Random123
gsl_microrng.h
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1/*
2Copyright 2010-2011, D. E. Shaw Research.
3All rights reserved.
4
5Redistribution and use in source and binary forms, with or without
6modification, are permitted provided that the following conditions are
7met:
8
9* Redistributions of source code must retain the above copyright
10 notice, this list of conditions, and the following disclaimer.
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12* Redistributions in binary form must reproduce the above copyright
13 notice, this list of conditions, and the following disclaimer in the
14 documentation and/or other materials provided with the distribution.
15
16* Neither the name of D. E. Shaw Research nor the names of its
17 contributors may be used to endorse or promote products derived from
18 this software without specific prior written permission.
19
20THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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30OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31*/
32#ifndef __r123_gslmicrorng_dot_h__
33#define __r123_gslmicrorng_dot_h__
34
35
36#include <gsl/gsl_rng.h>
37#include <string.h>
38
79#define GSL_MICRORNG(NAME, CBRNGNAME) \
80const gsl_rng_type *gsl_rng_##NAME; \
81 \
82typedef struct{ \
83 CBRNGNAME##_ctr_t ctr; \
84 CBRNGNAME##_ctr_t r; \
85 CBRNGNAME##_key_t key; \
86 R123_ULONG_LONG n; \
87 int elem; \
88} NAME##_state; \
89 \
90static unsigned long int NAME##_get(void *vstate){ \
91 NAME##_state *st = (NAME##_state *)vstate; \
92 const int N=sizeof(st->ctr.v)/sizeof(st->ctr.v[0]); \
93 if( st->elem == 0 ){ \
94 CBRNGNAME##_ctr_t c = st->ctr; \
95 c.v[N-1] |= st->n<<(R123_W(CBRNGNAME##_ctr_t)-32); \
96 st->n++; \
97 st->r = CBRNGNAME(c, st->key); \
98 st->elem = N; \
99 } \
100 return 0xffffffff & st->r.v[--st->elem]; \
101} \
102 \
103static double \
104NAME##_get_double (void * vstate) \
105{ \
106 return NAME##_get (vstate)/4294967296.; \
107} \
108 \
109static void NAME##_set(void *vstate, unsigned long int s){ \
110 NAME##_state *st = (NAME##_state *)vstate; \
111 (void)s; /* ignored */ \
112 st->elem = 0; \
113 st->n = ~0; /* will abort if _reset is not called */ \
114} \
115 \
116static const gsl_rng_type NAME##_type = { \
117 #NAME, \
118 0xffffffffUL, \
119 0, \
120 sizeof(NAME##_state), \
121 &NAME##_set, \
122 &NAME##_get, \
123 &NAME##_get_double \
124}; \
125 \
126R123_STATIC_INLINE void NAME##_reset(const gsl_rng* gr, CBRNGNAME##_ctr_t c, CBRNGNAME##_key_t k) { \
127 NAME##_state* state = (NAME##_state *)gr->state; \
128 state->ctr = c; \
129 state->key = k; \
130 state->n = 0; \
131 state->elem = 0; \
132} \
133 \
134const gsl_rng_type *gsl_rng_##NAME = &NAME##_type
135
136#endif