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Create the qs argument of tar_resources() to specify optional settings for big data storage formats powered by the qs R package. See the format argument of tar_target() for details.

Usage

tar_resources_qs(
  compress_level = targets::tar_option_get("resources")$qs$compress_level,
  shuffle = targets::tar_option_get("resources")$qs$shuffle,
  nthreads = targets::tar_option_get("resources")$qs$nthreads,
  preset = NULL
)

Arguments

compress_level

Positive integer, compress_level argument of qs2::qs_save() to control the compression level.

shuffle

TRUE to use byte shuffling in qs2::qs_save() to improve compression at the cost of some computation time, FALSE to forgo byte shuffling.

nthreads

Positive integer, number of threads to use for functions in the qs2 package to save and read the data.

preset

Deprecated in targets version 1.8.0.9014 (2024-11-11) and not used.

Value

Object of class "tar_resources_qs", to be supplied to the qs argument of tar_resources().

Resources

Functions tar_target() and tar_option_set() each takes an optional resources argument to supply non-default settings of various optional backends for data storage and high-performance computing. The tar_resources() function is a helper to supply those settings in the correct manner.

In targets version 0.12.2 and above, resources are inherited one-by-one in nested fashion from tar_option_get("resources"). For example, suppose you set tar_option_set(resources = tar_resources(aws = my_aws)), where my_aws equals tar_resources_aws(bucket = "x", prefix = "y"). Then, tar_target(data, get_data() will have bucket "x" and prefix "y". In addition, if new_resources equals tar_resources(aws = tar_resources_aws(bucket = "z"))), then tar_target(data, get_data(), resources = new_resources) will use the new bucket "z", but it will still use the prefix "y" supplied through tar_option_set(). (In targets 0.12.1 and below, options like prefix do not carry over from tar_option_set() if you supply non-default resources to tar_target().)

Examples

# Somewhere in you target script file (usually _targets.R):
tar_target(
  name,
  command(),
  format = "qs",
  resources = tar_resources(
    qs = tar_resources_qs(preset = "fast")
  )
)
#> <tar_stem> 
#>   name: name 
#>   description:  
#>   command:
#>     command() 
#>   format: qs 
#>   repository: local 
#>   iteration method: vector 
#>   error mode: stop 
#>   memory mode: persistent 
#>   storage mode: main 
#>   retrieval mode: main 
#>   deployment mode: worker 
#>   priority: 0 
#>   resources:
#>     qs: <environment> 
#>   cue:
#>     seed: TRUE
#>     file: TRUE
#>     iteration: TRUE
#>     repository: TRUE
#>     format: TRUE
#>     depend: TRUE
#>     command: TRUE
#>     mode: thorough 
#>   packages:
#>     targets
#>     stats
#>     graphics
#>     grDevices
#>     utils
#>     datasets
#>     methods
#>     base 
#>   library:
#>     NULL