Python CreateFDM.load_script方法代码示例

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def testFunctionWithIndexedProps(self):
        tree = et.parse(self.sandbox.path_to_jsbsim_file('engine',
                                                         'eng_PegasusXc.xml'))
        # Define the function starter-max-power-W as a 'post' function
        root = tree.getroot()
        startPowFunc_tag = root.find("function/[@name='propulsion/engine[#]/starter-max-power-W']")
        startPowFunc_tag.attrib['type']='post'
        tree.write('eng_PegasusXc.xml')

        # Copy the propeller file.
        shutil.copy(self.sandbox.path_to_jsbsim_file('engine', 'prop_deHavilland5000.xml'),
                    '.')
        fdm = CreateFDM(self.sandbox)
        fdm.set_engine_path('.')
        fdm.load_script(self.sandbox.path_to_jsbsim_file('scripts',
                                                         'Short_S23_1.xml'))
        fdm.run_ic()
        pm = fdm.get_property_manager()
        self.assertTrue(pm.hasNode('propulsion/engine[0]/starter-max-power-W'))
        self.assertTrue(pm.hasNode('propulsion/engine[1]/starter-max-power-W'))
        self.assertTrue(pm.hasNode('propulsion/engine[2]/starter-max-power-W'))
        self.assertTrue(pm.hasNode('propulsion/engine[3]/starter-max-power-W'))

        while fdm.run():
            rpm = [fdm['propulsion/engine[0]/engine-rpm'],
                   fdm['propulsion/engine[1]/engine-rpm'],
                   fdm['propulsion/engine[2]/engine-rpm'],
                   fdm['propulsion/engine[3]/engine-rpm']]
            for i in range(4):
                maxPower = max(0.0, 1.0-rpm[i]/400)*498.941*0.10471976*rpm[i]
                self.assertAlmostEqual(fdm['propulsion/engine[%d]/starter-max-power-W' % (i,)],
                                       maxPower)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def testOrbit(self):
        script_name = 'ball_orbit.xml'
        script_path = self.sandbox.path_to_jsbsim_file('scripts', script_name)
        self.AddAccelerometersToAircraft(script_path)

        # The time step is too small in ball_orbit so let's increase it to 0.1s
        # for a quicker run
        tree = et.parse(script_path)
        run_tag = tree.getroot().find('./run')
        run_tag.attrib['dt'] = '0.1'
        tree.write(script_name)

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_name)
        # Switch the accel on
        fdm['fcs/accelerometer/on'] = 1.0
        fdm.run_ic()

        while fdm.run():
            self.assertAlmostEqual(fdm['fcs/accelerometer/X'], 0.0, delta=1E-8)
            self.assertAlmostEqual(fdm['fcs/accelerometer/Y'], 0.0, delta=1E-8)
            self.assertAlmostEqual(fdm['fcs/accelerometer/Z'], 0.0, delta=1E-8)
            self.assertAlmostEqual(fdm['accelerations/a-pilot-x-ft_sec2'], 0.0,
                                   delta=1E-8)
            self.assertAlmostEqual(fdm['accelerations/a-pilot-y-ft_sec2'], 0.0,
                                   delta=1E-8)
            self.assertAlmostEqual(fdm['accelerations/a-pilot-z-ft_sec2'], 0.0,
                                   delta=1E-8)

        del fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def test_fuel_tanks_content(self):
        script_path = self.sandbox.path_to_jsbsim_file('scripts', 'J2460.xml')
        fdm = CreateFDM(self.sandbox)
        fdm.load_script(script_path)
        fdm.run_ic()

        tree = et.parse(script_path)
        use_tag = tree.getroot().find('use')
        aircraft_name = use_tag.attrib['aircraft']
        aircraft_path = self.sandbox.path_to_jsbsim_file('aircraft',
                                                         aircraft_name)
        aircraft_tree = et.parse(os.path.join(aircraft_path,
                                              aircraft_name+'.xml'))

        total_fuel_quantity = 0.0
        total_oxidizer_quantity = 0.0
        for tank in aircraft_tree.findall('propulsion/tank'):
            contents = float(tank.find('contents').text)
            if tank.attrib['type'] == "FUEL":
                total_fuel_quantity += contents
            elif tank.attrib['type'] == 'OXIDIZER':
                total_oxidizer_quantity += contents

        self.assertAlmostEqual(fdm['propulsion/total-fuel-lbs'],
                               total_fuel_quantity)

        self.assertAlmostEqual(fdm['propulsion/total-oxidizer-lbs'],
                               total_oxidizer_quantity)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def Compare(self, section):
        # Rerun the script with the modified aircraft definition
        self.sandbox.delete_csv_files()
        fdm = CreateFDM(self.sandbox)
        # We need to tell JSBSim that the aircraft definition is located in the
        # directory build/.../aircraft
        fdm.set_aircraft_path('aircraft')
        fdm.set_output_directive(self.sandbox.path_to_jsbsim_file('tests',
                                                                  'output.xml'))
        fdm.load_script(self.script)
        fdm['simulation/randomseed'] = 0.0

        fdm.run_ic()
        ExecuteUntil(fdm, 50.0)

        mod = pd.read_csv('output.csv', index_col=0)

