Name:
acos() -- returns the arcus cosine of its numeric argument
Synopsis:
x=acos(angle)
Description:
The acos is the arcus cosine-function, i.e. the inverse of the cos-function. Or, more elaborate: It Returns the angle (in radian, not degree!), which, fed to the cosine-function will produce the argument passed to the acos-function.
Example:
print acos(0.5),acos(cos(pi))
Explanation:
This example will print 1.0472 3.14159 which are pi/3 and pi respectively.
Related: cos, asin