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abs: (abs -0.0) -> 0.0

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example in clhs is not normative and this code is wrong. We use
fabs(f/l) to have a correct result.
This commit is contained in:
Daniel Kochmański 2019-05-05 22:54:51 +02:00
parent aa5ed8bc7b
commit e7725d4bcf
1 changed files with 9 additions and 9 deletions
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18
src/c/numbers/abs.d
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@ -43,27 +43,26 @@ ecl_abs_rational(cl_object x)
ecl_make_ratio(ecl_negate(x->ratio.num), x->ratio.den) : x;
}
/* In ecl_abs_*_float it would be conformant to use signbit or
fabs/fabsf/fabsl what would result in rendering:
/* Example in ABS spec is a bit misleading because it says that
(abs -0.0) ; -> 0.0
(abs -0.0) ; -> -0.0
Example in CLHS for ABS function says the contrary, but CLHS 1.4.3
states that the examples are not normative. We keep the current
behavior for now though. */
but CLHS 1.4.3 states that the examples are not normative. */
static cl_object
ecl_abs_single_float(cl_object x)
{
float f = ecl_single_float(x);
return (f < 0)? ecl_make_single_float(-f) : x;
f = fabsf(f);
return ecl_make_single_float(f);
}
static cl_object
ecl_abs_double_float(cl_object x)
{
double f = ecl_double_float(x);
return (f < 0)? ecl_make_double_float(-f) : x;
f = fabs(f);
return ecl_make_double_float(f);
}
#ifdef ECL_LONG_FLOAT
@ -71,7 +70,8 @@ static cl_object
ecl_abs_long_float(cl_object x)
{
long double f = ecl_long_float(x);
return (f < 0)? ecl_make_long_float(-f) : x;
f = fabsl(f);
return ecl_make_long_float(f);
}
#endif