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CreateScheduledTask[expr]

creates a local scheduled task that will repeatedly evaluate expr once per second.

CreateScheduledTask[expr,time]

creates a task that will repeatedly evaluate expr every time seconds.

CreateScheduledTask[expr,{time}]

creates a task that will evaluate expr once after time seconds.

CreateScheduledTask[expr,{time,count}]

creates a task that will try evaluating expr once every time seconds up to count times total.

CreateScheduledTask[expr,timespec,start]

creates a task that will evaluate expr according to timespec starting at start time.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
See Also
Tech Notes
History
Cite this Page

CreateScheduledTask

CreateScheduledTask is being phased out in favor of SessionSubmit, which was introduced experimentally in Version 11.2.

CreateScheduledTask[expr]

creates a local scheduled task that will repeatedly evaluate expr once per second.

CreateScheduledTask[expr,time]

creates a task that will repeatedly evaluate expr every time seconds.

CreateScheduledTask[expr,{time}]

creates a task that will evaluate expr once after time seconds.

CreateScheduledTask[expr,{time,count}]

creates a task that will try evaluating expr once every time seconds up to count times total.

CreateScheduledTask[expr,timespec,start]

creates a task that will evaluate expr according to timespec starting at start time.

Details and Options

  • CreateScheduledTask returns a ScheduledTaskObject expression representing the created task.
  • CreateScheduledTask creates a task, but does not start it. The task can be started using StartScheduledTask.
  • CreateScheduledTask creates a task to be run locally in the current Wolfram Language session. No task state is preserved between sessions.
  • The start is taken to be the absolute time when the task is activated.
  • The first evaluation of expr will occur time seconds after it is activated.
  • If two tasks are scheduled to evaluate at the same time, the one added later will execute first.
  • Scheduled tasks do not require a notebook front end to work.
  • By default, if the time necessary to evaluate expr is larger than time, the next pending evaluation is skipped.

Examples

Basic Examples  (6)

Create a task:

Wolfram Language code: t = CreateScheduledTask[Print[DateString[]]]

Start the task:

Wolfram Language code: StartScheduledTask[t]

Stop and remove it:

Wolfram Language code: RemoveScheduledTask[t]

Create a task, which will evaluate x every second:

Wolfram Language code: t = CreateScheduledTask[x]

Assign value to x:

Wolfram Language code: x := Print[DateString[]];

Start the task:

Wolfram Language code: StartScheduledTask[t]
Wolfram Language code: RemoveScheduledTask[t]

Create a task that will be activated 5 seconds from the current time and will print 1 second later:

Wolfram Language code: RunScheduledTask[MessageDialog["text"], {1}, AbsoluteTime[] + 5]

Specify a date to activate the task:

Wolfram Language code: RunScheduledTask[MessageDialog["text"], {1}, AbsoluteTime[{2010, 3, 12, 15, 16, 0}]]

Non-synchronized tasks:

Wolfram Language code: i = 0; RunScheduledTask[++i, 1]; RunScheduledTask[i = 0, 4]; Dynamic[i]

Better synchronization:

Wolfram Language code: j = 0; StartScheduledTask[{CreateScheduledTask[++j, 1], CreateScheduledTask[j = 0, 4]}]; Dynamic[j]
Wolfram Language code: RemoveScheduledTask[ScheduledTasks[]];

Synchronize tasks using an auxiliary task:

Wolfram Language code: n = 1;Dynamic[FlipView[{Graphics[{Red, Disk[]}], Graphics[{Green, Disk[]}]}, n]]
Wolfram Language code: x1 = CreateScheduledTask[StartScheduledTask[{x3}];RemoveScheduledTask[$ScheduledTask], {0.3}]; x2 = CreateScheduledTask[n = 1, 1]; x3 = CreateScheduledTask[n = 2, 1];
Wolfram Language code: ScheduledTasks[]
Wolfram Language code: StartScheduledTask[{x1, x2}];

The auxiliary task x1 was removed:

Wolfram Language code: ScheduledTasks[]

Stop tasks:

Wolfram Language code: StopScheduledTask[ScheduledTasks[]];

Remove all tasks:

Wolfram Language code: RemoveScheduledTask[ScheduledTasks[]];
Wolfram Research (2010), CreateScheduledTask, Wolfram Language function, https://reference.wolfram.com/language/ref/CreateScheduledTask.html (updated 2014).

Text

Wolfram Research (2010), CreateScheduledTask, Wolfram Language function, https://reference.wolfram.com/language/ref/CreateScheduledTask.html (updated 2014).

CMS

Wolfram Language. 2010. "CreateScheduledTask." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2014. https://reference.wolfram.com/language/ref/CreateScheduledTask.html.

APA

Wolfram Language. (2010). CreateScheduledTask. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/CreateScheduledTask.html

BibTeX

@misc{reference.wolfram_2026_createscheduledtask, author="Wolfram Research", title="{CreateScheduledTask}", year="2014", howpublished="\url{https://reference.wolfram.com/language/ref/CreateScheduledTask.html}", note=[Accessed: 15-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_createscheduledtask, organization={Wolfram Research}, title={CreateScheduledTask}, year={2014}, url={https://reference.wolfram.com/language/ref/CreateScheduledTask.html}, note=[Accessed: 15-June-2026]}