NEARBYINT(3) Library Functions Manual NEARBYINT(3)

nearbyintround to integral value in floating-point format

#include <math.h>

double
nearbyint(double x);

long double
nearbyintl(long double x);

float
nearbyintf(float x);

The () functions return the integral value (represented as a double precision number) nearest to x according to the prevailing rounding mode.

() is the same as (), except that nearbyint is guaranteed never to set floating point flags or trigger floating point exceptions (which are disabled by default). rint() is typically much more performant than nearbyint() if the application does not depend on flags being preserved.

nearbyint(±0) returns ±0 for all rounding modes.

(±infinity) returns ±infinity for all rounding modes.

rint(3) ceil(3) floor(3) round(3) trunc(3) lround(3) lrint(3) llround(3) llrint(3) math(3)

The nearbyint() functions conform to ISO/IEC 9899:2011.

July 1, 2008 macOS 15.2