@Test public void testDifference() { int[] originalValues = new int[] {32, 42, 40, 57, 52}; int[] expectedValues = new int[] {IntColumn.MISSING_VALUE, 10, -2, 17, -5}; IntColumn initial = new IntColumn("Test", originalValues.length); for (int value : originalValues) { initial.add(value); } IntColumn difference = initial.difference(); assertEquals( "Both sets of data should be the same size.", expectedValues.length, difference.size()); for (int index = 0; index < difference.size(); index++) { int actual = difference.get(index); assertEquals( "difference operation at index:" + index + " failed", expectedValues[index], actual); } }