def testSmallDistance(self):
params = r_ij, eps_ij, ro_ij = 1.6, 3.0, 2.0
self.assertAlmostEqual(energy.GetEVdwIJ(*params), 20.7675621)
def testNoEpsilon(self):
params = r_ij, eps_ij, ro_ij = 2.5, 0.0, 2.0
self.assertAlmostEqual(energy.GetEVdwIJ(*params), 0.0)
def testLargeDistance(self):
params = r_ij, eps_ij, ro_ij = 4.0, 3.0, 2.0
self.assertAlmostEqual(energy.GetEVdwIJ(*params), -0.0930176)
def testInfiniteDistance(self):
"""Asserts zero energy for infinite separation."""
params = r_ij, eps_ij, ro_ij = float('inf'), 1.0, 1.0
self.assertAlmostEqual(energy.GetEVdwIJ(*params), 0.0)
def testSmallDistance(self):
"""Asserts correct value for smaller than equilibrium separation."""
params = r_ij, eps_ij, ro_ij = 1.6, 3.0, 2.0
self.assertAlmostEqual(energy.GetEVdwIJ(*params), 20.7675621)
def testLargeDistance(self):
"""Asserts correct value for greater than equilibrium separation."""
params = r_ij, eps_ij, ro_ij = 4.0, 3.0, 2.0
self.assertAlmostEqual(energy.GetEVdwIJ(*params), -0.0930176)
def testEquilibriumDistance(self):
"""Asserts negative epsilon energy for equilibrium separation."""
params = r_ij, eps_ij, ro_ij = 2.5, 2.0, 2.5
self.assertAlmostEqual(energy.GetEVdwIJ(*params), -2.0)
def testNoEpsilon(self):
"""Asserts no vdw energy for zero epsilon."""
params = r_ij, eps_ij, ro_ij = 2.5, 0.0, 2.0
self.assertAlmostEqual(energy.GetEVdwIJ(*params), 0.0)