def test_volume_error_with_self_is_zero(self):
     res = of.volume_error(self.evaluation, self.evaluation)
     self.assertAlmostEqual(res, 0, self.tolerance)
 def test_volume_error(self):
     res = of.volume_error(self.evaluation, self.simulation)
     self.assertAlmostEqual(res, -1.5666937901878677, self.tolerance)