extmod/modurandom: Add some extra random functions.

Functions added are:
- randint
- randrange
- choice
- random
- uniform

They are enabled with configuration variable
MICROPY_PY_URANDOM_EXTRA_FUNCS, which is disabled by default.  It is
enabled for unix coverage build and stmhal.
This commit is contained in:
Damien George 2016-01-22 16:19:32 +00:00
parent f5c42dd9d1
commit a53af6c875
5 changed files with 144 additions and 1 deletions

View File

@ -53,6 +53,24 @@ STATIC uint32_t yasmarang(void)
// End of Yasmarang
#if MICROPY_PY_URANDOM_EXTRA_FUNCS
// returns an unsigned integer below the given argument
// n must not be zero
STATIC uint32_t yasmarang_randbelow(uint32_t n) {
uint32_t mask = 1;
while ((n & mask) < n) {
mask = (mask << 1) | 1;
}
uint32_t r;
do {
r = yasmarang() & mask;
} while (r >= n);
return r;
}
#endif
STATIC mp_obj_t mod_urandom_getrandbits(mp_obj_t num_in) {
int n = mp_obj_get_int(num_in);
if (n > 32 || n == 0) {
@ -75,10 +93,122 @@ STATIC mp_obj_t mod_urandom_seed(mp_obj_t seed_in) {
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_urandom_seed_obj, mod_urandom_seed);
#if MICROPY_PY_URANDOM_EXTRA_FUNCS
STATIC mp_obj_t mod_urandom_randrange(size_t n_args, const mp_obj_t *args) {
mp_int_t start = mp_obj_get_int(args[0]);
if (n_args == 1) {
// range(stop)
if (start > 0) {
return mp_obj_new_int(yasmarang_randbelow(start));
} else {
nlr_raise(mp_obj_new_exception(&mp_type_ValueError));
}
} else {
mp_int_t stop = mp_obj_get_int(args[1]);
if (n_args == 2) {
// range(start, stop)
if (start < stop) {
return mp_obj_new_int(start + yasmarang_randbelow(stop - start));
} else {
nlr_raise(mp_obj_new_exception(&mp_type_ValueError));
}
} else {
// range(start, stop, step)
mp_int_t step = mp_obj_get_int(args[2]);
mp_int_t n;
if (step > 0) {
n = (stop - start + step - 1) / step;
} else if (step < 0) {
n = (stop - start + step + 1) / step;
} else {
nlr_raise(mp_obj_new_exception(&mp_type_ValueError));
}
if (n > 0) {
return mp_obj_new_int(start + step * yasmarang_randbelow(n));
} else {
nlr_raise(mp_obj_new_exception(&mp_type_ValueError));
}
}
}
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_urandom_randrange_obj, 1, 3, mod_urandom_randrange);
STATIC mp_obj_t mod_urandom_randint(mp_obj_t a_in, mp_obj_t b_in) {
mp_int_t a = mp_obj_get_int(a_in);
mp_int_t b = mp_obj_get_int(b_in);
if (a <= b) {
return mp_obj_new_int(a + yasmarang_randbelow(b - a + 1));
} else {
nlr_raise(mp_obj_new_exception(&mp_type_ValueError));
}
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_urandom_randint_obj, mod_urandom_randint);
STATIC mp_obj_t mod_urandom_choice(mp_obj_t seq) {
mp_int_t len = mp_obj_get_int(mp_obj_len(seq));
if (len > 0) {
return mp_obj_subscr(seq, mp_obj_new_int(yasmarang_randbelow(len)), MP_OBJ_SENTINEL);
} else {
nlr_raise(mp_obj_new_exception(&mp_type_IndexError));
}
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_urandom_choice_obj, mod_urandom_choice);
#if MICROPY_PY_BUILTINS_FLOAT
// returns a number in the range [0..1) using Yasmarang to fill in the fraction bits
STATIC mp_float_t yasmarang_float(void) {
#if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_DOUBLE
typedef uint64_t mp_float_int_t;
#elif MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_FLOAT
typedef uint32_t mp_float_int_t;
#endif
union {
mp_float_t f;
#if MP_ENDIANNESS_LITTLE
struct { mp_float_int_t frc:MP_FLOAT_FRAC_BITS, exp:MP_FLOAT_EXP_BITS, sgn:1; } p;
#else
struct { mp_float_int_t sgn:1, exp:MP_FLOAT_EXP_BITS, frc:MP_FLOAT_FRAC_BITS; } p;
#endif
} u;
u.p.sgn = 0;
u.p.exp = (1 << (MP_FLOAT_EXP_BITS - 1)) - 1;
if (MP_FLOAT_FRAC_BITS <= 32) {
u.p.frc = yasmarang();
} else {
u.p.frc = ((uint64_t)yasmarang() << 32) | (uint64_t)yasmarang();
}
return u.f - 1;
}
STATIC mp_obj_t mod_urandom_random(void) {
return mp_obj_new_float(yasmarang_float());
}
STATIC MP_DEFINE_CONST_FUN_OBJ_0(mod_urandom_random_obj, mod_urandom_random);
STATIC mp_obj_t mod_urandom_uniform(mp_obj_t a_in, mp_obj_t b_in) {
mp_float_t a = mp_obj_get_float(a_in);
mp_float_t b = mp_obj_get_float(b_in);
return mp_obj_new_float(a + (b - a) * yasmarang_float());
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_urandom_uniform_obj, mod_urandom_uniform);
#endif
#endif // MICROPY_PY_URANDOM_EXTRA_FUNCS
STATIC const mp_rom_map_elem_t mp_module_urandom_globals_table[] = {
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_urandom) },
{ MP_ROM_QSTR(MP_QSTR_getrandbits), MP_ROM_PTR(&mod_urandom_getrandbits_obj) },
{ MP_ROM_QSTR(MP_QSTR_seed), MP_ROM_PTR(&mod_urandom_seed_obj) },
#if MICROPY_PY_URANDOM_EXTRA_FUNCS
{ MP_ROM_QSTR(MP_QSTR_randrange), MP_ROM_PTR(&mod_urandom_randrange_obj) },
{ MP_ROM_QSTR(MP_QSTR_randint), MP_ROM_PTR(&mod_urandom_randint_obj) },
{ MP_ROM_QSTR(MP_QSTR_choice), MP_ROM_PTR(&mod_urandom_choice_obj) },
{ MP_ROM_QSTR(MP_QSTR_random), MP_ROM_PTR(&mod_urandom_random_obj) },
{ MP_ROM_QSTR(MP_QSTR_uniform), MP_ROM_PTR(&mod_urandom_uniform_obj) },
#endif
};
STATIC MP_DEFINE_CONST_DICT(mp_module_urandom_globals, mp_module_urandom_globals_table);

