The following behavior is unexpected for the GB_Flip
RNG. Notice that the verb `roll` produces the same seed
every time instead of updating the seed each time as is
required for most simulation studies, for example those that
employ the random components in batches. Also, in order to
perform a simulation study which synchronizes the random
fractions in order to achieve "variance reduction", an
important strategy, and for other research studies to
replicate exactly the fractions.
The earlier versions of J updated the seed after
each usage. Only with the implementation of the newer RNG's
was this feature changed. I request that the old behavior be
restored at least for GB_Flip.
9!:43]1
9!:0''
16807
roll=: monad define
i=:0
for. i. y do. ? y
i=:>:i
smoutput i,9!:0''
end.
)
roll 10
1 16807
2 16807
3 16807
4 16807
5 16807
6 16807
7 16807
8 16807
9 16807
10 16807
9!:42''
1
--
(B=)
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