def testProperties(self):
lj = LennardJones()
lj.epsilon = 2.0
lj.sigma = 2.0
lj.cutoff = 4.0
lj.shift = 0.0
# here we test energy computation, as testing property access
# would always work
self.assertAlmostEqual(lj.computeEnergy(2.0), 0.0)
self.assertAlmostEqual(lj.computeEnergy(2.0 * 2.0**(1.0 / 6.0)), -2.0)
def testEnergy(self):
lj = LennardJones(epsilon=2.0, sigma=2.0)
# root
self.assertAlmostEqual(lj.computeEnergy(2.0), 0.0)
self.assertAlmostEqual(lj.computeEnergy(2.0, 0.0, 0.0), 0.0)
# minimum
self.assertAlmostEqual(lj.computeEnergy(2.0 * 2.0**(1.0 / 6.0)), -2.0)
self.assertAlmostEqual(
lj.computeEnergy(0.0, 2.0 * 2.0**(1.0 / 6.0), 0.0), -2.0)
