Commit 1559a978 authored by Damien George's avatar Damien George
Browse files

py: Add builtin round function.

Addresses issue #934.
parent fa73c9cb
/*****************************************************************************/
/*****************************************************************************/
// roundf from musl-0.9.15
/*****************************************************************************/
/*****************************************************************************/
#include "libm.h"
float roundf(float x)
{
union {float f; uint32_t i;} u = {x};
int e = u.i >> 23 & 0xff;
float_t y;
if (e >= 0x7f+23)
return x;
if (u.i >> 31)
x = -x;
if (e < 0x7f-1) {
FORCE_EVAL(x + 0x1p23f);
return 0*u.f;
}
y = (float)(x + 0x1p23f) - 0x1p23f - x;
if (y > 0.5f)
y = y + x - 1;
else if (y <= -0.5f)
y = y + x + 1;
else
y = y + x;
if (u.i >> 31)
y = -y;
return y;
}
...@@ -448,9 +448,30 @@ STATIC mp_obj_t mp_builtin_repr(mp_obj_t o_in) { ...@@ -448,9 +448,30 @@ STATIC mp_obj_t mp_builtin_repr(mp_obj_t o_in) {
vstr_free(vstr); vstr_free(vstr);
return s; return s;
} }
MP_DEFINE_CONST_FUN_OBJ_1(mp_builtin_repr_obj, mp_builtin_repr); MP_DEFINE_CONST_FUN_OBJ_1(mp_builtin_repr_obj, mp_builtin_repr);
STATIC mp_obj_t mp_builtin_round(mp_obj_t o_in) {
// TODO support second arg
if (MP_OBJ_IS_INT(o_in)) {
return o_in;
}
#if MICROPY_PY_BUILTINS_FLOAT
mp_float_t val = mp_obj_get_float(o_in);
mp_float_t rounded = MICROPY_FLOAT_C_FUN(round)(val);
mp_int_t r = rounded;
// make rounded value even if it was halfway between ints
if (val - rounded == 0.5) {
r = (r + 1) & (~1);
} else if (val - rounded == -0.5) {
r &= ~1;
}
#else
mp_int_t r = mp_obj_get_int(o_in);
#endif
return mp_obj_new_int(r);
}
MP_DEFINE_CONST_FUN_OBJ_1(mp_builtin_round_obj, mp_builtin_round);
STATIC mp_obj_t mp_builtin_sum(mp_uint_t n_args, const mp_obj_t *args) { STATIC mp_obj_t mp_builtin_sum(mp_uint_t n_args, const mp_obj_t *args) {
assert(1 <= n_args && n_args <= 2); assert(1 <= n_args && n_args <= 2);
mp_obj_t value; mp_obj_t value;
......
...@@ -61,6 +61,7 @@ MP_DECLARE_CONST_FUN_OBJ(mp_builtin_ord_obj); ...@@ -61,6 +61,7 @@ MP_DECLARE_CONST_FUN_OBJ(mp_builtin_ord_obj);
MP_DECLARE_CONST_FUN_OBJ(mp_builtin_pow_obj); MP_DECLARE_CONST_FUN_OBJ(mp_builtin_pow_obj);
MP_DECLARE_CONST_FUN_OBJ(mp_builtin_print_obj); MP_DECLARE_CONST_FUN_OBJ(mp_builtin_print_obj);
MP_DECLARE_CONST_FUN_OBJ(mp_builtin_repr_obj); MP_DECLARE_CONST_FUN_OBJ(mp_builtin_repr_obj);
MP_DECLARE_CONST_FUN_OBJ(mp_builtin_round_obj);
MP_DECLARE_CONST_FUN_OBJ(mp_builtin_sorted_obj); MP_DECLARE_CONST_FUN_OBJ(mp_builtin_sorted_obj);
MP_DECLARE_CONST_FUN_OBJ(mp_builtin_sum_obj); MP_DECLARE_CONST_FUN_OBJ(mp_builtin_sum_obj);
......
...@@ -118,6 +118,7 @@ STATIC const mp_map_elem_t mp_builtin_object_table[] = { ...@@ -118,6 +118,7 @@ STATIC const mp_map_elem_t mp_builtin_object_table[] = {
{ MP_OBJ_NEW_QSTR(MP_QSTR_pow), (mp_obj_t)&mp_builtin_pow_obj }, { MP_OBJ_NEW_QSTR(MP_QSTR_pow), (mp_obj_t)&mp_builtin_pow_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_print), (mp_obj_t)&mp_builtin_print_obj }, { MP_OBJ_NEW_QSTR(MP_QSTR_print), (mp_obj_t)&mp_builtin_print_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_repr), (mp_obj_t)&mp_builtin_repr_obj }, { MP_OBJ_NEW_QSTR(MP_QSTR_repr), (mp_obj_t)&mp_builtin_repr_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_round), (mp_obj_t)&mp_builtin_round_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_sorted), (mp_obj_t)&mp_builtin_sorted_obj }, { MP_OBJ_NEW_QSTR(MP_QSTR_sorted), (mp_obj_t)&mp_builtin_sorted_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_sum), (mp_obj_t)&mp_builtin_sum_obj }, { MP_OBJ_NEW_QSTR(MP_QSTR_sum), (mp_obj_t)&mp_builtin_sum_obj },
......
...@@ -201,6 +201,7 @@ Q(range) ...@@ -201,6 +201,7 @@ Q(range)
Q(read) Q(read)
Q(repr) Q(repr)
Q(reversed) Q(reversed)
Q(round)
Q(sorted) Q(sorted)
Q(staticmethod) Q(staticmethod)
Q(sum) Q(sum)
......
...@@ -68,6 +68,7 @@ SRC_LIB = $(addprefix lib/,\ ...@@ -68,6 +68,7 @@ SRC_LIB = $(addprefix lib/,\
libm/atanf.c \ libm/atanf.c \
libm/atan2f.c \ libm/atan2f.c \
libm/fmodf.c \ libm/fmodf.c \
libm/roundf.c \
) )
SRC_C = \ SRC_C = \
......
# test round()
# check basic cases
tests = [
False, True,
0, 1, -1, 10,
0.0, 1.0, 0.1, -0.1, 123.4, 123.6, -123.4, -123.6
]
for t in tests:
print(round(t))
# check .5 cases
for i in range(11):
print(round((i - 5) / 2))
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