faster rand(::Tuple) #32208
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faster rand(::Tuple) #32208
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rfourquet
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performance
This was an oversight. This makes rand(::MersenneTwister, ::Tuple) generally faster.
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According to recent documentation, it's fine to change generated streams of random numbers for a given seed. Removing |
rfourquet
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StefanKarpinski
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kind:minor change
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No, this is precisely what the "minor change" label is for: changes that are allowed in minor releases but not in patch releases. We do not promise random stream stability but we will not change the behavior of programs in point releases except to fix bugs. |
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I've added the "needs news" label because minor changes should always be mentioned in NEWS. |
rfourquet
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Oops, sorry, I misunderstood! News added at #33404. |
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The idea is quite simple:
L, we do like for length 4, i.e. use a mask:rand(UInt32) & (L-1)rand(Base.OneTo(n))(used inrand(::Tuple)) slower thanrand(1:n)forMersenneTwister.This breaks the reproducibility of generated streams, but we now have a precedent for that.