1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
|
/* rng/lecuyer21.c
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
/*
* This generator is taken from
*
* Donald E. Knuth
* The Art of Computer Programming
* Volume 2
* Third Edition
* Addison-Wesley
* Page 108
*
* This implementation copyright (C) 2001 Brian Gough, Carlo Perassi
* and (C) 2003 Heiko Bauke.
*/
#include <config.h>
#include <stdlib.h>
#include <gsl/gsl_rng.h>
#define AAA 40692
#define MMM 2147483399UL
#define QQQ 52774
#define RRR 3791
static inline unsigned long int ran_get (void *vstate);
static double ran_get_double (void *vstate);
static void ran_set (void *state, unsigned long int s);
typedef struct
{
unsigned long int x;
}
ran_state_t;
static inline unsigned long int
ran_get (void *vstate)
{
ran_state_t *state = (ran_state_t *) vstate;
long int y = state->x;
long int r = RRR * (y / QQQ);
y = AAA * (y % QQQ) - r;
if (y < 0)
y += MMM;
state->x = y;
return state->x;
}
static double
ran_get_double (void *vstate)
{
ran_state_t *state = (ran_state_t *) vstate;
return ran_get (state) / 2147483399.0;
}
static void
ran_set (void *vstate, unsigned long int s)
{
ran_state_t *state = (ran_state_t *) vstate;
if ((s%MMM) == 0)
s = 1; /* default seed is 1 */
state->x = s % MMM;
return;
}
static const gsl_rng_type ran_type = {
"lecuyer21", /* name */
MMM-1, /* RAND_MAX */
1, /* RAND_MIN */
sizeof (ran_state_t),
&ran_set,
&ran_get,
&ran_get_double
};
const gsl_rng_type *gsl_rng_lecuyer21 = &ran_type;
|
