Random123/gsl_microrng.h
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00001 /* 00002 Copyright 2010-2011, D. E. Shaw Research. 00003 All rights reserved. 00004 00005 Redistribution and use in source and binary forms, with or without 00006 modification, are permitted provided that the following conditions are 00007 met: 00008 00009 * Redistributions of source code must retain the above copyright 00010 notice, this list of conditions, and the following disclaimer. 00011 00012 * Redistributions in binary form must reproduce the above copyright 00013 notice, this list of conditions, and the following disclaimer in the 00014 documentation and/or other materials provided with the distribution. 00015 00016 * Neither the name of D. E. Shaw Research nor the names of its 00017 contributors may be used to endorse or promote products derived from 00018 this software without specific prior written permission. 00019 00020 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 00021 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 00022 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 00023 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 00024 OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 00025 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 00026 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 00027 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 00028 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 00029 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 00030 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 00031 */ 00032 #ifndef __r123_gslmicrorng_dot_h__ 00033 #define __r123_gslmicrorng_dot_h__ 00034 00035 00036 #include <gsl/gsl_rng.h> 00037 #include <string.h> 00038 00079 #define GSL_MICRORNG(NAME, CBRNGNAME, BITS) \ 00080 const gsl_rng_type *gsl_rng_##NAME; \ 00081 \ 00082 typedef struct{ \ 00083 CBRNGNAME##_ctr_t ctr; \ 00084 CBRNGNAME##_ctr_t r; \ 00085 CBRNGNAME##_key_t key; \ 00086 R123_ULONG_LONG n; \ 00087 int elem; \ 00088 } NAME##_state; \ 00089 \ 00090 static unsigned long int NAME##_get(void *vstate){ \ 00091 NAME##_state *st = (NAME##_state *)vstate; \ 00092 const int N=sizeof(st->ctr.v)/sizeof(st->ctr.v[0]); \ 00093 if( st->elem == 0 ){ \ 00094 CBRNGNAME##_ctr_t c = st->ctr; \ 00095 if( st->n >= (1U<<BITS) ) \ 00096 abort(); \ 00097 c.v[N-1] |= st->n<<(R123_W(CBRNGNAME##_ctr_t)-BITS); \ 00098 st->n++; \ 00099 st->r = CBRNGNAME(c, st->key); \ 00100 st->elem = N; \ 00101 } \ 00102 return st->r.v[--st->elem]; \ 00103 } \ 00104 \ 00105 static double NAME##_get_double (void * vstate); \ 00106 \ 00107 static void NAME##_set(void *vstate, unsigned long int s){ \ 00108 NAME##_state *st = (NAME##_state *)vstate; \ 00109 st->elem = 0; \ 00110 st->n = ~0; /* will abort if _reset is not called */ \ 00111 } \ 00112 \ 00113 static const gsl_rng_type NAME##_type = { \ 00114 #NAME, \ 00115 ~0UL>>((R123_W(CBRNGNAME##_ctr_t)>=8*sizeof(unsigned long))? 0 : (8*sizeof(unsigned long) - R123_W(CBRNGNAME##_ctr_t))), \ 00116 0, \ 00117 sizeof(NAME##_state), \ 00118 &NAME##_set, \ 00119 &NAME##_get, \ 00120 &NAME##_get_double \ 00121 }; \ 00122 \ 00123 static double \ 00124 NAME##_get_double (void * vstate) \ 00125 { \ 00126 return NAME##_get (vstate)/(double)NAME##_type.max; \ 00127 } \ 00128 \ 00129 R123_STATIC_INLINE void NAME##_reset(const gsl_rng* gr, CBRNGNAME##_ctr_t c, CBRNGNAME##_key_t k) { \ 00130 NAME##_state* state = (NAME##_state *)gr->state; \ 00131 state->ctr = c; \ 00132 state->key = k; \ 00133 state->n = 0; \ 00134 state->elem = 0; \ 00135 } \ 00136 \ 00137 const gsl_rng_type *gsl_rng_##NAME = &NAME##_type 00138 00139 #endif
