@Test
    public void testTimeStep_MONTHLY_MEAN() throws Exception {
        printDebug("----------------------------");
        printDebug("Monthly Mean: " + this.toString());
        printDebug("----------------------------");
        CSTable t = DataIO.table(r, "obs");
        Assert.assertNotNull(t);

        // 4 YEARS
        Date start = Conversions.convert("1983-10-13", Date.class);
        Date end = Conversions.convert("1984-2-25", Date.class);

        //System.out.println("Start = " + start.toString() + "; End = " + end.toString());
        double[] mean = DataIO.getColumnDoubleValuesInterval(start, end, t, "runoff[0]", DataIO.MONTHLY_MEAN);

        double[] goldenMean = new double[5];
        goldenMean[0] = 3034 / 19.0; // for 10-1983
        goldenMean[1] = 15156 / 30.0; // 11-1983
        goldenMean[2] = 15773 / 31.0; // 12-1983
        goldenMean[3] = 10596 / 31.0; // 1-1984
        goldenMean[4] = 5993 / 25.0; // 2-1984
        for (int i = 0; i < mean.length; i++) {
            printDebug("MonthlyMean[" + i + "] = " + mean[i] + ";\tGolden MonthlyMean[" + i + "] = " + goldenMean[i]);

        }

        Assert.assertArrayEquals(goldenMean, mean, 0);
    }