Quantiles.Scale intermediate = Quantiles.scale(10);
    assertThrows(IllegalArgumentException.class, () -> intermediate.indexes(1, 11, 3));
  }

  public void testScale_indexes_collection_negative() {
    Quantiles.Scale intermediate = Quantiles.scale(10);
    assertThrows(
        IllegalArgumentException.class, () -> intermediate.indexes(ImmutableList.of(1, -1, 3)));
  }