code: public static Atan2 atan2_x(Number xval) {
  		JcNumber sub = new JcNumber(xval, null, null);
  		return new Atan2(sub);
  	}
docs: <div color='red' style="font-size:24px;color:red"><b><i><u>JCYPHER</u></i></b></div>
  <div color='red' style="font-size:18px;color:red"><i>return the arctangent2 of a set of coordinates (x, y), in radians;</i></div>
  <div color='red' style="font-size:18px;color:red"><i>specify the x coordinate</i></div>
  <br/>