RTOD()
 Converts from a radian to degree measure
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 Syntax

     RTOD(<nArc>) --> nAngle

 Argument

     <nArc>  Designates a valid angle measurement in radians.

 Returns

     RTOD() returns the value of the designated parameter in degrees.

 Description

     In addition to expressing an angle measurement in degrees, it is often
     useful to express an angle in radians.  RTOD() converts a radian
     measurement into degrees.

 Example

     Show some conversions:

     ? RTOD( PI() )        // Result:  180
     ? RTOD(2 * PI())      // Result:  360
     ? RTOD(4 * PI())      // Result:  720
     ? RTOD( -PI() )       // Result: -180