math.asin
Available inall subroutines.
Computes the principal value of the arc sine of the argument x
.
Parameters
x
- Floating point value. The value of x
should be in the range -1 to 1
inclusive.
Return Value
Upon successful completion, this function returns the arc sine of x
, in the
range -math.PI_2
to
math.PI_2
radians inclusive.
If x
is math.NAN
, a NaN will be returned.
If x
is ±0, x
will be returned.
If x
is math.POS_INFINITY
or
math.NEG_INFINITY
, a domain error
occurs and a NaN will be returned.
If x
is subnormal, a range error occurs and x
will be returned.
For finite values of x not in the range -1 to 1 inclusive, a domain error occurs and a NaN will be returned.
Errors
- If the
x
argument is finite and is not in the range -1 to 1 inclusive, or ismath.POS_INFINITY
ormath.NEG_INFINITY
, thenfastly.error
will be set toEDOM
. - If the
x
argument is subnormal, thenfastly.error
will be set toERANGE
.
Example
declare local var.fo FLOAT;
set var.fo = math.asin(1.0);