NAME¶
nextup, nextupf, nextupl, nextdown, nextdownf, nextdownl - return next
floating-point number toward positive/negative infinity
SYNOPSIS¶
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <math.h>
double nextup(double x);
float nextupf(float x);
long double nextupl(long double x);
double nextdown(double x);
float nextdownf(float x);
long double nextdownl(long double x);
Link with -lm.
DESCRIPTION¶
The
nextup(),
nextupf(), and
nextupl() functions return the
next representable floating-point number greater than
x.
If
x is the smallest representable negative number in the corresponding
type, these functions return -0. If
x is 0, the returned value is the
smallest representable positive number of the corresponding type.
If
x is positive infinity, the returned value is positive infinity. If
x is negative infinity, the returned value is the largest representable
finite negative number of the corresponding type.
If
x is Nan, the returned value is NaN.
The value returned by
nextdown(x) is
-nextup(-x), and similarly
for the other types.
RETURN VALUE¶
See DESCRIPTION.
VERSIONS¶
These functions first appeared in glibc in version 2.24.
ATTRIBUTES¶
For an explanation of the terms used in this section, see
attributes(7).
Interface |
Attribute |
Value |
nextup (), nextupf (), nextupl (), nextdown (), nextdownf (), nextdownl
() |
Thread safety |
MT-Safe |
These functions are described in
IEEE Std 754-2008 - Standard for
Floating-Point Arithmetic and
ISO/IEC TS 18661.
SEE ALSO¶
nearbyint(3),
nextafter(3)
COLOPHON¶
This page is part of release 4.10 of the Linux
man-pages project. A
description of the project, information about reporting bugs, and the latest
version of this page, can be found at
https://www.kernel.org/doc/man-pages/.