public static Combine.BinaryCombineDoubleFn ofDoubles() {
    return new Max.MaxDoubleFn();
  }
@Test
  public void testMaxDoubleFnNan() {
    testCombineFn(
        Max.ofDoubles(),
        Lists.newArrayList(Double.NaN, 2.0, 3.0, Double.POSITIVE_INFINITY),
        Double.NaN);
  }