Ejemplo n.º 1
0
    def test_fitToData(self):
        """
        Test the Wilhoit.fitToData() method.
        """
        H298 = self.wilhoit.getEnthalpy(298)
        S298 = self.wilhoit.getEntropy(298)
        Tdata = numpy.array([300., 400., 500., 600., 800., 1000., 1500.])
        Cpdata = numpy.zeros_like(Tdata)
        for i in range(Tdata.shape[0]):
            Cpdata[i] = self.wilhoit.getHeatCapacity(Tdata[i])
        Cp0 = self.Cp0 * constants.R
        CpInf = self.CpInf * constants.R

        # Fit the Wilhoit polynomial to the data
        wilhoit = Wilhoit().fitToData(Tdata, Cpdata, Cp0, CpInf, H298, S298)

        # Check that the fit reproduces the input data
        for T in Tdata:
            Cpexp = self.wilhoit.getHeatCapacity(T)
            Cpact = wilhoit.getHeatCapacity(T)
            self.assertAlmostEqual(Cpact, Cpexp, 4)
            Hexp = self.wilhoit.getEnthalpy(T)
            Hact = wilhoit.getEnthalpy(T)
            self.assertAlmostEqual(Hact, Hexp, 3)
            Sexp = self.wilhoit.getEntropy(T)
            Sact = wilhoit.getEntropy(T)
            self.assertAlmostEqual(Sact, Sexp, 4)

        # Check that the fit reproduces the input parameters
        # Since we're fitting to data generated from a Wilhoit (and since the
        # fitting algorithm is linear least-squares), we should get the same
        # Wilhoit parameters (with a small allowance for fitting error)
        self.assertAlmostEqual(wilhoit.Cp0.value_si, self.wilhoit.Cp0.value_si,
                               6)
        self.assertAlmostEqual(wilhoit.CpInf.value_si,
                               self.wilhoit.CpInf.value_si, 6)
        self.assertAlmostEqual(wilhoit.a0, self.wilhoit.a0, 2)
        self.assertAlmostEqual(wilhoit.a1, self.wilhoit.a1, 2)
        self.assertAlmostEqual(wilhoit.a2, self.wilhoit.a2, 2)
        self.assertAlmostEqual(wilhoit.a3, self.wilhoit.a3, 2)
        self.assertAlmostEqual(wilhoit.B.value_si, self.wilhoit.B.value_si, 2)
        self.assertAlmostEqual(wilhoit.H0.value_si, self.wilhoit.H0.value_si,
                               0)
        self.assertAlmostEqual(wilhoit.S0.value_si, self.wilhoit.S0.value_si,
                               2)
 def test_fitToData(self):
     """
     Test the Wilhoit.fitToData() method.
     """
     H298 = self.wilhoit.getEnthalpy(298)
     S298 = self.wilhoit.getEntropy(298)
     Tdata = numpy.array([300.,400.,500.,600.,800.,1000.,1500.])
     Cpdata = numpy.zeros_like(Tdata)
     for i in range(Tdata.shape[0]):
         Cpdata[i] = self.wilhoit.getHeatCapacity(Tdata[i])
     Cp0 = self.Cp0 * constants.R
     CpInf = self.CpInf * constants.R
     
     # Fit the Wilhoit polynomial to the data
     wilhoit = Wilhoit().fitToData(Tdata, Cpdata, Cp0, CpInf, H298, S298)
     
     # Check that the fit reproduces the input data
     for T in Tdata:
         Cpexp = self.wilhoit.getHeatCapacity(T)
         Cpact = wilhoit.getHeatCapacity(T)
         self.assertAlmostEqual(Cpact, Cpexp, 4)
         Hexp = self.wilhoit.getEnthalpy(T)
         Hact = wilhoit.getEnthalpy(T)
         self.assertAlmostEqual(Hact, Hexp, 3)
         Sexp = self.wilhoit.getEntropy(T)
         Sact = wilhoit.getEntropy(T)
         self.assertAlmostEqual(Sact, Sexp, 4)
     
     # Check that the fit reproduces the input parameters 
     # Since we're fitting to data generated from a Wilhoit (and since the
     # fitting algorithm is linear least-squares), we should get the same
     # Wilhoit parameters (with a small allowance for fitting error)
     self.assertAlmostEqual(wilhoit.Cp0.value_si, self.wilhoit.Cp0.value_si, 6)
     self.assertAlmostEqual(wilhoit.CpInf.value_si, self.wilhoit.CpInf.value_si, 6)
     self.assertAlmostEqual(wilhoit.a0, self.wilhoit.a0, 2)
     self.assertAlmostEqual(wilhoit.a1, self.wilhoit.a1, 2)
     self.assertAlmostEqual(wilhoit.a2, self.wilhoit.a2, 2)
     self.assertAlmostEqual(wilhoit.a3, self.wilhoit.a3, 2)
     self.assertAlmostEqual(wilhoit.B.value_si, self.wilhoit.B.value_si, 2)
     self.assertAlmostEqual(wilhoit.H0.value_si, self.wilhoit.H0.value_si, 0)
     self.assertAlmostEqual(wilhoit.S0.value_si, self.wilhoit.S0.value_si, 2)
Ejemplo n.º 3
0
class TestWilhoit(unittest.TestCase):
    """
    Contains unit tests of the :class:`Wilhoit` class.
    """
    
    def setUp(self):
        """
        A function run before each unit test in this class.
        """
        self.Cp0 = 4.0
        self.CpInf = 21.5
        self.a0 = 0.0977518
        self.a1 = -16.3067
        self.a2 = 26.2524
        self.a3 = -12.6785
        self.B = 1068.68
        self.H0 = -94088. # -782.292 kJ/mol / constants.R
        self.S0 = -118.46 # -984.932 J/mol*K / constants.R
        self.Tmin = 300.
        self.Tmax = 3000.
        self.comment = 'C2H6'
        self.wilhoit = Wilhoit(
            Cp0 = (self.Cp0*constants.R,"J/(mol*K)"),
            CpInf = (self.CpInf*constants.R,"J/(mol*K)"),
            a0 = self.a0,
            a1 = self.a1,
            a2 = self.a2,
            a3 = self.a3,
            B = (self.B,"K"),
            H0 = (self.H0*0.001*constants.R,"kJ/mol"),
            S0 = (self.S0*constants.R,"J/(mol*K)"),
            Tmin = (self.Tmin,"K"),
            Tmax = (self.Tmax,"K"),
            comment = self.comment,
        )

    def tearDown(self):
        """
        Reset the database & liquid parameters for solution
        """
        import rmgpy.data.rmg
        rmgpy.data.rmg.database = None
        
        from rmgpy.rmg.model import Species as DifferentSpecies
        DifferentSpecies.solventData = None
        DifferentSpecies.solventName = None
        DifferentSpecies.solventStructure = None
        DifferentSpecies.solventViscosity = None

    def test_Cp0(self):
        """
        Test that the Wilhoit Cp0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Cp0.value_si / constants.R, self.Cp0, 6)
    
    def test_CpInf(self):
        """
        Test that the Wilhoit CpInf property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.CpInf.value_si / constants.R, self.CpInf, 6)
    
    def test_a0(self):
        """
        Test that the Wilhoit a0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a0, self.a0, 6)
    
    def test_a1(self):
        """
        Test that the Wilhoit a1 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a1, self.a1, 6)
    
    def test_a2(self):
        """
        Test that the Wilhoit a2 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a2, self.a2, 6)
    