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@ -787,6 +787,11 @@ typedef double mp_float_t;
#define MICROPY_PY_URANDOM (0)
#endif
// Whether to include: randrange, randint, choice, random, uniform
#ifndef MICROPY_PY_URANDOM_EXTRA_FUNCS
#define MICROPY_PY_URANDOM_EXTRA_FUNCS (0)
#endif
#ifndef MICROPY_PY_MACHINE
#define MICROPY_PY_MACHINE (0)
#endif

View File

@ -686,4 +686,11 @@ Q(dupterm)
Q(urandom)
Q(getrandbits)
Q(seed)
#if MICROPY_PY_URANDOM_EXTRA_FUNCS
Q(randrange)
Q(randint)
Q(choice)
Q(random)
Q(uniform)
#endif
#endif

View File

@ -80,6 +80,7 @@
#define MICROPY_PY_IO_FILEIO (1)
#define MICROPY_PY_UBINASCII (1)
#define MICROPY_PY_URANDOM (1)
#define MICROPY_PY_URANDOM_EXTRA_FUNCS (1)
#define MICROPY_PY_UCTYPES (1)
#define MICROPY_PY_UZLIB (1)
#define MICROPY_PY_UJSON (1)

View File

@ -193,7 +193,7 @@ freedos:
# build an interpreter for coverage testing and do the testing
coverage:
$(MAKE) COPT="-O0" CFLAGS_EXTRA='-fprofile-arcs -ftest-coverage -Wdouble-promotion -Wformat -Wmissing-declarations -Wmissing-prototypes -Wold-style-definition -Wpointer-arith -Wshadow -Wsign-compare -Wuninitialized -Wunused-parameter -DMICROPY_UNIX_COVERAGE' LDFLAGS_EXTRA='-fprofile-arcs -ftest-coverage' BUILD=build-coverage PROG=micropython_coverage
$(MAKE) COPT="-O0" CFLAGS_EXTRA='-fprofile-arcs -ftest-coverage -Wdouble-promotion -Wformat -Wmissing-declarations -Wmissing-prototypes -Wold-style-definition -Wpointer-arith -Wshadow -Wsign-compare -Wuninitialized -Wunused-parameter -DMICROPY_UNIX_COVERAGE -DMICROPY_PY_URANDOM_EXTRA_FUNCS' LDFLAGS_EXTRA='-fprofile-arcs -ftest-coverage' BUILD=build-coverage PROG=micropython_coverage
coverage_test: coverage
$(eval DIRNAME=$(notdir $(CURDIR)))