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BUILT-IN MATHEMATICA SYMBOL

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BlockRandom

BlockRandom[expr]
evaluates expr with all pseudorandom generators localized, so that uses of SeedRandom, RandomInteger, and related functions within the evaluation of expr do not affect subsequent pseudorandom sequences.

MORE INFORMATION

BlockRandom[expr] in effect saves the states of all pseudorandom generators before evaluating expr, then restores them afterwards.

BlockRandom[expr] always gives the same result as just evaluating expr, though it can affect values obtained for subsequent expressions.

BlockRandom has attribute HoldAll.

Many built-in functions in Mathematica effectively use BlockRandom.

EXAMPLES

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Basic Examples (2)

Use BlockRandom to localize the use of a pseudorandom generator:

Use BlockRandom to prevent one use of a randomized algorithm from affecting others:

Use BlockRandom to localize the use of a pseudorandom generator:

In[1]:=

Out[1]=

Use BlockRandom to prevent one use of a randomized algorithm from affecting others:

In[1]:=

Out[1]=

In[2]:=

Out[2]=

Scope (1)

BlockRandom works with all pseudorandom generators in Mathematica:

Applications (2)

Run a randomized algorithm without affecting other random sequences:

Compute a Monte Carlo approximation to

BlockRandom prevents other random sequences from being affected:

Get the "same" random number at different precisions:

Properties & Relations (1)

BlockRandom effectively does the same as resetting the random seed to its previous value: