public void testNegate() {
DecimalColumnVector dcv = new DecimalColumnVector(4 ,20, 13);
HiveDecimal d1 = HiveDecimal.create("19.56778");
HiveDecimal expected1 = HiveDecimal.create("-19.56778");
DecimalUtil.negate(0, d1, dcv);
Assert.assertEquals(0, expected1.compareTo(dcv.vector[0].getHiveDecimal()));
HiveDecimal d2 = HiveDecimal.create("-25.34567");
HiveDecimal expected2 = HiveDecimal.create("25.34567");
DecimalUtil.negate(0, d2, dcv);
Assert.assertEquals(0, expected2.compareTo(dcv.vector[0].getHiveDecimal()));