private double sin(double angle){
  while (angle >= 180.0d) {
    angle-=180.0d;
  }
  double value=(angle / 180.0d * Math.PI);
  return Math.sin(value);
}

private double sin ( double angle ) { while ( angle >= 180.0d ) { angle -= 180.0d ; } double value = ( angle / 180.0d * Math . PI ) ; return Math . sin ( value ) ; }
gets the sinus of the angle .
