acos function

Input type	Output type
float complex	float complex

This function calculates the arccosine of the argument and returns the result. If the argument is of type int, it is first converted to float by the compiler.

Examples:

acos(0)      ; 1.5708
acos(0.0)    ; 1.5708
acos((0,0))  ; (1.5708, 0)

Notes

acos(cos(x)) is equal to x if x is within the range -pi..pi.
The argument should not be outside the range -1..1. Otherwise this function will return an invalid value. See Invalid operations.