code: private List<Double> getAngles() {
  		int n = subunits.getSubunitCount();
  		// for spherical symmetric cases, n cannot be higher than 60
  		if (n % 60 == 0 && isSpherical()) {
  			 n = 60;
  		}
  		List<Integer> folds = subunits.getFolds();
  		List<Double> angles = new ArrayList<Double>(folds.size()-1);
  
  		// note this loop starts at 1, we do ignore 1-fold symmetry, which is the first entry
  		for (int fold: folds) {
  			if (fold > 0 && fold <= n) {
  				angles.add(2* Math.PI/fold);
  			}
  		}
  		return angles;
  	}
docs: Get valid rotation angles given the number of subunits
  @return The rotation angle corresponding to each fold of {@link Subunits#getFolds()}