How to calculate `inverse tangent` from a given numeric value

[J.D.Holden]

I wish to know how to calculate the size of an angle, in degrees, by using
the inverse tangent of a given numeric value.
This is to be done using `formulas` in Excel in XP.
This is easy to calculate using the scientific calculator on the PC but
would appear to be an unavailable function in `formulas`, unless of course it
involves conversion to radians.
Any ideas will be most welcome.

 

[Jerry W. Lewis]

=DEGREES(ATAN(tangentValue))

Excel does trig in radians instead of degrees, but there are RADIANS()
and DEGREES() functions for conversions.

Jerry