/* yet another MT19937 c-module for Python: Integer and Real number version Coded by Heiko Stamer , http://gaos.org/~stamer based on the sources of mt19937.c and mt19937int.c by Takuji Nishimura. REQUIREMENTS && BUILD && INSTALL: (REQ) Python >= 1.5, libpython (set the correct LD_LIBRARY_PATH) (1) `gcc -c MT19937module.c` (2) `ld -shared MT19937module.o -o MT19937module.so` (3) Copy MT19937module.o, MT19937module.so to the Python module search path. (4) Check the output of MT19937test.py for module testing. */ /* MT19937.genrandLong() generates a pseudorandom unsigned integer (32bit) which is uniformly distributed among 0 to 2^32-1 for each call. MT19937.genrandFloat() generates a pseudorandom real number (double) which is uniformly distributed on [0,1]-interval for each call. MT19937.sgenrand(seed) set initial values to the working area of 624 words. Before using genrand*() this function has to be called once. (The seed is any 32-bit integer except for zero.) */ /* This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* Copyright (C) 1997 Makoto Matsumoto and Takuji Nishimura. Any feedback is very welcome. For any question, comments, see http://www.math.keio.ac.jp/matumoto/emt.html or email matumoto@math.keio.ac.jp */ /* Period parameters */ #define N 624 #define M 397 #define MATRIX_A 0x9908b0df /* constant vector a */ #define UPPER_MASK 0x80000000 /* most significant w-r bits */ #define LOWER_MASK 0x7fffffff /* least significant r bits */ /* Tempering parameters */ #define TEMPERING_MASK_B 0x9d2c5680 #define TEMPERING_MASK_C 0xefc60000 #define TEMPERING_SHIFT_U(y) (y >> 11) #define TEMPERING_SHIFT_S(y) (y << 7) #define TEMPERING_SHIFT_T(y) (y << 15) #define TEMPERING_SHIFT_L(y) (y >> 18) static unsigned long mt[N]; /* the array for the state vector */ static int mti=N+1; /* mti==N+1 means mt[N] is not initialized */ /* initializing the array with a NONZERO seed */ void sgenrand(seed) unsigned long seed; { /* setting initial seeds to mt[N] using */ /* the generator Line 25 of Table 1 in */ /* [KNUTH 1981, The Art of Computer Programming */ /* Vol. 2 (2nd Ed.), pp102] */ /* same (Line 15 of Table 1) in [KNUTH 1997, The Art of Computer Programming, Vol. 2 (3rd Ed.), pp106] */ mt[0]= seed & 0xffffffff; for (mti=1; mti= N) { /* generate N words at one time */ int kk; if (mti == N+1) /* if sgenrand() has not been called, */ sgenrand(4357); /* a default initial seed is used */ for (kk=0;kk> 1) ^ mag01[y & 0x1]; } for (;kk> 1) ^ mag01[y & 0x1]; } y = (mt[N-1]&UPPER_MASK)|(mt[0]&LOWER_MASK); mt[N-1] = mt[M-1] ^ (y >> 1) ^ mag01[y & 0x1]; mti = 0; } y = mt[mti++]; y ^= TEMPERING_SHIFT_U(y); y ^= TEMPERING_SHIFT_S(y) & TEMPERING_MASK_B; y ^= TEMPERING_SHIFT_T(y) & TEMPERING_MASK_C; y ^= TEMPERING_SHIFT_L(y); return y; } double /* generating reals */ genrandFloat() { unsigned long y; static unsigned long mag01[2]={0x0, MATRIX_A}; /* mag01[x] = x * MATRIX_A for x=0,1 */ if (mti >= N) { /* generate N words at one time */ int kk; if (mti == N+1) /* if sgenrand() has not been called, */ sgenrand(4357); /* a default initial seed is used */ for (kk=0;kk> 1) ^ mag01[y & 0x1]; } for (;kk> 1) ^ mag01[y & 0x1]; } y = (mt[N-1]&UPPER_MASK)|(mt[0]&LOWER_MASK); mt[N-1] = mt[M-1] ^ (y >> 1) ^ mag01[y & 0x1]; mti = 0; } y = mt[mti++]; y ^= TEMPERING_SHIFT_U(y); y ^= TEMPERING_SHIFT_S(y) & TEMPERING_MASK_B; y ^= TEMPERING_SHIFT_T(y) & TEMPERING_MASK_C; y ^= TEMPERING_SHIFT_L(y); return ( (double)y / (unsigned long)0xffffffff ); } /* Here starts the Python part ... */ #include static PyObject * MT19937module_sgenrand(self, args) PyObject *self; PyObject *args; { long int seed; if (!PyArg_ParseTuple(args, "l", &seed)) return NULL; sgenrand(seed); Py_INCREF(Py_None); return Py_None; } static PyObject * MT19937module_genrandLong(self, args) PyObject *self; PyObject *args; { unsigned long value = genrandLong(); return PyLong_FromUnsignedLong(value); } static PyObject * MT19937module_genrandFloat(self, args) PyObject *self; PyObject *args; { double value = genrandFloat(); return PyFloat_FromDouble(value); } static PyMethodDef MT19937Methods[] = { {"sgenrand", MT19937module_sgenrand, METH_VARARGS}, {"genrandLong", MT19937module_genrandLong, METH_VARARGS}, {"genrandFloat", MT19937module_genrandFloat, METH_VARARGS}, {NULL, NULL} }; void initMT19937() { (void) Py_InitModule("MT19937", MT19937Methods); }