diff options
| -rw-r--r-- | NEWS | 10 | ||||
| -rwxr-xr-x | doc/ref/api-data.texi | 26 | ||||
| -rw-r--r-- | libguile/random.c | 72 | ||||
| -rw-r--r-- | libguile/random.h | 7 |
4 files changed, 107 insertions, 8 deletions
@@ -8,6 +8,16 @@ Please send Guile bug reports to bug-guile@gnu.org. (During the 1.9 series, we will keep an incremental NEWS for the latest prerelease, and a full NEWS corresponding to 1.8 -> 2.0.) +Changes in 1.9.12 (since the 1.9.11 prerelease): + +** Random generator state has an external form + +Now the random number generator state can be obtained in external +(i.e. `read'/`write'-able) form via the new procedure +`random-state->external'. An externalized state can be reinstantiated by +calling `external->random-state'. + + Changes in 1.9.11 (since the 1.9.10 prerelease): ** Renamed module: (rnrs bytevectors) diff --git a/doc/ref/api-data.texi b/doc/ref/api-data.texi index cc1134396..db593073a 100755 --- a/doc/ref/api-data.texi +++ b/doc/ref/api-data.texi @@ -1511,9 +1511,13 @@ through @var{end} (exclusive) bits of @var{n}. The @subsubsection Random Number Generation Pseudo-random numbers are generated from a random state object, which -can be created with @code{seed->random-state}. The @var{state} -parameter to the various functions below is optional, it defaults to -the state object in the @code{*random-state*} variable. +can be created with @code{seed->random-state} or +@code{external->random-state}. An external representation (i.e. one +which can written with @code{write} and read with @code{read}) of a +random state object can be obtained via +@code{random-state->external}. The @var{state} parameter to the +various functions below is optional, it defaults to the state object +in the @code{*random-state*} variable. @deffn {Scheme Procedure} copy-random-state [state] @deffnx {C Function} scm_copy_random_state (state) @@ -1582,6 +1586,22 @@ Return a uniformly distributed inexact real random number in Return a new random state using @var{seed}. @end deffn +@deffn {Scheme Procedure} external->random-state external +@deffnx {C Function} scm_external_to_random_state (external) +Return a new random state from the external representation +@var{external}, which must have been obtained by +@code{random-state->external}. +@end deffn + +@deffn {Scheme Procedure} random-state->external state +@deffnx {C Function} scm_random_state_to_external (state) +Return an external representation of @var{state}. You cannot make +any assumtions on the structure of the returned object besides that +it will be an acceptable argument to @code{external->random-state} +and that it will be able to be written and read back by the Scheme +reader. +@end deffn + @defvar *random-state* The global random state used by the above functions when the @var{state} parameter is not given. diff --git a/libguile/random.c b/libguile/random.c index 1a9fd59ac..f028272f6 100644 --- a/libguile/random.c +++ b/libguile/random.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1999,2000,2001, 2003, 2005, 2006, 2009 Free Software Foundation, Inc. +/* Copyright (C) 1999,2000,2001, 2003, 2005, 2006, 2009, 2010 Free Software Foundation, Inc. * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public License * as published by the Free Software Foundation; either version 3 of @@ -151,6 +151,35 @@ scm_i_copy_rstate (scm_t_i_rstate *state) return memcpy (new_state, state, scm_the_rng.rstate_size); } +SCM_SYMBOL(scm_i_rstate_tag, "multiply-with-carry"); + +void +scm_i_init_rstate_scm (scm_t_i_rstate *state, SCM value) +#define FUNC_NAME "scm_i_init_rstate_scm" +{ + unsigned long w, c; + long length; + + SCM_VALIDATE_LIST_COPYLEN (SCM_ARG1, value, length); + SCM_ASSERT (length == 3, value, SCM_ARG1, FUNC_NAME); + SCM_ASSERT (scm_is_eq (SCM_CAR (value), scm_i_rstate_tag), + value, SCM_ARG1, FUNC_NAME); + SCM_VALIDATE_ULONG_COPY (SCM_ARG1, SCM_CADR (value), w); + SCM_VALIDATE_ULONG_COPY (SCM_ARG1, SCM_CADDR (value), c); + + state->w = w; + state->c = c; +} +#undef FUNC_NAME + +SCM +scm_i_expose_rstate (scm_t_i_rstate *state) +{ + return scm_list_3 (scm_i_rstate_tag, + scm_from_ulong (state->w), + scm_from_ulong (state->c)); +} + /* * Random number library functions @@ -168,6 +197,17 @@ scm_c_make_rstate (const char *seed, int n) return state; } +scm_t_rstate * +scm_c_make_rstate_scm (SCM external) +{ + scm_t_rstate *state; + + state = scm_gc_malloc_pointerless (scm_the_rng.rstate_size, + "random-state"); + state->reserved0 = 0; + scm_the_rng.init_rstate_scm (state, external); + return state; +} scm_t_rstate * scm_c_default_rstate () @@ -420,6 +460,28 @@ SCM_DEFINE (scm_seed_to_random_state, "seed->random-state", 1, 0, 0, } #undef FUNC_NAME +SCM_DEFINE (scm_external_to_random_state, "external->random-state", 1, 0, 0, + (SCM external), + "Return a new random state using @var{external}.\n" + "\n" + "@var{external} must be an external state representation obtained\n" + "from @code{random-state->external}.") +#define FUNC_NAME s_scm_external_to_random_state +{ + return make_rstate (scm_c_make_rstate_scm (external)); +} +#undef FUNC_NAME + +SCM_DEFINE (scm_random_state_to_external, "random-state->external", 1, 0, 0, + (SCM state), + "Return an external representation of @var{state}.") +#define FUNC_NAME s_scm_random_state_to_external +{ + SCM_VALIDATE_RSTATE (1, state); + return scm_the_rng.expose_rstate (SCM_RSTATE (state)); +} +#undef FUNC_NAME + SCM_DEFINE (scm_random_uniform, "random:uniform", 0, 1, 0, (SCM state), "Return a uniformly distributed inexact real random number in\n" @@ -616,9 +678,11 @@ scm_init_random () scm_t_rng rng = { sizeof (scm_t_i_rstate), - (unsigned long (*)()) scm_i_uniform32, - (void (*)()) scm_i_init_rstate, - (scm_t_rstate *(*)()) scm_i_copy_rstate + (unsigned long (*)()) scm_i_uniform32, + (void (*)()) scm_i_init_rstate, + (scm_t_rstate *(*)()) scm_i_copy_rstate, + (void (*)(scm_t_rstate *, SCM)) scm_i_init_rstate_scm, + (SCM (*)(scm_t_rstate *)) scm_i_expose_rstate }; scm_the_rng = rng; diff --git a/libguile/random.h b/libguile/random.h index 6cf404f8d..402c3f1cb 100644 --- a/libguile/random.h +++ b/libguile/random.h @@ -3,7 +3,7 @@ #ifndef SCM_RANDOM_H #define SCM_RANDOM_H -/* Copyright (C) 1999,2000,2001, 2006, 2008 Free Software Foundation, Inc. +/* Copyright (C) 1999,2000,2001, 2006, 2008, 2010 Free Software Foundation, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public License @@ -49,6 +49,8 @@ typedef struct scm_t_rng { unsigned long (*random_bits) (scm_t_rstate *state); /* gives 32 random bits */ void (*init_rstate) (scm_t_rstate *state, const char *seed, int n); scm_t_rstate *(*copy_rstate) (scm_t_rstate *state); + void (*init_rstate_scm) (scm_t_rstate *state, SCM exposed); + SCM (*expose_rstate) (scm_t_rstate *state); } scm_t_rng; SCM_API scm_t_rng scm_the_rng; @@ -66,12 +68,15 @@ typedef struct scm_t_i_rstate { SCM_INTERNAL unsigned long scm_i_uniform32 (scm_t_i_rstate *); SCM_INTERNAL void scm_i_init_rstate (scm_t_i_rstate *, const char *seed, int n); SCM_INTERNAL scm_t_i_rstate *scm_i_copy_rstate (scm_t_i_rstate *); +SCM_INTERNAL void scm_i_init_rstate_scm (scm_t_i_rstate *state, SCM value); +SCM_INTERNAL SCM scm_i_expose_rstate (scm_t_i_rstate *state); /* * Random number library functions */ SCM_API scm_t_rstate *scm_c_make_rstate (const char *, int); +SCM_API scm_t_rstate *scm_c_make_rstate_scm (SCM external); SCM_API scm_t_rstate *scm_c_default_rstate (void); #define scm_c_uniform32(RSTATE) scm_the_rng.random_bits (RSTATE) SCM_API double scm_c_uniform01 (scm_t_rstate *); |