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.
Details and Options
- 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[expr,RandomSeeding->seeding] specifies that the random generators should be seeded with the specified seeding before evaluating expr.
- BlockRandom has attribute HoldFirst.
- Many built-in functions in the Wolfram Language effectively use BlockRandom.
Examples
open all close allBasic 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:
Scope (1)
BlockRandom works with all pseudorandom generators in the Wolfram Language:
Options (3)
RandomSeeding (3)
Use a particular random seed to ensure predictable results:
When a generator is used outside BlockRandom, the results without seeding are changed:
Use a RandomGeneratorState object to simultaneously specify the seed and method:
Use Automatic seeding to get different results every time:
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:
Properties & Relations (1)
BlockRandom effectively does the same as resetting the random seed to its previous value:
Text
Wolfram Research (2007), BlockRandom, Wolfram Language function, https://reference.wolfram.com/language/ref/BlockRandom.html (updated 2017).
CMS
Wolfram Language. 2007. "BlockRandom." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2017. https://reference.wolfram.com/language/ref/BlockRandom.html.
APA
Wolfram Language. (2007). BlockRandom. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/BlockRandom.html