        # Check the data are matching i.e. the time steps are the same between
        # the two data sets and that the output data are also the same.
        self.assertTrue(isDataMatching(self.ref, mod))

        # Whether the data is read from the aircraft definition file or from an
        # external file, the results shall be exactly identical. Hence the
        # precision set to 0.0.
        diff = FindDifferences(self.ref, mod, 0.0)
        self.assertEqual(len(diff), 0,
                         msg='\nTesting section "'+section+'"\n'+diff.to_string())

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def test_gust_reset(self):
        fdm = CreateFDM(self.sandbox)
        fdm.load_script(self.sandbox.path_to_jsbsim_file('scripts',
                                                         'c172_cruise_8K.xml'))
        fdm['simulation/randomseed'] = 0.0
        fdm.set_output_directive(self.sandbox.path_to_jsbsim_file('tests', 'output.xml'))

        fdm.run_ic()
        ExecuteUntil(fdm, 15.5)

        ref = pd.read_csv('output.csv', index_col=0)

        fdm['simulation/randomseed'] = 0.0
        fdm.reset_to_initial_conditions(1)
        ExecuteUntil(fdm, 15.5)

        current = pd.read_csv('output_0.csv', index_col=0)

        # Check the data are matching i.e. the time steps are the same between
        # the two data sets and that the output data are also the same.
        self.assertTrue(isDataMatching(ref, current))

        # Find all the data that are differing by more than 1E-8 between the
        # two data sets.
        diff = FindDifferences(ref, current, 1E-8)
        self.longMessage = True
        self.assertEqual(len(diff), 0, msg='\n'+diff.to_string())

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def test_wind_frame(self):
        script_path = self.sandbox.path_to_jsbsim_file('scripts',
                                                       'ball_chute.xml')
        fdm = CreateFDM(self.sandbox)

        fdm.load_script(script_path)
        fdm.run_ic()

        self.assertAlmostEqual(fdm['external_reactions/parachute/location-x-in'],
                               12.0)
        self.assertAlmostEqual(fdm['external_reactions/parachute/location-y-in'],
                               0.0)
        self.assertAlmostEqual(fdm['external_reactions/parachute/location-z-in'],
                               0.0)
        self.assertAlmostEqual(fdm['external_reactions/parachute/x'], -1.0)
        self.assertAlmostEqual(fdm['external_reactions/parachute/y'], 0.0)
        self.assertAlmostEqual(fdm['external_reactions/parachute/z'], 0.0)

        while fdm.run():
            Tw2b = fdm.get_auxiliary().get_Tw2b()
            mag = fdm['aero/qbar-psf'] * fdm['fcs/parachute_reef_pos_norm']*20.0
            f = Tw2b * np.mat([-1.0, 0.0, 0.0]).T * mag
            self.assertAlmostEqual(fdm['forces/fbx-external-lbs'], f[0, 0])
            self.assertAlmostEqual(fdm['forces/fby-external-lbs'], f[1, 0])
            self.assertAlmostEqual(fdm['forces/fbz-external-lbs'], f[2, 0])

            m = np.cross(self.getLeverArm(fdm,'parachute'),
                         np.array([f[0,0], f[1,0], f[2, 0]]))
            self.assertAlmostEqual(fdm['moments/l-external-lbsft'], m[0])
            self.assertAlmostEqual(fdm['moments/m-external-lbsft'], m[1])
            self.assertAlmostEqual(fdm['moments/n-external-lbsft'], m[2])

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def testDebugLvl(self):
        fdm = CreateFDM(self.sandbox)
        fdm.load_script(self.sandbox.path_to_jsbsim_file('scripts',
                                                         'ball_orbit.xml'))
        fdm.run_ic()

        ExecuteUntil(fdm, 1000.)

        ref = pd.read_csv('BallOut.csv', index_col=0)
        del fdm

        os.environ["JSBSIM_DEBUG"] = str(0)
        fdm = CreateFDM(self.sandbox)
        fdm.load_script(self.sandbox.path_to_jsbsim_file('scripts',
                                                         'ball_orbit.xml'))
        fdm.run_ic()

