Python CreateFDM.run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 run [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 run [as 别名]
    def test_direct_steer(self):
        fdm = CreateFDM(self.sandbox)
        fdm.load_model('c172r')
        aircraft_path = self.sandbox.path_to_jsbsim_file('aircraft')
        fdm.load_ic(os.path.join(aircraft_path, 'c172r', 'reset00'), False)
        fdm.run_ic()
        self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 0.0)
        self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 0.0)

        # Should be part of a unit test in C++ ?
        fpectl.turnon_sigfpe()

        grndreact = fdm.get_ground_reactions()
        for i in xrange(grndreact.get_num_gear_units()):
            gear = grndreact.get_gear_unit(i)
            self.assertEqual(gear.get_steer_norm(), 0.0)

        fpectl.turnoff_sigfpe()

        fdm['fcs/steer-pos-deg'] = 5.0
        self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 5.0)
        fdm.run()
        self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 0.0)
        fdm['fcs/steer-cmd-norm'] = 1.0
        self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 1.0)
        fdm.run()
        self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 1.0)
        self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 10.0)

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

        # Add a Pitot angle to the Cessna 172
        tree, aircraft_name, path_to_jsbsim_aircrafts = CopyAircraftDef(script_path, self.sandbox)
        root = tree.getroot()
        pitot_angle_deg = 5.0
        self.addPitotTube(root, 5.0)
        contact_tag = root.find('./ground_reactions/contact')
        contact_tag.attrib['type'] = 'STRUCTURE'
        tree.write(self.sandbox('aircraft', aircraft_name,
                                aircraft_name+'.xml'))

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_model('ball')
        pitot_angle = pitot_angle_deg * math.pi / 180.
        weight = fdm['inertia/weight-lbs']
        spring_tag = contact_tag.find('./spring_coeff')
        spring_coeff = float(spring_tag.text)
        print "Weight=%d Spring=%d" % (weight, spring_coeff)
        fdm['ic/h-sl-ft'] = weight / spring_coeff
        fdm['forces/hold-down'] = 1.0
        fdm.run_ic()

        ExecuteUntil(fdm, 10.)

        for i in xrange(36):
            for j in xrange(-9, 10):
                angle = math.pi * i / 18.0
                angle2 = math.pi * j / 18.0
                ca2 = math.cos(angle2)
                fdm['atmosphere/wind-north-fps'] = 10. * math.cos(angle) * ca2
                fdm['atmosphere/wind-east-fps'] = 10. * math.sin(angle) * ca2
                fdm['atmosphere/wind-down-fps'] = 10. * math.sin(angle2)
                fdm.run()

                vg = fdm['velocities/vg-fps']
                self.assertAlmostEqual(vg, 0.0, delta=1E-7)

                vt = fdm['velocities/vt-fps']
                self.assertAlmostEqual(vt, 10., delta=1E-7)

                mach = vt / fdm['atmosphere/a-fps']
                P = fdm['atmosphere/P-psf']
                pt = P * math.pow(1+0.2*mach*mach, 3.5)
                psl = fdm['atmosphere/P-sl-psf']
                rhosl = fdm['atmosphere/rho-sl-slugs_ft3']
                A = math.pow((pt-P)/psl+1.0, 1.0/3.5)
                alpha = fdm['aero/alpha-rad']
                beta = fdm['aero/beta-rad']
                vc = math.sqrt(7.0*psl/rhosl*(A-1.0))*math.cos(alpha+pitot_angle)*math.cos(beta)

                self.assertAlmostEqual(fdm['velocities/vc-kts'],
                                       max(0.0, vc) / 1.68781, delta=1E-7)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import run [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())

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import run [as 别名]
    def testKinematicSetInitialValue(self):
        fdm = CreateFDM(self.sandbox)
        fdm.load_model('p51d')
        fdm.load_ic(self.sandbox.path_to_jsbsim_file('aircraft', 'p51d',
                                                     'reset01'), False)
        fdm.run_ic()

        fdm['gear/gear-cmd-norm'] = 0.5
        fdm['gear/gear-pos-norm'] = 0.5

        while fdm['simulation/sim-time-sec'] < 1.0:
            fdm.run()
            self.assertAlmostEqual(fdm['gear/gear-cmd-norm'], 0.5)
            self.assertAlmostEqual(fdm['gear/gear-pos-norm'], 0.5)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import run [as 别名]
 def test_steer_with_fcs(self):
     fdm = CreateFDM(self.sandbox)
     fdm.load_model('L410')
     aircraft_path = self.sandbox.path_to_jsbsim_file('aircraft')
     fdm.load_ic(os.path.join(aircraft_path, 'L410', 'reset00'), False)
     fdm.run_ic()
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 0.0)
     self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 0.0)
     fdm['fcs/steer-cmd-norm'] = 1.0
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 1.0)
     fdm.run()
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 1.0)
     self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 5.0)
     fdm['/controls/switches/full-steering-sw'] = 1.0
     fdm.run()
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 1.0)
     self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 0.0)
     fdm['/controls/switches/full-steering-sw'] = 2.0
     fdm.run()
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 1.0)
     self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 45.0)
     fdm['fcs/steer-cmd-norm'] = -0.5
     fdm.run()
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], -0.5)
     self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], -22.5)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import run [as 别名]
    def test_static_hold_down(self):
        fdm = CreateFDM(self.sandbox)
        fdm.load_model('J246')
        aircraft_path = self.sandbox.path_to_jsbsim_file('aircraft')
        fdm.load_ic(os.path.join(aircraft_path, 'J246', 'LC39'), False)
        fdm['forces/hold-down'] = 1.0
        fdm.run_ic()
        h0 = fdm['position/h-sl-ft']
        t = 0.0

        while t < 420.0:
            fdm.run()
            t = fdm['simulation/sim-time-sec']
            self.assertAlmostEqual(fdm['position/h-sl-ft'], h0, delta=1E-5)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import run [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 run [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 run [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 run [as 别名]
    def test_moments_update(self):
        script_path = self.sandbox.path_to_jsbsim_file('scripts', 'weather-balloon.xml')
        fdm = CreateFDM(self.sandbox)

        fdm.load_script(script_path)
        fdm.run_ic()

        # Moves the radio sonde to modify the CG location
        fdm.set_property_value('inertia/pointmass-location-X-inches', 5.0)

        # Check that the moment is immediately updated accordingly
        fdm.run()
        Fbz = fdm.get_property_value('forces/fbz-buoyancy-lbs')
        CGx = fdm.get_property_value('inertia/cg-x-in') / 12.0 # Converts from in to ft
        Mby = fdm.get_property_value('moments/m-buoyancy-lbsft')
        self.assertTrue(abs(Fbz * CGx + Mby) < 1E-7,
                        msg="Fbz*CGx = %f and Mby = %f do not match" % (-Fbz*CGx, Mby))

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import run [as 别名]
 def test_direct_steer(self):
     fdm = CreateFDM(self.sandbox)
     fdm.load_model('c172r')
     aircraft_path = self.sandbox.path_to_jsbsim_file('aircraft')
     fdm.load_ic(os.path.join(aircraft_path, 'c172r', 'reset00'), False)
     fdm.run_ic()
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 0.0)
     self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 0.0)
     fdm['fcs/steer-pos-deg'] = 5.0
     self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 5.0)
     fdm.run()
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 0.0)
     fdm['fcs/steer-cmd-norm'] = 1.0
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 1.0)
     fdm.run()
     self.assertAlmostEqual(fdm['fcs/steer-cmd-norm'], 1.0)
     self.assertAlmostEqual(fdm['fcs/steer-pos-deg'], 10.0)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import run [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.set_property_value('fcs/accelerometer/on', 1.0)
        # Use the standard gravity (i.e. GM/r^2)
        fdm.set_property_value('simulation/gravity-model', 0)
        # Simplifies the transformation to compare the accelerometer with the
        # gravity
        fdm.set_property_value('ic/psi-true-rad', 0.0)
        fdm.run_ic()

        while fdm.get_property_value('simulation/sim-time-sec') <= 0.5:
            fdm.run()

        fdm.set_property_value('simulation/do_simple_trim', 1)
        ax = fdm.get_property_value('accelerations/udot-ft_sec2')
        ay = fdm.get_property_value('accelerations/vdot-ft_sec2')
        az = fdm.get_property_value('accelerations/wdot-ft_sec2')
        g = fdm.get_property_value('accelerations/gravity-ft_sec2')
        theta = fdm.get_property_value('attitude/theta-rad')