    def test_a3(self):
        """
        Test that the Wilhoit a3 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a3, self.a3, 6)
    
    def test_B(self):
        """
        Test that the Wilhoit B property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.B.value_si, self.B, 6)
    
    def test_H0(self):
        """
        Test that the Wilhoit H0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.H0.value_si / constants.R, self.H0, 6)
    
    def test_S0(self):
        """
        Test that the Wilhoit S0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.S0.value_si / constants.R, self.S0, 6)
    
    def test_Tmin(self):
        """
        Test that the Wilhoit Tmin property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Tmin.value_si, self.Tmin, 6)
    
    def test_Tmax(self):
        """
        Test that the Wilhoit Tmax property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Tmax.value_si, self.Tmax, 6)
        
    def test_E0(self):
        """
        Test that the Wilhoit E0 property is properly calculated from Enthalpy at 0.001 K
        """
        self.assertAlmostEqual(self.wilhoit.E0.value_si, self.wilhoit.getEnthalpy(0.001), 1)
    
    def test_comment(self):
        """
        Test that the Wilhoit comment property was properly set.
        """
        self.assertEqual(self.wilhoit.comment, self.comment)
    
    def test_isTemperatureValid(self):
        """
        Test the Wilhoit.isTemperatureValid() method.
        """
        Tdata = [200,400,600,800,1000,1200,1400,1600,1800,2000]
        validdata = [False,True,True,True,True,True,True,True,True,True]
        for T, valid in zip(Tdata, validdata):
            valid0 = self.wilhoit.isTemperatureValid(T)
            self.assertEqual(valid0, valid)
        
    def test_getHeatCapacity(self):
        """
        Test the Wilhoit.getHeatCapacity() method.
        """
        Tlist = numpy.array([200,400,600,800,1000,1200,1400,1600,1800,2000])
        Cpexplist = numpy.array([5.12003, 7.80327, 10.5528, 12.8323, 14.6013, 15.9511, 16.9842, 17.7837, 18.4114, 18.9117]) * constants.R
        for T, Cpexp in zip(Tlist, Cpexplist):
            Cpact = self.wilhoit.getHeatCapacity(T)
            self.assertAlmostEqual(Cpexp / Cpact, 1.0, 3, '{0} != {1} within 3 places'.format(Cpexp, Cpact))
       
    def test_getEnthalpy(self):
        """
        Test the Wilhoit.getEnthalpy() method.
        """
        Tlist = numpy.array([200,400,600,800,1000,1200,1400,1600,1800,2000])
        Hexplist = numpy.array([-51.9303, -22.7609, -12.1050, -6.14444, -2.16433, 0.747500, 2.99646, 4.79698, 6.27618, 7.51564]) * constants.R * Tlist
        for T, Hexp in zip(Tlist, Hexplist):
            Hact = self.wilhoit.getEnthalpy(T)
            self.assertAlmostEqual(Hexp / Hact, 1.0, 3, '{0} != {1}'.format(Hexp, Hact))
                
    def test_getEntropy(self):
        """
        Test the Wilhoit.getEntropy() method.
        """
        Tlist = numpy.array([200,400,600,800,1000,1200,1400,1600,1800,2000])
        Sexplist = numpy.array([25.3095, 29.6445, 33.3398, 36.7006, 39.7629, 42.5499, 45.0898, 47.4122, 49.5445, 51.5112]) * constants.R
        for T, Sexp in zip(Tlist, Sexplist):
            Sact = self.wilhoit.getEntropy(T)
            self.assertAlmostEqual(Sexp / Sact, 1.0, 4, '{0} != {1}'.format(Sexp, Sact))

    def test_getFreeEnergy(self):
        """
        Test the Wilhoit.getFreeEnergy() method.
        """
        Tlist = numpy.array([200,400,600,800,1000,1200,1400,1600,1800,2000])
        for T in Tlist:
            Gexp = self.wilhoit.getEnthalpy(T) - T * self.wilhoit.getEntropy(T)
            Gact = self.wilhoit.getFreeEnergy(T)
            self.assertAlmostEqual(Gexp / Gact, 1.0, 4, '{0} != {1}'.format(Gexp, Gact))
    
    def test_pickle(self):
        """
        Test that a Wilhoit object can be pickled and unpickled with no loss
        of information.
        """
        import cPickle
        wilhoit = cPickle.loads(cPickle.dumps(self.wilhoit))
        self.assertAlmostEqual(self.wilhoit.Cp0.value, wilhoit.Cp0.value, 4)
        self.assertEqual(self.wilhoit.Cp0.units, wilhoit.Cp0.units)
        self.assertAlmostEqual(self.wilhoit.CpInf.value, wilhoit.CpInf.value, 3)
        self.assertEqual(self.wilhoit.CpInf.units, wilhoit.CpInf.units)
        self.assertAlmostEqual(self.wilhoit.a0, wilhoit.a0, 4)
        self.assertAlmostEqual(self.wilhoit.a1, wilhoit.a1, 4)
        self.assertAlmostEqual(self.wilhoit.a2, wilhoit.a2, 4)
        self.assertAlmostEqual(self.wilhoit.a3, wilhoit.a3, 4)
        self.assertAlmostEqual(self.wilhoit.B.value, wilhoit.B.value, 4)
        self.assertEqual(self.wilhoit.B.units, wilhoit.B.units)
        self.assertAlmostEqual(self.wilhoit.H0.value, wilhoit.H0.value, 4)
        self.assertEqual(self.wilhoit.H0.units, wilhoit.H0.units)
        self.assertAlmostEqual(self.wilhoit.S0.value, wilhoit.S0.value, 3)
        self.assertEqual(self.wilhoit.S0.units, wilhoit.S0.units)
        self.assertAlmostEqual(self.wilhoit.Tmin.value, wilhoit.Tmin.value, 4)
        self.assertEqual(self.wilhoit.Tmin.units, wilhoit.Tmin.units)
        self.assertAlmostEqual(self.wilhoit.Tmax.value, wilhoit.Tmax.value, 4)
        self.assertEqual(self.wilhoit.Tmax.units, wilhoit.Tmax.units)
        self.assertAlmostEqual(self.wilhoit.E0.value, wilhoit.E0.value, 4)
        self.assertEqual(self.wilhoit.E0.units, wilhoit.E0.units)
        self.assertEqual(self.wilhoit.comment, wilhoit.comment)
    
    def test_repr(self):
        """
        Test that a Wilhoit object can be reconstructed from its repr() output
        with no loss of information.
        """
        wilhoit = None
        exec('wilhoit = {0!r}'.format(self.wilhoit))
        self.assertAlmostEqual(self.wilhoit.Cp0.value, wilhoit.Cp0.value, 4)
        self.assertEqual(self.wilhoit.Cp0.units, wilhoit.Cp0.units)
        self.assertAlmostEqual(self.wilhoit.CpInf.value, wilhoit.CpInf.value, 3)
        self.assertEqual(self.wilhoit.CpInf.units, wilhoit.CpInf.units)
        self.assertAlmostEqual(self.wilhoit.a0, wilhoit.a0, 4)
        self.assertAlmostEqual(self.wilhoit.a1, wilhoit.a1, 4)
        self.assertAlmostEqual(self.wilhoit.a2, wilhoit.a2, 4)
        self.assertAlmostEqual(self.wilhoit.a3, wilhoit.a3, 4)
        self.assertAlmostEqual(self.wilhoit.B.value, wilhoit.B.value, 4)
        self.assertEqual(self.wilhoit.B.units, wilhoit.B.units)
        self.assertAlmostEqual(self.wilhoit.H0.value, wilhoit.H0.value, 4)
        self.assertEqual(self.wilhoit.H0.units, wilhoit.H0.units)
        self.assertAlmostEqual(self.wilhoit.S0.value, wilhoit.S0.value, 3)
        self.assertEqual(self.wilhoit.S0.units, wilhoit.S0.units)
        self.assertAlmostEqual(self.wilhoit.Tmin.value, wilhoit.Tmin.value, 4)
        self.assertEqual(self.wilhoit.Tmin.units, wilhoit.Tmin.units)
        self.assertAlmostEqual(self.wilhoit.Tmax.value, wilhoit.Tmax.value, 4)
        self.assertEqual(self.wilhoit.Tmax.units, wilhoit.Tmax.units)
        self.assertAlmostEqual(self.wilhoit.E0.value, wilhoit.E0.value, 1)
        self.assertEqual(self.wilhoit.E0.units, wilhoit.E0.units)
        self.assertEqual(self.wilhoit.comment, wilhoit.comment)

