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imneme / xoshiro256-similarity.c
Created Dec 4, 2020
This code shows self-similarity issues with Vigna's xoshiro256**. The original version of this code was written by Tyge Løvset.
View xoshiro256-similarity.c
/*
* Show self-similarity issues with Vigna's xoshiro256**
*
* Originally posted in a NumPy developers discussion by Tyge Løvset
* but simplified to only mix 32 outputs.
*
* Compile, and then test with PractRand by running
*
* ./xoshiro256-similarity \
* | ./RNG_test stdin64 -te 1 -tlmin 15 -tlmax 50 -tlmaxonly -multithreaded
@imneme
imneme / seeding_bias.cpp
Last active Jun 24, 2019
Seeding Bias Test
View seeding_bias.cpp
/*
* Seeding Bias Test
*
* - Runs through all possible seeds and examines the output for
* bias. Doing so is only practical for 32-bit (or less) seeds
* and 32-bit (or less) output.
*
* Compilation note:
*
* - You need to define the following preprocessor symbols to compile this
@imneme
imneme / chacha.hpp
Last active Nov 19, 2021 — forked from orlp/chacha.h
C++11 ChaCha implementation.
View chacha.hpp
#ifndef CHACHA_HPP_INCLUDED
#define CHACHA_HPP_INCLUDED 1
/*
* A C++ version of ChaCha PRNG (*modified* from Orson Peters original code)
*
* Changes Copyright (c) 2017-18 Melissa E. O'Neill, licence as below.
*
* Changes compared to original 2015 version:
* - Some formatting fixes
@imneme
imneme / arc4.hpp
Created Jul 5, 2018
A C++ port of the OpenBSD Arc4 random number generator
View arc4.hpp
#ifndef ARC4_HPP_INCLUDED
#define ARC4_HPP_INCLUDED 1
/*
* A C++ port of the OpenBSD Arc4 random number generator
*
* The MIT License (MIT)
*
* Copyright (C) 1996 David Mazieres <dm@lcs.mit.edu> for the OpenBSD project
* C++ Port Copyright (c) 2014-18 Melissa E. O'Neill
@imneme
imneme / splitmix.hpp
Created Jul 4, 2018
A C++ implementation of SplitMix
View splitmix.hpp
#ifndef SPLITMIX_HPP_INCLUDED
#define SPLITMIX_HPP_INCLUDED 1
/*
* A C++ implementation of SplitMix
* Original design by Guy L. Steele, Jr., Doug Lea and Christine H. Flood
* Described in _Fast splittable pseudorandom number generators_
* http://dx.doi.org/10.1145/2714064.2660195 and implemented in
* Java 8 as SplittableRandom
* Based on code from the original paper, with revisions based on changes
@imneme
imneme / xoshiro.hpp
Created Jul 4, 2018
A C++ implementation of a family of Xoshiro generators
View xoshiro.hpp
#ifndef XOSHIRO_HPP_INCLUDED
#define XOSHIRO_HPP_INCLUDED 1
/*
* A C++ implementation of a family of Xoshiro generators.
*
* See:
* https://arxiv.org/abs/1805.01407
* http://xoshiro.di.unimi.it/xoshiro256plus.c
* http://xoshiro.di.unimi.it/xoshiro256starstar.c
@imneme
imneme / xoshiro-bad-repeats.c
Created Jun 11, 2018
Xoshiro256** Bad Repeats Demonstration
View xoshiro-bad-repeats.c
/*
* Xoshiro256** Bad Repeats Demonstration
*
* gcc -std=c99 -Wall -o xoshiro-bad-repeats xoshiro-bad-repeats.c
* ./xoshiro-bad-repeats | less
*
* In a PRNG the size of Xoshiro256**, we should expect about 10 "5-in-7"
* repeats. Xoshiro256** has more than 18 billion billion of them, which
* is rather too many. In fact, the number of bad repeats is larger than
* the 2**64 range of the generator!
@imneme
imneme / rng_adapters.hpp
Created Jun 9, 2018
A C++ implementation of a set of PRNG adapters
View rng_adapters.hpp
#ifndef RND_ADAPTERS_HPP_INCLUDED
#define RND_ADAPTERS_HPP_INCLUDED 1
/*
* A C++ implementation of a set of PRNG adapters.
*
* The MIT License (MIT)
*
* Copyright (c) 2018 Melissa E. O'Neill
*
@imneme
imneme / lehmer.hpp
Created Jun 9, 2018
A C++ implementation of 128-bit Lehmer-style PRNGs
View lehmer.hpp
#ifndef LEHMER_HPP_INCLUDED
#define LEHMER_HPP_INCLUDED 1
/*
* A C++ implementation of fast, 128-bit, Lehmer-style PRNGs
*
* The MIT License (MIT)
*
* Copyright (c) 2018 Melissa E. O'Neill
*
@imneme
imneme / sfc.hpp
Last active Sep 6, 2022
A C++ implementation of Chris Doty-Humphrey's SFC PRNG(s)
View sfc.hpp
#ifndef SFC_HPP_INCLUDED
#define SFC_HPP_INCLUDED 1
/*
* A C++ implementation of Chris Doty-Humphrey's SFC PRNG(s)
*
* The MIT License (MIT)
*
* Copyright (c) 2018 Melissa E. O'Neill
*