text: import pytest
  import numpy as np
  from collections import OrderedDict
  from pypospack.potential import LennardJonesPotential
  
  testcase = OrderedDict()
  testcase['symbols'] = ['Ar']
  testcase['parameters'] = OrderedDict()
  testcase['parameters']['ArAr_sigma'] = 1.0
  testcase['parameters']['ArAr_epsilon'] = 1.0
  testcase['parameter_names'] = ['r_cut_global', 'ArAr_epsilon', 'ArAr_sigma', 'ArAr_r_cut_pair', 'ArAr_r_cut_coulomb']
  
  def test__static_variable__global_parameters():
      assert isinstance(LennardJonesPotential.global_potential_parameters,list)
      assert LennardJonesPotential.global_potential_parameters == ['r_cut_global']
  
  def test__static_variable__pair_parameters():
      assert isinstance(LennardJonesPotential.pair_potential_parameters,list)
      assert LennardJonesPotential.pair_potential_parameters == ['epsilon','sigma','r_cut_pair','r_cut_coulomb']
  
  def test____init__1sym():
      o = LennardJonesPotential(symbols=testcase['symbols'])
  
      assert isinstance(o.parameter_names,list)
      assert o.parameter_names == testcase['parameter_names']
      
      assert isinstance(o.parameters,OrderedDict)
      assert len(o.parameters) == len(o.parameter_names)
      assert all([v in o.parameters.keys() for v in testcase['parameter_names']])
  
  def test__evaluate():
      r = np.linspace(1,1000,1000)/1000*3
      o = LennardJonesPotential(symbols=testcase['symbols'])
      o.evaluate(
              r=r,
              parameters=testcase['parameters'])
      assert isinstance(o.parameters,OrderedDict)
      assert isinstance(o.potential_evaluations,OrderedDict)
      assert all([isinstance(v,np.ndarray) for k,v in o.potential_evaluations.items()])
      assert all([v.shape == r.shape for k,v in o.potential_evaluations.items()])
  
  def dev____init____1sym():
      o = LennardJonesPotential(symbols=testcase['symbols'])
      print(o.parameter_names)
      print(o.parameters.keys())
  
  def dev__evaluate():
      
      r = np.linspace(1,1000,1000)/1000*3
      o = LennardJonesPotential(symbols=testcase['symbols'])
      o.evaluate(
              r=r,
              parameters=testcase['parameters'])
      print(o.parameters)
      print(o.potential_evaluations)
  
  if __name__ == '__main__':
      dev____init____1sym()
      dev__evaluate()
  