@Test
public void testClear() {

  DoubleColumn doubles = DoubleColumn.create("doubles", 100);
  for (int i = 0; i < 100; i++) {
    doubles.set(i, RandomUtils.nextDouble(0, 10_000));
  }
  assertFalse(doubles.isEmpty());
  doubles.clear();
  assertTrue(doubles.isEmpty());
}