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53 lines
2.0 KiB
Markdown
53 lines
2.0 KiB
Markdown
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# PCG Random Number Generation, C++ Edition
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[PCG-Random website]: http://www.pcg-random.org
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This code provides an implementation of the PCG family of random number
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generators, which are fast, statistically excellent, and offer a number of
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useful features.
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Full details can be found at the [PCG-Random website]. This version
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of the code provides many family members -- if you just want one
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simple generator, you may prefer the minimal C version of the library.
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There are two kinds of generator, normal generators and extended generators.
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Extended generators provide *k* dimensional equidistribution and can perform
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party tricks, but generally speaking most people only need the normal
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generators.
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There are two ways to access the generators, using a convenience typedef
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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).
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## Documentation and Examples
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Visit [PCG-Random website] for information on how to use this library, or look
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at the sample code in the `sample` directory -- hopefully it should be fairly
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self explanatory.
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## Building
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The code is written in C++11, as an include-only library (i.e., there is
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nothing you need to build). There are some provided demo programs and tests
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however. On a Unix-style system (e.g., Linux, Mac OS X) you should be able
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to just type
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make
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To build the demo programs.
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## Testing
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Run
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make test
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## Directory Structure
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The directories are arranged as follows:
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* `include` -- contains `pcg_random.hpp` and supporting include files
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* `test-high` -- test code for the high-level API where the functions have
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shorter, less scary-looking names.
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* `sample` -- sample code, some similar to the code in `test-high` but more
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human readable, some other examples too
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