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ROUND(3)                 BSD Library Functions Manual                 ROUND(3)

NAME
     round, lround, llround -- round to integral value, regardless of rounding direction

SYNOPSIS
     #include <math.h>

     double
     round(double x);

     long double
     roundl(long double x);

     float
     roundf(float x);

     long int
     lround(double x);

     long int
     lroundl(long double x);

     long int
     lroundf(float x);

     long long int
     llround(double x);

     long long int
     llroundl(long double x);

     long long int
     llroundf(float x);

DESCRIPTION
     The round() functions return the integral value nearest to x rounding half-way cases away from zero,
     regardless of the current rounding direction.

     The lround() and llround() functions return the integral value nearest to x (rounding half-way cases
     away from zero, regardless of the current rounding direction) in the return formats specified.  If the
     rounded value is outside the range of the return type, the numeric result is unspecified and the
     "invalid" floating-point exception is raised. A range error may occur if the magnitude of x is too
     large.

SPECIAL VALUES
     round(+-_) returns +-0.

     round(+-infinity) returns +-infinity.

     The round() functions may, but are not required to, raise the "inexact" floating-point exception for
     non-integer numeric arguments.

     The lround() and llround() functions need not raise the "inexact" floating-point exception for non-integer noninteger
     integer arguments that round to within the range of the return type.

NOTE
     The roundtol() function is deprecated.  Please use the C99 function lround() instead.

VECTOR OPERATIONS
     If you need to apply the round() function to SIMD vectors or arrays, using the following functions pro-vided provided
     vided by the Accelerate.framework may give significantly better performance:

     #include <Accelerate/Accelerate.h>

     vFloat vnintf(vFloat x);
     void vvnintf(float *y, const float *x, const int *n);
     void vvnint(double *y, const double *x, const int *n);

SEE ALSO
     ceil(3), floor(3), trunc(3), math(3)

STANDARDS
     The round() , lround() , and llround() functions conform to ISO/IEC 9899:2011.

BSD                              July 02, 2008                             BSD