PolyMathOrg / random-numbers

Project to provide different random number generators for the Pharo programming language
MIT License
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Pharo will use PCG as numpy #6

Open Ducasse opened 1 year ago

Ducasse commented 1 year ago

But it can be interesting to package it alone here too.

// *Really* minimal PCG32 code / (c) 2014 M.E. O'Neill / pcg-random.org
// Licensed under Apache License 2.0 (NO WARRANTY, etc. see website)

typedef struct { uint64_t state;  uint64_t inc; } pcg32_random_t;

uint32_t pcg32_random_r(pcg32_random_t* rng)
{
    uint64_t oldstate = rng->state;
    // Advance internal state
    rng->state = oldstate * 6364136223846793005ULL + (rng->inc|1);
    // Calculate output function (XSH RR), uses old state for max ILP
    uint32_t xorshifted = ((oldstate >> 18u) ^ oldstate) >> 27u;
    uint32_t rot = oldstate >> 59u;
    return (xorshifted >> rot) | (xorshifted << ((-rot) & 31));
}
Ducasse commented 1 year ago

https://lemire.me/blog/2017/08/22/testing-non-cryptographic-random-number-generators-my-results/