/* A C-program for TT800 : July 8th 1996 Version */ /* by M. Matsumoto, email: matumoto@math.keio.ac.jp */ /* genrand() generate one pseudorandom number with double precision */ /* which is uniformly distributed on [0,1]-interval */ /* for each call. One may choose any initial 25 seeds */ /* except all zeros. */ /* See: ACM Transactions on Modelling and Computer Simulation, */ /* Vol. 4, No. 3, 1994, pages 254-266. */ #include #define N 25 #define M 7 double genrand() { unsigned long y; static int k = 0; static unsigned long x[N]={ /* initial 25 seeds, change as you wish */ 0x95f24dab, 0x0b685215, 0xe76ccae7, 0xaf3ec239, 0x715fad23, 0x24a590ad, 0x69e4b5ef, 0xbf456141, 0x96bc1b7b, 0xa7bdf825, 0xc1de75b7, 0x8858a9c9, 0x2da87693, 0xb657f9dd, 0xffdc8a9f, 0x8121da71, 0x8b823ecb, 0x885d05f5, 0x4e20cd47, 0x5a9ad5d9, 0x512c0c03, 0xea857ccd, 0x4cc1d30f, 0x8891a8a1, 0xa6b7aadb }; static unsigned long mag01[2]={ 0x0, 0x8ebfd028 /* this is magic vector `a', don't change */ }; if (k==N) { /* generate N words at one time */ int kk; for (kk=0;kk> 1) ^ mag01[x[kk] % 2]; } for (; kk> 1) ^ mag01[x[kk] % 2]; } k=0; } y = x[k]; y ^= (y << 7) & 0x2b5b2500; /* s and b, magic vectors */ y ^= (y << 15) & 0xdb8b0000; /* t and c, magic vectors */ y &= 0xffffffff; /* you may delete this line if word size = 32 */ /* the following line was added by Makoto Matsumoto in the 1996 version to improve lower bit's corellation. Delete this line to o use the code published in 1994. */ y ^= (y >> 16); /* added to the 1994 version */ k++; return( (double) y / (unsigned long) 0xffffffff); } /* this main() output first 50 generated numbers */ main() { int j; for (j=0; j<50; j++) { printf("%5f ", genrand()); if (j%8==7) printf("\n"); } printf("\n"); }