@Test
public void testDescriptor2() throws InvalidSmilesException {

    SmilesParser sp = new SmilesParser(DefaultChemObjectBuilder.getInstance());
    IAtomContainer mol1 = sp.parseSmiles("CO");
    double value = ((DoubleResult) descriptor.calculate(mol1.getBond(0), mol1).getValue()).doubleValue();
    Assert.assertEquals(2, value, 0.0000);
}