arctan

Definition: atom x2 = arctan(atom x1)
Description: Return an angle with tangent equal to x1.
Comments: A value between -PI/2 and PI/2 (radians) will be returned.

This function may be applied to an atom or sq_arctan() to all elements of a sequence. The rules for sequence operations apply.

arctan() is faster than arcsin() or arccos().
Example:
s = arctan(2)
-- s is 1.10715
See Also: tan, arcsin, arccos