public static Subject[] findNatScSubjects(Data myData)  {
        List<Subject> results = new ArrayList<>();
        for(Subject thisWahlfach:myData.getWahlfaecher())   {
            if(thisWahlfach.getSubjectType()==NATURAL_SCIENCE) results.add(thisWahlfach);
        }
        if(results.isEmpty())   throw new NoSuchElementException();
        Subject[] resultsArr = new Subject[results.size()];
        resultsArr = results.toArray(resultsArr);
        return resultsArr;
    }