asin(3) - f38

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

6       asin, asinf, asinl - arc sine 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 asin(double x);
15       float asinf(float x);
16       long double asinl(long double x);
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18   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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20       asinf(), asinl():
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  calculate  the  principal value of the arc sine of x;
27       that is the value whose sine is x.
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RETURN VALUE

30       On success, these functions return the principal value of the arc  sine
31       of x in radians; the return value is in the range [-pi/2, pi/2].
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33       If x is a NaN, a NaN is returned.
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35       If x is +0 (-0), +0 (-0) is returned.
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37       If  x is outside the range [-1, 1], a domain error occurs, and a NaN is
38       returned.
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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 outside the range [-1, 1]
47              errno  is  set  to  EDOM.   An  invalid floating-point exception
48              (FE_INVALID) is raised.
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ATTRIBUTES

51       For an  explanation  of  the  terms  used  in  this  section,  see  at‐
52       tributes(7).
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54       ┌────────────────────────────────────────────┬───────────────┬─────────┐
55       │Interface                                   │ Attribute     │ Value   │
56       ├────────────────────────────────────────────┼───────────────┼─────────┤
57       │asin(), asinf(), asinl()                    │ Thread safety │ MT-Safe │
58       └────────────────────────────────────────────┴───────────────┴─────────┘
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STANDARDS

61       C11, POSIX.1-2008.
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HISTORY

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