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$RandomGeneratorState

gives a representation of the internal state of the default pseudorandom generator.

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$RandomGeneratorState

$RandomGeneratorState

gives a representation of the internal state of the default pseudorandom generator.

Details

Examples

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Basic Examples  (1)

Get the current state of the pseudorandom generator:

Wolfram Language code: $RandomGeneratorState

Applications  (1)

Create a version of BlockRandom that refuses to run if the current random state cannot be restored:

Wolfram Language code: SetAttributes[myBlockRandom, HoldFirst]; myBlockRandom[args__] := If[$RandomGeneratorState["StateHash"] =!= None, BlockRandom[args], "Aborting as the active method has no restorable state."]

Activate a randomness generation method with no restorable state:

Wolfram Language code: SeedRandom["Method" -> "OpenSSL"]

Because this method cannot be seeded, BlockRandom cannot give reproducible results:

Wolfram Language code: SeedRandom[1234, "Method" -> "OpenSSL"]

The function will refuse to evaluate:

Wolfram Language code: myBlockRandom[RandomReal[]]

Activate a randomness generation method that possesses a restorable state:

Wolfram Language code: SeedRandom["Method" -> "ExtendedCA"]

The function restores the random state at the end of each evaluation:

Wolfram Language code: myBlockRandom[RandomReal[]]

Hence the following result matches the previous result:

Wolfram Language code: myBlockRandom[RandomReal[]]

Properties & Relations  (4)

$RandomGeneratorState returns a RandomGeneratorState object:

Wolfram Language code: $RandomGeneratorState//Head

Using RandomInteger, RandomReal and related functions changes $RandomGeneratorState:

Wolfram Language code: $RandomGeneratorState

Use RandomComplex:

Wolfram Language code: RandomComplex[]

The state has changed as indicated by the new hash:

Wolfram Language code: $RandomGeneratorState

The value of $RandomGeneratorState can be restored with SeedRandom:

Wolfram Language code: state = $RandomGeneratorState; RandomInteger[100, 10]
Wolfram Language code: SeedRandom[state]; RandomInteger[100, 10]

Restoring $RandomGeneratorState after a computation is effectively the same as BlockRandom:

Wolfram Language code: Table[Block[{state, result}, state = $RandomGeneratorState;result = RandomInteger[100];SeedRandom[state];result], {5}]
Wolfram Language code: Table[BlockRandom[RandomInteger[100]], {5}]
Wolfram Research (2020), $RandomGeneratorState, Wolfram Language function, https://reference.wolfram.com/language/ref/$RandomGeneratorState.html.

Text

Wolfram Research (2020), $RandomGeneratorState, Wolfram Language function, https://reference.wolfram.com/language/ref/$RandomGeneratorState.html.

CMS

Wolfram Language. 2020. "$RandomGeneratorState." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/$RandomGeneratorState.html.

APA

Wolfram Language. (2020). $RandomGeneratorState. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/$RandomGeneratorState.html

BibTeX

@misc{reference.wolfram_2026_$randomgeneratorstate, author="Wolfram Research", title="{$RandomGeneratorState}", year="2020", howpublished="\url{https://reference.wolfram.com/language/ref/$RandomGeneratorState.html}", note=[Accessed: 13-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_$randomgeneratorstate, organization={Wolfram Research}, title={$RandomGeneratorState}, year={2020}, url={https://reference.wolfram.com/language/ref/$RandomGeneratorState.html}, note=[Accessed: 13-June-2026]}