    def test_fitToData(self):
        """
        Test the Wilhoit.fitToData() method.
        """
        H298 = self.wilhoit.getEnthalpy(298)
        S298 = self.wilhoit.getEntropy(298)
        Tdata = numpy.array([300.,400.,500.,600.,800.,1000.,1500.])
        Cpdata = numpy.zeros_like(Tdata)
        for i in range(Tdata.shape[0]):
            Cpdata[i] = self.wilhoit.getHeatCapacity(Tdata[i])
        Cp0 = self.Cp0 * constants.R
        CpInf = self.CpInf * constants.R
        
        # Fit the Wilhoit polynomial to the data
        wilhoit = Wilhoit().fitToData(Tdata, Cpdata, Cp0, CpInf, H298, S298)
        
        # Check that the fit reproduces the input data
        for T in Tdata:
            Cpexp = self.wilhoit.getHeatCapacity(T)
            Cpact = wilhoit.getHeatCapacity(T)
            self.assertAlmostEqual(Cpact, Cpexp, 4)
            Hexp = self.wilhoit.getEnthalpy(T)
            Hact = wilhoit.getEnthalpy(T)
            self.assertAlmostEqual(Hact, Hexp, 3)
            Sexp = self.wilhoit.getEntropy(T)
            Sact = wilhoit.getEntropy(T)
            self.assertAlmostEqual(Sact, Sexp, 4)
        
        # Check that the fit reproduces the input parameters 
        # Since we're fitting to data generated from a Wilhoit (and since the
        # fitting algorithm is linear least-squares), we should get the same
        # Wilhoit parameters (with a small allowance for fitting error)
        self.assertAlmostEqual(wilhoit.Cp0.value_si, self.wilhoit.Cp0.value_si, 6)
        self.assertAlmostEqual(wilhoit.CpInf.value_si, self.wilhoit.CpInf.value_si, 6)
        self.assertAlmostEqual(wilhoit.a0, self.wilhoit.a0, 2)
        self.assertAlmostEqual(wilhoit.a1, self.wilhoit.a1, 2)
        self.assertAlmostEqual(wilhoit.a2, self.wilhoit.a2, 2)
        self.assertAlmostEqual(wilhoit.a3, self.wilhoit.a3, 2)
        self.assertAlmostEqual(wilhoit.B.value_si, self.wilhoit.B.value_si, 2)
        self.assertAlmostEqual(wilhoit.H0.value_si, self.wilhoit.H0.value_si, 0)
        self.assertAlmostEqual(wilhoit.S0.value_si, self.wilhoit.S0.value_si, 2)

    def testToWilhoit(self):
        """
        Test if the entropy computed from other thermo implementations is close to what Wilhoit computes.
        """

        from rmgpy import settings
        from rmgpy.data.rmg import RMGDatabase, database
        from rmgpy.species import Species

        # Load databases
        database = RMGDatabase()
        database.loadThermo(os.path.join(settings['database.directory'], 'thermo'), thermoLibraries=['Narayanaswamy'])
        database.loadSolvation(os.path.join(settings['database.directory'], 'solvation'))

        spc = Species().fromSMILES('CC')
        spc.getThermoData()

        T = 1350.# not 298K!

        # nasa to wilhoit
        nasa = spc.thermo
        Snasa = nasa.getEntropy(T)

        nasaToWh = nasa.toWilhoit()
        SnasaToWh = nasaToWh.getEntropy(T)

        self.assertAlmostEqual(Snasa, SnasaToWh, -1)
        self.assertEqual(nasa.comment,nasaToWh.comment)

        # wilhoit to nasa conversion done in nasaTest.py

        # thermo data to wilhoit:
        td = nasa.toThermoData()
        Std = td.getEntropy(T)

        wilhoit = td.toWilhoit(B=1000.)        
        Swh = wilhoit.getEntropy(T)

        self.assertAlmostEqual(Std, Swh, -1)
        self.assertEqual(td.comment,wilhoit.comment)

        # wilhoit back to thermodata
        td = wilhoit.toThermoData()
        Std = td.getEntropy(T)

        self.assertAlmostEqual(Std, Swh, -1)
        self.assertEqual(td.comment,wilhoit.comment)
Ejemplo n.º 4
0
class TestWilhoit(unittest.TestCase):
    """
    Contains unit tests of the :class:`Wilhoit` class.
    """
    def setUp(self):
        """
        A function run before each unit test in this class.
        """
        self.Cp0 = 4.0
        self.CpInf = 21.5
        self.a0 = 0.0977518
        self.a1 = -16.3067
        self.a2 = 26.2524
        self.a3 = -12.6785
        self.B = 1068.68
        self.H0 = -94088.  # -782.292 kJ/mol / constants.R
        self.S0 = -118.46  # -984.932 J/mol*K / constants.R
        self.Tmin = 300.
        self.Tmax = 3000.
        self.comment = 'C2H6'
        self.wilhoit = Wilhoit(
            Cp0=(self.Cp0 * constants.R, "J/(mol*K)"),
            CpInf=(self.CpInf * constants.R, "J/(mol*K)"),
            a0=self.a0,
            a1=self.a1,
            a2=self.a2,
            a3=self.a3,
            B=(self.B, "K"),
            H0=(self.H0 * 0.001 * constants.R, "kJ/mol"),
            S0=(self.S0 * constants.R, "J/(mol*K)"),
            Tmin=(self.Tmin, "K"),
            Tmax=(self.Tmax, "K"),
            comment=self.comment,
        )

    def test_Cp0(self):
        """
        Test that the Wilhoit Cp0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Cp0.value_si / constants.R,
                               self.Cp0, 6)

    def test_CpInf(self):
        """
        Test that the Wilhoit CpInf property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.CpInf.value_si / constants.R,
                               self.CpInf, 6)

    def test_a0(self):
        """
        Test that the Wilhoit a0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a0, self.a0, 6)

    def test_a1(self):
        """
        Test that the Wilhoit a1 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a1, self.a1, 6)

    def test_a2(self):
        """
        Test that the Wilhoit a2 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a2, self.a2, 6)

    def test_a3(self):
        """
        Test that the Wilhoit a3 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a3, self.a3, 6)

    def test_B(self):
        """
        Test that the Wilhoit B property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.B.value_si, self.B, 6)

    def test_H0(self):
        """
        Test that the Wilhoit H0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.H0.value_si / constants.R, self.H0,
                               6)

    def test_S0(self):
        """
        Test that the Wilhoit S0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.S0.value_si / constants.R, self.S0,
                               6)

