DoubleSummaryStatistics streamStats = stream(array).summaryStatistics();
      assertThat(stats.count()).isEqualTo(streamStats.getCount());
      assertEquivalent(stats.mean(), streamStats.getAverage());
      assertEquivalent(stats.sum(), streamStats.getSum());
      assertEquivalent(stats.max(), streamStats.getMax());
      assertEquivalent(stats.min(), streamStats.getMin());
    }
  }