        ExecuteUntil(fdm, 1000.)

        current = pd.read_csv('BallOut.csv', index_col=0)

        # Check the data are matching i.e. the time steps are the same between
        # the two data sets and that the output data are also the same.
        self.assertTrue(isDataMatching(ref, current))

        # Find all the data that are differing by more than 1E-8 between the
        # two data sets.
        diff = FindDifferences(ref, current, 1E-8)
        self.longMessage = True
        self.assertEqual(len(diff), 0, msg='\n'+diff.to_string())

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def test_hold_down_with_gnd_reactions(self):
        fdm = CreateFDM(self.sandbox)
        fdm.load_script(self.sandbox.path_to_jsbsim_file('scripts',
                                                         'c1721.xml'))
        fdm.run_ic()
        ExecuteUntil(fdm, 0.25)

        fdm['forces/hold-down'] = 1.0
        h0 = fdm['position/h-sl-ft']
        pitch = fdm['attitude/pitch-rad']
        roll = fdm['attitude/roll-rad']
        heading = fdm['attitude/heading-true-rad']

        while fdm['simulation/sim-time-sec'] < 2.0:
            fdm.run()
            self.assertAlmostEqual(fdm['accelerations/pdot-rad_sec2'], 0.0)
            self.assertAlmostEqual(fdm['accelerations/qdot-rad_sec2'], 0.0)
            self.assertAlmostEqual(fdm['accelerations/rdot-rad_sec2'], 0.0)
            self.assertAlmostEqual(fdm['accelerations/udot-ft_sec2'], 0.0)
            self.assertAlmostEqual(fdm['accelerations/vdot-ft_sec2'], 0.0)
            self.assertAlmostEqual(fdm['accelerations/wdot-ft_sec2'], 0.0)

        self.assertAlmostEqual(fdm['position/h-sl-ft'], h0, delta=1E-6)
        self.assertAlmostEqual(fdm['attitude/pitch-rad'], pitch)
        self.assertAlmostEqual(fdm['attitude/roll-rad'], roll)
        self.assertAlmostEqual(fdm['attitude/heading-true-rad'], heading)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def test_output(self):
        tree = et.parse(self.script_path)
        output_tag = et.SubElement(tree.getroot(), 'output')
        output_tag.attrib['name'] = 'test.csv'
        output_tag.attrib['type'] = 'CSV'
        output_tag.attrib['rate'] = '10'
        property_tag = et.SubElement(output_tag, 'property')
        property_tag.text = 'position/vrp-radius-ft'
        tree.write('c1722_0.xml')

        fdm = CreateFDM(self.sandbox)
        fdm.load_script('c1722_0.xml')
        fdm.run_ic()
        ExecuteUntil(fdm, 10.)

        self.assertTrue(self.sandbox.exists(output_tag.attrib['name']),
                        msg="The file 'output.csv' has not been created")
        orig = pd.read_csv('JSBout172B.csv', index_col=0)
        test = pd.read_csv('test.csv', index_col=0)
        pname = '/fdm/jsbsim/' + property_tag.text
        ref = orig[pname]
        mod = test[pname]

        # Check the data are matching i.e. the time steps are the same between
        # the two data sets.
        self.assertTrue(isDataMatching(ref, mod))

        # Find all the data that are differing by more than 1E-8 between the
        # two data sets.
        delta = pd.concat([np.abs(ref - mod), ref, mod], axis=1)
        delta.columns = ['delta', 'ref value', 'value']
        diff = delta[delta['delta'] > 1E-8]
        self.longMessage = True
        self.assertEqual(len(diff), 0, msg='\n'+diff.to_string())

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def test_CAS_ic(self):
        script_name = 'Short_S23_3.xml'
        script_path = self.sandbox.path_to_jsbsim_file('scripts', script_name)

        # Add a Pitot angle to the Short S23
        tree, aircraft_name, path_to_jsbsim_aircrafts = CopyAircraftDef(script_path, self.sandbox)
        self.addPitotTube(tree.getroot(), 5.0)
        tree.write(self.sandbox('aircraft', aircraft_name,
                                aircraft_name+'.xml'))

        # Read the CAS specified in the IC file
        tree = et.parse(script_path)
        use_element = tree.getroot().find('use')
        IC_file = use_element.attrib['initialize']
        tree = et.parse(os.path.join(path_to_jsbsim_aircrafts,
                                     append_xml(IC_file)))
        vc_tag = tree.getroot().find('./vc')
        VCAS = float(vc_tag.text)
        if 'unit' in vc_tag.attrib and vc_tag.attrib['unit'] == 'FT/SEC':
            VCAS /= 1.68781  # Converts in kts

