assertThat(dataset).usingExactEquality().containsExactlyElementsIn(SIXTEEN_SQUARES_DOUBLES);
  }

  public void testQuartiles_index_compute_doubleCollection() {
    assertThat(quartiles().index(1).compute(SIXTEEN_SQUARES_DOUBLES))
        .isWithin(ALLOWED_ERROR)
        .of(SIXTEEN_SQUARES_QUARTILE_1);
  }