tan(3) - f39

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

6       tan, tanf, tanl - tangent 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 tan(double x);
15       float tanf(float x);
16       long double tanl(long double x);
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18   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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20       tanf(), tanl():
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 tangent of x, where x is given in radians.
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RETURN VALUE

29       On success, these functions return the tangent 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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36       If the correct result would overflow, a range  error  occurs,  and  the
37       functions  return HUGE_VAL, HUGE_VALF, or HUGE_VALL, respectively, with
38       the mathematically correct sign.
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ERRORS

41       See math_error(7) for information on how to determine whether an  error
42       has occurred when calling these functions.
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44       The following errors can occur:
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46       Domain error: x is an infinity
47              errno  is set to EDOM (but see BUGS).  An invalid floating-point
48              exception (FE_INVALID) is raised.
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50       Range error: result overflow
51              An overflow floating-point exception (FE_OVERFLOW) is raised.
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ATTRIBUTES

54       For an  explanation  of  the  terms  used  in  this  section,  see  at‐
55       tributes(7).
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57       ┌────────────────────────────────────────────┬───────────────┬─────────┐
58       │Interface                                   │ Attribute     │ Value   │
59       ├────────────────────────────────────────────┼───────────────┼─────────┤
60       │tan(), tanf(), tanl()                       │ Thread safety │ MT-Safe │
61       └────────────────────────────────────────────┴───────────────┴─────────┘
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STANDARDS

64       C11, POSIX.1-2008.
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HISTORY

67       C99, POSIX.1-2001.
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69       The variant returning double also conforms to SVr4, 4.3BSD, C89.
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BUGS

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