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$DistributedContexts

is the default value of the DistributedContexts option of functions such as ParallelTable and ParallelMap.

Details
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Basic Examples  
Scope  
Properties & Relations  
Possible Issues  
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$DistributedContexts

$DistributedContexts

is the default value of the DistributedContexts option of functions such as ParallelTable and ParallelMap.

Details

  • Before a parallel computation, definitions of symbols to be evaluated in a parallel kernel will automatically be distributed to all kernels, provided these symbols belong to a context given in the DistributedContexts option.
  • The initial value is $DistributedContexts:=$Context, which distributes definitions of all symbols in the current context, but does not distribute definitions of symbols from packages.

Examples

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Basic Examples  (1)

Turn off automatic distribution of functions:

Wolfram Language code: $DistributedContexts = None;
Wolfram Language code: f[i_] := {i, $KernelID}
Wolfram Language code: ParallelMap[f, {1, 2, 3, 4}]

Restore the default value:

Wolfram Language code: $DistributedContexts := $Context

Scope  (5)

By default, definitions in the current context are distributed automatically:

Wolfram Language code: remote[x_] := {$KernelID, x ^ 3}
Wolfram Language code: ParallelTable[remote[i], {i, 4}]

Do not distribute any definitions:

Wolfram Language code: $DistributedContexts = None;
Wolfram Language code: local[x_] := {$KernelID, x ^ 2}
Wolfram Language code: ParallelTable[local[i], {i, 4}]

Distribute definitions for all symbols in all contexts appearing in a parallel computation:

Wolfram Language code: $DistributedContexts = Automatic;
Wolfram Language code: a`k := $KernelID b`k := -$KernelID
Wolfram Language code: ParallelTable[{a`k, b`k}, {4}]

Distribute only definitions in the given contexts:

Wolfram Language code: $DistributedContexts = "a`";
Wolfram Language code: a`m := $KernelID b`m := -$KernelID
Wolfram Language code: ParallelTable[{a`m, b`m}, {4}]

Restore the default value:

Wolfram Language code: $DistributedContexts := $Context

Properties & Relations  (1)

Find all parallel functions that currently use $DistributedContexts:

Wolfram Language code: Select[Names["System`Parallel*"], MemberQ[Options[Symbol[#]], DistributedContexts :> $DistributedContexts]&]

Possible Issues  (1)

The value of $DistributedContexts is not used in Parallelize:

Wolfram Language code: $DistributedContexts = None;
Wolfram Language code: local1[x_] := {$KernelID, x ^ 2}
Wolfram Language code: Parallelize[Table[local1[i], {i, 4}]]

Set the value of the DistributedContexts option of Parallelize:

Wolfram Language code: SetOptions[Parallelize, DistributedContexts -> None]
Wolfram Language code: local2[x_] := {$KernelID, x ^ 3}
Wolfram Language code: Parallelize[Table[local2[i], {i, 4}]]

Restore all settings to their default values:

Wolfram Language code: $DistributedContexts := $Context
Wolfram Language code: SetOptions[Parallelize, DistributedContexts :> $Context]
Wolfram Research (2010), $DistributedContexts, Wolfram Language function, https://reference.wolfram.com/language/ref/$DistributedContexts.html.

Text

Wolfram Research (2010), $DistributedContexts, Wolfram Language function, https://reference.wolfram.com/language/ref/$DistributedContexts.html.

CMS

Wolfram Language. 2010. "$DistributedContexts." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/$DistributedContexts.html.

APA

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

BibTeX

@misc{reference.wolfram_2026_$distributedcontexts, author="Wolfram Research", title="{$DistributedContexts}", year="2010", howpublished="\url{https://reference.wolfram.com/language/ref/$DistributedContexts.html}", note=[Accessed: 13-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_$distributedcontexts, organization={Wolfram Research}, title={$DistributedContexts}, year={2010}, url={https://reference.wolfram.com/language/ref/$DistributedContexts.html}, note=[Accessed: 13-June-2026]}