The arctan function

Description

The arctan function returns the arctangent in radians of the parameter passed to it. So if X is the parameter passed to this function, then the value returned by this function Y is the angle in radians satisfying the following equation:

X = tan(Y)

The type of the value returned by this function is always real.

Parameter

The arctan function's only parameter is a numeric expression (i.e. an expression of integral type or of real type).

Example

   arctan(0.5) returns 4.64E-1

Portability

Operating Systems: All
Standard Pascal: Yes