6 /* Copyright (C) 1999,2000,2001, 2006, 2010 Free Software Foundation, Inc.
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 #include "libguile/__scm.h"
29 * A plugin interface for RNGs
31 * Using this interface, it is possible for the application to tell
32 * libguile to use a different RNG. This is desirable if it is
33 * necessary to use the same RNG everywhere in the application in
34 * order to prevent interference, if the application uses RNG
35 * hardware, or if the application has special demands on the RNG.
37 * Look how the default generator is "plugged in" in scm_init_random().
40 typedef struct scm_t_rstate {
43 /* Custom fields follow here */
46 typedef struct scm_t_rng {
47 size_t rstate_size; /* size of random state */
48 /* Though this returns an unsigned long, it's only 32 bits of randomness. */
49 unsigned long (*random_bits) (scm_t_rstate *state); /* gives 32 random bits */
50 void (*init_rstate) (scm_t_rstate *state, const char *seed, int n);
51 scm_t_rstate *(*copy_rstate) (scm_t_rstate *state);
54 SCM_API scm_t_rng scm_the_rng;
60 typedef struct scm_t_i_rstate {
66 /* Though this returns an unsigned long, it's only 32 bits of randomness. */
67 SCM_API unsigned long scm_i_uniform32 (scm_t_i_rstate *);
68 SCM_API void scm_i_init_rstate (scm_t_i_rstate *, const char *seed, int n);
69 SCM_API scm_t_i_rstate *scm_i_copy_rstate (scm_t_i_rstate *);
73 * Random number library functions
75 SCM_API scm_t_rstate *scm_c_make_rstate (const char *, int);
76 SCM_API scm_t_rstate *scm_c_default_rstate (void);
77 #define scm_c_uniform32(RSTATE) scm_the_rng.random_bits (RSTATE)
78 SCM_API double scm_c_uniform01 (scm_t_rstate *);
79 SCM_API double scm_c_normal01 (scm_t_rstate *);
80 SCM_API double scm_c_exp1 (scm_t_rstate *);
81 /* Though this returns an unsigned long, it's only 32 bits of randomness. */
82 SCM_API unsigned long scm_c_random (scm_t_rstate *, unsigned long m);
83 /* This one returns 64 bits of randomness. */
84 SCM_API scm_t_uint64 scm_c_random64 (scm_t_rstate *state, scm_t_uint64 m);
85 SCM_API SCM scm_c_random_bignum (scm_t_rstate *, SCM m);
89 * Scheme level interface
91 SCM_API scm_t_bits scm_tc16_rstate;
92 #define SCM_RSTATEP(obj) SCM_SMOB_PREDICATE (scm_tc16_rstate, obj)
93 #define SCM_RSTATE(obj) ((scm_t_rstate *) SCM_SMOB_DATA (obj))
95 SCM_API unsigned char scm_masktab[256];
97 SCM_API SCM scm_var_random_state;
98 SCM_API SCM scm_random (SCM n, SCM state);
99 SCM_API SCM scm_copy_random_state (SCM state);
100 SCM_API SCM scm_seed_to_random_state (SCM seed);
101 SCM_API SCM scm_random_uniform (SCM state);
102 SCM_API SCM scm_random_solid_sphere_x (SCM v, SCM state);
103 SCM_API SCM scm_random_hollow_sphere_x (SCM v, SCM state);
104 SCM_API SCM scm_random_normal (SCM state);
105 SCM_API SCM scm_random_normal_vector_x (SCM v, SCM state);
106 SCM_API SCM scm_random_exp (SCM state);
107 SCM_API void scm_init_random (void);
109 #endif /* SCM_RANDOM_H */