Modern Math NextDouble

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NextDouble

Returns a random Double from 0 up to but not including 1, with 53 random bits.

Syntax

NextDouble( ) as float64

Notes

• Half-open: 0 is possible, 1 is not. That is what makes lo + NextDouble( ) * ( hi - lo ) never produce hi.
• 53 bits of randomness -- the full significand, not a scaled integer with gaps in it.
• NextDoubleRange is the version that takes bounds.

Examples

#import "std/numeric"
using numeric

dim r as Rng = RngFromEntropy( )

dim as float64 v = r.NextDouble( )
print v >= 0.0 andalso v < 1.0                '' -1 (true)

'' Half-open, so scaling never reaches the upper bound
dim as int32 hits = 0
for i as int32 = 1 to 1000
    if r.NextDouble( ) >= 1.0 then hits += 1
next
print hits                   '' 0

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