@Test
public void shouldGetAverageAndSum()
{
IQuery<WeatherObservation> query = new IterableQuery<>(SampleDataRepository.weatherObservations(), WeatherObservation.class);
double actualSum = 43.6 + 44.6 + 45.6 + 46.6 + 47.6 + 100.6;
assertThat(query.sum(new DoubleField("temp"))).isEqualTo(actualSum);
assertThat(query.average(new DoubleField("temp"))).isEqualTo(actualSum / 6);
}