@Udf(description = "Returns the base 10 logarithm of an INT value.")
  public Double log(
          @UdfParameter(
                  value = "value",
                  description = "the value get the base 10 logarithm of."
          ) final Integer value
  ) {
    return log(value == null ? null : value.doubleValue());
  }
@Test
  public void shouldHandleNegativeValue() {
    assertThat(Double.isNaN(udf.log(-1)), is(true));
    assertThat(Double.isNaN(udf.log(-1L)), is(true));
    assertThat(Double.isNaN(udf.log(-1.0)), is(true));
    assertThat(Double.isNaN(udf.log(15, -1)), is(true));
    assertThat(Double.isNaN(udf.log(15L, -1L)), is(true));
    assertThat(Double.isNaN(udf.log(15.0, -1.0)), is(true));
  }