def test_conversion_factor_to(self):
        #conversion_factor_to should errror for units with different base power, should error for units with incompativle offset
        
        w = units.PhysicalQuantity('1cm')
        x = units.PhysicalQuantity('1m')
        y = units.PhysicalQuantity('1degF')
        z1 = units.PhysicalQuantity('1degC')
        z2 = units.PhysicalQuantity('1degK')
        
        self.assertEqual(w.unit.conversion_factor_to(x.unit),100.0/1)
        try: #incompatible units
            w.unit.conversion_factor_to(y.unit)
        except TypeError,err:
            self.assertEqual(str(err),"Incompatible units")
        else:
            self.fail("Expecting TypeError")
        #compatible offset units    
        self.assertEqual(z1.unit.conversion_factor_to(z2.unit),1.0)  
        try: #incompatible offset units
            y.unit.conversion_factor_to(z2.unit)
        except TypeError,err:
            self.assertEqual(str(err),"Unit conversion (degF to degK) cannot be expressed as a simple multiplicative factor")
        else:
            self.fail("Expecting TypeError")
dataset/ETHPy150Open OpenMDAO/OpenMDAO-Framework/openmdao.units/openmdao/units/test/test_units.py/test__PhysicalUnit.test_conversion_factor_to/swapped operands of `/`