mersennejs

Mersennejs.js is an abbreviated javascript port of the mersenne twister PRNG at http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/CODES/mt19937ar.c

Only three of its C functions were translated into javascript:

1. init_genrand(seed) which seeds the mersenne twister with a signed or unsigned 32-bit number.
2. genrand_int32() which generates an unsigned 32-bit random number.
3. genrand_real2() which generates a floating point random number on [0,1).

These functions are exported respectively as seed, rand, and random. rand is only exported for unit testing purposes.

The library also exports a function named randint(N). This function is provided as a convenience and is not in the C code. It generates an unsigned number from 0 to N-1 inclusive, with N passed as the first argument.

Compared to most mersenne ports, this library has no constructor and no methods. All its PRNG functions are provided as named exports. The library maintains only one source of state. So there is no need to worry about the instance object, since there is none.

For example:

import { random, randint, seed } from 'mersennejs';
seed(0)  // seed state vector with a 32-bit integer, can be zero
console.log(random())    // returns floating PRN on [0,1)
console.log(randint(10)) // return integer PRN on [0,10)

After minimization, the uncompressed size of the library is just 639 bytes.

To test the port, run "make test". Gcc, node and js24 must all be installed.

• https://github.com/roseengineering/mersennejs