        # Run the IC and check that the model is initialized correctly
        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        fdm.run_ic()

        self.assertAlmostEqual(fdm['ic/vc-kts'], VCAS, delta=1E-7)
        self.assertAlmostEqual(fdm['velocities/vc-kts'], VCAS, delta=1E-7)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def test_fuel_tanks_inertia(self):
        script_path = self.sandbox.path_to_jsbsim_file('scripts', 'c1722.xml')

        # The aircraft c172x does not contain an <inertia_factor> tag so we
        # need to add one.
        tree, aircraft_name, b = CopyAircraftDef(script_path, self.sandbox)
        tank_tag = tree.getroot().find('propulsion/tank')
        inertia_factor = et.SubElement(tank_tag, 'inertia_factor')
        inertia_factor.text = '1.0'
        tree.write(self.sandbox('aircraft', aircraft_name,
                                aircraft_name+'.xml'))

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        fdm.run_ic()

        contents0 = fdm['propulsion/tank/contents-lbs']
        ixx0 = fdm['propulsion/tank/local-ixx-slug_ft2']
        iyy0 = fdm['propulsion/tank/local-iyy-slug_ft2']
        izz0 = fdm['propulsion/tank/local-izz-slug_ft2']

        # Remove half of the tank contents and check that the inertias are
        # updated accordingly
        fdm['propulsion/tank/contents-lbs'] = 0.5*contents0
        contents = fdm['propulsion/tank/contents-lbs']
        ixx = fdm['propulsion/tank/local-ixx-slug_ft2']
        iyy = fdm['propulsion/tank/local-iyy-slug_ft2']
        izz = fdm['propulsion/tank/local-izz-slug_ft2']

        self.assertAlmostEqual(contents, 0.5*contents0, delta=1E-7,
                               msg="The tank content (%f lbs) should be %f lbs" % (contents, 0.5*contents0))
        self.assertAlmostEqual(ixx, 0.5*ixx0, delta=1E-7,
                               msg="The tank inertia Ixx (%f slug*ft^2) should be %f slug*ft^2" % (ixx, 0.5*ixx0))
        self.assertAlmostEqual(iyy, 0.5*iyy0, delta=1E-7,
                               msg="The tank inertia Iyy (%f slug*ft^2) should be %f slug*ft^2" % (iyy, 0.5*iyy0))
        self.assertAlmostEqual(izz, 0.5*izz0, delta=1E-7,
                               msg="The tank inertia Izz (%f slug*ft^2) should be %f slug*ft^2" % (izz, 0.5*izz0))

        # Execute the script and check that the fuel inertias have been updated
        # along with the consumption.
        ExecuteUntil(fdm, 200.0)

        contents = fdm['propulsion/tank/contents-lbs']
        ixx = fdm['propulsion/tank/local-ixx-slug_ft2']
        iyy = fdm['propulsion/tank/local-iyy-slug_ft2']
        izz = fdm['propulsion/tank/local-izz-slug_ft2']

        contents_ratio = contents / contents0
        ixx_ratio = ixx / ixx0
        iyy_ratio = iyy / iyy0
        izz_ratio = izz / izz0

        self.assertAlmostEqual(contents_ratio, ixx_ratio, delta=1E-7,
                               msg="Ixx does not vary as the tank content does\nIxx ratio=%f\nContents ratio=%f" % (ixx_ratio, contents_ratio))
        self.assertAlmostEqual(contents_ratio, iyy_ratio, delta=1E-7,
                               msg="Iyy does not vary as the tank content does\nIyy ratio=%f\nContents ratio=%f" % (iyy_ratio, contents_ratio))
        self.assertAlmostEqual(contents_ratio, izz_ratio, delta=1E-7,
                               msg="Izz does not vary as the tank content does\nIzz ratio=%f\nContents ratio=%f" % (izz_ratio, contents_ratio))

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def test_no_input(self):
        fdm = CreateFDM(self.sandbox)
        fdm.load_script(self.script_path)
        fdm.run_ic()
        fdm.hold()

        with self.assertRaises(socket.error):
            TelnetInterface(fdm, 5., 1137)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def test_no_output(self):
        fdm = CreateFDM(self.sandbox)
        fdm.load_script(self.script_path)
        fdm.run_ic()
        ExecuteUntil(fdm, 10.)

        self.assertFalse(self.sandbox.exists('output.csv'),
                         msg="Results have unexpectedly been written to 'output.csv'")

