Coverage for pySDC/projects/RDC/vanderpol_MLSDC_PFASST_test.py: 100%

1import numpy as np 

2 

3from pySDC.helpers.stats_helper import get_sorted 

4from pySDC.implementations.controller_classes.controller_nonMPI import controller_nonMPI 

5from pySDC.implementations.problem_classes.Van_der_Pol_implicit import vanderpol 

6from pySDC.implementations.sweeper_classes.generic_implicit import generic_implicit 

7from pySDC.implementations.transfer_classes.TransferMesh_NoCoarse import mesh_to_mesh 

8from pySDC.projects.RDC.equidistant_RDC import Equidistant_RDC 

9 

10 

11def run_RDC(cwd=''): 

12 """ 

13 Van der Pol's oscillator with RDC, MLRDC and PFASST 

14 

15 Args: 

16 cwd (string): current working directory 

17 

18 Returns: 

19 list: list of errors and mean number of iterations (for testing) 

20 """ 

21 

22 # set time parameters 

23 t0 = 0.0 

24 Tend = 10.0 

25 

26 # initialize level parameters 

27 level_params = dict() 

28 level_params['restol'] = 1e-10 

29 level_params['dt'] = 0.25 

30 

31 # initialize sweeper parameters 

32 sweeper_params = dict() 

33 sweeper_params['collocation_class'] = Equidistant_RDC 

34 sweeper_params['num_nodes'] = 20 

35 sweeper_params['QI'] = 'IE' 

36 

37 # initialize problem parameters 

38 problem_params = dict() 

39 problem_params['newton_tol'] = 1e-12 

40 problem_params['newton_maxiter'] = 50 

41 problem_params['mu'] = 10 

42 problem_params['u0'] = (2.0, 0) 

43 

44 # initialize step parameters 

45 step_params = dict() 

46 step_params['maxiter'] = 50 

47 

48 # initialize controller parameters 

49 controller_params = dict() 

50 controller_params['logger_level'] = 50 

51 

52 base_transfer_params = dict() 

53 # base_transfer_params['finter'] = True 

54 # base_transfer_params['coll_iorder'] = 2 

55 # base_transfer_params['coll_rorder'] = 2 

56 

57 # Fill description dictionary for easy hierarchy creation 

58 description = dict() 

59 description['problem_class'] = vanderpol 

60 description['problem_params'] = problem_params 

61 description['sweeper_class'] = generic_implicit 

62 description['sweeper_params'] = sweeper_params 

63 description['level_params'] = level_params 

64 description['step_params'] = step_params 

65 description['space_transfer_class'] = mesh_to_mesh 

66 description['base_transfer_params'] = base_transfer_params 

67 

68 results = [] 

69 ref_sol = np.load(cwd + 'data/vdp_ref.npy') 

70 

71 # instantiate the controller 

72 controller_rdc = controller_nonMPI(num_procs=1, controller_params=controller_params, description=description) 

73 

74 # get initial values on finest level 

75 P = controller_rdc.MS[0].levels[0].prob 

76 uinit = P.u_exact(t0) 

77 

78 # call main function to get things done... 

79 uend_rdc, stats_rdc = controller_rdc.run(u0=uinit, t0=t0, Tend=Tend) 

80 

81 # filter statistics by type (number of iterations) 

82 iter_counts = get_sorted(stats_rdc, type='niter', sortby='time') 

83 mean_niter = np.mean(np.array([item[1] for item in iter_counts])) 

84 

85 err = np.linalg.norm(uend_rdc - ref_sol, np.inf) / np.linalg.norm(ref_sol, np.inf) 

86 print('RDC : Mean number of iterations: %6.3f -- Error: %8.4e' % (mean_niter, err)) 

87 results.append((err, mean_niter)) 

88 

89 sweeper_params['num_nodes'] = [sweeper_params['num_nodes'], 10] 

90 controller_mlrdc = controller_nonMPI(num_procs=1, controller_params=controller_params, description=description) 

91 

92 uend_mlrdc, stats_mlrdc = controller_mlrdc.run(u0=uinit, t0=t0, Tend=Tend) 

93 

94 # filter statistics by type (number of iterations) 

95 iter_counts = get_sorted(stats_mlrdc, type='niter', sortby='time') 

96 mean_niter = np.mean(np.array([item[1] for item in iter_counts])) 

97 

98 err = np.linalg.norm(uend_mlrdc - ref_sol, np.inf) / np.linalg.norm(ref_sol, np.inf) 

99 print('MLRDC : Mean number of iterations: %6.3f -- Error: %8.4e' % (mean_niter, err)) 

100 results.append((err, mean_niter)) 

101 

102 controller_pfasst = controller_nonMPI(num_procs=10, controller_params=controller_params, description=description) 

103 

104 uend_pfasst, stats_pfasst = controller_pfasst.run(u0=uinit, t0=t0, Tend=Tend) 

105 

106 # filter statistics by type (number of iterations) 

107 iter_counts = get_sorted(stats_pfasst, type='niter', sortby='time') 

108 mean_niter = np.mean(np.array([item[1] for item in iter_counts])) 

109 

110 err = np.linalg.norm(uend_pfasst - ref_sol, np.inf) / np.linalg.norm(ref_sol, np.inf) 

111 print('PFASST(10): Mean number of iterations: %6.3f -- Error: %8.4e' % (mean_niter, err)) 

112 results.append((err, mean_niter)) 

113 

114 return results 

115 

116 

117if __name__ == "__main__": 

118 results = run_RDC()