@Udf(description = "Returns the inverse (arc) tangent of an INT value")
  public Double atan(
          @UdfParameter(
                  value = "value",
                  description = "The value to get the inverse tangent of."
          ) final Integer value
  ) {
    return atan(value == null ? null : value.doubleValue());
  }
@Test
  public void shouldHandleNull() {
    assertThat(udf.atan((Integer) null), is(nullValue()));
    assertThat(udf.atan((Long) null), is(nullValue()));
    assertThat(udf.atan((Double) null), is(nullValue()));
  }