Options for how futures are partitioned and resolved

Usage

futurize_options(
  seed = FALSE,
  globals = TRUE,
  packages = NULL,
  stdout = TRUE,
  conditions = "condition",
  scheduling = 1,
  chunk_size = NULL,
  ...
)

Arguments

seed: (optional) If TRUE, the random seed, that is, the state of the random number generator (RNG) will be set such that statistically sound random numbers are produced (also during parallelization). If FALSE (default), it is assumed that the future expression neither needs nor uses random number generation. To use a fixed random seed, specify a L'Ecuyer-CMRG seed (seven integers) or a regular RNG seed (a single integer). If the latter, then a L'Ecuyer-CMRG seed will be automatically created based on the given seed. Furthermore, if FALSE, then the future will be monitored to make sure it does not use random numbers. If it does and depending on the value of option future.rng.onMisuse, the check is ignored, an informative warning, or error will be produced. If seed is NULL, then the effect is as with seed = FALSE but without the RNG check being performed.
globals: (optional) a logical, a character vector, or a named list to control how globals are handled. For details, see section 'Globals used by future expressions' in the help for future().
packages: (optional) a character vector specifying packages to be attached in the R environment evaluating the future.
stdout: If TRUE (default), then the standard output is captured, and re-outputted when value() is called. If FALSE, any output is silenced (by sinking it to the null device as it is outputted). Using stdout = structure(TRUE, drop = TRUE) causes the captured standard output to be dropped from the future object as soon as it has been relayed. This can help decrease the overall memory consumed by captured output across futures. Using stdout = NA fully avoids intercepting the standard output; behavior of such unhandled standard output depends on the future backend.
conditions: A character string of condition classes to be captured and relayed. The default is to relay all conditions, including messages and warnings. To drop all conditions, use conditions = character(0). Errors are always relayed. Attribute exclude can be used to ignore specific classes, e.g. conditions = structure("condition", exclude = "message") will capture all condition classes except those that inherit from the message class. Using conditions = structure(..., drop = TRUE) causes any captured conditions to be dropped from the future object as soon as they have been relayed, e.g. by value(f). This can help decrease the overall memory consumed by captured conditions across futures. Using conditions = NULL (not recommended) avoids intercepting conditions, except from errors; behavior of such unhandled conditions depends on the future backend and the environment from which R runs.
scheduling: Average number of futures ("chunks") per worker. If 0.0, then a single future is used to process all elements of X. If 1.0 or TRUE, then one future per worker is used. If 2.0, then each worker will process two futures (if there are enough elements in X). If Inf or FALSE, then one future per element of X is used. Only used if chunk_size is NULL.
chunk_size: The average number of elements per future ("chunk"). If Inf, then all elements are processed in a single future. If NULL, then argument scheduling is used.
...: Additional named options.

Value

A named list of future options. Attribute specified is a character vector of future options that were explicitly specified.

Examples

# Default futurize options
str(futurize_options())
#> List of 7
#>  $ seed      : logi FALSE
#>  $ globals   : logi TRUE
#>  $ packages  : NULL
#>  $ stdout    : logi TRUE
#>  $ conditions: chr "condition"
#>  $ scheduling: num 1
#>  $ chunk_size: NULL
#>  - attr(*, "specified")= chr(0)