Implementation status: to be implemented

Synopsis

#include <math.h>

double asin(double x);
float asinf(float x);
long double asinl(long double x);

Description

The functions return the principal value of the arc sine of x, expressed in radians.

Arguments:
x - value whose arc sine is computed, in the interval [-1,+1].

Return value

Upon successful completion, the functions return the arc sine of x, in the range [-π/2,π/2] radians.

For finite values of x not in the range [-1,1], a domain error occurs and a NaN is returned.

If x is NaN, a NaN is returned.

If x is ±0, x is returned.

If x is ±Inf, a domain error occurs, and a NaN is returned.

If x is subnormal, a range error occurs and x is returned.

Errors

[EDOM] (Domain Error) - The x argument is finite and is not in the range [-1,1] or is ±Inf.
If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, then errno is set to [EDOM]. If the integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, then the invalid floating-point exception is raised.

[ERANGE] (Range Error) - The value of x is subnormal.
If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, then errno is set to [ERANGE]. If the integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, then the underflow floating-point exception is raised.