Modern Math RngSeeded

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RngSeeded

Creates a random generator from a seed, so the same seed repeats the same sequence.

Syntax

RngSeeded( byval seed as uint64 ) as Rng

Notes

• Reproducible: the same seed gives the same sequence on every run and every platform, which is what a test needs.
• RngFromEntropy is the other constructor, seeded from the OS and therefore different every run.
• Not cryptographically secure -- knowing a few outputs reveals the state. CryptoBytes is the one for keys and tokens.

Examples

#import "std/numeric"
using numeric

dim as uint64 seed = 12345
dim a as Rng = RngSeeded( seed )
dim b as Rng = RngSeeded( seed )

'' The same seed gives the same sequence -- which is what makes a test
'' with random input reproducible
dim as int64 lo = 1, hi = 1000000
print a.NextInt( lo, hi ) = b.NextInt( lo, hi )      '' -1 (true)
print a.NextInt( lo, hi ) = b.NextInt( lo, hi )      '' -1 (true)

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Library: Math Library
Category: Math Library
Documented under: Members