Syntax
radianAngle = atn( expr )
Description
Returns the arctangent of expr in radians. In other words, if expr represents the tangent of some angle, then atn(expr) returns the angle. The returned angle will be in the range of -π/2 to +π/2 radians (which corresponds to -90 to +90 degrees). atn returns a double-precision result.
See also
sin; cos; tan; asin; acos; atan
