@ScalarFunction(nullableParameters = true)
  public static byte[] toHLL(@Nullable Object input) {
    return toHLL(input, CommonConstants.Helix.DEFAULT_HYPERLOGLOG_LOG2M);
  }
@Test
  public void hllCreation() {
    for (Object i : _inputs) {
      Assert.assertEquals(hllEstimate(SketchFunctions.toHLL(i)), 1);
      Assert.assertEquals(hllEstimate(SketchFunctions.toHLL(i, 8)), 1);
    }
    Assert.assertEquals(hllEstimate(SketchFunctions.toHLL(null)), 0);
    Assert.assertEquals(hllEstimate(SketchFunctions.toHLL(null, 8)), 0);
  }