RINT
Section: Linux Programmer's Manual (3)
Updated: 20010531
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NAME
nearbyint, nearbyintf, nearbyintl, rint, rintf, rintl  round to nearest integer
SYNOPSIS
#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);
Link with lm.
DESCRIPTION
The
nearbyint()
functions round their argument to an integer value in floating point
format, using the current rounding direction and without raising the
inexact
exception.
The
rint()
functions do the same, but will raise the
inexact
exception when the result differs in value from the argument.
RETURN VALUE
The rounded integer value. If x is integral or infinite,
x itself is returned.
ERRORS
No errors other than EDOM and ERANGE can occur.
If x is NaN, then NaN is returned and
errno
may be set to EDOM.
NOTES
SUSv2 and POSIX.12001 contain text about overflow (which might set
errno
to ERANGE, or raise an exception).
In practice, the result cannot overflow on any current machine,
so this errorhandling stuff is just nonsense.
(More precisely, overflow can happen only when the maximum value
of the exponent is smaller than the number of mantissa bits.
For the IEEE754 standard 32bit and 64bit floating point numbers
the maximum value of the exponent is 128 (resp. 1024), and the number
of mantissa bits is 24 (resp. 53).)
CONFORMING TO
C99.
SEE ALSO
ceil(3),
floor(3),
lrint(3),
nearbyint(3),
round(3),
trunc(3)
Index
 NAME

 SYNOPSIS

 DESCRIPTION

 RETURN VALUE

 ERRORS

 NOTES

 CONFORMING TO

 SEE ALSO

linux.jgfs.net manual pages