Evolution of Random Number Generators

Recently noted that mt19937, mt19937_64 are much faster than the standard c++ random generator. They are also possibly better with regards to number distribution, but the performance difference is gigantic on clang. The standard 32 bit std::default_random_generator is almost 40x slower than the 64 bit mt19937_64 one across the board, from -o1 to -O3 march... etc.<p>As all of them are also faster than old school rand, its worth upgrading for the performance increase if nothing else.

I&#x27;m reminded of Chris Wellon&#x27;s &quot;Prospecting for Hash Functions&quot;, where he randomly generates hash functions and then runs them through a couple of tests.<p><a href="https:&#x2F;&#x2F;nullprogram.com&#x2F;blog&#x2F;2018&#x2F;07&#x2F;31&#x2F;" rel="nofollow">https:&#x2F;&#x2F;nullprogram.com&#x2F;blog&#x2F;2018&#x2F;07&#x2F;31&#x2F;</a><p>Out of curiosity, is running the state through a hash a reasonable rand strategy?

The PCG author (Melissa O&#x27;Neill of Harvey Mudd) has an interesting story of how PCG and its paper came about <a href="https:&#x2F;&#x2F;www.pcg-random.org&#x2F;posts&#x2F;history-of-the-pcg-paper.html" rel="nofollow">https:&#x2F;&#x2F;www.pcg-random.org&#x2F;posts&#x2F;history-of-the-pcg-paper.ht...</a> Good to read in case you think that academic peer review is the only way to introduce new and useful methods to the world.

I am looking for a simple random number generator that fills a given amount of slots.<p>Say it is initialized with &quot;size=5&quot; then it might output:<p>3,5,2,1,4<p>Is there something like this?<p>It does not need much statistical resemblence to randomness. Just look kind of random to the eye. And the code should be short. A few lines of Javascript or so.<p>Maybe one approach might be to just loop through the sequence (1,2,3,4,5) and xor the number with some other number? Maybe with 0101010...?