    def test_Tmin(self):
        """
        Test that the Wilhoit Tmin property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Tmin.value_si, self.Tmin, 6)

    def test_Tmax(self):
        """
        Test that the Wilhoit Tmax property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Tmax.value_si, self.Tmax, 6)

    def test_E0(self):
        """
        Test that the Wilhoit E0 property is properly calculated from Enthalpy at 0.001 K
        """
        self.assertAlmostEqual(self.wilhoit.E0.value_si,
                               self.wilhoit.getEnthalpy(0.001), 1)

    def test_comment(self):
        """
        Test that the Wilhoit comment property was properly set.
        """
        self.assertEqual(self.wilhoit.comment, self.comment)

    def test_isTemperatureValid(self):
        """
        Test the Wilhoit.isTemperatureValid() method.
        """
        Tdata = [200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000]
        validdata = [
            False, True, True, True, True, True, True, True, True, True
        ]
        for T, valid in zip(Tdata, validdata):
            valid0 = self.wilhoit.isTemperatureValid(T)
            self.assertEqual(valid0, valid)

    def test_getHeatCapacity(self):
        """
        Test the Wilhoit.getHeatCapacity() method.
        """
        Tlist = numpy.array(
            [200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000])
        Cpexplist = numpy.array([
            5.12003, 7.80327, 10.5528, 12.8323, 14.6013, 15.9511, 16.9842,
            17.7837, 18.4114, 18.9117
        ]) * constants.R
        for T, Cpexp in zip(Tlist, Cpexplist):
            Cpact = self.wilhoit.getHeatCapacity(T)
            self.assertAlmostEqual(
                Cpexp / Cpact, 1.0, 3,
                '{0} != {1} within 3 places'.format(Cpexp, Cpact))

    def test_getEnthalpy(self):
        """
        Test the Wilhoit.getEnthalpy() method.
        """
        Tlist = numpy.array(
            [200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000])
        Hexplist = numpy.array([
            -51.9303, -22.7609, -12.1050, -6.14444, -2.16433, 0.747500,
            2.99646, 4.79698, 6.27618, 7.51564
        ]) * constants.R * Tlist
        for T, Hexp in zip(Tlist, Hexplist):
            Hact = self.wilhoit.getEnthalpy(T)
            self.assertAlmostEqual(Hexp / Hact, 1.0, 3,
                                   '{0} != {1}'.format(Hexp, Hact))

    def test_getEntropy(self):
        """
        Test the Wilhoit.getEntropy() method.
        """
        Tlist = numpy.array(
            [200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000])
        Sexplist = numpy.array([
            25.3095, 29.6445, 33.3398, 36.7006, 39.7629, 42.5499, 45.0898,
            47.4122, 49.5445, 51.5112
        ]) * constants.R
        for T, Sexp in zip(Tlist, Sexplist):
            Sact = self.wilhoit.getEntropy(T)
            self.assertAlmostEqual(Sexp / Sact, 1.0, 4,
                                   '{0} != {1}'.format(Sexp, Sact))

    def test_getFreeEnergy(self):
        """
        Test the Wilhoit.getFreeEnergy() method.
        """
        Tlist = numpy.array(
            [200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000])
        for T in Tlist:
            Gexp = self.wilhoit.getEnthalpy(T) - T * self.wilhoit.getEntropy(T)
            Gact = self.wilhoit.getFreeEnergy(T)
            self.assertAlmostEqual(Gexp / Gact, 1.0, 4,
                                   '{0} != {1}'.format(Gexp, Gact))

    def test_pickle(self):
        """
        Test that a Wilhoit object can be pickled and unpickled with no loss
        of information.
        """
        import cPickle
        wilhoit = cPickle.loads(cPickle.dumps(self.wilhoit))
        self.assertAlmostEqual(self.wilhoit.Cp0.value, wilhoit.Cp0.value, 4)
        self.assertEqual(self.wilhoit.Cp0.units, wilhoit.Cp0.units)
        self.assertAlmostEqual(self.wilhoit.CpInf.value, wilhoit.CpInf.value,
                               3)
        self.assertEqual(self.wilhoit.CpInf.units, wilhoit.CpInf.units)
        self.assertAlmostEqual(self.wilhoit.a0, wilhoit.a0, 4)
        self.assertAlmostEqual(self.wilhoit.a1, wilhoit.a1, 4)
        self.assertAlmostEqual(self.wilhoit.a2, wilhoit.a2, 4)
        self.assertAlmostEqual(self.wilhoit.a3, wilhoit.a3, 4)
        self.assertAlmostEqual(self.wilhoit.B.value, wilhoit.B.value, 4)
        self.assertEqual(self.wilhoit.B.units, wilhoit.B.units)
        self.assertAlmostEqual(self.wilhoit.H0.value, wilhoit.H0.value, 4)
        self.assertEqual(self.wilhoit.H0.units, wilhoit.H0.units)
        self.assertAlmostEqual(self.wilhoit.S0.value, wilhoit.S0.value, 3)
        self.assertEqual(self.wilhoit.S0.units, wilhoit.S0.units)
        self.assertAlmostEqual(self.wilhoit.Tmin.value, wilhoit.Tmin.value, 4)
        self.assertEqual(self.wilhoit.Tmin.units, wilhoit.Tmin.units)
        self.assertAlmostEqual(self.wilhoit.Tmax.value, wilhoit.Tmax.value, 4)
        self.assertEqual(self.wilhoit.Tmax.units, wilhoit.Tmax.units)
        self.assertAlmostEqual(self.wilhoit.E0.value, wilhoit.E0.value, 4)
        self.assertEqual(self.wilhoit.E0.units, wilhoit.E0.units)
        self.assertEqual(self.wilhoit.comment, wilhoit.comment)

    def test_repr(self):
        """
        Test that a Wilhoit object can be reconstructed from its repr() output
        with no loss of information.
        """
        wilhoit = None
        exec('wilhoit = {0!r}'.format(self.wilhoit))
        self.assertAlmostEqual(self.wilhoit.Cp0.value, wilhoit.Cp0.value, 4)
        self.assertEqual(self.wilhoit.Cp0.units, wilhoit.Cp0.units)
        self.assertAlmostEqual(self.wilhoit.CpInf.value, wilhoit.CpInf.value,
                               3)
        self.assertEqual(self.wilhoit.CpInf.units, wilhoit.CpInf.units)
        self.assertAlmostEqual(self.wilhoit.a0, wilhoit.a0, 4)
        self.assertAlmostEqual(self.wilhoit.a1, wilhoit.a1, 4)
        self.assertAlmostEqual(self.wilhoit.a2, wilhoit.a2, 4)
        self.assertAlmostEqual(self.wilhoit.a3, wilhoit.a3, 4)
        self.assertAlmostEqual(self.wilhoit.B.value, wilhoit.B.value, 4)
        self.assertEqual(self.wilhoit.B.units, wilhoit.B.units)
        self.assertAlmostEqual(self.wilhoit.H0.value, wilhoit.H0.value, 4)
        self.assertEqual(self.wilhoit.H0.units, wilhoit.H0.units)
        self.assertAlmostEqual(self.wilhoit.S0.value, wilhoit.S0.value, 3)
        self.assertEqual(self.wilhoit.S0.units, wilhoit.S0.units)
        self.assertAlmostEqual(self.wilhoit.Tmin.value, wilhoit.Tmin.value, 4)
        self.assertEqual(self.wilhoit.Tmin.units, wilhoit.Tmin.units)
        self.assertAlmostEqual(self.wilhoit.Tmax.value, wilhoit.Tmax.value, 4)
        self.assertEqual(self.wilhoit.Tmax.units, wilhoit.Tmax.units)
        self.assertAlmostEqual(self.wilhoit.E0.value, wilhoit.E0.value, 1)
        self.assertEqual(self.wilhoit.E0.units, wilhoit.E0.units)
        self.assertEqual(self.wilhoit.comment, wilhoit.comment)

    def test_fitToData(self):
        """
        Test the Wilhoit.fitToData() method.
        """
        H298 = self.wilhoit.getEnthalpy(298)
        S298 = self.wilhoit.getEntropy(298)
        Tdata = numpy.array([300., 400., 500., 600., 800., 1000., 1500.])
        Cpdata = numpy.zeros_like(Tdata)
        for i in range(Tdata.shape[0]):
            Cpdata[i] = self.wilhoit.getHeatCapacity(Tdata[i])
        Cp0 = self.Cp0 * constants.R
        CpInf = self.CpInf * constants.R

