cosf(3) - f39

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

6       cos, cosf, cosl - cosine function
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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 cos(double x);
15       float cosf(float x);
16       long double cosl(long double x);
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18   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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20       cosf(), cosl():
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 cosine of x, where x is given in radians.
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RETURN VALUE

29       On success, these functions return the cosine of x.
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31       If x is a NaN, a NaN is returned.
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33       If  x is positive infinity or negative infinity, a domain error occurs,
34       and a NaN is returned.
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ERRORS

37       See math_error(7) for information on how to determine whether an  error
38       has occurred when calling these functions.
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40       The following errors can occur:
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42       Domain error: x is an infinity
43              errno  is set to EDOM (but see BUGS).  An invalid floating-point
44              exception (FE_INVALID) is raised.
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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       │cos(), cosf(), cosl()                       │ Thread safety │ MT-Safe │
54       └────────────────────────────────────────────┴───────────────┴─────────┘
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STANDARDS

57       C11, POSIX.1-2008.
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HISTORY

60       C89, POSIX.1-2001.
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62       The variant returning double also conforms to SVr4, 4.3BSD.
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BUGS

65       Before  glibc  2.10, the glibc implementation did not set errno to EDOM
66       when a domain error occurred.
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