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ContinuousTask[expr]

represents a task in which expr is continuously reevaluated.

ContinuousTask[expr,end]

represents a task in which expr is continuously reevaluated until the time specified by end.

ContinuousTask[expr,tspan]

represents a task in which expr is continuously reevaluated over the time span tspan.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
Scope  
Options  
NotificationFunction  
RestartInterval  
TimeZone  
Possible Issues  
Neat Examples  
See Also
Related Guides
History
Cite this Page

ContinuousTask

ContinuousTask[expr]

represents a task in which expr is continuously reevaluated.

ContinuousTask[expr,end]

represents a task in which expr is continuously reevaluated until the time specified by end.

ContinuousTask[expr,tspan]

represents a task in which expr is continuously reevaluated over the time span tspan.

Details and Options

  • CloudSubmit[ContinuousTask[expr]] submits expr for continuous reevaluation in the cloud, starting immediately.
  • Unless they contain blocking functions or Pause specifications, continuous tasks will typically make use of all available processor resources.
  • ContinuousTask is intended primarily for private cloud installations, not the public Wolfram Cloud.
  • If the evaluation of expr leads to abnormal termination or yields $Failed or a Failure object, a series of restarts will be attempted after progressively longer time intervals.
  • Continuous tasks can be controlled using functions like TaskSuspend and TaskResume.
  • The following options can be given:
  • NotificationFunction Automatichow to provide notifications
    RestartInterval Automatichow long to wait before restarting after failure
    TimeZone Automatictime zone for time specifications
  • In ContinuousTask[expr,end], end can be a DateObject or any other date and time specifier.
  • In ContinuousTask[expr,tspan], tspan can be any Quantity object representing a time span.

Examples

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Basic Examples  (1)

In an appropriately configured private cloud, deploy a continuous task:

Wolfram Language code: task = CloudDeploy[ContinuousTask[PutAppend[Now, CloudObject["dates"]]]]

Monitor the task output by reading from the object it is appending to:

Wolfram Language code: ReadList[CloudObject["dates"]]
Wolfram Language code: {DateObject[{2026, 2, 13, 17, 4, 40.5993694}, "Instant", "Gregorian", -6.], DateObject[{2026, 2, 13, 17, 5, 50.8701565}, "Instant", "Gregorian", -6.], DateObject[{2026, 2, 13, 17, 5, 56.3398975}, "Instant", "Gregorian", -6.]}Import["C:\\Users\\jfklein\\Downloads\\ExportMarkdown.wlt"]

Delete the task:

Wolfram Language code: TaskRemove[task]

Scope  (2)

Deploy a continuous task with an end date:

Wolfram Language code: task = CloudDeploy[ContinuousTask[PutAppend[Now, CloudObject["dates"]], Tomorrow]]

Delete the task:

Wolfram Language code: TaskRemove[task]

Deploy a continuous task that runs for 72 hours:

Wolfram Language code: task = CloudDeploy[ContinuousTask[PutAppend[Now, CloudObject["dates"]], Quantity[72, "Hours"]]]

Delete the task:

Wolfram Language code: TaskRemove[task]

Options  (3)

NotificationFunction  (1)

Deploy a continuous task, requesting notifications for all discrete runs:

Wolfram Language code: o = CloudDeploy[ContinuousTask[Pause[10];Now, NotificationFunction -> All]]

Delete the task:

Wolfram Language code: TaskRemove[o]

RestartInterval  (1)

Deploy a continuous task that pauses 5 minutes after a failure:

Wolfram Language code: task = CloudDeploy[ContinuousTask[PutAppend[Now, CloudObject["dates"]], RestartInterval -> Quantity[5, "Minutes"]]]

TimeZone  (1)

Deploy a task that uses $TimeZone set to GMT+2:

Wolfram Language code: task = CloudDeploy[ContinuousTask[CloudPut[{$TimeZone, $TimeZoneEntity, Now, DateString[]}, "result"], None, TimeZone -> 2]]

After waiting a few moments for it run, read from the result object that it wrote, noting the time zone setting was applied:

Wolfram Language code: CloudGet["result"]

Remove the task:

Wolfram Language code: DeleteObject[task]

Possible Issues  (1)

When ContinuousTask is evaluated in the cloud, it has restrictions on memory usage and evaluation time. The limitations are determined by your cloud plan, and the amounts can be found in CloudAccountData as "ScheduledTaskMemoryLimit" and "ScheduledTaskEvaluationTimeLimit":

Wolfram Language code: CloudAccountData /@ {"ScheduledTaskMemoryLimit", "ScheduledTaskEvaluationTimeLimit"}

Neat Examples  (1)

Prepare a cloud object containing a counter:

Wolfram Language code: counterObj = CloudPut[0];

Update the counter from a continuous task:

Wolfram Language code: o = With[{c = counterObj}, CloudDeploy[ContinuousTask[ Pause[5];i = CloudGet[c];CloudPut[i + 1, c] ]] ]

Verify the counter has been updated:

Wolfram Language code: CloudGet[counterObj]

Pause the task:

Wolfram Language code: TaskSuspend[o]

The counter is no longer updating:

Wolfram Language code: CloudGet[counterObj]

Delete the counter and task:

Wolfram Language code: DeleteObject[counterObj]; TaskRemove[o]
Wolfram Research (2015), ContinuousTask, Wolfram Language function, https://reference.wolfram.com/language/ref/ContinuousTask.html (updated 2017).

Text

Wolfram Research (2015), ContinuousTask, Wolfram Language function, https://reference.wolfram.com/language/ref/ContinuousTask.html (updated 2017).

CMS

Wolfram Language. 2015. "ContinuousTask." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2017. https://reference.wolfram.com/language/ref/ContinuousTask.html.

APA

Wolfram Language. (2015). ContinuousTask. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ContinuousTask.html

BibTeX

@misc{reference.wolfram_2026_continuoustask, author="Wolfram Research", title="{ContinuousTask}", year="2017", howpublished="\url{https://reference.wolfram.com/language/ref/ContinuousTask.html}", note=[Accessed: 12-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_continuoustask, organization={Wolfram Research}, title={ContinuousTask}, year={2017}, url={https://reference.wolfram.com/language/ref/ContinuousTask.html}, note=[Accessed: 12-June-2026]}