        # Fit the Wilhoit polynomial to the data
        wilhoit = Wilhoit().fitToData(Tdata, Cpdata, Cp0, CpInf, H298, S298)

        # Check that the fit reproduces the input data
        for T in Tdata:
            Cpexp = self.wilhoit.getHeatCapacity(T)
            Cpact = wilhoit.getHeatCapacity(T)
            self.assertAlmostEqual(Cpact, Cpexp, 4)
            Hexp = self.wilhoit.getEnthalpy(T)
            Hact = wilhoit.getEnthalpy(T)
            self.assertAlmostEqual(Hact, Hexp, 3)
            Sexp = self.wilhoit.getEntropy(T)
            Sact = wilhoit.getEntropy(T)
            self.assertAlmostEqual(Sact, Sexp, 4)

        # Check that the fit reproduces the input parameters
        # Since we're fitting to data generated from a Wilhoit (and since the
        # fitting algorithm is linear least-squares), we should get the same
        # Wilhoit parameters (with a small allowance for fitting error)
        self.assertAlmostEqual(wilhoit.Cp0.value_si, self.wilhoit.Cp0.value_si,
                               6)
        self.assertAlmostEqual(wilhoit.CpInf.value_si,
                               self.wilhoit.CpInf.value_si, 6)
        self.assertAlmostEqual(wilhoit.a0, self.wilhoit.a0, 2)
        self.assertAlmostEqual(wilhoit.a1, self.wilhoit.a1, 2)
        self.assertAlmostEqual(wilhoit.a2, self.wilhoit.a2, 2)
        self.assertAlmostEqual(wilhoit.a3, self.wilhoit.a3, 2)
        self.assertAlmostEqual(wilhoit.B.value_si, self.wilhoit.B.value_si, 2)
        self.assertAlmostEqual(wilhoit.H0.value_si, self.wilhoit.H0.value_si,
                               0)
        self.assertAlmostEqual(wilhoit.S0.value_si, self.wilhoit.S0.value_si,
                               2)
class TestWilhoit(unittest.TestCase):
    """
    Contains unit tests of the :class:`Wilhoit` class.
    """
    
    def setUp(self):
        """
        A function run before each unit test in this class.
        """
        self.Cp0 = 4.0
        self.CpInf = 21.5
        self.a0 = 0.0977518
        self.a1 = -16.3067
        self.a2 = 26.2524
        self.a3 = -12.6785
        self.B = 1068.68
        self.H0 = -94088. # -782.292 kJ/mol / constants.R
        self.S0 = -118.46 # -984.932 J/mol*K / constants.R
        self.Tmin = 300.
        self.Tmax = 3000.
        self.comment = 'C2H6'
        self.wilhoit = Wilhoit(
            Cp0 = (self.Cp0*constants.R,"J/(mol*K)"),
            CpInf = (self.CpInf*constants.R,"J/(mol*K)"),
            a0 = self.a0,
            a1 = self.a1,
            a2 = self.a2,
            a3 = self.a3,
            B = (self.B,"K"),
            H0 = (self.H0*0.001*constants.R,"kJ/mol"),
            S0 = (self.S0*constants.R,"J/(mol*K)"),
            Tmin = (self.Tmin,"K"),
            Tmax = (self.Tmax,"K"),
            comment = self.comment,
        )

    def tearDown(self):
        """
        Reset the database & liquid parameters for solution
        """
        import rmgpy.data.rmg
        rmgpy.data.rmg.database = None

    def test_Cp0(self):
        """
        Test that the Wilhoit Cp0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Cp0.value_si / constants.R, self.Cp0, 6)
    
    def test_CpInf(self):
        """
        Test that the Wilhoit CpInf property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.CpInf.value_si / constants.R, self.CpInf, 6)
    
    def test_a0(self):
        """
        Test that the Wilhoit a0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a0, self.a0, 6)
    
    def test_a1(self):
        """
        Test that the Wilhoit a1 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a1, self.a1, 6)
    
    def test_a2(self):
        """
        Test that the Wilhoit a2 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a2, self.a2, 6)
    
    def test_a3(self):
        """
        Test that the Wilhoit a3 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a3, self.a3, 6)
    
    def test_B(self):
        """
        Test that the Wilhoit B property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.B.value_si, self.B, 6)
    
    def test_H0(self):
        """
        Test that the Wilhoit H0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.H0.value_si / constants.R, self.H0, 6)
    
    def test_S0(self):
        """
        Test that the Wilhoit S0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.S0.value_si / constants.R, self.S0, 6)
    
    def test_Tmin(self):
        """
        Test that the Wilhoit Tmin property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Tmin.value_si, self.Tmin, 6)
    
    def test_Tmax(self):
        """
        Test that the Wilhoit Tmax property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Tmax.value_si, self.Tmax, 6)
        
    def test_E0(self):
        """
        Test that the Wilhoit E0 property is properly calculated from Enthalpy at 0.001 K
        """
        self.assertAlmostEqual(self.wilhoit.E0.value_si, self.wilhoit.getEnthalpy(0.001), 1)
    
    def test_comment(self):
        """
        Test that the Wilhoit comment property was properly set.
        """
        self.assertEqual(self.wilhoit.comment, self.comment)
    
    def test_isTemperatureValid(self):
        """
        Test the Wilhoit.isTemperatureValid() method.
        """
        Tdata = [200,400,600,800,1000,1200,1400,1600,1800,2000]
        validdata = [False,True,True,True,True,True,True,True,True,True]
        for T, valid in zip(Tdata, validdata):
            valid0 = self.wilhoit.isTemperatureValid(T)
            self.assertEqual(valid0, valid)
        
    def test_getHeatCapacity(self):
        """
        Test the Wilhoit.getHeatCapacity() method.
        """
        Tlist = numpy.array([200,400,600,800,1000,1200,1400,1600,1800,2000])
        Cpexplist = numpy.array([5.12003, 7.80327, 10.5528, 12.8323, 14.6013, 15.9511, 16.9842, 17.7837, 18.4114, 18.9117]) * constants.R
        for T, Cpexp in zip(Tlist, Cpexplist):
            Cpact = self.wilhoit.getHeatCapacity(T)
            self.assertAlmostEqual(Cpexp / Cpact, 1.0, 3, '{0} != {1} within 3 places'.format(Cpexp, Cpact))
       
