atan method
Arctangent
Compute the inverse tangent of this complex number.
Implements the formula:
atan(z) = (i/2) log((i + z)/(i - z))
Returns nan
if either real or imaginary part of the
input argument is NaN
or infinite.
Implementation
Complex atan() {
if (isNaN) return Complex.nan;
return ((this + Complex.i) / (Complex.i - this)).log() * 0.5.imag;
}