I wanted to ask about the output distribution of floating-point rand(): Naively, I would have expected the following distribution: -the sign bit is zero -the mantissa is a random bitstring -the signigicant is an exponentially distributed integer, e.g. const-leading_zeros of an infinite bitstream …

So it took me a bit to grok what all is going on here. This getfloat_trail function transforms a random UInt32 to a Float32. This is different from our current rand(::Float32) — which is approximated here by getfloat_std — in the following ways: Its output is in (0,1) instead of [0,1). 32 bits i…

Output distribution of rand()

Internals & Design

mbauman Closed October 19, 2023, 1:22pm 9

Closing to focus discussion in Output distribution of rand(), thread 2

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Output distribution of rand()

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