Assign cores automatically for parallel processing, while reserving some.
set_cores(workers = 0.9, progressbar = TRUE, verbose = TRUE)Number (>1) or proportion (<1) of worker cores to use.
logical(1) Enable progress bar
(based on plyr:::progress_text).
 Enabling the progress bar changes the default value of tasks to
 .Machine$integer.max, so that progress is reported for
 each element of X.
Print messages.
List of core allocations.