Method exec

tutorial/src/org/apache/pig/tutorial/ScoreGenerator.java:75–115

(Tuple input)

    }

    public DataBag exec(Tuple input) throws IOException {
        if (input == null || input.size() == 0)
            return null;
        try{
            DataBag output = DefaultBagFactory.getInstance().newDefaultBag();
            DataBag in = (DataBag)input.get(0);
    
            Map<String, Long> pairs = new HashMap<String, Long>();
            List<Long> counts = new ArrayList<Long> ();

            Iterator<Tuple> it = in.iterator();
            while (it.hasNext()) {
                Tuple t = it.next();
                String hour = (String)t.get(1);
                Long count = (Long)t.get(2);
                pairs.put(hour, count);
                counts.add(count);
            }
    
            double mean = computeMean(counts);
            double standardDeviation = computeSD(counts, mean);

            Iterator<String> it2 = pairs.keySet().iterator();
            while (it2.hasNext()) {
                String hour = it2.next();
                Long count = pairs.get(hour);
                if ( count > mean ) {
                    Tuple t = TupleFactory.getInstance().newTuple(4);
                    t.set(0, hour);
                    t.set(1, ((double) count - mean) / standardDeviation ); // the score
                    t.set(2, count);
                    t.set(3, mean);
                    output.add(t);
                }
            }
            return output;
        }catch (Exception e){
            System.err.println("ScoreGenerator: failed to process input; error - " + e.getMessage());
            return null;
        }
    }

    @Override
    /**