@Override
    public String toString() {
        return getClass().getSimpleName() + " barCount: " + barCount;
    }
@Test
    public void onlyNaNValues() {
        BaseBarSeries series = new BaseBarSeries("NaN test");
        for (long i = 0; i <= 1000; i++) {
            series.addBar(ZonedDateTime.now().plusDays(i), NaN, NaN, NaN, NaN, NaN);
        }

        AroonUpIndicator aroonUpIndicator = new AroonUpIndicator(series, 5);
        for (int i = series.getBeginIndex(); i <= series.getEndIndex(); i++) {
            assertEquals(NaN.toString(), aroonUpIndicator.getValue(i).toString());
        }
    }