datafu-pig/src/main/java/datafu/pig/stats/IntVAR.java [116:204]:
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                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);
            }
                
        }
    }

    static public class Intermediate extends EvalFunc<Tuple> {
        @Override
        public Tuple exec(Tuple input) throws IOException {
            try {
                DataBag b = (DataBag)input.get(0);
                return combine(b);
            } catch (ExecException ee) {
                throw ee;
            } catch (Exception e) {
                int errCode = 2106;
                String msg = "Error while computing variacne in " + this.getClass().getSimpleName();
                throw new ExecException(msg, errCode, PigException.BUG, e);
            }
        }
    }

    static public class Final extends EvalFunc<Double> {
        @Override
        public Double exec(Tuple input) throws IOException {
            try {
                DataBag b = (DataBag)input.get(0);
                Tuple combined = combine(b);

                Long sum = (Long)combined.get(0);
                Long sumSquare = (Long)combined.get(1);
                if(sum == null) {
                    return null;
                }
                Long count = (Long)combined.get(2);

                Double var = null;
                
                if (count > 0) {
                    Double avg = new Double((double)sum / count);
                    Double avgSquare = new Double((double)sumSquare / count);
                    var = avgSquare - avg*avg;
                }
                return var;
            } catch (ExecException ee) {
                throw ee;
            } catch (Exception e) {
                int errCode = 2106;
                String msg = "Error while computing variance in " + this.getClass().getSimpleName();
                throw new ExecException(msg, errCode, PigException.BUG, e);
            }
        }
    }

    static protected Tuple combine(DataBag values) throws ExecException{
        long sum = 0;
        long sumSquare = 0;
        long totalCount = 0;

        // combine is called from Intermediate and Final
        // In either case, Initial would have been called
        // before and would have sent in valid tuples
        // Hence we don't need to check if incoming bag
        // is empty

        Tuple output = mTupleFactory.newTuple(3);
        boolean sawNonNull = false;
        for (Iterator<Tuple> it = values.iterator(); it.hasNext();) {
            Tuple t = it.next();
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datafu-pig/src/main/java/datafu/pig/stats/LongVAR.java [116:205]:
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                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);
            }
                
        }
    }

    static public class Intermediate extends EvalFunc<Tuple> {
        @Override
        public Tuple exec(Tuple input) throws IOException {
            try {
                DataBag b = (DataBag)input.get(0);
                return combine(b);
            } catch (ExecException ee) {
                throw ee;
            } catch (Exception e) {
                int errCode = 2106;
                String msg = "Error while computing variacne in " + this.getClass().getSimpleName();
                throw new ExecException(msg, errCode, PigException.BUG, e);
            
            }
        }
    }

    static public class Final extends EvalFunc<Double> {
        @Override
        public Double exec(Tuple input) throws IOException {
            try {
                DataBag b = (DataBag)input.get(0);
                Tuple combined = combine(b);

                Long sum = (Long)combined.get(0);
                Long sumSquare = (Long)combined.get(1);
                if(sum == null) {
                    return null;
                }
                Long count = (Long)combined.get(2);

                Double var = null;
                
                if (count > 0) {
                    Double avg = new Double((double)sum / count);
                    Double avgSquare = new Double((double)sumSquare / count);
                    var = avgSquare - avg*avg;
                }
                return var;
            } catch (ExecException ee) {
                throw ee;
            } catch (Exception e) {
                int errCode = 2106;
                String msg = "Error while computing variance in " + this.getClass().getSimpleName();
                throw new ExecException(msg, errCode, PigException.BUG, e);
            }
        }
    }

    static protected Tuple combine(DataBag values) throws ExecException{
        long sum = 0;
        long sumSquare = 0;
        long totalCount = 0;

        // combine is called from Intermediate and Final
        // In either case, Initial would have been called
        // before and would have sent in valid tuples
        // Hence we don't need to check if incoming bag
        // is empty

        Tuple output = mTupleFactory.newTuple(3);
        boolean sawNonNull = false;
        for (Iterator<Tuple> it = values.iterator(); it.hasNext();) {
            Tuple t = it.next();
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