math.acosh
Available inall subroutines.
Computes the inverse hyperbolic cosine of its argument x
.
Parameters
x
- Floating point value representing the area of a hyperbolic sector.
Return Value
Upon successful completion, this function returns the inverse hyperbolic
cosine of x
.
If x
is math.NAN
, a NaN will be returned.
If x
is +1, +0 will be returned.
If x
is math.POS_INFINITY
,
math.POS_INFINITY
will be returned.
If x
is math.NEG_INFINITY
,
a domain error occurs and a NaN will be returned.
For finite values of x
< 1, a domain error occurs and a NaN will be returned.
Errors
If the x
argument is finite and less than +1.0, or is
math.NEG_INFINITY
,
then fastly.error
will be set to EDOM
.
Example
declare local var.fo FLOAT;
set var.fo = math.acosh(10);