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def testSteadyFlight(self):
        script_name = 'c1722.xml'
        script_path = self.sandbox.path_to_jsbsim_file('scripts', script_name)
        self.AddAccelerometersToAircraft(script_path)

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        # Switch the accel on
        fdm['fcs/accelerometer/on'] = 1.0
        # Use the standard gravity (i.e. GM/r^2)
        fdm['simulation/gravity-model'] = 0
        # Select an orientation such that frame transformations simplify
        fdm['ic/psi-true-rad'] = 0.0
        fdm.run_ic()

        ExecuteUntil(fdm, 0.1)

        fdm['simulation/do_simple_trim'] = 1

        r = fdm['position/radius-to-vehicle-ft']
        pitch = fdm['attitude/theta-rad']
        roll = fdm['attitude/phi-rad']
        latitude = fdm['position/lat-gc-rad']
        g = fdm['accelerations/gravity-ft_sec2']
        omega = 0.00007292115  # Earth rotation rate in rad/sec
        fc = r * math.cos(latitude) * omega * omega  # Centrifugal force

        uvw = np.array(fdm.get_propagate().get_uvw().T)[0]
        Omega = omega * np.array([math.cos(pitch - latitude),
                                  math.sin(pitch - latitude) * math.sin(roll),
                                  math.sin(pitch - latitude) * math.cos(roll)])

        # Compute the acceleration measured by the accelerometer as the sum of
        # the gravity and the centrifugal and Coriolis forces.
        fa_yz = (fc * math.cos(latitude - pitch) - g * math.cos(pitch))
        fa = np.array([(fc * math.sin(latitude - pitch) + g * math.sin(pitch)),
                       fa_yz * math.sin(roll),
                       fa_yz * math.cos(roll)]) + np.cross(2.0*Omega, uvw)

        # After the trim we are close to the equilibrium but there remains a
        # small residual that we have to take the bias into account
        fax = fa[0] + fdm['accelerations/udot-ft_sec2']
        fay = fa[1] + fdm['accelerations/vdot-ft_sec2']
        faz = fa[2] + fdm['accelerations/wdot-ft_sec2']

        # Deltas are relaxed because the tolerances of the trimming algorithm
        # are quite relaxed themselves.
        self.assertAlmostEqual(fdm['fcs/accelerometer/X'], fax, delta=1E-6)
        self.assertAlmostEqual(fdm['fcs/accelerometer/Y'], fay, delta=1E-4)
        self.assertAlmostEqual(fdm['fcs/accelerometer/Z'], faz, delta=1E-5)

        del fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import load_script [as 别名]
    def testEnginePowerVC(self):
        # Check that the same results are obtained whether the engine power
        # velocity correction is given in a <table> or <function>
        fdm = CreateFDM(self.sandbox)
        fdm.load_script(self.sandbox.path_to_jsbsim_file('scripts',
                                                         'L4102.xml'))
        fdm.run_ic()

        while fdm.run():
            pass

        del fdm

        ref = pd.read_csv('L410.csv', index_col=0)

        tree = et.parse(self.sandbox.path_to_jsbsim_file('engine',
                                                         'engtm601.xml'))
        # Modify the engine definition to use a <function> rather than a
        # <table> component.
        root = tree.getroot()
        engPowVC_tag = root.find("table/[@name='EnginePowerVC']")
        root.remove(engPowVC_tag)
        del engPowVC_tag.attrib['name']
        func_engPowVC = et.SubElement(root, 'function')
        func_engPowVC.attrib['name'] = 'EnginePowerVC'
        func_engPowVC.append(engPowVC_tag)
        tree.write('engtm601.xml')

        # Copy the propeller file.
        shutil.copy(self.sandbox.path_to_jsbsim_file('engine', 'vrtule2.xml'),
                    '.')
        self.sandbox.delete_csv_files()

        fdm = CreateFDM(self.sandbox)
        fdm.set_engine_path('.')
        fdm.load_script(self.sandbox.path_to_jsbsim_file('scripts',
                                                         'L4102.xml'))
        fdm.run_ic()

        while fdm.run():
            pass

        current = pd.read_csv('L410.csv', index_col=0)

        # Check the data are matching i.e. the time steps are the same between
        # the two data sets and that the output data are also the same.
        self.assertTrue(isDataMatching(ref, current))

        # Find all the data that are differing by more than 1E-5 between the
        # two data sets.
        diff = FindDifferences(ref, current, 0.0)
        self.longMessage = True
        self.assertEqual(len(diff), 0, msg='\n'+diff.to_string())