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PCG Random Number Generation, C++ Edition

This code provides an implementation of the PCG family of random number generators, which are fast, statistically excellent, and offer a number of useful features.

Full details can be found at the PCG-Random website. This version of the code provides many family members -- if you just want one simple generator, you may prefer the minimal C version of the library.

There are two kinds of generator, normal generators and extended generators. Extended generators provide k dimensional equidistribution and can perform party tricks, but generally speaking most people only need the normal generators.

There are two ways to access the generators, using a convenience typedef or by using the underlying templates directly (similar to C++11's std::mt19937 typedef vs its std::mersenne_twister_engine template). For most users, the convenience typedef is what you want, and probably you're fine with pcg32 for 32-bit numbers. If you want 64-bit numbers, either use pcg64 (or, if you're on a 32-bit system, making 64 bits from two calls to pcg32_k2 may be faster).

Documentation and Examples

Visit PCG-Random website for information on how to use this library, or look at the sample code in the sample directory -- hopefully it should be fairly self explanatory.


The code is written in C++11, as an include-only library (i.e., there is nothing you need to build). There are some provided demo programs and tests however. On a Unix-style system (e.g., Linux, Mac OS X) you should be able to just type


To build the demo programs.



make test

Directory Structure

The directories are arranged as follows:

  • include -- contains pcg_random.hpp and supporting include files
  • test-high -- test code for the high-level API where the functions have shorter, less scary-looking names.
  • sample -- sample code, some similar to the code in test-high but more human readable, some other examples too