ell1e / mtwister

A pure C implementation of the Mersenne twister is a pseudo-random number generation algorithm.

The MTwister C Library

The Mersenne twister is a pseudo-random number generation algorithm that was developed in 1997 by Makoto Matsumoto (松本 眞) and Takuji Nishimura (西村 拓 士). Although improvements on the original algorithm have since been made, the original algorithm is still both faster and "more random" than the built-in generators in many common programming languages (C and Java included).

There are already many implementations of the algorithm, so why did I write one myself? There are a number of reasons:

1. the pseudocode on Wikipedia suggested that it was relatively simple to implement;
2. I never trust pseudocode on Wikipedia, so I wanted an implementation from the original academic paper; and
3. it would have been just as easy to implement it myself than to figure out the API of someone else's ugly C code.

Note that this code has not been tested to a sufficient extent to be confidently used for cryptography.

Example

The following code will create a new random generator seeded at 1337 and print out one thousand random doubles between 0 and 1.

#include <stdio.h>
#include "mtwister.h"

int main() {
  MTRand r = seedRand(1337);
  int i;
  for(i=0; i<1000; i++) {
    printf("%f\n", genRand(&r));
  }
  return 0;
}

License

Public domain. Have fun!