crew_class_controller_sequential: Sequential controller class
| crew_class_controller_sequential | R Documentation |
Sequential controller class
Description
R6 class for sequential controllers.
Details
See crew_controller_sequential().
Super class
crew::crew_class_controller -> crew_class_controller_sequential
Methods
Public methods
Inherited methods
crew::crew_class_controller$collect()crew::crew_class_controller$crashes()crew::crew_class_controller$empty()crew::crew_class_controller$initialize()crew::crew_class_controller$map()crew::crew_class_controller$nonempty()crew::crew_class_controller$pids()crew::crew_class_controller$pop()crew::crew_class_controller$promise()crew::crew_class_controller$resolved()crew::crew_class_controller$saturated()crew::crew_class_controller$started()crew::crew_class_controller$summary()crew::crew_class_controller$terminate()crew::crew_class_controller$unpopped()crew::crew_class_controller$unresolved()crew::crew_class_controller$validate()crew::crew_class_controller$walk()
Method start()
Start the controller if it is not already started.
Usage
crew_class_controller_sequential$start(controllers = NULL)
Arguments
controllersNot used. Included to ensure the signature is compatible with the analogous method of controller groups.
Details
For the sequential controller, there is nothing to do except register the client as started.
Returns
NULL (invisibly).
Method launch()
Does nothing for the sequential controller.
Usage
crew_class_controller_sequential$launch(n = 1L, controllers = NULL)
Arguments
nNumber of workers to launch.
controllersNot used. Included to ensure the signature is compatible with the analogous method of controller groups.
Returns
NULL (invisibly).
Method scale()
Does nothing for the sequential controller.
Usage
crew_class_controller_sequential$scale(throttle = TRUE, controllers = NULL)
Arguments
throttleNot applicable to the sequential controller.
controllersNot used. Included to ensure the signature is compatible with the analogous method of controller groups.
Returns
Invisibly returns FALSE.
Method autoscale()
Not applicable to the sequential controller.
Usage
crew_class_controller_sequential$autoscale(controllers = NULL)
Arguments
controllersNot used. Included to ensure the signature is compatible with the analogous method of controller groups.
Returns
NULL (invisibly).
Method descale()
Not applicable to the sequential controller.
Usage
crew_class_controller_sequential$descale(controllers = NULL)
Arguments
controllersNot used. Included to ensure the signature is compatible with the analogous method of controller groups.
Returns
NULL (invisibly).
Method push()
Push a task to the head of the task list.
Usage
crew_class_controller_sequential$push( command, data = list(), globals = list(), substitute = TRUE, seed = NULL, algorithm = NULL, packages = character(0), library = NULL, seconds_timeout = NULL, scale = TRUE, throttle = TRUE, name = NULL, save_command = NULL, controller = NULL )
Arguments
commandLanguage object with R code to run.
dataNamed list of local data objects in the evaluation environment.
globalsNamed list of objects to temporarily assign to the global environment for the task. This list should include any functions you previously defined in the global environment which are required to run tasks. See the
reset_globalsargument ofcrew_controller_local().substituteLogical of length 1, whether to call
base::substitute()on the supplied value of thecommandargument. IfTRUE(default) thencommandis quoted literally as you write it, e.g.push(command = your_function_call()). IfFALSE, thencrewassumescommandis a language object and you are passing its value, e.g.push(command = quote(your_function_call())).substitute = TRUEis appropriate for interactive use, whereassubstitute = FALSEis meant for automated R programs that invokecrewcontrollers.seedInteger of length 1 with the pseudo-random number generator seed to set for the evaluation of the task. Passed to the
seedargument ofset.seed()if notNULL. Ifalgorithmandseedare bothNULLfor the sequential controller, then the random number generator defaults to the current RNG of the local R session where the sequential controller lives.algorithmInteger of length 1 with the pseudo-random number generator algorithm to set for the evaluation of the task. Passed to the
kindargument ofRNGkind()if notNULL. Ifalgorithmandseedare bothNULLfor the sequential controller, then the random number generator defaults to the current RNG of the local R session where the sequential controller lives.packagesCharacter vector of packages to load for the task.
libraryLibrary path to load the packages. See the
lib.locargument ofrequire().seconds_timeoutNot used in the sequential controller..
scaleNot used in the sequential controller.
throttleNot used in the sequential controller.
nameCharacter string, name of the task. If
NULL, then a random name is generated automatically. The name of the task must not conflict with the name of another task pushed to the controller. Any previous task with the same name must first be popped before a new task with that name can be pushed.save_commandDeprecated on 2025-01-22 (
crewversion 0.10.2.9004) and no longer used.controllerNot used. Included to ensure the signature is compatible with the analogous method of controller groups.
Returns
Invisibly returns a mirai-like list where the data
element is the result of the task.
Method wait()
Not applicable to the sequential controller.
Usage
crew_class_controller_sequential$wait( mode = "all", seconds_interval = NULL, seconds_timeout = Inf, scale = TRUE, throttle = TRUE, controllers = NULL )
Arguments
modeNot applicable to the sequential controller.
seconds_intervalNot applicable to the sequential controller.
seconds_timeoutNot applicable to the sequential controller.
scaleNot applicable to the sequential controller.
throttleNot applicable to the sequential controller.
controllersNot used. Included to ensure the signature is compatible with the analogous method of controller groups.
Returns
Always returns TRUE (invisibly)
for the sequential controller.
Method push_backlog()
Not applicable to the sequential controller.
Usage
crew_class_controller_sequential$push_backlog(name, controller = NULL)
Arguments
nameCharacter of length 1 with the task name to push to the backlog.
controllerNot used. Included to ensure the signature is compatible with the analogous method of controller groups.
Returns
NULL (invisibly).
Method pop_backlog()
Not applicable to the sequential controller.
Usage
crew_class_controller_sequential$pop_backlog(controllers = NULL)
Arguments
controllersNot used. Included to ensure the signature is compatible with the analogous method of controller groups.
Returns
Always character(0L) for the sequential controller.
Method cancel()
Not applicable to the sequential controller.
Usage
crew_class_controller_sequential$cancel(names = character(0L), all = FALSE)
Arguments
namesNot applicable to the sequential controller.
allNot applicable to the sequential controller.
See Also
Other sequential controllers:
crew_controller_sequential()
Examples
if (identical(Sys.getenv("CREW_EXAMPLES"), "true")) {
controller <- crew_controller_sequential()
controller$push(name = "task", command = sqrt(4))
controller$pop()
}