    def test_getEnthalpy(self):
        """
        Test the Wilhoit.getEnthalpy() method.
        """
        Tlist = numpy.array([200,400,600,800,1000,1200,1400,1600,1800,2000])
        Hexplist = numpy.array([-51.9303, -22.7609, -12.1050, -6.14444, -2.16433, 0.747500, 2.99646, 4.79698, 6.27618, 7.51564]) * constants.R * Tlist
        for T, Hexp in zip(Tlist, Hexplist):
            Hact = self.wilhoit.getEnthalpy(T)
            self.assertAlmostEqual(Hexp / Hact, 1.0, 3, '{0} != {1}'.format(Hexp, Hact))
                
    def test_getEntropy(self):
        """
        Test the Wilhoit.getEntropy() method.
        """
        Tlist = numpy.array([200,400,600,800,1000,1200,1400,1600,1800,2000])
        Sexplist = numpy.array([25.3095, 29.6445, 33.3398, 36.7006, 39.7629, 42.5499, 45.0898, 47.4122, 49.5445, 51.5112]) * constants.R
        for T, Sexp in zip(Tlist, Sexplist):
            Sact = self.wilhoit.getEntropy(T)
            self.assertAlmostEqual(Sexp / Sact, 1.0, 4, '{0} != {1}'.format(Sexp, Sact))

    def test_getFreeEnergy(self):
        """
        Test the Wilhoit.getFreeEnergy() method.
        """
        Tlist = numpy.array([200,400,600,800,1000,1200,1400,1600,1800,2000])
        for T in Tlist:
            Gexp = self.wilhoit.getEnthalpy(T) - T * self.wilhoit.getEntropy(T)
            Gact = self.wilhoit.getFreeEnergy(T)
            self.assertAlmostEqual(Gexp / Gact, 1.0, 4, '{0} != {1}'.format(Gexp, Gact))
    
    def test_pickle(self):
        """
        Test that a Wilhoit object can be pickled and unpickled with no loss
        of information.
        """
        import cPickle
        wilhoit = cPickle.loads(cPickle.dumps(self.wilhoit))
        self.assertAlmostEqual(self.wilhoit.Cp0.value, wilhoit.Cp0.value, 4)
        self.assertEqual(self.wilhoit.Cp0.units, wilhoit.Cp0.units)
        self.assertAlmostEqual(self.wilhoit.CpInf.value, wilhoit.CpInf.value, 3)
        self.assertEqual(self.wilhoit.CpInf.units, wilhoit.CpInf.units)
        self.assertAlmostEqual(self.wilhoit.a0, wilhoit.a0, 4)
        self.assertAlmostEqual(self.wilhoit.a1, wilhoit.a1, 4)
        self.assertAlmostEqual(self.wilhoit.a2, wilhoit.a2, 4)
        self.assertAlmostEqual(self.wilhoit.a3, wilhoit.a3, 4)
        self.assertAlmostEqual(self.wilhoit.B.value, wilhoit.B.value, 4)
        self.assertEqual(self.wilhoit.B.units, wilhoit.B.units)
        self.assertAlmostEqual(self.wilhoit.H0.value, wilhoit.H0.value, 4)
        self.assertEqual(self.wilhoit.H0.units, wilhoit.H0.units)
        self.assertAlmostEqual(self.wilhoit.S0.value, wilhoit.S0.value, 3)
        self.assertEqual(self.wilhoit.S0.units, wilhoit.S0.units)
        self.assertAlmostEqual(self.wilhoit.Tmin.value, wilhoit.Tmin.value, 4)
        self.assertEqual(self.wilhoit.Tmin.units, wilhoit.Tmin.units)
        self.assertAlmostEqual(self.wilhoit.Tmax.value, wilhoit.Tmax.value, 4)
        self.assertEqual(self.wilhoit.Tmax.units, wilhoit.Tmax.units)
        self.assertAlmostEqual(self.wilhoit.E0.value, wilhoit.E0.value, 4)
        self.assertEqual(self.wilhoit.E0.units, wilhoit.E0.units)
        self.assertEqual(self.wilhoit.comment, wilhoit.comment)
    
    def test_repr(self):
        """
        Test that a Wilhoit object can be reconstructed from its repr() output
        with no loss of information.
        """
        wilhoit = None
        exec('wilhoit = {0!r}'.format(self.wilhoit))
        self.assertAlmostEqual(self.wilhoit.Cp0.value, wilhoit.Cp0.value, 4)
        self.assertEqual(self.wilhoit.Cp0.units, wilhoit.Cp0.units)
        self.assertAlmostEqual(self.wilhoit.CpInf.value, wilhoit.CpInf.value, 3)
        self.assertEqual(self.wilhoit.CpInf.units, wilhoit.CpInf.units)
        self.assertAlmostEqual(self.wilhoit.a0, wilhoit.a0, 4)
        self.assertAlmostEqual(self.wilhoit.a1, wilhoit.a1, 4)
        self.assertAlmostEqual(self.wilhoit.a2, wilhoit.a2, 4)
        self.assertAlmostEqual(self.wilhoit.a3, wilhoit.a3, 4)
        self.assertAlmostEqual(self.wilhoit.B.value, wilhoit.B.value, 4)
        self.assertEqual(self.wilhoit.B.units, wilhoit.B.units)
        self.assertAlmostEqual(self.wilhoit.H0.value, wilhoit.H0.value, 4)
        self.assertEqual(self.wilhoit.H0.units, wilhoit.H0.units)
        self.assertAlmostEqual(self.wilhoit.S0.value, wilhoit.S0.value, 3)
        self.assertEqual(self.wilhoit.S0.units, wilhoit.S0.units)
        self.assertAlmostEqual(self.wilhoit.Tmin.value, wilhoit.Tmin.value, 4)
        self.assertEqual(self.wilhoit.Tmin.units, wilhoit.Tmin.units)
        self.assertAlmostEqual(self.wilhoit.Tmax.value, wilhoit.Tmax.value, 4)
        self.assertEqual(self.wilhoit.Tmax.units, wilhoit.Tmax.units)
        self.assertAlmostEqual(self.wilhoit.E0.value, wilhoit.E0.value, 1)
        self.assertEqual(self.wilhoit.E0.units, wilhoit.E0.units)
        self.assertEqual(self.wilhoit.comment, wilhoit.comment)

    def test_fitToData(self):
        """
        Test the Wilhoit.fitToData() method.
        """
        H298 = self.wilhoit.getEnthalpy(298)
        S298 = self.wilhoit.getEntropy(298)
        Tdata = numpy.array([300.,400.,500.,600.,800.,1000.,1500.])
        Cpdata = numpy.zeros_like(Tdata)
        for i in range(Tdata.shape[0]):
            Cpdata[i] = self.wilhoit.getHeatCapacity(Tdata[i])
        Cp0 = self.Cp0 * constants.R
        CpInf = self.CpInf * constants.R
        
        # Fit the Wilhoit polynomial to the data
        wilhoit = Wilhoit().fitToData(Tdata, Cpdata, Cp0, CpInf, H298, S298)
        
        # Check that the fit reproduces the input data
        for T in Tdata:
            Cpexp = self.wilhoit.getHeatCapacity(T)
            Cpact = wilhoit.getHeatCapacity(T)
            self.assertAlmostEqual(Cpact, Cpexp, 4)
            Hexp = self.wilhoit.getEnthalpy(T)
            Hact = wilhoit.getEnthalpy(T)
            self.assertAlmostEqual(Hact, Hexp, 3)
            Sexp = self.wilhoit.getEntropy(T)
            Sact = wilhoit.getEntropy(T)
            self.assertAlmostEqual(Sact, Sexp, 4)
        
