@Test
  public void testSqrtAsDouble() {
    Decimal128 val1 = new Decimal128("1.00435134913958923485982394892384",
        (short) 36);
    Decimal128 val2 = new Decimal128("1.00345982739817298323423423", (short) 36);
    assertEquals(1.00217331292526d, val1.sqrtAsDouble(), 0.000000000000001d);
    assertEquals(1.00172841998127d, val2.sqrtAsDouble(), 0.000000000000001d);

  }
During earlier code testing, if we found errors, test them here as regression tests.
common/src/test/org/apache/hadoop/hive/common/type/TestDecimal128.java