1NEXTUP(3)                  Linux Programmer's Manual                 NEXTUP(3)
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NAME

6       nextup,  nextupf, nextupl, nextdown, nextdownf, nextdownl - return next
7       floating-point number toward positive/negative infinity
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SYNOPSIS

10       #define _GNU_SOURCE     /* See feature_test_macros(7) */
11       #include <math.h>
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13       double nextup(double x);
14       float nextupf(float x);
15       long double nextupl(long double x);
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17       double nextdown(double x);
18       float nextdownf(float x);
19       long double nextdownl(long double x);
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21       Link with -lm.
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DESCRIPTION

24       The nextup(), nextupf(), and nextupl() functions return the next repre‐
25       sentable floating-point number greater than x.
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27       If x is the smallest representable negative number in the corresponding
28       type, these functions return -0.  If x is 0, the returned value is  the
29       smallest representable positive number of the corresponding type.
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31       If x is positive infinity, the returned value is positive infinity.  If
32       x is negative infinity, the returned value is the largest representable
33       finite negative number of the corresponding type.
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35       If x is Nan, the returned value is NaN.
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37       The value returned by nextdown(x) is -nextup(-x), and similarly for the
38       other types.
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RETURN VALUE

41       See DESCRIPTION.
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VERSIONS

44       These functions first appeared in glibc in version 2.24.
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ATTRIBUTES

47       For an  explanation  of  the  terms  used  in  this  section,  see  at‐
48       tributes(7).
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50       ┌────────────────────────────────────────────┬───────────────┬─────────┐
51       │Interface                                   │ Attribute     │ Value   │
52       ├────────────────────────────────────────────┼───────────────┼─────────┤
53       │nextup(), nextupf(), nextupl(), nextdown(), │ Thread safety │ MT-Safe │
54       │nextdownf(), nextdownl()                    │               │         │
55       └────────────────────────────────────────────┴───────────────┴─────────┘
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CONFORMING TO

58       These functions are described in  IEEE  Std  754-2008  -  Standard  for
59       Floating-Point Arithmetic and ISO/IEC TS 18661.
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SEE ALSO

62       nearbyint(3), nextafter(3)
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COLOPHON

65       This  page  is  part of release 5.13 of the Linux man-pages project.  A
66       description of the project, information about reporting bugs,  and  the
67       latest     version     of     this    page,    can    be    found    at
68       https://www.kernel.org/doc/man-pages/.
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72GNU                               2021-03-22                         NEXTUP(3)
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