        # Check that the fit reproduces the input parameters 
        # Since we're fitting to data generated from a Wilhoit (and since the
        # fitting algorithm is linear least-squares), we should get the same
        # Wilhoit parameters (with a small allowance for fitting error)
        self.assertAlmostEqual(wilhoit.Cp0.value_si, self.wilhoit.Cp0.value_si, 6)
        self.assertAlmostEqual(wilhoit.CpInf.value_si, self.wilhoit.CpInf.value_si, 6)
        self.assertAlmostEqual(wilhoit.a0, self.wilhoit.a0, 2)
        self.assertAlmostEqual(wilhoit.a1, self.wilhoit.a1, 2)
        self.assertAlmostEqual(wilhoit.a2, self.wilhoit.a2, 2)
        self.assertAlmostEqual(wilhoit.a3, self.wilhoit.a3, 2)
        self.assertAlmostEqual(wilhoit.B.value_si, self.wilhoit.B.value_si, 2)
        self.assertAlmostEqual(wilhoit.H0.value_si, self.wilhoit.H0.value_si, 0)
        self.assertAlmostEqual(wilhoit.S0.value_si, self.wilhoit.S0.value_si, 2)

    def testToWilhoit(self):
        """
        Test if the entropy computed from other thermo implementations is close to what Wilhoit computes.
        """

        from rmgpy import settings
        from rmgpy.data.rmg import RMGDatabase, database
        from rmgpy.species import Species

        # Load databases
        database = RMGDatabase()
        database.loadThermo(os.path.join(settings['database.directory'], 'thermo'), thermoLibraries=['Narayanaswamy'])
        database.loadSolvation(os.path.join(settings['database.directory'], 'solvation'))

        spc = Species().fromSMILES('CC')
        spc.getThermoData()

        T = 1350.# not 298K!

        # nasa to wilhoit
        nasa = spc.thermo
        Snasa = nasa.getEntropy(T)

        nasaToWh = nasa.toWilhoit()
        SnasaToWh = nasaToWh.getEntropy(T)

        self.assertAlmostEqual(Snasa, SnasaToWh, -1)
        self.assertEqual(nasa.comment,nasaToWh.comment)

        # wilhoit to nasa conversion done in nasaTest.py

        # thermo data to wilhoit:
        td = nasa.toThermoData()
        Std = td.getEntropy(T)

        wilhoit = td.toWilhoit(B=1000.)        
        Swh = wilhoit.getEntropy(T)

        self.assertAlmostEqual(Std, Swh, -1)
        self.assertEqual(td.comment,wilhoit.comment)

        # wilhoit back to thermodata
        td = wilhoit.toThermoData()
        Std = td.getEntropy(T)

        self.assertAlmostEqual(Std, Swh, -1)
        self.assertEqual(td.comment,wilhoit.comment)
Ejemplo n.º 6
0
class TestWilhoit(unittest.TestCase):
    """
    Contains unit tests of the :class:`Wilhoit` class.
    """

    def setUp(self):
        """
        A function run before each unit test in this class.
        """
        self.Cp0 = 4.0
        self.CpInf = 21.5
        self.a0 = 0.0977518
        self.a1 = -16.3067
        self.a2 = 26.2524
        self.a3 = -12.6785
        self.B = 1068.68
        self.H0 = -94088.0  # -782.292 kJ/mol / constants.R
        self.S0 = -118.46  # -984.932 J/mol*K / constants.R
        self.Tmin = 300.0
        self.Tmax = 3000.0
        self.comment = "C2H6"
        self.wilhoit = Wilhoit(
            Cp0=(self.Cp0 * constants.R, "J/(mol*K)"),
            CpInf=(self.CpInf * constants.R, "J/(mol*K)"),
            a0=self.a0,
            a1=self.a1,
            a2=self.a2,
            a3=self.a3,
            B=(self.B, "K"),
            H0=(self.H0 * 0.001 * constants.R, "kJ/mol"),
            S0=(self.S0 * constants.R, "J/(mol*K)"),
            Tmin=(self.Tmin, "K"),
            Tmax=(self.Tmax, "K"),
            comment=self.comment,
        )

    def test_Cp0(self):
        """
        Test that the Wilhoit Cp0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Cp0.value_si / constants.R, self.Cp0, 6)

    def test_CpInf(self):
        """
        Test that the Wilhoit CpInf property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.CpInf.value_si / constants.R, self.CpInf, 6)

    def test_a0(self):
        """
        Test that the Wilhoit a0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a0, self.a0, 6)

    def test_a1(self):
        """
        Test that the Wilhoit a1 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a1, self.a1, 6)

    def test_a2(self):
        """
        Test that the Wilhoit a2 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a2, self.a2, 6)

    def test_a3(self):
        """
        Test that the Wilhoit a3 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.a3, self.a3, 6)

    def test_B(self):
        """
        Test that the Wilhoit B property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.B.value_si, self.B, 6)

    def test_H0(self):
        """
        Test that the Wilhoit H0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.H0.value_si / constants.R, self.H0, 6)

    def test_S0(self):
        """
        Test that the Wilhoit S0 property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.S0.value_si / constants.R, self.S0, 6)

    def test_Tmin(self):
        """
        Test that the Wilhoit Tmin property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Tmin.value_si, self.Tmin, 6)

    def test_Tmax(self):
        """
        Test that the Wilhoit Tmax property was properly set.
        """
        self.assertAlmostEqual(self.wilhoit.Tmax.value_si, self.Tmax, 6)

    def test_comment(self):
        """
        Test that the Wilhoit comment property was properly set.
        """
        self.assertEqual(self.wilhoit.comment, self.comment)

    def test_isTemperatureValid(self):
        """
        Test the Wilhoit.isTemperatureValid() method.
        """
        Tdata = [200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000]
        validdata = [False, True, True, True, True, True, True, True, True, True]
        for T, valid in zip(Tdata, validdata):
            valid0 = self.wilhoit.isTemperatureValid(T)
            self.assertEqual(valid0, valid)

    def test_getHeatCapacity(self):
        """
        Test the Wilhoit.getHeatCapacity() method.
        """
        Tlist = numpy.array([200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000])
        Cpexplist = (
            numpy.array([5.12003, 7.80327, 10.5528, 12.8323, 14.6013, 15.9511, 16.9842, 17.7837, 18.4114, 18.9117])
            * constants.R
        )
        for T, Cpexp in zip(Tlist, Cpexplist):
            Cpact = self.wilhoit.getHeatCapacity(T)
            self.assertAlmostEqual(Cpexp / Cpact, 1.0, 3, "{0} != {1} within 3 places".format(Cpexp, Cpact))

    def test_getEnthalpy(self):
        """
        Test the Wilhoit.getEnthalpy() method.
        """
        Tlist = numpy.array([200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000])
        Hexplist = (
            numpy.array(
                [-51.9303, -22.7609, -12.1050, -6.14444, -2.16433, 0.747500, 2.99646, 4.79698, 6.27618, 7.51564]
            )
            * constants.R
            * Tlist
        )
        for T, Hexp in zip(Tlist, Hexplist):
            Hact = self.wilhoit.getEnthalpy(T)
            self.assertAlmostEqual(Hexp / Hact, 1.0, 3, "{0} != {1}".format(Hexp, Hact))

