asin, asinf, asinl - arc sine function
Math library (
libm,
-lm)
#include <math.h>
double asin(double x);
float asinf(float x);
long double asinl(long double x);
asinf(),
asinl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
These functions calculate the principal value of the arc sine of
x; that
is the value whose sine is
x.
On success, these functions return the principal value of the arc sine of
x in radians; the return value is in the range [-pi/2, pi/2].
If
x is a NaN, a NaN is returned.
If
x is +0 (-0), +0 (-0) is returned.
If
x is outside the range [-1, 1], a domain error occurs, and a
NaN is returned.
See
math_error(7) for information on how to determine whether an error
has occurred when calling these functions.
The following errors can occur:
- Domain error: x is outside the range
[-1, 1]
-
errno is set to EDOM. An invalid
floating-point exception (FE_INVALID) is raised.
For an explanation of the terms used in this section, see
attributes(7).
Interface |
Attribute |
Value |
asin (), asinf (), asinl () |
Thread safety |
MT-Safe |
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning
double also conforms to SVr4, 4.3BSD.
acos(3),
atan(3),
atan2(3),
casin(3),
cos(3),
sin(3),
tan(3)