinity = NULL)
mc.reset.stream()

Arguments

expr an expression to evaluate.
name an optional character string giving the job name. If it is given and not NULL, it is set as the "name" component of the return list.
mc.set.seed This argument is ignored by Spotfire Enterprise Runtime for R.
silent This argument is ignored by Spotfire Enterprise Runtime for R.
mc.affinity This argument is ignored by Spotfire Enterprise Runtime for R.
mc.interactive This argument is ignored by Spotfire Enterprise Runtime for R.
jobs a list of job objects returned from mcparallel, specifying the jobs whose results to collect. It can also be a single job object or an integer vector of process IDs extracted from these job objects. If it is missing, then all known jobs are collected.
wait This argument is ignored by Spotfire Enterprise Runtime for R.
timeout This argument is ignored by Spotfire Enterprise Runtime for R.
intermediate This argument is ignored by Spotfire Enterprise Runtime for R.
affinity This argument is ignored by Spotfire Enterprise Runtime for R.

Details

Open-source R implements mcparallel by evaluating expr in parallel on a separate process, using forking on Unix/Linux. mccollect collects the values of these expressions evaluated on these separate processes.
To support existing code, Spotfire Enterprise Runtime for R defines these functions to provide similar (non-parallel) functionality. mcparallel immediately evaluates and saves the value of expr, and mccollect collects the previously-evaluated values.
In open-source R, mcaffinity sets the CPU affinity where the spawned processes should run. In Spotfire Enterprise Runtime for R, this function does nothing.
In open-source R, mc.reset.stream resets the "L'Ecuyer-CMRG" random number generator. In Spotfire Enterprise Runtime for R, this function is defined for compatibility, but it does not reset the random number generators.
Value
mcparallelreturns an object of class "parallelJob", which inherits from classes "childProcess" and "process". A "name" component is added to this object if the name argument is given and not NULL.
mccollectreturns a list of the values evaluated by the specified jobs. The name of each element of the list is the process ID of the job. If the jobs argument is a list of job objects, and they have "name" components, these names are used instead.
mcaffinityreturns the value affinity.
mc.reset.streaminvisibly returns either the seed for the "L'Ecuyer-CMRG" random number generator if it is the current RNG, or it returns NULL.
Differences between Spotfire Enterprise Runtime for R and Open-source R
Spotfire Enterprise Runtime for R defines mcparallel and mccollect for compatibility with open-source R, but these functions don't evaluate expressions in separate processes.
Spotfire Enterprise Runtime for R defines mc.reset.stream for compatibility with open-source R, but this function doesn't reset or affect the random number generators.
See Also
mclapply, pvec, nextRNGStream.
Examples
## Not run: 
x <- mcparallel(runif(10), name = "uniformJob")
y <- mcparallel(rnorm(10))
vals <- mccollect(list(x, y))

## End(Not run)
Package parallel version 6.1.1-7
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