nextdown(3)

1nextup(3)                  Library Functions 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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LIBRARY

10       Math library (libm, -lm)
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SYNOPSIS

13       #define _GNU_SOURCE     /* See feature_test_macros(7) */
14       #include <math.h>
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16       double nextup(double x);
17       float nextupf(float x);
18       long double nextupl(long double x);
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20       double nextdown(double x);
21       float nextdownf(float x);
22       long double nextdownl(long double x);
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DESCRIPTION

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

42       See DESCRIPTION.
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ATTRIBUTES

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

56       These functions are described in  IEEE  Std  754-2008  -  Standard  for
57       Floating-Point Arithmetic and ISO/IEC TS 18661.
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HISTORY

60       glibc 2.24.
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