public Tuple exec()

in datafu-pig/src/main/java/datafu/pig/stats/VAR.java [104:156]
46 lines of code
9 McCabe index (conditional complexity)

        public Tuple exec(Tuple input) throws IOException {
            Tuple t = mTupleFactory.newTuple(3);
            try {
                // input is a bag with one tuple containing
                // the column we are trying to get variance 
                DataBag bg = (DataBag) input.get(0);
                DataByteArray dba = null;
                Iterator<Tuple> iter = bg.iterator();
                if(iter.hasNext()) {
                    Tuple tp = iter.next();
                    dba = (DataByteArray)tp.get(0);
                }
                
                if (iter.hasNext())
                {
                  throw new RuntimeException("Expected only one tuple in bag");
                }
                
                Double d = dba !=null ? Double.valueOf(dba.toString()) : null;
                if (dba == null){
                    t.set(0, null);
                    t.set(1, null);
                    t.set(2, 0L);
                }
                else {
                    t.set(0, d);
                    t.set(1, d*d);
                    t.set(2, 1L);
                }
                return t;
            } catch(NumberFormatException nfe) {
                nfe.printStackTrace();
                // invalid input,
                // treat this input as null
                try {
                    t.set(0, null);
                    t.set(1, null);
                    t.set(2, 0L);
                } catch (ExecException e) {
                    throw e;
                }
                return t;
            } catch (ExecException ee) {
                ee.printStackTrace();
                throw ee;
            } catch (Exception e) {
                e.printStackTrace();
                int errCode = 2106;
                String msg = "Error while computing variance in " + this.getClass().getSimpleName();
                throw new ExecException(msg, errCode, PigException.BUG, e);
            }
                
        }