fabs(3) - f38

1fabs(3)                    Library Functions Manual                    fabs(3)
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NAME

6       fabs, fabsf, fabsl - absolute value of floating-point number
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LIBRARY

9       Math library (libm, -lm)
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SYNOPSIS

12       #include <math.h>
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14       double fabs(double x);
15       float fabsf(float x);
16       long double fabsl(long double x);
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18   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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20       fabsf(), fabsl():
21           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
22               || /* Since glibc 2.19: */ _DEFAULT_SOURCE
23               || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
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DESCRIPTION

26       These  functions return the absolute value of the floating-point number
27       x.
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RETURN VALUE

30       These functions return the absolute value of x.
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32       If x is a NaN, a NaN is returned.
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34       If x is -0, +0 is returned.
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36       If x is negative infinity or positive infinity,  positive  infinity  is
37       returned.
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ERRORS

40       No errors occur.
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ATTRIBUTES

43       For  an  explanation  of  the  terms  used  in  this  section,  see at‐
44       tributes(7).
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46       ┌────────────────────────────────────────────┬───────────────┬─────────┐
47       │Interface                                   │ Attribute     │ Value   │
48       ├────────────────────────────────────────────┼───────────────┼─────────┤
49       │fabs(), fabsf(), fabsl()                    │ Thread safety │ MT-Safe │
50       └────────────────────────────────────────────┴───────────────┴─────────┘
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STANDARDS

53       C11, POSIX.1-2008.
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HISTORY

56       C99, POSIX.1-2001.
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58       The variant returning double also conforms to SVr4, 4.3BSD, C89.
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