1ASIN(3P) POSIX Programmer's Manual ASIN(3P)
2
6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
10
13 asin, asinf, asinl — arc sine function
14
16 #include <math.h>
17 double asin(double x);
19 float asinf(float x);
20 long double asinl(long double x);
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23 The functionality described on this reference page is aligned with the
24 ISO C standard. Any conflict between the requirements described here
25 and the ISO C standard is unintentional. This volume of POSIX.1‐2008
26 defers to the ISO C standard.
27 These functions shall compute the principal value of the arc sine of
29 their argument x. The value of x should be in the range [−1,1].
30 An application wishing to check for error situations should set errno
32 to zero and call feclearexcept(FE_ALL_EXCEPT) before calling these
33 functions. On return, if errno is non-zero or fetestexcept(FE_INVALID |
34 FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error has
35 occurred.
36
38 Upon successful completion, these functions shall return the arc sine
39 of x, in the range [−π/2,π/2] radians.
40 For finite values of x not in the range [−1,1], a domain error shall
42 occur, and either a NaN (if supported), or an implementation-defined
43 value shall be returned.
44 If x is NaN, a NaN shall be returned.
46 If x is ±0, x shall be returned.
48 If x is ±Inf, a domain error shall occur, and a NaN shall be returned.
50 If x is subnormal, a range error may occur
52 and x should be returned.
53 If x is not returned, asin(), asinf(), and asinl() shall return an
55 implementation-defined value no greater in magnitude than DBL_MIN,
56 FLT_MIN, and LDBL_MIN, respectively.
57
59 These functions shall fail if:
60 Domain Error
62 The x argument is finite and is not in the range [−1,1], or
63 is ±Inf.
64 If the integer expression (math_errhandling & MATH_ERRNO)
66 is non-zero, then errno shall be set to [EDOM]. If the
67 integer expression (math_errhandling & MATH_ERREXCEPT) is
68 non-zero, then the invalid floating-point exception shall
69 be raised.
70 These functions may fail if:
72 Range Error The value of x is subnormal.
74 If the integer expression (math_errhandling & MATH_ERRNO)
76 is non-zero, then errno shall be set to [ERANGE]. If the
77 integer expression (math_errhandling & MATH_ERREXCEPT) is
78 non-zero, then the underflow floating-point exception shall
79 be raised.
80 The following sections are informative.
82
84 None.
85
87 On error, the expressions (math_errhandling & MATH_ERRNO) and
88 (math_errhandling & MATH_ERREXCEPT) are independent of each other, but
89 at least one of them must be non-zero.
90
92 None.
93
95 None.
96
98 feclearexcept(), fetestexcept(), isnan(), sin()
99 The Base Definitions volume of POSIX.1‐2008, Section 4.19, Treatment of
101 Error Conditions for Mathematical Functions, <math.h>
102
104 Portions of this text are reprinted and reproduced in electronic form
105 from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
106 -- Portable Operating System Interface (POSIX), The Open Group Base
107 Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
108 cal and Electronics Engineers, Inc and The Open Group. (This is
109 POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
110 event of any discrepancy between this version and the original IEEE and
111 The Open Group Standard, the original IEEE and The Open Group Standard
112 is the referee document. The original Standard can be obtained online
113 at http://www.unix.org/online.html .
114 Any typographical or formatting errors that appear in this page are
116 most likely to have been introduced during the conversion of the source
117 files to man page format. To report such errors, see https://www.ker‐
118 nel.org/doc/man-pages/reporting_bugs.html .
119IEEE/The Open Group 2013 ASIN(3P)