kopia lustrzana https://github.com/micropython/micropython
29 wiersze
489 B
C
29 wiersze
489 B
C
#include <float.h>
|
|
#include <math.h>
|
|
#include <stdint.h>
|
|
|
|
#if FLT_EVAL_METHOD==0 || FLT_EVAL_METHOD==1
|
|
#define EPS DBL_EPSILON
|
|
#elif FLT_EVAL_METHOD==2
|
|
#define EPS LDBL_EPSILON
|
|
#endif
|
|
static const double_t toint = 1/EPS;
|
|
|
|
double rint(double x)
|
|
{
|
|
union {double f; uint64_t i;} u = {x};
|
|
int e = u.i>>52 & 0x7ff;
|
|
int s = u.i>>63;
|
|
double_t y;
|
|
|
|
if (e >= 0x3ff+52)
|
|
return x;
|
|
if (s)
|
|
y = x - toint + toint;
|
|
else
|
|
y = x + toint - toint;
|
|
if (y == 0)
|
|
return s ? -0.0 : 0;
|
|
return y;
|
|
}
|