class TestIdealGasTranslation(unittest.TestCase):
"""
Contains unit tests of the IdealGasTranslation class.
"""
def setUp(self):
"""
A function run before each unit test in this class.
"""
self.mass = 32.0
self.quantum = False
self.mode = IdealGasTranslation(
mass=(self.mass, "amu"),
quantum=self.quantum,
)
def test_get_partition_function_classical(self):
"""
Test the IdealGasTranslation.get_partition_function() method for a
classical translator.
"""
t_list = np.array([300, 500, 1000, 1500, 2000])
q_exp_list = np.array(
[7.22597e+06, 2.59130e+07, 1.46586e+08, 4.03944e+08, 8.29217e+08])
for temperature, q_exp in zip(t_list, q_exp_list):
q_act = self.mode.get_partition_function(temperature)
self.assertAlmostEqual(q_exp, q_act, delta=1e-4 * q_exp)
def test_get_heat_capacity_classical(self):
"""
Test the IdealGasTranslation.get_heat_capacity() method using a classical
translator.
"""
t_list = np.array([300, 500, 1000, 1500, 2000])
cv_exp_list = np.array([2.5, 2.5, 2.5, 2.5, 2.5]) * constants.R
for temperature, cv_exp in zip(t_list, cv_exp_list):
cv_act = self.mode.get_heat_capacity(temperature)
self.assertAlmostEqual(cv_exp, cv_act, delta=1e-4 * cv_exp)
def test_get_enthalpy_classical(self):
"""
Test the IdealGasTranslation.get_enthalpy() method using a classical
translator.
"""
t_list = np.array([300, 500, 1000, 1500, 2000])
h_exp_list = np.array([2.5, 2.5, 2.5, 2.5, 2.5]) * constants.R * t_list
for temperature, h_exp in zip(t_list, h_exp_list):
h_act = self.mode.get_enthalpy(temperature)
self.assertAlmostEqual(h_exp, h_act, delta=1e-4 * h_exp)
def test_get_entropy_classical(self):
"""
Test the IdealGasTranslation.get_entropy() method using a classical
translator.
"""
t_list = np.array([300, 500, 1000, 1500, 2000])
s_exp_list = np.array([18.2932, 19.5703, 21.3031, 22.3168, 23.0360
]) * constants.R
for temperature, s_exp in zip(t_list, s_exp_list):
s_act = self.mode.get_entropy(temperature)
self.assertAlmostEqual(s_exp, s_act, delta=1e-4 * s_exp)
def test_get_sum_of_states_classical(self):
"""
Test the IdealGasTranslation.get_sum_of_states() method using a classical
translator.
"""
e_list = np.arange(0, 10000 * 11.96, 1 * 11.96)
sum_states = self.mode.get_sum_of_states(e_list)
dens_states = self.mode.get_density_of_states(e_list)
for n in range(10, len(e_list)):
self.assertTrue(
0.8 < np.sum(dens_states[0:n]) / sum_states[n - 1] < 1.25,
'{0} != {1}'.format(np.sum(dens_states[0:n]), sum_states[n]))
def test_get_density_of_states_classical(self):
"""
Test the IdealGasTranslation.get_density_of_states() method using a
classical translator.
"""
e_list = np.arange(0, 10000 * 11.96, 1 * 11.96)
dens_states = self.mode.get_density_of_states(e_list)
temperature = 100
q_act = np.sum(dens_states *
np.exp(-e_list / constants.R / temperature))
q_exp = self.mode.get_partition_function(temperature)
self.assertAlmostEqual(q_exp, q_act, delta=1e-6 * q_exp)
def test_repr(self):
"""
Test that an IdealGasTranslation object can be reconstructed from its
repr() output with no loss of information.
"""
namespace = {}
exec('mode = {0!r}'.format(self.mode), globals(), namespace)
self.assertIn('mode', namespace)
mode = namespace['mode']
self.assertAlmostEqual(self.mode.mass.value, mode.mass.value, 6)
self.assertEqual(self.mode.mass.units, mode.mass.units)
self.assertEqual(self.mode.quantum, mode.quantum)
def test_pickle(self):
"""
Test that a IdealGasTranslation object can be pickled and unpickled
with no loss of information.
"""
import pickle
mode = pickle.loads(pickle.dumps(self.mode, -1))
self.assertAlmostEqual(self.mode.mass.value, mode.mass.value, 6)
self.assertEqual(self.mode.mass.units, mode.mass.units)
self.assertEqual(self.mode.quantum, mode.quantum)