        # There is a lag of one time step between the computations of the
        # accelerations and the update of the accelerometer
        fdm.run()
        fax = fdm.get_property_value('fcs/accelerometer/X')
        fay = fdm.get_property_value('fcs/accelerometer/Y')
        faz = fdm.get_property_value('fcs/accelerometer/Z')

        fax -= ax
        fay -= ay
        faz -= az

        # Deltas are relaxed because the tolerances of the trimming algorithm
        # are quite relaxed themselves.
        self.assertAlmostEqual(faz / (g * math.cos(theta)), -1.0, delta=1E-5)
        self.assertAlmostEqual(fax / (g * math.sin(theta)), 1.0, delta=1E-5)
        self.assertAlmostEqual(math.sqrt(fax*fax+fay*fay+faz*faz)/g, 1.0, delta=1E-6)

        del fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import run [as 别名]
    def testOnGround(self):
        script_name = 'c1721.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.set_property_value('fcs/accelerometer/on', 1.0)
        # Use the standard gravity (i.e. GM/r^2)
        fdm.set_property_value('simulation/gravity-model', 0)
        # Simplifies the transformation to compare the accelerometer with the
        # gravity
        fdm.set_property_value('ic/psi-true-rad', 0.0)
        fdm.run_ic()

        for i in xrange(500):
            fdm.run()

        ax = fdm.get_property_value('accelerations/udot-ft_sec2')
        ay = fdm.get_property_value('accelerations/vdot-ft_sec2')
        az = fdm.get_property_value('accelerations/wdot-ft_sec2')
        g = fdm.get_property_value('accelerations/gravity-ft_sec2')
        theta = fdm.get_property_value('attitude/theta-rad')

        # There is a lag of one time step between the computations of the
        # accelerations and the update of the accelerometer
        fdm.run()
        fax = fdm.get_property_value('fcs/accelerometer/X')
        fay = fdm.get_property_value('fcs/accelerometer/Y')
        faz = fdm.get_property_value('fcs/accelerometer/Z')

        fax -= ax
        faz -= az

        self.assertAlmostEqual(fay, 0.0, delta=1E-6)
        self.assertAlmostEqual(fax / (g * math.sin(theta)), 1.0, delta=1E-5)
        self.assertAlmostEqual(faz / (g * math.cos(theta)), -1.0, delta=1E-7)

        del fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import run [as 别名]
    def test_trim_on_ground(self):
        # Check that the trim is made with up to date initial conditions
        fdm = CreateFDM(self.sandbox)
        fdm.load_model('c172x')
        fdm['ic/theta-deg'] = 90.0
        fdm.run_ic()
        fdm['ic/theta-deg'] = 0.0
        # If the trim fails, it will raise an exception
        fdm['simulation/do_simple_trim'] = 2  # Ground trim

        # Check that the aircraft has been trimmed successfully (velocities
        # should be zero i.e. the aircraft must be motionless once trimmed).
        while fdm['simulation/sim-time-sec'] <= 1.0:
            fdm.run()
            self.assertAlmostEqual(fdm['velocities/p-rad_sec'], 0., delta=1E-4)
            self.assertAlmostEqual(fdm['velocities/q-rad_sec'], 0., delta=1E-4)
            self.assertAlmostEqual(fdm['velocities/r-rad_sec'], 0., delta=1E-4)
            self.assertAlmostEqual(fdm['velocities/u-fps'], 0.0, delta=1E-4)
            self.assertAlmostEqual(fdm['velocities/v-fps'], 0.0, delta=1E-4)
            self.assertAlmostEqual(fdm['velocities/w-fps'], 0.0, delta=1E-4)