    def test_getEntropy(self):
        """
        Test the Wilhoit.getEntropy() method.
        """
        Tlist = numpy.array([200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000])
        Sexplist = (
            numpy.array([25.3095, 29.6445, 33.3398, 36.7006, 39.7629, 42.5499, 45.0898, 47.4122, 49.5445, 51.5112])
            * constants.R
        )
        for T, Sexp in zip(Tlist, Sexplist):
            Sact = self.wilhoit.getEntropy(T)
            self.assertAlmostEqual(Sexp / Sact, 1.0, 4, "{0} != {1}".format(Sexp, Sact))

    def test_getFreeEnergy(self):
        """
        Test the Wilhoit.getFreeEnergy() method.
        """
        Tlist = numpy.array([200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000])
        for T in Tlist:
            Gexp = self.wilhoit.getEnthalpy(T) - T * self.wilhoit.getEntropy(T)
            Gact = self.wilhoit.getFreeEnergy(T)
            self.assertAlmostEqual(Gexp / Gact, 1.0, 4, "{0} != {1}".format(Gexp, Gact))

    def test_pickle(self):
        """
        Test that a Wilhoit object can be pickled and unpickled with no loss
        of information.
        """
        import cPickle

        wilhoit = cPickle.loads(cPickle.dumps(self.wilhoit))
        self.assertAlmostEqual(self.wilhoit.Cp0.value, wilhoit.Cp0.value, 4)
        self.assertEqual(self.wilhoit.Cp0.units, wilhoit.Cp0.units)
        self.assertAlmostEqual(self.wilhoit.CpInf.value, wilhoit.CpInf.value, 3)
        self.assertEqual(self.wilhoit.CpInf.units, wilhoit.CpInf.units)
        self.assertAlmostEqual(self.wilhoit.a0, wilhoit.a0, 4)
        self.assertAlmostEqual(self.wilhoit.a1, wilhoit.a1, 4)
        self.assertAlmostEqual(self.wilhoit.a2, wilhoit.a2, 4)
        self.assertAlmostEqual(self.wilhoit.a3, wilhoit.a3, 4)
        self.assertAlmostEqual(self.wilhoit.B.value, wilhoit.B.value, 4)
        self.assertEqual(self.wilhoit.B.units, wilhoit.B.units)
        self.assertAlmostEqual(self.wilhoit.H0.value, wilhoit.H0.value, 4)
        self.assertEqual(self.wilhoit.H0.units, wilhoit.H0.units)
        self.assertAlmostEqual(self.wilhoit.S0.value, wilhoit.S0.value, 3)
        self.assertEqual(self.wilhoit.S0.units, wilhoit.S0.units)
        self.assertAlmostEqual(self.wilhoit.Tmin.value, wilhoit.Tmin.value, 4)
        self.assertEqual(self.wilhoit.Tmin.units, wilhoit.Tmin.units)
        self.assertAlmostEqual(self.wilhoit.Tmax.value, wilhoit.Tmax.value, 4)
        self.assertEqual(self.wilhoit.Tmax.units, wilhoit.Tmax.units)
        self.assertEqual(self.wilhoit.comment, wilhoit.comment)

    def test_repr(self):
        """
        Test that a Wilhoit object can be reconstructed from its repr() output
        with no loss of information.
        """
        wilhoit = None
        exec("wilhoit = {0!r}".format(self.wilhoit))
        self.assertAlmostEqual(self.wilhoit.Cp0.value, wilhoit.Cp0.value, 4)
        self.assertEqual(self.wilhoit.Cp0.units, wilhoit.Cp0.units)
        self.assertAlmostEqual(self.wilhoit.CpInf.value, wilhoit.CpInf.value, 3)
        self.assertEqual(self.wilhoit.CpInf.units, wilhoit.CpInf.units)
        self.assertAlmostEqual(self.wilhoit.a0, wilhoit.a0, 4)
        self.assertAlmostEqual(self.wilhoit.a1, wilhoit.a1, 4)
        self.assertAlmostEqual(self.wilhoit.a2, wilhoit.a2, 4)
        self.assertAlmostEqual(self.wilhoit.a3, wilhoit.a3, 4)
        self.assertAlmostEqual(self.wilhoit.B.value, wilhoit.B.value, 4)
        self.assertEqual(self.wilhoit.B.units, wilhoit.B.units)
        self.assertAlmostEqual(self.wilhoit.H0.value, wilhoit.H0.value, 4)
        self.assertEqual(self.wilhoit.H0.units, wilhoit.H0.units)
        self.assertAlmostEqual(self.wilhoit.S0.value, wilhoit.S0.value, 3)
        self.assertEqual(self.wilhoit.S0.units, wilhoit.S0.units)
        self.assertAlmostEqual(self.wilhoit.Tmin.value, wilhoit.Tmin.value, 4)
        self.assertEqual(self.wilhoit.Tmin.units, wilhoit.Tmin.units)
        self.assertAlmostEqual(self.wilhoit.Tmax.value, wilhoit.Tmax.value, 4)
        self.assertEqual(self.wilhoit.Tmax.units, wilhoit.Tmax.units)
        self.assertEqual(self.wilhoit.comment, wilhoit.comment)

    def test_fitToData(self):
        """
        Test the Wilhoit.fitToData() method.
        """
        H298 = self.wilhoit.getEnthalpy(298)
        S298 = self.wilhoit.getEntropy(298)
        Tdata = numpy.array([300.0, 400.0, 500.0, 600.0, 800.0, 1000.0, 1500.0])
        Cpdata = numpy.zeros_like(Tdata)
        for i in range(Tdata.shape[0]):
            Cpdata[i] = self.wilhoit.getHeatCapacity(Tdata[i])
        Cp0 = self.Cp0 * constants.R
        CpInf = self.CpInf * constants.R

        # Fit the Wilhoit polynomial to the data
        wilhoit = Wilhoit().fitToData(Tdata, Cpdata, Cp0, CpInf, H298, S298)

        # Check that the fit reproduces the input data
        for T in Tdata:
            Cpexp = self.wilhoit.getHeatCapacity(T)
            Cpact = wilhoit.getHeatCapacity(T)
            self.assertAlmostEqual(Cpact, Cpexp, 4)
            Hexp = self.wilhoit.getEnthalpy(T)
            Hact = wilhoit.getEnthalpy(T)
            self.assertAlmostEqual(Hact, Hexp, 3)
            Sexp = self.wilhoit.getEntropy(T)
            Sact = wilhoit.getEntropy(T)
            self.assertAlmostEqual(Sact, Sexp, 4)

        # Check that the fit reproduces the input parameters
        # Since we're fitting to data generated from a Wilhoit (and since the
        # fitting algorithm is linear least-squares), we should get the same
        # Wilhoit parameters (with a small allowance for fitting error)
        self.assertAlmostEqual(wilhoit.Cp0.value_si, self.wilhoit.Cp0.value_si, 6)
        self.assertAlmostEqual(wilhoit.CpInf.value_si, self.wilhoit.CpInf.value_si, 6)
        self.assertAlmostEqual(wilhoit.a0, self.wilhoit.a0, 2)
        self.assertAlmostEqual(wilhoit.a1, self.wilhoit.a1, 2)
        self.assertAlmostEqual(wilhoit.a2, self.wilhoit.a2, 2)
        self.assertAlmostEqual(wilhoit.a3, self.wilhoit.a3, 2)
        self.assertAlmostEqual(wilhoit.B.value_si, self.wilhoit.B.value_si, 2)
        self.assertAlmostEqual(wilhoit.H0.value_si, self.wilhoit.H0.value_si, 0)
        self.assertAlmostEqual(wilhoit.S0.value_si, self.wilhoit.S0.value_si, 2)