code: public static BigComplex atan(BigComplex x, MathContext mathContext) {
  		MathContext mc = new MathContext(mathContext.getPrecision() + 4, mathContext.getRoundingMode());
  
  		return log(I.subtract(x, mc).divide(I.add(x, mc), mc), mc).divide(I, mc).divide(TWO, mc).round(mathContext);
  	}
docs: Calculates the arc tangens (inverted tangens) of {@link BigComplex} x in the complex domain.
  
  <p>See: <a href="https://en.wikipedia.org/wiki/Inverse_trigonometric_functions#Extension_to_complex_plane">Wikipedia: Inverse trigonometric functions (Extension to complex plane)</a></p>
  
  @param x the {@link BigComplex} to calculate the arc tangens for
  @param mathContext the {@link MathContext} used for the result
  @return the calculated arc tangens {@link BigComplex} with the precision specified in the <code>mathContext</code>