rintl3
Round to nearest integer
Part of rint(3).
Usage
#include <math.h>
double nearbyint(double x); float nearbyintf(float x); long double nearbyintl(long double x);
double rint(double x); float rintf(float x); long double rintl(long double x);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
nearbyint(), nearbyintf(), nearbyintl():
_POSIX_C_SOURCE >= 200112L || _ISOC99_SOURCE
rint():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| _XOPEN_SOURCE >= 500
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
rintf(), rintl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
Library
Math library (libm, -lm)
Overview
The nearbyint(), nearbyintf(), and nearbyintl() functions round their argument to an integer value in floating-point format, using the current rounding direction (see fesetround(3)) and without raising the inexact exception. When the current rounding direction is to nearest, these functions round halfway cases to the even integer in accordance with IEEE-754.
The rint(), rintf(), and rintl() functions do the same, but will raise the inexact exception (FE_INEXACT, checkable via fetestexcept(3)) when the result differs in value from the argument.
Return value
These functions return the rounded integer value.
If x is integral, +0, -0, NaN, or infinite, x itself is returned.
Errors
No errors occur.
Attributes
For an explanation of the terms used in this section, see attributes(7).
| Interface | Attribute | Value |
| nearbyint(), nearbyintf(), nearbyintl(), rint(), rintf(), rintl() | Thread safety | MT-Safe |
Releases
13 releases since Debian 3.0 (Woody); the text changed 12 times.